This study investigated whether selective irradiation of vascular endothelial cells contributes to the loss of intestinal crypt stem cells and development of gastrointestinal syndrome. Mice received whole-body neutron irradiation, with or without boron-containing liposomes in the blood to selectively increase radiation dose to endothelial cells. Intestinal crypt regeneration was then assessed. The results showed that increasing the endothelial cell dose up to 3-fold did not further reduce crypt stem cell survival beyond the effects of whole-body irradiation alone. This indicates that endothelial cell damage is not causative for loss of intestinal crypt stem cells or development of gastrointestinal syndrome.
This study used proteomic techniques like 2D-DIGE and mass spectrometry to analyze changes in the sickle red blood cell membrane proteome due to treatment with hydroxyurea (HU). The study identified several proteins whose levels significantly increased or decreased with HU treatment. Notably, the antioxidant enzyme catalase showed increased tyrosine phosphorylation when treated with HU, suggesting HU may stimulate catalase activity in sickle cells through post-translational modifications rather than new protein synthesis. This study provides insights into additional cellular mechanisms through which HU may improve sickle cell pathology beyond increasing fetal hemoglobin levels.
Adipose derived osteoblasts cells from fat tissuesvijisenbiotech
This study characterized and compared surface proteins of primary osteoblasts isolated from iliac crest bone and osteoblast-like cells differentiated from adipose-derived mesenchymal stem cells. Gene and protein expression analysis using RT-PCR and western blotting showed that both cell types expressed osteoblast markers like osteocalcin, alkaline phosphatase, and collagen type 1, though osteocalcin expression was lower in adipose-derived cells. The study also found expression of stem cell markers and nucleostemin in both osteoblasts and adipose-derived osteoblast-like cells.
This document describes a study on expressing recombinant nanobodies in E. coli cells, extracting the proteins, and purifying them. E. coli WK6 cells were transformed with a plasmid containing the nanobody gene and expression was induced with IPTG. The cells were lysed and the proteins in the periplasmic space were extracted. Purification was done using immobilized metal affinity chromatography to bind the histidine-tagged nanobody, which was then eluted with imidazole buffer. SDS-PAGE and Western blot were used to analyze the expression and purity of the nanobody.
The document summarizes a study on the role of selenium and zinc in regeneration of the germinal epithelium following lead toxicity in Wistar rats. The study found that lead toxicity causes testicular damage and suppresses cell proliferation. It was shown that supplementation with selenium and zinc reduced lead-induced toxicity by promoting cell proliferation and regeneration as seen by Ki67 immunohistochemistry. The study demonstrates that selenium and zinc can help reduce the damaging effects of lead on the testes through their antioxidant properties and roles in cell growth.
Hepatotoxic effects of potassium bromate on adult wistar ratsAlexander Decker
This study examined the histopathological effects of orally administered potassium bromate (KBrO3) on the liver tissues of rats. Rats were divided into groups that received daily doses of 0 mg/kg BW (control), 50 mg/kg BW, 100 mg/kg BW, or 200 mg/kg BW of KBrO3 for 35 days. Rats that received 200 mg/kg BW died within 20 days. Liver tissues were examined after sacrifice; the control group showed normal histology while experimental groups showed sinusoidal dilation and degenerative changes, with effects increasing in severity with higher doses. The study demonstrated dose-dependent histopathological changes in rat liver tissues exposed to KBr
This study aimed to optimize the fabrication of fiber templated hydrogels containing conduits, improve seeding of human mesenchymal stem cells (hMSCs) onto the hydrogels, and differentiate the hMSCs into cardiomyocytes inside the hydrogels. Researchers fabricated poly(ethylene glycol) diacrylate hydrogels containing zein fiber conduits, seeded hMSCs at different densities, and attempted to induce cardiomyocyte differentiation over 16 days. Immunostaining showed some actin formation but no evidence of successful cardiomyocyte differentiation within the hydrogels or 2D controls. Further work is needed to optimize differentiation.
This document discusses superoxide dismutases (SODs) in the bacteria Azotobacter chroococcum and Azotobacter vinelandii. It finds that:
1) A. chroococcum and A. vinelandii only contain iron-containing SOD and copper-zinc SOD, and do not contain manganese SOD.
2) Genomic DNA analysis using sodA- and sodB-specific primers only produced a product for sodB, and not sodA, disputing a previous report that A. chroococcum contains manganese SOD.
3) The results confirm previous findings of iron SOD and copper-z
Take part in research to combat atherosclerosisXplore Health
Protocol for youngsters to carry out a bacterial transformation in a lab. The protocol follows a line of biomedical research which focuses on the study of a potential therapeutic target that could be recognised by a drug against atherosclerosis. The experiment protocol is an opportunity for science centres, museums and schools to replicate a real experiment done in a real lab doing research on drug discovery.
This study used proteomic techniques like 2D-DIGE and mass spectrometry to analyze changes in the sickle red blood cell membrane proteome due to treatment with hydroxyurea (HU). The study identified several proteins whose levels significantly increased or decreased with HU treatment. Notably, the antioxidant enzyme catalase showed increased tyrosine phosphorylation when treated with HU, suggesting HU may stimulate catalase activity in sickle cells through post-translational modifications rather than new protein synthesis. This study provides insights into additional cellular mechanisms through which HU may improve sickle cell pathology beyond increasing fetal hemoglobin levels.
Adipose derived osteoblasts cells from fat tissuesvijisenbiotech
This study characterized and compared surface proteins of primary osteoblasts isolated from iliac crest bone and osteoblast-like cells differentiated from adipose-derived mesenchymal stem cells. Gene and protein expression analysis using RT-PCR and western blotting showed that both cell types expressed osteoblast markers like osteocalcin, alkaline phosphatase, and collagen type 1, though osteocalcin expression was lower in adipose-derived cells. The study also found expression of stem cell markers and nucleostemin in both osteoblasts and adipose-derived osteoblast-like cells.
This document describes a study on expressing recombinant nanobodies in E. coli cells, extracting the proteins, and purifying them. E. coli WK6 cells were transformed with a plasmid containing the nanobody gene and expression was induced with IPTG. The cells were lysed and the proteins in the periplasmic space were extracted. Purification was done using immobilized metal affinity chromatography to bind the histidine-tagged nanobody, which was then eluted with imidazole buffer. SDS-PAGE and Western blot were used to analyze the expression and purity of the nanobody.
The document summarizes a study on the role of selenium and zinc in regeneration of the germinal epithelium following lead toxicity in Wistar rats. The study found that lead toxicity causes testicular damage and suppresses cell proliferation. It was shown that supplementation with selenium and zinc reduced lead-induced toxicity by promoting cell proliferation and regeneration as seen by Ki67 immunohistochemistry. The study demonstrates that selenium and zinc can help reduce the damaging effects of lead on the testes through their antioxidant properties and roles in cell growth.
Hepatotoxic effects of potassium bromate on adult wistar ratsAlexander Decker
This study examined the histopathological effects of orally administered potassium bromate (KBrO3) on the liver tissues of rats. Rats were divided into groups that received daily doses of 0 mg/kg BW (control), 50 mg/kg BW, 100 mg/kg BW, or 200 mg/kg BW of KBrO3 for 35 days. Rats that received 200 mg/kg BW died within 20 days. Liver tissues were examined after sacrifice; the control group showed normal histology while experimental groups showed sinusoidal dilation and degenerative changes, with effects increasing in severity with higher doses. The study demonstrated dose-dependent histopathological changes in rat liver tissues exposed to KBr
This study aimed to optimize the fabrication of fiber templated hydrogels containing conduits, improve seeding of human mesenchymal stem cells (hMSCs) onto the hydrogels, and differentiate the hMSCs into cardiomyocytes inside the hydrogels. Researchers fabricated poly(ethylene glycol) diacrylate hydrogels containing zein fiber conduits, seeded hMSCs at different densities, and attempted to induce cardiomyocyte differentiation over 16 days. Immunostaining showed some actin formation but no evidence of successful cardiomyocyte differentiation within the hydrogels or 2D controls. Further work is needed to optimize differentiation.
This document discusses superoxide dismutases (SODs) in the bacteria Azotobacter chroococcum and Azotobacter vinelandii. It finds that:
1) A. chroococcum and A. vinelandii only contain iron-containing SOD and copper-zinc SOD, and do not contain manganese SOD.
2) Genomic DNA analysis using sodA- and sodB-specific primers only produced a product for sodB, and not sodA, disputing a previous report that A. chroococcum contains manganese SOD.
3) The results confirm previous findings of iron SOD and copper-z
Take part in research to combat atherosclerosisXplore Health
Protocol for youngsters to carry out a bacterial transformation in a lab. The protocol follows a line of biomedical research which focuses on the study of a potential therapeutic target that could be recognised by a drug against atherosclerosis. The experiment protocol is an opportunity for science centres, museums and schools to replicate a real experiment done in a real lab doing research on drug discovery.
Dna hydrogel microspheres and their potential applications for protein delive...Giovanne Delechiave
This document discusses DNA hydrogel microspheres formed using microfluidic channels and their potential applications for protein delivery and live cell monitoring. Microfluidic channels were used to generate uniform DNA hydrogel microspheres in the size range of 20-90 μm. The microspheres showed controlled release of encapsulated proteins over time, with larger microspheres releasing proteins more slowly. Live cells were also successfully encapsulated in the microspheres and remained viable for several days, demonstrating potential for single cell monitoring applications. The microsphere format addresses limitations of bulk gels and provides opportunities for protein delivery and cell-based studies.
Gossypol is a polyphenolic aldehyde that is produced in the cotton plant. Since long it has been reported
to possess antiproliferative activity against a variety of cancer cell lines as well as tumor regression in
animal models. However, the toxicity of gossypol does not permit it to be an effective antitumor agent.
One of the derivatives of gossypol to show promising results is apogossypolone. For example, it has been
shown to specifically target tumor growth in hepatocellular carcinoma xenograft in nude mice without
causing any damage to normal tissue.
BLIRT is a biotechnology company in Gdansk, Poland that offers outsourced R&D services including biology and chemistry services. It has modern laboratories and a team of over 30 employees, including 22 researchers of which 9 have PhDs. BLIRT has the equipment and expertise to handle projects of all sizes, from gene synthesis to protein production and purification to analytical testing. It works with clients through different collaboration models including fee-for-service, co-development, FTE, and consulting. Key benefits include competitive pricing, short deadlines, scientific expertise, and state-of-the-art facilities.
The document discusses animal cloning techniques and applications. It describes the process of producing cloned livestock which includes preparing donor nuclei cells, removing the nucleus from recipient oocytes, cell fusion via electrofusion, and activating the cloned embryos. Factors that influence the efficiency of cloning are discussed such as the cell cycle stage of the donor cell and age of the recipient oocyte. Methods of activating the cloned embryos are also presented.
ABSTRACT- The present study was conducted to investigate the effect of cadmium chloride on Histoarchiteceture of head kidney of fresh water fish Heteropneustes fossilis. The fishes were exposed to 0.5 ppm of cadmium chloride for 21 days. The most remarkable changes in head kidney, due to cadmium chloride were lysed condition of interrenal and chromaffin cells. The traces of cytoplasm had dark brown to black coloured cytoplasm. Most of cells are deformed and necrotic condition. Their size was significant at (P< 0.01 and 0.001) increased after cadmium chloride. All these changes will be recovered by herbal compound i.e. Ashwagandha. The damaged tissues were recovered in already treated group.
Key-words- Ashwagandha, Cadmium chloride, Chromaffin cells, Heteropneustes fossilis, Histopathology, Interrenal cells
- The study investigated the effect of calcium chloride concentration on the transformation efficiency of E. coli with plasmids pUC19 and pBR322, which differ in size.
- Maximum transformation efficiency was observed at 0.15M CaCl2 for pUC19 and 0.1M CaCl2 for the larger pBR322 plasmid.
- Increasing calcium chloride concentration above these levels decreased transformation efficiency for both plasmids, with no transformants observed above 0.2M, possibly due to decreased cell viability in hypertonic conditions.
1) Mice were orally administered gold-core/silver-shell nanoparticles (Au/AgNPs) or a control over 7 days to examine genotoxicity.
2) Peripheral blood was collected at 7 days, 14 days, and 21 days and analyzed using biomarkers for DNA damage (γ-H2AX foci and 8-oxoG) and chromosomal damage (micronuclei).
3) Results showed an increase in γ-H2AX foci, a marker for double-strand DNA breaks, in treated mice at 14 days, but no differences in the other biomarkers between treated and control mice.
This document summarizes an investigation into how gut microflora affects endogenous metabolic pathways using mass spectrometry-based metabolomics. Pseudo germ-free rats were used as a model by administering antibiotics to suppress gut microflora. Urine metabolites were then analyzed and compared between control and pseudo germ-free rats using UPLC-QTOF-MS. Validation steps included repeatability testing of QC samples and a test mixture to ensure method reliability. Multivariate analysis of metabolic profiles identified differences between control and pseudo germ-free groups, suggesting gut microflora influences certain metabolic pathways.
High efficiency 5 min transformation of escherichia coliCAS0609
This document describes a new method for transforming E. coli cells that takes only 5 minutes, compared to the standard 1.5 hour protocol. Key findings include:
1) Incubating cells with DNA on ice for 1-180 minutes before spreading directly onto pre-warmed plates at 37°C resulted in up to double the transformation efficiency compared to the standard heat shock method.
2) For most antibiotic resistance markers, there was no advantage to the standard 30-60 minute recovery period at 37°C after heat shock - the direct spreading method worked as well.
3) The new 5 minute method produced similar high transformation rates for a variety of plasmid and cell line combinations tested.
Gene therapy aims to cure β-thalassemias by using lentiviral vectors to insert functional β-globin genes into hematopoietic stem cells. The first patient treated achieved long-term transfusion independence with stable multi-year expression of the corrected globin. Analysis found most genetically modified cells contained the vector integrated near the HMGA2 gene, though the majority of cells remained unmodified. Ongoing work continues to optimize the therapy.
Non invasive high resolution in vivo imaging of alpha-naphthylisothiocyanate
(ANIT) induced hepatobiliary toxicity in STII medaka
Ron Hardman∗, Seth Kullman, Bonny Yuen, David E. Hinton
Duke University, Nicholas School of the Environment and Earth Sciences, Durham, NC 27708, United States
1. ATIT is an institute in Taiwan that studies animal technology and iPSCs. JB Gurdon's 1962 nuclear transfer experiments in Xenopus laid the foundation for iPSC research. In 2006, Shinya Yamanaka generated iPSCs from mouse fibroblasts using four factors. In 2009, Hongyan Zhou generated piPSCs from human fibroblasts using recombinant proteins instead of genes.
2. Reprogramming efficiency for iPSCs is low (0.01-0.5%) due to viral integration and oncogene expression from reprogramming factors. Telomeres in iPSCs are shorter than ESCs initially but can acquire length similar to ESCs with more cell divisions. Cancerous iPS
Radiation Response of Bacteria Associated with Human Cancellous BoneIOSR Journals
Cancellous bones from twenty five live tissue donors were tested for bacterial contamination and initial bioburden ranged from 4.1×101 to 3.1×103 cfu/g (average 9.0×102 cfu/g). Forty six representative bacterial isolates were characterized on the basis of morphological, cultural and biochemical characteristics. Staphylococcus spp. was found to be predominant contaminant in tissue samples (41.30%). To assess the radiation resistance all the bacterial isolates were exposed to 1 to 10 kGy gamma radiation from 60Co gamma source. The radiation decimal reduction dose values (D10) and twelve log reduction values (12 D value) of the isolates were calculated. D10 values of the isolates were ranged from 0.59 to 1.20 kGy. Among the studied bacterial isolates, Streptococcus spp. was the most radioresistant isolates (D10 value 0.93-1.20 kGy) and three of the Streptococcus spp. survived up to 8 kGy. All the bacterial isolates were killed at 9 kGy. Twelve log reduction value (12D value) of the most resistant isolate was 14.4 kGy. These results indicate that standard radiation sterilization dose (25 kGy) is satisfactory for the sterilization of the cancellous bone allografts
This document reports on the first evidence that Correia Repeat Enclosed Elements (CREE), which resemble insertion sequence elements in Neisseria gonorrhoeae, can move via inversion within the bacterial genome. Analysis of whole genome sequencing data from N. gonorrhoeae cultured under normal and stress conditions for 8 weeks found 38 CREE that had inverted orientation compared to the reference genome. Inversions occurred more frequently under stress. The inversions provide evidence that CREE can mobilize within the chromosome via inversion rather than translocation. Some inverted CREE were found to contain promoters, suggesting inversion may regulate gene expression.
1) Xenopus laevis oocytes exposed to amyloid-β aggregate developed oscillatory electric activity (blips) recorded via two-microelectrode voltage clamp.
2) The blips increased in amplitude over time from 3.8 nA initially to 6.8 nA after 15 minutes of amyloid-β aggregate exposure, similar to the effects of channel-forming agents amphotericin B and gramicidin.
3) The amyloid-β aggregate-induced currents were dependent on extracellular calcium and disrupted calcium-dependent currents between oocytes and surrounding follicular cells. Electron microscopy also revealed dissociation of follicular cells from the oocytes.
This document summarizes the expression of recombinant β-lactoglobulin (rBLG) in prokaryotic and eukaryotic cells. In Escherichia coli, rBLG was expressed with a pET26 vector and was found predominantly in a denatured form, even when expressed in the periplasm. In eukaryotic cells like COS-7 and mouse tibialis muscle, rBLG was expressed in its native conformation. The authors quantified rBLG expression using immunoassays that distinguish between native and denatured rBLG. They found higher expression levels and native folding of rBLG in eukaryotic systems compared to prokaryotic expression
This document discusses the multifunctional roles of antimicrobial polypeptides in innate immunity. While initially studied for their antibacterial properties, these polypeptides are now recognized to have diverse inflammatory and immunomodulatory functions. For example, the cathelicidin LL-37/hCAP-18 induces angiogenesis in addition to its antimicrobial activity. The discovery of additional functions raises new questions about using these polypeptides therapeutically given their potential effects on multiple biological pathways. Defining their precise roles in vivo remains an ongoing challenge due to the complex interplay of factors in natural infections.
This document summarizes a study that investigated how mechanical forces applied to integrin receptors control intracellular signaling in osteoblasts. The researchers found that cyclic forces applied to the beta-1 integrin subunit at 1 Hz were more effective at stimulating calcium responses in osteoblasts than continuous forces. Cyclic forces also induced increased tyrosine phosphorylation of cytoskeleton-anchored proteins and greater activation of focal adhesion kinase and mitogen-activated protein kinase compared to continuous forces. These responses depended on an intact cytoskeleton and the presence of intracellular calcium. Analysis of spatial calcium signals revealed they originated near the stressed receptors, indicating cells can sense local stress via integrins.
Comparison of 7 Epithermal Neutron Beamskent.riley
This document compares the dosimetric characteristics of seven epithermal neutron beams used for boron neutron capture therapy (BNCT) clinical trials in Sweden, Finland, Czech Republic, Netherlands, and United States. Measurements were taken of neutron fluence and absorbed dose in air and in a water phantom using standardized methods. Results showed the fast neutron and photon contamination levels varied between facilities, as did the epithermal neutron flux intensities available. However, penetration depth was sufficient (>8 cm) for treating brain lesions at the midline for all beams. The data provide the first consistent measurement of beam performance across centers and will help normalize calculated patient dosimetry between facilities.
Boronated Monoclonal Antibody LA84 for BNCTkent.riley
1) The study evaluated a boronated monoclonal antibody (BD-L8A4) that targets the EGFRvIII receptor for the treatment of EGFRvIII-positive rat glioma (F98npEGFRvIII) using boron neutron capture therapy (BNCT).
2) Biodistribution studies found higher retention of BD-L8A4 in EGFRvIII-positive tumors compared to negative tumors after 24 hours.
3) BNCT studies then showed that F98npEGFRvIII-bearing rats treated with BD-L8A4 alone or with boronophenylalanine (BPA) had significantly prolonged survival compared to controls, with some rats
Dna hydrogel microspheres and their potential applications for protein delive...Giovanne Delechiave
This document discusses DNA hydrogel microspheres formed using microfluidic channels and their potential applications for protein delivery and live cell monitoring. Microfluidic channels were used to generate uniform DNA hydrogel microspheres in the size range of 20-90 μm. The microspheres showed controlled release of encapsulated proteins over time, with larger microspheres releasing proteins more slowly. Live cells were also successfully encapsulated in the microspheres and remained viable for several days, demonstrating potential for single cell monitoring applications. The microsphere format addresses limitations of bulk gels and provides opportunities for protein delivery and cell-based studies.
Gossypol is a polyphenolic aldehyde that is produced in the cotton plant. Since long it has been reported
to possess antiproliferative activity against a variety of cancer cell lines as well as tumor regression in
animal models. However, the toxicity of gossypol does not permit it to be an effective antitumor agent.
One of the derivatives of gossypol to show promising results is apogossypolone. For example, it has been
shown to specifically target tumor growth in hepatocellular carcinoma xenograft in nude mice without
causing any damage to normal tissue.
BLIRT is a biotechnology company in Gdansk, Poland that offers outsourced R&D services including biology and chemistry services. It has modern laboratories and a team of over 30 employees, including 22 researchers of which 9 have PhDs. BLIRT has the equipment and expertise to handle projects of all sizes, from gene synthesis to protein production and purification to analytical testing. It works with clients through different collaboration models including fee-for-service, co-development, FTE, and consulting. Key benefits include competitive pricing, short deadlines, scientific expertise, and state-of-the-art facilities.
The document discusses animal cloning techniques and applications. It describes the process of producing cloned livestock which includes preparing donor nuclei cells, removing the nucleus from recipient oocytes, cell fusion via electrofusion, and activating the cloned embryos. Factors that influence the efficiency of cloning are discussed such as the cell cycle stage of the donor cell and age of the recipient oocyte. Methods of activating the cloned embryos are also presented.
ABSTRACT- The present study was conducted to investigate the effect of cadmium chloride on Histoarchiteceture of head kidney of fresh water fish Heteropneustes fossilis. The fishes were exposed to 0.5 ppm of cadmium chloride for 21 days. The most remarkable changes in head kidney, due to cadmium chloride were lysed condition of interrenal and chromaffin cells. The traces of cytoplasm had dark brown to black coloured cytoplasm. Most of cells are deformed and necrotic condition. Their size was significant at (P< 0.01 and 0.001) increased after cadmium chloride. All these changes will be recovered by herbal compound i.e. Ashwagandha. The damaged tissues were recovered in already treated group.
Key-words- Ashwagandha, Cadmium chloride, Chromaffin cells, Heteropneustes fossilis, Histopathology, Interrenal cells
- The study investigated the effect of calcium chloride concentration on the transformation efficiency of E. coli with plasmids pUC19 and pBR322, which differ in size.
- Maximum transformation efficiency was observed at 0.15M CaCl2 for pUC19 and 0.1M CaCl2 for the larger pBR322 plasmid.
- Increasing calcium chloride concentration above these levels decreased transformation efficiency for both plasmids, with no transformants observed above 0.2M, possibly due to decreased cell viability in hypertonic conditions.
1) Mice were orally administered gold-core/silver-shell nanoparticles (Au/AgNPs) or a control over 7 days to examine genotoxicity.
2) Peripheral blood was collected at 7 days, 14 days, and 21 days and analyzed using biomarkers for DNA damage (γ-H2AX foci and 8-oxoG) and chromosomal damage (micronuclei).
3) Results showed an increase in γ-H2AX foci, a marker for double-strand DNA breaks, in treated mice at 14 days, but no differences in the other biomarkers between treated and control mice.
This document summarizes an investigation into how gut microflora affects endogenous metabolic pathways using mass spectrometry-based metabolomics. Pseudo germ-free rats were used as a model by administering antibiotics to suppress gut microflora. Urine metabolites were then analyzed and compared between control and pseudo germ-free rats using UPLC-QTOF-MS. Validation steps included repeatability testing of QC samples and a test mixture to ensure method reliability. Multivariate analysis of metabolic profiles identified differences between control and pseudo germ-free groups, suggesting gut microflora influences certain metabolic pathways.
High efficiency 5 min transformation of escherichia coliCAS0609
This document describes a new method for transforming E. coli cells that takes only 5 minutes, compared to the standard 1.5 hour protocol. Key findings include:
1) Incubating cells with DNA on ice for 1-180 minutes before spreading directly onto pre-warmed plates at 37°C resulted in up to double the transformation efficiency compared to the standard heat shock method.
2) For most antibiotic resistance markers, there was no advantage to the standard 30-60 minute recovery period at 37°C after heat shock - the direct spreading method worked as well.
3) The new 5 minute method produced similar high transformation rates for a variety of plasmid and cell line combinations tested.
Gene therapy aims to cure β-thalassemias by using lentiviral vectors to insert functional β-globin genes into hematopoietic stem cells. The first patient treated achieved long-term transfusion independence with stable multi-year expression of the corrected globin. Analysis found most genetically modified cells contained the vector integrated near the HMGA2 gene, though the majority of cells remained unmodified. Ongoing work continues to optimize the therapy.
Non invasive high resolution in vivo imaging of alpha-naphthylisothiocyanate
(ANIT) induced hepatobiliary toxicity in STII medaka
Ron Hardman∗, Seth Kullman, Bonny Yuen, David E. Hinton
Duke University, Nicholas School of the Environment and Earth Sciences, Durham, NC 27708, United States
1. ATIT is an institute in Taiwan that studies animal technology and iPSCs. JB Gurdon's 1962 nuclear transfer experiments in Xenopus laid the foundation for iPSC research. In 2006, Shinya Yamanaka generated iPSCs from mouse fibroblasts using four factors. In 2009, Hongyan Zhou generated piPSCs from human fibroblasts using recombinant proteins instead of genes.
2. Reprogramming efficiency for iPSCs is low (0.01-0.5%) due to viral integration and oncogene expression from reprogramming factors. Telomeres in iPSCs are shorter than ESCs initially but can acquire length similar to ESCs with more cell divisions. Cancerous iPS
Radiation Response of Bacteria Associated with Human Cancellous BoneIOSR Journals
Cancellous bones from twenty five live tissue donors were tested for bacterial contamination and initial bioburden ranged from 4.1×101 to 3.1×103 cfu/g (average 9.0×102 cfu/g). Forty six representative bacterial isolates were characterized on the basis of morphological, cultural and biochemical characteristics. Staphylococcus spp. was found to be predominant contaminant in tissue samples (41.30%). To assess the radiation resistance all the bacterial isolates were exposed to 1 to 10 kGy gamma radiation from 60Co gamma source. The radiation decimal reduction dose values (D10) and twelve log reduction values (12 D value) of the isolates were calculated. D10 values of the isolates were ranged from 0.59 to 1.20 kGy. Among the studied bacterial isolates, Streptococcus spp. was the most radioresistant isolates (D10 value 0.93-1.20 kGy) and three of the Streptococcus spp. survived up to 8 kGy. All the bacterial isolates were killed at 9 kGy. Twelve log reduction value (12D value) of the most resistant isolate was 14.4 kGy. These results indicate that standard radiation sterilization dose (25 kGy) is satisfactory for the sterilization of the cancellous bone allografts
This document reports on the first evidence that Correia Repeat Enclosed Elements (CREE), which resemble insertion sequence elements in Neisseria gonorrhoeae, can move via inversion within the bacterial genome. Analysis of whole genome sequencing data from N. gonorrhoeae cultured under normal and stress conditions for 8 weeks found 38 CREE that had inverted orientation compared to the reference genome. Inversions occurred more frequently under stress. The inversions provide evidence that CREE can mobilize within the chromosome via inversion rather than translocation. Some inverted CREE were found to contain promoters, suggesting inversion may regulate gene expression.
1) Xenopus laevis oocytes exposed to amyloid-β aggregate developed oscillatory electric activity (blips) recorded via two-microelectrode voltage clamp.
2) The blips increased in amplitude over time from 3.8 nA initially to 6.8 nA after 15 minutes of amyloid-β aggregate exposure, similar to the effects of channel-forming agents amphotericin B and gramicidin.
3) The amyloid-β aggregate-induced currents were dependent on extracellular calcium and disrupted calcium-dependent currents between oocytes and surrounding follicular cells. Electron microscopy also revealed dissociation of follicular cells from the oocytes.
This document summarizes the expression of recombinant β-lactoglobulin (rBLG) in prokaryotic and eukaryotic cells. In Escherichia coli, rBLG was expressed with a pET26 vector and was found predominantly in a denatured form, even when expressed in the periplasm. In eukaryotic cells like COS-7 and mouse tibialis muscle, rBLG was expressed in its native conformation. The authors quantified rBLG expression using immunoassays that distinguish between native and denatured rBLG. They found higher expression levels and native folding of rBLG in eukaryotic systems compared to prokaryotic expression
This document discusses the multifunctional roles of antimicrobial polypeptides in innate immunity. While initially studied for their antibacterial properties, these polypeptides are now recognized to have diverse inflammatory and immunomodulatory functions. For example, the cathelicidin LL-37/hCAP-18 induces angiogenesis in addition to its antimicrobial activity. The discovery of additional functions raises new questions about using these polypeptides therapeutically given their potential effects on multiple biological pathways. Defining their precise roles in vivo remains an ongoing challenge due to the complex interplay of factors in natural infections.
This document summarizes a study that investigated how mechanical forces applied to integrin receptors control intracellular signaling in osteoblasts. The researchers found that cyclic forces applied to the beta-1 integrin subunit at 1 Hz were more effective at stimulating calcium responses in osteoblasts than continuous forces. Cyclic forces also induced increased tyrosine phosphorylation of cytoskeleton-anchored proteins and greater activation of focal adhesion kinase and mitogen-activated protein kinase compared to continuous forces. These responses depended on an intact cytoskeleton and the presence of intracellular calcium. Analysis of spatial calcium signals revealed they originated near the stressed receptors, indicating cells can sense local stress via integrins.
Comparison of 7 Epithermal Neutron Beamskent.riley
This document compares the dosimetric characteristics of seven epithermal neutron beams used for boron neutron capture therapy (BNCT) clinical trials in Sweden, Finland, Czech Republic, Netherlands, and United States. Measurements were taken of neutron fluence and absorbed dose in air and in a water phantom using standardized methods. Results showed the fast neutron and photon contamination levels varied between facilities, as did the epithermal neutron flux intensities available. However, penetration depth was sufficient (>8 cm) for treating brain lesions at the midline for all beams. The data provide the first consistent measurement of beam performance across centers and will help normalize calculated patient dosimetry between facilities.
Boronated Monoclonal Antibody LA84 for BNCTkent.riley
1) The study evaluated a boronated monoclonal antibody (BD-L8A4) that targets the EGFRvIII receptor for the treatment of EGFRvIII-positive rat glioma (F98npEGFRvIII) using boron neutron capture therapy (BNCT).
2) Biodistribution studies found higher retention of BD-L8A4 in EGFRvIII-positive tumors compared to negative tumors after 24 hours.
3) BNCT studies then showed that F98npEGFRvIII-bearing rats treated with BD-L8A4 alone or with boronophenylalanine (BPA) had significantly prolonged survival compared to controls, with some rats
This study evaluated the effectiveness of a 3-carboranyl thymidine analogue (3CTA), designated N5–2OH, as a boron delivery agent for boron neutron capture therapy (BNCT) of brain tumors. Target validation studies using wild-type and mutant thymidine kinase 1 (TK1) L929 cell lines implanted in mice found higher boron levels and tumor cell kill in TK1-expressing tumors after BNCT with N5–2OH. Subsequent studies in rats with intracerebral RG2 gliomas found significantly increased survival times when tumors were treated with either N5–2OH alone or combined with boronophenylalanine compared to boronophenyl
Performance Characteristics of the MIT Epithermal Neutron Irradiation Facilitykent.riley
This document summarizes the performance characteristics of the first fission converter-based epithermal neutron beam (FCB) designed for boron neutron capture therapy (BNCT) at the Massachusetts Institute of Technology (MIT). Key findings include:
1) The FCB provides an epithermal neutron flux of 4.6 × 109 n cm-2 s-1, making it the most intense BNCT source in the world. It achieves low specific photon and fast neutron absorbed doses.
2) Measurements confirm the beam achieves a therapeutic dose rate of 1.7 RBE Gy min-1 at a depth of 97 mm using boronated phenylalanine, with an average therapeutic ratio of
Boronated Cetuximab CCR tumor targeting in BNCTkent.riley
This document describes a study evaluating boronated cetuximab (BD-C225) for boron neutron capture therapy (BNCT) of epidermal growth factor receptor (EGFR) positive gliomas. In vitro, BD-C225 showed preferential uptake in EGFR positive glioma cells compared to EGFR negative cells. In vivo, rats with EGFR positive glioma tumors received intracerebral BD-C225, achieving high boron levels in the tumors. BNCT with BD-C225 alone or combined with boronophenylalanine extended survival compared to controls. The results provide support for using molecularly targeted boron delivery agents like BD-C225 for BNCT of brain tumors.
MIT User Center for Neutron Capture Therapy Resarchkent.riley
The MIT User Center for Neutron Capture Therapy Research provides specialized facilities and capabilities to support preclinical and clinical research in neutron capture therapy (NCT). The Center has two neutron beam facilities located at the Massachusetts Institute of Technology Research Reactor - a thermal neutron beam well-suited for small animal and cell culture studies, and an epithermal beam for clinical studies. Researchers can access these beams as well as capabilities like boron analysis, dosimetry, cell and animal research labs. The Center aims to support the widespread international effort to develop NCT as an effective cancer treatment.
The document reports on progress made in the second year of research reactor coalitions established with IAEA support. It discusses the activities and results of coalitions in Eastern Europe, Eurasia, the Caribbean, and the Mediterranean region. Upcoming initiatives include new coalitions for Africa, the Baltic region, and the Pacific, as well as continued efforts to strengthen existing coalitions through training, workshops, and business planning to promote self-sufficiency. While successes have been achieved, substantial work remains to fully realize the goal of establishing self-sustaining research reactor coalitions.
This study examined the potential protective effects of mesenchymal stem cell (MSC) therapy against cisplatin-induced nephrotoxicity in rats. Rats were treated with cisplatin to induce kidney damage and divided into groups that received either MSCs or no additional treatment. Kidney tissue was analyzed histologically and biochemically after 4 weeks. Cisplatin caused significant kidney damage including atrophied glomeruli, thickened membranes, and tubule damage. It also increased serum markers of kidney injury and electrolyte levels. Rats treated with MSCs after cisplatin showed substantially reduced kidney damage on histology and ultrastructure. Biochemical markers and electrolyte levels were also largely restored to normal
This document discusses materials and methods used in a study involving the chemical fipronil and zinc. Twenty male albino rats were divided into four groups of five rats each: a control group, a zinc group that received zinc supplementation, a fipronil group exposed to the insecticide fipronil, and a combination group exposed to both zinc and fipronil. Biochemical assays were conducted to assess oxidative stress markers like superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione, lipid peroxidation, and total protein in the rats. Chemicals used including fipronil and zinc sulfate were obtained from reputable suppliers. Kits for the biochemical assays were purchased from a diagnostic
This document provides an overview of the perforated patch-clamp technique, including:
- The rationale for using perforated patch-clamp is to overcome the dialysis of intracellular components that occurs with traditional whole-cell recording.
- Common perforants like nystatin and amphotericin B form small pores that allow electrical access while preventing diffusion of larger molecules.
- Gramicidin is also used and has the advantage of preserving intracellular chloride concentration.
- Step-by-step guidance is given for performing recordings with nystatin, amphotericin B, and gramicidin. Progress of perforation is monitored by observing changing current responses to voltage pulses.
This document describes a study that used fiber optic confocal imaging (FOCI) to examine changes in the colonic microvasculature and morphology in a rat model of ulcerative colitis. Rats were given dextran sulfate sodium (DSS) in their drinking water to induce mild colitis, and were examined using FOCI after 3, 5, and 7 days. FOCI using tetracycline hydrochloride staining showed attenuation of the colonic epithelium by day 3 and crypt distortion and inflammatory cell infiltrate by days 5 and 7. Dual staining with FITC-dextran revealed increased vascularity, tortuosity and leakage by day 5, and disrupted vascular patterns by day 7. The findings
Protein corona associated with nanoparticlesANJUNITHIKURUP
The document discusses protein coronas that form around nanoparticles when introduced into biological fluids and how they impact physiological response. It summarizes that nanoparticles interact with proteins to form complexes with unique identities compared to the original nanoparticle. These complexes determine responses like uptake, circulation and toxicity. The document then examines several studies that show how nanoparticle properties like size and surface chemistry influence protein adsorption and subsequently impact biological response. It also reviews techniques for characterizing and experimentally investigating protein coronas and their effects.
Nano-crystalline cellulose (NCC) was tested on various bacterial species to investigate its effect on bacterial viability. NCC was found to decrease viability for dilute suspensions of E. coli B and S. aureus based on membrane integrity assays, but did not significantly decrease viability for concentrated suspensions or other bacterial species. Metabolic activity assays also showed no significant decrease in activity for bacteria exposed to NCC. While NCC exposure had some effect on membrane integrity of certain bacteria, it did not strongly impact overall viability or metabolic function across the species tested.
This case report describes a 70-year-old female diagnosed with gastric adenocarcinoma with osteoclast-like giant cells (OGCs). Histopathological examination revealed a moderately differentiated adenocarcinoma with prominent lympho-histocytic infiltration and OGCs in the stroma. Immunohistochemistry showed the tumor cells were positive for pancytokeratin and the OGCs were positive for CD68. Additionally, the tumor and lymph nodes were positive for Epstein-Barr virus. The authors conclude that gastric carcinomas with OGCs are rare tumors that must be distinguished from more aggressive anaplastic carcinomas.
This document summarizes a study investigating the epigenetic changes that occur during the transdifferentiation of pancreatic acinar cells (HPACs) to hepatocyte-like cells. The study found that DNA methylation in HPACs peaks at 24 hours after treatment with dexamethasone, and the cells display phenotypic changes associated with hepatocytes after 7 days. The study also examined the promoter sequence of the SGK1 gene, which is involved in the transdifferentiation process. The results suggest therapeutic potential for producing hepatocytes from pancreatic cells to treat liver disease in a more cost-effective manner than current alternatives.
The document discusses several cases of glomerular disease:
1) A 27-year-old male with nephrotic syndrome and a kidney biopsy showing IgG and C3 deposits along the glomerular basement membrane consistent with membranous nephropathy.
2) A 78-year-old female admitted with nephrotic syndrome after a history of NSAID use, with a biopsy showing focal segmental glomerulosclerosis.
3) A 26-year-old male with nephrotic syndrome and renal impairment, whose biopsy demonstrated membranoproliferative glomerulonephritis with C3 deposition and subendothelial electron dense deposits. Follow up showed elevated
Veropaque, a novel contrast agent containing iohexol and a substituted cyclodextrin (SCD), was shown to significantly reduce contrast-induced acute kidney injury (CI-AKI) in preclinical studies compared to iohexol alone. In mouse and rat models, Veropaque demonstrated reduced kidney pathology scores and preserved kidney function as measured by plasma creatinine levels. A dog study found Veropaque caused no differences in cardiovascular effects from intracoronary injection of iohexol alone. The SCD was able to protect the kidney from multiple contrast agents, suggesting a mechanism beyond complexation of the contrast. Based on these findings, the authors believe Veropaque has potential to decrease CI-AKI
Kupffer Cells Mediate Leptin-Induced Liver Fibrosis.
GASTROENTEROLOGY 2009;137:713–723
JIANHUA WANG,* ISABELLE LECLERCQ,‡ JOANNE M. BRYMORA,* NING XU,* MEHDI RAMEZANI–MOGHADAM,* ROSLYN M. LONDON,* DAVID BRIGSTOCK,§ and JACOB GEORGE*
*Storr Liver Unit, Westmead Millennium Institute, University of Sydney and Westmead Hospital, Westmead, Australia; ‡Laboratory of Gastroenterology, Faculty of
Medicine, Université Catholique de Louvain, Brussels, Belgium; and §Center for Cell and Vascular Biology, Children’s Research Institute, Columbus, Ohio
瘦素(Leptin)是一由脂肪細胞(Adipocyte)所分泌之荷爾蒙,是調控體重及新陳代謝之重要因子。過去研究發現病態肥胖(Obese)、脂肪肝(Nonalcoholic steatohepatitis)及酒精性肝炎(Alcoholic liver disease)等病患之血液循環中,Leptin量有明顯增加。而近期研究報告指出leptin具有促進肝臟纖維化(Liver fibrosis)之能力,當中分子機理並未明確。
在肝纖維化過程中,肝臟星狀細胞(HSC)會被活化增生及促進胞外基質(ECM)產生,而鄰近之Kupffer細胞(KC)則已知可透過促發炎因子(Proinflammatory factor)和促纖維化因子(Profibrogenic factors)例如TGF-β1和ROS影響HSC表現。雖然HSC是肝纖維化過程中重要角色,前人研究卻發現leptin似對HSC無任何調控作用。故本篇作者針對Leptin是否透過間接作用於HSC鄰近之KC,刺激其產生促纖維化因子,以活化HSC。
為探討leptin直接或間接影響HSC之分子機理,本篇作者透過RT-PCR、Immunoblot等分子生物學方法,分別測定leptin刺激後HSC及KC中Collagen I、TIMP1等促纖維化因子基因及蛋白表現,發現leptin雖可促使HSC增生,但對其纖維化能力之影響甚微。而leptin可刺激KC中TGF-β1及CTGF/CCN2等肝纖維化中重要之cytokines表現。另發現Leptin-treated KC-conditioned培養液可刺激HSC增生及增加其中Collagen I、TIMP1等表現,得出了leptin是透過刺激KC來活化HSC之推論。作者亦於後續實驗中,透過磷酸化測定、EMSA等方法探討leptin訊號傳遞作用,發現leptin可活化KC中STAT3、ERK1/2、AKT等路徑,及下游因子AP-1、NF-κB,而此兩種蛋白具有增強TGF-β1及CTGF/CCN2基因表現之能力。
Biolostic transformation of a procaryote, bacillus megateriumCAS0609
This document describes a new method for transforming the bacterium Bacillus megaterium using biolistic transformation. Key findings include:
1) Plasmid DNA was coated onto tungsten microprojectiles and accelerated into B. megaterium cells using a helium-driven biolistic device.
2) Over 104 transformants per treated plate were obtained after optimizing biological and physical parameters of the biolistic process.
3) All strains of B. megaterium tested were successfully transformed, though efficiency varied between strains. This is the first report of biolistic transformation of a prokaryote.
The document summarizes research on using statins and ezetimibe to prevent atherosclerosis by lowering LDL levels. Clinical trials showed that while ezetimibe further lowered LDL when added to statin therapy, it did not significantly reduce atherosclerosis on its own. However, a 2011 study found that patients taking simvastatin and ezetimibe saw greater reduction in plaque volume over 2 years compared to simvastatin or ezetimibe alone. The research suggests combining statins with ezetimibe may provide benefits for preventing atherosclerosis beyond statins alone.
The effects of diethylstilbestrol administration on rat kidney. ultrastructur...Prof. Hesham N. Mustafa
This study examined the effects of diethylstilbestrol (DES) administration on rat kidney tissues over different time periods using histological, immunohistochemical, and ultrastructural analysis. Thirty male rats were divided into three groups: a control group, a group that received 60 μg/kg DES daily for 20 days, and a group that received the same dose of DES for 50 days. DES administration for 50 days caused degeneration of renal tissues, damage to renal tubules, increased cellularity of glomeruli, and a significant increase in BAX protein expression, indicating increased apoptosis. These changes were less pronounced after 20 days of treatment. The study found that non-steroidal synthetic estrogens like DES can have
Borane V R*
Department of Zoology Jijamata Arts, Science and Commerce College, Nandurbar, Maharashtra, India
ABSTRACT- The present investigation was carried out to the effect of Dimethoate on histopathological changes in liver
of freshwater fish, Garra mullya using standard methods. Fish was exposed to sub lethal concentration of Dimethoate
(0.0238ppm of 96hrs) for 7, 14, and 21days. Administration of pesticide to determine lesion of liver as indicators of tissue
damage. Histopathological changes in liver ranged from vacuolization, necrosis, fibrosis of perivascular region and
disposition of yellow brown grains at different time of exposure. Liver histology exhibited various abnormalities,
including hyperplasia, nuclear pyknosis, fatty necrosis and degeneration of hepatocytes leading to tumor and syncytium
formation, which are the indicative of carcinogenesis. In chronic treatment of dimethoate exposure may pose serious
threat to fish health and affect their population.
Key-words- Dimethoate, Histopathology, Liver, Garra mullya
This document describes the development of a novel fluorescent protein-based sensor for detecting 2-oxoglutarate (2OG) levels in living cells. The sensor, termed mOGsor, was created by inserting the 2OG-binding domain GAF from the NifA protein into yellow fluorescent protein (YFP). mOGsor exhibits increased fluorescence intensity upon binding to 2OG in a concentration-dependent manner. Testing showed mOGsor has high specificity for 2OG and fast kinetics. Using mOGsor, the authors were able to monitor real-time changes in 2OG levels in E. coli cells under different nutrient conditions. mOGsor represents an improvement over previous FRET-based 2OG sensors by providing a
This document discusses calprotectin (CP) and its role in gastrointestinal (GI) inflammation. CP is a biomarker for inflammatory bowel disease (IBD) that is stable, reproducible to assay, and low cost. As an antimicrobial protein released by neutrophils during tissue inflammation, CP fuels and propagates mucosal inflammation through various effects, including chemotaxis and modulation of the immune response. CP levels can increase in conditions other than IBD such as infections, malignancies, and drug reactions, so clinical evaluation is still needed when levels are intermediate or elevated. Further study of CP, especially its subunits S100A8 and S100A9, may lead to new diagnostic and therapeutic approaches for managing IBD
The document provides an introduction to the anatomy and physiology of the liver and rodent stomach. It covers the basic structure of the liver including the hepatic circulation, liver lobule, and liver acinus. It describes the key cell types in the liver including hepatocytes, Kupffer cells, pit cells, and Ito cells. It also discusses the liver's role in bile formation and excretion of bilirubin. Finally, it outlines the sections to be covered in the document, including responses of the liver to toxic injury and interpretation of rodent hepatic and stomach tumor data.
This study examined apoptosis of lymphocytes in patients with systemic lupus erythematosus (SLE). The percentage of apoptotic lymphocytes from SLE patients was significantly higher than healthy donors after 36 hours of incubation, indicating SLE patients have more lymphocytes undergoing apoptosis. A positive correlation was also found between lymphocyte apoptosis in SLE and disease activity markers like anti-dsDNA antibodies and prednisolone dosage. The percentage of CD4+ T cells was significantly lower in SLE patients compared to healthy donors.
The study aimed to test the specificity of two antibodies (033 and 1-9E10) for binding the c-myc protein. Human colon carcinoma cells were extracted to obtain cytosolic, nuclear, and nuclear pellet extracts. The 033 antibody bound c-myc in the cytosolic extract at approximately 110 kDa, but the 9E10 antibody did not bind c-myc. This suggests c-myc is not restricted to the nucleus and more research is needed to fully understand c-myc and its role in cancer.
Similar to Selective Irradiation of the Mouse Gut Vasculature (20)
RBE of the MIT clinical epithermal neutron beamkent.riley
This document summarizes a study that determined the relative biological effectiveness (RBE) of an epithermal neutron beam at the Massachusetts Institute of Technology (MIT) using intestinal crypt regeneration in mice. Mice were irradiated with the MIT neutron beam at depths of 2.5 cm and 9.7 cm, receiving absorbed doses between 2.6 and 12.3 Gy over 7 to 62 minutes. Control irradiations using 6 MV photons were also performed. Crypt survival curves were generated and fit using linear-quadratic models to estimate RBE values of 1.50 ± 0.04 at 2.5 cm and 1.03 ± 0.03 at 9.7 cm depth for the neutron beam relative to photons.
Clinical Trials in BNCT at the MIT Research Reactorkent.riley
A phase I clinical trial was conducted to evaluate neutron capture therapy for brain tumors. 24 patients with glioblastoma or melanoma metastases to the brain received boronophenylalanine followed by neutron irradiation. Doses were escalated in cohorts from 8.8 to 14.2 RBE-Gy. The most common side effects were alopecia and temporary increased intracranial pressure. More serious adverse events included respiratory failure in two elderly patients and one treatment-related death. Two patients showed a complete response, and tumor volume decreased in most patients. The trial demonstrated neutron capture therapy can achieve a clinical response with acceptable toxicity.
This document provides a critical review of fission reactor neutron sources for neutron capture therapy (NCT). It summarizes that epithermal neutron beams, favored for treating deep tumors, have been constructed or are being constructed at several reactors worldwide, with some newer beams approaching theoretical optimum purity. At least one such high-quality beam is suitable for routine therapy. Reactor-based epithermal beams with near-optimum characteristics are currently available and more can be constructed. Suitable reactors include low-power reactors using the core directly or a fission converter as the neutron source. Thermal neutron beams have also been available for years with near-optimum properties for small animal studies or shallow tumors.
This document describes a new tissue-equivalent plastic called A-181 that accurately simulates the photon and neutron absorption properties of brain tissue. A-181 was formulated to match the recommended hydrogen and nitrogen content of brain tissue for applications using low-energy neutrons like boron neutron capture therapy (BNCT). Measurements using A-181 and the standard muscle tissue equivalent plastic A-150 in a BNCT beam show good agreement with Monte Carlo calculations and demonstrate A-181's suitability for neutron dosimetry in brain tissue.
1) The study evaluated a boronated monoclonal antibody (BD-L8A4) that targets the EGFRvIII receptor for the treatment of rat glioma tumors expressing EGFRvIII using boron neutron capture therapy (BNCT).
2) Biodistribution studies found that BD-L8A4 accumulated more in EGFRvIII-positive tumors compared to EGFRvIII-negative tumors and boron levels in normal tissues remained low.
3) BNCT studies then found that rats receiving BD-L8A4 alone or with boronophenylalanine (BPA) had significantly longer survival times compared to controls, with some rats experiencing long-term survival or being
Unifying Dose Prescriptions in the Americaskent.riley
1) A dosimetry intercomparison was performed between the boron neutron capture therapy (BNCT) groups at the Massachusetts Institute of Technology (MIT) and Comisión Nacional de Energía Atómica (CNEA) in Argentina to enable combined analysis of patient data between centers.
2) In-air and depth dose measurements were made in a water phantom at the RA-6 reactor hyperthermal neutron beam facility in Bariloche, Argentina.
3) Calculated dose profiles from CNEA's treatment planning system required normalizations of 1.0 for thermal neutrons, 1.13 for photons, and 0.74 for fast neutrons to match dosimetry measurements made by
Radiation Resistance of Teflon as a Filter Moderator Materialkent.riley
This document summarizes the results of irradiating polytetrafluoroethylene (PTFE, also known as Teflon) samples with mixed fields of fast neutrons and gamma rays. Samples were irradiated to doses ranging from 0.3 to 50 million Gy for gamma rays and 0.13 to 80 thousand Gy for fast neutrons. The irradiated samples showed high levels of embrittlement but minimal changes (less than 1.5%) in properties like weight loss, fluorine loss, and swelling even at the highest doses. PTFE appears to have adequate physical and chemical stability for use in neutron filter applications in nuclear reactors.
Lithium Filtration for Improved Dose Penetration in BNCTkent.riley
This document summarizes research into adding an optional 6Li filter to an existing epithermal neutron beam used for boron neutron capture therapy (BNCT) to treat brain tumors. Monte Carlo simulations and measurements were used to design and test a removable 8mm thick 6Li filter. The filter improved penetration of thermal neutrons to depths of 9.9cm while maintaining tumor selectivity. Recalculating past treatment plans showed the filter could increase minimum deliverable tumor doses by up to 9% without increasing normal tissue doses. The filter provides an incremental enhancement to the clinical beam that may help establish a therapeutic window for treating deeper tumors.
A State of the Art Epithermal Neutron Irradiation Facility for BNCTkent.riley
This document summarizes a state-of-the-art epithermal neutron irradiation facility for neutron capture therapy located at the Massachusetts Institute of Technology (MIT). The facility uses a fission converter-based epithermal neutron beam (FCB) that provides a high intensity beam suitable for clinical trials of boron neutron capture therapy (BNCT). The FCB operates independently of other reactor experiments and can deliver irradiation in under 10 minutes with automated monitoring and safety controls. It is part of a larger BNCT program at MIT that also includes a prompt gamma neutron activation analysis facility to measure boron levels in tissues.
1) A variable collimator was designed, constructed, and tested for use in an epithermal neutron beam for boron neutron capture therapy (BNCT) at MIT.
2) The collimator was optimized using Monte Carlo simulations and constructed from a mixture of lead spheres cast in epoxy resin loaded with boron carbide or lithium fluoride to provide neutron shielding.
3) Beam profiles and collateral dose measurements in a half-body phantom demonstrated the collimator provides sufficient shielding and a well-defined, uniform beam suitable for BNCT clinical studies.
The document discusses measuring prompt gamma emission during proton therapy to provide in situ range verification. Experiments were conducted using a 150 MeV proton beam on a PMMA phantom, measuring gamma rays at 90 degrees to the beam axis at different depths. Measurements showed a steady increase in gamma emission through the entrance region, followed by a sharp decline at the Bragg peak, consistent with other studies. Monte Carlo simulations were also performed and agreed with measurements, showing promise for using prompt gamma detection to characterize proton beam range during treatment.
International Dosimetry Exchange for Boron Neutron Capture Therapykent.riley
The document discusses the potential for a more formal collaboration between BNCT clinical centers to collectively analyze clinical outcomes data. It proposes that a coordinated effort could help advance the field by increasing patient statistics, standardizing practices, and facilitating comparisons to other treatments. Previous informal cooperation between centers has been successful, and a more organized international initiative modeling existing efforts like the International Dosimetry Exchange could provide insights to optimize protocols and assess normal tissue tolerances.
QA or the Highway - Component Testing: Bridging the gap between frontend appl...zjhamm304
These are the slides for the presentation, "Component Testing: Bridging the gap between frontend applications" that was presented at QA or the Highway 2024 in Columbus, OH by Zachary Hamm.
Discover top-tier mobile app development services, offering innovative solutions for iOS and Android. Enhance your business with custom, user-friendly mobile applications.
"$10 thousand per minute of downtime: architecture, queues, streaming and fin...Fwdays
Direct losses from downtime in 1 minute = $5-$10 thousand dollars. Reputation is priceless.
As part of the talk, we will consider the architectural strategies necessary for the development of highly loaded fintech solutions. We will focus on using queues and streaming to efficiently work and manage large amounts of data in real-time and to minimize latency.
We will focus special attention on the architectural patterns used in the design of the fintech system, microservices and event-driven architecture, which ensure scalability, fault tolerance, and consistency of the entire system.
"Choosing proper type of scaling", Olena SyrotaFwdays
Imagine an IoT processing system that is already quite mature and production-ready and for which client coverage is growing and scaling and performance aspects are life and death questions. The system has Redis, MongoDB, and stream processing based on ksqldb. In this talk, firstly, we will analyze scaling approaches and then select the proper ones for our system.
In the realm of cybersecurity, offensive security practices act as a critical shield. By simulating real-world attacks in a controlled environment, these techniques expose vulnerabilities before malicious actors can exploit them. This proactive approach allows manufacturers to identify and fix weaknesses, significantly enhancing system security.
This presentation delves into the development of a system designed to mimic Galileo's Open Service signal using software-defined radio (SDR) technology. We'll begin with a foundational overview of both Global Navigation Satellite Systems (GNSS) and the intricacies of digital signal processing.
The presentation culminates in a live demonstration. We'll showcase the manipulation of Galileo's Open Service pilot signal, simulating an attack on various software and hardware systems. This practical demonstration serves to highlight the potential consequences of unaddressed vulnerabilities, emphasizing the importance of offensive security practices in safeguarding critical infrastructure.
This talk will cover ScyllaDB Architecture from the cluster-level view and zoom in on data distribution and internal node architecture. In the process, we will learn the secret sauce used to get ScyllaDB's high availability and superior performance. We will also touch on the upcoming changes to ScyllaDB architecture, moving to strongly consistent metadata and tablets.
High performance Serverless Java on AWS- GoTo Amsterdam 2024Vadym Kazulkin
Java is for many years one of the most popular programming languages, but it used to have hard times in the Serverless community. Java is known for its high cold start times and high memory footprint, comparing to other programming languages like Node.js and Python. In this talk I'll look at the general best practices and techniques we can use to decrease memory consumption, cold start times for Java Serverless development on AWS including GraalVM (Native Image) and AWS own offering SnapStart based on Firecracker microVM snapshot and restore and CRaC (Coordinated Restore at Checkpoint) runtime hooks. I'll also provide a lot of benchmarking on Lambda functions trying out various deployment package sizes, Lambda memory settings, Java compilation options and HTTP (a)synchronous clients and measure their impact on cold and warm start times.
"NATO Hackathon Winner: AI-Powered Drug Search", Taras KlobaFwdays
This is a session that details how PostgreSQL's features and Azure AI Services can be effectively used to significantly enhance the search functionality in any application.
In this session, we'll share insights on how we used PostgreSQL to facilitate precise searches across multiple fields in our mobile application. The techniques include using LIKE and ILIKE operators and integrating a trigram-based search to handle potential misspellings, thereby increasing the search accuracy.
We'll also discuss how the azure_ai extension on PostgreSQL databases in Azure and Azure AI Services were utilized to create vectors from user input, a feature beneficial when users wish to find specific items based on text prompts. While our application's case study involves a drug search, the techniques and principles shared in this session can be adapted to improve search functionality in a wide range of applications. Join us to learn how PostgreSQL and Azure AI can be harnessed to enhance your application's search capability.
zkStudyClub - LatticeFold: A Lattice-based Folding Scheme and its Application...Alex Pruden
Folding is a recent technique for building efficient recursive SNARKs. Several elegant folding protocols have been proposed, such as Nova, Supernova, Hypernova, Protostar, and others. However, all of them rely on an additively homomorphic commitment scheme based on discrete log, and are therefore not post-quantum secure. In this work we present LatticeFold, the first lattice-based folding protocol based on the Module SIS problem. This folding protocol naturally leads to an efficient recursive lattice-based SNARK and an efficient PCD scheme. LatticeFold supports folding low-degree relations, such as R1CS, as well as high-degree relations, such as CCS. The key challenge is to construct a secure folding protocol that works with the Ajtai commitment scheme. The difficulty, is ensuring that extracted witnesses are low norm through many rounds of folding. We present a novel technique using the sumcheck protocol to ensure that extracted witnesses are always low norm no matter how many rounds of folding are used. Our evaluation of the final proof system suggests that it is as performant as Hypernova, while providing post-quantum security.
Paper Link: https://eprint.iacr.org/2024/257
What is an RPA CoE? Session 1 – CoE VisionDianaGray10
In the first session, we will review the organization's vision and how this has an impact on the COE Structure.
Topics covered:
• The role of a steering committee
• How do the organization’s priorities determine CoE Structure?
Speaker:
Chris Bolin, Senior Intelligent Automation Architect Anika Systems
The Department of Veteran Affairs (VA) invited Taylor Paschal, Knowledge & Information Management Consultant at Enterprise Knowledge, to speak at a Knowledge Management Lunch and Learn hosted on June 12, 2024. All Office of Administration staff were invited to attend and received professional development credit for participating in the voluntary event.
The objectives of the Lunch and Learn presentation were to:
- Review what KM ‘is’ and ‘isn’t’
- Understand the value of KM and the benefits of engaging
- Define and reflect on your “what’s in it for me?”
- Share actionable ways you can participate in Knowledge - - Capture & Transfer
inQuba Webinar Mastering Customer Journey Management with Dr Graham HillLizaNolte
HERE IS YOUR WEBINAR CONTENT! 'Mastering Customer Journey Management with Dr. Graham Hill'. We hope you find the webinar recording both insightful and enjoyable.
In this webinar, we explored essential aspects of Customer Journey Management and personalization. Here’s a summary of the key insights and topics discussed:
Key Takeaways:
Understanding the Customer Journey: Dr. Hill emphasized the importance of mapping and understanding the complete customer journey to identify touchpoints and opportunities for improvement.
Personalization Strategies: We discussed how to leverage data and insights to create personalized experiences that resonate with customers.
Technology Integration: Insights were shared on how inQuba’s advanced technology can streamline customer interactions and drive operational efficiency.
Essentials of Automations: Exploring Attributes & Automation ParametersSafe Software
Building automations in FME Flow can save time, money, and help businesses scale by eliminating data silos and providing data to stakeholders in real-time. One essential component to orchestrating complex automations is the use of attributes & automation parameters (both formerly known as “keys”). In fact, it’s unlikely you’ll ever build an Automation without using these components, but what exactly are they?
Attributes & automation parameters enable the automation author to pass data values from one automation component to the next. During this webinar, our FME Flow Specialists will cover leveraging the three types of these output attributes & parameters in FME Flow: Event, Custom, and Automation. As a bonus, they’ll also be making use of the Split-Merge Block functionality.
You’ll leave this webinar with a better understanding of how to maximize the potential of automations by making use of attributes & automation parameters, with the ultimate goal of setting your enterprise integration workflows up on autopilot.
Dandelion Hashtable: beyond billion requests per second on a commodity serverAntonios Katsarakis
This slide deck presents DLHT, a concurrent in-memory hashtable. Despite efforts to optimize hashtables, that go as far as sacrificing core functionality, state-of-the-art designs still incur multiple memory accesses per request and block request processing in three cases. First, most hashtables block while waiting for data to be retrieved from memory. Second, open-addressing designs, which represent the current state-of-the-art, either cannot free index slots on deletes or must block all requests to do so. Third, index resizes block every request until all objects are copied to the new index. Defying folklore wisdom, DLHT forgoes open-addressing and adopts a fully-featured and memory-aware closed-addressing design based on bounded cache-line-chaining. This design offers lock-free index operations and deletes that free slots instantly, (2) completes most requests with a single memory access, (3) utilizes software prefetching to hide memory latencies, and (4) employs a novel non-blocking and parallel resizing. In a commodity server and a memory-resident workload, DLHT surpasses 1.6B requests per second and provides 3.5x (12x) the throughput of the state-of-the-art closed-addressing (open-addressing) resizable hashtable on Gets (Deletes).
Connector Corner: Seamlessly power UiPath Apps, GenAI with prebuilt connectorsDianaGray10
Join us to learn how UiPath Apps can directly and easily interact with prebuilt connectors via Integration Service--including Salesforce, ServiceNow, Open GenAI, and more.
The best part is you can achieve this without building a custom workflow! Say goodbye to the hassle of using separate automations to call APIs. By seamlessly integrating within App Studio, you can now easily streamline your workflow, while gaining direct access to our Connector Catalog of popular applications.
We’ll discuss and demo the benefits of UiPath Apps and connectors including:
Creating a compelling user experience for any software, without the limitations of APIs.
Accelerating the app creation process, saving time and effort
Enjoying high-performance CRUD (create, read, update, delete) operations, for
seamless data management.
Speakers:
Russell Alfeche, Technology Leader, RPA at qBotic and UiPath MVP
Charlie Greenberg, host
LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...DanBrown980551
This LF Energy webinar took place June 20, 2024. It featured:
-Alex Thornton, LF Energy
-Hallie Cramer, Google
-Daniel Roesler, UtilityAPI
-Henry Richardson, WattTime
In response to the urgency and scale required to effectively address climate change, open source solutions offer significant potential for driving innovation and progress. Currently, there is a growing demand for standardization and interoperability in energy data and modeling. Open source standards and specifications within the energy sector can also alleviate challenges associated with data fragmentation, transparency, and accessibility. At the same time, it is crucial to consider privacy and security concerns throughout the development of open source platforms.
This webinar will delve into the motivations behind establishing LF Energy’s Carbon Data Specification Consortium. It will provide an overview of the draft specifications and the ongoing progress made by the respective working groups.
Three primary specifications will be discussed:
-Discovery and client registration, emphasizing transparent processes and secure and private access
-Customer data, centering around customer tariffs, bills, energy usage, and full consumption disclosure
-Power systems data, focusing on grid data, inclusive of transmission and distribution networks, generation, intergrid power flows, and market settlement data
2. Table 1. Beam doses, total blood doses, and endothelial cell
doses used in the survival experiments
Beam-only 10B in blood,* Total blood Endothelial cell
dose, Gy g g 10B dose,† Gy dose,‡ Gy
5.7 0.4 45 7 20.9 1.0 10.8 0.9
7.5 0.5 118 12 60.1 5.7 25.0 2.0
8.3 0.6 118 12 66.5 6.3 27.7 2.2
9.0 0.6 0 9.0 0.6 9.0 0.6
10.0 0.7 0 10.0 0.7 10.0 0.7
*MAC liposomes or MAC TAC liposomes were used to produce 45 7 or
118 12 g g 10B in the blood, respectively.
Fig. 1. 10B concentrations in blood and tissues as a function of time after †Total blood dose is the beam dose plus the 10B dose to the blood.
injection of 0.2 ml of the MAC liposome preparation into the retroorbital ‡Endothelial cell dose is the beam dose plus one-third of the 10B dose to the
sinus. Points represent the mean SD (n 5 mice per time point). blood.
concentrations in liver, skin, and small intestine were 18 2, the uncertainty in the neutron beam dosimetry as well as the
3.7 0.2, and 0.6 1.0 g g 10B, respectively. The low boron uncertainty in the blood–boron concentration at the time of
concentrations observed in the skin and intestine are most likely irradiation.
due to the blood content of the tissue samples analyzed. The time
of irradiation was chosen as 30 min after injection based on the Intestinal Crypt Regeneration Assay. The numbers of regenerating
boron biodistribution and the logistical reasons associated with crypts per intestinal cross section as a function of the physical
the reactor irradiations. The solution containing liposomes with absorbed doses from the epithermal neutron beam are shown in
MAC in the lipid bilayer and [B20H17NH3]3 (TAC) in the Fig. 2 for the four experimental groups (epithermal neutron
interior (MAC TAC) was used to provide a higher blood– beam only, irradiation with the MAC liposomes in the blood,
boron concentration. Eight additional mice received a 0.2-ml irradiation with the MAC TAC liposomes in the blood, or the
injection of the MAC TAC liposome preparation and were BPA positive control). The crypt regeneration data points for the
killed at 30 min after injection. The 10B concentrations in blood, two groups that received liposome injections and beam doses of
liver, and small intestine were 118 12, 61 3, and 0.54 0.49 6 Gy were within one standard deviation of the exponential fit
g g 10B, respectively. As expected, the blood–boron concen- to the beam-only dose–response data (Fig. 2) despite the pres-
tration scaled proportionately with the increased boron content ence of 45 7 or 118 12 g g 10B in the blood and estimated
in the MAC TAC liposome solution. The boron concentration endothelial cell doses that were 2- or 3-fold higher than the
in the small intestine was below the prompt gamma neutron whole-body beam doses (Table 1). Regression fits of the beam-
activation analysis detection limit, as was the case for the MAC only and the beam-plus-liposome data in the linear region of the
liposomes. dose–response relationship indicate that absorbed doses of 7.3
A time point 2 hr after injection was chosen for the p- 0.6 Gy (beam only), 7.2 0.6 Gy (beam plus MAC), and 7.1
boronophenylalanine (BPA) biodistribution study to allow the 0.6 Gy (beam plus MAC TAC) were required to reduce crypt
boron to equilibrate from the blood into the normal tissues. The stem cell survival to the level of 20 regenerating crypts per
10B concentrations in blood and small intestine were 13.7 4.6 circumference. The added absorbed dose selectively delivered to
and 13.0 3.6 g g 10B, respectively (n 5). the vascular endothelial cells in the beam-plus-liposome groups
did not contribute to intestinal crypt stem cell depletion. Lipo-
Dosimetry. The total absorbed dose rate in the epithermal some injections with no neutron irradiation had no effect on
neutron beam was 0.57 0.04 Gy min 1 at a depth of 2.5 cm and crypt regeneration numbers compared with the nontreated
was composed of 77% low-linear energy transfer (LET) photons controls.
and 23% high-LET radiations, which are principally protons The data shown in Fig. 2 are in good agreement with the data
arising from thermal neutron capture in nitrogen. The relative
uncertainty on the neutron beam doses was 2.2%, which includes
only the statistical uncertainty in the beam monitor counts and
variations of 1 mm in the positioning of the irradiation jig along
the center of the beam’s central axis. The additional absorbed
dose rate from the 10B capture reaction was 3.3 0.18 cGy min 1
per g of 10B present.
The total absorbed dose rate in the vascular endothelial cells,
with boronated liposomes in the blood at the time of neutron
irradiation, was estimated as the sum of the whole-body neutron
beam absorbed dose rate plus one-third of the 10B absorbed dose
rate in the blood (Table 1). The additional absorbed dose rate
in the microvasculature coming from boron neutron capture
reactions in the blood was 1.1 0.06 cGy min 1 per g of 10B,
which includes the geometrical factor of one-third (13). The
higher 10B concentration in the blood associated with the
Fig. 2. Number of regenerating crypts per intestinal circumference as a
MAC TAC liposomes allowed the dose to the vascular endo-
function of neutron beam dose 84 1 h after whole-body irradiation in the
thelial cells to be increased while all other parameters were held presence or absence of boronated liposomes in the blood or with a uniform 10B
constant. Thus, the total absorbed dose rate in the microvascu- distribution using BPA. The triangles and squares represent irradiation con-
lature was 1.08 0.09 or 1.90 0.16 Gy min 1 with 45 7 or ditions where the dose to the microvasculature was increased relative to the
118 12 g g 10B in the blood, respectively. The stated rest of the mouse by a factor of 2 or 3, respectively. Points represent the
uncertainties on the microvascular absorbed dose rates include mean SD of at least 16 jejunal cross sections, 4 sections from each of 4 mice.
3788 www.pnas.org cgi doi 10.1073 pnas.0600133103 Schuller et al.
3. of Gueulette et al. (14) in the same mouse (BALB c) with the
same irradiation jig and geometry in the same neutron beam. In
that study (14), the epithermal neutron beam at the Massachu-
setts Institute of Technology Nuclear Reactor Laboratory was
shown to have a relative biological effectiveness of 1.5 0.04,
relative to 6-MV photons, for the crypt regeneration endpoint.
Thus, the neutron beam absorbed doses of 3.2–10.0 Gy used
here, which are a mix of high- and low-LET radiations, corre-
spond to photon-equivalent doses of 4.8–15.0 Gy for the crypt
survival endpoint. Fig. 2 shows that there were 10 regenerating
crypts per circumference for an absorbed dose of 8.3 Gy (a
12.5-Gy photon equivalent), which is consistent with this dose
being near the threshold for a GI death.
The number of regenerating crypts per intestinal cross section
after neutron irradiation in the presence of a uniform 10B
concentration in blood and intestine, as delivered by BPA, is also
shown in Fig. 2. The intent of this BPA positive control exper-
iment was to estimate the sensitivity of the crypt regeneration
assay for the detection of potential 10B diffusion out of the
vessels. The presence of 13 g g 10B in both blood and
intestine increased the physical absorbed dose rate by 75%, an
additional 0.43 Gy min 1. The BPA positive control dose–
response curve is shifted significantly to the left when plotted Fig. 3. Survival experiments. (A) Mouse survival after whole-body, neutron-
versus the beam dose (Fig. 2). Based on these data, we estimate beam-only irradiations. (B) Mouse survival after whole-body neutron irradi-
that the crypt regeneration assay could detect the effect of the ation with boronated liposomes present in the blood. The microvascular
added 10B dose from as little as 2 g g 10B outside the vessels, absorbed doses were 10.8 0.9 (MAC), 25.0 2.0 (MAC TAC), and 27.7 2.2
which represents a 2% ‘‘leakage’’ of the MAC TAC blood– Gy (MAC TAC), respectively.
boron concentration.
Even with all 10B restricted to the vessel lumen, the ranges of
the alpha (9 m) and lithium particles (5 m) are such that some stem cells (Table 1). In the 5.7-Gy beam plus MAC group, 11 of
dose will be absorbed outside of the vessel wall. Monte Carlo 12 mice lived beyond 30 d, whereas all mice (n 10) in the 7.5-Gy
simulations show that the 10B dose gradient outside the vessel beam plus MAC TAC group and all mice (n 8) in the 8.3-Gy
drops off steeply. For example, for the 8.3-Gy beam dose with the beam plus MAC TAC group died within 6–7 d. Fig. 4 shows
MAC TAC liposomes (118 g g 10B in the blood) (Table 1), the hematoxylin-and-eosin-stained small intestine (jejunum) and
absorbed 10B dose to the blood inside the vessel lumen is 58.2 Gy. bone marrow sections from a mouse in the 8.3-Gy beam plus
Outside the vessel, at distances of 2, 5, and 7 m from the vessel MAC TAC group killed 7 d after irradiation. The intestinal
wall, the 10B dose component is 3.0, 0.2, and 0.005 Gy, respec- mucosa recovered, whereas the bone marrow was severely
tively. However, the crypt microcolony assay results (Fig. 2) depleted, indicating that this mouse died from the bone marrow
indicate that this potential penetration of the particle dose syndrome despite a physical absorbed dose in the microvascu-
MEDICAL SCIENCES
outside the vessel had no detectable effect on the crypt stem cell lature that exceeded 27 Gy.
survival. The 7.5-Gy beam-only and 7.5-Gy beam plus MAC TAC
groups show considerably different survival times (Fig. 3), yet
Mouse Survival. Fig. 3A shows the survival of the beam-only the mode of death was the same in both groups, namely, bone
groups as a function of time after whole-body neutron beam marrow depletion. The very high ( 50 Gy) absorbed dose in the
irradiation. All mice (n 12) given 5.7 Gy and eight of 10 mice blood (see Table 1) in the presence of the MAC TAC liposomes
given 7.5 Gy lived beyond 30 d, indicating that these beam doses
were below the LD50 for death from the bone marrow syndrome.
At neutron beam doses of 8.3, 9.0, and 10.0 Gy, all mice (n 28
total) died within 4–9 d (Fig. 3A). Fig. 4 shows hematoxylin-
and-eosin-stained histological sections of small intestine (jeju-
num) and bone marrow from mice in the 8.3- and 9.0-Gy
beam-only groups that were killed 9 and 5 d after irradiation,
respectively. The intestinal mucosa was well on the way to
recovery in the mouse that received the 8.3-Gy beam-only dose,
whereas the intestinal epithelium was severely denuded in the
mouse that received the 9.0-Gy beam-only dose, which is indic-
ative of death from the GI syndrome. The bone marrow was
severely depleted and showed extensive necrosis of the matrix
and widespread hemorrhaging in both mice. Thus, the histopa-
thology from the neutron beam-only irradiation groups indicates
that the transition from a bone-marrow-induced death to a GI
syndrome-induced death occurs at a whole-body absorbed dose
between 8.3 and 9.0 Gy.
Fig. 3B shows the survival of the beam-plus-liposome groups Fig. 4. Histopathology in small intestine and bone marrow after whole-
as a function of time after whole-body neutron beam irradiation body, neutron-beam-only absorbed doses of 8.3 0.6 or 9.0 0.6 Gy. Also
with boronated liposomes in the blood. The estimated total shown are tissues from a mouse in the 8.3-Gy beam plus (MAC TAC) lipo-
absorbed doses in the vascular endothelial cells were 2- or 3-fold somes group in which the calculated absorbed dose to the endothelial cells
higher than the whole-body absorbed doses received by the crypt was 27.7 2.2 Gy.
Schuller et al. PNAS March 7, 2006 vol. 103 no. 10 3789
4. contributed enough dose to the bone marrow to cause a rapid rat brain study (9), at 30 d after irradiation, the loss of neural
death from the bone marrow syndrome. The exact mechanism of precursor cells and their progeny was shown to correlate with the
liposome-mediated delivery of boron into the bone marrow is absorbed dose in the brain parenchyma (the beam dose) and was
not known. not affected by the selective irradiation of the microvasculature
(9). The results in the rat brain parallel what we report here for
Discussion the acute loss of mouse intestinal crypt stem cells: The effect is
The cellular and subcellular events that eventually lead to the direct and not mediated by the vascular dose.
breakdown of tissue structure and function are initiated at The mixed high- and low-LET nature of the physical ab-
the time of irradiation. Our ability to preferentially increase sorbed doses in the microvasculature reported here compli-
the absorbed dose to the vascular endothelial cells allows cates a direct comparison to the low-LET doses used by Paris
direct testing of the role played by microvascular damage in the et al. (5). However, a biological weighting factor has been
subsequent development of normal tissue damage. We have measured for BSH in the rat spinal cord using the myeloparesis
established that whole-body neutron beam-only doses of 9.0 endpoint (21), where white matter necrosis has been shown to
Gy represent the threshold for death from the GI syndrome. be directly related to vascular damage (11, 12). BSH in the
Our approach was to use neutron beam doses below the 9.0 Gy CNS produces the same 10B distribution pattern as the lipo-
threshold for the GI syndrome in combination with boronated somes in the intestine in the current study: The 10B is restricted
liposomes in the blood. The additional short-ranged boron to the vessel lumen. The weighting factor derived in the rat
neutron capture dose in the blood selectively increased the spinal cord for BSH is 0.46 and converts the 10B physical dose
total absorbed dose in the microvasculature to values as high absorbed in the blood into a photon-equivalent dose to the
as 27.7 Gy, whereas the dose to the crypts remained 9.0 Gy. vasculature (21). Application of the BSH weighting factor to
Despite these extremely high doses to the microvasculature, the liposome 10B blood doses (Table 1) generates estimated
the crypt microcolony assay and histopathological confirma- photon equivalent doses to the intestinal vasculature of 7.0,
tion of the mode of death indicated that all observed radiation 24.2, and 26.8 Gy. In addition, the vasculature also received the
effects in the small intestine could be attributed to the nonspecific beam dose. Clearly, the upper range of the doses
whole-body neutron beam dose: the added dose to the micro- delivered to the vasculature in the beam-plus-liposome irra-
vasculature was inconsequential. We conclude that damage to diations reported here are significantly higher than the 8- to
the intestinal microvasculature is not causative in the loss of 15-Gy photon dose used in the Paris et al. (5) study.
stem cell function and the eventual depopulation of the The proof-of-principle results described here suggest that our
intestinal lining that characterizes the GI syndrome. technique for selective vascular irradiation could be useful in
The role of microvascular versus parenchymal cell damage has other non-CNS tissues, such as the lung, where the role of
long been a matter of considerable debate for late effects vascular endothelial cell apoptosis as the initiating event in the
(15–17). In recent years, it has become clear that the overall development of lethal radiation pneumonitis in the mouse is a
tissue response to radiation damage includes a complex inter- matter of debate (22, 23). This approach could also play an
action between the different cell types present that begins important role in studies of the molecular mechanisms leading
immediately after the radiation insult and persists throughout to late fibrosis in tissues, such as the lung, the GI tract, or the
the clinically silent period until the expression of the late effect kidney. Understanding the mechanisms that regulate early and
months or even years later. Radiation has been shown to result late normal tissue radiation responses may have important
in the activation of a number of early response cytokines that act implications and applications in the development of radiation
through diverse signaling pathways (18). This continuous cas- protectors or treatments for radiation exposures.
cade of cytokines has been proposed to induce a chronic
inflammatory phase, which is in turn followed by late stromal Materials and Methods
alterations, such as fibrosis (19). Radiation injury has also been Boron Analysis. The boron concentration in liquid or solid samples
likened to a ‘‘complex wound’’ in which persistent damage to the was determined by using the prompt gamma neutron activation
vascular endothelium results in eventual dysregulation of the analysis facility at the MIT reactor (24). This spectroscopic tech-
coagulation system, which in turn causes a chronic inflammatory nique measures the prompt gamma ray emitted by the recoiling 7Li
response leading to fibrotic changes (20). Because of the lack of nucleus after neutron capture in 10B using a high-purity germanium
experimental techniques for selectively irradiating potential detector. The system was calibrated by using boric acid certified by
target populations to test these hypotheses, questions still remain the National Institute of Standards and Technology and has a
as to which cell population(s) are the critical targets that initiate detection limit of 1 g for 10B. All stated uncertainties on 10B
these signaling pathways, despite the increased understanding of measurements represent one standard deviation.
the molecular responses in tissue to radiation exposure.
The present study is similar in concept to our previous work 10B-containing liposome formulations
Liposomes. Two different
that addressed the role of vascular damage in the development were used for these studies. Liposomes containing MAC embedded
of subacute and late effects in the CNS (9, 10). In those studies, in the lipid bilayer were prepared as described in ref. 25. The
the blood–brain (or spinal cord) barrier was used to keep a water-soluble TAC polyhedral borane anion derivative can be
low-molecular-weight boron compound [Na2B12H11SH (BSH)] incorporated into the interior of the liposome (26). MAC TAC
within the lumen of the blood vessels during neutron irradiation. liposomes were prepared as described in ref. 27. All boron com-
In the spinal cord study (10), an in vivo in vitro assay for O-2A pounds were enriched in the 10B isotope to 98%. The liposome
glial progenitor cells showed that after uniform irradiation with formulations had a mean vesicle diameter between 70 and 90 nm
the neutron beam alone the glial progenitor population was and contained 24 mg of total lipid per milliliter. The MAC and the
severely depleted at 1 week and remained so until the develop- MAC TAC liposome injection solutions were sterilized by passage
ment of white matter necrosis and limb paralysis at 6 months through a 0.22- m filter before use and contained 540 27 g ml
after irradiation. In contrast, the glial progenitor population and 1,580 79 g ml 10B, respectively.
remained at high levels at all times after the irradiation with the
neutron beam plus BSH in the blood. Both irradiation conditions Animals and Animal Procedures. Female BALB c mice, 8–12 weeks
were isoeffective for white matter necrosis (21). The conclusion of age, were maintained in a 12-hour light dark cycle and given
from that study was that damage to the vascular endothelium was food and water ad libitum. All procedures were reviewed and
the primary event leading to white matter necrosis (10). In the approved by the Committee on Animal Care at the Massachu-
3790 www.pnas.org cgi doi 10.1073 pnas.0600133103 Schuller et al.
5. setts Institute of Technology and were conducted according to absorbed in the blood volume within the lumen. Rydin et al.
the principles outlined in the Guide for the Care and Use of quantified this effect of vessel geometry on the dose absorbed in an
Laboratory Animals prepared by the Institute of Laboratory endothelial cell from boron neutron capture reactions restricted to
Animal Resources of the National Research Council. the lumen of a blood-filled capillary relative to the boron dose
absorbed in the blood (13). According to this model, when 10B is
Biodistribution Studies. The 10B dose distribution is directly related restricted to the lumen, the boron dose absorbed in the capillary
to the 10B concentrations in tissues at the time of irradiation. wall is one-third of the boron dose absorbed in the blood given a
Liposome biodistribution studies were carried out to determine the capillary wall thickness of 0.25 m, which is considered represen-
amount of 10B in blood, liver, skin, and small intestine as a function tative for the mice used in this study. The total physical absorbed
of time after injection. Twenty BALB c mice were injected with 0.2 dose in the vascular endothelium is the sum of the external beam
ml of the MAC liposome solution (108 g of 10B) via the retroor- dose and the vascular-specific boron dose.
bital sinus while under brief isofluorane anesthesia. Five mice were
killed by inhalation overdose of either isofluorane or carbon Crypt Regeneration Assay. The intestinal crypt microcolony assay (3)
dioxide at each of four time points (15, 30, 45, and 60 min) after was used to quantify the effects of the different absorbed dose
injection. Blood was drawn directly from the heart. The boron distributions delivered to the microvasculature and to the intestinal
concentrations in blood and samples of skin (pinna), liver, and small crypt stem cells. This assay has several advantages, such as a steep
intestine were measured by using prompt gamma neutron activation dose–response relationship and independence from the dose to
analysis. Eight mice received 0.2 ml of the MAC TAC liposome adjacent normal tissues. Based on its sensitivity, it has been used to
solution (316 g of 10B) and were killed at 30 min after injection for quantify the different biological effects of clinical fast neutron
boron analysis. therapy beams differing in radiation quality by no more than 10%
The boronated amino acid BPA was used to provide a uniform (31). In the studies reported here, mice received whole-body,
boron distribution in blood and tissues for a positive control neutron-beam irradiation either without administered boron, 30
experiment. Previous studies have shown that BPA distributes 5 min after a 0.2-ml liposome injection, or 2 h after injection of
relatively uniformly from blood into normal tissues at 2–3 h after BPA. The mice were killed 84 1 h after irradiation, and a 5-cm
injection (28). The BPA was solubilized for injection as the fructose section of the jejunum was removed, cut into 0.5-cm segments, and
complex at a concentration of 83 mg ml BPA (29). Five mice placed into 10% formalin fixative for 24–48 h. After fixation, the
received a single injection of BPA (0.2 ml; 812 g of 10B) into the intestine sections were embedded vertically in paraffin to generate
retroorbital sinus and were killed 2 h after injection for boron cross sections when cut and then stained with hematoxylin and
analysis. eosin. The numbers of regenerating crypts per circumference were
counted, with at least four sections per mouse and four mice per
Neutron Beam Irradiation. Whole-body mouse irradiations were dose point. The criteria used for scoring a regenerating crypt were
carried out in the epithermal neutron beam at the Massachusetts 10 or more contiguous epithelial cells and at least one Paneth cell
Institute of Technology Nuclear Reactor Laboratory as de- (2, 3). No correction factor was applied, because the average crypt
scribed in ref. 14. Mice were irradiated in a Lucite holder size in all irradiated groups was the same. A single, blinded observer
designed to immobilize unanesthetized mice by the four feet such
scored all slides.
that the abdomens were presented to the 16-cm-diameter hor-
izontal epithermal beam (14). Unless specifically noted, all doses
Survival Studies. Mouse survival experiments were carried out at
quoted in this paper are physical absorbed doses to which no
the following absorbed doses of a whole-body epithermal neu-
MEDICAL SCIENCES
weighting factors have been applied. Absorbed doses ranging
tron beam: 5.7 0.4, 7.5 0.5, 8.3 0.6, 9.0 0.6, and 10.0
from 3.2 0.2 to 10.0 0.7 Gy were administered with
0.7 Gy. At the three lowest doses, groups of 8–12 mice received
irradiations lasting from 6 to 20 min. The epithermal neutrons
either beam-only irradiation or irradiation together with bor-
were thermalized by 1.5 cm of Lucite, consisting of the 0.5-cm-
onated liposomes in the blood. The MAC liposomes were used
thick mouse holder and an additional 1.0-cm sheet of Lucite
for the 5.7-Gy dose level, and the MAC TAC liposomes were
placed between the holder and the beam aperture. The mouse
bodies were centered at a depth of 2.5 cm. Photon and fast used for the 7.5- and 8.3-Gy dose levels. No boronated liposomes
neutron absorbed dose rates were measured using paired ion- were administered for the 9.0- and 10.0-Gy dose levels. Mice
ization chambers with walls of graphite and tissue-equivalent were weighed daily after irradiation and killed upon entering a
A-150 plastic. The absorbed dose from neutron capture in 10B moribund state. Intestine and femur samples were harvested for
and nitrogen was determined by using the measured difference histology to ascertain the likely mode of death.
in the activation of bare and Cd-covered gold foils and kerma
coefficients of 8.66 10 8 and 7.88 10 12 Gy cm2, respec- This work was supported in part by the U.S. Department of Energy
tively. A uniform nitrogen concentration of 3.5% by weight was Nuclear Engineering and Health Physics Fellowship Program (B.W.S.)
applied for tissue and boron concentrations measured in the and by Innovations in Nuclear Infrastructure and Education Program
Contract DE-FG07-02ID14420, both of which are sponsored by the U.S.
biodistribution studies were used to determine the absorbed
Department of Energy’s Office of Nuclear Energy, Science, and Tech-
doses in the blood and vessel wall (30). nology. Additional support was provided by National Institutes of Health
Grant 1R01 CA97342-01A2 (to M.F.H.), the Westaway Family Memo-
Vascular Dose Calculations. The boron neutron capture reactions in rial Fund at Massachusetts Institute of Technology (J.A.C.), and the
the liposome groups occur, by design, only within the vessel lumen. Massachussetts Institute of Technology Center for Environmental
This creates a nonuniform dose distribution in which the dose Health Sciences through National Institute of Environmental Health
delivered to the vascular endothelium is less than the boron dose Sciences Grant ES002109.
1. Potten, C. S., Booth, C., Tudor, G. L., Booth, D., Brady, G., Hurley, P., Ashton, 5. Paris, F., Fuks, Z., Kang, A., Capodieci, P., Juan, G., Ehleiter, D., Haimovitz-
G., Clarke, R., Sakakibara, S. & Okano, H. (2003) Differentiation (Berlin) 71, Friedman, A., Cordon-Cardo, C. & Kolesnick, R. (2001) Science 293, 293–297.
28–41. 6. Ch’ang, H. J., Maj, J. G., Paris, F., Xing, H. R., Zhang, J., Truman, J. P.,
2. Potten, C. S. (2004) Radiat. Res. 161, 123–136. Cardon-Cardo, C., Haimovitz-Friedman, A., Kolesnick, R. & Fuks, Z. (2005)
3. Withers, H. R. & Elkind, M. M. (1970) Int. J. Radiat. Biol. Relat. Stud. Phys. Nat. Med. 11, 484–490.
Chem. Med. 17, 261–267. 7. Maj, J. G., Paris, F., Haimovitz-Friedman, A., Venkatraman, E., Kolesnick, R.
4. Hornsey, S. (1973) Radiat. Res. 55, 58–68. & Fuks, Z. (2003) Cancer Res. 63, 4338–4341.
Schuller et al. PNAS March 7, 2006 vol. 103 no. 10 3791
6. 8. Kolesnick, R. & Fuks, Z. (2003) Oncogene 22, 5897–5906. 20. Denham, J. W. & Hauer-Jensen, M. (2002) Radiother. Oncol. 63, 129–145.
9. Otsuka, S., Coderre, J. A., Micca, P. L., Morris, G. M., Hopewell, J. W., Rola, 21. Morris, G. M., Coderre, J. A., Hopewell, J. W., Micca, P. L., Nawrocky, M. M.,
R. & Fike, J. R. (2006) Radiat. Res. 165, in press. Liu, H. B. & Bywaters, A. (1994) Radiother. Oncol. 32, 249–255.
10. van der Kogel, A. J., Kleiboer, B. J., Verhagen, I., Morris, G. M., Hopewell, J. W. 22. Fuks, Z., Persaud, R. S., Alfieri, A., McLoughlin, M., Ehleiter, D., Schwartz,
& Coderre, J. A. (1996) in Radiation Research 1895–1995, eds. Hagen, U., Harder, J. L., Seddon, A. P., Cordon-Cardo, C. & Haimovitz-Friedman, A. (1994)
D., Jung, H. & Streffer, C. (Sturtz, Wurzburg, Germany), Vol. 2, pp. 769–772. Cancer Res. 54, 2582–2590.
11. Morris, G. M., Coderre, J. A., Bywaters, A., Whitehouse, E. & Hopewell, J. W. 23. Tee, P. G. & Travis, E. L. (1995) Cancer Res. 55, 298–302.
(1996) Radiat. Res. 146, 313–320. 24. Riley, K. & Harling, O. (1998) Nucl. Instrum. Meth. Phys. Res., Sect. B 143,
12. Morris, G. M., Coderre, J. A., Whitehouse, E. M., Micca, P. & Hopewell, J. W. 414–421.
(1994) Int. J. Radiat. Oncol. Biol. Phys. 28, 1107–1112. 25. Feakes, D. A., Shelly, K. & Hawthorne, M. F. (1995) Proc. Nat. Acad. Sci. USA
13. Rydin, R. A., Deutsch, O. L. & Murray, B. W. (1976) Phys. Med. Biol. 21,
92, 1367–1370.
134–138.
26. Feakes, D., Shelly, K., Knobler, C. & Hawthorne, M. (1994) Proc. Natl. Acad.
14. Gueulette, J., Binns, P. J., Coster, B. M., Lu, X. Q., Roberts, S. A. & Riley, K. J.
Sci. USA 91, 3029–3033.
(2005) Radiat. Res. 164, 805–809.
15. Withers, H. R., Peters, L. J. & Kogelnik, H. D. (1980) in Radiation Biology in 27. Watson-Clark, R. A., Banquerigo, M. L., Shelly, K., Hawthorne, M. F. & Brahn,
Cancer Res., eds. Meyn, R. E. & Withers, H. R. (Raven, New York), pp. 439–448. E. (1998) Proc. Natl. Acad. Sci. USA 95, 2531–2534.
16. Calvo, W., Hopewell, J. W., Reinhold, H. S. & Yeung, T. K. (1988) Br. J. Radiol. 28. Coderre, J. A. & Morris, G. M. (1999) Radiat. Res. 151, 1–18.
61, 1043–1052. 29. Coderre, J. A., Button, T. M., Micca, P. L., Fisher, C. D., Nawrocky, M. M. &
17. Hopewell, J. & Withers, H. R. (1998) Med. Phys. 25, 2265–2268. Liu, H. B. (1994) Int. J. Radiat. Oncol. Biol. Phys. 30, 643–652.
18. Rubin, P., Johnston, C. J., Williams, J. P., McDonald, S. & Finkelstein, J. N. 30. Riley, K. J., Binns, P. J. & Harling, O. K. (2003) Phys. Med. Biol. 48,
(1995) Int. J. Radiat. Oncol. Biol. Phys. 33, 99–109. 943–958.
19. Okunieff, P., Cornelison, T., Mester, M., Liu, W., Ding, I., Chen, Y., Zhang, H., 31. Gueulette, J., Octave-Prignot, M., De Costera, B. M., Wambersie, A. &
Williams, J. P. & Finkelstein, J. (2005) Int. J. Radiat. Oncol. Biol. Phys. 62, 273–278. Gregoire, V. (2004) Radiother Oncol. 73, Suppl. 2, S148–S154.
3792 www.pnas.org cgi doi 10.1073 pnas.0600133103 Schuller et al.