Thymomas are rare tumors in F344/N rats. This study summarizes 277 thymomas from NTP studies. Most thymomas were benign (84.8%) and showed heterogeneous morphology but were categorized into 6 patterns. Malignant thymomas comprised 15.2% and were diagnosed based on invasion, metastasis, or cytology. Malignant thymomas were associated with shorter survival times. While morphology varied, there was no correlation with behavior. Classification into benign vs malignant adequately describes thymomas in F344/N rats.
This document discusses research on using cancer stem cells for compound screening. It describes how cancer stem cells can be isolated from tumors and cultured. These cancer stem cells can then be used to test compounds for anti-cancer activity in vitro and validate drug candidates in vivo using xenograft models. Several examples are given of research groups that have pioneered cancer stem cell research in specific cancers like colon and lung cancer. Resources available include cancer stem cell banks, microarrays, and models that can be used to test compounds and better understand cancer stem cell biology.
This study analyzed 22 cases of primary oral melanoma through histopathological and immunohistochemical examination. The main findings were:
1) Most cases affected the hard palate and occurred in older adults, with deep levels of invasion seen in most cases.
2) Immunohistochemistry found S-100 and HMB-45 proteins were expressed in all cases, while Melan-A was negative in 3 cases.
3) Proliferation rates measured by Ki-67 were high, ranging from 15.5% to 63% of cells staining positive.
The repeated inflammation caused by monthly ovulation exposes the fallopian tube epithelium to oxidative stress, leading to transcription-associated mutations in the TP53 gene. This is believed to be the first step in the development of high grade serous ovarian carcinoma (HGSC). Estrogen and inflammatory cytokines generated during ovulation cause DNA damage in the fallopian tube cells through reactive oxygen species. Mutation of the TP53 gene prevents the cells from undergoing apoptosis in response to this damage, allowing genetic changes to accumulate and cancer to develop.
Genome Wide SNP Analysis for Inferring the Population Structure and Genetic H...Hong ChangBum
Study of genome-wide SNPs, mitochondrial DNA and Y-chromosomal DNA variation can provide a valuable information about the population structure and peopling of human populations. To explain a genetic homogeneity of Koreans and population structure of Koreans and the East Asian populations, we analyzed 153 individuals from the Korea and 77 individuals from the East Asia at 46,559 common single-nucleotide polymorphic loci. The 137 CHB and 113 JPT individuals at 25,769 common SNPs from the International HapMap project were further analyzed to reveal the population structure of the East Asians. Principal Component analyses (PCA) and population differentiation ( ) are examined. In the PCA test, the Jeju individuals were slightly different from other Koreans but their values were not significant. This reflect the genetic homogeneity of Korea population. In general, all the individual samples studied here were clustered into subset of ethnic origin according to their geographical location except Mongolians. Whole genome sequencing of Koreans and other population genome by next generation sequencing technology will provide great opportunity to understand the population expansion and peopling of Korea better.
On the cancer of wild animals somayeh zaminpira - sorush niknamianbanafsheh61
Cancer affects all animals containing eukaryotic cells. Less is known about the cancers that affect wild animals, since they move around and may not be easily observed for a long period of time. This review about cancers in wild animals may have useful data for the study of human cancers as well. Certain cancers in dinosaurs show that this metabolic disease is primitive and may have been around since the beginning of the multicellular organisms.
Stem cells can divide into specialized cell types or more stem cells. They are found in organs like the liver, lungs and colon as well as the brain where they are called glia. Gliomas are brain or spine tumors that resemble glia cells. Glioblastoma multiform is the most common and dangerous glioma tumor. Researchers presented findings showing that adding miRNA to glioma tumor cells can make them vulnerable to chemotherapy, which previously had little effect. These results could help develop treatments to cure glioma tumors and provide insights for cancer and neurological research.
This document is a curriculum vitae for Kazuyoshi Kohu that provides biographical and career information in 3 sections - Personal Information, Education History, and Professional Experience. It lists his name, date and place of birth, contact information, education credentials including undergraduate and graduate degrees from Hiroshima University and Osaka University, as well as his current position as Senior Research Scientist at the Cancer Science Institute of Singapore and past research roles.
Ong et al_The M694V mutation in Armenian-Americans_a 10-year retrospective st...Frank Ong, MD, CPI
This study retrospectively analyzed MEFV gene mutation testing results from 476 patients seen at UCLA between 2002-2012 to correlate genotypes with clinical phenotypes in different populations. They found:
1. The M694V mutation was significantly associated with Armenian ethnicity, seen in 35.3% of Armenian patients as a homozygous mutation and 77.3% of Armenian compound heterozygotes, compared to only 2.9% and 47.1% in non-Armenians respectively.
2. Armenian patients had a significant trend of increasing genetic contribution of the M694V mutation, while non-Armenians showed a decreasing trend.
3. The M694V mutation was also more prevalent in single mutation Armenian patients
This document discusses research on using cancer stem cells for compound screening. It describes how cancer stem cells can be isolated from tumors and cultured. These cancer stem cells can then be used to test compounds for anti-cancer activity in vitro and validate drug candidates in vivo using xenograft models. Several examples are given of research groups that have pioneered cancer stem cell research in specific cancers like colon and lung cancer. Resources available include cancer stem cell banks, microarrays, and models that can be used to test compounds and better understand cancer stem cell biology.
This study analyzed 22 cases of primary oral melanoma through histopathological and immunohistochemical examination. The main findings were:
1) Most cases affected the hard palate and occurred in older adults, with deep levels of invasion seen in most cases.
2) Immunohistochemistry found S-100 and HMB-45 proteins were expressed in all cases, while Melan-A was negative in 3 cases.
3) Proliferation rates measured by Ki-67 were high, ranging from 15.5% to 63% of cells staining positive.
The repeated inflammation caused by monthly ovulation exposes the fallopian tube epithelium to oxidative stress, leading to transcription-associated mutations in the TP53 gene. This is believed to be the first step in the development of high grade serous ovarian carcinoma (HGSC). Estrogen and inflammatory cytokines generated during ovulation cause DNA damage in the fallopian tube cells through reactive oxygen species. Mutation of the TP53 gene prevents the cells from undergoing apoptosis in response to this damage, allowing genetic changes to accumulate and cancer to develop.
Genome Wide SNP Analysis for Inferring the Population Structure and Genetic H...Hong ChangBum
Study of genome-wide SNPs, mitochondrial DNA and Y-chromosomal DNA variation can provide a valuable information about the population structure and peopling of human populations. To explain a genetic homogeneity of Koreans and population structure of Koreans and the East Asian populations, we analyzed 153 individuals from the Korea and 77 individuals from the East Asia at 46,559 common single-nucleotide polymorphic loci. The 137 CHB and 113 JPT individuals at 25,769 common SNPs from the International HapMap project were further analyzed to reveal the population structure of the East Asians. Principal Component analyses (PCA) and population differentiation ( ) are examined. In the PCA test, the Jeju individuals were slightly different from other Koreans but their values were not significant. This reflect the genetic homogeneity of Korea population. In general, all the individual samples studied here were clustered into subset of ethnic origin according to their geographical location except Mongolians. Whole genome sequencing of Koreans and other population genome by next generation sequencing technology will provide great opportunity to understand the population expansion and peopling of Korea better.
On the cancer of wild animals somayeh zaminpira - sorush niknamianbanafsheh61
Cancer affects all animals containing eukaryotic cells. Less is known about the cancers that affect wild animals, since they move around and may not be easily observed for a long period of time. This review about cancers in wild animals may have useful data for the study of human cancers as well. Certain cancers in dinosaurs show that this metabolic disease is primitive and may have been around since the beginning of the multicellular organisms.
Stem cells can divide into specialized cell types or more stem cells. They are found in organs like the liver, lungs and colon as well as the brain where they are called glia. Gliomas are brain or spine tumors that resemble glia cells. Glioblastoma multiform is the most common and dangerous glioma tumor. Researchers presented findings showing that adding miRNA to glioma tumor cells can make them vulnerable to chemotherapy, which previously had little effect. These results could help develop treatments to cure glioma tumors and provide insights for cancer and neurological research.
This document is a curriculum vitae for Kazuyoshi Kohu that provides biographical and career information in 3 sections - Personal Information, Education History, and Professional Experience. It lists his name, date and place of birth, contact information, education credentials including undergraduate and graduate degrees from Hiroshima University and Osaka University, as well as his current position as Senior Research Scientist at the Cancer Science Institute of Singapore and past research roles.
Ong et al_The M694V mutation in Armenian-Americans_a 10-year retrospective st...Frank Ong, MD, CPI
This study retrospectively analyzed MEFV gene mutation testing results from 476 patients seen at UCLA between 2002-2012 to correlate genotypes with clinical phenotypes in different populations. They found:
1. The M694V mutation was significantly associated with Armenian ethnicity, seen in 35.3% of Armenian patients as a homozygous mutation and 77.3% of Armenian compound heterozygotes, compared to only 2.9% and 47.1% in non-Armenians respectively.
2. Armenian patients had a significant trend of increasing genetic contribution of the M694V mutation, while non-Armenians showed a decreasing trend.
3. The M694V mutation was also more prevalent in single mutation Armenian patients
Cytogenetic and Molecular Characterization of Hematological Neoplasm in an Ec...Andresz26
This study characterized the cytogenetic and molecular features of hematological malignancies in an Ecuadorian population. The researchers analyzed over 4,000 patients between 1984-2012, detecting chromosome abnormalities in around 46% via conventional cytogenetics. Specific genetic fusions were also identified, including BCR-ABL (present in 95% of CML patients as the b2/a2 transcript), PML-RARA (showing the bcr2 and bcr3 transcripts but not bcr1), CBFB-MYH11 (all cases exhibited the F transcript), and MLL-AF4 (all cases displayed the e7-e8 transcript). The frequencies of some fusion gene subtypes differed from
This document summarizes a presentation given by Professor Ian Day about the potential for genetics to enable personalized healthcare. It discusses what is contained in the human genome, including genes, proteins, and variations. It provides examples of how genetic testing can help with diagnosis, disease risk prediction, and drug dosing. While full genome sequencing is currently expensive, the goal is to reduce the cost to $1,000 or less in the next 5 years. Understanding the genome could help tailor medical care to an individual's genetic profile.
This document discusses the FOXP3 gene as a promising candidate gene in susceptibility to generalized vitiligo. It summarizes that FOXP3 is the master transcription factor that regulates regulatory T cells, which play an important role in preventing autoimmunity. Studies have found associations between polymorphisms in the FOXP3 gene and an increased risk of vitiligo. The document argues that further investigation of FOXP3 genetic variants and their effects on regulatory T cell development and function could provide insights into vitiligo pathogenesis and potential new therapeutic approaches targeting the FOXP3 gene/regulatory T cell network.
This document provides summaries of 16 research articles related to Niemann-Pick disease type C1 (NPC1). The articles investigate potential biomarkers for early diagnosis of NPC1, examine the urinary excretion and metabolism of drugs used to treat NPC1, identify new potential biomarkers through metabolic profiling, and study the effects of glycosphingolipid storage and treatment on various cells and pathways involved in NPC1 pathogenesis.
This document provides summaries of 16 research articles related to Niemann-Pick disease type C1 (NPC1). The articles investigate potential biomarkers for early diagnosis of NPC1, examine the urinary excretion and metabolism of drugs used to treat NPC1, identify new potential biomarkers through metabolic profiling, and study the effects of glycosphingolipid storage and treatment on various cells and pathways involved in NPC1 pathogenesis.
Alternative lengthening of telomeres is enriched in, and impacts survival of ...Joshua Mangerel
This study investigated the prevalence and significance of alternative lengthening of telomeres (ALT) in pediatric brain tumors. The researchers screened 517 pediatric brain tumor samples for ALT using the C-circle assay and validated the results with other assays. They found that ALT was detected in a subset of malignant pediatric brain tumors, especially primitive neuroectodermal tumors, choroid plexus carcinomas, and high-grade gliomas. Somatic mutations in TP53 were strongly associated with ALT. ALT attenuated the poor prognosis associated with TP53 mutations in some tumor types. ALT positive tumors had higher survival rates than ALT negative tumors for children with TP53 mutant malignant gliomas and choroid plexus carcinomas. This suggests ALT may impact survival
Antonio Ahn is a medical researcher from New Zealand. He received his PhD in pathology from the University of Otago, where he currently works as a lab demonstrator. His research focuses on bioinformatics analysis of RNA-seq and methylation data to study protein-coding genes, lncRNAs, transposable elements, and immune cell infiltration in cancer. He has published several papers on epigenetic changes and drug resistance in melanoma.
Whats Beyond The Finished Human Genome SequenceJohn Morgan
The document summarizes the progress and findings of the Human Genome Project from its inception in 1990 through its completion in 2003. It discusses how the project established the foundations for genetic mapping and sequencing chromosomes. After the working draft was announced in 2000 and the project was completed in 2003, subsequent research focused on fully sequencing and analyzing the remaining chromosomes. This led to insights into genetic diseases and variation in gene and chromatin distribution across chromosomes. The document also discusses subsequent projects like ENCODE and HapMap that built upon the human genome sequence to map functional elements and genetic variations respectively.
This document lists publications and announcements by G. Trimis, including:
1. Six peer-reviewed journal publications from 2005-2012 on topics relating to p53, p21, tumor-stroma interactions, and oral cancers.
2. Five conference announcements and presentations from 2005-2010 on non-autonomous p53/p21 signaling in tumor stroma, expression of tumor suppressors in oral lesions, and phospho-4E-BP1 expression in oral lichen planus.
3. G. Trimis is affiliated with the Laboratory of Biological Chemistry and Department of Basic Sciences at the Medical School of University of Athens.
Metastasis is defined as the spread of cancer from the primary site to a secondary site. Metastasis accounts for 90% of cancer deaths and involves invasion, angiogenesis, and the spread of cancer cells through the lymphatic system or bloodstream to seed new tumors in distant organs. The process is influenced by the tumor microenvironment, epithelial-to-mesenchymal transition, cancer cell metabolism and physical properties, circulating tumor cells, the seed and soil hypothesis of organotropism, and immune system interactions. Understanding the chronology and biology of metastasis is crucial for improving cancer outcomes.
Continuous Exposure to Chrysotile Asbestos Can CauseGhazal Khan
This document summarizes a study that found continuous exposure to chrysotile asbestos can induce transformation of human mesothelial cells through signaling of HMGB1 and TNF-α, similar to effects of crocidolite asbestos exposure. Both asbestos types induced epithelial-to-mesenchymal transition in cells, characterized by downregulation of E-cadherin and phosphorylation/nuclear translocation of β-catenin. While crocidolite exposure induced sustained gene expression changes and HMGB1 release, chrysotile effects returned to baseline within 5-8 weeks. Continuous chrysotile exposure was required to maintain elevated HMGB1 levels, supporting the role of fiber persistence in biological activity.
Cancer stem cells &new therapeutics methodsmahdi hatami
This document discusses cancer stem cells (CSCs) and new therapeutic approaches to target them. It introduces CSCs, their characteristics like self-renewal and chemoresistance. CSCs can be identified by specific cell surface markers and sphere formation assays. New therapies aim to target CSCs' signaling pathways, surface markers, drug efflux pumps, and microenvironment. Targeting CSCs provides a promising approach for improving cancer treatment outcomes as CSCs are responsible for tumor growth, metastasis, and therapeutic resistance.
This document traces the history of research on teratomas and embryonic carcinoma (EC) cells from ancient times to present day, including several key discoveries and advances:
1) Rudolph Virchow coined the term "teratoma" in the 19th century to describe tumors containing tissues from all three germ layers.
2) In the 1950s-60s, mouse EC cells were discovered and shown to be pluripotent cancer stem cells capable of generating complex teratomas, resembling the early embryo.
3) The first human EC cell lines were established in the 1970s, though they differed from mouse EC cells. Surface antigens helped characterize both mouse and human EC cells and embryonic stem cells
A normal cell can be transformed into a cancerous cell. Discuss the therapeutic strategies that are employed to target the cellular transformation process for cancer prevention and treatment.
This curriculum vitae summarizes the qualifications and experience of Ximiao He. He received his Ph.D. in Genomics from the Beijing Institute of Genomics in China, where he conducted research on genome databases and the analysis of human CpG islands and DNA methylation in cancer. He is currently a postdoctoral research fellow at the National Cancer Institute studying the effects of nucleosome occupancy and methylation on gene regulation. His research interests include DNA methylation, alternative splicing, and computational genomics tools. He has over 20 publications in peer-reviewed journals and has presented his research at several conferences.
This review article discusses emerging understanding of tumor heterogeneity at multiple scales. Cancer is characterized by heterogeneous genetic alterations and cellular metabolism at the organ, tissue, and cellular level. Key features of cancer heterogeneity are summarized by the 10 hallmarks of cancer. At the DNA and cellular level, germline and somatic mutations cause abnormal cell behavior and growth. The tumor microenvironment and its components also facilitate or restrict tumor growth. Research is gaining a tremendous surge of comprehension of these disease mechanisms, which will lead to novel drug targets and challenges in drug discovery. Integrated multi-omic technologies are essential tools to understand all the various cellular changes involved in tumorigenesis. The review examines features of cancer heterogeneity and discusses how multiplexed technologies can facilitate
The document reports that the tumor suppressor HACE1, an E3 ubiquitin ligase, interacts with and ubiquitylates the autophagy receptor Optineurin (OPTN) both in vitro and in vivo. HACE1 conjugates Lys48-linked polyubiquitin chains onto OPTN, which targets OPTN for autophagic degradation rather than proteasomal degradation. Knocking down HACE1 inhibits ubiquitylation of OPTN. The HACE1-OPTN interaction was found to activate selective autophagy and synergistically suppress growth and tumorigenicity of lung cancer cells. This suggests an underappreciated role for ubiquitin signaling in regulating autophag
This document discusses vitamin D and its potential relationship to ovarian cancer risk. It notes that vitamin D receptor (VDR) expression is higher in ovarian cancer cells than normal ovarian cells. Studies have found that vitamin D administration can inhibit growth and induce apoptosis in ovarian cancer cell lines. The document reviews several studies that found associations between the VDR Fok1 polymorphism and increased ovarian cancer risk. In particular, there is evidence that women with the CT and TT genotypes may have higher risk. Based on these findings, the document calls for larger studies to further evaluate the relationship between the VDR Fok1 polymorphism and epithelial ovarian cancer risk, as well as measuring serum vitamin D levels in ovarian cancer patients.
Cytogenetic and Molecular Characterization of Hematological Neoplasm in an Ec...Andresz26
This study characterized the cytogenetic and molecular features of hematological malignancies in an Ecuadorian population. The researchers analyzed over 4,000 patients between 1984-2012, detecting chromosome abnormalities in around 46% via conventional cytogenetics. Specific genetic fusions were also identified, including BCR-ABL (present in 95% of CML patients as the b2/a2 transcript), PML-RARA (showing the bcr2 and bcr3 transcripts but not bcr1), CBFB-MYH11 (all cases exhibited the F transcript), and MLL-AF4 (all cases displayed the e7-e8 transcript). The frequencies of some fusion gene subtypes differed from
This document summarizes a presentation given by Professor Ian Day about the potential for genetics to enable personalized healthcare. It discusses what is contained in the human genome, including genes, proteins, and variations. It provides examples of how genetic testing can help with diagnosis, disease risk prediction, and drug dosing. While full genome sequencing is currently expensive, the goal is to reduce the cost to $1,000 or less in the next 5 years. Understanding the genome could help tailor medical care to an individual's genetic profile.
This document discusses the FOXP3 gene as a promising candidate gene in susceptibility to generalized vitiligo. It summarizes that FOXP3 is the master transcription factor that regulates regulatory T cells, which play an important role in preventing autoimmunity. Studies have found associations between polymorphisms in the FOXP3 gene and an increased risk of vitiligo. The document argues that further investigation of FOXP3 genetic variants and their effects on regulatory T cell development and function could provide insights into vitiligo pathogenesis and potential new therapeutic approaches targeting the FOXP3 gene/regulatory T cell network.
This document provides summaries of 16 research articles related to Niemann-Pick disease type C1 (NPC1). The articles investigate potential biomarkers for early diagnosis of NPC1, examine the urinary excretion and metabolism of drugs used to treat NPC1, identify new potential biomarkers through metabolic profiling, and study the effects of glycosphingolipid storage and treatment on various cells and pathways involved in NPC1 pathogenesis.
This document provides summaries of 16 research articles related to Niemann-Pick disease type C1 (NPC1). The articles investigate potential biomarkers for early diagnosis of NPC1, examine the urinary excretion and metabolism of drugs used to treat NPC1, identify new potential biomarkers through metabolic profiling, and study the effects of glycosphingolipid storage and treatment on various cells and pathways involved in NPC1 pathogenesis.
Alternative lengthening of telomeres is enriched in, and impacts survival of ...Joshua Mangerel
This study investigated the prevalence and significance of alternative lengthening of telomeres (ALT) in pediatric brain tumors. The researchers screened 517 pediatric brain tumor samples for ALT using the C-circle assay and validated the results with other assays. They found that ALT was detected in a subset of malignant pediatric brain tumors, especially primitive neuroectodermal tumors, choroid plexus carcinomas, and high-grade gliomas. Somatic mutations in TP53 were strongly associated with ALT. ALT attenuated the poor prognosis associated with TP53 mutations in some tumor types. ALT positive tumors had higher survival rates than ALT negative tumors for children with TP53 mutant malignant gliomas and choroid plexus carcinomas. This suggests ALT may impact survival
Antonio Ahn is a medical researcher from New Zealand. He received his PhD in pathology from the University of Otago, where he currently works as a lab demonstrator. His research focuses on bioinformatics analysis of RNA-seq and methylation data to study protein-coding genes, lncRNAs, transposable elements, and immune cell infiltration in cancer. He has published several papers on epigenetic changes and drug resistance in melanoma.
Whats Beyond The Finished Human Genome SequenceJohn Morgan
The document summarizes the progress and findings of the Human Genome Project from its inception in 1990 through its completion in 2003. It discusses how the project established the foundations for genetic mapping and sequencing chromosomes. After the working draft was announced in 2000 and the project was completed in 2003, subsequent research focused on fully sequencing and analyzing the remaining chromosomes. This led to insights into genetic diseases and variation in gene and chromatin distribution across chromosomes. The document also discusses subsequent projects like ENCODE and HapMap that built upon the human genome sequence to map functional elements and genetic variations respectively.
This document lists publications and announcements by G. Trimis, including:
1. Six peer-reviewed journal publications from 2005-2012 on topics relating to p53, p21, tumor-stroma interactions, and oral cancers.
2. Five conference announcements and presentations from 2005-2010 on non-autonomous p53/p21 signaling in tumor stroma, expression of tumor suppressors in oral lesions, and phospho-4E-BP1 expression in oral lichen planus.
3. G. Trimis is affiliated with the Laboratory of Biological Chemistry and Department of Basic Sciences at the Medical School of University of Athens.
Metastasis is defined as the spread of cancer from the primary site to a secondary site. Metastasis accounts for 90% of cancer deaths and involves invasion, angiogenesis, and the spread of cancer cells through the lymphatic system or bloodstream to seed new tumors in distant organs. The process is influenced by the tumor microenvironment, epithelial-to-mesenchymal transition, cancer cell metabolism and physical properties, circulating tumor cells, the seed and soil hypothesis of organotropism, and immune system interactions. Understanding the chronology and biology of metastasis is crucial for improving cancer outcomes.
Continuous Exposure to Chrysotile Asbestos Can CauseGhazal Khan
This document summarizes a study that found continuous exposure to chrysotile asbestos can induce transformation of human mesothelial cells through signaling of HMGB1 and TNF-α, similar to effects of crocidolite asbestos exposure. Both asbestos types induced epithelial-to-mesenchymal transition in cells, characterized by downregulation of E-cadherin and phosphorylation/nuclear translocation of β-catenin. While crocidolite exposure induced sustained gene expression changes and HMGB1 release, chrysotile effects returned to baseline within 5-8 weeks. Continuous chrysotile exposure was required to maintain elevated HMGB1 levels, supporting the role of fiber persistence in biological activity.
Cancer stem cells &new therapeutics methodsmahdi hatami
This document discusses cancer stem cells (CSCs) and new therapeutic approaches to target them. It introduces CSCs, their characteristics like self-renewal and chemoresistance. CSCs can be identified by specific cell surface markers and sphere formation assays. New therapies aim to target CSCs' signaling pathways, surface markers, drug efflux pumps, and microenvironment. Targeting CSCs provides a promising approach for improving cancer treatment outcomes as CSCs are responsible for tumor growth, metastasis, and therapeutic resistance.
This document traces the history of research on teratomas and embryonic carcinoma (EC) cells from ancient times to present day, including several key discoveries and advances:
1) Rudolph Virchow coined the term "teratoma" in the 19th century to describe tumors containing tissues from all three germ layers.
2) In the 1950s-60s, mouse EC cells were discovered and shown to be pluripotent cancer stem cells capable of generating complex teratomas, resembling the early embryo.
3) The first human EC cell lines were established in the 1970s, though they differed from mouse EC cells. Surface antigens helped characterize both mouse and human EC cells and embryonic stem cells
A normal cell can be transformed into a cancerous cell. Discuss the therapeutic strategies that are employed to target the cellular transformation process for cancer prevention and treatment.
This curriculum vitae summarizes the qualifications and experience of Ximiao He. He received his Ph.D. in Genomics from the Beijing Institute of Genomics in China, where he conducted research on genome databases and the analysis of human CpG islands and DNA methylation in cancer. He is currently a postdoctoral research fellow at the National Cancer Institute studying the effects of nucleosome occupancy and methylation on gene regulation. His research interests include DNA methylation, alternative splicing, and computational genomics tools. He has over 20 publications in peer-reviewed journals and has presented his research at several conferences.
This review article discusses emerging understanding of tumor heterogeneity at multiple scales. Cancer is characterized by heterogeneous genetic alterations and cellular metabolism at the organ, tissue, and cellular level. Key features of cancer heterogeneity are summarized by the 10 hallmarks of cancer. At the DNA and cellular level, germline and somatic mutations cause abnormal cell behavior and growth. The tumor microenvironment and its components also facilitate or restrict tumor growth. Research is gaining a tremendous surge of comprehension of these disease mechanisms, which will lead to novel drug targets and challenges in drug discovery. Integrated multi-omic technologies are essential tools to understand all the various cellular changes involved in tumorigenesis. The review examines features of cancer heterogeneity and discusses how multiplexed technologies can facilitate
The document reports that the tumor suppressor HACE1, an E3 ubiquitin ligase, interacts with and ubiquitylates the autophagy receptor Optineurin (OPTN) both in vitro and in vivo. HACE1 conjugates Lys48-linked polyubiquitin chains onto OPTN, which targets OPTN for autophagic degradation rather than proteasomal degradation. Knocking down HACE1 inhibits ubiquitylation of OPTN. The HACE1-OPTN interaction was found to activate selective autophagy and synergistically suppress growth and tumorigenicity of lung cancer cells. This suggests an underappreciated role for ubiquitin signaling in regulating autophag
This document discusses vitamin D and its potential relationship to ovarian cancer risk. It notes that vitamin D receptor (VDR) expression is higher in ovarian cancer cells than normal ovarian cells. Studies have found that vitamin D administration can inhibit growth and induce apoptosis in ovarian cancer cell lines. The document reviews several studies that found associations between the VDR Fok1 polymorphism and increased ovarian cancer risk. In particular, there is evidence that women with the CT and TT genotypes may have higher risk. Based on these findings, the document calls for larger studies to further evaluate the relationship between the VDR Fok1 polymorphism and epithelial ovarian cancer risk, as well as measuring serum vitamin D levels in ovarian cancer patients.
Lecture 2 european conquest of africa - online shorterLACCD
Europeans colonized Africa in the late 19th century for economic and geopolitical reasons. New technologies like steamships and quinine increased Europe's ability to explore and conquer Africa. At the Berlin Conference of 1884-85, European powers divided up much of Africa without African input. Nations like Britain, France, Germany, Portugal and Belgium established colonies across Africa to gain control of resources and trade routes. King Leopold II of Belgium personally controlled the Congo Free State for rubber and used brutal forced labor that killed millions. European colonization of Africa was driven by competition for land and wealth between rising imperial powers in the late 19th century.
Este documento presenta un análisis de la canción "Cenizas" de la cantante española Malú. Incluye información biográfica sobre Malú, detalles sobre el álbum y género musical de la canción, la letra completa con sus diferentes partes, y la opinión personal de la autora sobre la canción y el proceso de realizar el análisis.
es un trabajo en donde se pone en practica lo aprendido durante el semestre, aquí tomamos en cuenta los requerimientos de la organización de una red LAN. Al igual otros aspectos referentes a la materia.
actualización de los recursos de la red de acuerdo a los requerimientos de la...armandobr
Este documento describe las prácticas de simulación realizadas en el software Packet Tracert para actualizar los recursos de una red LAN. Explica que primero se debe entender los requerimientos y condiciones de la organización para determinar las actualizaciones necesarias. Luego, destaca la importancia de simular las actualizaciones propuestas en Packet Tracert antes de implementarlas en la red real para evitar errores. Finalmente, detalla algunas prácticas de simulación específicas realizadas en Packet Tracert, como la configuración de un DMZ y firewall
Este documento discute el tratamiento periodontal en pacientes ancianos. Señala que la edad no es una contraindicación para la cirugía periodontal, pero el tratamiento quirúrgico requiere consideraciones especiales para pacientes ancianos. También destaca que el pronóstico de la enfermedad periodontal suele ser peor en ancianos, y que el tratamiento debe adaptarse a cada paciente considerando factores como su salud general y capacidad de higiene oral.
Histopathological Patterns of Germ Cell Tumours of Ovary in a Tertiary Level ...inventionjournals
This document summarizes research on histopathological patterns of germ cell tumors of the ovary. The study found that benign cystic teratomas (dermoid cysts) made up the highest percentage at 26.47%, followed by dysgerminoma at 1.96%, immature teratoma at 0.98%, and yolk sac tumor at 0.98%. Germ cell tumors are more common in younger patients and can be benign or malignant. The histopathological patterns and characteristics of various germ cell tumors are described, including dysgerminoma, yolk sac tumor, embryonal carcinoma, polyembryoma, choriocarcinoma, and teratomas. Tumor markers such
This study analyzed DNA sequences from nine genes (three plastid, three mitochondrial, and three nuclear) from 100 plant species to better understand relationships among basal angiosperms. Phylogenetic analyses strongly supported Amborella, Nymphaeaceae, and Austrobaileyales as the earliest diverging lineages of flowering plants. The analyses also supported magnoliids as a monophyletic group consisting of Magnoliales, Laurales, Piperales, and Canellales. However, relationships among Ceratophyllum, Chloranthaceae, magnoliids, monocots, and eudicots were mostly unresolved with low support. Examination of substitution patterns supported placement of Amborella and others
Cytogenetic an Experimental Monitoring Test for Plant ExtractsIOSRJPBS
More than two centuries have been passed since the chromosomes have been firstly observed in plant cells by Nageli in 1842. During this long period, chromosomes have been discovered in human cells and well recognized as a source of genes locations. The effects of chemicals and environmental pollution in human health and caners became an interested field of studying diver mutagens and their role in affecting the genetic materials. Cytogenetic tests were the main tools to evaluate the effects of those mutagens on human genome and chromosomes. Many techniques have been used for these purposes including in vitro and in vivo analyzing tests using human and animal cells. The intent of this article is to review the role of cytogenetic techniques in detecting the effects of mutagens on chromosomal aberrations and the role of plant extracts in monitoring these effects
Il ruolo degli ultrasuoni, parametri clinici e scintigrafia, per prevedere la...MerqurioEditore_redazione
This study evaluated clinical, laboratory, ultrasound, and scintigraphy parameters in 143 patients with thyroid nodules to determine factors predictive of malignancy. 65% of nodules were benign and 35% were malignant. There were no significant differences in gender, thyroid hormone levels, autoantibodies, or scintigraphy results between benign and malignant nodules. However, ultrasound found higher rates of microcalcifications, irregular borders, hypoechogenicity, and central flow in malignant nodules. A prediction model identified age over 39, irregular borders, microcalcifications, and nodule size over 2cm as predictive of malignancy, with 81.7% accuracy. This study confirms increased malignancy risk in patients over 39
1- Why was the Tomasetti et al article so misinterpreted by thAgripinaBeaulieuyw
1- Why was the Tomasetti et al article so misinterpreted by the media? Draw from
your own personal experiences to discuss other scientific phenomenon that has
been similarly misinterpreted.
2- What might be the consequences of scientific misreporting of this article?
3- What is the overall value of the Tomasetti et al paper? Cite two and be specific in
your rational for selecting these reasons.
4- Cite three criticisms of this paper. Be specific in the rationale for your criticism.
5- Design an experiment which might distinguish between environmental effects
and replicative errors in canter etiology.
You may assume you have access to all resources currently available to scientists
today,
Be specific in elucidating the application of the scientific method to your
experiment:
1) Observation
2) Hypothesis
3) Predictions
4) Experiment: Independent and dependent variables, controls, uncontrolled
variables, sample size
5) Results (predicted): How would you analyze your data
6)Conclusions: predict conclusions for the various outcomes of your experiment
REPORT
◥
CANCER ETIOLOGY
Stem cell divisions, somatic
mutations, cancer etiology, and
cancer prevention
Cristian Tomasetti,1,2* Lu Li,2 Bert Vogelstein3*
Cancers are caused by mutations that may be inherited, induced by environmental
factors, or result from DNA replication errors (R). We studied the relationship between
the number of normal stem cell divisions and the risk of 17 cancer types in 69 countries
throughout the world. The data revealed a strong correlation (median = 0.80) between
cancer incidence and normal stem cell divisions in all countries, regardless of their
environment. The major role of R mutations in cancer etiology was supported by an
independent approach, based solely on cancer genome sequencing and epidemiological
data, which suggested that R mutations are responsible for two-thirds of the mutations
in human cancers. All of these results are consistent with epidemiological estimates of the
fraction of cancers that can be prevented by changes in the environment. Moreover, they
accentuate the importance of early detection and intervention to reduce deaths from the
many cancers arising from unavoidable R mutations.
I
t is now widely accepted that cancer is the
result of the gradual accumulation of driver
gene mutations that successively increase cell
proliferation (1–3). But what causes these muta-
tions? The role of environmental factors (E)
in cancer development has long been evident
from epidemiological studies, and this has fun-
damental implications for primary prevention.
The role of heredity (H) has been conclusively
demonstrated from both twin studies (4) and the
identification of the genes responsible for cancer
predisposition syndromes (3, 5). We recently hy-
pothesized that a third source—mutations due to
the random mistakes made during normal DNA
replication (R)—can explain why cancers occur
much more commonly in som ...
1- Why was the Tomasetti et al article so misinterpreted by thsachazerbelq9l
1- Why was the Tomasetti et al article so misinterpreted by the media? Draw from
your own personal experiences to discuss other scientific phenomenon that has
been similarly misinterpreted.
2- What might be the consequences of scientific misreporting of this article?
3- What is the overall value of the Tomasetti et al paper? Cite two and be specific in
your rational for selecting these reasons.
4- Cite three criticisms of this paper. Be specific in the rationale for your criticism.
5- Design an experiment which might distinguish between environmental effects
and replicative errors in canter etiology.
You may assume you have access to all resources currently available to scientists
today,
Be specific in elucidating the application of the scientific method to your
experiment:
1) Observation
2) Hypothesis
3) Predictions
4) Experiment: Independent and dependent variables, controls, uncontrolled
variables, sample size
5) Results (predicted): How would you analyze your data
6)Conclusions: predict conclusions for the various outcomes of your experiment
REPORT
◥
CANCER ETIOLOGY
Stem cell divisions, somatic
mutations, cancer etiology, and
cancer prevention
Cristian Tomasetti,1,2* Lu Li,2 Bert Vogelstein3*
Cancers are caused by mutations that may be inherited, induced by environmental
factors, or result from DNA replication errors (R). We studied the relationship between
the number of normal stem cell divisions and the risk of 17 cancer types in 69 countries
throughout the world. The data revealed a strong correlation (median = 0.80) between
cancer incidence and normal stem cell divisions in all countries, regardless of their
environment. The major role of R mutations in cancer etiology was supported by an
independent approach, based solely on cancer genome sequencing and epidemiological
data, which suggested that R mutations are responsible for two-thirds of the mutations
in human cancers. All of these results are consistent with epidemiological estimates of the
fraction of cancers that can be prevented by changes in the environment. Moreover, they
accentuate the importance of early detection and intervention to reduce deaths from the
many cancers arising from unavoidable R mutations.
I
t is now widely accepted that cancer is the
result of the gradual accumulation of driver
gene mutations that successively increase cell
proliferation (1–3). But what causes these muta-
tions? The role of environmental factors (E)
in cancer development has long been evident
from epidemiological studies, and this has fun-
damental implications for primary prevention.
The role of heredity (H) has been conclusively
demonstrated from both twin studies (4) and the
identification of the genes responsible for cancer
predisposition syndromes (3, 5). We recently hy-
pothesized that a third source—mutations due to
the random mistakes made during normal DNA
replication (R)—can explain why cancers occur
much more commonly in som ...
1- Why was the Tomasetti et al article so misinterpreted by th.docxjeremylockett77
1- Why was the Tomasetti et al article so misinterpreted by the media? Draw from
your own personal experiences to discuss other scientific phenomenon that has
been similarly misinterpreted.
2- What might be the consequences of scientific misreporting of this article?
3- What is the overall value of the Tomasetti et al paper? Cite two and be specific in
your rational for selecting these reasons.
4- Cite three criticisms of this paper. Be specific in the rationale for your criticism.
5- Design an experiment which might distinguish between environmental effects
and replicative errors in canter etiology.
You may assume you have access to all resources currently available to scientists
today,
Be specific in elucidating the application of the scientific method to your
experiment:
1) Observation
2) Hypothesis
3) Predictions
4) Experiment: Independent and dependent variables, controls, uncontrolled
variables, sample size
5) Results (predicted): How would you analyze your data
6)Conclusions: predict conclusions for the various outcomes of your experiment
REPORT
◥
CANCER ETIOLOGY
Stem cell divisions, somatic
mutations, cancer etiology, and
cancer prevention
Cristian Tomasetti,1,2* Lu Li,2 Bert Vogelstein3*
Cancers are caused by mutations that may be inherited, induced by environmental
factors, or result from DNA replication errors (R). We studied the relationship between
the number of normal stem cell divisions and the risk of 17 cancer types in 69 countries
throughout the world. The data revealed a strong correlation (median = 0.80) between
cancer incidence and normal stem cell divisions in all countries, regardless of their
environment. The major role of R mutations in cancer etiology was supported by an
independent approach, based solely on cancer genome sequencing and epidemiological
data, which suggested that R mutations are responsible for two-thirds of the mutations
in human cancers. All of these results are consistent with epidemiological estimates of the
fraction of cancers that can be prevented by changes in the environment. Moreover, they
accentuate the importance of early detection and intervention to reduce deaths from the
many cancers arising from unavoidable R mutations.
I
t is now widely accepted that cancer is the
result of the gradual accumulation of driver
gene mutations that successively increase cell
proliferation (1–3). But what causes these muta-
tions? The role of environmental factors (E)
in cancer development has long been evident
from epidemiological studies, and this has fun-
damental implications for primary prevention.
The role of heredity (H) has been conclusively
demonstrated from both twin studies (4) and the
identification of the genes responsible for cancer
predisposition syndromes (3, 5). We recently hy-
pothesized that a third source—mutations due to
the random mistakes made during normal DNA
replication (R)—can explain why cancers occur
much more commonly in som ...
This study analyzed canine haemangioma and haemangiosarcoma samples immunohistochemically to better characterize the biology and identify potential therapeutic targets. It found greater expression of CD117, VEGFR-3 and CD44 in haemangiosarcoma compared to haemangioma, suggesting these proteins may be suitable targets. It also found marked mast cell infiltration in haemangioma, indicating a possible role for mast cells in benign vascular neoplasia in dogs.
This document reports on a study comparing the karyotypes and protein profiles of three Trifolium species: T. alexandrinum, T. refeigratum, and T. repens. The results found that T. refeigratum and T. repens both have 16 pairs of chromosomes with one pair containing satellites, while T. alexandrinum has 8 pairs of chromosomes. Analysis of the karyotypes showed differences in symmetry indices between the species. Protein profile analysis via SDS-PAGE revealed clustering of T. alexandrinum separately from the other two species, indicating polymorphic protein bands that differ. The study provides cytological and protein evidence to compare the three clover species
1) Using high resolution telomere fluorescent in situ hybridization, the study found that intratubular germ cell neoplasia and most pure seminomas exhibited short telomeres, while non-seminoma subtypes generally had longer telomeres and a worse prognosis.
2) Among non-seminomas, embryonal carcinoma had the highest proportion of long telomeres and was the only subtype to display an alternative lengthening of telomeres phenotype.
3) The findings indicate that telomere anomalies are an early event in testicular germ cell tumor carcinogenesis and may contribute to tumor initiation and progression. Further investigation of telomeric aberrations could provide new pathways for
This document describes a study on collision tumors of the thyroid gland. Collision tumors are defined as two distinct malignant tumors occurring in the same organ. The study aims to characterize the clinical, pathological and molecular features of collision tumors of the thyroid diagnosed between 2012-2019 at the Malabar Cancer Centre in India. Data on patient demographics, tumor characteristics, treatments, and outcomes will be collected from patient records and tissue samples will be analyzed to detect mutations in genes like BRAF and KRAS. The results of this study aim to increase understanding of these rare thyroid tumors.
The genomes of four tapeworm species reveal adaptations to parasitismJoão Soares
The genomes of four tapeworm species reveal adaptations to parasitism. The genomes range from 115 to 141 megabases and show maintenance of synteny with blood flukes but extreme losses of genes and pathways found in other animals, including 34 homeobox families and stem cell fate determinants. Tapeworms have specialized detoxification pathways, metabolism finely tuned to rely on host nutrients, and expansions of heat shock proteins and known antigen families. The genomes provide insights into tapeworm evolution and identify potential new drug targets, furthering development of urgently needed treatments.
This chapter reviews the use of sex pheromones and male lures in trapping economically important fruit fly species from the genera Anastrepha, Bactrocera, Ceratitis, Dacus, Rhagoletis, and Toxotrypana. It discusses research on identifying pheromones from species such as the Mexican fruit fly (Anastrepha ludens) and Caribbean fruit fly (A. suspensa), though results have been inconsistent. Male lures like methyl eugenol, cuelure, and trimedlure have proven more effective than pheromones for detection and control programs. The chapter provides an overview of the major male lures and factors influencing their
This document summarizes a study that analyzed 12 pairs of monozygotic (identical) twins and 7 pairs of dizygotic (fraternal) twins for concordance of autoimmune diseases like systemic lupus erythematosus (SLE) and Sjögren's syndrome. The study reviewed literature on twin studies of autoimmune diseases to assess genetic and environmental factors. Proteomic analysis of plasma from SLE-discordant monozygotic twins identified potential disease-associated biomarkers. Epigenetic analysis found differential DNA methylation between SLE-affected and healthy twins in genes relevant to SLE pathogenesis. The concordance rate for lupus is higher in identical twins than the general population but not complete, suggesting both
This document summarizes a study of 25 cases of parapharyngeal tumors over a 2 year period. The key findings are:
1) There was a male preponderance (52%) and highest incidence in the 3rd and 5th decades.
2) The most common presenting symptoms were difficulty swallowing (36%) and neck swelling (28%).
3) Fine needle aspiration was performed in 21 cases and correlated with biopsy in 13 cases.
4) CT scan was required for all cases to delineate the size, extent and relationship to surrounding structures.
5) The most common tumor types were neurogenic (44%), salivary origin pleomorphic adenoma (24%), and parag
Justifications for invasive experiments on animals rely on claims that such research is essential for the advancement of biomedical knowledge, for the development of cures to human diseases, or for the evaluation of the toxicity of compounds to which humans are exposed. Until recently, critical evaluations of the accuracy of such claims have been rare. However, a growing body of large-scale systematic reviews have now been published in scientific and medical journals. The outcomes have been consistent: animal experiments have contributed far less than advocates would have us believe.
This presentation summarises these recent results, and comprehensively reviews the alternatives to invasive animal use with biomedical research, toxicity testing, and education.
Published studies are available at www.AnimalExperiments.info.
This document describes a study that characterized the genetic diversity and sexual reproduction capabilities of the fish parasite Ichthyophthirius multifiliis. The researchers sequenced and analyzed three genetic markers (SSUrDNA, nad1_b, and cox-1) from nine I. multifiliis isolates collected in different states. They found that the mitochondrial markers effectively distinguished the isolates and divided them into at least two genetically distinct groups. Analysis of 14 somatic single nucleotide polymorphism sites also showed that none of the nine isolates shared the same composition, suggesting sexual reproduction occurs in the life cycle of I. multifiliis. Compared to related ciliate species, I. multifiliis was found to have lost around 30-38
This study analyzed pulmonary lesions seen in 810 autopsy specimens from patients who died of respiratory diseases. The most common lesions seen were emphysema (40% of cases), tuberculosis (19% of cases), and silicosis (11% of cases). Emphysema was most frequently observed in males aged 20-49 who smoked. Tuberculosis was also more common in males under age 50. Silicosis predominantly affected males aged 30-49. The study concluded that emphysema and tuberculosis are common respiratory diseases in the population, and emphysema and silicosis are linked to smoking and environmental air pollution, respectively.
This document describes the development of a novel MLVA (multilocus variable number tandem repeat analysis) typing scheme for strains of the Ralstonia solanacearum species complex (RSSC) that belong to phylotype III and are found in Africa. The researchers first evaluated an existing 11-locus MLVA scheme (RS3-MLVA11) and found it was not fully suitable for studying the genetic structure of phylotype III populations. They then designed a new optimized 16-locus MLVA scheme (RS3-MLVA16) specific for phylotype III using tandem repeat loci identified from the genome of the reference strain CMR15. When tested on collections of phylotype III strains from various
Similar to Thymomas in Fischer 344N Rats in The National Toxicology Program Database (20)
The Route of Exposure Influences Nasal Lesion Distribution in Rats in NTP Stu...EPL, Inc.
1) The study examined nasal lesion distribution patterns in rats from one inhalation study, two drinking water studies, and three gavage studies conducted by the NTP.
2) Nasal lesions from the inhalation study were predominantly bilateral, dorsal, and located in the anterior nasal sections. Lesions from the drinking water studies were uniformly located in the middle and posterior nasal sections and affected only the olfactory epithelium.
3) Nasal lesions from the gavage studies varied in character and distribution, tended to be more posterior and ventral, and were predominantly unilateral. Lesions in the nasopharyngeal duct only occurred in the gavage studies.
4) Differences in nasal lesion distribution provide clues
Right Ventricular Cardiomyopathy in the Rat - Is There an Association with Ga...EPL, Inc.
This study evaluated whether right ventricular cardiomyopathy in rats was associated with gavage administration. The incidence and severity of cardiomyopathy was compared between gavage and non-gavage rats. The results showed similar rates of cardiomyopathy between gavage and non-gavage rats of both strains studied. Histopathological examination also showed the lesions were identical regardless of administration method. Therefore, the study concluded right ventricular cardiomyopathy in rats is unrelated to the gavage technique of exposure.
Dietary Administration of Diquat for 13 Weeks Does Not Result in a Loss of Do...EPL, Inc.
Dietary Administration of Diquat for 13 Weeks Does Not Result in a Loss of Dopaminergic Neurons in the Substantia Nigra Pars Compacta (SNpc) of C57BL/6J Mice
Renal Tubular Pigmentation Associated with Senna-Related MetabolitesEPL, Inc.
“Renal Tubular Pigmentation Associated with Senna-Related Metabolites.” Willson GA (presenter) Malarkey DE, Allison N, Harris N, Miller RA. The 54th Annual Society of Toxicology Meeting. San Diego, CA. March 25, 2015.
For full-resolution viewing, please open or save as a PDF.
Acquiring Practical Population Estimates of Neurons Through Design-Based Ster...EPL, Inc.
“Acquiring Practical Population Estimates of Neurons Through Design-Based Stereology: Dissecting the Disector.” Zadory D, Burton E, Wolf JC. The 44th Annual Meeting of the Society for Neuroscience. Washington, DC. November 19, 2014.
For full-resolution viewing, please open or save as a PDF.
The National Toxicology Program Nonneoplastic Lesion AtlasEPL, Inc.
The National Toxicology Program (NTP)’s Nonneoplastic Lesion Atlas is a valuable, web-based resource with thousands of high-quality, enlargeable images, diagnostic
guidelines, and preferred NTP terminology for numerous nonneoplastic rodent lesions. The atlas will be used by the NTP and its many pathology partners to standardize lesion diagnosis, terminology, and the way lesions are recorded in NTP studies. The goal is to improve the consistency and accuracy of the diagnosis of nonneoplastic lesions between pathologists and laboratories to improve the organization and utility of the NTP’s nonneoplastic lesion database and, ultimately, our understanding of nonneoplastic lesions. The NTP Nonneoplastic Lesion Atlas is a living document that complements the INHAND publications. In fact, one of the aims of the atlas is to align the NTP terminology with that of the INHAND publications as much as possible. The atlas is also a useful training tool for pathology residents and can be used by any organization to improve their own nonneoplastic lesion database. A total of 56 organs organized into 13 organ systems will be included in the completed project. The atlas is free to the public at http://ntp.niehs.nih.gov/nnl.
Subchronic Inhalation Exposure of Rats to Libby Amphibole and Amosite Asbesto...EPL, Inc.
“Subchronic Inhalation Exposure of Rats to Libby Amphibole and Amosite Asbestos: Effects at 18 Months Post Exposure.” Willson GA (presenter), Dodd DA, Roberts KC, Wall HG, Jarabek AM, Gavett SH. The 33rd Society of Toxicologic Pathology Annual Meeting. Washington, DC. June 22-26, 2014.
“Subchronic Inhalation Exposure of Rats to Libby Amphibole and Amosite Asbestos: Effects at 18 Months Post Exposure.” Dodd DA (presenter), Willson GA, Roberts KC, Wall HG, Jarabek AM, Gavett SH. The 53rd Annual Society of Toxicology Meeting. Phoenix, AZ. March 23-27, 2014.
For full-resolution viewing, please open or save as a PDF.
Immunohistochemical Characterization of ENU-induced Brain Tumors in F344 RatsEPL, Inc.
“Immunohistochemical Characterization of ENU-induced Brain Tumors in F344 Rats.” Moore RR (presenter), Kolenda-Roberts H, Harris NA, Cho YM, Ogawa K, Hardisty JF, Miller RA. The 33rd Society of Toxicologic Pathology Annual Meeting. Washington, DC. June 22-26, 2014.
For full-resolution viewing, please open or save file as a PDF.
Non-lesions, Misdiagnoses, Missed Diagnoses, and Other Interpretive Challenge...EPL, Inc.
“Non-lesions, Misdiagnoses, Missed Diagnoses, and Other Interpretive Challenges in Fish Histopathology Studies: A Guide for Investigators, Authors, Reviewers, and Readers.” Wolf JC (presenter), Baumgartner WA, Blazer VS, Camus AC, Engelhardt JA, Fournie JW, Frasca S, Groman DB, Kent ML, Khoo LH, Law JM, Lombardini ED, Ruehl-Fehlert C, Segner HE, Smith SA, Spitsbergen JM, Weber K, Wolfe MJ. The 33rd Society of Toxicologic Pathology Annual Meeting. Washington, DC. June 22-26, 2014.
For full-resolution viewing, please open or save file as a PDF.
EPL, Inc. - Comparative Anatomy of the EyeEPL, Inc.
Proper evaluation of potential effects of test articles on the eye and its components requires attention to detail in the preparation and examination of specimens. EPL has developed critical capability in histology to produce consistent microscopic sections that facilitate the pathologist’s evaluation of the various segments of the eye. The EPL methodology is applicable to all routes of administration, including intravitreal, topical, or systemic. The veterinary pathologists at EPL have many years of experience evaluating effects on the eye; EPL is the premier source for ocular pathology evaluation. In addition to standard histology and histopathology, special preparations may be included (e.g., special histochemical stains, immunohistochemistry) to further characterize lesions.
The main purpose of a Pathology Peer Review is to improve the quality of the pathology data and narrative. This can be achieved in several ways. A peer review can help to ensure that the data are presented in a manner that meets the requirements of the regulatory agency to which the data will be submitted. A peer review may help to increase the accuracy of the data, thus increasing the confidence in it both for the Sponsor and for the regulatory agencies. This is true whether the study was completed at the Sponsor’s facility, at a Contract Research Organization (CRO), or in an academic laboratory. A peer review can also confirm the target organs identified in the original evaluation and confirm the No Observed Effect Level (NOEL). Our unique PQA software program is a computerized pathology peer review procedure developed at EPL that operates on a portable laptop computer. Study data can be interfaced between the laboratory and EPL’s pathology peer review program through the use of electronic ASCII text files. This assures that the accuracy of the data is maintained during the entire review process and that comparison between the preliminary histopathology data from the laboratory and the pathology quality assurance audit can be made rapidly. In this manner, differences can be easily identified and resolved by the study pathologist and reviewing pathologist, thus allowing the laboratory to complete the draft study report in a timely manner.
Peer review also serves as a source of continuing education and training, for both the study pathologist and the reviewing pathologist. In many cases the study pathologist will have a limited amount of experience, and can benefit from the broader range of experience of the reviewing pathologist. On the other hand, the reviewing pathologist almost always sees something new and learns something different during every peer review. EPL’s team of experienced pathologists have been providing peer review services to the NCI/NTP carcinogenesis testing program and commercially for companies in the pharmaceutical, biotechnology and chemical industry for over 30 years. We provide these services to clients in North America, Europe and Asia. When conducting a peer review, we take our team to the testing laboratory where the study pathologist is located. This eliminates the cost and risk associate with shipping the glass microscope slides and by working directly with the study pathologist to finalize the findings speeds up the reporting process.
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...Oleg Kshivets
Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Adhd Medication Shortage Uk - trinexpharmacy.comreignlana06
The UK is currently facing a Adhd Medication Shortage Uk, which has left many patients and their families grappling with uncertainty and frustration. ADHD, or Attention Deficit Hyperactivity Disorder, is a chronic condition that requires consistent medication to manage effectively. This shortage has highlighted the critical role these medications play in the daily lives of those affected by ADHD. Contact : +1 (747) 209 – 3649 E-mail : sales@trinexpharmacy.com
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
Thymomas in Fischer 344N Rats in The National Toxicology Program Database
1. Figure 7
Brandes, K., Fend, F., Monecke, S., Teifke, J.P., Breuer, W., and Hermanns, W.
(2004). Comparative morphologic and immunohistochemical investigation of
spontaneously occurring thymomas in a colony of European hamsters. Vet
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Thymomas in Fischer 344/N Rats in the National Toxicology Program Database
Gabrielle A Willson1, Rebecca R. Moore1, Hiroaki Nagai2, Rodney A. Miller1, Jerry F. Hardisty1, Neil Allison1, David E. Malarkey2
1Experimental Pathology Laboratories, Inc., Research Triangle Park, NC, USA
2Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
Figure 3
Thymoma is an uncommon tumor in most strains of rats and mice.
Primary tumors of the thymus of Sprague-Dawley-derived rats
(strain Tif:RAI) were reported from 7 different long-term studies
(Naylor, et al., 1988). In that study, 192 primary thymic tumors were
identified (out of 4281 animals), of which 171 appeared benign and
21 appeared malignant. In the F344/N rat spontaneously occurring
thymomas are rare, and most of those have been reported to be
benign (Stefanski, Elwell, and Stromberg, 1990; Haseman, Hailey,
and Morris, 1998). The literature contains no reports of large studies
of thymoma in F344/N rats. The purpose of this study is to describe
the morphological features, incidence, and behavior of thymoma in
F344/N rats in NTP studies.
Two hundred seventy-seven thymomas recorded in chronic studies in
the NTP archives database were reviewed. No thymomas were
recorded in any of the subchronic studies. Thymomas in F344/N rats
in this survey were rare occurrences (<0.2% incidence). No
occurrences of this tumor were found to be associated with
treatment. Thymomas occurred more commonly in male rats
(156/277 [56.3%]) than in female rats (121/277 [43.7%]). Benign
thymomas comprised 84.8% (235/277) of the thymomas reviewed,
and the remaining 15.2% (42/277) were diagnosed as malignant
thymomas based upon metastasis, unequivocal tissue invasion, or
cytological malignant features (Table 1). In male rats 27/156 (17.3%)
thymomas were malignant, and in female rats 15/121 (12.4%) were
malignant. Metastases were observed in 14 of the 42 animals with
malignant thymomas, and in all 14 cases metastatic lesions were
observed in the lung. Metastases also were present in the lymph
node of 1 animal and in the liver of another animal. All of the
malignant thymomas that metastasized had features of the main
tumor mass and no malignant epithelial neoplasms were present in
other organs. Seventeen of the remaining 28 malignant thymomas
that exhibited no metastases were diagnosed due to their
unequivocal tissue invasion, and 11 cases were diagnosed based
upon cytological features, such as pleomorphism, cellular atypia,
karyomegaly, anisokaryosis, prominent nucleoli, and increased
mitoses. These cytologic features typically associated with
malignancy seemed to have little to no relationship to a propensity for
invasion or metastasis.
Thymomas in Fischer 344/N rats were morphologically
heterogeneous but could be divided into 6 general categories
according to morphologic features (Table 2). Most tumors displayed
a mixture of more than one morphologic pattern, and these were
grouped according to the predominant pattern. The most common
morphologic pattern consisted of epithelial cells arranged in cords
and tubules and was present in 155/277 (56.0%) of the tumors in this
review (Figure 1). This was followed by thymomas with a
predominantly spindloid pattern, which occurred with a frequency of
79/277 (28.5%) (Figures 2 and 3). A papillary pattern was observed
in 17/277 (6.1%) of the tumors and was frequently associated with
cystic features (Figure 4). A squamous epithelial pattern was present
in 12/277 (4.3%) of the tumors (Figure 5). A myoid pattern was
present in 11/277 (4.0%) of the tumors (Figure 6A). The myoid cell is
a striated muscle cell which exhibits expression of desmin (Figures
6B and 6C). While it is possible that myoid cells within the thymomas
in this series represented invasion of pre-existing muscle, myoid
differentiation of neoplastic cells could not be ruled out. A
neuroendocrine pattern was observed in only 3/277 (1.1%) of the
tumors (Figure 7). No particular pattern was unequivocally correlated
with a metastatic or invasive propensity.
Four benign thymomas (4/228; 1.8%), 11 malignant thymomas
without metastasis (11/28; 39.3%), and 11 malignant thymomas with
metastasis (11/14; 78.6 %) were considered to be the cause of death.
The survival days of animals with malignant thymomas were less
than those of animals with benign thymomas (Table 3).
Figure 2
Results
Thymoma is defined as the neoplastic proliferation of thymic
epithelial cells. By virtue of the cellular composition of the thymus,
thymomas contain varying numbers of non-neoplastic lymphocytes.
Various classification schemes have been described in veterinary
medicine, and most are based upon histomorphological features.
One such scheme creates divisions based upon the relative
proportions of lymphocytes and epithelial cells, thus specifying tumor
types as either epithelial type, mixed epithelial and lymphoid cell
type, or “pure” lymphoid type (containing scattered epithelial cells to
distinguish it from well-differentiated lymphoma) (Greaves, 2012).
Others suggest that thymomas are divided into two types, consisting
of tumors with and without medullary differentiation (Kuper, Beems,
and Hollanders, 1986; Kuper and Beems, 1990). Tumors exhibiting
lobular, medullary differentiation have pale staining areas containing
fewer lymphocytes, fibrous trabeculae, and may contain epithelial
cells forming cords, tubules, and cysts. Thymomas without medullary
differentiation consist of a mixture of small lymphocytes and epithelial
cells without a lobular architecture. While epithelial cell morphology
can be quite variable, cellular atypia has been found to be rare
(Kuper and Beems, 1990). Epithelial cells of thymomas can form
several morphological patterns, which have been described by one
author as epidermoid (non-keratinizing squamous epithelium);
squamoid (with keratinization); papillary; ribbons, cords, or tubules;
spindloid; endocrine-like; neuroendocrine; and myoid (Pearse, 2006).
Thymoma is an uncommon tumor in most strains of rats and mice.
Primary tumors of the thymus of Sprague-Dawley-derived rats
(strain: Tif:RAI) were reported from 7 different long-term or lifespan
studies (Naylor, et al., 1988). In that study, 192 primary thymic
tumors were identified (out of 4281 thymuses), of which 171 were
classified as benign and 21 were called malignant. In the F344/N rat
spontaneously occurring thymomas are rare, and most of those have
been reported to be benign (Stefanski, Elwell, and Stromberg, 1990;
Haseman, Hailey, and Morris, 1998). The purpose of this study is to
describe the morphological features, incidences, and behavior of
thymoma in Fischer 344/N rats in NTP studies.
Introduction
Figure 1
Figure 4
Thymomas are neoplasms of thymic epithelial cell origin which may
contain variable numbers of non-neoplastic lymphocytes. Thymomas
appear grossly as a firm, smooth mass in the anterior mediastinum,
and compression of the surrounding tissues may or may not be
present. These tumors are rare in humans and most lab animals. In
the Fischer 344/N rat, thymomas are rare and are said to occur with
no apparent sex difference (Stefanski, Elwell, and Stromberg, 1990),
although in this review more thymomas were observed in male rats.
There is no meaningful established classification system of
thymomas in veterinary medicine, whereas in human medicine there
is the widely used classification system established by the World
Health Organization (WHO) (Rosai and Sobin, 1999). Nevertheless,
the WHO system has been adapted for use in one of the largest
hamster thymoma papers to date (Brandes et al., 2004).
Diagnostic paradigms have been described for rat thymomas,
including those dividing them according to the proportions of
epithelial and lymphoid cells (Greaves, 2012), as well as divisions
based upon thymomas with and without medullary differentiation
(Kuper and Beems, 1990; Kuper, Beems, and Hollanders, 1986).
While understandable and useable, these paradigms do not seem to
add significantly to our ability to interpret the rat thymoma in relation
to toxicologic or biological significance.
The thymomas in this review were variable in microscopic
appearance and were separated into 6 categories based upon
morphological patterns. Although this could be done with some
consistency, there was no apparent difference in biological behavior
between the categories. Since separating thymomas into several
sub-classifications appears to have limited, if any, scientific relevance
in terms of biological behavior, it seems adequate to designate them
only as benign or malignant until new information is obtained.
Classifying thymomas as benign or malignant traditionally has been
based upon cytologic features and biological behavior such as
invasion and metastasis as discussed in two volumes of International
Classification of Rodent Tumors (Hailey et al., 1993; Frith et al.,
2001). In this review there was little evidence that cytologic features
typically associated with malignancy were necessarily correlated with
invasion or metastasis
Discussion
References
The NTP studies evaluated for this review ended at 104 to 105
weeks for chronic studies and 13 weeks for subchronic studies.
Complete necropsies were performed on all animals. All gross
lesions and approximately 43 tissues were collected, fixed in 10%
neutral buffered formalin, stained with H&E, and examined. Thymic
tissue and/or thymic masses were collected from all rats on each
study.
The NTP historical databases were reviewed for the diagnosis of
benign thymoma, malignant thymoma, and thymoma. The
databases contained data on ~190,000 Fischer 344/N rats (~175,000
rats from chronic studies and ~15,000 rats used in subchronic
studies). All sections of thymomas were evaluated for unique
morphologic features, patterns of growth, and the presence or
absence of invasion and/or metastasis that could be used to
categorize them as benign or malignant. Tabulation of data was
designed to determine thymoma occurrences in male and female
rats, classification of tumors as benign or malignant, and to
characterize general morphologic patterns that may relate to
determining malignancy.
The classification of the neoplasms as benign or malignant was
based upon tumor expansion and invasion of surrounding tissues, as
well as presence of metastatic lesions. Thymomas were classified as
benign when they were confined to the mediastinal space, discrete,
exhibited an expansile non-invasive growth pattern, and there was no
evidence of metastasis. Extension into the mediastinal fat was
considered a benign feature as long as there was connection to the
main tumor mass and as long as the other benign tumor criteria were
met. Malignant thymomas were characterized by implantation on
serosal surfaces, metastasis to other organs, invasion of adjacent
tissues (body wall, diaphragm, or thoracic organs), and/or infiltration
of mediastinal fat with nests of neoplastic cells but no apparent
connection with the main tumor mass.
Methods
Abstract
Figure 6
Figure 5
Figure 1A. Benign thymoma from a male F344/N rat from a 2-year NTP
study. (H&E)
Figure 1B. Higher magnification of 1A, the neoplastic epithelial cells form
cords and tubules. (H&E)
Figure 2. Spindloid pattern in a malignant thymoma from a female F344/N
rat from a two-year NTP study. (H&E)
Figure 3. Lung metastasis from a malignant thymoma in a male F344/N rat
from a 2-year study. Sheets of elongated neoplastic cells form a spindloid
pattern. (H&E)
Figure 4. Benign thymoma is from a male F344/N rat from a 2-year study.
Neoplastic epithelial cells form papillary projections, which protrude into
cystic spaces. There are small clusters of non-neoplastic lymphocytes
interspersed with the neoplastic cells. (H&E)
Figure 5. Malignant thymoma is from a male F344/N rat from a 2-year
study. The neoplastic epithelial cells form a squamous pattern. (H&E)
Figure 6A. Malignant thymoma is from a female F344/N rat from a 2-year
study. The neoplastic epithelial cells form a myoid pattern. (H&E)
Figure 6B. Immunohistochemical staining of neoplasm from 6A showing
expression of desmin in myoid cells. (Desmin)
Figure 6C. Immunohistochemical staining of neoplasm from 6A showing
expression of desmin with prominent cross striations in myoid cells.
(Desmin)
Figure 7. Benign thymoma is from a female F344/N rat from a 2-year study.
Packets of elongated neoplastic cells form a neuroendocrine pattern.
(H&E)
Benign
Malignant
without metastasis with metastasis
Number of animals 228 a 28 14
Mean survival days b 713 ± 4 609 ± 27 506 ± 42
Cause of death: thymoma 4 11 11
Sacrifice type
Natural death 16 8 8
Moribund sacrifice 48 9 6
Terminal sacrifice 164 11 0
a Seven animals were not included in this table because there were 2 accidental deaths
and 5 animals were sacrificed for interim necropsy.
b Study days on which animals were sacrificed. Value shown is group mean ± S.E.
Morphologic pattern Benign Malignant Total
Cords/Tubules 139 16 155
Spindloid 66 13 79
Papillary 17 0 17
Squamous 5 7 12
Myoid 6 5 11
Neuroendocrine 2 1 3
Table 2. The morphologic patterns of thymomas
Benign Malignant Total
Male 129 27 (10*) 156
Female 106 15 (4*) 121
Total 235 42 (14*) 277
Table 1. The incidence of thymomas in male and
female Fischer 344/N Rats
Table 3. Correlation of the malignancy of thymoma with
survival days, cause of death and sacrifice type
*The number within parentheses denotes the number of malignant thymomas with metastasis.
A B
C
A B
Grateful thanks for assistance with this poster to Karen Cimon, Kim
Pernicka, Maureen Puccini and Emily Singletary, of EPL and Lois
Wyrick of Image Associates.
Acknowledgments