This study evaluated four recombinant proteins representing the 19 kDa C-terminal region of the Plasmodium vivax merozoite surface protein-1 (MSP119) for detecting P. vivax antibodies in human serum samples. The sensitivity of an ELISA using the recombinant proteins to detect antibodies in 200 samples from individuals with P. vivax infection ranged from 90-93.5%. Specificity using control samples without P. vivax exposure was 98.3-100%. The study demonstrates the potential of an ELISA using recombinant MSP119 proteins for serological detection of P. vivax infection.
1) The study evaluated the performance of the OptiMal malaria rapid diagnostic test under different storage conditions of 25°C, 30°C, and 39°C for 24, 48, and 72 hours.
2) The test detected all 111 positive blood samples except for 2 low parasitemia Plasmodium malariae samples.
3) The study suggests that the OptiMal test can be used for malaria diagnosis in Brazilian regions, though further research is needed to evaluate its performance under different environmental conditions like humidity.
Infective endocarditis is a life-threatening disease caused by bacterial infection of the endothelium and cardiac valves, either native or prosthetic. In the present work the role of the new microbiological techniques (techniques of detection and amplification of the subunit 16 ribosomal sRNA by means of the chain reaction of the polymerase in blood or tissue, fluorescent in situ hybridization, and matrix-assisted laser is reviewed desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF MS) in the diagnosis of infective endocarditis.
This study evaluated the frequency of asymptomatic Plasmodium carriers (APCs) among blood donors in four blood banks in the Brazilian Amazon region. Blood samples from 400 donors who passed screening were tested using PCR to detect Plasmodium DNA. The positivity rate varied from 1-3% between blood banks, with an overall rate of 2.3%. All positive samples contained mixed infections of P. vivax and P. falciparum. While screening methods used by the blood banks did not detect the infections, PCR revealed its superiority for detecting low levels of parasites. The results emphasize the need to improve screening for APCs in blood banks in malaria endemic areas to control transfusion-transmitted malaria.
This document discusses a study analyzing the neutralizing antibody response in convalescent plasma from 3 survivors of Ebola virus disease (EVD). The plasma was tested for neutralizing activity against variants of Ebola virus as well as other ebolaviruses using a glycoprotein-pseudotyped lentiviral system with both full-length and cleaved glycoprotein. The results showed low neutralizing activity against full-length glycoproteins but broad and potent neutralizing activity against the cleaved glycoprotein forms, suggesting conserved epitopes are exposed upon cleavage. This could inform development of immunogens to induce broadly neutralizing antibodies.
Naturally acquired plasmodium knowlesi malaria in human, thailand[1]Prasit Chanarat
1) A 38-year-old Thai man contracted Plasmodium knowlesi malaria after spending time in a forested area of southern Thailand near the Thai-Myanmar border.
2) Microscopic examination of blood smears showed malaria parasites consistent with P. malariae. However, PCR and sequencing of the small subunit rRNA and mitochondrial cytochrome b genes confirmed the species as P. knowlesi.
3) This is the first reported case of naturally acquired P. knowlesi malaria in humans in Thailand, indicating that wild primate populations may serve as reservoirs for simian malaria parasites capable of infecting humans.
The document discusses a study aiming to rapidly diagnose bacterial sepsis in high-risk patients. The study used polymerase chain reaction (PCR) of the 16S ribosomal DNA gene and measurement of the DcR3 serum level within 48 hours of hospitalization. Of 52 patients, 25 tested positive by PCR and had elevated DcR3 levels, indicating sepsis. PCR results correlated well with blood culture results but provided faster results. The study suggests PCR and DcR3 measurement provide rapid and specific diagnosis of bacterial sepsis.
This document summarizes a study that analyzed Duffy blood group genotypes in Plasmodium vivax malaria patients and blood donors in four areas of the Brazilian Amazon region. The study found:
1) A high frequency of the FYA/FYB genotype in both patients and donors, followed by FYB/FYB.
2) Some Duffy genotypes showed significant differences in frequency between patients and donors.
3) Individuals with the FYA/FYB genotype may have higher susceptibility to malaria, while the presence of the FYB-33 allele could provide resistance.
Antibiotic resistance and virulence genes in enterococcusMohamed Hassan
This document summarizes a study on antibiotic resistance and virulence genes in Enterococcus strains isolated from hospitals in Saudi Arabia. 89 bacterial isolates were obtained from hospital patients, of which 12 were Enterococcus species. These Enterococcus isolates were tested for antibiotic resistance, identified using specific gene primers, and characterized using repetitive sequence-based PCR (Rep-PCR). The results showed that 58.3% of isolates were Enterococcus faecium, 16.6% were Enterococcus durans, and 25.1% were other Enterococcus species. 67% of isolates showed multi-drug resistance. Virulence genes were also detected in some isolates. 16S rDNA sequencing was used to further identify the isolates. The isolates exhibited genetic diversity
1) The study evaluated the performance of the OptiMal malaria rapid diagnostic test under different storage conditions of 25°C, 30°C, and 39°C for 24, 48, and 72 hours.
2) The test detected all 111 positive blood samples except for 2 low parasitemia Plasmodium malariae samples.
3) The study suggests that the OptiMal test can be used for malaria diagnosis in Brazilian regions, though further research is needed to evaluate its performance under different environmental conditions like humidity.
Infective endocarditis is a life-threatening disease caused by bacterial infection of the endothelium and cardiac valves, either native or prosthetic. In the present work the role of the new microbiological techniques (techniques of detection and amplification of the subunit 16 ribosomal sRNA by means of the chain reaction of the polymerase in blood or tissue, fluorescent in situ hybridization, and matrix-assisted laser is reviewed desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF MS) in the diagnosis of infective endocarditis.
This study evaluated the frequency of asymptomatic Plasmodium carriers (APCs) among blood donors in four blood banks in the Brazilian Amazon region. Blood samples from 400 donors who passed screening were tested using PCR to detect Plasmodium DNA. The positivity rate varied from 1-3% between blood banks, with an overall rate of 2.3%. All positive samples contained mixed infections of P. vivax and P. falciparum. While screening methods used by the blood banks did not detect the infections, PCR revealed its superiority for detecting low levels of parasites. The results emphasize the need to improve screening for APCs in blood banks in malaria endemic areas to control transfusion-transmitted malaria.
This document discusses a study analyzing the neutralizing antibody response in convalescent plasma from 3 survivors of Ebola virus disease (EVD). The plasma was tested for neutralizing activity against variants of Ebola virus as well as other ebolaviruses using a glycoprotein-pseudotyped lentiviral system with both full-length and cleaved glycoprotein. The results showed low neutralizing activity against full-length glycoproteins but broad and potent neutralizing activity against the cleaved glycoprotein forms, suggesting conserved epitopes are exposed upon cleavage. This could inform development of immunogens to induce broadly neutralizing antibodies.
Naturally acquired plasmodium knowlesi malaria in human, thailand[1]Prasit Chanarat
1) A 38-year-old Thai man contracted Plasmodium knowlesi malaria after spending time in a forested area of southern Thailand near the Thai-Myanmar border.
2) Microscopic examination of blood smears showed malaria parasites consistent with P. malariae. However, PCR and sequencing of the small subunit rRNA and mitochondrial cytochrome b genes confirmed the species as P. knowlesi.
3) This is the first reported case of naturally acquired P. knowlesi malaria in humans in Thailand, indicating that wild primate populations may serve as reservoirs for simian malaria parasites capable of infecting humans.
The document discusses a study aiming to rapidly diagnose bacterial sepsis in high-risk patients. The study used polymerase chain reaction (PCR) of the 16S ribosomal DNA gene and measurement of the DcR3 serum level within 48 hours of hospitalization. Of 52 patients, 25 tested positive by PCR and had elevated DcR3 levels, indicating sepsis. PCR results correlated well with blood culture results but provided faster results. The study suggests PCR and DcR3 measurement provide rapid and specific diagnosis of bacterial sepsis.
This document summarizes a study that analyzed Duffy blood group genotypes in Plasmodium vivax malaria patients and blood donors in four areas of the Brazilian Amazon region. The study found:
1) A high frequency of the FYA/FYB genotype in both patients and donors, followed by FYB/FYB.
2) Some Duffy genotypes showed significant differences in frequency between patients and donors.
3) Individuals with the FYA/FYB genotype may have higher susceptibility to malaria, while the presence of the FYB-33 allele could provide resistance.
Antibiotic resistance and virulence genes in enterococcusMohamed Hassan
This document summarizes a study on antibiotic resistance and virulence genes in Enterococcus strains isolated from hospitals in Saudi Arabia. 89 bacterial isolates were obtained from hospital patients, of which 12 were Enterococcus species. These Enterococcus isolates were tested for antibiotic resistance, identified using specific gene primers, and characterized using repetitive sequence-based PCR (Rep-PCR). The results showed that 58.3% of isolates were Enterococcus faecium, 16.6% were Enterococcus durans, and 25.1% were other Enterococcus species. 67% of isolates showed multi-drug resistance. Virulence genes were also detected in some isolates. 16S rDNA sequencing was used to further identify the isolates. The isolates exhibited genetic diversity
The document describes the development of multiplex qPCR assays that can rapidly and reliably detect Bacillus anthracis, Francisella tularensis, and Yersinia pestis. The assays target pathogen-specific DNA sequences and include an internal control (B. thuringiensis cry1 gene) to control for DNA extraction and amplification. Validation showed the assays can simultaneously detect 3 pathogen targets with high sensitivity and specificity, and that inclusion of the internal control reduces the risk of false negatives. The assays provide a useful tool for the detection of these high-risk pathogens.
Diagnosis of Capnocytophaga canimorsus Sepsis by Whole Genome Next Generation...brad.kuntscher
This case report describes a 60-year-old man who presented with septic shock. A novel whole genome next-generation sequencing assay identified Capnocytophaga canimorsus in the patient's plasma within 24 hours, providing a presumptive diagnosis. Conventional blood cultures later grew C. canimorsus and 16S rRNA sequencing confirmed the identification after multiple attempts. This demonstrates the potential of next-generation sequencing to rapidly diagnose infections caused by fastidious pathogens directly from patient samples.
frequency of cryptococcus species and varieties in méxicoIPN
This study analyzed 211 Cryptococcus strains isolated from patients in Mexico City hospitals between 1989-1998. C. neoformans was the dominant species isolated (97.15%), followed by C. albidus and C. uniguttulatus. Most strains were isolated from cerebral spinal fluid (92.5%) and AIDS was the main predisposing factor (85%). The disease was found to predominantly affect males (87.3%) in their third (33.8%) and fourth (37.5%) decades of life. When compared to other Latin American countries, the isolation frequency of C. neoformans var. neoformans and var. gattii in Mexico was most similar to Brazil.
Medical Conferences, Pharma Conferences, Engineering Conferences, Science Conferences, Manufacturing Conferences, Social Science Conferences, Business Conferences, Scientific Conferences Malaysia, Thailand, Singapore, Hong Kong, Dubai, Turkey 2014 2015 2016
Global Research & Development Services (GRDS) is a leading academic event organizer, publishing Open Access Journals and conducting several professionally organized international conferences all over the globe annually. GRDS aims to disseminate knowledge and innovation with the help of its International Conferences and open access publications. GRDS International conferences are world-class events which provide a meaningful platform for researchers, students, academicians, institutions, entrepreneurs, industries and practitioners to create, share and disseminate knowledge and innovation and to develop long-lasting network and collaboration.
GRDS is a blend of Open Access Publications and world-wide International Conferences and Academic events. The prime mission of GRDS is to make continuous efforts in transforming the lives of people around the world through education, application of research and innovative ideas.
Global Research & Development Services (GRDS) is also active in the field of Research Funding, Research Consultancy, Training and Workshops along with International Conferences and Open Access Publications.
International Conferences 2014 – 2015
Malaysia Conferences, Thailand Conferences, Singapore Conferences, Hong Kong Conferences, Dubai Conferences, Turkey Conferences, Conference Listing, Conference Alerts
Prevalence of Rota Virus Detection by Reverse TranscriptasePolymerase Chain R...IOSRJPBS
The present study was conducted for the period from 1/6/2016 to 20/1/2017 in Baquba city. The study aimed to detection of rotavirus in stool specimens of children fewer than five age and also explore the effects of certain demographic factors on the detection rates by revers transcriptase- polymerase chain reaction. The study included 49 patients with acute diarrhea, 32 were male and 17 were female. The age range was two months to 5 years. Demographic information on the patients regarding age, sex, residence, type of feeding and source of drinking water were collected from their parents. Stool specimens were collected from each patients and. Detection of rotavirus in stool specimens was done by conventional reverse transcriptase polymerase chain reaction (RT-PCR). The results of present study showed that the overall infection rate by rotavirus among patients with acute diarrhea by RT-PCR tests was 93.88%. The highest infection rate was recorded among those >10-≤15 months of age. None of the results showed significantly difference between female and male, PCR (88% vs 96.87%). Likewise, there was insignificantly difference between urban and rural residence, PCR (95.65% vs 92.30%). The results revealed insignificantly higher infection rate among patients (those below 2 years) feed mixing (91.66%) and bottled (100%) compared to that breast feeding (77.77%) by RT-PCR. The rotavirus infection rate was insignificantly higher among patients consuming municipal water for drinking (97.22%) compared to those consuming bottled water (84.61%) by the RT-PCR. The study concluded that rotavirus was detected in high rates among children less than 5 years old with acute diarrhea in Baquba city, particularly those less than 2 year old.
Yeasts such as Candida are common causes of bloodstream infections in ICU patients. Candida infections in the ICU have a high mortality rate of 15-25% and are the 4th most common cause of hospital-acquired bloodstream infections. Diagnosis can be challenging due to low sensitivity of blood cultures, but newer tests such as PCR, antigen detection assays, and MALDI-TOF mass spectrometry provide more rapid detection of Candida compared to standard culture methods. The presence of risk factors such as abdominal surgery, central venous catheters, antibiotics use, and prolonged ICU stay increase the risk of developing Candida bloodstream infections in critically ill patients.
This document provides an outline for a presentation on HCV genotyping methods. It discusses the morphology and characteristics of HCV, its history and structure. It describes the six genotypes of HCV and their geographical distribution. It also discusses mutants of HCV, clinical importance of genotypes, laboratory diagnosis, and different methods for genotyping including direct sequencing, RFLP typing of the 5'UTR, and line probe assay (LiPA). The advantages of LiPA include it being easy, less time consuming and capable of reliably genotyping HCV RNA directly from clinical samples.
Molecular biomarkers can be used for several purposes in infectious disease research and clinical practice. These include detecting pathogens, measuring antibody responses, identifying markers of virulence, resistance, and disease severity, and understanding human immune responses and genetic susceptibility. Challenges include lack of sensitivity, mobile genetic elements, and changes in RNA sequences. Whole genome sequencing allows investigation of microbial phylogeny, evolution, and virulence factors.
This document discusses various laboratory diagnostic techniques for parasitic infections. It begins by noting that light microscopy remains the standard for diagnosis of most parasites, but nucleic acid tests are becoming more popular. Immunological diagnosis using techniques like ELISA and rapid diagnostic tests (RDTs) have advantages like speed and ease of use. The document then examines specific techniques for diagnosing various parasites like malaria, cryptosporidiosis, amoebiasis, trichomoniasis, lymphatic filariasis, and leishmaniasis. It discusses advantages and limitations of different antigen and antibody detection methods.
Novel research aimed at finding a cure for AIDS requires animal models responding to human antiretroviral drugs. However, there have been few antiretrovirals cross-active against the simian viruses. In this study, we expanded the arsenal of drugs active against the simian retrovirus SIVmac251 and showed that this virus is inhibited by the protease inhibitor, darunavir, and the CCR5 blocker, maraviroc. Administration of these two drugs in combination with the reverse transcriptase inhibitors, tenofovir and emtricitabine, and the integrase inhibitor, raltegravir, resulted in prolonged plasma viral loads below assay detection limits, and, surprisingly, restricted the viral reservoir, a marker of which is viral DNA. We then decided to employ this multidrug regimen (termed “highly intensified ART”) in order to increase the potency of a previous strategy based on the gold drug auranofin, which recently proved able to restrict the viral reservoir in vivo. A short course of highly intensified ART following the previous treatment resulted, upon therapy suspension, in a remarkably spontaneous control of the infection, that may pave the way to a persistent suppression of viremia in the absence of ART. These results corroborate the robustness of the macaque AIDS model as a vanguard for potentially future treatments for HIV in humans.
A single-reaction quadruplex qPCR assay was developed that can rapidly detect and differentiate Burkholderia mallei and Burkholderia pseudomallei. The assay uses three signature sequences - a multicopy transposase sequence common to both species for sensitive detection, and two unique sequences for species differentiation. It also incorporates an internal control for DNA extraction and amplification using Bacillus thuringiensis. The assay enables detection of less than 1 genome equivalent and differentiation of B. mallei and B. pseudomallei with high sensitivity and reliability for diagnostic and surveillance purposes.
This study compared microscopy and PCR techniques for diagnosing malaria in suspected patients in Nepal. Of 824 suspected malaria cases tested, 19.2% were confirmed by microscopy, with most being P. vivax (10.9%) or P. falciparum (7.7%) infections. PCR testing of 132 blood samples detected more cases than microscopy, including some microscopy-negative samples. PCR was better able to detect mixed infections and identified some samples to the species level that microscopy identified only as Plasmodium. While PCR is more sensitive for detection and useful for research, microscopy remains the standard for routine diagnosis due to its lower cost and feasibility.
Presentation 2.1 Update June 2016 on AHPND and EHP research in Thailand (Dr T...ExternalEvents
http://www.fao.org/documents/card/en/c/28b6bd62-5433-4fad-b5a1-8ac61eb671b1/
FAO Second International Technical Seminar/Workshop on Acute hepatopancreatic necrosis disease (AHPND) There is a way forward! FAO Technical Cooperation Programme: TCP/INT/3501 and TCP/INT/3502.
Plasma levels of circulating nucleic acids (CNAs) were significantly higher in patients with Plasmodium vivax malaria compared to healthy donors. CNAs levels strongly correlated with clinical markers of malaria morbidity, including fever and thrombocytopenia. Higher CNAs levels were also associated with a more severe clinical presentation based on a scoring system. These findings suggest that CNAs have potential as sensitive biomarkers for assessing severity of P. vivax malaria infections.
The document summarizes preliminary research toward developing a method for stably transfecting the malaria parasite Plasmodium vivax. The researchers tested various transfection conditions and found the highest parasite survival rates using the Amaxa Nucleofector program U-033 and pre-loading erythrocytes with DNA. However, no fluorescent parasites were observed, likely due to the low efficiency of Plasmodium transfection. Future work aims to increase parasite numbers for transfection and further optimize methods.
Dr. Kurt Stevenson - Antimicrobial Resistance Surveillance and Management in ...John Blue
Antimicrobial Resistance Surveillance and Management in Hospital and Community Settings - Issues for Human Population Medicine - Dr. Kurt Stevenson, The Ohio State University Medical Center, from the 2012 NIAA One Health Approach to Antimicrobial Resistance and Use Symposium, October 26-27, 2012, Columbus, OH, USA.
More presentations at:
http://www.trufflemedia.com/agmedia/conference/2012-one-health-to-approach-antimicrobial-resistance-and-use
This study evaluated the use of quantitative PCR (qPCR) to genotype single nucleotide polymorphisms (SNPs) near a mutation in the RTEL1 gene for preimplantation genetic diagnosis of Dyskeratosis Congenita, compared to the standard method using short tandem repeats (STRs). The standard STR method misdiagnosed 3 of 14 embryos due to recombination between the distant STR marker and mutation. In contrast, qPCR of closely linked SNPs identified recombination in 9 of 17 embryos and correctly diagnosed all embryos. This case demonstrates that qPCR of SNPs provides improved sensitivity over STRs for detecting recombination near telomeric mutations.
Can Meropenem Heteroresistance in OXA-48-Producing K. pneumoniae be Inferred...PROANTIBIOTICOS
This document discusses the phenomenon of heteroresistance in bacteria and analyzes whether it occurs in OXA-48 producing Klebsiella pneumoniae. It finds that population analysis profile curves did not show evidence of heteroresistance in various clones of OXA-48 K. pneumoniae, as cells growing at high carbapenem concentrations were resistant mutants rather than a heteroresistant subpopulation. The presence of colonies growing in the inhibition zone of meropenem E-tests was also not indicative of heteroresistance in this case. In conclusion, heteroresistance was not observed in OXA-48 producing K. pneumoniae.
The study examines the spatial patterns of malaria among the Bharia tribe in Tamia, Chhindwara district of Madhya Pradesh, India. Tamia has over 85% Bharia tribal population and is surrounded by forests and hills providing favorable conditions for malaria. Malaria is caused by four plasmodium parasites transmitted via Anopheles mosquitoes. The most common types in the area are Plasmodium falciparum and Plasmodium vivax.
Secondary data on malaria cases from 2006-2010 was collected from local health centers and analyzed by species, gender, and age. Results show that total malaria cases increased five-fold from 2006 to 2010 likely due to drug resistance. P. fal
The document discusses the determination of diffusion constants in boronated powder metallurgy samples of the iron-carbon-copper system. Experiments were conducted on powdered samples with 0.1% carbon and 1-3% copper. The thickness of the boride layers formed after boronation at temperatures of 920-980°C were measured. The data was used to calculate the activation energy (Q) and pre-exponential factor (Do) based on parabolic growth curves. The results show that Q increases with sample density from 5.8 to 7 g/cm3. Adding up to 2% copper reduces Q values, but higher copper concentrations increase Q similar to pure iron samples.
This study aimed to investigate the presence of arboviruses like dengue virus in clinical samples from 111 malaria patients in the Amazon region of Brazil.
Dengue virus serotype 2 was detected in two patients from Novo Repartimento, Pará who also had active Plasmodium vivax malaria infections. Despite limited data, concurrent dengue and malaria infections are likely more common in the Amazon region than detected, as both diseases co-circulate and have similar transmission vectors and clinical presentations, making dual diagnosis possible. Further research is needed to better understand the frequency of co-infection in this region.
The document describes the development of multiplex qPCR assays that can rapidly and reliably detect Bacillus anthracis, Francisella tularensis, and Yersinia pestis. The assays target pathogen-specific DNA sequences and include an internal control (B. thuringiensis cry1 gene) to control for DNA extraction and amplification. Validation showed the assays can simultaneously detect 3 pathogen targets with high sensitivity and specificity, and that inclusion of the internal control reduces the risk of false negatives. The assays provide a useful tool for the detection of these high-risk pathogens.
Diagnosis of Capnocytophaga canimorsus Sepsis by Whole Genome Next Generation...brad.kuntscher
This case report describes a 60-year-old man who presented with septic shock. A novel whole genome next-generation sequencing assay identified Capnocytophaga canimorsus in the patient's plasma within 24 hours, providing a presumptive diagnosis. Conventional blood cultures later grew C. canimorsus and 16S rRNA sequencing confirmed the identification after multiple attempts. This demonstrates the potential of next-generation sequencing to rapidly diagnose infections caused by fastidious pathogens directly from patient samples.
frequency of cryptococcus species and varieties in méxicoIPN
This study analyzed 211 Cryptococcus strains isolated from patients in Mexico City hospitals between 1989-1998. C. neoformans was the dominant species isolated (97.15%), followed by C. albidus and C. uniguttulatus. Most strains were isolated from cerebral spinal fluid (92.5%) and AIDS was the main predisposing factor (85%). The disease was found to predominantly affect males (87.3%) in their third (33.8%) and fourth (37.5%) decades of life. When compared to other Latin American countries, the isolation frequency of C. neoformans var. neoformans and var. gattii in Mexico was most similar to Brazil.
Medical Conferences, Pharma Conferences, Engineering Conferences, Science Conferences, Manufacturing Conferences, Social Science Conferences, Business Conferences, Scientific Conferences Malaysia, Thailand, Singapore, Hong Kong, Dubai, Turkey 2014 2015 2016
Global Research & Development Services (GRDS) is a leading academic event organizer, publishing Open Access Journals and conducting several professionally organized international conferences all over the globe annually. GRDS aims to disseminate knowledge and innovation with the help of its International Conferences and open access publications. GRDS International conferences are world-class events which provide a meaningful platform for researchers, students, academicians, institutions, entrepreneurs, industries and practitioners to create, share and disseminate knowledge and innovation and to develop long-lasting network and collaboration.
GRDS is a blend of Open Access Publications and world-wide International Conferences and Academic events. The prime mission of GRDS is to make continuous efforts in transforming the lives of people around the world through education, application of research and innovative ideas.
Global Research & Development Services (GRDS) is also active in the field of Research Funding, Research Consultancy, Training and Workshops along with International Conferences and Open Access Publications.
International Conferences 2014 – 2015
Malaysia Conferences, Thailand Conferences, Singapore Conferences, Hong Kong Conferences, Dubai Conferences, Turkey Conferences, Conference Listing, Conference Alerts
Prevalence of Rota Virus Detection by Reverse TranscriptasePolymerase Chain R...IOSRJPBS
The present study was conducted for the period from 1/6/2016 to 20/1/2017 in Baquba city. The study aimed to detection of rotavirus in stool specimens of children fewer than five age and also explore the effects of certain demographic factors on the detection rates by revers transcriptase- polymerase chain reaction. The study included 49 patients with acute diarrhea, 32 were male and 17 were female. The age range was two months to 5 years. Demographic information on the patients regarding age, sex, residence, type of feeding and source of drinking water were collected from their parents. Stool specimens were collected from each patients and. Detection of rotavirus in stool specimens was done by conventional reverse transcriptase polymerase chain reaction (RT-PCR). The results of present study showed that the overall infection rate by rotavirus among patients with acute diarrhea by RT-PCR tests was 93.88%. The highest infection rate was recorded among those >10-≤15 months of age. None of the results showed significantly difference between female and male, PCR (88% vs 96.87%). Likewise, there was insignificantly difference between urban and rural residence, PCR (95.65% vs 92.30%). The results revealed insignificantly higher infection rate among patients (those below 2 years) feed mixing (91.66%) and bottled (100%) compared to that breast feeding (77.77%) by RT-PCR. The rotavirus infection rate was insignificantly higher among patients consuming municipal water for drinking (97.22%) compared to those consuming bottled water (84.61%) by the RT-PCR. The study concluded that rotavirus was detected in high rates among children less than 5 years old with acute diarrhea in Baquba city, particularly those less than 2 year old.
Yeasts such as Candida are common causes of bloodstream infections in ICU patients. Candida infections in the ICU have a high mortality rate of 15-25% and are the 4th most common cause of hospital-acquired bloodstream infections. Diagnosis can be challenging due to low sensitivity of blood cultures, but newer tests such as PCR, antigen detection assays, and MALDI-TOF mass spectrometry provide more rapid detection of Candida compared to standard culture methods. The presence of risk factors such as abdominal surgery, central venous catheters, antibiotics use, and prolonged ICU stay increase the risk of developing Candida bloodstream infections in critically ill patients.
This document provides an outline for a presentation on HCV genotyping methods. It discusses the morphology and characteristics of HCV, its history and structure. It describes the six genotypes of HCV and their geographical distribution. It also discusses mutants of HCV, clinical importance of genotypes, laboratory diagnosis, and different methods for genotyping including direct sequencing, RFLP typing of the 5'UTR, and line probe assay (LiPA). The advantages of LiPA include it being easy, less time consuming and capable of reliably genotyping HCV RNA directly from clinical samples.
Molecular biomarkers can be used for several purposes in infectious disease research and clinical practice. These include detecting pathogens, measuring antibody responses, identifying markers of virulence, resistance, and disease severity, and understanding human immune responses and genetic susceptibility. Challenges include lack of sensitivity, mobile genetic elements, and changes in RNA sequences. Whole genome sequencing allows investigation of microbial phylogeny, evolution, and virulence factors.
This document discusses various laboratory diagnostic techniques for parasitic infections. It begins by noting that light microscopy remains the standard for diagnosis of most parasites, but nucleic acid tests are becoming more popular. Immunological diagnosis using techniques like ELISA and rapid diagnostic tests (RDTs) have advantages like speed and ease of use. The document then examines specific techniques for diagnosing various parasites like malaria, cryptosporidiosis, amoebiasis, trichomoniasis, lymphatic filariasis, and leishmaniasis. It discusses advantages and limitations of different antigen and antibody detection methods.
Novel research aimed at finding a cure for AIDS requires animal models responding to human antiretroviral drugs. However, there have been few antiretrovirals cross-active against the simian viruses. In this study, we expanded the arsenal of drugs active against the simian retrovirus SIVmac251 and showed that this virus is inhibited by the protease inhibitor, darunavir, and the CCR5 blocker, maraviroc. Administration of these two drugs in combination with the reverse transcriptase inhibitors, tenofovir and emtricitabine, and the integrase inhibitor, raltegravir, resulted in prolonged plasma viral loads below assay detection limits, and, surprisingly, restricted the viral reservoir, a marker of which is viral DNA. We then decided to employ this multidrug regimen (termed “highly intensified ART”) in order to increase the potency of a previous strategy based on the gold drug auranofin, which recently proved able to restrict the viral reservoir in vivo. A short course of highly intensified ART following the previous treatment resulted, upon therapy suspension, in a remarkably spontaneous control of the infection, that may pave the way to a persistent suppression of viremia in the absence of ART. These results corroborate the robustness of the macaque AIDS model as a vanguard for potentially future treatments for HIV in humans.
A single-reaction quadruplex qPCR assay was developed that can rapidly detect and differentiate Burkholderia mallei and Burkholderia pseudomallei. The assay uses three signature sequences - a multicopy transposase sequence common to both species for sensitive detection, and two unique sequences for species differentiation. It also incorporates an internal control for DNA extraction and amplification using Bacillus thuringiensis. The assay enables detection of less than 1 genome equivalent and differentiation of B. mallei and B. pseudomallei with high sensitivity and reliability for diagnostic and surveillance purposes.
This study compared microscopy and PCR techniques for diagnosing malaria in suspected patients in Nepal. Of 824 suspected malaria cases tested, 19.2% were confirmed by microscopy, with most being P. vivax (10.9%) or P. falciparum (7.7%) infections. PCR testing of 132 blood samples detected more cases than microscopy, including some microscopy-negative samples. PCR was better able to detect mixed infections and identified some samples to the species level that microscopy identified only as Plasmodium. While PCR is more sensitive for detection and useful for research, microscopy remains the standard for routine diagnosis due to its lower cost and feasibility.
Presentation 2.1 Update June 2016 on AHPND and EHP research in Thailand (Dr T...ExternalEvents
http://www.fao.org/documents/card/en/c/28b6bd62-5433-4fad-b5a1-8ac61eb671b1/
FAO Second International Technical Seminar/Workshop on Acute hepatopancreatic necrosis disease (AHPND) There is a way forward! FAO Technical Cooperation Programme: TCP/INT/3501 and TCP/INT/3502.
Plasma levels of circulating nucleic acids (CNAs) were significantly higher in patients with Plasmodium vivax malaria compared to healthy donors. CNAs levels strongly correlated with clinical markers of malaria morbidity, including fever and thrombocytopenia. Higher CNAs levels were also associated with a more severe clinical presentation based on a scoring system. These findings suggest that CNAs have potential as sensitive biomarkers for assessing severity of P. vivax malaria infections.
The document summarizes preliminary research toward developing a method for stably transfecting the malaria parasite Plasmodium vivax. The researchers tested various transfection conditions and found the highest parasite survival rates using the Amaxa Nucleofector program U-033 and pre-loading erythrocytes with DNA. However, no fluorescent parasites were observed, likely due to the low efficiency of Plasmodium transfection. Future work aims to increase parasite numbers for transfection and further optimize methods.
Dr. Kurt Stevenson - Antimicrobial Resistance Surveillance and Management in ...John Blue
Antimicrobial Resistance Surveillance and Management in Hospital and Community Settings - Issues for Human Population Medicine - Dr. Kurt Stevenson, The Ohio State University Medical Center, from the 2012 NIAA One Health Approach to Antimicrobial Resistance and Use Symposium, October 26-27, 2012, Columbus, OH, USA.
More presentations at:
http://www.trufflemedia.com/agmedia/conference/2012-one-health-to-approach-antimicrobial-resistance-and-use
This study evaluated the use of quantitative PCR (qPCR) to genotype single nucleotide polymorphisms (SNPs) near a mutation in the RTEL1 gene for preimplantation genetic diagnosis of Dyskeratosis Congenita, compared to the standard method using short tandem repeats (STRs). The standard STR method misdiagnosed 3 of 14 embryos due to recombination between the distant STR marker and mutation. In contrast, qPCR of closely linked SNPs identified recombination in 9 of 17 embryos and correctly diagnosed all embryos. This case demonstrates that qPCR of SNPs provides improved sensitivity over STRs for detecting recombination near telomeric mutations.
Can Meropenem Heteroresistance in OXA-48-Producing K. pneumoniae be Inferred...PROANTIBIOTICOS
This document discusses the phenomenon of heteroresistance in bacteria and analyzes whether it occurs in OXA-48 producing Klebsiella pneumoniae. It finds that population analysis profile curves did not show evidence of heteroresistance in various clones of OXA-48 K. pneumoniae, as cells growing at high carbapenem concentrations were resistant mutants rather than a heteroresistant subpopulation. The presence of colonies growing in the inhibition zone of meropenem E-tests was also not indicative of heteroresistance in this case. In conclusion, heteroresistance was not observed in OXA-48 producing K. pneumoniae.
The study examines the spatial patterns of malaria among the Bharia tribe in Tamia, Chhindwara district of Madhya Pradesh, India. Tamia has over 85% Bharia tribal population and is surrounded by forests and hills providing favorable conditions for malaria. Malaria is caused by four plasmodium parasites transmitted via Anopheles mosquitoes. The most common types in the area are Plasmodium falciparum and Plasmodium vivax.
Secondary data on malaria cases from 2006-2010 was collected from local health centers and analyzed by species, gender, and age. Results show that total malaria cases increased five-fold from 2006 to 2010 likely due to drug resistance. P. fal
The document discusses the determination of diffusion constants in boronated powder metallurgy samples of the iron-carbon-copper system. Experiments were conducted on powdered samples with 0.1% carbon and 1-3% copper. The thickness of the boride layers formed after boronation at temperatures of 920-980°C were measured. The data was used to calculate the activation energy (Q) and pre-exponential factor (Do) based on parabolic growth curves. The results show that Q increases with sample density from 5.8 to 7 g/cm3. Adding up to 2% copper reduces Q values, but higher copper concentrations increase Q similar to pure iron samples.
This study aimed to investigate the presence of arboviruses like dengue virus in clinical samples from 111 malaria patients in the Amazon region of Brazil.
Dengue virus serotype 2 was detected in two patients from Novo Repartimento, Pará who also had active Plasmodium vivax malaria infections. Despite limited data, concurrent dengue and malaria infections are likely more common in the Amazon region than detected, as both diseases co-circulate and have similar transmission vectors and clinical presentations, making dual diagnosis possible. Further research is needed to better understand the frequency of co-infection in this region.
1. The study characterized antibody responses to Plasmodium falciparum invasion ligands EBA-140 and EBA-181 in individuals from malaria-endemic areas of Brazil and Cameroon.
2. Responses differed between populations, with African individuals strongly reacting to most EBA fragments while Brazilian individuals from Mato Grosso reacted weakly and those from the Amazon had elevated but lower responses than Africans.
3. When compared to responses against other malaria proteins, the Brazilian population appeared to have more variable ability to recognize P. falciparum invasion ligands, distinct from the African population.
This document analyzes the frequency of two polymorphisms (C282Y and H63D) in the HFE gene in malaria patients and blood donors from four states in the Brazilian Amazon region. The study found:
1) No individuals were homozygous for the C282Y polymorphism, and only 5 heterozygous individuals were detected, all from Pará State.
2) The most common genotype for the H63D polymorphism was heterozygous in both patient groups.
3) Allele frequencies for the H63D polymorphism were higher than for the C282Y polymorphism, consistent with other studies on Brazilian populations.
This document discusses techniques to reduce leakage current and power consumption in static random-access memory (SRAM) cells implemented using independent gate fin field-effect transistors (FinFETs). It first describes the independent gate FinFET SRAM cell design and its advantages over other designs. It then examines two circuit-level leakage reduction techniques: 1) using multi-threshold voltages by connecting high-threshold transistors to reduce leakage when in standby mode, and 2) adding a gated power supply transistor to reduce leakage through stacking effects. Simulation results show that both techniques can reduce leakage current and power in the independent gate FinFET SRAM cell, with multi-threshold voltages providing better leakage control.
This document presents a method for summarizing user interface event logs through a set of visual signs based on Peirce's theory of semiotics. An experiment was conducted with 28 participants to evaluate signs representing common UI events like click, mouseover, and submit. The results showed interpretation accuracy improved from 40% to 61.5% after refining the signs based on feedback. The document concludes the proposed signs can help designers visualize usage data and may be reused in other applications.
Two main animal pathogenic subspecies of Mycobacterium avium are M. avium avium (Maa) and M. avium paratuberculosis (Map). Their pathogenicity is host-specifi c, Maa causing avian tuberculosis in poultry whereas Map commonly cross-infects to ruminant.Veterinary diagnosis of M. avium infections is microscopic examination of acid-fast bacilli or culture in Löwenstein-Jensen medium,which are time-consuming and low sensitivity. This present study aimed to apply real-time PCR coupled with High-Resolution Melting (HRM) analysis for differential detection of Maa in Thai domestic ducks. Specifi c primer targeting host-expression dependent (hed) region
was designed, PCR product of Maa were amplifi ed from duck’s tissue lesions whereas Map were amplifi ed from cow and deer. HRM real-time PCR was performed and analyzed. Different HRM patterns were showed and melting temperature were analyzed at 83.26 ± 0.12°C for Maa and 84.04 ± 0.09°C for Map. This technique can detect as few as 102 DNA copies and present high specifi city by negative amplifi cation of other pathogenic bacterial species. This technique is sensitive, specifi c, rapid and does not require fl uorescent probes or post-PCR electrophoresis. Our technique is a possible new tool for the detection of Maa and Map infection in tissue specimens.
Two main animal pathogenic subspecies of Mycobacterium avium are M. avium avium (Maa) and M. avium paratuberculosis (Map). Their pathogenicity is host-specific, Maa causing avian tuberculosis in poultry whereas Map commonly cross-infects to ruminant. Veterinary diagnosis of M. avium infections is microscopic examination of acid-fast bacilli or culture in Löwenstein-Jensen medium,which are time-consuming and low sensitivity. This present study aimed to apply real-time PCR coupled with High-Resolution Melting (HRM) analysis for differential detection of Maa in Thai domestic ducks. Specific primer targeting host-expression dependent (hed) region
was designed, PCR product of Maa were amplified from duck’s tissue lesions whereas Map were amplified from cow and deer. HRM real-time PCR was performed and analyzed. Different HRM patterns were showed and melting temperature were analyzed at 83.26 ± 0.12°C for Maa and 84.04 ± 0.09°C for Map. This technique can detect as few as 102 DNA copies and present high specifi city by negative amplification of other pathogenic bacterial species. This technique is sensitive, specific, rapid and does not require fluorescent probes or
post-PCR electrophoresis. Our technique is a possible new tool for the detection of Maa and Map infection in tissue specimens.
- A study of malaria infections in western Thailand found that 90.2% of Plasmodium infections were asymptomatic and submicroscopic, detected through molecular and serological methods but not microscopy. Mixed-species infections made up 68% of positive cases among febrile patients, all of which were misdiagnosed. Antibody levels against Plasmodium increased seasonally and with age. Asymptomatic carriers had weaker antibody responses than febrile patients. Despite reduced transmission, undetected submicroscopic infections pose a challenge to malaria elimination in the region.
This document describes the development of a PCR-RFLP assay to identify Plasmodium species and variants of P. vivax infecting Anopheles mosquitoes. Specific primers were designed that target regions of the circumsporozoite gene to distinguish P. falciparum, P. malariae, and P. vivax variants VK210, VK247, and P. vivax-like. The assay was tested on artificially infected mosquitoes and showed good agreement with nested PCR. The PCR-RFLP method provides a sensitive way to detect Plasmodium species and variants, which can help understand malaria transmission dynamics.
Association of leucocytosis and hemozoin pigment in leucocytes with disease s...iosrjce
IOSR Journal of Dental and Medical Sciences is one of the speciality Journal in Dental Science and Medical Science published by International Organization of Scientific Research (IOSR). The Journal publishes papers of the highest scientific merit and widest possible scope work in all areas related to medical and dental science. The Journal welcome review articles, leading medical and clinical research articles, technical notes, case reports and others.
This document summarizes information about malaria vaccines. It discusses how malaria is caused by Plasmodium parasites and transmitted by mosquitoes. Four species can infect humans. Current vaccines target different stages of the parasite's life cycle, including pre-erythrocytic, blood, and sexual stages. Challenges to vaccine development include the parasite's ability to evade the immune system through antigenic variation. Several candidate vaccines are discussed that target different stages, but none have achieved high levels of efficacy and durability.
Chloroquine resistant malaria,vaccines for malariaJonaid Ali
This document summarizes information about chloroquine resistant malaria and vaccines for malaria. It discusses the history and life cycle of the malaria parasite, mechanisms of drug resistance, treatment approaches including chloroquine and new drug combinations, and the development of vaccine candidates like RTS,S that target different stages of the parasite's life cycle. Key points covered include how chloroquine resistance first emerged and spread, the use of artemisinin combination therapies to address resistance, and clinical trials underway to evaluate vaccine candidates aimed at prevention, transmission blocking, and reducing disease severity.
This study evaluated the distribution of Plasmodium vivax variants (VK210, VK247, and P. vivax-like) in three areas of Brazil using a new GFM-PCR-ELISA technique. All variants were found in all three areas. VK210 was most commonly found as a single infection while the others occurred in mixed infections. VK210 was associated with the highest parasitemia levels while P. vivax-like had the lowest. Parasitemia clearance times did not differ based on variant or treatment schedule. The new technique was accurate for epidemiological surveys of the vivax complex.
This document discusses various methods for diagnosing malaria, including clinical diagnosis, microscopy, rapid diagnostic tests (RDTs), serological tests, polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), microarrays, and flow cytometry (FCM). Microscopy remains the gold standard but requires expertise and specialized equipment. RDTs provide rapid results using minimal equipment but cannot quantify parasites. Molecular methods like PCR and LAMP can detect low parasite levels but require specialized labs. Different methods have varying detection limits, time requirements, expertise needed, and costs. The optimal method depends on the situation and resources available.
This document discusses malaria and efforts to develop an effective malaria vaccine. It defines malaria as a protozoan disease caused by Plasmodium parasites and transmitted through mosquito bites. Four Plasmodium species can cause malaria in humans. The document outlines the complex lifecycle of the malaria parasite and describes current vaccine approaches that target different stages of the lifecycle. It provides details on the RTS,S/AS01 vaccine, the most advanced candidate to date, and clinical trials that found it provided partial protection. Developing an effective vaccine faces challenges but remains an important goal for malaria control and elimination efforts.
Malaria due to Plasmodium falciparum is a major public health concern in Cameroon and Africa, responsible for high rates of morbidity and mortality. While control measures have been effective, an effective vaccine is needed to achieve global malaria elimination goals. This study analyzed genetic diversity in the merozoite surface protein 1 (msp1) gene of P. falciparum isolates from Mount Cameroon. It found 45 distinct DNA fragments in samples from 81 of 173 infected individuals, indicating significant intragenic recombination contributing to parasite diversity. Understanding this diversity is important for vaccine development against P. falciparum.
To Present an up-to-date summary of the best microbiology practice related to malaria diagnostics
PGY-3, IAU Clinical Microbiology Residency
Dammam, KSA
1. The authors developed a quantitative real-time PCR (Q-PCR) method for detecting Rhodococcus equi, an important horse and emerging human pathogen.
2. The method uses two Q-PCR assays, one targeting the chromosomal choE gene to quantify total R. equi, and the other targeting the virulence plasmid gene vapA to detect the "horse-pathogenic" genotype.
3. Testing on 178 R. equi isolates and 77 non-target bacteria showed the assays were 100% sensitive and specific. The method can accurately quantify R. equi down to 1,000 CFU/ml in bronchoalveolar lavage fluid.
This research article characterized the genetic diversity of Plasmodium vivax and P. falciparum populations from pregnant women in four malaria-endemic countries. Between 2008-2011, nearly 2000 pregnant women were recruited from Brazil, Colombia, India, and Papua New Guinea and followed until delivery, collecting blood samples. Seven P. vivax microsatellite markers were used to genotype 229 P. vivax isolates. P. vivax populations showed moderate to high genetic differentiation between countries and higher diversity than P. falciparum populations from the same areas. Diversity of P. vivax was very high in some settings compared to transmission levels, suggesting stable demographic histories.
This document discusses malaria diagnosis approaches. It notes that while efforts have reduced malaria mortality and morbidity, it remains a major disease burden in sub-Saharan Africa. Current diagnostic methods like microscopy and rapid diagnostic tests (RDTs) are useful but have limitations. More advanced tools are not suitable for field use. There is a need for new diagnostic approaches tailored to conditions in endemic regions, leveraging untapped materials like urine. Novel tools in development promise improved diagnosis if successful.
We present evidence of Plasmodium vivax infection in two homozygous FY*B-33 (Duffy-negative) individuals from the Brazilian Amazon region. Molecular analysis confirmed P. vivax infection through detection of P. vivax small subunit rRNA and circumsporozoite protein genes. One individual had a mixed infection of VK210 and P. vivax-like genotypes, while the other was infected with VK210. Both individuals also had antibodies to the P. vivax merozoite surface protein 1. This provides rare evidence that P. vivax may be capable of invading Duffy-negative red blood cells in some regions, though additional studies are needed to better understand this finding.
This study aimed to better understand the current epidemiology of malaria in western Thailand using more sensitive molecular detection methods. The study analyzed blood samples from 219 residents of a village and 61 patients at a malaria clinic. Quantitative PCR (qPCR) detected Plasmodium DNA in 25 village samples (11.4% prevalence), mostly asymptomatic and submicroscopic infections. qPCR also found 27 positive samples (44.3% prevalence) from the clinic, including submicroscopic infections. All samples showed antibody responses to malaria antigens, suggesting widespread exposure despite low detected parasite levels by microscopy. These findings suggest parasite prevalence is higher than estimated by local authorities and that asymptomatic and submicroscopic infections still contribute to transmission as malaria declines in Thailand.
This study evaluated antibody responses to the Pv200L fragment of Plasmodium vivax merozoite surface protein-1 (PvMSP-1) in individuals from 4 malaria-endemic regions in Brazil. Plasma samples from 261 P. vivax infected individuals were tested for antibodies to Pv200L by ELISA. The frequency of antibody responders ranged from 71.9-98.7% between regions and correlated with malaria transmission intensity. Higher antibody levels were also associated with greater past exposure to malaria parasites. Results provide evidence that Pv200L elicits naturally acquired antibodies and could be a potential vaccine candidate.
The document evaluates the usefulness of rapid diagnostic tests (RDTs) for diagnosing malaria compared to microscopic examination. It finds that RDTs diagnosed 41 out of 43 total malaria cases in the study, while microscopy only diagnosed 34 cases. RDTs were found to be highly sensitive (96.55%) and specific (71.79%) for detecting Plasmodium falciparum malaria compared to microscopy. The study concludes that RDTs are an effective, rapid and accurate method for diagnosing malaria, especially in cases where immediate diagnosis is needed. RDTs performed better than microscopy and using both tests together provides the best approach for malaria diagnosis.
1. A study analyzed genetic and immune response differences between P. vivax circumsporozoite (CS) genotypes VK210 and P. vivax-like.
2. Phylogenetic analysis of 18S rRNA and CytB genes found high similarity between the genotypes, with zero nucleotide diversity, placing them in the same clade.
3. Individuals infected with P. vivax-like had a lower antibody response against CS repetitive region peptides than those with VK210, suggesting variation is limited to the CS repetitive region.
Similar to 2003 malária e diagnóstico sorológico msp119 (20)
This study investigated the relationship between variants of the glycophorin B (GPB) gene and susceptibility to Plasmodium falciparum infection in the Brazilian Amazon. The researchers found that individuals carrying the GYPB*S allele were more likely to be infected with P. falciparum than those without this allele. Additionally, population genetics analysis suggested that natural selection has shaped patterns of genetic diversity at the GYPB locus. This study provides evidence that genetic variation in GPB influences susceptibility to P. falciparum infection in this population.
This document summarizes a study that investigated the influence of HLA-DRB1 alleles on the production of antibodies against malaria antigens in individuals naturally infected with Plasmodium vivax in Brazil. The study found an association between HLA-DR3 and HLA-DR5 alleles and lack of antibody response to the amino terminal region of the circumsporozoite protein (CSP). It also found an association between HLA-DR3 and higher antibody response to merozoite surface protein 1 (MSP1). No significant associations were found between HLA-DRB1 alleles and antibody responses to other malaria antigens tested.
1. Researchers studied Plasmodium falciparum field isolates from Colombia, Peru, and Brazil to determine the invasion pathways and ligand polymorphisms used.
2. They found that most isolates from Colombia and Peru invade red blood cells through an atypical pathway that is resistant to all enzyme treatments, unlike known pathways.
3. This unusual pathway was associated with specific variants of PfRh2a, PfRh5, and EBA-181 ligands, suggesting these proteins play a major role in this pathway. The study demonstrates diversity in invasion mechanisms between regions.
This study examined 51 Brazilian Plasmodium falciparum isolates for polymorphisms in the Pfmdr1 gene thought to be associated with chloroquine resistance. 49 of the isolates were found to be resistant to chloroquine in vitro, while all were sensitive to mefloquine, amodiaquine, and quinine. The isolates were analyzed for three Pfmdr1 polymorphisms: Asn86Tyr, Asn1042Asp, and Asp1246Tyr. Asn86Tyr was not detected in any isolates, while Asn1042Asp was found in 50 isolates and Asp1246Tyr was found in all 51 isolates. This provides support that As
This document analyzes genetic variation at the Pfs48/45 gene and microsatellite loci in 255 Plasmodium falciparum isolates from 5 populations. It finds:
1) Alleles and haplotypes of 5 SNPs in the Pfs48/45 gene varied extremely between populations, much more so than alleles at 11 neutral microsatellite loci.
2) Measurements of between-population allele frequency variation (FST) were 4-7 times higher for Pfs48/45 than microsatellites, both within and between continents.
3) The highly skewed Pfs48/45 patterns suggest divergent selection on the protein's amino acid sequence between populations, indicating it may determine game
This study compared ELISA and PCR-ELISA techniques for detecting human Plasmodium parasites in Anopheles mosquitoes from the Amazon region of Brazil. The PCR-ELISA technique confirmed all positive and negative ELISA results but detected additional Plasmodium species in 5 of the 32 positive mosquitoes that were not detected by ELISA alone. The PCR-ELISA is more sensitive than ELISA for detecting human malaria parasites in mosquitoes.
1) O documento analisa os casos de malária no estado de Santa Catarina entre 1996-2001, com 5,5% das 4.707 amostras sendo positivas.
2) Plasmodium vivax causou 69% dos casos, Plasmodium falciparum 25,6%, infecções mistas 5% e Plasmodium malariae 0,4%.
3) 67,4% dos casos foram importados e 32,6% autóctones, com aumento de casos importados nos anos subsequentes.
This study analyzed genetic diversity and population structure of Plasmodium falciparum in 5 populations in the Brazilian Amazon region. Microsatellite markers were analyzed in 196 parasite isolates. There was significant multilocus linkage disequificance within populations, particularly those with fewer mixed infections. However, most isolates had unique multilocus genotypes, indicating genetic diversity. Genetic divergence between populations was substantial but did not correlate simply with geographical distance. The findings suggest distinct population structures and minimal gene flow between foci in the region.
This study investigated genetic mutations associated with chloroquine resistance in Plasmodium falciparum samples from the Brazilian Amazon region. The study analyzed 40 samples from 4 localities for mutations in the pfmdr1, cg2, and pfcrt genes. It found 100% of samples contained mutations in pfmdr1 codons 184, 1042, and the cg2 gamma region associated with chloroquine resistance. Most samples also contained the pfcrt K76T mutation, except some from Porto Velho which matched a Thai resistant genotype. This research contributes to understanding the molecular basis of widespread chloroquine resistance in this region.
1. The study developed a new PCR/RFLP technique to identify the 3 genotypes of Plasmodium vivax circumsporozoite protein (VK210, VK247, and P. vivax-like) using DNA extracted from blood samples.
2. The technique uses PCR amplification of the central immunodominant region of the CSP gene followed by restriction enzyme digestion and fragment analysis to distinguish the genotypes.
3. Testing demonstrated the technique could accurately identify the genotypes using plasmid controls for each variant, and that it had high sensitivity detecting parasitemia levels as low as 0.0069 parasites per microliter.
Mixed Plasmodium falciparum infections were common in four areas of the Brazilian Amazon region. Molecular diagnosis found 73% of infections were single P. falciparum infections, while 27% were mixed infections, mostly double infections. Mixed infections were associated with weaker clinical malaria symptoms like lower rates of fever and headache compared to single P. falciparum infections. The study highlights the need for improved malaria diagnosis to better understand mixed infections and their impact on disease severity.
This study investigated the frequencies of ABO blood group genotypes and alleles in Plasmodium falciparum malaria patients and blood donors from the Brazilian Amazon region. The researchers found that over half of individuals had the ABO*O01O01 genotype. The ABO*AO01 genotype was the second most common. No significant differences were detected in genotype or allele frequencies between the malaria patients and blood donors. Analysis of O alleles found the O1 variant allele to be most frequent in both groups, with no evidence of the homozygous O2 allele.
This study investigated the relationship between variants of the glycophorin B (GPB) gene and susceptibility to Plasmodium falciparum infection in the Brazilian Amazon. The researchers found that individuals carrying the GYPB*S allele were more likely to be infected with P. falciparum than those without this allele. Sequence analysis of GYPB also suggested it has been under natural selection due to malaria. This study provides evidence that genetic variation in GPB receptor influences the ability of P. falciparum to invade red blood cells in this population.
This document summarizes a study that investigated the influence of HLA-DRB1 alleles on the production of antibodies against malaria antigens in individuals naturally infected with Plasmodium vivax in Brazil. The study found an association between HLA-DR3 and HLA-DR5 alleles and lack of antibody response to the amino terminal region of the circumsporozoite protein (CSP). It also found an association between HLA-DR3 and higher antibody response to merozoite surface protein 1 (MSP1). No significant associations were found between HLA-DRB1 alleles and antibody responses to other malaria antigens tested.
1) Field isolates of Plasmodium falciparum from Colombia and Peru were found to invade red blood cells through an atypical pathway that was resistant to all enzyme treatments, unlike what is typically seen.
2) The invasion pathways and ligand polymorphisms differed between Colombian, Peruvian, and Brazilian isolates, with Peruvian isolates showing a combination of Colombian and Brazilian characteristics.
3) The atypical resistant pathway was associated with specific variants of PfRh2a, PfRh5 and EBA-181, which may be major players in this pathway based on expression levels.
More from Faculdade de Medicina de Sao Jose do rio Preto (15)
Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
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.
The skin is the largest organ and its health plays a vital role among the other sense organs. The skin concerns like acne breakout, psoriasis, or anything similar along the lines, finding a qualified and experienced dermatologist becomes paramount.
These lecture slides, by Dr Sidra Arshad, offer a simplified look into the mechanisms involved in the regulation of respiration:
Learning objectives:
1. Describe the organisation of respiratory center
2. Describe the nervous control of inspiration and respiratory rhythm
3. Describe the functions of the dorsal and respiratory groups of neurons
4. Describe the influences of the Pneumotaxic and Apneustic centers
5. Explain the role of Hering-Breur inflation reflex in regulation of inspiration
6. Explain the role of central chemoreceptors in regulation of respiration
7. Explain the role of peripheral chemoreceptors in regulation of respiration
8. Explain the regulation of respiration during exercise
9. Integrate the respiratory regulatory mechanisms
10. Describe the Cheyne-Stokes breathing
Study Resources:
1. Chapter 42, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 36, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 13, Human Physiology by Lauralee Sherwood, 9th edition
Mercurius is named after the roman god mercurius, the god of trade and science. The planet mercurius is named after the same god. Mercurius is sometimes called hydrargyrum, means ‘watery silver’. Its shine and colour are very similar to silver, but mercury is a fluid at room temperatures. The name quick silver is a translation of hydrargyrum, where the word quick describes its tendency to scatter away in all directions.
The droplets have a tendency to conglomerate to one big mass, but on being shaken they fall apart into countless little droplets again. It is used to ignite explosives, like mercury fulminate, the explosive character is one of its general themes.
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
Does Over-Masturbation Contribute to Chronic Prostatitis.pptxwalterHu5
In some case, your chronic prostatitis may be related to over-masturbation. Generally, natural medicine Diuretic and Anti-inflammatory Pill can help mee get a cure.
Travel vaccination in Manchester offers comprehensive immunization services for individuals planning international trips. Expert healthcare providers administer vaccines tailored to your destination, ensuring you stay protected against various diseases. Conveniently located clinics and flexible appointment options make it easy to get the necessary shots before your journey. Stay healthy and travel with confidence by getting vaccinated in Manchester. Visit us: www.nxhealthcare.co.uk
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotesPsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
10 Benefits an EPCR Software should Bring to EMS Organizations Traumasoft LLC
The benefits of an ePCR solution should extend to the whole EMS organization, not just certain groups of people or certain departments. It should provide more than just a form for entering and a database for storing information. It should also include a workflow of how information is communicated, used and stored across the entire organization.
2. Malaria Journal 2003, 2 http://www.malariajournal.com/content/2/1/39
Background different regions of the world that does not restrict recog-
Plasmodium vivax accounts worldwide for an estimated nition by human antibodies [10,11]. Together, these
70–80 million cases of malaria per year [1]. In some coun- results suggested that it could be possible to develop an
tries such as Brazil, P. vivax was responsible for approxi- ELISA using a single recombinant protein based on the P.
mately 79% of the 389,736 cases of the disease reported vivax MSP119. This relatively simple and inexpensive tech-
in 2001 [2]. nique could be of great applicability for epidemiological
studies, the screening of blood donors and the serological
Laboratory methods are important tools for the control of diagnosis of malaria caused by P. vivax.
the disease progress. They can be useful for the individual
diagnosis or for the patients' follow-up after specific anti- In the present study three purified recombinant proteins
malaria treatment. Conventional light microscopy has produced in E. coli (GST-MSP119, His6-MSP119 and His6-
been widely used for malaria diagnosis. However, outside MSP119-PADRE) and one in Pichia pastoris (yMSP119-
areas where malaria is endemic, it is rarely performed. PADRE) were compared for their ability to be recognized
Also, this method is time consuming and requires trained by IgG antibodies of individuals with patent P. vivax infec-
personnel. tion. Serological evaluation was performed with serum
samples collected from individuals living in areas
In attempts to overcome these problems several rapid endemic for malaria in the north of Brazil and compared
diagnostic tests have been developed recently. These tests to serum samples from individuals never exposed to P.
detect specific proteins such as HRP2, a histidine rich pro- vivax malaria.
tein 2, or pLDH, lactate dehydrogenase, in unfractionated
blood of patients with malaria. However, these assay do Materials and methods
not differentiate P. vivax from Plasmodium malariae or Plas- Study population
modium ovale infections, and vary in their sensitivity and Sera from 430 individuals were used in this study, of
specificity (reviewed in reference [3]). which 200 were from patients with patent P. vivax malaria
and 230 from persons not exposed to P. vivax malaria
Molecular diagnosis by PCR is described as the most sen- (negative controls). The blood samples from P. vivax
sitive and specific method for Plasmodium detection. patients were collected in the state of Pará, in the north of
Genus- and species-specific primers have been used to Brazil, in areas endemic for malaria: 103 from Belém, 21
amplify Plasmodium ssrRNA genes of the four human from Marabá, 20 from Itaituba, 20 from Tailândia, 36
malaria parasites and to detect mixed infections [4-6]. from Igarapé-Açu. Patent infection was documented by
However, this methodology is costly and requires trained microscopic analysis of Giemsa-stained blood drops.
personnel for its implementation. These samples were obtained between January 1996 and
July 1999 with informed consent of all individuals and
Detection of antibodies by immunofluorescence or ELISA kept at -20°C.
has been used for seroepidemiology of malaria. However,
in the case of P. vivax, the difficulty of blood stage cultiva- The 230 individuals non-exposed to P. vivax malaria
tion has been hindering the use of these methodologies. included: (i) 49 donors to blood banks in the city of São
Production of recombinant proteins through the tech- Paulo, an area where malaria is not endemic (negative
niques of genetic engineering may provide sufficient P. controls); (ii) 108 blood bank donors with unrelated
vivax blood stage antigen(s) for the establishment of spe- infectious diseases, detected serologically; among them
cific serological assays. 21 with Chagas Disease, 21 with syphilis, 19 with HBV, 21
with HCV, 14 with HTLV and 12 with HIV; (iii) 10 indi-
In the course of immuno-epidemiological studies using viduals positive for antinuclear antibodies (ANA) and 10
recombinant proteins based on the sequence of the Mero- for rheumatoid factors (RF); (iv) 53 individuals living in
zoite Surface protein-1 (MSP1) of P. vivax, we found that distinct areas in West Africa where malaria caused by Plas-
a recombinant protein representing the 19 kDa region of modium falciparum is endemic: a) 26 adults without clear
MSP1 (MSP119) was highly immunogenic during natural symptoms of malaria or other infectious disease from Sen-
infection in humans [7,8]. This recombinant protein was egal (n = 19) and Gambia (n = 7), b) seven children from
recognized by antibodies of a large fraction of Brazilian Gambia during patent infection by P. falciparum, c) 20
individuals recently exposed to P. vivax [7]. This observa- malaria immune adults from Ghana. Aliquots of these
tion was subsequently confirmed in studies performed in samples were kindly supplied by Dr. Marcelo Urbano Fer-
Korea, where more than 90% of P. vivax-infected individ- reira (Universidade de São Paulo, São Paulo) and Dr. Sil-
uals displayed specific antibodies to P. vivax MSP119 [9]. via Di Santi (Superitendência de Controle de Endemias,
Also important was the observation that the P. vivax SUCEN, São Paulo). Clinical and laboratory data were
MSP119 gene displays very limited allele polymorphism in reported elsewhere [12-14].
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Table 1: Recombinant proteins based on the MSP119 of P. vivax.
Recombinant protein Vector Microorganism Molecular Weight (kDa) Ref.
GST-MSP119 pGEX-3X E. coli 36 15
His6-MSP119 pET-14b E. coli 18 15
His6-MSP119-PADRE* pET-14b E. coli 18 15
yMSP119-PADRE* pPIC-9K Pichia pastoris 18 16
* PADRE epitope is composed of amino acids AKFVAAWTLKAAA.
Recombinant proteins sera from 49 blood donors plus five standard deviations
The recombinant proteins used in the present study repre- (SD). The values for sensitivity and specificity were esti-
sent amino acids 1616–1704 of the MSP-1 (Belem strain) mated as described [18] with microscopy used as the gold
of P. vivax. These proteins were expressed in E. coli (GST- standard. The Kruskal-Wallis test was used to test the sig-
MSP119, His6-MSP119 and His6-MSP119-PADRE, ref. 15) nificance of differences between the group values. Differ-
or Pichia pastoris (yMSP119-PADRE, ref. 16). The genera- ences between proportions were analyzed by a Chi-square
tion of the plasmids and expression/purification of the test.
recombinant proteins produced in E. coli or Pichia pas-
toris were performed as described in references 15 and 16, Results
respectively. Reactivity of recombinant proteins expressed in distinct
vectors with serum samples from individuals with patent P.
ELISA for detection of human antibodies vivax
Human IgG antibodies against MSP119 were detected by Four recombinant proteins obtained as earlier described
ELISA as described [7]. ELISA plates were coated with 200 in references 15 and 16 (Table 1) were used. SDS-PAGE
ng/well of each recombinant protein. The amount of analysis of each recombinant protein revealed a single
recombinant protein gave the same OD492 when we used band of the expected molecular weight after Coomassie
an anti-MSP119 MAb [17]. Fifty µl of each solution were blue [15,16] or Silver staining (data not shown).
added to each of 96 well plates (High binding, Costar).
After overnight incubation at room temperature (rt), the An IgG survey of the serum samples of individuals with
plates were washed with PBS-Tween (0.05%, v/v) and patent P. vivax infection patients showed that the values of
blocked with PBS-milk (5% w/v) for two hours at 37°C. positivity were quite similar with the four recombinant
Serum samples were diluted 1:100 in this same solution antigens employed. Ninety to 93.5% of the 200 serum
and 50 µl of each sample was added to each well in dupli- samples tested were positive for IgG with the recombinant
cate. After incubation for two hours at rt and washes with proteins based on the MSP119.
PBS-Tween, 50 µl a solution containing peroxidase-conju-
gated goat anti-human IgG (Fc specific) diluted 1:10,000 When we compared the OD492 values from serum samples
(Sigma) were added to each well. The enzymatic reaction of P. vivax infected individuals, we observed that values
was developed by the addition of 1 mg/ml of o-phenylen- obtained for the recombinant proteins His6-MSP119 and
ediamine (Sigma) diluted in phosphate-citrate buffer, pH His6-MSP119-PADRE were significantly higher than those
5.0, containing 0.03% (v/v) hydrogen peroxide, and was obtained for GST-MSP119 (Fig. 1, P < 0.01, Kruskal-Wallis
stopped by the addition of 50 µl of 4 N H2SO4. Plates were test). On the other hand, no statistically significant differ-
read at 492 nm (OD492) with an ELISA reader (SLT SPEC- ence was observed among values obtained by the compar-
TRA, SLT Labinstruments, Austria). The individual values ison of the recombinant proteins His6-MSP119, His6-
of OD492 obtained for the recombinant proteins of MSP119-PADRE and yMSP119-PADRE, or GST-MSP119
MSP119 were corrected by subtraction of the individual and yMSP119-PADRE (P > 0.05, Kruskal-Wallis test).
values of OD492 obtained against glutathione S-transferase
(GST). Sera from the few individuals who tested negative towards
all four recombinant proteins were also tested for the rec-
Statistical analysis ognition of recombinant proteins representing the N-ter-
OD492 from different samples were plotted using compu- minal region of P. vivax MSP1, MSP3α (C-terminal) or
ter graphics software (GraphPad Prism, Version 3.0, San MSP3β(N and C-terminal and entire protein, references
Diego, California). Cutoff values of each recombinant 19 and 20). All of them failed to recognize any of the
protein in ELISA were calculated as the mean OD492 of recombinant protein tested (data not shown). However,
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4. Malaria Journal 2003, 2 http://www.malariajournal.com/content/2/1/39
GST-MSP119
3.5
His6 -MSP119
3.0
His6-MSP119-PADRE
2.5
yMSP119-PADRE
OD492
2.0
1.5
1.0
0.5
0.0
Recombinant protein
Distribution of OD492 data for 200 sera from individuals with patent malaria infection caused by P.vivax
Figure 1
Distribution of OD492 data for 200 sera from individuals with patent malaria infection caused by P. vivax. The symbols represent
the reactivity of each serum sample tested in duplicate at 1:100 dilution against the indicated recombinant proteins. The hori-
zontal line inside the drops for each recombinant protein represents the cut-off values (0.127, 0.170, 0.198 and 0.500 for GST-
MSP119, His6-MSP119, His6-MSP119-PADRE and yMSP119-PADRE, respectively).
we detected antibodies IgM anti-MSP119 in 90% (9/10) of individuals with unrelated diseases or healthy individu-
these IgG negative individuals. If we consider the results als. Due to limitations on the volume of each sample
of detection of antibodies IgG and IgM for MSP119, the available, sera from African individuals exposed to P. fal-
sensitivity of the assay was of 99.5%. These 10 individuals ciparum were tested only against recombinant protein
were primo-infected and therefore the presence of IgM but His6-MSP119. For the calculation of the specificity of the
not IgG may reflect a delay in the immunoglobulin class assay using the recombinant protein His6-MSP119 the
switch. results that was obtained did not include sera from Afri-
can individuals. The specificity values determined with
From the 200 individuals that we evaluated, 111 were sera from healthy individuals and sera from individuals
primo-infected. One hundred and one of them had spe- with other infectious diseases, were 98.3% (GST-MSP119),
cific IgG for the recombinant proteins that we tested. Only 97.7% (His6-MSP119and His6-MSP119-PADRE) and 100%
10 were negative for IgG and, as mentioned above, 9 of (yMSP119-PADRE). In figure 2, we compared the OD492
them had specific IgM. values from serum samples of P. vivax infected individu-
als, individuals exposed to P. falciparum and individuals
Evaluation of the specificity of the recombinant proteins with unrelated diseases.
tested with serum samples from individuals exposed to P.
falciparum, from unrelated diseases, or healthy donors Discussion
The specificity of the assay using recombinant P. vivax Due to the difficulties in cultivating blood stages of P.
antigens was examined with 230 serum samples from vivax, serological diagnosis of patent P. vivax malaria can
individuals without previous history of P. vivax malaria, best be accomplished with the use of recombinant pro-
including individuals exposed to P. falciparum malaria, teins. In the present study, we compared for purified
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5. Malaria Journal 2003, 2 http://www.malariajournal.com/content/2/1/39
GST-MSP1 19 His 6-MSP1 19
3.0 3.5
2.5 3.0
2.5
2.0
OD492
OD492
2.0
1.5
1.5
1.0
1.0
0.5 0.5
0.0 0.0
Pv
H RF
y
ha
p
BV
V
V
IV
A
Pf
ha
BV
V
V
IV
A
Pv
Pf
H RF
y
p
lt h
Sy
C
AN
TL
lth
Sy
TL
C
AN
H
C
H
C
H
H
H
ea
H
ea
H
H Study groups Study groups
His 6-MSP1 19 -PADRE yMSP1 19 -PADRE
3.0 3.0
2.5 2.5
2.0 2.0
OD492
OD492
1.5 1.5
1.0 1.0
0.5 0.5
0.0 0.0
Pv
H RF
Pv
H RF
ha
p
BV
V
V
IV
A
ha
p
BV
V
V
IV
A
Pf
y
Pf
y
lt h
lt h
Sy
Sy
C
AN
C
AN
TL
TL
H
H
C
C
H
H
H
H
ea
ea
H
H
Study groups Study groups
Figure 2 of the OD492 data for sera from individuals with patent P. vivax malaria, from individuals exposed to P. falciparum,
from individuals with unrelated diseases or healthy controls
Distribution
Distribution of the OD492 data for sera from individuals with patent P. vivax malaria, from individuals exposed to P. falciparum,
from individuals with unrelated diseases or healthy controls. The symbols represent the reactivity of each serum sample tested
in duplicate at 1:100 dilution against the indicated recombinant proteins. The abbreviations are as follow: A) Pv= individuals
with P. vivax malaria (n = 200), B) Pf= individuals from areas where P. falciparum malaria is endemic (n = 53), C) Cha = individu-
als with Chagas Disease (n = 21), D) Syp = individuals with syphilis (n = 21), E) HBV = individuals with hepatitis B (n = 19), F)
HCV= individuals with hepatitis C (n = 21), G) HTLV = individuals with HTLV (n = 14), H) HIV= individuals with HIV (n = 12),
I) ANA = individuals positive for antinuclear antibodies (n = 10), J) RF = individuals positive for rheumatoid factors (n = 10), L)
Healthy = Healthy individuals (n = 49). Sera from African individuals exposed to P. falciparum were tested only against recom-
binant protein His6-MSP119. The horizontal line inside the drops for each recombinant protein represents the cut-off values
(0.127, 0.170, 0.198 and 0.500 for GST-MSP119, His6-MSP119, His6-MSP119-PADRE and yMSP119-PADRE, respectively).
recombinant proteins produced in E. coli or in Pichia pas- during experimental infection in primates. Nevertheless,
toris in their ability to be recognized by IgG antibodies of we were able to determine that from the 111 primo-
Brazilian individuals with patent P. vivax infection. Our infected individuals that we evaluated, 101 (90.9%) had
study demonstrated that, for the Brazilian population, an specific IgG to MSP119. This information is important and
ELISA using a single recombinant protein based on the P. suggests that IgG antibodies specific for MSP119 are suita-
vivax MSP119 kDa can serve as the basis for the develop- ble for testing individuals who are traveling or have
ment of a sensitive serological test that can be used for epi- traveled for the first time through malaria endemic areas.
demiological studies, screening blood donors and On the other hand, the persistence of the IgG antibodies
diagnosis of P. vivax malaria. specific for MSP119 is still a matter that has to be further
evaluated. In previous studies we determined that the
So far, we do not have an estimate of the timing required antibody titers decreased relatively rapidly after treatment
after mosquito bite for the appearance of specific antibod- [8]. However, studies are underway using these recently
ies. To be accurate, this information should be obtained generated recombinant proteins.
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6. Malaria Journal 2003, 2 http://www.malariajournal.com/content/2/1/39
An important observation from our study was the fact that Authors' contributions
sera from African individuals naturally exposed to P. falci- MHCR carried out all the serological assays. MGC gener-
parum failed to cross-react with the recombinant protein ated and purified the recombinant proteins His6-MSP119
His6-MSP119 (Figure 2). As a control, 39 of these sera were and His6-MSP119-PADRE. RLDM collected part of the
also tested against a recombinant protein derived of the serum samples from P. vivax malaria individuals. OCF
MSP-2 of P. falciparum. The percentage of responders was participated in the design of the study and the supply of
69.2% (data not shown). The lack of cross-reactivity may the serum samples from blood bank donors and drafted
have several implications and should be further evaluated the manuscript. MMR participated in the design of the
in the light of the current knowledge that both MSP119 study and drafted the manuscript. ISS conceived of the
share similarities in their predicted tertiary structures [21]. study and participated in all aspects of its design, execu-
For epidemiological studies, for the screening of blood tion, coordination and manuscript preparation. All
donors and the serological diagnosis of P. vivax malaria, authors read and approved the final manuscript.
the lack of cross reactivity can be a major advantage. Nev-
ertheless, the absence of cross-recognition of P. vivax Acknowledgments
MSP119 by antibodies from P. falciparum-exposed individ- This work was supported by a grant from the Fundação de Amparo a
uals has may also have immunological consequences at Pesquisa do Estado de São Paulo (FAPESP). MHCR, MMR and ISS are sup-
the level of acquired immunity and vaccine development ported by fellowships from Conselho Nacional de Desenvolvimento Cientí-
fico e Tecnológico (CNPq). Also, the Ethics Committee of the University
in areas where both malarias are prevalent. Detailed stud-
of São Paulo approved it. The authors would like to thank Dr. Marcelo U.
ies will be required to determine whether sera from P. Ferreira and Dr. Silvia di Santi for kindly providing the sera from individuals
vivax infected individuals also fail to recognize recom- from West Africa, Dr. MUF for providing recombinant protein MSP-2 of P.
binant proteins representing the P. falciparum MSP119. falciparum, and Drs. Michel Rabinovitch and MUF for critical reading of the
manuscript.
Recently, a direct sandwich ELISA to detect antibodies
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