JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Gene expression profile in long-term non progressor HIV infected patients: in search of potential resistance factors.
Mol. Immunol.
PUBLISHED: 05-27-2014
Show Abstract
Hide Abstract
Long-term non-progressors (LTNP) represent a minority (1-5%) of HIV-infected individuals characterized by documented infection for more than 7-10 years, a stable CD4+ T cell count over 500/mm(3) and low viremia in the absence of antiretroviral treatment. Protective factors described so far such as the CCR5delta32 deletion, protective HLA alleles, or defective viruses fail to fully explain the partial protection phenotype. The existence of additional host resistance mechanisms in LTNP patients was investigated here using a whole human genome microarray study comparing gene expression profiles of unstimulated peripheral blood mononuclear cells from LTNP patients, HIV-1 infected patients under antiretroviral therapy with CD4+ T cell levels above 500/mm(3) (ST), as well as healthy individuals. Genes that were up- or downregulated exclusively in LTNP, ST or in both groups in comparison to controls were identified and classified in functional categories using Ingenuity Pathway Analysis. ST and LTNP patient groups revealed distinct genetic profiles, regarding gene number in each category and up- or downregulation of specific genes, which could have a bearing on the outcome of each group. We selected some relevant genes to validate the differential expression using quantitative real-time qRT-PCR. Among others, we found several genes related to the canonical Wnt/beta-catenin signaling pathway. Our results identify new possible host genes and molecules that could be involved in the mechanisms leading to the slower progression to AIDS and sustained CD4+ T cell counts that is peculiar to LTNP patients.
Related JoVE Video
Contribution of the Retrovirus Epidemiology Donor Study (REDS) to research on blood transfusion safety in Brazil.
Rev Bras Hematol Hemoter
PUBLISHED: 05-03-2014
Show Abstract
Hide Abstract
The Retrovirus Epidemiology Donor Study (REDS) program was established in the United States in 1989 with the purpose of increasing blood transfusion safety in the context of the HIV/AIDS and human T-lymphotropic virus epidemics. REDS and its successor, REDS-II were at first conducted in the US, then expanded in 2006 to include international partnerships with Brazil and China. In 2011, a third wave of REDS renamed the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) was launched. This seven-year research program focuses on both blood banking and transfusion medicine research in the United States of America, Brazil, China, and South Africa. The main goal of the international programs is to reduce and prevent the transmission of HIV/AIDS and other known and emerging infectious agents through transfusion, and to address research questions aimed at understanding global issues related to the availability of safe blood. This article describes the contribution of REDS-II to transfusion safety in Brazil. Articles published from 2010 to 2013 are summarized, including database analyses to characterize blood donors, deferral rates, and prevalence, incidence and residual risk of the main blood-borne infections. Specific studies were developed to understand donor motivation, the impact of the deferral questions, risk factors and molecular surveillance among HIV-positive donors, and the natural history of Chagas disease. The purpose of this review is to disseminate the acquired knowledge and briefly summarize the findings of the REDS-II studies conducted in Brazil as well as to introduce the scope of the REDS-III program that is now in progress and will continue through 2018.
Related JoVE Video
Accuracy of a probabilistic record-linkage methodology used to track blood donors in the Mortality Information System database.
Cad Saude Publica
PUBLISHED: 02-17-2014
Show Abstract
Hide Abstract
The probabilistic record linkage (PRL) is based on a likelihood score that measures the degree of similarity of several matching variables. Screening test results for different diseases are available for the blood donor population. In this paper, we describe the accuracy of a PRL process used to track blood donors from the Fundação Pró-Sangue (FPS) in the Mortality Information System (SIM), in order that future studies might determine the blood donor's cause of death. The databases used for linkage were SIM and the database made up of individuals that were living (200 blood donors in 2007) and dead (196 from the Hospital das Clinicas de São Paulo that died in 2001-2005). The method consists of cleaning and linking the databases using three blocking steps comparing the variables "Name/Mother's Name/ Date of Birth" to determine a cut-off score. For a cut-off score of 7.06, the sensitivity and specificity of the method is 94.4% (95%CI: 90.0-97.0) and 100% (95%CI: 98.0-100.0), respectively. This method can be used in studies that aim to track blood donors from the FPS database in SIM.
Related JoVE Video
Epstein-Barr Viral Load is Associated to Response in AIDS-Related Lymphomas.
Indian J Hematol Blood Transfus
PUBLISHED: 02-08-2014
Show Abstract
Hide Abstract
AIDS-related lymphoma (ARL) development is associated to immunodeficiency state with proliferation of B-cells driven by HIV itself and EBV infection. However, Epstein-Barr DNA is not detected in malignant cells of all ARL subtypes. A prospective and controlled study to analyze EBV viral load (VL) in plasma and peripheral blood mononuclear cells (PBMC) of ARL patients was performed to analyze if Epstein-Barr VL could be related to response in these patients. Fifteen patients with ARL were included in this study with measurement of EBV VL at three different periods of time: at lymphoma diagnosis, upon completion of chemotherapy, and 3 months after. Two control groups composed by HIV-negative and HIV-positive patients were also evaluated for EBV VL comparison. In situ hybridization for EBER was performed on diagnostic samples of all ARL patients. Median EBV VL in PBMC and plasma had a significant decrease (p = 0.022 and p = 0.003, respectively) after ARL treatment. EBER was positive in 7 (46.7 %) cases. Median EBV VL in PBMC before lymphoma treatment in patients positive for EBER was significantly higher compared to EBER negative cases (p = 0.041). Reduction of EBV viral load during treatment of lymphoma could be predictive of response. EBER expression was associated to advanced stages of disease and worse immune status. Our study suggests that measurement of EBV VL during ARL treatment could be used as a marker for response, but further studies are needed to validate this association.
Related JoVE Video
Deep Sequencing of HIV-1 near Full-Length Proviral Genomes Identifies High Rates of BF1 Recombinants Including Two Novel Circulating Recombinant Forms (CRF) 70_BF1 and a Disseminating 71_BF1 among Blood Donors in Pernambuco, Brazil.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The findings of frequent circulation of HIV-1 subclade F1 viruses and the scarcity of BF1 recombinant viruses based on pol subgenomic fragment sequencing among blood donors in Pernambuco (PE), Northeast of Brazil, were reported recently. Here, we aimed to determine whether the classification of these strains (n?=?26) extends to the whole genome sequences.
Related JoVE Video
HCV genotypes, characterization of mutations conferring drug resistance to protease inhibitors, and risk factors among blood donors in São Paulo, Brazil.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Hepatitis C virus (HCV) infection is a global health problem estimated to affect almost 200 million people worldwide. The aim of this study is to analyze the subtypes and existence of variants resistant to protease inhibitors and their association with potential HCV risk factors among blood donors in Brazil.
Related JoVE Video
HIV Type 1 Subtype BF Leads to Faster CD4(+) T Cell Loss Compared to Subtype B.
AIDS Res. Hum. Retroviruses
PUBLISHED: 09-06-2013
Show Abstract
Hide Abstract
Abstract Although it has been suggested that biological differences among HIV-1 subtypes exist, their possible influence on disease progression has not been fully revealed. In particular, the increasing emergence of recombinants stresses the need to characterize disease presentation in persons infected by these diverse HIV-1 forms. We explored this issue among 83 Brazilian subjects infected with either HIV-1 subtype B or recombinant subtype BF, all followed since incident infection in a cohort study. Viral subtypes were assigned by full length sequencing of HIV-1 genomes. We observed that the baseline measures for CD4(+) T cells and viral load did not differ between the groups. However, longitudinal analysis revealed that subtype BF was clearly associated with a faster CD4(+) T cell decline compared to infection with subtype B, in spite of a similar plasma HIV-1 load. While subtype B-infected subjects presented a loss of 3.6 CD4(+) T cells/?l per month, subtype BF-infected individuals showed a monthly decay of 6.3 CD4(+) T cells/?l (p<0.01). The time to reach 350 CD4(+) T cells/?l and the time to start antiretroviral treatment were also shorter in subtype BF-infected persons. The elucidation of an accelerated CD4(+) T cell loss associated with subtype BF suggests that this HIV-1 genetic form could be more pathogenic than subtype B.
Related JoVE Video
Methodological Guidelines for Reducing the Complexity of Data Warehouse Development for Transactional Blood Bank Systems.
Decis Support Syst
PUBLISHED: 06-05-2013
Show Abstract
Hide Abstract
Over time, data warehouse (DW) systems have become more difficult to develop because of the growing heterogeneity of data sources. Despite advances in research and technology, DW projects are still too slow for pragmatic results to be generated. Here, we address the following question: how can the complexity of DW development for integration of heterogeneous transactional information systems be reduced? To answer this, we proposed methodological guidelines based on cycles of conceptual modeling and data analysis, to drive construction of a modular DW system. These guidelines were applied to the blood donation domain, successfully reducing the complexity of DW development.
Related JoVE Video
Undisclosed human immunodeficiency virus risk factors identified through a computer-based questionnaire program among blood donors in Brazil.
Transfusion
PUBLISHED: 03-22-2013
Show Abstract
Hide Abstract
BACKGROUND: Human immunodeficiency virus (HIV) risk factor screening among blood donors remains a cornerstone for the safety of blood supply and is dependent on prospective donor self-disclosure and an attentive predonation interview. Audio computer-assisted structured interview (ACASI) has been shown to increase self-reporting of risk behaviors. STUDY DESIGN AND METHODS: This cross-sectional study was conducted between January 2009 and March 2011 at four Brazilian blood centers to identify the population of HIV-negative eligible blood donors that answered face-to-face interviews without disclosing risks, but subsequently disclosed deferrable risk factors by ACASI. Compared to the donor interview, the ACASI contained expanded content on demographics, sexual behavior, and other HIV risk factors questions. RESULTS: A total of 901 HIV-negative blood donors were interviewed. On the ACASI, 13% of donors (n?=?120) declared a risk factor that would have resulted in deferral that was not disclosed during the face-to-face assessment. The main risk factors identified were recent unprotected sex with an unknown or irregular partner (49 donors), sex with a person with exposure to blood or fluids (26 donors), multiple sexual partners (19 donors), and male-male sexual behavior (10 donors). Independent factors associated with the disclosure of any risk factor for HIV were age (?40 years vs. 18-25 years; adjusted odds ratio [AOR],?0.45; 95% confidence interval [CI], 0.23-0.88) and blood center (Hemope vs. Hemominas; AOR,?2.51; 95% CI, 1.42-4.44). CONCLUSION: ACASI elicited increased disclosure of HIV risk factors among blood donors. ACASI may be a valuable modality of interview to be introduced in Brazilian blood banks.
Related JoVE Video
HIV genotypes and primary drug resistance among HIV-seropositive blood donors in Brazil: role of infected blood donors as sentinel populations for molecular surveillance of HIV.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 03-20-2013
Show Abstract
Hide Abstract
There are few surveillance studies analyzing genotypes or primary (transmitted) drug resistance in HIV-infected blood donors in Brazil. The aim of this study was to characterize patterns of HIV genotypes and primary resistance among HIV-seropositive donors identified at 4 geographically dispersed blood centers in Brazil.
Related JoVE Video
Predictors of low haematocrit among repeat donors in São Paulo, Brazil: Eleven year longitudinal analysis.
Transfus. Apher. Sci.
PUBLISHED: 02-28-2013
Show Abstract
Hide Abstract
Few longitudinal studies have examined the long-term effect on deferral for low haematocrit (Hct) or haemoglobin, indicators of presence of anaemia. This study retrospectively analysed 11years of donation history to examine predictors related to such deferrals among repeat blood donors.
Related JoVE Video
Temporal distribution of blood donations in three Brazilian blood centers and its repercussion on the blood supply.
Rev Bras Hematol Hemoter
PUBLISHED: 01-27-2013
Show Abstract
Hide Abstract
Seasonal distribution of blood donation hinders efforts to provide a safe and adequate blood supply leading to chronic and persistent shortages. This study examined whether holidays, geographical area and donation type (community versus replacement) has any impact on the fluctuation of donations.
Related JoVE Video
Electrocardiographic abnormalities in Trypanosoma cruzi seropositive and seronegative former blood donors.
PLoS Negl Trop Dis
PUBLISHED: 01-10-2013
Show Abstract
Hide Abstract
Blood donor screening leads to large numbers of new diagnoses of Trypanosoma cruzi infection, with most donors in the asymptomatic chronic indeterminate form. Information on electrocardiogram (ECG) findings in infected blood donors is lacking and may help in counseling and recognizing those with more severe disease.
Related JoVE Video
Genome Wide Association Study (GWAS) of Chagas Cardiomyopathy in Trypanosoma cruzi Seropositive Subjects.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Familial aggregation of Chagas cardiac disease in T. cruzi-infected persons suggests that human genetic variation may be an important determinant of disease progression.
Related JoVE Video
Anti-Trypanosoma cruzi cross-reactive antibodies detected at high rate in non-exposed individuals living in non-endemic regions: seroprevalence and association to other viral serologies.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Cross-reactive antibodies are characterized by their recognition of antigens that are different from the trigger immunogen. This happens when the similarity between two different antigenic determinants becomes adequate enough to enable a specific binding with such cross-reactive antibodies. In the present manuscript, we report the presence, at an "abnormal" high frequency, of antibodies in blood samples from French human subjects cross-reacting with a synthetic-peptide antigen derived from a Trypanosoma cruzi (T. cruzi) protein sequence. As the vector of T. cruzi is virtually confined to South America, the parasite is unlikely to be the trigger immunogen of the cross-reactive antibodies detected in France. At present, the cross-reactive antibodies are measured by using an in-house ELISA method that employs the T. cruzi -peptide antigen. However, to underline their cross-reactive characteristics, we called these antibodies "Trypanosoma cruzi Cross Reactive Antibodies" or TcCRA. To validate their cross-reactive nature, these antibodies were affinity-purified from plasma of healthy blood donor and were then shown to specifically react with the T. cruzi parasite by immunofluorescence. Seroprevalence of TcCRA was estimated at 45% in serum samples of French blood donors while the same peptide-antigen reacts with about 96% of T. cruzi -infected Brazilian individuals. In addition, we compared the serology of TcCRA to other serologies such as HSV 1/2, EBV, HHV-6, CMV, VZV, adenovirus, parvovirus B19, mumps virus, rubella virus, respiratory syncytial virus, measles and enterovirus. No association was identified to any of the tested viruses. Furthermore, we tested sera from different age groups for TcCRA and found a progressive acquisition starting from early childhood. Our findings show a large seroprevalence of cross-reactive antibodies to a well-defined T. cruzi antigen and suggest they are induced by a widely spread immunogen, acquired from childhood. The etiology of TcCRA and their clinical relevance still need to be investigated.
Related JoVE Video
Variability of HIV-1 genomes among children and adolescents from São Paulo, Brazil.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Genetic variability is a major feature of the human immunodeficiency virus type 1 (HIV-1) and considered the key factor to frustrating efforts to halt the virus epidemic. In this study, we aimed to investigate the genetic variability of HIV-1 strains among children and adolescents born from 1992 to 2009 in the state of Sao Paulo, Brazil.
Related JoVE Video
Vasovagal reactions in whole blood donors at three REDS-II blood centers in Brazil.
Transfusion
PUBLISHED: 11-11-2011
Show Abstract
Hide Abstract
In Brazil little is known about adverse reactions during donation and the donor characteristics that may be associated with such events. Donors are offered snacks and fluids before donating and are required to consume a light meal after donation. For these reasons the frequency of reactions may be different than those observed in other countries.
Related JoVE Video
Interdonation intervals and patterns of return among blood donors in Brazil.
Transfusion
PUBLISHED: 10-07-2011
Show Abstract
Hide Abstract
In Brazil, most donations come from repeat donors, but there are little data on return behavior of donors.
Related JoVE Video
Human immunodeficiency virus prevalence, incidence, and residual risk of transmission by transfusions at Retrovirus Epidemiology Donor Study-II blood centers in Brazil.
Transfusion
PUBLISHED: 10-07-2011
Show Abstract
Hide Abstract
In Brazil nationally representative donor data are limited on human immunodeficiency virus (HIV) prevalence, incidence, and residual transfusion risk. The objective of this study was to analyze HIV data obtained over 24 months by the Retrovirus Epidemiology Donor Study-II program in Brazil.
Related JoVE Video
Correlation between LTR point mutations and proviral load levels among human T cell lymphotropic virus type 1 (HTLV-1) asymptomatic carriers.
Virol. J.
PUBLISHED: 09-29-2011
Show Abstract
Hide Abstract
In vitro studies have demonstrated that deletions and point mutations introduced into each 21 bp imperfect repeat of Tax-responsive element (TRE) of the genuine human T-cell leukemia virus type I (HTLV-1) viral promoter abolishes Tax induction. Given these data, we hypothesized that similar mutations may affect the proliferation of HTLV-1-infected cells and alter the proviral load (PvL). To test this hypothesis, we conducted a cross-sectional genetic analysis to compare the near-complete LTR nucleotide sequences that cover the TRE1 region in a sample of HTLV-1 asymptomatic carriers with different PvL burden.
Related JoVE Video
Antiretroviral drug resistance in a respondent-driven sample of HIV-infected men who have sex with men in Brazil.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 08-23-2011
Show Abstract
Hide Abstract
: There are few studies on HIV subtypes and primary and secondary antiretroviral drug resistance (ADR) in community-recruited samples in Brazil. We analyzed HIV clade diversity and prevalence of mutations associated with ADR in men who have sex with men in all five regions of Brazil.
Related JoVE Video
Number of recent sexual partners among blood donors in Brazil: associations with donor demographics, donation characteristics, and infectious disease markers.
Transfusion
PUBLISHED: 07-14-2011
Show Abstract
Hide Abstract
Brazilian blood centers ask candidate blood donors about the number of sexual partners in the past 12 months. Candidates who report a number over the limit are deferred. We studied the implications of this practice on blood safety.
Related JoVE Video
Characterization of partial and near full-length genomes of HIV-1 strains sampled from recently infected individuals in São Paulo, Brazil.
PLoS ONE
PUBLISHED: 04-14-2011
Show Abstract
Hide Abstract
Genetic variability is a major feature of human immunodeficiency virus type 1 (HIV-1) and is considered the key factor frustrating efforts to halt the HIV epidemic. A proper understanding of HIV-1 genomic diversity is a fundamental prerequisite for proper epidemiology, genetic diagnosis, and successful drugs and vaccines design. Here, we report on the partial and near full-length genomic (NFLG) variability of HIV-1 isolates from a well-characterized cohort of recently infected patients in São Paul, Brazil.
Related JoVE Video
Prevalence, incidence density, and genotype distribution of GB virus C infection in a cohort of recently HIV-1-infected subjects in Sao Paulo, Brazil.
PLoS ONE
PUBLISHED: 03-07-2011
Show Abstract
Hide Abstract
The results of previous studies elsewhere have indicated that GB virus C (GBV-C) infection is frequent in patients infected with the human immunodeficiency virus type 1 (HIV-1) due to similar transmission routes of both viruses. The aim of this study was to determine the prevalence, incidence density and genotypic characteristics of GBV-C in this population.
Related JoVE Video
Parvovirus among patients with cytopenia of unknown origin in Brazil: a case-control study.
J. Clin. Microbiol.
PUBLISHED: 02-09-2011
Show Abstract
Hide Abstract
The molecular prevalence of human parvovirus B19V (B19V) in bone marrow (BM) samples from 120 cases with cytopenias of unknown etiology was compared with that in samples from 45 BM donors (control group 1) and 120 oncohematological patients (control group 2) to determine the role that B19V genotypes may play in unexplained cytopenias. Of the 285 participants, the BM samples of 39 (13.7%) contained B19V DNA (21 with genotype 1, 5 with genotype 2, and 13 with genotype 3). The prevalences of B19V were similar between case and control subjects (15.0% versus 12.7%, respectively). Genotypes 2 and 3 were associated with older age and were detected in similar proportions between case and control group 2 subjects. The results of this study do not support a role for B19V genotype variants in the etiology of unexplained cytopenias.
Related JoVE Video
The Brazilian network for HIV-1 genotyping external quality control assurance programme.
J Int AIDS Soc
PUBLISHED: 02-02-2011
Show Abstract
Hide Abstract
The Brazilian network for genotyping is composed of 21 laboratories that perform and analyze genotyping tests for all HIV-infected patients within the public system, performing approximately 25,000 tests per year. We assessed the interlaboratory and intralaboratory reproducibility of genotyping systems by creating and implementing a local external quality control evaluation. Plasma samples from HIV-1-infected individuals (with low and intermediate viral loads) or RNA viral constructs with specific mutations were used. This evaluation included analyses of sensitivity and specificity of the tests based on qualitative and quantitative criteria, which scored laboratory performance on a 100-point system. Five evaluations were performed from 2003 to 2008, with 64% of laboratories scoring over 80 points in 2003, 81% doing so in 2005, 56% in 2006, 91% in 2007, and 90% in 2008 (Kruskal-Wallis, p = 0.003). Increased performance was aided by retraining laboratories that had specific deficiencies. The results emphasize the importance of investing in laboratory training and interpretation of DNA sequencing results, especially in developing countries where public (or scarce) resources are used to manage the AIDS epidemic.
Related JoVE Video
Evaluation of primary resistance to HIV entry inhibitors among brazilian patients failing reverse transcriptase/protease inhibitors treatment reveal high prevalence of maraviroc resistance-related mutations.
AIDS Res. Hum. Retroviruses
PUBLISHED: 10-26-2010
Show Abstract
Hide Abstract
Entry inhibitor is a new class of drugs that target the viral envelope protein. This region is variable; hence resistance to these drugs may be present before treatment. The aim of this study was to analyze the frequency of patients failing treatment with transcriptase reverse and protease inhibitors that would respond to the entry inhibitors Enfuvirtide, Maraviroc, and BMS-806. The study included 100 HIV-1 positive patients from one outpatient clinic in the city of Sao Paulo, for whom a genotype test was requested due to treatment failure. Proviral DNA was amplified and sequenced for regions of gp120 and gp41. A total of 80 could be sequenced and from those, 73 (91.3%), 5 (6.3%) and 2 (2.5%) were classified as subtype B, F, and recombinants (B/ F and B/C), respectively. CXCR4 co-receptor use was predicted in 30% of the strains. Primary resistance to Enfuvirtide was found in 1.3%, following the AIDS Society consensus list, and 10% would be considered resistant if a broader criterion was used. Resistance to BMS-806 was higher; 6 (7.5%), and was associated to non-B strains. Strikingly, 27.5% of samples harbored one or more mutation among A316T, I323V, and S405A, which have been related to decreased susceptibility of Maraviroc; 15% of them among viruses predictive to be R5. A more common mutation was A316T, which was associated to the Brazilian B strain harboring the GWGR motif at the tip of V3 loop and their derivative sequences. These results may be impact guidelines for genotype testing and treatment in Brazil.
Related JoVE Video
Enhanced classification of Chagas serologic results and epidemiologic characteristics of seropositive donors at three large blood centers in Brazil.
Transfusion
PUBLISHED: 06-26-2010
Show Abstract
Hide Abstract
A major problem in Chagas disease donor screening is the high frequency of samples with inconclusive results. The objective of this study was to describe patterns of serologic results among donors to the three Brazilian REDS-II blood centers and correlate with epidemiologic characteristics.
Related JoVE Video
Unexpected diversity of cellular immune responses against Nef and Vif in HIV-1-infected patients who spontaneously control viral replication.
PLoS ONE
PUBLISHED: 05-25-2010
Show Abstract
Hide Abstract
HIV-1-infected individuals who spontaneously control viral replication represent an example of successful containment of the AIDS virus. Understanding the anti-viral immune responses in these individuals may help in vaccine design. However, immune responses against HIV-1 are normally analyzed using HIV-1 consensus B 15-mers that overlap by 11 amino acids. Unfortunately, this method may underestimate the real breadth of the cellular immune responses against the autologous sequence of the infecting virus.
Related JoVE Video
Human immunodeficiency virus test-seeking blood donors in a large blood bank in São Paulo, Brazil.
Transfusion
PUBLISHED: 04-30-2010
Show Abstract
Hide Abstract
Persons with human immunodeficiency virus (HIV) risk behaviors are excluded from donation to reduce the risk of transfusion-transmitted infection. Persons donating to be tested for HIV may therefore deny risk behaviors.
Related JoVE Video
Characterization and frequency of a newly identified HIV-1 BF1 intersubtype circulating recombinant form in São Paulo, Brazil.
Virol. J.
PUBLISHED: 01-28-2010
Show Abstract
Hide Abstract
HIV circulating recombinant forms (CRFs) play an important role in the global and regional HIV epidemics, particularly in regions where multiple subtypes are circulating. To date, several (>40) CRFs are recognized worldwide with five currently circulating in Brazil. Here, we report the characterization of near full-length genome sequences (NFLG) of six phylogenetically related HIV-1 BF1 intersubtype recombinants (five from this study and one from other published sequences) representing CRF46_BF1.
Related JoVE Video
Demographic profile of blood donors at three major Brazilian blood centers: results from the International REDS-II study, 2007 to 2008.
Transfusion
PUBLISHED: 12-10-2009
Show Abstract
Hide Abstract
The profile of blood donors changed dramatically in Brazil over the past 20 years, from remunerated to nonremunerated and then from replacement to community donors. Donor demographic data from three major blood centers establish current donation profiles in Brazil, serving as baseline for future analyses and tracking longitudinal changes in donor characteristics.
Related JoVE Video
The impact of simple donor education on donor behavioral deferral and infectious disease rates in São Paulo, Brazil.
Transfusion
PUBLISHED: 12-09-2009
Show Abstract
Hide Abstract
Studies have shown that human immunodeficiency virus (HIV) residual risk is higher in Brazilian than in US and European blood donors, probably due to failure to defer at-risk individuals in Brazil. This study assessed the impact of an educational brochure in enhancing blood donors knowledge about screening test window phase and reducing at-risk individuals from donating.
Related JoVE Video
GB virus type C infection modulates T-cell activation independently of HIV-1 viral load.
AIDS
PUBLISHED: 09-24-2009
Show Abstract
Hide Abstract
Many clinical studies have suggested a beneficial effect of GB virus type C (GBV-C) on the course of HIV-1 infection, but the mechanisms involved in such amelioration are not clear. As recent evidence has implicated cellular activation in HIV-1 pathogenesis, we investigated the effect of GBV-C viremia on T-cell activation in early HIV-1 infection.
Related JoVE Video
Impact of allogeneic 2-RBC apheresis on iron stores of Brazilian blood donors.
Transfus. Apher. Sci.
PUBLISHED: 07-16-2009
Show Abstract
Hide Abstract
One limiting factor for automated two-red blood cells collections (2-RBC) is its potential iron depletion. We analyzed hematological parameters and iron balance before, two and four months after 2-RBC of 96 non-supplemented male donors. Four months after 2-RBC, ferritin level was significantly lower (P<0.01) than baseline levels and the number of donors who presented ferritin <30 ng/ml increased from 18 to 47. We concluded that four months was not sufficient for iron recuperation in the population studied. In an attempt to avoid iron depletion after 2-RBC, we recommend augmentation in the interval between blood donations and pre-donation ferritin measurement.
Related JoVE Video
Profile of blood donors with serologic tests reactive for the presence of syphilis in São Paulo, Brazil.
Transfusion
PUBLISHED: 05-30-2009
Show Abstract
Hide Abstract
Syphilis screening of blood donors is a common practice worldwide, but very little is known about the meaning of a positive serologic test for syphilis in blood donors and the risk profile of these donors. The aim of this study was to determine the demographic characteristics and risk behaviors of blood donors with recent and past syphilis and their implications for blood bank testing and deferral strategies.
Related JoVE Video
Near full-length genome analysis of low prevalent human immunodeficiency virus type 1 subclade F1 in São Paulo, Brazil.
Virol. J.
PUBLISHED: 05-05-2009
Show Abstract
Hide Abstract
The genetic diversity of the human immunodeficiency virus type 1 (HIV-1) is critical to lay the groundwork for the design of successful drugs or vaccine. In this study we aimed to characterize and define the molecular prevalence of HIV-1 subclade F1 currently circulating in São Paulo, Brazil.
Related JoVE Video
Distinct resistance mutation and polymorphism acquisition in HIV-1 protease of subtypes B and F1 from children and adult patients under virological failure.
Infect. Genet. Evol.
PUBLISHED: 05-01-2009
Show Abstract
Hide Abstract
The goal of this work was to compare the differences between human immunodeficiency virus type 1 (HIV-1) of B and F1 subtypes in the acquisition of major and minor protease inhibitor (PI)-associated resistance mutations and of other polymorphisms at the protease (PR) gene, through a cross sectional study. PR sequences from subtypes B and F1 isolates matched according to PI exposure time from Brazilian patients were included in this study. Sequences were separated in four groups: 24 and 90 from children and 141 and 99 from adults infected with isolates of subtypes F1 and B, respectively. For comparison, 211 subtype B and 79 subtype F1 PR sequences from drug-naïve individuals were included. Demographic and clinical data were similar among B- and F1-infected patients. In untreated patients, mutations L10V, K20R, and M36I were more frequent in subtype F1, while L63P, A71T, and V77I were more prevalent in subtype B. In treated patients, K20M, D30N, G73S, I84V, and L90M, were more prevalent in subtype B, and K20T and N88S were more prevalent in subtype F1. A higher proportion of subtype F1 than of subtype B strains containing other polymorphisms was observed. V82L mutation was present with increased frequency in isolates from children compared to isolates from adults infected with both subtypes. We could observe a faster resistance emergence in children than in adults, during treatment with protease inhibitors. This data provided evidence that, although rates of overall drug resistance do not differ between subtypes B and F1, the former accumulates resistance at higher proportion in specific amino acid positions of protease when compared to the latter.
Related JoVE Video
[Prevalence, risk factors and genetic characterization of human T-cell lymphotropic virus types 1 and 2 in patients infected with human immunodeficiency virus type 1 in the cities of Ribeirão Preto and São Paulo].
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 04-29-2009
Show Abstract
Hide Abstract
The aim of this study was to define the prevalence of human T cell lymphotropic virus types 1 and 2 in patients who were positive for human immunodeficiency virus type 1 in the State of São Paulo, Brazil. We evaluated 319 individuals infected with HIV type 1 who were attended at specialized clinics in two cities (Ribeirão Preto and São Paulo). The patients were interviewed and tested for antibodies against HTLV types 1 and 2 (Orthoâ HTLV-1/HTLV-2 Ab-Capture enzyme immunoassay). Direct DNA sequencing of polymerase chain reaction products from the tax region of HTLV type 2 and the long terminal repeat region of HTLV types 1 and 2 were performed to differentiate and determine the subtypes. The overall prevalence of anti-HTLV type 1 and 2 antibodies was 7.5% (24/319; 95% CI: 5.2-11.5). HTLV type 1 and 2 infection was associated with a history of injected drug use and with antibodies for hepatitis C virus (p < 0.001), but not with age (p = 0.2), sex (p = 0.9), sexual behavior or serological markers for sexually transmitted diseases (anti-Treponema pallidum, anti-human herpesvirus type 8 or anti-hepatitis B virus antibodies) (p > 0.05). HTLV DNA was detected in 13 out of 24 samples, of which 12 were characterized as HTLV subtype 2c and one as HTLV subtype 1a. Among the 12 HTLV type 2 samples, seven were from injected drug users, thus indicating that this route is an important risk factor for HTLV type 2 transmission among our population infected with HIV type 1.
Related JoVE Video
Seroprevalence of Kaposi sarcoma-associated herpesvirus and other serologic markers in the Brazilian Amazon.
Emerging Infect. Dis.
PUBLISHED: 04-01-2009
Show Abstract
Hide Abstract
To determine the presence of Kaposi sarcoma-associated herpesvirus (KSHV) and other serologic markers, we tested serum specimens of 339 Amerindians, 181 rural non-Amerindians, and 1,133 urban blood donors (13 Amerindians) in the Brazilian Amazon. High KSHV seroprevalence in children and inverse association with herpes simplex virus type 2 indicates predominant nonsexual transmission among Amerindians.
Related JoVE Video
WHO comparative evaluation of serologic assays for Chagas disease.
Transfusion
PUBLISHED: 03-05-2009
Show Abstract
Hide Abstract
Evaluation of commercially available test kits for Chagas disease for use in blood bank screening is difficult due to a lack of large and well-characterized specimen panels. This study presents a collaborative effort of Latin American blood centers and the World Health Organization (WHO) to establish such a panel.
Related JoVE Video
High human herpesvirus 8 (HHV-8) prevalence, clinical correlates and high incidence among recently HIV-1-infected subjects in Sao Paulo, Brazil.
PLoS ONE
PUBLISHED: 03-02-2009
Show Abstract
Hide Abstract
Human herpesvirus 8 (HHV-8) is the etiological agent for Kaposi Sarcoma, which occurs especially in HIV-infected subjects. HHV-8 infection and its clinical correlates have not been well characterized in recently HIV-1-infected subjects, especially men who have sex with men (MSM).
Related JoVE Video
Anemia screening in potential female blood donors: comparison of two different quantitative methods.
Transfusion
PUBLISHED: 01-02-2009
Show Abstract
Hide Abstract
Anemia screening before blood donation requires an accurate, quick, practical, and easy method with minimal discomfort for the donors. The aim of this study was to compare the accuracy of two quantitative methods of anemia screening: the HemoCue 201(+) (Aktiebolaget Leo Diagnostics) hemoglobin (Hb) and microhematocrit (micro-Hct) tests.
Related JoVE Video
Lack of evidence to support the association of a single IL28B genotype SNP rs12979860 with the HTLV-1 clinical outcomes and proviral load.
BMC Infect. Dis.
Show Abstract
Hide Abstract
The Interleukin 28B (IL28B) rs12979860 polymorphisms was recently reported to be associated with the human T-cell leukemia virus type 1 (HTLV-1) proviral load (PvL) and the development of the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP).
Related JoVE Video
Frequency of subtype B and F1 dual infection in HIV-1 positive, Brazilian men who have sex with men.
Virol. J.
Show Abstract
Hide Abstract
Because various HIV vaccination studies are in progress, it is important to understand how often inter- and intra-subtype co/superinfection occurs in different HIV-infected high-risk groups. This knowledge would aid in the development of future prevention programs. In this cross-sectional study, we report the frequency of subtype B and F1 co-infection in a clinical group of 41 recently HIV-1 infected men who have sex with men (MSM) in São Paulo, Brazil.
Related JoVE Video
Antibody levels correlate with detection of Trypanosoma cruzi DNA by sensitive polymerase chain reaction assays in seropositive blood donors and possible resolution of infection over time.
Transfusion
Show Abstract
Hide Abstract
The clinical significance of anti-Trypanosoma cruzi low-level reactive samples is incompletely understood. Polymerase chain reaction (PCR)-positive rates and antibody levels among seropositive blood donors in three countries are described.
Related JoVE Video
Motivation and social capital among prospective blood donors in three large blood centers in Brazil.
Transfusion
Show Abstract
Hide Abstract
Studies analyzing motivation factors that lead to blood donation have found altruism to be the primary motivation factor; however, social capital has not been analyzed in this context. Our study examines the association between motivation factors (altruism, self-interest, and response to direct appeal) and social capital (cognitive and structural) across three large blood centers in Brazil.
Related JoVE Video
The impact of policies to restrict the use of plasma containing products and apheresis platelets from female donors to mitigate transfusion related acute lung injury (TRALI) in Brazil.
Transfus. Apher. Sci.
Show Abstract
Hide Abstract
Although the incidence of TRALI is unknown in Brazil, some blood centers have adopted strategies to prevent TRALI. We evaluated the impact of three policies to mitigate TRALI on the supply of blood products: to divert the production of whole blood-derived plasma from female donors; to defer all female donors from apheresis platelet collections, and to defer only multiparous female donors from apheresis platelet collections.
Related JoVE Video
Evaluation of rapid tests for human immunodeficiency virus as a tool to detect recent seroconversion.
Braz J Infect Dis
Show Abstract
Hide Abstract
The identification of recent HIV infection is important for epidemiological studies and to monitor the epidemic. The objective of this study was to evaluate two rapid tests that are easily available to the Brazilian scientific community for using as markers of recent HIV infection. The Rapid Test - HIV-1/2 Bio-Manguinhos (Bio-Manguinhos/Fiocruz, Brazil) and the Rapid Check HIV 1&2 (NDI-UFES, Center for Infectious Diseases, Universidade Federal do Espírito Santo) were tested, using 489 samples with HIV positive serology, from blood donors, previously classified as recent or long-term infection by serological testing algorithm for recent HIV seroconversion (STARHS) or LS-HIV Vitros assay methods. The samples were diluted prior to testing (1:50 and 1:100 for the Rapid Test - HIV-1/2 Bio-Manguinhos, and 1:500 and 1:600 for the Rapid Check HIV 1&2). Negative samples were considered recent infection, whereas those showing any color intensity were associated with long-term infection. The best dilutions were 1:100 for HIV-1/2 Bio-Manguinhos test (Kappa = 0.840; overall agreement = 0.93), and 1:500 for the Rapid Check HIV 1&2 (Kappa = 0.867; overall agreement = 0.94). The results suggest that both rapid tests can be used to detect recent seroconversion.
Related JoVE Video
Prevalence of serologic markers for hepatitis B and C viruses in Brazilian blood donors and incidence and residual risk of transfusion transmission of hepatitis C virus.
Transfusion
Show Abstract
Hide Abstract
We evaluate the current prevalence of serologic markers for hepatitis B virus (HBV) and hepatitis C virus (HCV) in blood donors and estimated HCV incidence and residual transfusion-transmitted risk at three large Brazilian blood centers.
Related JoVE Video
Analysis of donor deferral at three blood centers in Brazil.
Transfusion
Show Abstract
Hide Abstract
The safety of the blood supply is ensured through several procedures from donor selection to testing of donated units. Examination of the donor deferrals at different centers provides insights into the role that deferrals play in transfusion safety.
Related JoVE Video
Blood transfusion utilization and recipient survival at Hospital das Clinicas in São Paulo, Brazil.
Transfusion
Show Abstract
Hide Abstract
The characteristics of blood recipients including diagnoses associated with transfusion and posttransfusion survival are unreported in Brazil. The goals of this analysis were: 1) to describe blood utilization according to clinical diagnoses and patient characteristics and 2) to determine the factors associated with survival of blood recipients.
Related JoVE Video
Human T-lymphotropic virus type 1 and type 2 seroprevalence, incidence, and residual transfusion risk among blood donors in Brazil during 2007-2009.
AIDS Res. Hum. Retroviruses
Show Abstract
Hide Abstract
Human T-lymphotropic virus type 1/2 (HTLV-1/2) infection is endemic in Brazil but representative donor prevalence and incidence data are lacking. All blood donations (2007-2009) from three blood centers in Brazil were studied. Samples reactive on one HTLV screening test (EIA) were retested with a different EIA; dual EIA reactivity correlated strongly with a confirmatory Western blot. Prevalence, incidence, and residual transfusion risk were calculated. Among 281,760 first-time donors, 363 were positive for HTLV on both EIAs (135 per 10(5), 95% CI 122-150). Prevalence differed considerably by region, from 83 to 222 per 10(5). Overall incidence rate was 3.6/10(5) person-years and residual transfusion risk was 5.0/10(6) per blood unit transfused. The logistic regression model showed significant associations with: age [adjusted odds ratio (aOR)=5.23 for age 50+ vs. <20], female sex (aOR=1.97), black (aOR=2.70 vs. white), and mixed skin colors (aOR=1.78 vs. white), and inversely with education (aOR=0.49, college vs. less than high school). HTLV testing with a dual-EIA strategy is feasible and can be useful in areas with low resources. Incidence and residual risk of HTLV-1 transmission by transfusion were relatively high and could be reduced by improving donor recruitment and selection in high prevalence areas. Blood center data may contribute to surveillance for HTLV infection.
Related JoVE Video
Faster HIV-1 disease progression among Brazilian individuals recently infected with CXCR4-utilizing strains.
PLoS ONE
Show Abstract
Hide Abstract
Primary HIV infection is usually caused by R5 viruses, and there is an association between the emergence of CCXR4-utilizing strains and faster disease progression. We characterized HIV-1 from a cohort of recently infected individuals in Brazil, predicted the viruss co-receptor use based on the env genotype and attempted to correlate virus profiles with disease progression.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.