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.
HIV Stigma as a Barrier to Retention in HIV Care at a General Hospital in Lima, Peru: A Case-Control Study.
AIDS Behav
PUBLISHED: 10-02-2014
Show Abstract
Hide Abstract
HIV stigma as a barrier to retention in HIV care has not been well-studied outside the United States. We conducted a case-control study in Lima, Peru to examine this issue. Cases were out-of-care for ?12 months (n = 66) and controls were recruited from patients in active care presenting for a clinic visit (n = 110). A previously validated HIV stigma scale with four domains was used. Associations between being out-of-care and each stigma domain were assessed using multivariable logistic regression. Stigma scores were highest for disclosure concerns. Modest associations were found for greater disclosure concerns (OR 1.16; 95 % CI 0.99, 1.36) and concerns with public attitudes (OR 1.20; 95 % CI 1.03, 1.40). Enacted stigma and negative self-image showed non-linear associations with being out-of-care that plateaued or declined, respectively, at higher levels of stigma. The threshold effect for enacted stigma warrants further exploration, while disclosure concerns may be especially amenable to intervention in this population.
Related JoVE Video
Multidrug-resistant tuberculosis and culture conversion with bedaquiline.
N. Engl. J. Med.
PUBLISHED: 08-21-2014
Show Abstract
Hide Abstract
Bedaquiline (Sirturo, TMC207), a diarylquinoline that inhibits mycobacterial ATP synthase, has been associated with accelerated sputum-culture conversion in patients with multidrug-resistant tuberculosis, when added to a preferred background regimen for 8 weeks.
Related JoVE Video
A protein-conjugate approach to develop a monoclonal antibody-based antigen detection test for the diagnosis of human brucellosis.
PLoS Negl Trop Dis
PUBLISHED: 06-01-2014
Show Abstract
Hide Abstract
Human brucellosis is most commonly diagnosed by serology based on agglutination of fixed Brucella abortus as antigen. Nucleic acid amplification techniques have not proven capable of reproducibly and sensitively demonstrating the presence of Brucella DNA in clinical specimens. We sought to optimize a monoclonal antibody-based assay to detect Brucella melitensis lipopolysaccharide in blood by conjugating B. melitensis LPS to keyhole limpet hemocyanin, an immunogenic protein carrier to maximize IgG affinity of monoclonal antibodies. A panel of specific of monoclonal antibodies was obtained that recognized both B. melitensis and B. abortus lipopolysaccharide epitopes. An antigen capture assay was developed that detected B. melitensis in the blood of experimentally infected mice and, in a pilot study, in naturally infected Peruvian subjects. As a proof of principle, a majority (7/10) of the patients with positive blood cultures had B. melitensis lipopolysaccharide detected in the initial blood specimen obtained. One of 10 patients with relapsed brucellosis and negative blood culture had a positive serum antigen test. No seronegative/blood culture negative patients had a positive serum antigen test. Analysis of the pair of monoclonal antibodies (2D1, 2E8) used in the capture ELISA for potential cross-reactivity in the detection of lipopolysaccharides of E. coli O157:H7 and Yersinia enterocolitica O9 showed specificity for Brucella lipopolysaccharide. This new approach to develop antigen-detection monoclonal antibodies against a T cell-independent polysaccharide antigen based on immunogenic protein conjugation may lead to the production of improved rapid point-of-care-deployable assays for the diagnosis of brucellosis and other infectious diseases.
Related JoVE Video
The isolation of Balamuthia mandrillaris from environmental sources from Peru.
Parasitol. Res.
PUBLISHED: 02-18-2014
Show Abstract
Hide Abstract
Balamuthia mandrillaris is an opportunistic free-living amoeba that has been reported to cause skin lesions and the fatal Balamuthia amoebic encephalitis (BAE) in humans and other animals. Currently, around 200 human BAE cases have been reported worldwide, although this number is considered to be underestimated. The highest number of BAE cases has been reported in the American continent, mainly in the southwest of the USA. Peru seems to be another hotspot for BAE with around 55 human cases having been identified, usually involving cutaneous infection, especially lesions in the central face area. The isolation of Balamuthia from environmental sources has been reported on only three prior occasions, twice from Californian soils and once from dust in Iran and so it seems that this amoeba is relatively rarely encountered in samples from the environment. We investigated that possibility of finding the amoebae in soil samples from different regions where clinical cases have been reported in Peru. Twenty-one samples were cultured in non-nutrient agar plates and were checked for the presence of B. mandrillaris-like trophozoites and/or cysts. Those samples that were positive for these amoebae by microscopic criteria were then confirmed by PCR amplification and DNA sequencing of the mitochondrial 16S rDNA gene of B. mandrillaris. We have detected the presence of B. mandrillaris in four samples collected in the regions of Piura (3) and Lima (1) where infection cases have been previously reported. We hypothesize that B. mandrillaris is present in Peru in soil and dust which therefore constitutes a source of the infection for the BAE cases previously reported in this country. Further studies should be carried out in the area to confirm the generality of this finding.
Related JoVE Video
CD80+ and CD86+ B cells as biomarkers and possible therapeutic targets in HTLV-1 associated myelopathy/tropical spastic paraparesis and multiple sclerosis.
J Neuroinflammation
PUBLISHED: 01-13-2014
Show Abstract
Hide Abstract
Human T-cell lymphotropic virus (HTLV-1) is the causative agent of the incapacitating, neuroinflammatory disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Currently, there are no disease-modifying therapies with long-term clinical benefits or validated biomarkers for clinical follow-up in HAM/TSP. Although CD80 and CD86 costimulatory molecules play prominent roles in immune regulation and reflect disease status in multiple sclerosis (MS), data in HAM/TSP are lacking.
Related JoVE Video
Extended spectrum ?-lactamase producers among nosocomial Enterobacteriaceae in Latin America.
Braz J Infect Dis
PUBLISHED: 01-03-2014
Show Abstract
Hide Abstract
To review the epidemiology of nosocomial extended spectrum ?-lactamase-producing Enterobacteriaceae in Latin America, a systematic search of the biomedical literature (PubMed) was performed for articles published since 2005. Rates of nosocomial infections caused by extended spectrum ?-lactamase-producing Enterobacteriaceae in Latin America have increased since 2005. Up to 32% of Escherichia coli and up to 58% of Klebsiella pneumoniae isolates are extended spectrum ?-lactamase-positive, rates that are higher than in other world regions. From a region-wide perspective, 11-25% of E. coli isolates and 45-53% of K. pneumoniae isolates were nonsusceptible to third-generation cephalosporins. At the country level, there was a wide range in Enterobacteriaceae resistance rates to third-generation cephalosporins, with especially high rates of resistance to E. coli in Guatemala, Honduras, and Mexico, and high resistance rates to Klebsiella spp. in Argentina, Brazil, Chile, Guatemala, Honduras, and Paraguay. Susceptibility of extended spectrum ?-lactamase-producing Enterobacteriaceae to cefepime, fluoroquinolones, ampicillin/sulbactam, aminoglycosides, and piperacillin/tazobactam has also been compromised, leaving the carbapenems, tigecycline, and colistin as the only antibiotics with >90% susceptibility rates. There is a steady increase in the prevalence and types of extended spectrum ?-lactamases produced by Enterobacteriaceae isolates in Latin American hospitals (particularly CTX-Ms), suggesting endemic conditions overlaid by clonal outbreaks. Appropriate treatment decisions and infection control strategies informed by surveillance of regional and local susceptibilities and mechanisms of resistance are required to mitigate this major public health concern.
Related JoVE Video
Use of third line antiretroviral therapy in Latin America.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Access to highly active antiretroviral therapy (HAART) is expanding in Latin America. Many patients require second and third line therapy due to toxicity, tolerability, failure, or a combination of factors. The need for third line HAART, essential for program planning, is not known.
Related JoVE Video
Brucella melitensis T Cell Epitope Recognition in Humans with Brucellosis in Peru.
Infect. Immun.
PUBLISHED: 10-14-2013
Show Abstract
Hide Abstract
Brucella melitensis, one of the causative agents of human brucellosis, causes acute, chronic, and relapsing infection. While T cell immunity in brucellosis has been extensively studied in mice, no recognized human T cell epitopes that might provide new approaches to classifying and prognosticating B. melitensis infection have ever been delineated. Twenty-seven pools of 500 major histocompatibility complex class II (MHC-II) restricted peptides were created by computational prediction of promiscuous MHC-II CD4(+) T cell derived from the top 50 proteins recognized by IgG in human sera on a genome level B. melitensis protein microarray. Gamma interferon (IFN-?) and interleukin-5 (IL-5) enzyme-linked immunospot (ELISPOT) analyses were used to quantify and compare Th1 and Th2 responses of leukapheresis-obtained peripheral blood mononuclear cells from Peruvian subjects cured after acute infection (n = 9) and from patients who relapsed (n = 5). Four peptide epitopes derived from 3 B. melitensis proteins (BMEI 1330, a DegP/HtrA protease; BMEII 0029, type IV secretion system component VirB5; and BMEII 0691, a predicted periplasmic binding protein of a peptide transport system) were found repeatedly to produce significant IFN-? ELISPOT responses in both acute-infection and relapsing patients; none of the peptides distinguished the patient groups. IL-5 responses against the panel of peptides were insignificant. These experiments are the first to systematically identify B. melitensis MHC-II-restricted CD4(+) T cell epitopes recognized by the human immune response, with the potential for new approaches to brucellosis diagnostics and understanding the immunopathogenesis related to this intracellular pathogen.
Related JoVE Video
Efficacy and duration of immunity after yellow fever vaccination: systematic review on the need for a booster every 10 years.
Am. J. Trop. Med. Hyg.
PUBLISHED: 09-06-2013
Show Abstract
Hide Abstract
Abstract. Current regulations stipulate a yellow fever (YF) booster every 10 years. We conducted a systematic review of the protective efficacy and duration of immunity of YF vaccine in residents of disease-endemic areas and in travelers to assess the need for a booster in these two settings and in selected populations (human immunodeficiency virus-infected persons, infants, children, pregnant women, and severely malnourished persons). Thirty-six studies and 22 reports were included. We identified 12 studies of immunogenicity, 8 of duration of immunity, 8 of vaccine response in infants and children, 7 of human-immunodeficiency virus-infected persons, 2 of pregnant women, and 1 of severely malnourished children. Based on currently available data, a single dose of YF vaccine is highly immunogenic and confers sustained life-long protective immunity against YF. Therefore, a booster dose of YF vaccine is not needed. Special considerations for selected populations are detailed.
Related JoVE Video
Ex vivo innate immune cytokine signature of enhanced risk of relapsing brucellosis.
PLoS Negl Trop Dis
PUBLISHED: 09-01-2013
Show Abstract
Hide Abstract
Brucellosis, a zoonotic infection caused by one of the Gram-negative intracellular bacteria of the Brucella genus, is an ongoing public health problem in Perú. While most patients who receive standard antibiotic treatment recover, 5-40% suffer a brucellosis relapse. In this study, we examined the ex vivo immune cytokine profiles of recovered patients with a history of acute and relapsing brucellosis.
Related JoVE Video
Algorithm for the diagnosis of smear-negative pulmonary tuberculosis in high-incidence resource-constrained settings.
Trop. Med. Int. Health
PUBLISHED: 08-18-2013
Show Abstract
Hide Abstract
Diagnosis of smear-negative pulmonary tuberculosis (SNPT) remains a challenge, particularly in resource-constrained settings. We evaluated a diagnostic algorithm that combines affordable laboratory tools and a clinical prediction rule (CPR).
Related JoVE Video
Current status of carbapenemases in Latin America.
Expert Rev Anti Infect Ther
PUBLISHED: 07-25-2013
Show Abstract
Hide Abstract
Enterobacteriaceae and non fermenting Gram-negative bacilli have become a threat to public health, in part due to their resistance to multiple antibiotic classes, which ultimately have led to an increase in morbidity and mortality. ?-lactams are currently the mainstay for combating infections caused by these microorganisms, and ?-lactamases are the major mechanism of resistance to this class of antibiotics. Within the ?-lactamases, carbapenemases pose one of the gravest threats, as they compromise one of our most potent lines of defense, the carbapenems. Carbapenemases are being continuously identified worldwide; and in Latin America, numerous members of these enzymes have been reported. In this region, the high incidence of reports implies that carbapenemases have become a menace and that they are an issue that must be carefully studied and analyzed.
Related JoVE Video
Genotyping of potentially pathogenic Acanthamoeba strains isolated from nasal swabs of healthy individuals in Peru.
Acta Trop.
PUBLISHED: 07-22-2013
Show Abstract
Hide Abstract
Free Living Amoebae (FLA) of Acanthamoeba genus are widely distributed in the environment and can be found in the air, soil and water; and have also been isolated from air-conditioning units. In humans, they are causative agents of a sight-threating infection of the cornea, Acanthamoeba keratitis (AK) and a fatal infection of the central nervous system known as Granulomatous Amoebic Encephalitis (GAE). In this study, a survey was conducted in order to determine the presence and pathogenic potential of free-living amoebae of Acanthamoeba genus in nasal swabs from individuals in two regions of Peru. Identification of isolates was based on cyst morphology and PCR-sequencing of the Diagnostic Fragment 3 to identify strains at the genotype level. The pathogenic potential of the isolates was also assayed using temperature and osmotolerance assays and extracellular proteases zymograms. The obtained results revealed that all isolated strains exhibited pathogenic potential. After sequencing the highly variable DF3 (Diagnostic Fragment 3) region in the 18S rRNA gene as previously described, genotype T4 was found to be the most common one in the samples included in this study but also genotype T15 was identified. To the best of our knowledge, this is the first study on the characterization of Acanthamoeba strains at the genotype level and the first report of genotype T4 and T15 in Peru.
Related JoVE Video
Strongyloides stercoralis infection complicating the central nervous system.
Handb Clin Neurol
PUBLISHED: 07-09-2013
Show Abstract
Hide Abstract
Strongyloides stercoralis is a nematode endemic in humid tropical regions. The life cycle of this parasite is complex and unique due to its capacity to cause autoinfection, resulting in chronic infections. Innate and adaptive immune responses are responsible for clearing the parasite. Many risk factors have been described, but the most important is living in or having visited an endemic area. The clinical presentation of strongyloidiasis is varied and ranges from asymptomatic chronic infection to hyperinfection syndrome. Hyperinfection syndrome is more common in patients with immunosuppresion due to therapy with corticosteroids, coinfection with human T-lymphotropic virus type I (HTLV-1), transplant patients, or patients receiving chemotherapy. Multiplication and migration of large parasite numbers cause worsening of the initial symptoms and leads to a high mortality rate. CNS involvement in strongyloidiasis has only been seen in patients with hyperinfection syndrome. Meningitis is the most common form of CNS involvement and gram-negative bacteria are the more frequent etiology. Repeated stool samples with concentration methods have a good sensitivity and specificity. In patients that are not from endemic areas serum antibody tests may be useful in the diagnosis. Treatment with a single dose of ivermectin is recommended for most patients. In severe or hyperinfection cases repeated doses may be needed.
Related JoVE Video
CD4+ T cell subsets and Tax expression in HTLV-1 associated diseases.
Pathog Glob Health
PUBLISHED: 07-03-2013
Show Abstract
Hide Abstract
Human T lymphotropic virus type 1 (HTLV-1) infection displays variable clinical manifestations. These include inflammatory diseases such as HTLV-1 associated myelopathy (HAM) or immunosuppressive conditions such as Strongyloides stercoralis hyperinfection. The viral protein, Tax causes activation and proliferation of T cells. We hypothesize that the expression of Tax in T cell subsets characterizes the clinical manifestations of HTLV-1. To test this hypothesis, we measured T helper 1 effector cells and regulatory T cells (Tregs) among Tax expressing lymphocytes from peripheral blood mononuclear cells (PBMCs) of 32 HTLV-1 infected patients with HAM, with S. stercoralis co-infection or with asymptomatic infection. We observed increased ratios of Th1/Treg among Tax expressing lymphocytes in HAM patients. These data suggest that the expression of Tax among the different target cells may explain the variable presentation of HTLV-1.
Related JoVE Video
Intestinal protozoan infections in the immunocompromised host.
Curr. Opin. Infect. Dis.
PUBLISHED: 06-29-2013
Show Abstract
Hide Abstract
Intestinal protozoa are becoming increasingly recognized as significant pathogens in immunocompromised hosts. However, pathogenesis of infection is still poorly understood, diagnostic tests remain insensitive, and management continues to pose a challenge.
Related JoVE Video
Human T-lymphotropic virus type 1 infection is frequent in rural communities of the southern Andes of Peru.
Int. J. Infect. Dis.
PUBLISHED: 06-06-2013
Show Abstract
Hide Abstract
To evaluate the presence of human T-lymphotropic virus type 1 (HTLV-1) infection in isolated rural communities in the southern Andes of Peru.
Related JoVE Video
Staphylococcus aureus causing tropical pyomyositis, Amazon Basin, Peru.
Emerging Infect. Dis.
PUBLISHED: 06-05-2013
Show Abstract
Hide Abstract
We studied 12 Staphylococcus aureus isolates causing tropical pyomyositis in the Amazon Basin of Peru. All isolates were methicillin-susceptible; 11 carried Panton-Valentine leukocidin-encoding genes, and 5 belonged to multilocus sequence type 25 and possessed an extensive set of enterotoxins. Our findings suggest sequence type 25 is circulating in tropical areas of South America.
Related JoVE Video
Strongyloidiasis and infective dermatitis alter human T lymphotropic virus-1 clonality in vivo.
PLoS Pathog.
PUBLISHED: 04-01-2013
Show Abstract
Hide Abstract
Human T-lymphotropic Virus-1 (HTLV-1) is a retrovirus that persists lifelong by driving clonal proliferation of infected T-cells. HTLV-1 causes a neuroinflammatory disease and adult T-cell leukemia/lymphoma. Strongyloidiasis, a gastrointestinal infection by the helminth Strongyloides stercoralis, and Infective Dermatitis associated with HTLV-1 (IDH), appear to be risk factors for the development of HTLV-1 related diseases. We used high-throughput sequencing to map and quantify the insertion sites of the provirus in order to monitor the clonality of the HTLV-1-infected T-cell population (i.e. the number of distinct clones and abundance of each clone). A newly developed biodiversity estimator called "DivE" was used to estimate the total number of clones in the blood. We found that the major determinant of proviral load in all subjects without leukemia/lymphoma was the total number of HTLV-1-infected clones. Nevertheless, the significantly higher proviral load in patients with strongyloidiasis or IDH was due to an increase in the mean clone abundance, not to an increase in the number of infected clones. These patients appear to be less capable of restricting clone abundance than those with HTLV-1 alone. In patients co-infected with Strongyloides there was an increased degree of oligoclonal expansion and a higher rate of turnover (i.e. appearance and disappearance) of HTLV-1-infected clones. In Strongyloides co-infected patients and those with IDH, proliferation of the most abundant HTLV-1? T-cell clones is independent of the genomic environment of the provirus, in sharp contrast to patients with HTLV-1 infection alone. This implies that new selection forces are driving oligoclonal proliferation in Strongyloides co-infection and IDH. We conclude that strongyloidiasis and IDH increase the risk of development of HTLV-1-associated diseases by increasing the rate of infection of new clones and the abundance of existing HTLV-1? clones.
Related JoVE Video
Histopathological features of tungiasis in Peru.
Am. J. Trop. Med. Hyg.
PUBLISHED: 03-11-2013
Show Abstract
Hide Abstract
Tungiasis is an ectoparasitic skin disease caused by Tunga penetrans and Tunga trimamillata. There is a lack of histopathological studies that evaluate the recognition of this flea in tissues. We describe the ex vivo dermoscopic and the histopathological patterns of six cases and relate the findings to the developmental stage of the parasite as defined by the Fortaleza classification: two were classified as Fortaleza 3b, 3 as 4a, and 1 as 4b. Two dermoscopic patterns were observed: a brown pigmented ring and a radial crown with a central pore. The most common histopathological findings were an eosinophilic cuticle, eggs in different stages of development, tracheal rings (parasite), and basal hyperplasia (host). The eosinophilic cuticle, eggs in different stages of evolution, and tracheal rings can help to establish the diagnosis when other parts of the parasite are lacking. The Fortaleza staging may represent a tool for pathology reporting purposes.
Related JoVE Video
The validity of cerebrospinal fluid parameters for the diagnosis of tuberculous meningitis.
Int. J. Infect. Dis.
PUBLISHED: 02-18-2013
Show Abstract
Hide Abstract
To assess the diagnostic validity of laboratory cerebrospinal fluid (CSF) parameters for discriminating between tuberculous meningitis (TBM) and other causes of meningeal syndrome in high tuberculosis incidence settings.
Related JoVE Video
A foodborne outbreak of brucellosis at a police station cafeteria, Lima, Peru.
Am. J. Trop. Med. Hyg.
PUBLISHED: 02-04-2013
Show Abstract
Hide Abstract
Brucella melitensis is highly infectious for humans and can be transmitted to humans in a number of epidemiological contexts. Within the context of an ongoing brucellosis surveillance project, an outbreak at a Peruvian police officer cafeteria was discovered, which led to active surveillance (serology, blood culture) for additional cases among 49 police officers who had also eaten there. The cohort was followed up to 18 months regardless of treatment or symptoms. Active surveillance estimated the attack rate at 26.5% (13 of 49). Blood cultures from four cases were positive; these isolates were indistinguishable using multiple locus variable number tandem repeat analysis. This investigation indicates the importance of case tracking and active surveillance for brucellosis in the context of potential common source exposure. These results provide rationale for public health investigations of brucellosis index cases including the bioterrorism-related dissemination of Brucella.
Related JoVE Video
The laboratory diagnosis and follow up of strongyloidiasis: a systematic review.
PLoS Negl Trop Dis
PUBLISHED: 01-17-2013
Show Abstract
Hide Abstract
Strongyloidiasis is frequently under diagnosed since many infections remain asymptomatic and conventional diagnostic tests based on parasitological examination are not sufficiently sensitive. Serology is useful but is still only available in reference laboratories. The need for improved diagnostic tests in terms of sensitivity and specificity is clear, particularly in immunocompromised patients or candidates to immunosuppressive treatments. This review aims to evaluate both conventional and novel techniques for the diagnosis of strongyloidiasis as well as available cure markers for this parasitic infection.
Related JoVE Video
Medication possession ratio predicts antiretroviral regimens persistence in Peru.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
In developing nations, the use of operational parameters (OPs) in the prediction of clinical care represents a missed opportunity to enhance the care process. We modeled the impact of multiple measurements of antiretroviral treatment (ART) adherence on antiretroviral treatment outcomes in Peru.
Related JoVE Video
Induced sputum MMP-1, -3 & -8 concentrations during treatment of tuberculosis.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Tuberculosis (TB) destroys lung tissues and this immunopathology is mediated in part by Matrix Metalloproteinases (MMPs). There are no data on the relationship between local tissue MMPs concentrations, anti-tuberculosis therapy and sputum conversion.
Related JoVE Video
Bronchiectasis is associated with human T-lymphotropic virus 1 infection in an Indigenous Australian population.
Clin. Infect. Dis.
PUBLISHED: 11-17-2011
Show Abstract
Hide Abstract
Recent studies suggest that infection with human T-lymphotropic virus 1 (HTLV-1) might be associated with bronchiectasis among Indigenous Australians. The present study compared the clinical characteristics and outcomes of bronchiectasis in this population, according to HTLV-1 serologic status.
Related JoVE Video
Systems biology approach predicts antibody signature associated with Brucella melitensis infection in humans.
J. Proteome Res.
PUBLISHED: 09-08-2011
Show Abstract
Hide Abstract
A complete understanding of the factors that determine selection of antigens recognized by the humoral immune response following infectious agent challenge is lacking. Here we illustrate a systems biology approach to identify the antibody signature associated with Brucella melitensis (Bm) infection in humans and predict proteomic features of serodiagnostic antigens. By taking advantage of a full proteome microarray expressing previously cloned 1406 and newly cloned 1640 Bm genes, we were able to identify 122 immunodominant antigens and 33 serodiagnostic antigens. The reactive antigens were then classified according to annotated functional features (COGs), computationally predicted features (e.g., subcellular localization, physical properties), and protein expression estimated by mass spectrometry (MS). Enrichment analyses indicated that membrane association and secretion were significant enriching features of the reactive antigens, as were proteins predicted to have a signal peptide, a single transmembrane domain, and outer membrane or periplasmic location. These features accounted for 67% of the serodiagnostic antigens. An overlay of the seroreactive antigen set with proteomic data sets generated by MS identified an additional 24%, suggesting that protein expression in bacteria is an additional determinant in the induction of Brucella-specific antibodies. This analysis indicates that one-third of the proteome contains enriching features that account for 91% of the antigens recognized, and after B. melitensis infection the immune system develops significant antibody titers against 10% of the proteins with these enriching features. This systems biology approach provides an empirical basis for understanding the breadth and specificity of the immune response to B. melitensis and a new framework for comparing the humoral responses against other microorganisms.
Related JoVE Video
[Seroprevalence of leptospirosis in Puente Piedra, Lima, in 2006].
Rev Peru Med Exp Salud Publica
PUBLISHED: 08-17-2011
Show Abstract
Hide Abstract
Leptospirosis is a disease widely prevalent in tropical areas, but may also be present in urban areas. The present study aims to determine the seroprevalence of Leptospira in the district of Puente Piedra, where there have been cases of severe leptospirosis in recent years. We collected data related to risk factors associated with leptospirosis and blood samples from 250 participants, selected by random sampling. We found a high prevalence of risk factors in the population and using the microscopic agglutination test, antibodies were found in only 3 participants (1.2%).
Related JoVE Video
High prevalence of primary multidrug resistant tuberculosis in persons with no known risk factors.
PLoS ONE
PUBLISHED: 06-10-2011
Show Abstract
Hide Abstract
In high multidrug resistant (MDR) tuberculosis (TB) prevalence areas, drug susceptibility testing (DST) at diagnosis is recommended for patients with risk factors for MDR. However, this approach might miss a substantial proportion of MDR-TB in the general population. We studied primary MDR in patients considered to be at low risk of MDR-TB in Lima, Peru.
Related JoVE Video
Zoonoses and marginalised infectious diseases of poverty: where do we stand?
Parasit Vectors
PUBLISHED: 06-07-2011
Show Abstract
Hide Abstract
Despite growing awareness of the importance of controlling neglected tropical diseases as a contribution to poverty alleviation and achieving the Millennium Development Goals, there is a need to up-scale programmes to achieve wider public health benefits. This implementation deficit is attributable to several factors but one often overlooked is the specific difficulty in tackling diseases that involve both people and animals - the zoonoses. A Disease Reference Group on Zoonoses and Marginalised Infectious Diseases (DRG6) was convened by the Special Programme for Research and Training in Tropical Diseases (TDR), a programme executed by the World Health Organization and co-sponsored by UNICEF, UNDP, the World Bank and WHO. The key considerations included: (a) the general lack of reliable quantitative data on their public health burden; (b) the need to evaluate livestock production losses and their additional impacts on health and poverty; (c) the relevance of cross-sectoral issues essential to designing and implementing public health interventions for zoonotic diseases; and (d) identifying priority areas for research and interventions to harness resources most effectively. Beyond disease specific research issues, a set of common macro-priorities and interventions were identified which, if implemented through a more integrated approach by countries, would have a significant impact on human health of the most marginalised populations characteristically dependent on livestock.
Related JoVE Video
Knowledge, attitudes and practice survey about antimicrobial resistance and prescribing among physicians in a hospital setting in Lima, Peru.
BMC Clin Pharmacol
PUBLISHED: 05-09-2011
Show Abstract
Hide Abstract
Misuse of antimicrobials (AMs) and antimicrobial resistance (AMR) are global concerns. The present study evaluated knowledge, attitudes and practices about AMR and AM prescribing among medical doctors in two large public hospitals in Lima, Peru, a middle-income country.
Related JoVE Video
Short communication an interferon-? ELISPOT assay with two cytotoxic T cell epitopes derived from HTLV-1 tax region 161-233 discriminates HTLV-1-associated myelopathy/tropical spastic paraparesis patients from asymptomatic HTLV-1 carriers in a Peruvian po
AIDS Res. Hum. Retroviruses
PUBLISHED: 05-09-2011
Show Abstract
Hide Abstract
HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic and progressive disorder caused by the human T-lymphotropic virus type 1 (HTLV-1). In HTLV-1 infection, a strong cytotoxic T cell (CTL) response is mounted against the immunodominant protein Tax. Previous studies carried out by our group reported that increased IFN-? enzyme-linked immunospot (ELISPOT) responses against the region spanning amino acids 161 to 233 of the Tax protein were associated with HAM/TSP and increased HTLV-1 proviral load (PVL). An exploratory study was conducted on 16 subjects with HAM/TSP, 13 asymptomatic carriers (AC), and 10 HTLV-1-seronegative controls (SC) to map the HAM/TSP-associated CTL epitopes within Tax region 161-233. The PVL of the infected subjects was determined and the specific CTL response was evaluated with a 6-h incubation IFN-? ELISPOT assay using peripheral blood mononuclear cells (PBMCs) stimulated with 16 individual overlapping peptides covering the Tax region 161-233. Other proinflammatory and Th1/Th2 cytokines were also quantified in the supernatants by a flow cytometry multiplex assay. In addition, a set of human leukocyte antigen (HLA) class I alleles that bind with high affinity to the CTL epitopes of interest was determined using computational tools. Univariate analyses identified an association between ELISPOT responses to two new CTL epitopes, Tax 173-185 and Tax 181-193, and the presence of HAM/TSP as well as an increased PVL. The HLA-A*6801 allele, which is predicted to bind to the Tax 181-193 peptide, was overpresented in the HAM/TSP patients tested.
Related JoVE Video
Evidence of tungiasis in pre-Hispanic America.
Emerging Infect. Dis.
PUBLISHED: 05-03-2011
Show Abstract
Hide Abstract
Ancient parasites of the genus Tunga originated in America and, during the first half of the 19th century, were transported to the Eastern Hemisphere on transatlantic voyages. Although they were first documented by Spanish chroniclers after the arrival of Columbus, little is known about their presence in pre-Hispanic America. To evaluate the antiquity of tungiasis in America, we assessed several kinds of early documentation, including written evidence and pre-Incan earthenware reproductions. We identified 17 written documents and 4 anthropomorphic figures, of which 3 originated from the Chimu culture and 1 from the Maranga culture. Tungiasis has been endemic to Peru for at least 14 centuries. We also identified a pottery fragment during this study. This fragment is the fourth representation of tungiasis in pre-Hispanic America identified and provides explicit evidence of disease endemicity in ancient Peru.
Related JoVE Video
Feasibility, diagnostic accuracy, and effectiveness of decentralised use of the Xpert MTB/RIF test for diagnosis of tuberculosis and multidrug resistance: a multicentre implementation study.
Lancet
PUBLISHED: 04-18-2011
Show Abstract
Hide Abstract
The Xpert MTB/RIF test (Cepheid, Sunnyvale, CA, USA) can detect tuberculosis and its multidrug-resistant form with very high sensitivity and specificity in controlled studies, but no performance data exist from district and subdistrict health facilities in tuberculosis-endemic countries. We aimed to assess operational feasibility, accuracy, and effectiveness of implementation in such settings.
Related JoVE Video
Balamuthia mandrillaris infection of the skin and central nervous system: an emerging disease of concern to many specialties in medicine.
Curr. Opin. Infect. Dis.
PUBLISHED: 04-07-2011
Show Abstract
Hide Abstract
Balamuthia mandrillaris infection of the skin and central nervous system has been increasingly reported in the last decade, making this entity a genuine emerging disease. The ability of the clinician in recognizing the skin lesion early in the course of the disease may lead to a successful therapeutic intervention in an otherwise fatal disease.
Related JoVE Video
Self-reported risks for multiple-drug resistance among new tuberculosis cases: implications for drug susceptibility screening and treatment.
PLoS ONE
PUBLISHED: 03-07-2011
Show Abstract
Hide Abstract
Multiple drug-resistance in new tuberculosis (TB) cases accounts for the majority of all multiple drug-resistant TB (MDR-TB) worldwide. Effective control requires determining which new TB patients should be tested for MDR disease, yet the effectiveness of global screening recommendations of high-risk groups is unknown.
Related JoVE Video
Enteric disease surveillance under the AFHSC-GEIS: current efforts, landscape analysis and vision forward.
BMC Public Health
PUBLISHED: 03-04-2011
Show Abstract
Hide Abstract
The mission of the Armed Forces Health Surveillance Center, Division of Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) is to support global public health and to counter infectious disease threats to the United States Armed Forces, including newly identified agents or those increasing in incidence. Enteric diseases are a growing threat to U.S. forces, which must be ready to deploy to austere environments where the risk of exposure to enteropathogens may be significant and where routine prevention efforts may be impractical. In this report, the authors review the recent activities of AFHSC-GEIS partner laboratories in regards to enteric disease surveillance, prevention and response. Each partner identified recent accomplishments, including support for regional networks. AFHSC/GEIS partners also completed a Strengths, Weaknesses, Opportunities and Threats (SWOT) survey as part of a landscape analysis of global enteric surveillance efforts. The current strengths of this network include excellent laboratory infrastructure, equipment and personnel that provide the opportunity for high-quality epidemiological studies and test platforms for point-of-care diagnostics. Weaknesses include inconsistent guidance and a splintered reporting system that hampers the comparison of data across regions or longitudinally. The newly chartered Enterics Surveillance Steering Committee (ESSC) is intended to provide clear mission guidance, a structured project review process, and central data management and analysis in support of rationally directed enteric disease surveillance efforts.
Related JoVE Video
Cross-sectional analysis of late HAART initiation in Latin America and the Caribbean: late testers and late presenters.
PLoS ONE
PUBLISHED: 03-02-2011
Show Abstract
Hide Abstract
Starting HAART in a very advanced stage of disease is assumed to be the most prevalent form of initiation in HIV-infected subjects in developing countries. Data from Latin America and the Caribbean is still lacking. Our main objective was to determine the frequency, risk factors and trends in time for being late HAART initiator (LHI) in this region.
Related JoVE Video
Update on strongyloidiasis in the immunocompromised host.
Curr Infect Dis Rep
PUBLISHED: 02-11-2011
Show Abstract
Hide Abstract
Immunocompromised persons are the most vulnerable population at risk for developing life-threatening clinical syndromes associated with strongyloidiasis, such as hyperinfection syndrome (HS) or dissemination. This review focuses on describing Strongyloides infection in the immunocompromised host, including immune response against this infection, analyzing the cases with HS published during the past 4 years in the United States, and describing the most sensitive diagnostic tools and the most effective treatment for each clinical syndrome. Strongyloidiasis is becoming an important parasitic disease in the United States, especially in the immunocompromised immigrant population. Because the transplant population is particularly at risk for developing HS, both recipients and donors should be screened for Strongyloides. Clinicians should also be aware that the development of HS can follow unexpectedly a few days after appropriate anthelminthic therapy. Highly sensitive screening tests are still not available in the major tertiary medical centers. Parenteral ivermectin has been used in some severe cases. Further therapy developments and improving diagnostic tools are warranted.
Related JoVE Video
Excessive alcohol consumption increases risk taking behaviour in travellers to Cusco, Peru.
Travel Med Infect Dis
PUBLISHED: 02-03-2011
Show Abstract
Hide Abstract
The risks associated with alcohol intoxication are rarely discussed during pre-travel counselling. However, alcohol immoderation abroad may increase the exposure to health risks. Few studies have addressed alcohol consumption and risk taking behaviour in travellers to South America. From October to December of 2004, travellers leaving the city of Cusco in Peru were asked to fill out anonymous questionnaires regarding demographics, self-reported alcohol consumption, illness and risk behaviour for sexually-transmitted infection (STI) and travellers diarrhoea. Most travellers (87.2%) consumed alcohol and 20.4% reported inebriation in Cusco. Those admitting inebriation were more likely to be male, single, <26 years old, and travelling alone or with friends. Travellers who admitted inebriation and fell ill while in Cusco were more likely to seek medical attention, change itinerary, and report decreased satisfaction with the trip experience. In the multivariate analysis, inebriation was independently associated with reporting higher numbers of unsafe food choices, illicit drug use, and risky sexual activity. It is concluded that alcohol intoxication during travel was associated with increased risk taking behaviour for common travel related conditions. Although travel related illnesses were not associated with inebriation, some markers of illness severity were more often reported by those who admitted intoxication. Risk for heavy alcohol use abroad should be assessed during the pre-travel visit in certain groups and appropriate counselling should be provided.
Related JoVE Video
Evidence-based medicine training in a resource-poor country, the importance of leveraging personal and institutional relationships.
J Eval Clin Pract
PUBLISHED: 01-30-2011
Show Abstract
Hide Abstract
Efforts to implement evidence-based medicine (EBM) training in developing countries are limited. We describe the results of an international effort to improve research capacity in a developing country; we conducted a course aimed at improving basic EBM attitudes and identified challenges.
Related JoVE Video
Cancer in HIV-infected persons from the Caribbean, Central and South America.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 01-18-2011
Show Abstract
Hide Abstract
HIV-infected individuals have heightened cancer risk. With the advent of highly active antiretroviral therapy (HAART), the frequency of some AIDS-defining cancers (ADC) has decreased although certain non-AIDS-defining cancers (NADC) are becoming more frequent. Cancers among HIV-infected individuals in Latin American and the Caribbean have not yet been carefully studied.
Related JoVE Video
Performance of an algorithm based on WHO recommendations for the diagnosis of smear-negative pulmonary tuberculosis in patients without HIV infection.
Trop. Med. Int. Health
PUBLISHED: 01-05-2011
Show Abstract
Hide Abstract
To evaluate the performance of an algorithm based on WHO recommendations for diagnosis of smear-negative pulmonary tuberculosis in HIV-negative patients.
Related JoVE Video
Treatment of methicillin-resistant Staphylococcus aureus in Latin America.
Braz J Infect Dis
PUBLISHED: 12-25-2010
Show Abstract
Hide Abstract
The global spread of methicillin-resistant Staphylococcus aureus (MRSA) means it is now a pathogen of worldwide public health concern. Within Latin America, MRSA is highly prevalent, with the proportion of S. aureus isolates that are methicillin-resistant on the rise, yet resources for managing the infection are limited. While several guidelines exist for the treatment of MRSA infections, many are written for the North American or European setting and need adaptation for use in Latin America. In this article, we aim to emphasize the importance of appropriate treatment of MRSA in the healthcare and community settings of Latin America. We present a summary of the available guidelines and antibiotics, and discuss particular considerations for clinicians treating MRSA in Latin America.
Related JoVE Video
Normalization of FoxP3(+) regulatory T cells in response to effective antiretroviral therapy.
J. Infect. Dis.
PUBLISHED: 12-21-2010
Show Abstract
Hide Abstract
Regulatory T cells (Tregs) blunt uncontrolled immune responses. In advanced human immunodeficiency virus (HIV) infection, the total number of Tregs is decreased, but the proportion of T cells with a regulatory phenotype is highly variable. We studied CD4(+)CD25(+)FoxP3(+) T cells from patients successfully treated with combination antiretroviral therapy (ART). The proportion of CD4(+)CD25(+)FoxP3(+) cells transiently increased and then decreased from a median of 13% at baseline to 5.1% at 48 weeks, similar to values in normal subjects. These data suggest that with effective therapy, the regulatory cell numbers normalize, and that the inflammatory signals driving their production may also abate.
Related JoVE Video
[Researchers training in the context of the collaborative projects: experiences of Instituto de Medicina Tropical "Alexander von Humbolt", Universidad Peruana Cayetano Heredia].
Rev Peru Med Exp Salud Publica
PUBLISHED: 12-15-2010
Show Abstract
Hide Abstract
Research is a main element for human and social development. Under this point of view, it involves particular challenges and opportunities for the so-called "developing countries". An approach for those challenges and opportunities comes from the analysis of two interrelated activities; the training of new researchers and the research development with institutions or researchers which are external to the institution ("collaborative research"). Both activities are essential for the consolidation, widening and updating of the institutional capabilities for scientific production. We present here the experiences of the Instituto de Medicina Tropical "Alexander von Humboldt" of the Universidad Peruana Cayetano Heredia, in relation to the training of new researchers, we discuss the four elements we consider key for this process; the promotion of stimulating environments for research, the proactive identification of fellows, the complementary advice and networks consolidation; and we analyze three successful models of international collaboration for the training of new researchers under different institutional approaches.
Related JoVE Video
[Treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections in Latin America].
Rev Chilena Infectol
PUBLISHED: 12-09-2010
Show Abstract
Hide Abstract
The global spread of MRSA means it is now a pathogen of worldwide public health concern. Within Latin America, MRSA is highly prevalent, with the proportion of S. aureus isolates that are methicillin-resistant on the rise, yet resources for managing the infection are limited. While several guidelines exist for the treatment of MRSA infections, many are written for the North American or European setting and need adaptation for use in Latin America. In this article, we aim to emphasize the importance of appropriate treatment of MRSA in the healthcare and community settings of Latin America. We present a summary of the available guidelines and antibiotics, and discuss particular considerations for clinicians treating MRSA in Latin America.
Related JoVE Video
Pre-travel preparation for Cusco, Peru: a comparison between European and North American travelers.
J Travel Med
PUBLISHED: 11-06-2010
Show Abstract
Hide Abstract
Demographics, preferences on health care, and regional differences in pre-travel advice guidelines may influence the preparation of travelers to developing countries.
Related JoVE Video
Research training needs in Peruvian national TB/HIV programs.
BMC Med Educ
PUBLISHED: 09-28-2010
Show Abstract
Hide Abstract
There are few published reports of research training needs assessments and research training programs. In an effort to expand this nascent field of study and to bridge the gap between research and practice, we sought to systematically assess the research training needs of health care professionals working at Peruvian governmental institutions leading HIV and tuberculosis (TB) control and among senior stakeholders in the field.
Related JoVE Video
Rapid molecular detection of tuberculosis and rifampin resistance.
N. Engl. J. Med.
PUBLISHED: 09-10-2010
Show Abstract
Hide Abstract
Global control of tuberculosis is hampered by slow, insensitive diagnostic methods, particularly for the detection of drug-resistant forms and in patients with human immunodeficiency virus infection. Early detection is essential to reduce the death rate and interrupt transmission, but the complexity and infrastructure needs of sensitive methods limit their accessibility and effect.
Related JoVE Video
Mechanisms of liver fibrosis associated with experimental Fasciola hepatica infection: roles of Fas2 proteinase and hepatic stellate cell activation.
J. Parasitol.
PUBLISHED: 09-09-2010
Show Abstract
Hide Abstract
We have evaluated the possible mechanisms of liver fibrosis caused by Fasciola hepatica in an animal model and in culture using immortalized human stellate cells. Liver biopsies of F. hepatica-infected rats were performed at wk 8 and 16. Serum-starved LX-2 cells, a human stellate cell line, were exposed to increasing concentrations of Fas2 antigen. The expression of key fibrosis-related genes was evaluated by qRT-PCR. There was a significant correlation between fibrogenic gene expression and both intensity and duration of infection. LX-2 cells exposed to Fas2 showed progressively increased expression of mRNAs for Collagen I, alpha-smooth muscle-actin, platelet-derived growth factor beta receptor, and tissue inhibitor of metalloproteinase II; inhibition of Fas2 cysteine proteinase activity by E-64 abrogated these increases, suggesting that the protease activity of Fas2 is involved in fibrogenic stimulation. In summary, F. hepatica infection is associated with up-regulation of mRNAs associated with hepatic fibrogenesis in vivo and in activated hepatic stellate cells.
Related JoVE Video
Human herpesvirus 8 genotype E in patients with Kaposi sarcoma, Peru.
Emerging Infect. Dis.
PUBLISHED: 08-26-2010
Show Abstract
Hide Abstract
To determine human herpesvirus 8 (HHV-8) K1 genotypes in patients with Kaposi sarcoma (KS) from Peru, we characterized HHV-8 in 25 KS biopsy samples. Our findings of 8 A, 1 B, 14 C, and 2 E subtypes showed high HHV-8 diversity in these patients and association between E genotype and KS development.
Related JoVE Video
Arboviral etiologies of acute febrile illnesses in Western South America, 2000-2007.
PLoS Negl Trop Dis
PUBLISHED: 07-12-2010
Show Abstract
Hide Abstract
Arthropod-borne viruses (arboviruses) are among the most common agents of human febrile illness worldwide and the most important emerging pathogens, causing multiple notable epidemics of human disease over recent decades. Despite the public health relevance, little is know about the geographic distribution, relative impact, and risk factors for arbovirus infection in many regions of the world. Our objectives were to describe the arboviruses associated with acute undifferentiated febrile illness in participating clinics in four countries in South America and to provide detailed epidemiological analysis of arbovirus infection in Iquitos, Peru, where more extensive monitoring was conducted.
Related JoVE Video
Clinical prediction rule for stratifying risk of pulmonary multidrug-resistant tuberculosis.
PLoS ONE
PUBLISHED: 06-25-2010
Show Abstract
Hide Abstract
Multidrug-resistant tuberculosis (MDR-TB), resistance to at least isoniazid and rifampin, is a worldwide problem.
Related JoVE Video
Successful treatment of Balamuthia mandrillaris amoebic infection with extensive neurological and cutaneous involvement.
Clin. Infect. Dis.
PUBLISHED: 06-17-2010
Show Abstract
Hide Abstract
Granulomatous amoebic encephalitis caused by Balamuthia mandrillaris is an uncommon infection for which there is no optimal therapy. We describe a young, female patient who presented with extensive cutaneous and neurological involvement and who recovered after receiving prolonged treatment with miltefosine, fluconazole, and albendazole.
Related JoVE Video
An ectopic case of Tunga spp. infection in Peru.
Am. J. Trop. Med. Hyg.
PUBLISHED: 06-04-2010
Show Abstract
Hide Abstract
Tungiasis is a neglected ectoparasitism of impoverished areas in South America and sub-Saharan Africa. The sand flea Tunga spp. preferably infests the soles and the periungueal and interdigital regions of the feet. Ectopic tungiasis is rare, even in highly endemic areas. We describe a case of an indigenous patient in Peru who presented with a nodular lesion in the extensor aspect of the knee and whose biopsy was compatible with Tunga spp. This is the first documented case of knee tungiasis in an endemic country. The historical, clinical, histological, and current epidemiological aspects of tungiasis in Peru are discussed here.
Related JoVE Video
Rates and reasons for early change of first HAART in HIV-1-infected patients in 7 sites throughout the Caribbean and Latin America.
PLoS ONE
PUBLISHED: 04-02-2010
Show Abstract
Hide Abstract
HAART rollout in Latin America and the Caribbean has increased from approximately 210,000 in 2003 to 390,000 patients in 2007, covering 62% (51%-70%) of eligible patients, with considerable variation among countries. No multi-cohort study has examined rates of and reasons for change of initial HAART in this region.
Related JoVE Video
Large scale immune profiling of infected humans and goats reveals differential recognition of Brucella melitensis antigens.
PLoS Negl Trop Dis
PUBLISHED: 03-19-2010
Show Abstract
Hide Abstract
Brucellosis is a widespread zoonotic disease that is also a potential agent of bioterrorism. Current serological assays to diagnose human brucellosis in clinical settings are based on detection of agglutinating anti-LPS antibodies. To better understand the universe of antibody responses that develop after B. melitensis infection, a protein microarray was fabricated containing 1,406 predicted B. melitensis proteins. The array was probed with sera from experimentally infected goats and naturally infected humans from an endemic region in Peru. The assay identified 18 antigens differentially recognized by infected and non-infected goats, and 13 serodiagnostic antigens that differentiate human patients proven to have acute brucellosis from syndromically similar patients. There were 31 cross-reactive antigens in healthy goats and 20 cross-reactive antigens in healthy humans. Only two of the serodiagnostic antigens and eight of the cross-reactive antigens overlap between humans and goats. Based on these results, a nitrocellulose line blot containing the human serodiagnostic antigens was fabricated and applied in a simple assay that validated the accuracy of the protein microarray results in the diagnosis of humans. These data demonstrate that an experimentally infected natural reservoir host produces a fundamentally different immune response than a naturally infected accidental human host.
Related JoVE Video
Venezuelan equine encephalitis and 2 human deaths, Peru.
Emerging Infect. Dis.
PUBLISHED: 03-06-2010
Show Abstract
Hide Abstract
Studies have suggested that enzootic strains of Venezuelan equine encephalitis (VEE) subtype ID in the Amazon region, Peru, may be less pathogenic to humans than are epizootic variants. Deaths of 2 persons with evidence of acute VEE virus infection indicate that fatal VEEV infection in Peru is likely. Cases may remain underreported.
Related JoVE Video
Asymptomatic renal colonization of humans in the peruvian Amazon by Leptospira.
PLoS Negl Trop Dis
PUBLISHED: 02-23-2010
Show Abstract
Hide Abstract
Renal carriage and shedding of leptospires is characteristic of carrier or maintenance animal hosts. Sporadic reports indicate that after infection, humans may excrete leptospires for extended periods. We hypothesized that, like mammalian reservoir hosts, humans develop asymptomatic leptospiruria in settings of high disease transmission such as the Peruvian Amazon.
Related JoVE Video
Durability of initial antiretroviral therapy in a resource-constrained setting and the potential need for zidovudine weight-based dosing.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 01-28-2010
Show Abstract
Hide Abstract
Whereas access to antiretroviral therapy (ART) for HIV-infected individuals in the developing world is increasing, data on factors impacting initial regimen durability are lacking.
Related JoVE Video
Role of killer cell immunoglobulin-like receptor gene content and human leukocyte antigen-C group in susceptibility to human T-lymphotropic virus 1-associated myelopathy/tropical spastic paraparesis in Peru.
Hum. Immunol.
PUBLISHED: 01-23-2010
Show Abstract
Hide Abstract
Human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) affects approximately 5% of HTLV-1-infected individuals. It is poorly understood why only some infected subjects develop this disease, but host genetic factors may determine susceptibility. The innate immune system may influence disease outcome in HTLV-1-infected individuals because of its role in early immune responses to viral infections. Variation in genes encoding killer cell immunoglobulin-like receptors (KIR) and their human leukocyte antigen (HLA) molecule ligands may affect the risk of HAM/TSP. We performed a two-stage case-control study to examine the distribution of KIR genes and HLA-Cw groups in Peruvian HTLV-1-infected HAM/TSP individuals and asymptomatic carriers. We also tested for epistatic effects between specific KIR genes and HLA-Cw groups. In the first stage, we found several trends toward association with HAM/TSP or proviral load (PVL). However, these results were not replicated in the second stage. In conclusion, this is the first report on KIR gene frequencies in the Peruvian population and may be of significance in hematopoietic stem-cell transplants. Our study did not reveal significant associations between KIR genes and HLA-Cw groups and HAM/TSP or PVL. However, because our study was powered to detect only larger effects, additional studies using larger cohorts are needed.
Related JoVE Video
Evaluation of host genetic and viral factors as surrogate markers for HTLV-1-associated myelopathy/tropical spastic paraparesis in Peruvian HTLV-1-infected patients.
J. Med. Virol.
PUBLISHED: 01-21-2010
Show Abstract
Hide Abstract
Human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a complication that affects up to 5% of HTLV-1-infected individuals. Several host genetic and viral factors have been associated with the risk of HAM/TSP. The aim of this study was to evaluate the performance of a prognostic model for HAM/TSP developed in Japan in a Peruvian population of 71 HAM/TSP patients and 94 asymptomatic carriers (ACs). This model included age, proviral load (PVL), the presence of HLA-A*02 and HLA-Cw*08 alleles, SDF-1 +801, and TNF-alpha -863 polymorphisms, and viral subgroup. We describe frequencies for the four host genetic markers and demonstrate the presence of the HTLV-1 tax B subgroup in Peru. Using cross-validation, we show that the predictive ability of the prognostic model, as characterized by the area under the receiver-operating characteristic curve (AUC), does not differ from a model containing PVL only (both AUC = 0.74). We found some suggestive evidence of a protective effect of the HLA-A*02 allele but failed to replicate the associations with the other three genetic markers and with viral subgroup. A logistic model containing PVL, age, gender, and HLA-A*02 provided the best predictive ability in the Peruvian cohort (AUC = 0.79). J. Med. Virol. 82:460-466, 2010. (c) 2010 Wiley-Liss, Inc.
Related JoVE Video
Evolution of methicillin-resistant Staphylococcus aureus clones in Latin America.
Int. J. Infect. Dis.
PUBLISHED: 01-03-2010
Show Abstract
Hide Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a prominent nosocomial bacterial pathogen, associated with significant morbidity and mortality. The global incidence is increasing, and Latin America is no exception. This article reviews MRSA clonal distribution in Latin America and implications for clinical practice.
Related JoVE Video
Characterization of small ColE-like plasmids mediating widespread dissemination of the qnrB19 gene in commensal enterobacteria.
Antimicrob. Agents Chemother.
PUBLISHED: 12-14-2009
Show Abstract
Hide Abstract
In this work, we have characterized two small ColE-like plasmids (pECY6-7, 2.7 kb in size, and pECC14-9, of 3.0 kb), encoding the QnrB19 quinolone resistance determinant, that were carried by several clonally unrelated quinolone-resistant commensal Escherichia coli strains isolated from healthy children living in different urban areas of Peru and Bolivia. The two plasmids are closely related to each other and carry the qnrB19 gene as the sole resistance determinant, located in a conserved genetic context between the plasmid RNAII sequence (which controls plasmid replication) and the plasmid Xer site (involved in plasmid dimer resolution). ISEcp1-like or other putative insertion sequences are not present in the qnrB19-flanking regions or elsewhere on the plasmids. Since we previously observed a high prevalence (54%) of qnrB genes in the metagenomes of commensal enterobacteria from the same population of healthy children, the presence of pECY6-7- and pECC14-9-like plasmids in those qnrB-positive metagenomes was investigated by PCR mapping. Both plasmids were found to be highly prevalent (67% and 16%, respectively) in the qnrB-positive metagenomes, suggesting that dissemination of these small plasmids played a major role in the widespread dissemination of qnrB genes observed in commensal enterobacteria from healthy children living in those areas.
Related JoVE Video
[Parasite intestinal infection and factors associated with coccidian infection in adults at public hospital in Lima, Peru].
Rev Chilena Infectol
PUBLISHED: 11-09-2009
Show Abstract
Hide Abstract
To evaluate the frequency of intestinal parasites and risk factors associated with coccidian infection in patients cared for at a public hospital in Lima-Peru.
Related JoVE Video
High prevalence of sexually transmitted infections among young Peruvians who have sexual intercourse with foreign travelers in Cuzco.
J Travel Med
PUBLISHED: 10-03-2009
Show Abstract
Hide Abstract
Sexual networking in popular tourist destinations is a problem worldwide. In Peru, locals sexually interacting with travelers bridge high-risk groups, the general population, and travelers.
Related JoVE Video
Development and validation of a multiplex real-time PCR assay for simultaneous genotyping and human T-lymphotropic virus type 1, 2, and 3 proviral load determination.
J. Clin. Microbiol.
PUBLISHED: 09-09-2009
Show Abstract
Hide Abstract
The human T-lymphotropic virus (HTLV) proviral load remains the best surrogate marker for disease progression. Real-time PCR techniques have been developed for detection and quantification of cosmopolitan HTLV type 1a (HTLV-1a) and HTLV-2. Since a growing level of diversity in subtypes and genotypes is observed, we developed a multiplex quantitative PCR for simultaneous detection, genotyping, and quantification of proviral loads of HTLV-1, 2, and 3. Our assay uses tax type-specific primers and dually labeled probes and has a dynamic range of 10(5) to 10 HTLV copies. One hundred sixty-three samples were analyzed, among which all of the different subtypes within each HTLV genotype could be detected. The performance of proviral load determination of our multiplex assay was compared with that of a previously published HTLV-1 singleplex quantitative PCR based on SYBR green detection, developed at a different institute. Linear regression analysis showed a statistically significant (P < 0.0001) and strong (r(2) = 0.87) correlation between proviral load values measured with the two distinct real-time PCR assays. In conclusion, our novel assay offers an accurate molecular diagnosis and genotyping, together with the determination of the proviral load of HTLV-infected individuals, in a single amplification reaction. Moreover, our molecular assay could offer an alternative when current available serological assays are insufficient.
Related JoVE Video
Sustained antiretroviral effect of raltegravir after 96 weeks of combination therapy in treatment-naive patients with HIV-1 infection.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 08-04-2009
Show Abstract
Hide Abstract
The purpose of this study was to evaluate the safety and efficacy of raltegravir vs efavirenz-based antiretroviral therapy after 96 weeks in treatment-naive patients with HIV-1 infection.
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.