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The increased availability of quality genomic data has greatly improved the scope and resolution of our understanding of the recent evolutionary history of wild species adapted to extreme environments and their susceptibility to anthropogenic impacts. The guanaco (Lama guanicoe), the largest wild ungulate in South America, is a good example. The guanaco is well adapted to a wide range of habitats, including the Sechura Desert, the high Andes Mountains to the north, and the extreme temperatures and conditions of Navarino Island to the south. Guanacos also have a long history of overexploitation by humans. To assess the evolutionary impact of these challenging habitats on the genomic diversity, we analyzed 38 genomes (â¼10 to 16×) throughout their extensive latitudinal distribution from the Sechura and Atacama Desert to southward into Tierra del Fuego Island. These included analyses of patterns of unique differentiation in the north and geographic region further south with admixture among L. g. cacsilensis and L. g. guanicoe. Our findings provide new insights on the divergence of the subspecies â¼800,000 yr BP and document two divergent demographic trajectories and to the initial expansion of guanaco into the more southern portions of the Atacama Desert. Patagonian guanacos have experienced contemporary reductions in effective population sizes, likely the consequence of anthropogenic impacts. The lowest levels of genetic diversity corresponded to their northern and western limits of distribution and some varying degrees of genetic differentiation. Adaptive genomic diversity was strongly linked with environmental variables and was linked with colonization toward the south followed by adaptation.
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Camelídeos Americanos , Animais , Camelídeos Americanos/genética , Ecossistema , Clima Desértico , Adaptação Fisiológica/genética , Genoma , Variação Genética , Regiões Antárticas , América do Sul , Evolução MolecularRESUMO
The remarkable radiation of South American (SA) canids produced 10 extant species distributed across diverse habitats, including disparate forms such as the short-legged, hypercarnivorous bush dog and the long-legged, largely frugivorous maned wolf. Despite considerable research spanning nearly two centuries, many aspects of their evolutionary history remain unknown. Here, we analyzed 31 whole genomes encompassing all extant SA canid species to assess phylogenetic relationships, interspecific hybridization, historical demography, current genetic diversity, and the molecular bases of adaptations in the bush dog and maned wolf. We found that SA canids originated from a single ancestor that colonized South America 3.9 to 3.5 Mya, followed by diversification east of the Andes and then a single colonization event and radiation of Lycalopex species west of the Andes. We detected extensive historical gene flow between recently diverged lineages and observed distinct patterns of genomic diversity and demographic history in SA canids, likely induced by past climatic cycles compounded by human-induced population declines. Genome-wide scans of selection showed that disparate limb proportions in the bush dog and maned wolf may derive from mutations in genes regulating chondrocyte proliferation and enlargement. Further, frugivory in the maned wolf may have been enabled by variants in genes associated with energy intake from short-chain fatty acids. In contrast, unique genetic variants detected in the bush dog may underlie interdigital webbing and dental adaptations for hypercarnivory. Our analyses shed light on the evolution of a unique carnivoran radiation and how it was shaped by South American topography and climate change.
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Adaptação Fisiológica , Canidae , Filogenia , Adaptação Fisiológica/genética , Animais , Canidae/classificação , Canidae/genética , Demografia , Variação Genética , Genômica , América do SulRESUMO
Ecological differentiation among diverging species is an important component of the evolutionary process and can be investigated in rapid and recent radiations. Here, we use whole genome sequences of five species from the genus Leopardus, a recently diversified Neotropical lineage with species bearing distinctive morphological, ecological, and behavioral features, to investigate genome-wide diversity, comparative demographic history and signatures of positive selection. Our results show that divergent ecological strategies are reflected in genomic features, for example a generalist species shows historically larger effective population size and higher heterozygosity than habitat specialists. The demographic history of these cats seems to have been jointly driven by climate fluctuations and habitat specialization, with different ecological adaptations leading to distinct trajectories. Finally, a gene involved in vertebrate retinal neurogenesis (POU4F2) was found to be under positive selection in the margay, a cat with notoriously large eyes that are likely associated with its nocturnal and arboreal specializations.
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Ecossistema , Genoma , Evolução Biológica , Genômica , Filogenia , Densidade DemográficaRESUMO
Human transformation of natural habitats facilitates pathogen transmission between domestic and wild species. The guigna (Leopardus guigna), a small felid found in Chile, has experienced habitat loss and an increased probability of contact with domestic cats. Here, we describe the interspecific transmission of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) between domestic cats and guignas and assess its correlation with human landscape perturbation. Blood and tissue samples from 102 free-ranging guignas and 262 domestic cats were collected and analyzed by PCR and sequencing. Guigna and domestic cat FeLV and FIV prevalence were very similar. Phylogenetic analysis showed guigna FeLV and FIV sequences are positioned within worldwide domestic cat virus clades with high nucleotide similarity. Guigna FeLV infection was significantly associated with fragmented landscapes with resident domestic cats. There was little evidence of clinical signs of disease in guignas. Our results contribute to the understanding of the implications of landscape perturbation and emerging diseases.
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Extensive livestock production and urbanization entail modifications of natural landscapes, including installation of fences, development of agriculture, urbanization of natural areas, and construction of roads and infrastructure that, together, impact native fauna. Here, we evaluate the diversity and genetic structure of endemic guanacos (Lama guanicoe) of the Monte and Patagonian Steppe of central Argentina, which have been reduced and displaced by sheep ranching and other impacts of human activities. Analyses of genetic variation of microsatellite loci and d-loop revealed high levels of genetic variation and latitudinal segregation of mitochondrial haplotypes. There were indications of at least two historical populations in the Monte and the Patagonian Steppe based on shared haplotypes and shared demographic history among localities. Currently, guanacos are structured into three groups that were probably reconnected relatively recently, possibly facilitated by a reduction of sheep and livestock in recent decades and a recovery of the guanaco populations. These results provide evidence of the genetic effects of livestock activity and urbanization on wild herbivore populations, which were possibly exacerbated by an arid environment with limited productive areas. The results highlight the importance of enacting conservation management plans to ensure the persistence of ancestral and ecologically functional populations of guanacos.
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A molecular genetic protocol for distinguishing pure and hybrid South American camelids was developed to provide strong, quantifiable, and unbiased species identification. We detail the application of the approach in the context of a criminal case in the Andes Mountains of central Chile where the defendants were alleged to have illegally hunted three wild guanacos (Lama guanicoe), as opposed to hybrid domestic llama (Lama glama)/wild guanaco crosses, which are unregulated. We describe a workflow that differentiates among wild, domestic and hybrid South American camelids (Lama versus Vicugna) based on mitochondrial cytochrome b genetic variation (to distinguish between Lama and Vicugna), and MC1R and exon 4 variation of the ASIP gene (to differentiate wild from domestic species). Additionally, we infer the population origin and sex of each of the three individuals from a panel of 15 autosomal microsatellite loci and the presence or absence of the SRY gene. Our analyses strongly supported the inference that the confiscated carcasses corresponded with 2 male and 1 female guanacos that were hunted illegally. Statistical power analyses suggested that there was an extremely low probability of misidentifying domestic camelids as wild camelids (an estimated 0 % Type I error rate), or using more conservative approached a 1.17 % chance of misidentification of wild species as domestic camelids (Type II error). Our case report and methodological and analytical protocols demonstrate the power of genetic variation in coat color genes to identify hybrids between wild and domestic camelid species and highlight the utility of the approach to help combat illegal wildlife hunting and trafficking.
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Pelo Animal , Animais Domésticos/genética , Animais Selvagens/genética , Camelidae/genética , Genética Forense/métodos , Variação Genética , Proteína Agouti Sinalizadora/genética , Animais , Conservação dos Recursos Naturais/legislação & jurisprudência , Crime/legislação & jurisprudência , Citocromos b/genética , DNA Mitocondrial/genética , Éxons , Feminino , Genes sry , Masculino , Repetições de Microssatélites , Receptor Tipo 1 de Melanocortina/genética , Análise para Determinação do Sexo , América do SulRESUMO
Pumas are the most widely distributed felid in the Western Hemisphere. Increasingly, however, human persecution and habitat loss are isolating puma populations. To explore the genomic consequences of this isolation, we assemble a draft puma genome and a geographically broad panel of resequenced individuals. We estimate that the lineage leading to present-day North American pumas diverged from South American lineages 300-100 thousand years ago. We find signatures of close inbreeding in geographically isolated North American populations, but also that tracts of homozygosity are rarely shared among these populations, suggesting that assisted gene flow would restore local genetic diversity. The genome of a Florida panther descended from translocated Central American individuals has long tracts of homozygosity despite recent outbreeding. This suggests that while translocations may introduce diversity, sustaining diversity in small and isolated populations will require either repeated translocations or restoration of landscape connectivity. Our approach provides a framework for genome-wide analyses that can be applied to the management of similarly small and isolated populations.
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Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Endogamia/métodos , Puma/genética , Animais , Fluxo Gênico , Variação Genética , Genética Populacional , Geografia , América do Norte , Filogenia , Puma/classificação , América do SulRESUMO
BACKGROUND: Leprosy is a treatable infectious disease caused by Mycobacterium leprae. However, there is additional morbidity from leprosy-associated pathologic immune reactions, reversal reaction (RR) and erythema nodosum leprosum (ENL), which occur in 1 in 3 people with leprosy, even with effective treatment of M. leprae. There is currently no predictive marker in use to indicate which people with leprosy will develop these debilitating immune reactions. Our peripheral blood mononuclear cell (PBMC) transcriptome analysis revealed that activation of the classical complement pathway is common to both RR and ENL. Additionally, differential expression of immunoglobulin receptors and B cell receptors during RR and ENL support a role for the antibody-mediated immune response during both RR and ENL. In this study, we investigated B-cell immunophenotypes, total and M. leprae-specific antibodies, and complement levels in leprosy patients with and without RR or ENL. The objective was to determine the role of these immune mediators in pathogenesis and assess their potential as biomarkers of risk for immune reactions in people with leprosy. METHODOLOGY/FINDINGS: We followed newly diagnosed leprosy cases (n = 96) for two years for development of RR or ENL. They were compared with active RR (n = 35), active ENL (n = 29), and healthy household contacts (n = 14). People with leprosy who subsequently developed ENL had increased IgM, IgG1, and C3d-associated immune complexes with decreased complement 4 (C4) at leprosy diagnosis. People who developed RR also had decreased C4 at leprosy diagnosis. Additionally, elevated anti-M. leprae antibody levels were associated with subsequent RR or ENL. CONCLUSIONS: Differential co-receptor expression and immunoglobulin levels before and during immune reactions intimate a central role for humoral immunity in RR and ENL. Decreased C4 and elevated anti-M. leprae antibodies in people with new diagnosis of leprosy may be risk factors for subsequent development of leprosy immune reactions.
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Anticorpos Antibacterianos/sangue , Complemento C3d/análise , Complemento C4/análise , Eritema Nodoso/epidemiologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Hanseníase Virchowiana/epidemiologia , Mycobacterium leprae/imunologia , Adulto , Idoso , Anticorpos Antibacterianos/imunologia , Linfócitos B/imunologia , Complemento C3d/imunologia , Complemento C4/imunologia , Eritema Nodoso/sangue , Eritema Nodoso/imunologia , Feminino , Perfilação da Expressão Gênica , Humanos , Imunidade Ativa/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Hanseníase Virchowiana/sangue , Hanseníase Virchowiana/imunologia , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
The domestication of wild vicuña and guanaco by early pre-Inca cultures is an iconic example of wildlife management and domestication in the Americas. Although domestic llamas and alpacas were clearly selected for key, yet distinct, phenotypic traits, the relative patterns and direction of selection and domestication have not been confirmed using genetic approaches. However, the detailed archaeological records from the region suggest that domestication was a process carried out under significant control and planning, which would have facilitated coordinated and thus extremely effective selective pressure to achieve and maintain desired phenotypic traits. Here we link patterns of sequence variation in two well-characterised genes coding for colour variation in vertebrates and interpret the results in the context of domestication in guanacos and vicuñas. We hypothesise that colour variation in wild populations of guanacos and vicunas were strongly selected against. In contrast, variation in coat colour variation in alpaca was strongly selected for and became rapidly fixed in alpacas. In contrast, coat colour variants in llamas were of less economic value, and thus were under less selective pressure. We report for the first time the full sequence of MC1R and 3 exons of ASIP in 171 wild specimens from throughout their distribution and which represented a range of commonly observed colour patterns. We found a significant difference in the number of non-synonymous substitutions, but not synonymous substitutions among wild and domestics species. The genetic variation in MC1R and ASIP did not differentiate alpaca from llama due to the high degree of reciprocal introgression, but the combination of 11 substitutions are sufficient to distinguish domestic from wild animals. Although there is gene flow among domestic and wild species, most of the non-synonymous variation in MC1R and ASIP was not observed in wild species, presumably because these substitutions and the associated colour phenotypes are not effectively transmitted back into wild populations. Therefore, this set of substitutions unequivocally differentiates wild from domestic animals, which will have important practical application in forensic cases involving the poaching of wild vicuñas and guanacos. These markers will also assist in identifying and studying archaeological remains pre- and post-domestication.
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BACKGROUND: Mitochondria play a key role in the balance of energy and heat production, and therefore the mitochondrial genome is under natural selection by environmental temperature and food availability, since starvation can generate more efficient coupling of energy production. However, selection over mitochondrial DNA (mtDNA) genes has usually been evaluated at the population level. We sequenced by NGS 12 mitogenomes and with four published genomes, assessed genetic variation in ten penguin species distributed from the equator to Antarctica. Signatures of selection of 13 mitochondrial protein-coding genes were evaluated by comparing among species within and among genera (Spheniscus, Pygoscelis, Eudyptula, Eudyptes and Aptenodytes). The genetic data were correlated with environmental data obtained through remote sensing (sea surface temperature [SST], chlorophyll levels [Chl] and a combination of SST and Chl [COM]) through the distribution of these species. RESULTS: We identified the complete mtDNA genomes of several penguin species, including ND6 and 8 tRNAs on the light strand and 12 protein coding genes, 14 tRNAs and two rRNAs positioned on the heavy strand. The highest diversity was found in NADH dehydrogenase genes and the lowest in COX genes. The lowest evolutionary divergence among species was between Humboldt (Spheniscus humboldti) and Galapagos (S. mendiculus) penguins (0.004), while the highest was observed between little penguin (Eudyptula minor) and Adélie penguin (Pygoscelis adeliae) (0.097). We identified a signature of purifying selection (Ka/Ks < 1) across the mitochondrial genome, which is consistent with the hypothesis that purifying selection is constraining mitogenome evolution to maintain Oxidative phosphorylation (OXPHOS) proteins and functionality. Pairwise species maximum-likelihood analyses of selection at codon sites suggest positive selection has occurred on ATP8 (Fixed-Effects Likelihood, FEL) and ND4 (Single Likelihood Ancestral Counting, SLAC) in all penguins. In contrast, COX1 had a signature of strong negative selection. ND4 Ka/Ks ratios were highly correlated with SST (Mantel, p-value: 0.0001; GLM, p-value: 0.00001) and thus may be related to climate adaptation throughout penguin speciation. CONCLUSIONS: These results identify mtDNA candidate genes under selection which could be involved in broad-scale adaptations of penguins to their environment. Such knowledge may be particularly useful for developing predictive models of how these species may respond to severe climatic changes in the future.
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Evolução Molecular , Genoma Mitocondrial , Seleção Genética , Spheniscidae/genética , Animais , DNA Mitocondrial/química , Interação Gene-Ambiente , GenômicaRESUMO
BACKGROUND: We report patient outcomes after antiretroviral therapy (ART) initiation in a network of HIV facilities in Haiti, including temporal trends and differences across clinics, during the expansion of HIV services in the country. METHODS: We assessed outcomes at 12 months after ART initiation (baseline) using routinely collected data on adults (≥15 years) in 11 HIV facilities from July 2007-December 2013. Outcomes include death (ascertained from medical records), lost to follow-up (LTF) defined as no visit > 365 days from ART initiation, and retention defined as being alive and attending care ≥ 365 days from ART initiation. Outcomes were compared across calendar year of ART initiation and across facilities. Risk factors for death and LTF were assessed using Cox proportional hazards and competing risk regression models. RESULTS: Cumulatively, 9,718 adults initiated ART with median age 37 years (IQR 30-46). Median CD4 count was 254 cells/uL (IQR 139-350). Twelve months after ART initiation, 4.4% (95% CI 4.0-4.8) of patients died, 21.7% (95% CI 20.9-22.6) were LTF, and 73.9% (95% CI 73.0-74.8) were retained in care. Twelve-month mortality decreased from 13.8% among adults who started ART in 2007 to 4.4% in 2013 (p<0.001). Twelve-month LTF after ART start was 29.2% in 2007, 18.7% in 2008, and increased to 30.1% in 2013 (p<0.001). Overall, twelve-month retention after ART start did not change over time but varied widely across facilities from 61.1% to 86.5%. CONCLUSION: Expansion of HIV services across Haiti has been successful with increasing numbers of patients initiating ART and decreasing twelve-month mortality rates. However, overall retention has not improved, despite differences across facilities, suggesting additional strategies to improve engagement in care are needed.
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Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Acessibilidade aos Serviços de Saúde , Adulto , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/mortalidade , Haiti/epidemiologia , Humanos , Perda de Seguimento , Masculino , Pessoa de Meia-Idade , Taxa de SobrevidaRESUMO
In 2003, the Haitian Study Group on Kaposi's Sarcoma and Opportunistic Infections (GHESKIO), a nonprofit organization, began administering antiretroviral therapy (ART) to its patients. This practice transformed HIV from a fatal disease to a more manageable chronic condition. However, relatively few studies focus on the experiences of survivors. This study provided a unique opportunity to interview patients who survived at least 10 years after being treated with ART at GHESKIO. The goal of the study was to elicit from patients their perspectives on what enabled them to survive with AIDS. Grounded Theory, a qualitative research method was used to guide data collection, coding, and analysis. Individual interviews were conducted, audio-taped, transcribed and analyzed in Creole, and translated into English. Data saturation was reached at 25 participants. Of which, 64% were women, the mean age was 49, range of 43-55 years, 24% were married, 44% had not completed elementary school, and 72% had no income, the remaining participants had incomes ranging from $1000 to $5000 annually. Qualitative analysis resulted in 681 codes, which were grouped into six categories: being spiritually grounded, having supportive interactions with providers, caring for children, setting personal goals, persevering and living life as usual, and maintaining strict medication adherence practices. The overarching theory was that having a reason to live despite one's circumstances and living life as usual enabled one to survive. Having a strong spiritual foundation coupled with supportive family and providers motivated participants to live and adhere to their ART. As the number of patients who are living longer with HIV in Haiti increases, results from this study will be important in helping tailor interventions that enhance their overall quality of life.
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Antirretrovirais/uso terapêutico , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Adesão à Medicação , Qualidade de Vida , Sobreviventes/psicologia , Adolescente , Adulto , Antirretrovirais/administração & dosagem , Criança , Aconselhamento , Feminino , Teoria Fundamentada , Infecções por HIV/tratamento farmacológico , Haiti , Pessoal de Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Motivação , Pesquisa Qualitativa , Apoio Social , EspiritualidadeRESUMO
To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus.
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INTRODUCTION: Adolescents account for over 40% of new HIV infections in Haiti. This analysis compares outcomes among HIV-positive adolescents before and after implementation of an adolescent HIV clinic in Port-au-Prince, Haiti. METHODS: We conducted a cohort study using programmatic data among HIV-positive adolescents aged 13 to 19. Data from 41,218 adolescents who were HIV tested from January 2003 to December 2012 were included. Outcomes across the HIV care cascade were assessed before and after implementation of an adolescent clinic (2009), including HIV testing, enrolment in care, assessment for antiretroviral therapy (ART) eligibility, ART initiation and 12-month retention. Pre-ART outcomes were assessed 12 months after HIV testing. Factors associated with pre-ART and ART attrition were identified through multivariable competing risk and Cox proportional hazards regression modelling. RESULTS: Cumulatively, 1672 (4.1%) adolescents tested HIV positive (80% female, median age 16 years). Retention by cascade step comparing pre- and post-clinic included the following: 86% versus 87% of patients enrolled in care, 61% versus 79% were assessed for ART eligibility, 85% versus 92% initiated ART and 68% versus 66% were retained 12 months after ART initiation. Pre-ART attrition decreased from 61% pre-clinic to 50% post-clinic (p<0.001). Pre-ART attrition was associated with being female (sub-distributional hazard ratio (sHR): 1.59; CI: 1.31-1.93), syphilis diagnosis (sHR: 1.47; CI: 1.16-1.85) and slum residence (sHR: 0.84; CI: 0.72-0.97). ART attrition was associated with syphilis diagnosis (hazard ratio (HR): 2.23; CI: 1.35-3.68) and CD4 <50 cells/µL (HR: 1.88; CI: 1.15-3.06). CONCLUSIONS: Implementation of a youth-friendly adolescent clinic improved retention in HIV care among adolescents, particularly in the assessment of ART eligibility and ART initiation. Additional interventions are needed to improve retention among pre-ART patients and support long-term retention among ART patients.
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Instituições de Assistência Ambulatorial , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/terapia , Adolescente , Contagem de Linfócito CD4 , Estudos de Coortes , Definição da Elegibilidade , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Haiti , Humanos , Masculino , Modelos de Riscos Proporcionais , Sífilis , Adulto JovemRESUMO
Landscape fragmentation is often a major cause of species extinction as it can affect a wide variety of ecological processes. The impact of fragmentation varies among species depending on many factors, including their life-history traits and dispersal abilities. Felids are one of the groups most threatened by fragmented landscapes because of their large home ranges, territorial behavior, and low population densities. Here, we model the impacts of habitat fragmentation on patterns of genetic diversity in the guigna (Leopardus guigna), a small felid that is closely associated with the heavily human-impacted temperate rainforests of southern South America. We assessed genetic variation in 1798 base pairs of mitochondrial DNA sequences, 15 microsatellite loci, and 2 sex chromosome genes and estimated genetic diversity, kinship, inbreeding, and dispersal in 38 individuals from landscapes with differing degrees of fragmentation on Chiloé Island in southern Chile. Increased fragmentation was associated with reduced genetic diversity, but not with increased kinship or inbreeding. However, in fragmented landscapes, there was a weaker negative correlation between pairwise kinship and geographic distance, suggesting increased dispersal distances. These results highlight the importance of biological corridors to maximize connectivity in fragmented landscapes and contribute to our understanding of the broader genetic consequences of habitat fragmentation, especially for forest-specialist carnivores.
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Ecossistema , Felidae/genética , Variação Genética , Genética Populacional , Animais , Chile , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , Repetições de Microssatélites , Filogeografia , Densidade Demográfica , Floresta Úmida , Análise de Sequência de DNARESUMO
BACKGROUND: The role of the host immunity in determining leprosy clinical forms and complications is well recognized, implying that changes in the immune status may interfere with several aspects of the disease. Therefore, we hypothesized that the presence of viral co-infections and associated immunological changes will have a clinical impact on leprosy outcomes. The aim of our study was to determine the clinical impact of human immunodeficiency virus (HIV), human T cell lymphotrophic virus type 1 (HTLV-1), hepatitis B virus (HBV) and hepatitis C virus (HCV) co-infection on the development of reactions, neuritis, neuropathy and relapses. METHODOLOGY/PRINCIPAL FINDINGS: Cohort study in 245 leprosy subjects from Bahia, Brazil. Patients were followed from the time of diagnosis until at least the end of multidrug therapy. Viral co-infection was detected in 36 out of the 245 patients (14.7%). Specific co-infection rates were 10.6% for HBV, 2.9% for HIV, 2.5% for HTLV-1 and 0.8% for HCV. All four groups of co-infected patients had higher rates of neuritis and nerve function impairment compared to non co-infected leprosy subjects. The relapse rate was also higher in the co-infected group (8.3%) versus patients without co-infection (1.9%); relative risk 4.37, 95% confidence interval 1.02-18.74. CONCLUSIONS/SIGNIFICANCE: Leprosy patients should be screened for HBV, HCV, HIV and HTLV-1 co-infections. Besides contributing to better health care, this measure will facilitate the early detection of severe complications through targeting of higher risk patients.
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Coinfecção/microbiologia , Coinfecção/virologia , Hanseníase/microbiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Coinfecção/complicações , Feminino , Infecções por HIV/virologia , HIV-1/fisiologia , Infecções por HTLV-I/virologia , Hepacivirus/fisiologia , Hepatite B/virologia , Vírus da Hepatite B/fisiologia , Hepatite C/virologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Humanos , Hanseníase/complicações , Hanseníase/virologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/fisiologia , Adulto JovemRESUMO
In spite of potentially being an important source of rhizobial diversity and a key determinant of common bean productivity, there is a paucity of data on Rhizobium genetic variation and species composition in the important bean producing area of Chile and only one species has been documented (Rhizobium leguminosarum). In this study, 240 Rhizobium isolates from Torcaza bean (Phaseolus vulgaris L.) nodules established in the highest bean producing area in Chile (33°34'S-70°38'W and 37°36'S-71°47'W) were characterized by PCR-RFLP markers for nodC gene, revealing eight banding patterns with the polymorphic enzyme Hinf I. The locality of San Agustín de Aurora in Central Chile (35°32'S-71°29'W) had the highest level of diversity. Isolates were classified by species using PCR-RFLP markers for 16S rDNA gene and were confirmed by sequencing an internal fragment of the 16S rDNA gene. The results confirmed the presence of R. leguminosarum and three other species of rhizobia nodulating beans in South Central Chile (R. etli, R. tropici and R. leucaenae). R. tropici and R. leucaenae showed the least genetic variation and were most commonly identified in acid soils, while R. etli was the most common species in slightly acidic to moderately alkaline soils, with higher levels of organic matter content. R. leguminosarum was identified in almost all soils, was the most genetically diverse, and was the most common, being documented in soils with pH that ranged between 5.3 and 8.2, and with organic matter content between 2.1 and 4 %.
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Variação Genética , Phaseolus/microbiologia , Rhizobium/genética , Nódulos Radiculares de Plantas/microbiologia , Microbiologia do Solo , Proteínas de Bactérias/genética , Chile , Clima , Concentração de Íons de Hidrogênio , N-Acetilglucosaminiltransferases/genética , Filogenia , RNA Ribossômico 16S/genética , Solo/química , SimbioseRESUMO
Haitian women are twice as likely as men to have HIV/AIDs. Factors underlying the feminization of HIV are complex. Self-esteem is an important correlate of sexual behavior. However, its meaning and impact on health behaviors may be influenced by cultural factors. This qualitative study took place in Haiti 4 months after the 2010 earthquake and examines the meaning of self-esteem among young Haitian women seeking treatment for a recurrent sexually transmitted infection (STI). The meaning of self-esteem was derived from a sense of gratitude and was rooted in their ability to provide for family. This may have led to behaviors such as not using condoms or having sex with partners in concurrent relationships. This article highlights the resilience and resourcefulness of Haitian women, provides insight into how women with apparent positive self-images were led to make choices that placed them at high risk for contracting HIV, and concludes with recommendations for future interventions.
Assuntos
Aceitação pelo Paciente de Cuidados de Saúde , Resiliência Psicológica , Autoimagem , Comportamento Sexual , Infecções Sexualmente Transmissíveis/psicologia , Adolescente , Adulto , Preservativos/estatística & dados numéricos , Desastres , Terremotos , Feminino , Infecções por HIV/prevenção & controle , Haiti , Humanos , Entrevistas como Assunto , Acontecimentos que Mudam a Vida , Pesquisa Qualitativa , Fatores de Risco , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/terapia , Fatores Socioeconômicos , Adulto JovemRESUMO
Fifteen guanacos were introduced to Staats Island in the Falklands/Malvinas archipelago from Patagonia in the 1930s. Twenty five years later, the population was culled from 300 to 10-20 individuals, but quickly rebounded to a population of almost 400 animals that today retain the genetic signature of the founding event and later bottleneck. The goals of this study were to (i) make a genetic assessment of this island population through comparisons with mainland populations and simulations, and (ii) assess the likely source-population of the introduced guanacos. Genetic variation was estimated from 513 bp of mitochondrial DNA sequence and 15 microsatellite loci among 154 guanacos collected from eight localities, including the adjacent mainland and the islands of Tierra del Fuego and Staats Island. Of the 23 haplotypes observed among our samples, the Staats Island population only contained three haplotypes, all of which were shared with the coastal Monte Leon population in southern Patagonia. Mitochondrial DNA and microsatellite variations on Staats Island were comparable to most mainland populations and greater than those observed on Tierra del Fuego. Patterns of genetic structure suggest that the Staats Island guanaco population was founded with animals from southern Patagonia (as opposed to northern Patagonia or Tierra del Fuego), but that effective reductions in population size lasted only a few generations and that surviving animals were a random sample of the pre-bottleneck genetic variation.
Assuntos
Camelídeos Americanos/genética , Conservação dos Recursos Naturais , Efeito Fundador , Variação Genética , Ilhas , Animais , DNA Mitocondrial/genética , Feminino , Endogamia , Masculino , Repetições de Microssatélites/genética , Modelos GenéticosRESUMO
For 3 decades, GHESKIO (the Groupe Haitien d'Etude du Sarcome de Kaposi et des Infections Opportunistes), the Haitian Ministry of Health, and Weill Cornell have pursued a tripartite mission of service, training, and translational research. The initial focus was on AIDS and tuberculosis. The mission has expanded to include the local community and now provides maternal-child health, family planning, cancer prevention and treatment, immunizations (including human papillomavirus, cholera), and primary education through vocational and microcredit programs. Outcome measures include a reduction in HIV prevalence from 6.2% to the current 2.2%, extensive tuberculosis and cholera prevention and treatment programs, and national training programs for biomedical and community health workers.