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1.
Article in English | MEDLINE | ID: mdl-35528706

ABSTRACT

Background: An obesity epidemic has been documented among adult Latinos/as in Latin America and the United States (US); however, little is known about obesity among Latinos/as with HIV (PWH). Moreover, Latinos/as PWH in the US may have different weight trajectories than those in Latin America due to the cultural and environmental contexts. We assessed weight and body mass index (BMI) trajectories among PWH initiating antiretroviral therapy (ART) across 5 countries in Latin America and the Caribbean and the US. Methods: ART-naÿve PWH ≥18 years old, enrolled in Brazil, Honduras, Mexico, Peru, and Haiti (sites within CCA-SAnet) and the US (NA-ACCORD) starting ART between 2000 and 2017, with at least one weight measured after ART initiation were included. Participants were classified according to site/ethnicity as: Latinos/as in US, non-Latinos/as in US, Haitians, and Latinos/as in Latin America. Generalized least squares models were used to assess trends in weight and BMI. Models estimating probabilities of becoming overweight/obese (BMI ≥25 kg/m2) and of becoming obese (BMI ≥30 kg/m2) post ART initiation for males and females were fit using generalized estimating equations with a logit link and an independence working correlation structure. Findings: Among 59,207 PWH, 9% were Latinos/as from Latin America, 9% Latinos/as from the US, 68% non-Latinos/as from the US and 14% were Haitian. At ART initiation, 29% were overweight and 14% were obese. Post-ART weight and BMI increases were steeper for Latinos/as in Latin America compared with other sites/ethnicities; however, BMI at 3-years post ART remained lower compared to Latinos/as and non-Latinos/as in the US. Among females, at 3-years post ART initiation the greatest adjusted probability of obesity was found among non-Latinas in the US (15·2%) and lowest among Latinas in Latin America (8.6%). Among males, while starting with a lower BMI, Latinos in Latin America had the greatest adjusted probability of becoming overweight or obese 3-years post-ART initiation. Interpretation: In the Americas, PWH gain substantial weight after ART initiation. Despite environmental and cultural differences, PWH in Latin America, Haiti and Latinos and non-Latinos in the US share similar BMI trajectories on ART and high probabilities of becoming overweight and obese over time. Multicohort studies are needed to better understand the burden of other metabolic syndrome components in PWH across different countries.

2.
J Acquir Immune Defic Syndr ; 82(1): 71-80, 2019 09 01.
Article in English | MEDLINE | ID: mdl-31107304

ABSTRACT

BACKGROUND: Hepatitis B virus (HBV) infection is a leading cause of end-stage liver disease (ESLD) and hepatocellular carcinoma (HCC) in HIV. Factors contributing to the high rates of liver complications among HIV/HBV-coinfected individuals remain unknown. SETTING: North American AIDS Cohort Collaboration on Research and Design. METHODS: We performed a retrospective cohort study among HIV/HBV-coinfected patients in 10 US and Canadian cohorts of the North American AIDS Cohort Collaboration on Research and Design that validated ESLD (ascites, spontaneous bacterial peritonitis, variceal hemorrhage, and/or hepatic encephalopathy) and HCC diagnoses from 1996 to 2010. Multivariable Cox regression was used to examine adjusted hazard ratios [aHRs with 95% confidence interval (CIs)] of liver complications (first occurrence of ESLD or HCC) associated with hypothesized determinants and with increasing durations of HIV suppression (≤500 copies/mL). RESULTS: Among 3573 HIV/HBV patients with 13,790 person-years of follow-up, 111 liver complications occurred (incidence rate = 8.0 [95% CI: 6.6 to 9.7] events/1000 person-years). Rates of liver complication were increased with non-black/non-Hispanic race [aHR = 1.76 (1.13-2.74)], diabetes mellitus [aHR = 2.07 (1.20-3.57)], lower time-updated CD4 cell count [<200 cells/mm: aHR = 2.59 (1.36-4.91); 201-499 cells/mm: aHR = 1.75 (1.01-3.06) versus ≥500 cells/mm], heavy alcohol use [aHR = 1.58 (1.04-2.39)], and higher FIB-4 at start of follow-up [>3.25: aHR = 9.79 (5.73-16.74); 1.45-3.25: aHR = 3.20 (1.87-5.47) versus FIB-4 <1.45]. HIV suppression for ≥6 months was associated with lower liver complication rates compared with those with unsuppressed HIV [aHR = 0.56 (0.35-0.91)]. CONCLUSIONS: Non-black/non-Hispanic race, diabetes, lower CD4 cell count, heavy alcohol use, and advanced liver fibrosis were determinants of liver complications among HIV/HBV patients. Sustained HIV suppression should be a focus for HIV/HBV-coinfected patients to reduce the risks of ESLD/HCC.


Subject(s)
HIV Infections/complications , HIV Infections/epidemiology , Hepatitis B/complications , Hepatitis B/epidemiology , Adult , CD4 Lymphocyte Count , Canada , Carcinoma, Hepatocellular/complications , Carcinoma, Hepatocellular/epidemiology , End Stage Liver Disease/complications , Esophageal and Gastric Varices , Female , Gastrointestinal Hemorrhage , Humans , Liver , Liver Cirrhosis/complications , Liver Cirrhosis/epidemiology , Liver Neoplasms/complications , Liver Neoplasms/epidemiology , Male , Middle Aged , Retrospective Studies , Risk Factors , United States
3.
J Acquir Immune Defic Syndr ; 79(4): 421-429, 2018 12 01.
Article in English | MEDLINE | ID: mdl-30211722

ABSTRACT

BACKGROUND: It is not known whether immune dysfunction is associated with increased risk of death after cancer diagnosis in persons with HIV (PWH). AIDS-defining illness (ADI) can signal significant immunosuppression. Our objective was to determine differences in cancer stage and mortality rates in PWH with and without history of ADI. METHODS: PWH with anal, oropharynx, cervical, lung cancers, or Hodgkin lymphoma diagnoses from January 2000 to December 2009 in the North American AIDS Cohort Collaboration on Research and Design were included. RESULTS: Among 81,865 PWH, 814 had diagnoses included in the study; 341 (39%) had a history of ADI at time of cancer diagnosis. For each cancer type, stage at diagnosis did not differ by ADI (P > 0.05). Mortality and survival estimates for cervical cancer were limited by n = 5 diagnoses. Adjusted mortality rate ratios showed a 30%-70% increase in mortality among those with ADI for all cancer diagnoses, although only lung cancer was statistically significant. Survival after lung cancer diagnosis was poorer in PWH with ADI vs. without (P = 0.0001); the probability of survival was also poorer in those with ADI at, or before other cancers although not statistically significant. CONCLUSIONS: PWH with a history of ADI at lung cancer diagnosis had higher mortality and poorer survival after diagnosis compared to those without. Although not statistically significant, the findings of increased mortality and decreased survival among those with ADI (vs. without) were consistent for all other cancers, suggesting the need for further investigations into the role of HIV-related immune suppression and cancer outcomes.


Subject(s)
HIV Infections/complications , Neoplasms/mortality , Neoplasms/pathology , Adult , Female , Humans , Male , Middle Aged , Neoplasm Staging , Survival Analysis
4.
Lancet HIV ; 5(8): e438-e447, 2018 08.
Article in English | MEDLINE | ID: mdl-30025681

ABSTRACT

BACKGROUND: Evidence on viral load and HIV transmission risk in HIV-serodiscordant male homosexual couples is limited to one published study. We calculated transmission rates in couples reporting condomless anal intercourse (CLAI), when HIV-positive partners were virally suppressed, and daily pre-exposure prophylaxis (PrEP) was not used by HIV-negative partners. METHODS: In the Opposites Attract observational cohort study, serodiscordant male homosexual couples were recruited from 13 clinics in Australia, one in Brazil, and one in Thailand. At study visits, HIV-negative partners provided information on sexual behaviour and were tested for HIV and sexually transmitted infections; HIV-positive partners had HIV viral load tests, CD4 cell count, and sexually transmitted infection tests done. Viral suppression was defined as less than 200 copies per mL. Linked within-couple HIV transmissions were identified with phylogenetic analysis. Incidence was calculated per couple-year of follow-up, focusing on periods with CLAI, no use of daily PrEP, and viral suppression. One-sided upper 95% CI limits for HIV transmission rates were calculated with exact Poisson methods. FINDINGS: From May 8, 2012, to March 31, 2016, in Australia, and May 7, 2014, to March 31, 2016, in Brazil and Thailand, 358 couples were enrolled. 343 couples had at least one follow-up visit and were followed up for 588·4 couple-years. 258 (75%) of 343 HIV-positive partners had viral loads consistently less than 200 copies per mL and 115 (34%) of 343 HIV-negative partners used daily PrEP during follow-up. 253 (74%) of 343 couples reported within-couple CLAI during follow-up, with a total of 16 800 CLAI acts. Three new HIV infections occurred but none were phylogenetically linked. There were 232·2 couple-years of follow-up and 12 447 CLAI acts in periods when CLAI was reported, HIV-positive partners were virally suppressed, and HIV-negative partners did not use daily PrEP, resulting in an upper CI limit of 1·59 per 100 couple-years of follow-up for transmission rate. INTERPRETATION: HIV treatment as prevention is effective in men who have sex with men. Increasing HIV testing and linking to immediate treatment is an important strategy in HIV prevention in homosexual men. FUNDING: National Health and Medical Research Council; amfAR, The Foundation for AIDS Research; ViiV Healthcare; and Gilead Sciences.


Subject(s)
HIV Infections/prevention & control , HIV Infections/transmission , Viral Load , Adult , Anti-HIV Agents/therapeutic use , Australia , Brazil , CD4 Lymphocyte Count , Condoms , HIV/genetics , HIV Infections/drug therapy , Homosexuality, Male , Humans , Male , Middle Aged , Phylogeny , Pre-Exposure Prophylaxis , Prospective Studies , Sexual Behavior , Sexual and Gender Minorities , Thailand
5.
Am J Bot ; 104(1): 116-126, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28082282

ABSTRACT

PREMISE OF THE STUDY: The red flesh of some papaya cultivars is caused by a recessive loss-of-function mutation in the coding region of the chromoplast-specific lycopene beta cyclase gene (CYC-b). We performed an evolutionary genetic analysis of the CYC-b locus in wild and cultivated papaya to uncover the origin of this loss-of-function allele in cultivated papaya. METHODS: We analyzed the levels and patterns of genetic diversity at the CYC-b locus and six loci in a 100-kb region flanking CYC-b and compared these to genetic diversity levels at neutral autosomal loci. The evolutionary relationships of CYC-b haplotypes were assessed using haplotype network analysis of the CYC-b locus and the 100-kb CYC-b region. KEY RESULTS: Genetic diversity at the recessive CYC-b allele (y) was much lower relative to the dominant Y allele found in yellow-fleshed wild and cultivated papaya due to a strong selective sweep. Haplotype network analyses suggest the y allele most likely arose in the wild and was introduced into domesticated varieties after the first papaya domestication event. The shared haplotype structure between some wild, feral, and cultivated haplotypes around the y allele supports subsequent escape of this allele from red cultivars back into wild populations through feral intermediates. CONCLUSIONS: Our study supports a protracted domestication process of papaya through the introgression of wild-derived traits and gene flow from cultivars to wild populations. Evidence of gene flow from cultivars to wild populations through feral intermediates has implications for the introduction of transgenic papaya into Central American countries.


Subject(s)
Carica/genetics , Evolution, Molecular , Genetic Variation , Intramolecular Lyases/genetics , Plant Proteins/genetics , Alleles , Carica/classification , Carica/enzymology , Central America , Gene Flow , Gene Frequency , Genetics, Population , Haplotypes , Intramolecular Lyases/classification , Models, Genetic , Mutation , Phenotype , Phylogeny , Plant Proteins/classification , Plastids/genetics
6.
J Int AIDS Soc ; 19(1): 20684, 2016.
Article in English | MEDLINE | ID: mdl-26996992

ABSTRACT

INTRODUCTION: Latinos living with HIV in the Americas share a common ethnic and cultural heritage. In North America, Latinos have a relatively high rate of new HIV infections but lower rates of engagement at all stages of the care continuum, whereas in Latin America antiretroviral therapy (ART) services continue to expand to meet treatment needs. In this analysis, we compare HIV treatment outcomes between Latinos receiving ART in North America versus Latin America. METHODS: HIV-positive adults initiating ART at Caribbean, Central and South America Network for HIV (CCASAnet) sites were compared to Latino patients (based on country of origin or ethnic identity) starting treatment at North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) sites in the United States and Canada between 2000 and 2011. Cox proportional hazards models compared mortality, treatment interruption, antiretroviral regimen change, virologic failure and loss to follow-up between cohorts. RESULTS: The study included 8400 CCASAnet and 2786 NA-ACCORD patients initiating ART. CCASAnet patients were younger (median 35 vs. 37 years), more likely to be female (27% vs. 20%) and had lower nadir CD4 count (median 148 vs. 195 cells/µL, p<0.001 for all). In multivariable analyses, CCASAnet patients had a higher risk of mortality after ART initiation (adjusted hazard ratio (AHR) 1.61; 95% confidence interval (CI): 1.32 to 1.96), particularly during the first year, but a lower hazard of treatment interruption (AHR: 0.46; 95% CI: 0.42 to 0.50), change to second-line ART (AHR: 0.56; 95% CI: 0.51 to 0.62) and virologic failure (AHR: 0.52; 95% CI: 0.48 to 0.57). CONCLUSIONS: HIV-positive Latinos initiating ART in Latin America have greater continuity of treatment but are at higher risk of death than Latinos in North America. Factors underlying these differences, such as HIV testing, linkage and access to care, warrant further investigation.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Adult , Canada , Female , Hispanic or Latino , Humans , Male , North America , Proportional Hazards Models , South America , Treatment Outcome , United States
7.
J Acquir Immune Defic Syndr ; 70(3): 275-9, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-26068721

ABSTRACT

Screening persons living with HIV for gonorrhea and chlamydia has been recommended since 2003. We compared annual gonorrhea/chlamydia testing to syphilis and lipid testing among 19,368 adults (41% men who have sex with men, 30% heterosexual men, and 29% women) engaged in HIV care. In 2004, 22%, 62%, and 70% of all patients were tested for gonorrhea/chlamydia, syphilis, and lipid levels, respectively. Despite increasing steadily [odds ratio per year (95% confidence interval): 1.14 (1.13 to 1.15)], gonorrhea/chlamydia testing in 2010 remained lower than syphilis and lipid testing (39%, 77%, 76%, respectively). Interventions to improve gonorrhea/chlamydia screening are needed. A more targeted screening approach may be warranted.


Subject(s)
Chlamydia Infections/diagnosis , Gonorrhea/diagnosis , HIV Infections/complications , Adolescent , Adult , Ambulatory Care Facilities , Chlamydia , Chlamydia Infections/complications , Chlamydia Infections/epidemiology , Female , Gonorrhea/complications , Gonorrhea/epidemiology , Humans , Male , Middle Aged , United States/epidemiology , Young Adult
8.
BMC Infect Dis ; 14: 699, 2014 Dec 19.
Article in English | MEDLINE | ID: mdl-25523385

ABSTRACT

BACKGROUND: World-wide, the notable expansion of HIV/AIDS treatment programs in resource-limited settings has lead to an increasing number of patients in need of second-line cART. To adequately address and prepare for this scenario, critical assessments of the outcomes of second-line cART are particularly relevant in settings where monitoring strategies may be inadequate. We evaluated virologic outcomes of second-line combination antiretroviral therapy (cART) among HIV-infected individuals from Brazil. METHODS: This study was conducted at the Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, at Rio de Janeiro, Brazio. For this study we included all patients who started first-line and second-line cART between 2000 and 2013. Second-line cART required a switch in the anchor drug of first-line cART. We evaluated time from second-line start to virologic failure and factors associated with increased risk of failure using multivariable Cox proportional hazards regression models. RESULTS: Among the 1,311 patients who started first-line cART a total of 386 patients (29.5%) initiated second-line cART, out of which 35.0% and 60.6% switched from their first-line to their second-line cART when their HIV RNA was undetectable and after documented virologic failure, respectively. At second line cART initiation, median age was 38 years [interquartile range (IQR): 31-45years]. Median CD4 count was significantly different for patients starting second-line cART undetectable [412 cells/mm3 (IQR: 240-617)] compared to those starting second-line cART after documented virologic failure [230 cells/mm3 (IQR: 118-322.5)] (p < 0.01). Median time from second-line cART initiation to failure was also significantly different for patients starting second-line cART undetectable compared to those who with documented virologic failure (log-rank test p < 0.01). Multivariable Cox models showed that younger age, lower education, and HIV RNA level were independently associated with an increased hazard of second-line failure among those with documented virologic failure at start of second-line cART. CONCLUSIONS: We have shown that in a middle-income country with universal access to cART, having a detectable HIV RNA at the start of second-line cART as well as younger age and lower education negatively impact second-line outcomes. Our findings could guide HIV treatment efforts as to which strategies would help maximize the durability of these regimens.


Subject(s)
HIV Infections/drug therapy , HIV Protease Inhibitors/therapeutic use , RNA, Viral/blood , Reverse Transcriptase Inhibitors/therapeutic use , Adult , Age Factors , Anti-Retroviral Agents/therapeutic use , Brazil , CD4 Lymphocyte Count , Cohort Studies , Databases, Factual , Educational Status , Female , HIV Infections/blood , Humans , Male , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Retrospective Studies , Treatment Failure , Treatment Outcome , Viral Load
9.
J Acquir Immune Defic Syndr ; 67(1): 84-90, 2014 Sep 01.
Article in English | MEDLINE | ID: mdl-24872131

ABSTRACT

BACKGROUND: Earlier HIV diagnosis and engagement in care improve outcomes and is cost effective, as a result, in 2006, the Centers for Disease Control and Prevention (CDC) revised the HIV-screening guidelines. We sought to determine whether the CD4 count (CD4) at presentation, a surrogate for time to presentation, increased during the study period. Our a priori hypothesis was that the CD4 at presentation increased during the study period, particularly after the CDC guideline revision. METHODS: We performed a retrospective cohort study and analyzed data from the HIV Research Network, a consortium of 18 US clinics caring for HIV-infected patients. HIV-infected adults (≥18 years old) newly presenting for care between 2003 and 2011 were included in this study. Multivariable linear regression examined associations with CD4 at enrollment. Calendar year was modeled as a linear spline with a change in slope at 2008, allowing determination of the mean change in CD4 per year during 2003-2007 and 2008-2011. RESULTS: Over 13,543 newly presenting subjects enrolled from 2003 to 2011. Median CD4 at enrollment rose from 285 to 317 cells per cubic millimeter between 2003-2007 and 2008-2011 (P < 0.001). After adjusting for age, race/ethnicity, gender, HIV risk factor, and clinic site, the mean increase in the CD4 count at presentation per year was 13.3 cells per cubic millimeter per year (95% confidence interval 6.4 to 20.1 cells per cubic millimeter per year) greater during 2008-2011 than during 2003-2007. CONCLUSIONS: We demonstrate a small, but statistically significant, increase in CD4 at presentation after the CDC guideline revision. More efforts are needed to decrease time to presentation to HIV care.


Subject(s)
CD4 Lymphocyte Count/statistics & numerical data , HIV Infections/epidemiology , HIV Infections/immunology , HIV-1/isolation & purification , Adult , Anti-Retroviral Agents/administration & dosage , Cohort Studies , Female , HIV Infections/drug therapy , HIV Infections/virology , Humans , Linear Models , Male , Middle Aged , Multivariate Analysis , RNA, Viral/blood , Retrospective Studies , United States/epidemiology
10.
PLoS One ; 9(4): e93039, 2014.
Article in English | MEDLINE | ID: mdl-24695533

ABSTRACT

OBJECTIVE: There is a continuous debate on how to adequately evaluate long-term CD4+ cell count in response to combination antiretroviral therapy (ART) among human immunodeficiency virus (HIV)-infected individuals. Our study evaluated the long-term CD4+ cell count response (up to ten years) after initiation of ART and described the differences in the CD4+ cell count response stratified by pretreatment CD4+ cell count, and other socio-demographic, behavioral, and clinical factors. METHODS: The study population included patients starting ART in the clinical cohorts of Rio de Janeiro, Brazil, and Baltimore, United States. Inverse probability of censoring weighting was used to estimate mean annual CD4+ cell counts while adjusting for choice of initial ART regimen, ART discontinuation and losses-to-follow-up. RESULTS: From 1997 to 2011, 3116 individuals started ART; preferred initial regimen was NNRTI-based (63%). The median follow-up time was 5 years, 10% of the individuals had nine or more years of follow-up. Observed CD4+ cell counts increased throughout the ten years of follow-up. Weighted results, in contrast, increased up to year four and plateaued thereafter with 50% of the population reaching CD4+ cell counts of 449/µL or more. Out of all stratification variables considered, only individuals with pre-treatment CD4+ cell counts ≥350/µL showed increasing CD4+ cell counts over time with 76% surpassing the CD4+ cell count >500/µL threshold at year ten. CONCLUSION: The present study corroborates the growing body of knowledge advocating early start of ART by showing that only patients who start ART early fully recover to normal CD4+ cell counts.


Subject(s)
Anti-Retroviral Agents/administration & dosage , HIV Infections , Adult , Aged , Baltimore/epidemiology , Brazil/epidemiology , CD4 Lymphocyte Count , Female , Follow-Up Studies , HIV Infections/blood , HIV Infections/drug therapy , HIV Infections/epidemiology , HIV Infections/immunology , Humans , Male , Middle Aged , Retrospective Studies , Risk-Taking , Socioeconomic Factors
11.
Am J Obstet Gynecol ; 211(1): 68.e1-8, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24530815

ABSTRACT

OBJECTIVE: Recurrence following primary platinum-based chemotherapy remains a challenge in the treatment of patients with advanced-stage epithelial ovarian cancer. This study examines whether a chemoresponse assay can identify patients who are platinum-resistant prior to treatment. STUDY DESIGN: Women (n = 276) with International Federation of Gynecology and Obstetrics stage III-IV ovarian, fallopian, and peritoneal cancer were enrolled in an observational study, and the responsiveness of their tumors was evaluated using a chemoresponse assay. All patients were treated with a platinum/taxane regimen following cytoreductive surgery. Assay responses to carboplatin or paclitaxel were classified as sensitive, intermediate sensitive (IS), or resistant. Association of assay response with progression-free survival (PFS) was analyzed using the Kaplan-Meier method and a Cox regression model. RESULTS: Patients whose tumors were resistant to carboplatin were at increased risk of disease progression compared to those with nonresistant (sensitive + IS) tumors (median PFS: 11.8 vs 16.6 months, respectively, P < .001), and the association was confirmed after adjusting for other clinical factors (hazard ratio, 1.71; 95% confidence interval, 1.12-2.62; P = .013). Association of assay response to paclitaxel with PFS trended in multivariate analysis (hazard ratio, 1.28; 95% confidence interval, 0.84-1.95; P = .245). For tumors resistant to carboplatin, 59% were sensitive or IS to at least 1 other commonly used agent, demonstrating the ability of the assay to inform treatment decisions beyond the standard platinum/taxane regimen. CONCLUSION: Assay resistance to carboplatin is strongly associated with shortened PFS among advanced-stage epithelial ovarian cancer patients treated with carboplatin + paclitaxel therapy, supporting use of this assay to identify patients likely to experience early recurrence on standard platinum-based therapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Drug Resistance, Neoplasm , Neoplasm Recurrence, Local/prevention & control , Neoplasms, Glandular and Epithelial/drug therapy , Ovarian Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/administration & dosage , Carboplatin/administration & dosage , Carcinoma, Ovarian Epithelial , Chemotherapy, Adjuvant , Female , Follow-Up Studies , Humans , Middle Aged , Multivariate Analysis , Neoplasm Recurrence, Local/etiology , Neoplasm Staging , Neoplasms, Glandular and Epithelial/pathology , Neoplasms, Glandular and Epithelial/surgery , Ovarian Neoplasms/pathology , Ovarian Neoplasms/surgery , Paclitaxel/administration & dosage , Prospective Studies , ROC Curve , Survival Analysis , Treatment Outcome
12.
J Venom Anim Toxins Incl Trop Dis ; 19(1): 21, 2013 Sep 27.
Article in English | MEDLINE | ID: mdl-24074353

ABSTRACT

Only seven types of mammals are known to be venomous, including slow lorises (Nycticebus spp.). Despite the evolutionary significance of this unique adaptation amongst Nycticebus, the structure and function of slow loris venom is only just beginning to be understood. Here we review what is known about the chemical structure of slow loris venom. Research on a handful of captive samples from three of eight slow loris species reveals that the protein within slow loris venom resembles the disulphide-bridged heterodimeric structure of Fel-d1, more commonly known as cat allergen. In a comparison of N. pygmaeus and N. coucang, 212 and 68 compounds were found, respectively. Venom is activated by combining the oil from the brachial arm gland with saliva, and can cause death in small mammals and anaphylactic shock and death in humans. We examine four hypotheses for the function of slow loris venom. The least evidence is found for the hypothesis that loris venom evolved to kill prey. Although the venom's primary function in nature seems to be as a defense against parasites and conspecifics, it may also serve to thwart olfactory-orientated predators. Combined with numerous other serpentine features of slow lorises, including extra vertebra in the spine leading to snake-like movement, serpentine aggressive vocalisations, a long dark dorsal stripe and the venom itself, we propose that venom may have evolved to mimic cobras (Naja sp.). During the Miocene when both slow lorises and cobras migrated throughout Southeast Asia, the evolution of venom may have been an adaptive strategy against predators used by slow lorises as a form of Müllerian mimicry with spectacled cobras.

13.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;19maio 2013.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1484538

ABSTRACT

Only seven types of mammals are known to be venomous, including slow lorises (Nycticebus spp.). Despite the evolutionary significance of this unique adaptation amongst Nycticebus, the structure and function of slow loris venom is only just beginning to be understood. Here we review what is known about the chemical structure of slow loris venom. Research on a handful of captive samples from three of eight slow loris species reveals that the protein within slow loris venom resembles the disulphide-bridged heterodimeric structure of Fel-d1, more commonly known as cat allergen. In a comparison of N. pygmaeus and N. coucang, 212 and 68 compounds were found, respectively. Venom is activated by combining the oil from the brachial arm gland with saliva, and can cause death in small mammals and anaphylactic shock and death in humans. We examine four hypotheses for the function of slow loris venom. The least evidence is found for the hypothesis that loris venom evolved to kill prey. Although the venom's primary function in nature seems to be as a defense against parasites and conspecifics, it may also serve to thwart olfactory-orientated predators. Combined with numerous other serpentine features of slow lorises, including extra vertebra in the spine leading to snake-like movement, serpentine aggressive vocalisations, a long dark dorsal stripe and the venom itself, we propose that venom may have evolved to mimic cobras (Naja sp.). During the Miocene when both slow lorises and cobras migrated throughout Southeast Asia, the evolution of venom may have been an adaptive strategy against predators used by slow lorises as a form of Müllerian mimicry with spectacled cobras.

14.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;19: 21, maio 2013. graf, ilus, graf
Article in English | LILACS, VETINDEX | ID: biblio-954697

ABSTRACT

Only seven types of mammals are known to be venomous, including slow lorises (Nycticebus spp.). Despite the evolutionary significance of this unique adaptation amongst Nycticebus, the structure and function of slow loris venom is only just beginning to be understood. Here we review what is known about the chemical structure of slow loris venom. Research on a handful of captive samples from three of eight slow loris species reveals that the protein within slow loris venom resembles the disulphide-bridged heterodimeric structure of Fel-d1, more commonly known as cat allergen. In a comparison of N. pygmaeus and N. coucang, 212 and 68 compounds were found, respectively. Venom is activated by combining the oil from the brachial arm gland with saliva, and can cause death in small mammals and anaphylactic shock and death in humans. We examine four hypotheses for the function of slow loris venom. The least evidence is found for the hypothesis that loris venom evolved to kill prey. Although the venom's primary function in nature seems to be as a defense against parasites and conspecifics, it may also serve to thwart olfactory-orientated predators. Combined with numerous other serpentine features of slow lorises, including extra vertebra in the spine leading to snake-like movement, serpentine aggressive vocalisations, a long dark dorsal stripe and the venom itself, we propose that venom may have evolved to mimic cobras (Naja sp.). During the Miocene when both slow lorises and cobras migrated throughout Southeast Asia, the evolution of venom may have been an adaptive strategy against predators used by slow lorises as a form of Müllerian mimicry with spectacled cobras.(AU)


Subject(s)
Animals , Venoms/toxicity , Naja naja , Mammals , Ectoparasitic Infestations
15.
Article in English | VETINDEX | ID: vti-443354

ABSTRACT

Only seven types of mammals are known to be venomous, including slow lorises (Nycticebus spp.). Despite the evolutionary significance of this unique adaptation amongst Nycticebus, the structure and function of slow loris venom is only just beginning to be understood. Here we review what is known about the chemical structure of slow loris venom. Research on a handful of captive samples from three of eight slow loris species reveals that the protein within slow loris venom resembles the disulphide-bridged heterodimeric structure of Fel-d1, more commonly known as cat allergen. In a comparison of N. pygmaeus and N. coucang, 212 and 68 compounds were found, respectively. Venom is activated by combining the oil from the brachial arm gland with saliva, and can cause death in small mammals and anaphylactic shock and death in humans. We examine four hypotheses for the function of slow loris venom. The least evidence is found for the hypothesis that loris venom evolved to kill prey. Although the venom's primary function in nature seems to be as a defense against parasites and conspecifics, it may also serve to thwart olfactory-orientated predators. Combined with numerous other serpentine features of slow lorises, including extra vertebra in the spine leading to snake-like movement, serpentine aggressive vocalisations, a long dark dorsal stripe and the venom itself, we propose that venom may have evolved to mimic cobras (Naja sp.). During the Miocene when both slow lorises and cobras migrated throughout Southeast Asia, the evolution of venom may have been an adaptive strategy against predators used by slow lorises as a form of Müllerian mimicry with spectacled cobras.

16.
Mol Biol Evol ; 29(12): 3909-20, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22855536

ABSTRACT

The sex chromosomes of the tropical crop papaya (Carica papaya) are evolutionarily young and consequently allow for the examination of evolutionary mechanisms that drive early sex chromosome divergence. We conducted a molecular population genetic analysis of four X/Y gene pairs from a collection of 45 wild papaya accessions. These population genetic analyses reveal striking differences in the patterns of polymorphism between the X and Y chromosomes that distinguish them from other sex chromosome systems. In most sex chromosome systems, the Y chromosome displays significantly reduced polymorphism levels, whereas the X chromosome maintains a level of polymorphism that is comparable to autosomal loci. However, the four papaya sex-linked loci that we examined display diversity patterns that are opposite this trend: the papaya X alleles exhibit significantly reduced polymorphism levels, whereas the papaya Y alleles maintain greater than expected levels of diversity. Our analyses suggest that selective sweeps in the regions of the X have contributed to this pattern while also revealing geographically restricted haplogroups on the Y. We discuss the possible role sexual selection and/or genomic conflict have played in shaping the contrasting patterns of polymorphism found for the papaya X and Y chromosomes.


Subject(s)
Carica/genetics , Chromosomes, Plant/genetics , Evolution, Molecular , Polymorphism, Genetic , Sex Chromosomes/genetics , Costa Rica , Genetics, Population , Haplotypes/genetics , Linkage Disequilibrium , Selection, Genetic , Sex Factors
17.
J Acquir Immune Defic Syndr ; 57 Suppl 3: S171-8, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21857314

ABSTRACT

BACKGROUND: Late presentation to HIV clinical care increases individual risk for (multiple) clinical events and death, and decreases successful response to highly active antiretroviral therapy (HAART). In Brazil, provision of HAART free of charge to all individuals infected with HIV could lead to increased testing and linkage to care. METHODS: We assessed the immune status of 2555 patients who newly presented for HIV clinical care between 1997 and 2009 at the Johns Hopkins Clinical Cohort, in Baltimore, Md, and at the Instituto de Pesquisa Clinica Evandro Chagas Clinical Cohort, in Rio de Janeiro, Brazil. The mean change in the CD4 cell count per year was estimated using multivariate linear regression models. RESULTS: Overall, from 1997 to 2009, 56% and 54% of the patients presented for HIV clinical care with CD4 count ≤350 cells per cubic millimeter in Baltimore and Rio de Janeiro, respectively. On average, 75% of the patients presented with viral load >10,000 copies per millimeter. In Rio de Janeiro only, the overall adjusted per year increase in the mean CD4 cell count was statistically significant (5 cells/mm, 95% confidence interval: 1 to 10 cells/mm). CONCLUSIONS: We found that, over years, the majority of patients presented late, that is, with a CD4 count <350 cells per cubic millimeter. Our findings indicate that, despite the availability of HAART for more than a decade, and mass media campaigns stimulating HIV testing in both countries, the proportion of patients who start therapy at an advanced stage of the disease is still high.


Subject(s)
HIV Infections/diagnosis , HIV Infections/immunology , Adult , Baltimore , Brazil , CD4 Lymphocyte Count , Cohort Studies , Female , HIV Infections/pathology , Humans , Male , Middle Aged , Viral Load
18.
AIDS Res Hum Retroviruses ; 26(8): 865-74, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20672997

ABSTRACT

Studies on the long-term safety and tolerability of HAART are scarce in developing countries. HAART has been universally available in Brazil since 1997, providing a unique opportunity to evaluate the incidence and risk factors for HAART discontinuation or modification. We analyzed retrospective data from 670 treatment-naive patients followed at the HIV cohort of Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation, in Rio de Janeiro, Brazil, who first received HAART between January 1996 and December 2006. Our four outcomes of interest were treatment failure (TF-MOD), short-term toxicity (ST-MOD), long-term toxicity (LT-MOD), and overall modification/discontinuation (MOD, composed of TF-MOD, ST-MOD, LT-MOD, and other reasons). Risk factors were assessed using Cox's proportional hazards regression. Incidences of MOD, ST-MOD, LT-MOD, and TF-MOD were 28.3, 24.0, 4.0, and 5.6 per 100 persons-years, respectively. MOD was observed in 69% of the patients; 40% of the MODs were toxicity related. The risk of MOD in the first year of treatment was 32% (95% CI: 28.3-35.5%); the median time from HAART initiation to MOD was 14 months (IQR: 3.0-29.5). The most frequent reasons for ST-MOD were gastrointestinal; women had a higher hazard for ST-MOD. Metabolic toxicity was the most frequent reason for LT- MOD, particularly dislipidemia and lipodystrophy. Increased hazard of TF-MOD was observed among those with lower CD4(+) lymphocyte counts (<200 cells/mm(3)). Our results indicate that toxicities can compromise adherence and thus impact future treatment options. This is especially relevant in the context of limited access to second and third line treatment regimens.


Subject(s)
Anti-Retroviral Agents/adverse effects , Antiretroviral Therapy, Highly Active/adverse effects , HIV Infections/epidemiology , Acquired Immunodeficiency Syndrome/epidemiology , Adult , Anti-Retroviral Agents/therapeutic use , Antiretroviral Therapy, Highly Active/statistics & numerical data , Brazil/epidemiology , CD4 Lymphocyte Count , Cohort Studies , Female , Humans , Male , Proportional Hazards Models , Treatment Failure
19.
AIDS ; 23(16): 2107-14, 2009 Oct 23.
Article in English | MEDLINE | ID: mdl-19770698

ABSTRACT

OBJECTIVE: To compare the early mortality pattern and causes of death among patients starting HAART in Brazil and the United States. METHODS: We analyzed the combined data from two clinical cohorts followed at the Johns Hopkins AIDS Service in Baltimore, United States, and the Evandro Chagas Clinical Research Institute AIDS Clinic in Rio de Janeiro, Brazil. Participants included those who entered either cohort between 1999 and 2007 and were antiretroviral naive. Follow-up was at 1 year since HAART initiation. Cox proportional hazards regression analysis was used to assess the role of the city on the risk of death. RESULTS: A total of 859 and 915 participants from Baltimore and Rio de Janeiro, respectively, were included. In Rio de Janeiro, 64.7% of deaths occurred within 90 days of HAART initiation; in Baltimore, 48.9% occurred between 180 and 365 days. AIDS-defining illness (61.8%) and non-AIDS-defining illness (55.6%) predominated as causes of death in Rio de Janeiro and Baltimore, respectively. Risk of death was similar in both cities (hazard ratio 1.04; P value = 0.95) after adjusting for CD4 T cell count, age, sex, HIV risk group, prior AIDS-defining illness, and Pneumocystis jirovecii pneumonia and Mycobacterium avium prophylaxis. Individuals with CD4 T cell count less than or equal to 50 cells/microl (hazard ratio 4.36; P = 0.001) or older (hazard ratio, 1.03; P = 0.03) were more likely to die. CONCLUSION: Although late HIV diagnosis is a problem both in developed and developing countries, differences in the timing and causes of deaths clearly indicate that, besides interventions for early HIV diagnosis, different strategies to curb early mortality need to be tailored in each country.


Subject(s)
Antiretroviral Therapy, Highly Active/mortality , HIV Infections/mortality , Adult , Brazil/epidemiology , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , Cause of Death , Cohort Studies , Female , HIV Infections/drug therapy , HIV Infections/immunology , Humans , Male , Middle Aged , Survival Rate , United States/epidemiology , Viral Load
20.
AIDS ; 22(18): 2527-33, 2008 Nov 30.
Article in English | MEDLINE | ID: mdl-19005276

ABSTRACT

BACKGROUND/OBJECTIVE: The risk of recurrent tuberculosis may increase in HIV-infected patients due to exogenous reinfection. We measured the frequency of and determined risk factors for recurrent tuberculosis in a cohort of HIV-infected patients in Rio de Janeiro, Brazil. METHODS: Data were abstracted from medical records of HIV-infected patients attending 29 HIV clinics between 1998 and 2007. Patients analyzed were those who had no tuberculosis history prior to their first HIV clinic visit and who had at least one episode of tuberculosis after entry. Incidence rate ratios compared incidence rates between risk groups and Cox proportional hazards regression models evaluated unadjusted and adjusted associations. RESULTS: Among 1080 HIV-infected patients with tuberculosis, 96 (8.9%) developed a recurrent diagnosis. The median time between diagnoses was 2.4 years. Fewer patients with recurrent tuberculosis had completed their initial 6-month course of tuberculosis treatment compared with patients without recurrence (78 versus 86%; P = 0.02). For patients who completed therapy, the incidence rate of recurrence was 2.5/100 versus 9.0/100 person-years for noncompleters (incidence rate ratio, 3.60; 95% confidence interval, 1.92-6.32). In multivariate modeling, initial tuberculosis treatment completion, receipt of antiretroviral therapy, and CD4 cell count more than 200 mm any time after the initial diagnosis were associated with a significantly decreased hazard of recurrence. CONCLUSION: Tuberculosis recurrence rates were high in this HIV-infected population. Completion of initial tuberculosis therapy, use of antiretroviral therapy, and increases in CD4 cell counts were associated with lower recurrence rates. Use of secondary preventive therapy might be warranted to reduce the burden of tuberculosis in patients with HIV infection.


Subject(s)
AIDS-Related Opportunistic Infections/complications , HIV-1 , Tuberculosis/complications , AIDS-Related Opportunistic Infections/epidemiology , AIDS-Related Opportunistic Infections/prevention & control , Adult , Anti-Retroviral Agents/therapeutic use , Brazil/epidemiology , CD4 Lymphocyte Count , Cohort Studies , Female , Humans , Male , Middle Aged , RNA, Viral , Risk Factors , Secondary Prevention , Tuberculin Test/standards , Tuberculosis/epidemiology , Tuberculosis/prevention & control , Viral Load
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