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1.
Glob Chang Biol ; 27(24): 6498-6511, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34529873

RESUMO

Worldwide, rising ocean temperatures are causing declines and range shifts in marine species. The direct effects of climate change on the biology of marine organisms are often well documented; yet, knowledge on the indirect effects, particularly through trophic interactions, is largely lacking. We provide evidence of ocean warming decoupling critical trophic interactions supporting a commercially important mollusc in a climate change hotspot. Dietary assessments of the Australian blacklip abalone (Haliotis rubra) indicate primary dependency on a widespread macroalgal species (Phyllospora comosa) which we show to be in state of decline due to ocean warming, resulting in abalone biomass reductions. Niche models suggest further declines in P. comosa over the coming decades and ongoing risks to H. rubra. This study highlights the importance of studies from climate change hotspots and understanding the interplay between climate and trophic interactions when determining the likely response of marine species to environmental changes.


Assuntos
Mudança Climática , Pesqueiros , Organismos Aquáticos , Austrália , Biomassa , Ecossistema , Oceanos e Mares
2.
Biol Lett ; 14(9)2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30258032

RESUMO

Researchers are increasingly studying carbon (C) storage by natural ecosystems for climate mitigation, including coastal 'blue carbon' ecosystems. Unfortunately, little guidance on how to achieve robust, cost-effective estimates of blue C stocks to inform inventories exists. We use existing data (492 cores) to develop recommendations on the sampling effort required to achieve robust estimates of blue C. Using a broad-scale, spatially explicit dataset from Victoria, Australia, we applied multiple spatial methods to provide guidelines for reducing variability in estimates of soil C stocks over large areas. With a separate dataset collected across Australia, we evaluated how many samples are needed to capture variability within soil cores and the best methods for extrapolating C to 1 m soil depth. We found that 40 core samples are optimal for capturing C variance across 1000's of kilometres but higher density sampling is required across finer scales (100-200 km). Accounting for environmental variation can further decrease required sampling. The within core analyses showed that nine samples within a core capture the majority of the variability and log-linear equations can accurately extrapolate C. These recommendations can help develop standardized methods for sampling programmes to quantify soil C stocks at national scales.


Assuntos
Carbono/análise , Monitoramento Ambiental/métodos , Solo/química , Austrália , Áreas Alagadas
3.
J Neurovirol ; 22(2): 159-69, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26404435

RESUMO

The prevalence of post-traumatic stress disorder (PTSD) is higher among HIV-infected (HIV+) women compared with HIV-uninfected (HIV-) women, and deficits in episodic memory are a common feature of both PTSD and HIV infection. We investigated the association between a probable PTSD diagnosis using the PTSD Checklist-Civilian (PCL-C) version and verbal learning and memory using the Hopkins Verbal Learning Test in 1004 HIV+ and 496 at-risk HIV- women. HIV infection was not associated with a probable PTSD diagnosis (17% HIV+, 16% HIV-; p = 0.49) but was associated with lower verbal learning (p < 0.01) and memory scores (p < 0.01). Irrespective of HIV status, a probable PTSD diagnosis was associated with poorer performance in verbal learning (p < 0.01) and memory (p < 0.01) and psychomotor speed (p < 0.001). The particular pattern of cognitive correlates of probable PTSD varied depending on exposure to sexual abuse and/or violence, with exposure to either being associated with a greater number of cognitive domains and a worse cognitive profile. A statistical interaction between HIV serostatus and PTSD was observed on the fine motor skills domain (p = 0.03). Among women with probable PTSD, HIV- women performed worse than HIV+ women on fine motor skills (p = 0.01), but among women without probable PTSD, there was no significant difference in performance between the groups (p = 0.59). These findings underscore the importance of considering mental health factors as correlates to cognitive deficits in women with HIV.


Assuntos
Disfunção Cognitiva/fisiopatologia , Infecções por HIV/fisiopatologia , Memória , Desempenho Psicomotor , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Aprendizagem Verbal , Adulto , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/virologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Infecções por HIV/virologia , Humanos , Saúde Mental , Pessoa de Meia-Idade , Testes Neuropsicológicos , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/virologia
4.
J Infect Dis ; 212(9): 1397-401, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25895986

RESUMO

Human immunodeficiency virus (HIV) infectivity increases as receptor/coreceptor expression levels increase. We determined peripheral CD4, CCR5, and CXCR4 expression levels in HIV-uninfected women who used depot medroxyprogesterone acetate (DMPA; n = 32), the levonorgestrel-releasing intrauterine device (LNG-IUD; n = 27), oral contraceptive pills (n = 32), or no hormonal contraception (n = 33). The use of LNG-IUD increased the proportion of CD4(+) and CD8(+) T cells that expressed CCR5; increases in the magnitude of T-cell subset CCR5 expression were observed with DMPA and LNG-IUD use (P < .01 for all comparisons). LNG-IUD and, to a lesser extent, DMPA use were associated with increased peripheral T-cell CCR5 expression.


Assuntos
Anticoncepcionais Orais Combinados/administração & dosagem , Levanogestrel/administração & dosagem , Acetato de Medroxiprogesterona/administração & dosagem , Receptores CCR5/metabolismo , Adulto , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Anticoncepção , Escolaridade , Feminino , Soronegatividade para HIV , Humanos , Receptores CCR5/genética , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Subpopulações de Linfócitos T/metabolismo
5.
Clin Infect Dis ; 61(4): 640-50, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25904369

RESUMO

BACKGROUND: Individuals infected with human immunodeficiency virus (HIV) live longer as a result of effective treatment, but long-term consequences of infection, treatment, and immunological dysfunction are poorly understood. METHODS: We prospectively examined 1011 women (74% HIV-infected) in the Women's Interagency HIV Study and 811 men (65% HIV-infected) in the Multicenter AIDS Cohort Study who underwent repeated B-mode carotid artery ultrasound imaging in 2004-2013. Outcomes included changes in right common carotid artery intima-media thickness (CCA-IMT) and new focal carotid artery plaque formation (IMT >1.5 mm) over median 7 years. We assessed the association between HIV serostatus and progression of subclinical atherosclerosis, adjusting for demographic, behavioral, and cardiometabolic risk factors. RESULTS: Unadjusted mean CCA-IMT increased (725 to 752 µm in women, 757 to 790 µm in men), but CCA-IMT progression did not differ by HIV serostatus, either in combined or sex-specific analyses. Focal plaque prevalence increased from 8% to 15% in women and 25% to 34% in men over 7 years. HIV-infected individuals had 1.6-fold greater risk of new plaque formation compared with HIV-uninfected individuals (relative risk [RR] 1.61, 95% CI, 1.12-2.32), adjusting for cardiometabolic factors; the association was similar by sex. Increased plaque occurred even among persistently virologically suppressed HIV-infected individuals compared with uninfected individuals (RR 1.56, 95% CI, 1.07-2.27). HIV-infected individuals with baseline CD4+ ≥ 500 cells/µL had plaque risk not statistically different from uninfected individuals. CONCLUSIONS: HIV infection is associated with greater increases in focal plaque among women and men, potentially mediated by factors associated with immunodeficiency or HIV replication at levels below current limits of detection.


Assuntos
Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/patologia , Infecções por HIV/complicações , Adulto , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/patologia , Estudos Prospectivos , Túnica Íntima/patologia , Ultrassonografia
6.
Mol Ecol ; 24(19): 4866-85, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26339775

RESUMO

At small spatial and temporal scales, genetic differentiation is largely controlled by constraints on gene flow, while genetic diversity across a species' distribution is shaped on longer temporal and spatial scales. We assess the hypothesis that oceanographic transport and other seascape features explain different scales of genetic structure of giant kelp, Macrocystis pyrifera. We followed a hierarchical approach to perform a microsatellite-based analysis of genetic differentiation in Macrocystis across its distribution in the northeast Pacific. We used seascape genetic approaches to identify large-scale biogeographic population clusters and investigate whether they could be explained by oceanographic transport and other environmental drivers. We then modelled population genetic differentiation within clusters as a function of oceanographic transport and other environmental factors. Five geographic clusters were identified: Alaska/Canada, central California, continental Santa Barbara, California Channel Islands and mainland southern California/Baja California peninsula. The strongest break occurred between central and southern California, with mainland Santa Barbara sites forming a transition zone between the two. Breaks between clusters corresponded approximately to previously identified biogeographic breaks, but were not solely explained by oceanographic transport. An isolation-by-environment (IBE) pattern was observed where the northern and southern Channel Islands clustered together, but not with closer mainland sites, despite the greater distance between them. The strongest environmental association with this IBE pattern was observed with light extinction coefficient, which extends suitable habitat to deeper areas. Within clusters, we found support for previous results showing that oceanographic connectivity plays an important role in the population genetic structure of Macrocystis in the Northern hemisphere.


Assuntos
Genética Populacional , Macrocystis/genética , Alaska , California , Canadá , Ecossistema , Fluxo Gênico , Genótipo , México , Repetições de Microssatélites , Modelos Genéticos , Oceano Pacífico , Filogeografia , Movimentos da Água
7.
J Neurovirol ; 21(4): 422-32, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25791344

RESUMO

In contrast to findings from cohorts comprised primarily of HIV-infected men, verbal memory deficits are the largest cognitive deficit found in HIV-infected women from the Women's Interagency HIV Study (WIHS), and this deficit is not explained by depressive symptoms or substance abuse. HIV-infected women may be at greater risk for verbal memory deficits due to a higher prevalence of cognitive risk factors such as high psychosocial stress and lower socioeconomic status. Here, we investigate the association between perceived stress using the Perceived Stress Scale (PSS-10) and verbal memory performance using the Hopkins Verbal Learning Test (HVLT) in 1009 HIV-infected and 496 at-risk HIV-uninfected WIHS participants. Participants completed a comprehensive neuropsychological test battery which yielded seven cognitive domain scores, including a primary outcome of verbal memory. HIV infection was not associated with a higher prevalence of high perceived stress (i.e., PSS-10 score in the top tertile) but was associated with worse performance on verbal learning (p < 0.01) and memory (p < 0.001), as well as attention (p = 0.02). Regardless of HIV status, high stress was associated with poorer performance in those cognitive domains (p's < 0.05) as well as processing speed (p = 0.01) and executive function (p < 0.01). A significant HIV by stress interaction was found only for the verbal memory domain (p = 0.02); among HIV-infected women only, high stress was associated with lower performance (p's < 0.001). That association was driven by the delayed verbal memory measure in particular. These findings suggest that high levels of perceived stress contribute to the deficits in verbal memory observed in WIHS women.


Assuntos
Transtornos Cognitivos/psicologia , Infecções por HIV/psicologia , Memória , Estresse Psicológico/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Testes Neuropsicológicos
8.
Arterioscler Thromb Vasc Biol ; 34(5): 1085-92, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24651679

RESUMO

OBJECTIVE: Infection with hepatitis C virus (HCV) or human immunodeficiency virus (HIV) may be associated with atherosclerosis and vascular disease. Macrophages are a major component of atherosclerotic plaque, and classically activated (M1) macrophages contribute to plaque instability. Our goal was to identify plasma biomarkers that reflect macrophage inflammation and are associated with subclinical atherosclerosis. APPROACH AND RESULTS: We tested whether M1 macrophages produce galectin-3-binding protein in vitro. Then, we measured galectin-3-binding protein and the soluble macrophage biomarkers soluble cluster of differentiation (CD) 163 and soluble CD14 in 264 participants in the Women's Interagency HIV Study. Women were positive for HIV, HCV, both, or neither (66 in each group, matched for age, race/ethnicity, and smoking status). Carotid artery disease was assessed by ultrasound measurement of right distal common carotid artery intima-media thickness, distensibility, and presence of atherosclerotic lesions (intima-media thickness >1.5 mm). Plasma galectin-3-binding protein was higher in HCV+ than HCV- women (P<0.01) but did not differ by HIV status. The 3 inflammatory macrophage markers were significantly correlated with each other and negatively correlated with CD4+ counts in HIV-infected women. We defined a macrophage score as 1, 2, or 3 biomarkers elevated above the median. In models adjusted for traditional risk factors, higher macrophage scores were significantly associated with increased atherosclerotic lesions and lower carotid distensibility. Receiver-operator curve analysis of lesions revealed that the markers added predictive value beyond traditional risk factors and C-reactive protein. CONCLUSIONS: The macrophage inflammatory markers galectin-3-binding protein, soluble CD163, and soluble CD14 are significantly associated with carotid artery disease in the setting of HIV and HCV infection.


Assuntos
Doenças das Artérias Carótidas/sangue , Coinfecção , Infecções por HIV/sangue , Hepatite C/sangue , Mediadores da Inflamação/sangue , Macrófagos/metabolismo , Adulto , Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Antígenos de Neoplasias/sangue , Doenças Assintomáticas , Biomarcadores/sangue , Biomarcadores Tumorais/sangue , Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/imunologia , Espessura Intima-Media Carotídea , Proteínas de Transporte/sangue , Estudos Transversais , Feminino , Glicoproteínas/sangue , Infecções por HIV/diagnóstico , Infecções por HIV/imunologia , Hepatite C/diagnóstico , Hepatite C/imunologia , Humanos , Receptores de Lipopolissacarídeos/sangue , Macrófagos/imunologia , Pessoa de Meia-Idade , Receptores de Superfície Celular/sangue , Fatores de Risco , Fatores Sexuais , Fumar/sangue , Fumar/imunologia , Rigidez Vascular
9.
BMC Public Health ; 15: 1277, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26695971

RESUMO

BACKGROUND: Effective treatment of HIV since 1996 has reduced morbidity and mortality through virologic suppression. Combination antiretroviral therapy (cART) has been recognized as key to the prevention of drug resistance and the transmission of infection. We used eighteen years of virologic outcomes in a long-standing cohort of women to describe longitudinal viral load trajectories; and examine factors associated with sustained viremia and mortality. METHODS: We analyzed data from DC WIHS women with > four semiannual visits using a group-based logistic trajectory analysis approach to identify patterns of HIV RNA detection (>80 copies/mL or lower assay limit, and >1000 copies/mL). We verified findings using cumulative viral load suppression-years, explored group characteristics using generalized linear modeling with generalized estimating equations for repeated measures, and examined survival using the Kaplan-Meier and Cox proportional hazard analyses. RESULTS: 329 women contributed 6633 visits between 1994 and 2012 and demonstrated high, moderate, and low probability patterns of HIV RNA detection (>80 copies/mL) in 40.7, 35.6, and 23.7% of participant visits, respectively. Analysis of cumulative years of viral load suppression supported these observations. Kaplan-Meier survival analysis demonstrated high mortality of 31.1% with sustained viremia, but no significant difference in mortality between intermittent viremia and non-viremia patterns, 6.9 and 4.9% respectively. Mortality was associated with higher age, lower CD4+ T lymphocyte count, and sustained viremia by Cox multivariate analysis. CONCLUSIONS: This ecologic study demonstrates the effectiveness of viral suppression, and conversely the association between viremia and mortality. In community delivery of cART for HIV care, distinct patterns of sustained viremia, intermittent viremia, and non-viremia were identified over nearly 18 years in the DC WIHS, capturing the dynamics and complexity of sustaining long-term HIV care. Persistent viremia was associated with lower CD4s and mortality, but surprisingly mortality was not different between continuous suppression and intermittent viremia. Classification of long-term virologic patterns such as these observed HIV treatment "careers" may provide a suitable framework to identify modifiable factors associated with treatment resilience and failure. Both individual and population interventions are needed to reduce transmission, prevent the emergence of drug resistance, and improve outcomes of community ART programs.


Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , RNA Viral/sangue , Viremia/tratamento farmacológico , Viremia/epidemiologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Linfócitos T CD4-Positivos/efeitos dos fármacos , District of Columbia/epidemiologia , Farmacorresistência Viral , Feminino , Infecções por HIV/virologia , Humanos , Pessoa de Meia-Idade , Carga Viral , Adulto Jovem
10.
Sci Total Environ ; 890: 164430, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37247743

RESUMO

The role of macroalgae (seaweed) as a global contributor to carbon drawdown within marine sediments - termed 'blue carbon' - remains uncertain and controversial. While studies are needed to validate the potential for macroalgal­carbon sequestration in marine and coastal sediments, fundamental questions regarding the fate of dislodged macroalgal biomass need to be addressed. Evidence suggests macroalgal biomass may be advected and deposited within other vegetated coastal ecosystems and down to the deep ocean; however, contributions to near-shore sediments within coastal waters remain uncertain. In this study a combination of eDNA metabarcoding and surficial sediment sampling informed by seabed mapping from different physical environments was used to test for the presence of macroalgal carbon in near-shore coastal sediments in south-eastern Australia, and the physical factors influencing patterns of macroalgal transport and deposition. DNA products for a total of 68 macroalgal taxa, representing all major macroalgal groups (Phaeophyceae, Rhodophyta, and Chlorophyta) were successfully detected at 112 near-shore locations. These findings confirm the potential for macroalgal biomass to be exported into near-shore sediments and suggest macroalgal carbon donors could be both speciose and diverse. Modelling suggested that macroalgal transport and deposition, and total organic carbon (TOC), are influenced by complex interactions between several physical environmental factors including water depth, sediment grain size, wave orbital velocity, current speed, current direction, and the extent of the infralittoral zone around depositional areas. Extrapolation of the optimised model was used to predict spatial patterns of macroalgal deposition and TOC across the coastline and to identify potentially important carbon sinks. This study builds on recent studies providing empirical evidence for macroalgal biomass deposits in near-shore sediments, and a framework for predicting the spatial distribution of potential carbon sinks and informing future surveys aimed at determining the potential for long-term macroalgal carbon sequestration in marine sediments.


Assuntos
Clorófitas , Rodófitas , Alga Marinha , Ecossistema , Carbono , Sedimentos Geológicos
11.
J Virol ; 85(20): 10826-33, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21849458

RESUMO

While the human leukocyte antigen (HLA) genotype has been associated with the rate of HIV disease progression in untreated patients, little is known regarding these relationships in patients using highly active antiretroviral therapy (HAART). The limited data reported to date identified few HLA-HIV disease associations in patients using HAART and even occasional associations that were opposite of those found in untreated patients. We conducted high-resolution HLA class I and II genotyping in a random sample (n = 860) of HIV-seropositive women enrolled in a long-term cohort initiated in 1994. HLA-HIV disease associations before and after initiation of HAART were examined using multivariate analyses. In untreated HIV-seropositive patients, we observed many of the predicted associations, consistent with prior studies. For example, HLA-B*57 (ß = -0.7; 95% confidence interval [CI] = -0.9 to -0.5; P = 5 × 10⁻¹¹) and Bw4 (ß = -0.2; 95% CI = -0.4 to -0.1; P = 0.009) were inversely associated with baseline HIV viral load, and B*57 was associated with a low risk of rapid CD4+ decline (odds ratio [OR] = 0.2; 95% CI = 0.1 to 0.6; P = 0.002). Conversely, in treated patients, the odds of a virological response to HAART were lower for B*57:01 (OR = 0.2; 95% CI = 0.0 to 0.9; P = 0.03), and Bw4 (OR = 0.4; 95% CI = 0.1 to 1.0; P = 0.04) was associated with low odds of an immunological response. The associations of HLA genotype with HIV disease are different and sometimes even opposite in treated and untreated patients.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Antígenos HLA/genética , Adulto , Contagem de Linfócito CD4 , Progressão da Doença , Feminino , Genótipo , Humanos , Carga Viral
12.
J Infect Dis ; 203(12): 1807-14, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21606539

RESUMO

BACKGROUND: Human leukocyte antigen (HLA) class I and II genotype is associated with clearance of hepatitis C virus (HCV) infection, but little is known regarding its relation with HCV viral load or risk of liver disease in patients with persistent HCV infection. METHODS: High-resolution HLA class I and II genotyping was conducted in a prospective cohort of 519 human immunodeficiency virus (HIV)-seropositive and 100 HIV-seronegative women with persistent HCV infection. The end points were baseline HCV viral load and 2 noninvasive indexes of liver disease, fibrosis-4 (FIB-4), and the aspartate aminotransferase to platelet ratio index (APRI), measured at baseline and prospectively. RESULTS: DQB1*0301 was associated with low baseline HCV load (ß = -.4; 95% confidence interval [CI], -.6 to -.3; P < .00001), as well as with low odds of FIB-4-defined (odds ratio [OR], .5; 95% CI, .2-.9; P = .02) and APRI-defined liver fibrosis (OR, .5; 95% CI, .3-1.0; P = .06) at baseline and/or during follow-up. Most additional associations with HCV viral load also involved HLA class II alleles. Additional associations with FIB-4 and APRI primarily involved class I alleles, for example, the relation of B*1503 with APRI-defined fibrosis had an OR of 2.0 (95% CI, 1.0-3.7; P = .04). CONCLUSIONS: HLA genotype may influence HCV viral load and risk of liver disease, including DQB1*0301, which was associated with HCV clearance in prior studies.


Assuntos
Infecções por HIV/complicações , Antígenos HLA/genética , Hepacivirus/patogenicidade , Hepatite C Crônica/virologia , Cirrose Hepática/genética , Carga Viral/genética , Adulto , Alanina Transaminase/sangue , Alelos , Aspartato Aminotransferases/sangue , Estudos de Coortes , Feminino , Genótipo , Antígenos HLA-DQ/genética , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/virologia , Modelos Logísticos , Contagem de Plaquetas , Estudos Prospectivos , Estados Unidos
13.
Hepatology ; 51(5): 1514-22, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20169624

RESUMO

UNLABELLED: Studies of human leukocyte antigen (HLA) alleles and their relation with hepatitis C virus (HCV) viremia have had conflicting results. However, these studies have varied in size and methods, and few large studies assessed HLA class I alleles. Only one study conducted high-resolution class I genotyping. The current investigation therefore involved high-resolution HLA class I and II genotyping of a large multiracial cohort of U.S. women with a high prevalence of HCV and HIV. Our primary analyses evaluated associations between 12 HLA alleles identified through a critical review of the literature and HCV viremia in 758 HCV-seropositive women. Other alleles with >5% prevalence were also assessed; previously unreported associations were corrected for multiple comparisons. DRB1*0101 (prevalence ratio [PR] = 1.7; 95% confidence interval [CI] = 1.1-2.6), B*5701 (PR=2.0; 95% CI = 1.0-3.1), B*5703 (PR = 1.7; 95% CI = 1.0-2.5), and Cw*0102 (PR = 1.9; 95% CI = 1.0-3.0) were associated with the absence of HCV RNA (i.e., HCV clearance), whereas DRB1*0301 (PR = 0.4; 95% CI = 0.2-0.7) was associated with HCV RNA positivity. DQB1*0301 was also associated with the absence of HCV RNA but only among HIV-seronegative women (PR = 3.4; 95% CI = 1.2-11.8). Each of these associations was among those predicted. We additionally studied the relation of HLA alleles with HCV infection (serostatus) in women at high risk of HCV from injection drug use (N = 838), but no significant relationships were observed. CONCLUSION: HLA genotype influences the host capacity to clear HCV viremia. The specific HLA associations observed in the current study are unlikely to be due to chance because they were a priori hypothesized.


Assuntos
Hepatite C Crônica/virologia , Hepatite C/virologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Viremia/imunologia , Adulto , Alelos , Estudos de Coortes , Feminino , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C Crônica/imunologia , Humanos , Pessoa de Meia-Idade , RNA Viral/análise , Abuso de Substâncias por Via Intravenosa
14.
J Infect Dis ; 201(6): 823-34, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20151840

RESUMO

BACKGROUND: Because activation of T cells is associated with human immunodeficiency virus (HIV) pathogenesis, CD4 and CD8 activation levels in patients coinfected with HIV and hepatitis C virus (HCV) may explain conflicting reports regarding effects of HCV on HIV disease progression. METHODS: Kaplan-Meier and multivariate Cox regression models were used to study the risk of incident clinical AIDS and AIDS-related deaths among 813 HCV-negative women with HIV infection, 87 HCV-positive nonviremic women with HIV coinfection, and 407 HCV-positive viremic women with HIV coinfection (median follow-up time, 5.2 years). For 592 women, the percentages of activated CD4 and CD8 T cells expressing HLA-DR (DR) and/or CD38 were evaluated. RESULTS: HCV-positive viremic women had a statistically significantly higher percentage of activated CD8 T cells (P < .001) and a statistically significantly higher incidence of AIDS compared with HCV-negative women (P < .001 [log-rank test]). The AIDS risk was greater among HCV-positive viremic women in the highest tertile compared with the lowest tertile (>43% vs <26%) of CD8(+)CD38(+)DR(+) T cells (hazard ratio, 2.94 [95% confidence interval, 1.50-5.77]; P = .001). This difference was not observed in the HCV-negative women (hazard ratio, 1.87 [95% confidence interval, 0.80-4.35]; P = .16). In contrast, CD4 activation predicted AIDS in both groups similarly. Increased percentages of CD8(+)CD38(-)DR(+), CD4(+)CD38(-)DR(-), and CD8(+)CD38(-)DR(-) T cells were associated with a >60% decreased risk of AIDS for HCV-positive viremic women and HCV-negative women. CONCLUSION: HCV-positive viremic women with HIV coinfection who have high levels of T cell activation may have increased risk of AIDS. Earlier treatment of HIV and HCV infection may be beneficial.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/imunologia , Linfócitos T CD8-Positivos/imunologia , Hepatite C/complicações , Hepatite C/imunologia , Ativação Linfocitária , Síndrome da Imunodeficiência Adquirida/sangue , Adolescente , Adulto , Contagem de Linfócito CD4 , Progressão da Doença , Feminino , HIV/genética , HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/complicações , Infecções por HIV/imunologia , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/sangue , Humanos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , RNA Viral/sangue , Fatores de Risco , Estados Unidos/epidemiologia , Saúde da Mulher , Adulto Jovem
15.
Sci Total Environ ; 800: 149573, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34399348

RESUMO

To help mitigate the impacts of climate change, many nature-based solutions are being explored. These solutions involve protection and restoration of ecosystems that serve as efficient carbon sinks, including vegetated coastal ecosystems (VCEs: tidal marshes, mangrove forests, and seagrass meadows) also known as 'Blue Carbon' ecosystems. In fact, many nations are seeking to manage VCEs to help meet their climate change mitigation targets through Nationally Determined Contributions (NDCs). However, incorporation of VCEs into NDCs requires national-scale estimates of contemporary and future blue carbon storage, which has not yet been achieved. Here we address this challenge using machine learning approaches to reliably map (with 62-72% accuracy) soil carbon stocks in VCEs based on geospatial data (topography, geomorphology, climate, and anthropogenic impacts), using Australia as a case study. The resulting maps of soil carbon stocks showed that there is a total of 951 Tg (±65 Tg) of carbon stock within Australian VCEs. Strong relationships between soil carbon stocks and climatic conditions (temperature, rainfall, solar radiation) allowed us to project future changes in carbon storage across all RCP scenarios for the years 2050 and 2090 to determine changes in environmental suitability for soil carbon stocks. Results show that soil carbon stocks in mangrove/tidal marsh ecosystems are likely to predominantly experience declines in carbon stocks under predicted climate change scenarios (19% of ecosystems area is predicted to have an increase in soil carbon stocks, while 38% of ecosystems area is predicted to have a decrease in soil carbon stocks), but a majority of seagrass area is likely to have increased soil carbon stocks (56% increase, 7% decrease). This approach is effective for developing robust national blue carbon inventories and revealing the capacity for blue carbon to help meet NDCs. The resulting spatially-explicit maps can also be used to pinpoint areas for successful blue carbon projects both now and in the future.


Assuntos
Carbono , Ecossistema , Austrália , Carbono/análise , Sequestro de Carbono , Áreas Alagadas
16.
Sci Total Environ ; 710: 134680, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31927279

RESUMO

Coastal and estuarine ecosystems, such as mangroves, tidal marshes and seagrass meadows, provide a range of ecosystem services, but have seen extensive degradation and decline. Effective protection and rehabilitation of coastal ecosystems requires an understanding of how efforts may improve associated ecosystem services. In this study, we present a spatially-explicit angler catch function to predict boat-based recreational catch as a function of ecosystem and angler characteristics. We developed a choice model to investigate where recreational anglers launch their boats and fish in southeast Australia. By linking the recreational catch models with a choice model, we were able to quantify welfare gains of ecosystem rehabilitation. We found welfare gains across fishing locations varied widely due to heterogeneous coverage of seagrass. The welfare gains of different fishing locations ranged from near-zero in areas of low seagrass coverage, to AU $19.18 (10% increase in seagrass area) and to AU $85.55 (30% increase) per trip in location of high seagrass coverage. Given two million fishing trips occurring per year in Port Phillip Bay, and one million in Western Port, the aggregated welfare gain could scale up to AU $6.2 million with a 10% increase in seagrass coverage, and AU $22 million per annum with a 30% increase in seagrass. We also calculated the welfare loss associated with total loss of seagrass ecosystem in each fishing location to represent the current value, which varied significantly, ranging from near-zero in some locations to AU $87.47 per trip in other locations. Over the past several decades, the bay-wide seagrass ecosystem has dropped by 36.7% in Western Port, resulting in potential welfare loss of an estimated AU $ 86.7 million per annum. Our analyses provide insightful spatial policy implications for coastal and marine ecosystem rehabilitation in the region.

17.
Clin Infect Dis ; 49(1): 148-54, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19480573

RESUMO

BACKGROUND: Isolated antibody to hepatitis B core antigen (anti-HBc) is a common serologic finding in persons infected with human immunodeficiency virus (HIV), but the outcome and clinical significance are uncertain. METHODS: We performed repeated hepatitis B virus (HBV) serologic tests on women who participated in the Women's Interagency HIV Study and who had isolated anti-HBc at study entry. RESULTS: Repeated serologic tests were performed for 322 women (282 HIV-infected and 40 HIV-uninfected) at a median of 7.5 years after study entry. Seventy-one percent of women retained isolated anti-HBc serologic status, 20% acquired antibody to hepatitis B surface antigen (anti-HBs), and 2% acquired hepatitis B surface antigen (HBsAg). In unadjusted analysis, increasing age, injection drug use, and hepatitis C viremia were negatively associated with acquisition of anti-HBs. For HIV-infected women, predictors of acquisition of anti-HBs were an increase in CD4 cell count and the use of highly active antiretroviral therapy (HAART). Receipt of drugs with activity against HBV and self-reported HBV vaccination did not predict anti-HBs acquisition. In the multivariable regression model, HAART use remained a significant predictor of anti-HBs acquisition, whereas women with hepatitis C viremia were more likely to retain isolated anti-HBc serologic status. CONCLUSIONS: Isolated anti-HBc status remained stable over time for the majority of women, especially women with chronic hepatitis C virus infection. Development of anti-HBs was predicted by HAART use and an increase in CD4 cell count. We conclude that a proportion of HIV-infected women with isolated anti-HBc have prior natural HBV infection with anti-HBs that is at an undetectable level because of immune dysfunction. Isolated anti-HBc in the presence of chronic hepatitis C virus infection may be attributable to a different phenomenon, such as dysfunctional antibody production.


Assuntos
Infecções por HIV/complicações , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Humanos , Estudos Longitudinais
18.
J Acquir Immune Defic Syndr ; 81(3): 274-283, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30893126

RESUMO

BACKGROUND: HIV-infected (HIV+) women seem to be more vulnerable to neurocognitive impairment (NCI) than HIV+ men, perhaps in part due to mental health factors. We assessed the association between elevated depressive symptoms and NCI among HIV+ and HIV-uninfected (HIV-) women and men. SETTING: Women's Interagency HIV Study and Multicenter AIDS Cohort Study. METHODS: Eight hundred fifty-eight HIV+ (429 women; 429 men) and 562 HIV- (281 women; 281 men) completed the Center for Epidemiologic Studies Depression (16 cutoff) Scale and measures of psychomotor speed/attention, executive, and motor function over multiple visits (or time points). Women's Interagency HIV Study and Multicenter AIDS Cohort Study participants were matched according to HIV status, age, race/ethnicity, and education. Generalized linear mixed models were used to examine interactions between biological sex, HIV serostatus, and depression on impairment (T-scores <40) after covariate adjustment. RESULTS: Despite a higher frequency of depression among men, the association between depression and executive function differed by sex and HIV serostatus. HIV+ women with depression had 5 times the odds of impairment on a measure of executive control and inhibition versus HIV- depressed women and 3 times the odds of impairment on that measure versus HIV+ depressed men. Regardless of group status, depression was associated with greater impairment on processing speed, executive (mental flexibility), and motor function (P's < 0.05). CONCLUSIONS: Depression contributes to NCI across a broad range of cognitive domains in HIV+ and HIV- individuals, but HIV+ depressed women show greater vulnerabilities in executive function. Treating depression may help to improve cognition in patients with HIV infection.


Assuntos
Depressão/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/psicologia , Adulto , Fatores Etários , Idoso , Cognição , Estudos de Coortes , Etnicidade , Função Executiva , Feminino , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Fatores Raciais , Fatores Sexuais , Estados Unidos , Adulto Jovem
19.
J Acquir Immune Defic Syndr ; 79(1): 101-107, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29847476

RESUMO

BACKGROUND: Women may be more vulnerable to HIV-related cognitive dysfunction compared with men because of sociodemographic, lifestyle, mental health, and biological factors. However, studies to date have yielded inconsistent findings on the existence, magnitude, and pattern of sex differences. We examined these issues using longitudinal data from 2 large, prospective, multisite, observational studies of US women and men with and without HIV. SETTING: The Women's Interagency HIV Study (WIHS) and Multicenter AIDS Cohort Study (MACS). METHODS: HIV-infected (HIV+) and uninfected (HIV-) participants in the Women's Interagency HIV Study and Multicenter AIDS Cohort Study completed tests of psychomotor speed, executive function, and fine motor skills. Groups were matched on HIV status, sex, age, education, and black race. Generalized linear mixed models were used to examine group differences on continuous and categorical demographically corrected T-scores. Results were adjusted for other confounding factors. RESULTS: The sample (n = 1420) included 710 women (429 HIV+) and 710 men (429 HIV+) (67% non-Hispanic black; 53% high school or less). For continuous T-scores, sex by HIV serostatus interactions were observed on the Trail Making Test parts A & B, Grooved Pegboard, and Symbol Digit Modalities Test. For these tests, HIV+ women scored lower than HIV+ men, with no sex differences in HIV- individuals. In analyses of categorical scores, particularly the Trail Making Test part A and Grooved Pegboard nondominant, HIV+ women also had a higher odds of impairment compared with HIV+ men. Sex differences were constant over time. CONCLUSIONS: Although sex differences are generally understudied, HIV+ women vs men show cognitive disadvantages. Elucidating the mechanisms underlying these differences is critical for tailoring cognitive interventions.


Assuntos
Cognição , Infecções por HIV/psicologia , Fatores Sexuais , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos
20.
AIDS ; 21(14): 1933-41, 2007 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-17721101

RESUMO

OBJECTIVE: Cutaneous anergy testing evaluates delayed type hypersensitivity responses and is, in essence, an in-vivo measure of cell-mediated immune function at an epithelial surface. This study assessed the relationship of anergy test results with cervical infection by human papillomavirus (HPV) and cervical neoplasia in HIV-seropositive and seronegative women. METHODS: HIV-seropositive (n = 1029) and HIV-seronegative (n = 272) women enrolled in a long-term cohort study were followed semi-annually with HPV-DNA testing and cytology. Anergy was defined as unresponsiveness to Candida albicans, tetanus toxoid, and mumps antigen. RESULTS: Anergy was associated with the prevalent detection of squamous intraepithelial lesions [SIL; adjusted odds ratio 1.70; 95% confidence interval (CI) 1.16-2.48] in multivariable logistic regression models, and with the incident detection of oncogenic HPV (adjusted hazard ratio 1.24; 95% CI 0.99-1.56) in multivariable Cox regression models. These models adjusted for HIV infection, combined CD4 T-cell and HIV-RNA strata (13 separate strata to control optimally for their interactive effects), as well as other variables. CONCLUSION: Cutaneous anergy testing may measure aspects of local cellular immune function in epithelial tissues that are important for the control of HPV and development of SIL, and that in HIV-seropositive women are not fully accounted for by circulating CD4 T-cell counts and HIV-RNA levels.


Assuntos
Soropositividade para HIV/imunologia , Hipersensibilidade Tardia/imunologia , Infecções por Papillomavirus/imunologia , Doenças do Colo do Útero/imunologia , Neoplasias do Colo do Útero/imunologia , Adulto , Contagem de Linfócito CD4 , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/imunologia , Feminino , Soronegatividade para HIV/imunologia , Soropositividade para HIV/complicações , Soropositividade para HIV/epidemiologia , Humanos , Hipersensibilidade Tardia/complicações , Hipersensibilidade Tardia/epidemiologia , Imunidade Celular/imunologia , Incidência , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Prevalência , Estudos Prospectivos , RNA Viral/análise , Pele/imunologia , Doenças do Colo do Útero/complicações , Doenças do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/complicações , Neoplasias do Colo do Útero/epidemiologia , Displasia do Colo do Útero/complicações , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/imunologia
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