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1.
Gen Comp Endocrinol ; 328: 114106, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35973588

RESUMO

Neurosecretory staining in the pleural-pedal ganglion of the Japanese abalone (ezoawabi), Haliotis discus hannai, was studied during the reproductive cycle. The variation in stain affinity of the cells and amount of neurosecretory material contained in the neurosecretory cells were measured during the study. The pleural-pedal ganglion contained 7 different cell types. The quantity of different cell types in the pleural-pedal ganglion was unusual for a prosobranch gastropod. Cell Types, α- and ß-cells, showed neurosecretory staining and the stain intensity varied during the reproductive cycle. α-cells were the most abundant cells in the pleural-pedal ganglion and the quantity of neurosecretory material inside the cell body clearly correlated with gametogenesis. Neurosecretory material in ß-cells showed a strong correlation with the induction of spawning. A neurohemal organ (pleural organ) was found in close proximity to the ß-cells in the statocyst tissue. The pleural organ is the first ectodermal neurohemal organ reported in a prosobranch gastropod. A nervous connection (stato-pleural nerve) with a possible sensory function was found between the statocyst and the pleural-pedal ganglion.


Assuntos
Órgãos Circunventriculares , Gastrópodes , Animais , Japão , Reprodução , Coloração e Rotulagem
2.
HIV Med ; 22(4): 283-293, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33215809

RESUMO

BACKGROUND: In a 2013 survey, we reported distinct discrepancies in delivery of tuberculosis (TB) and HIV services in eastern Europe (EE) vs. western Europe (WE). OBJECTIVES: To verify the differences in TB and HIV services in EE vs. WE. METHODS: Twenty-three sites completed a survey in 2018 (EE, 14; WE, nine; 88% response rate). Results were compared across as well as within the two regions. When possible, results were compared with the 2013 survey. RESULTS: Delivery of healthcare was significantly less integrated in EE: provision of TB and HIV services at one site (36% in EE vs. 89% in WE; P = 0.034), and continued TB follow-up in one location (42% vs. 100%; P = 0.007). Although access to TB diagnostics, standard TB and HIV drugs was generally good, fewer sites in EE reported unlimited access to rifabutin/multi-drug-resistant TB (MDR-TB) drugs, HIV integrase inhibitors and opioid substitution therapy (OST). Compared with 2013, routine usage of GeneXpert was more common in EE in 2018 (54% vs. 92%; P = 0.073), as was access to moxifloxacin (46% vs. 91%; P = 0.033), linezolid (31% vs. 64%; P = 0.217), and bedaquiline (0% vs. 25%; P = 0.217). Integration of TB and HIV services (46% vs. 39%; P = 1.000) and provision of OST to patients with opioid dependency (54% vs. 46%; P = 0.695) remained unchanged. CONCLUSION: Delivery of TB and HIV healthcare, including integration of TB and HIV care and access to MDR-TB drugs, still differs between WE and EE, as well as between individual EE sites.


Assuntos
Infecções por HIV , Tuberculose , Antituberculosos/uso terapêutico , Atenção à Saúde , Europa (Continente)/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico
3.
J Exp Biol ; 224(12)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34109419

RESUMO

Signal plasticity can maximize the usefulness of costly animal signals such as the electric organ discharges (EODs) of weakly electric fishes. Some species of the order Gymnotiformes rapidly alter their EOD amplitude and duration in response to circadian cues and social stimuli. How this plasticity is maintained across related species with different degrees of signal complexity is poorly understood. In one genus of weakly electric gymnotiform fish (Brachyhypopomus), only one species, B. bennetti, produces a monophasic signal while all other species emit complex biphasic or multiphasic EOD waveforms produced by two overlapping but asynchronous action potentials in each electric organ cell (electrocyte). One consequence of this signal complexity is the suppression of low-frequency signal content that is detectable by electroreceptive predators. In complex EODs, reduction of the EOD amplitude and duration during daytime inactivity can decrease both predation risk and the metabolic cost of EOD generation. We compared EOD plasticity and its underlying physiology in Brachyhypopomus focusing on B. bennetti. We found that B. bennetti exhibits minimal EOD plasticity, but that its electrocytes retained vestigial mechanisms of biphasic signaling and vestigial mechanisms for modulating the EOD amplitude. These results suggest that this species represents a transitional phenotypic state within a clade where signal complexity and plasticity were initially gained and then lost. Signal mimicry, mate recognition and sexual selection are potential factors maintaining the monophasic EOD phenotype in the face of detection by electroreceptive predators.


Assuntos
Peixe Elétrico , Gimnotiformes , Potenciais de Ação , Animais , Órgão Elétrico , Transdução de Sinais
4.
HIV Med ; 21(10): 617-624, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32885559

RESUMO

BACKGROUND: The European AIDS Clinical Society (EACS) Guidelines cover key aspects of HIV management with major updates every two years. GUIDELINE HIGHLIGHTS: The 2019 Guidelines were extended with a new section focusing on drug-drug interactions and other prescribing issues in people living with HIV (PLWH). The recommendations for treatment-naïve PLWH were updated with four preferred regimens favouring unboosted integrase inhibitors. A two-drug regimen with dolutegravir and lamivudine, and a three-drug regimen including doravirine were also added to the recommended initial regimens. Lower thresholds for hypertension were expanded to all PLWH and for cardiovascular disease prevention, the 10-year predicted risk threshold for consideration of antiretroviral therapy (ART) modification was lowered from 20% to 10%. Frailty and obesity were added as new topics. It was specified to use urine albumin to creatinine ratio to screen for glomerular disease and urine protein to creatinine ratio for tubular diseases, and thresholds were streamlined with the Kidney Disease: Improving Global Outcomes (KDIGO) recommendations. Hepatitis C virus (HCV) treatment recommendations were split into preferred and alternative treatment options. The algorithm for management of recently acquired HCV infection was updated and includes recommendations for early chronic infection management. Treatment of resistant tuberculosis (TB) was streamlined with the World Health Organization (WHO) recommendations, and new tables on immune reconstitution inflammatory syndrome, on when to start ART in the presence of opportunistic infections and on TB drug dosing were included. CONCLUSIONS: The EACS Guidelines underwent major revisions of all sections in 2019. They are available in four different formats including a new interactive web-based version and are translated into Chinese, French, German, Japanese, Portuguese, Russian and Spanish.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/uso terapêutico , Fatores Etários , Comorbidade , Interações Medicamentosas , Quimioterapia Combinada , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Humanos , Lamivudina/uso terapêutico , Oxazinas/uso terapêutico , Piperazinas/uso terapêutico , Piridonas/uso terapêutico , Resultado do Tratamento , Triazóis/uso terapêutico
5.
HIV Med ; 21(2): 71-83, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31647187

RESUMO

The EuroSIDA study was initiated in 1994 and follows adult people living with HIV (PLHIV) in 100 collaborating clinics across 35 countries covering all European regions, Israel and Argentina. The study aims to study the long-term virological, immunological and clinical outcomes of PLHIV and to monitor temporal changes and regional differences in outcomes across Europe. Annually collected data include basic demographic characteristics, information on AIDS- and non-AIDS-related clinical events, and details about antiretroviral therapy (ART), hepatitis C treatment and other medications, in addition to a range of laboratory values. The summer 2016 data set held data from a total of 23 071 individuals contributing 174 481 person-years of follow-up, while EuroSIDA's unique plasma repository held over 160 000 samples. Over the past 25 years, close to 300 articles have been published in peer-reviewed journals (h-index 52), covering a range of scientific focus areas, including monitoring of clinical and virological outcomes, ART uptake, efficacy and adverse events, the influence of hepatitis virus coinfection, variation in the quality of HIV care and management across settings and regions, and biomarker research. Recognizing that there remain unresolved issues in the clinical care and management of PLHIV in Europe, EuroSIDA was one of the cohorts to found The International Cohort Consortium of Infectious Disease (RESPOND) cohort consortium on infectious diseases in 2017. In celebration of the EuroSIDA study's 25th anniversary, this article aims to summarize key scientific findings and outline current and future scientific focus areas.


Assuntos
Infecções por HIV/tratamento farmacológico , HIV/imunologia , Hepatite C/tratamento farmacológico , RNA Viral/genética , Argentina , Contagem de Linfócito CD4 , Coinfecção , Europa (Continente) , Feminino , HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Israel , Perda de Seguimento , Masculino , Estudos Multicêntricos como Assunto , Resultado do Tratamento , Carga Viral
6.
Oecologia ; 194(1-2): 177-191, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32940775

RESUMO

Body size, trophic position (TP), and trophic niche width are important elements of food webs; however, there is still debate regarding their interrelationships. Most studies have tested these correlations using datasets restricted to carnivores and bivariate models that disregard potential indirect effects of other factors, their interactions, and phylogeny. We analyzed relationships among TP, consumer size, maximum food item size, food item size variation (a proxy for trophic niche width), and two other traits (gut length and mouth width) using confirmatory path analysis of an extensive dataset for freshwater fishes that encompass both carnivorous and non-carnivorous species. Consumer size was associated with maximum food size, food size variation, mouth width, and gut length, all of which mediated indirect relationships between body size and TP. Mouth gape was associated with maximum food size, and consumers that fed on larger food items had higher TP. Consumers with relatively long guts generally fed on small and homogeneous food items near the base of the food web. Models were consistent whether or not accounting for phylogeny, but varied according to trophic guilds. However, the body size of both carnivorous and non-carnivorous was not directly associated with TP. Therefore, the incorporation of functional traits and their intermediate pathways is critical for understanding size-based trophic relationships of animals that encompass diverse feeding strategies. Our results caution approaches that rely on body size as a surrogate for TP, especially in systems where plants and detritus are consumed directly by a significant number of animals, such as in most freshwater ecosystems.


Assuntos
Ecossistema , Cadeia Alimentar , Animais , Tamanho Corporal , Carnivoridade , Peixes , Comportamento Predatório
7.
HIV Med ; 19(5): 309-315, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29493093

RESUMO

BACKGROUND: The European AIDS Clinical Society (EACS) Guidelines have since 2005 provided multidisciplinary recommendations for the care of HIV-positive persons in geographically diverse areas. GUIDELINE HIGHLIGHTS: Major revisions have been made in all sections of the 2017 Guidelines: antiretroviral treatment (ART), comorbidities, coinfections and opportunistic diseases. Newly added are also a summary of the main changes made, and direct video links to the EACS online course on HIV Management. Recommendations on the clinical situations in which tenofovir alafenamide may be considered over tenofovir disoproxil fumarate are provided, and recommendations on which antiretrovirals can be used safely during pregnancy have been revised. Renal and bone toxicity and hepatitis C virus (HCV) treatment have been added as potential reasons for ART switches in fully virologically suppressed individuals, and dolutegravir/rilpivirine has been included as a treatment option. In contrast, dolutegravir monotherapy is not recommended. New recommendations on non-alcoholic fatty liver disease, chronic lung disease, solid organ transplantation, and prescribing in elderly are included, and human papilloma virus (HPV) vaccination recommendations have been expanded. All drug-drug interaction tables have been updated and new tables are included. Treatment options for direct-acting antivirals (DAAs) have been updated and include the latest combinations of sofosbuvir/velpatasvir/voxilaprevir and glecaprevir/pibrentasvir. Recommendations on management of DAA failure and acute HCV infection have been expanded. For treatment of tuberculosis (TB), it is underlined that intermittent treatment is contraindicated, and for resistant TB new data suggest that using a three-drug combination may be as effective as a five-drug regimen, and may reduce treatment duration from 18-24 to 6-10 months. CONCLUSIONS: Version 9.0 of the EACS Guidelines provides a holistic approach to HIV care and is translated into the six most commonly spoken languages.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Adulto , Antirretrovirais/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Coinfecção/tratamento farmacológico , Interações Medicamentosas , Europa (Continente) , Feminino , Humanos , Masculino , Guias de Prática Clínica como Assunto , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Sociedades Científicas
8.
HIV Med ; 19(9): 605-618, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30019813

RESUMO

OBJECTIVES: Previous studies have suggested that hypertension in HIV-positive individuals is associated primarily with traditional risk factors such as older age, diabetes and dyslipidaemia. However, controversy remains as to whether exposure to antiretroviral (ARV) drugs poses additional risk, and we investigated this question in the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) cohort. METHODS: The incidence of hypertension [systolic blood pressure (BP) > 140 and/or diastolic BP > 90 mmHg and/or initiation of antihypertensive treatment] was determined overall and in strata defined by demographic, metabolic and HIV-related factors, including cumulative exposure to each individual ARV drug. Predictors of hypertension were identified using uni- and multivariable Poisson regression models. RESULTS: Of 33 278 included persons, 7636 (22.9%) developed hypertension over 223 149 person-years (PY) [incidence rate: 3.42 (95% confidence interval (CI) 3.35-3.50) per 100 PY]. In univariable analyses, cumulative exposure to most ARV drugs was associated with an increased risk of hypertension. After adjustment for demographic, metabolic and HIV-related factors, only associations for nevirapine [rate ratio 1.07 (95% CI: 1.04-1.13) per 5 years] and indinavir/ritonavir [rate ratio 1.12 (95% CI: 1.04-1.20) per 5 years] remained statistically significant, although effects were small. The strongest independent predictors of hypertension were male gender, older age, black African ethnicity, diabetes, dyslipidaemia, use of lipid-lowering drugs, high body mass index (BMI), renal impairment and a low CD4 count. CONCLUSIONS: We did not find evidence for any strong independent association between exposure to any of the individual ARV drugs and the risk of hypertension. Findings provide reassurance that screening policies and preventative measures for hypertension in HIV-positive persons should follow algorithms used for the general population.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Hipertensão/epidemiologia , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/etnologia , Humanos , Hipertensão/induzido quimicamente , Incidência , Masculino , Análise de Regressão , Fatores de Risco
9.
HIV Med ; 19(2): 102-117, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28984429

RESUMO

OBJECTIVES: There are currently few data on the long-term risk of cancer and death in individuals taking raltegravir (RAL). The aim of this analysis was to evaluate whether there is evidence for an association. METHODS: The EuroSIDA cohort was divided into three groups: those starting RAL-based combination antiretroviral therapy (cART) on or after 21 December 2007 (RAL); a historical cohort (HIST) of individuals adding a new antiretroviral (ARV) drug (not RAL) to their cART between 1 January 2005 and 20 December 2007, and a concurrent cohort (CONC) of individuals adding a new ARV drug (not RAL) to their cART on or after 21 December 2007. Baseline characteristics were compared using logistic regression. The incidences of newly diagnosed malignancies and death were compared using Poisson regression. RESULTS: The RAL cohort included 1470 individuals [with 4058 person-years of follow-up (PYFU)] compared with 3787 (4472 PYFU) and 4467 (10 691 PYFU) in the HIST and CONC cohorts, respectively. The prevalence of non-AIDS-related malignancies prior to baseline tended to be higher in the RAL cohort vs. the HIST cohort [adjusted odds ratio (aOR) 1.31; 95% confidence interval (CI) 0.95-1.80] and vs. the CONC cohort (aOR 1.89; 95% CI 1.37-2.61). In intention-to-treat (ITT) analysis (events: RAL, 50; HIST, 45; CONC, 127), the incidence of all new malignancies was 1.11 (95% CI 0.84-1.46) per 100 PYFU in the RAL cohort vs. 1.20 (95% CI 0.90-1.61) and 0.83 (95% CI 0.70-0.99) in the HIST and CONC cohorts, respectively. After adjustment, there was no evidence for a difference in the risk of malignancies [adjusted rate ratio (RR) 0.73; 95% CI 0.47-1.14 for RALvs. HIST; RR 0.95; 95% CI 0.65-1.39 for RALvs. CONC] or mortality (adjusted RR 0.87; 95% CI 0.53-1.43 for RALvs. HIST; RR 1.14; 95% CI 0.76-1.72 for RALvs. CONC). CONCLUSIONS: We found no evidence for an oncogenic risk or poorer survival associated with using RAL compared with control groups.


Assuntos
Antirretrovirais/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Neoplasias/epidemiologia , Neoplasias/mortalidade , Raltegravir Potássico/administração & dosagem , Adulto , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Análise de Sobrevida
10.
Am Nat ; 190(5): 601-616, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29053363

RESUMO

Widespread niche convergence suggests that species can be organized according to functional trait combinations to create a framework analogous to a periodic table. We compiled ecological data for lizards to examine patterns of global and regional niche diversification, and we used multivariate statistical approaches to develop the beginnings for a periodic table of niches. Data (50+ variables) for five major niche dimensions (habitat, diet, life history, metabolism, defense) were compiled for 134 species of lizards representing 24 of the 38 extant families. Principal coordinates analyses were performed on niche dimensional data sets, and species scores for the first three axes were used as input for a principal components analysis to ordinate species in continuous niche space and for a regression tree analysis to separate species into discrete niche categories. Three-dimensional models facilitate exploration of species positions in relation to major gradients within the niche hypervolume. The first gradient loads on body size, foraging mode, and clutch size. The second was influenced by metabolism and terrestrial versus arboreal microhabitat. The third was influenced by activity time, life history, and diet. Natural dichotomies are activity time, foraging mode, parity mode, and habitat. Regression tree analysis identified 103 cases of extreme niche conservatism within clades and 100 convergences between clades. Extending this approach to other taxa should lead to a wider understanding of niche evolution.


Assuntos
Evolução Biológica , Ecossistema , Características de História de Vida , Lagartos/fisiologia , Animais , Metabolismo Energético , Modelos Biológicos , Filogenia , Análise de Componente Principal
11.
Ecology ; 98(1): 21-31, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27984648

RESUMO

Despite growing interest in trait-based approaches to community assembly, little attention has been given to seasonal variation in trait distribution patterns. Mobile animals can rapidly mediate influences of environmental factors and species interactions through dispersal, suggesting that the relative importance of different assembly mechanisms can vary over short time scales. This study analyzes seasonal changes in functional trait distributions of tropical fishes in the Xingu River, a major tributary of the Amazon with large predictable temporal variation in hydrologic conditions and species density. Comparison of observed functional diversity revealed that species within wet-season assemblages were more functionally similar than those in dry-season assemblages. Further, species within wet-season assemblages were more similar than random expectations based on null model predictions. Higher functional richness within dry season communities is consistent with increased niche complementarity during the period when fish densities are highest and biotic interactions should be stronger; however, null model tests suggest that stochastic factors or a combination of assembly mechanisms influence dry-season assemblages. These results demonstrate that the relative influence of community assembly mechanisms can vary seasonally in response to changing abiotic conditions, and suggest that studies attempting to infer a single dominant mechanism from functional patterns may overlook important aspects of the assembly process. During the prolonged flood pulse of the wet season, expanded habitat and lower densities of aquatic organisms likely reduce the influence of competition and predation. This temporal shift in the influence of different assembly mechanisms, rather than any single mechanism, may play a large role in maintaining the structure and diversity of tropical rivers and perhaps other dynamic and biodiverse systems.


Assuntos
Biodiversidade , Ecossistema , Peixes , Animais , Rios , Estações do Ano
12.
HIV Med ; 17(8): 590-600, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26890156

RESUMO

OBJECTIVES: HIV-positive people have increased risk of infection-related malignancies (IRMs) and infection-unrelated malignancies (IURMs). The aim of the study was to determine the impact of aging on future IRM and IURM incidence. METHODS: People enrolled in EuroSIDA and followed from the latest of the first visit or 1 January 2001 until the last visit or death were included in the study. Poisson regression was used to investigate the impact of aging on the incidence of IRMs and IURMs, adjusting for demographic, clinical and laboratory confounders. Linear exponential smoothing models forecasted future incidence. RESULTS: A total of 15 648 people contributed 95 033 person-years of follow-up, of whom 610 developed 643 malignancies [IRMs: 388 (60%); IURMs: 255 (40%)]. After adjustment, a higher IRM incidence was associated with a lower CD4 count [adjusted incidence rate ratio (aIRR) CD4 count < 200 cells/µL: 3.77; 95% confidence interval (CI) 2.59, 5.51; compared with ≥ 500 cells/µL], independent of age, while a CD4 count < 200 cells/µL was associated with IURMs in people aged < 50 years only (aIRR: 2.51; 95% CI 1.40-4.54). Smoking was associated with IURMs (aIRR: 1.75; 95% CI 1.23, 2.49) compared with never smokers in people aged ≥ 50 years only, and not with IRMs. The incidences of both IURMs and IRMs increased with older age. It was projected that the incidence of IRMs would decrease by 29% over a 5-year period from 3.1 (95% CI 1.5-5.9) per 1000 person-years in 2011, whereas the IURM incidence would increase by 44% from 4.1 (95% CI 2.2-7.2) per 1000 person-years over the same period. CONCLUSIONS: Demographic and HIV-related risk factors for IURMs (aging and smoking) and IRMs (immunodeficiency and ongoing viral replication) differ markedly and the contribution from IURMs relative to IRMs will continue to increase as a result of aging of the HIV-infected population, high smoking and lung cancer prevalence and a low prevalence of untreated HIV infection. These findings suggest the need for targeted preventive measures and evaluation of the cost-benefit of screening for IURMs in HIV-infected populations.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/complicações , Envelhecimento , Infecções por HIV/complicações , Neoplasias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
13.
Glob Chang Biol ; 22(7): 2440-50, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26582547

RESUMO

Evidence for the theory of biotic resistance is equivocal, with experiments often finding a negative relationship between invasion success and native species richness, and large-scale comparative studies finding a positive relationship. Biotic resistance derives from local species interactions, yet global and regional studies often analyze data at coarse spatial grains. In addition, differences in competitive environments across regions may confound tests of biotic resistance based solely on native species richness of the invaded community. Using global and regional data sets for fishes in river and stream reaches, we ask two questions: (1) does a negative relationship exist between native and non-native species richness and (2) do non-native species originate from higher diversity systems. A negative relationship between native and non-native species richness in local assemblages was found at the global scale, while regional patterns revealed the opposite trend. At both spatial scales, however, nearly all non-native species originated from river basins with higher native species richness than the basin of the invaded community. Together, these findings imply that coevolved ecological interactions in species-rich systems inhibit establishment of generalist non-native species from less diverse communities. Consideration of both the ecological and evolutionary aspects of community assembly is critical to understanding invasion patterns. Distinct evolutionary histories in different regions strongly influence invasion of intact communities that are relatively unimpacted by human actions, and may explain the conflicting relationship between native and non-native species richness found at different spatial scales.


Assuntos
Biodiversidade , Peixes , Espécies Introduzidas , Animais , Evolução Biológica , Ecossistema , Água Doce , Humanos , Dinâmica Populacional
14.
Ecol Lett ; 18(8): 737-751, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26096695

RESUMO

Ecology is often said to lack general theories sufficiently predictive for applications. Here, we examine the concept of a periodic table of niches and feasibility of niche classification schemes from functional trait and performance data. Niche differences and their influence on ecological patterns and processes could be revealed effectively by first performing data reduction/ordination analyses separately on matrices of trait and performance data compiled according to logical associations with five basic niche 'dimensions', or aspects: habitat, life history, trophic, defence and metabolic. Resultant patterns then are integrated to produce interpretable niche gradients, ordinations and classifications. Degree of scheme periodicity would depend on degrees of niche conservatism and convergence causing species clustering across multiple niche dimensions. We analysed a sample data set containing trait and performance data to contrast two approaches for producing niche schemes: species ordination within niche gradient space, and niche categorisation according to trait-value thresholds. Creation of niche schemes useful for advancing ecological knowledge and its applications will depend on research that produces functional trait and performance datasets directly related to niche dimensions along with criteria for data standardisation and quality. As larger databases are compiled, opportunities will emerge to explore new methods for data reduction, ordination and classification.


Assuntos
Evolução Biológica , Ecologia/métodos , Ecossistema , Animais , Peixes , Modelos Biológicos
15.
HIV Med ; 16(9): 533-43, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25988795

RESUMO

OBJECTIVES: The long-term side effects of stavudine (d4T) led to recommendations in 2009 to phase out use of this drug. We aimed to describe temporal patterns of d4T use across Europe. METHODS: Patients taking combination antiretroviral therapy (cART) in EuroSIDA with follow-up after 1 January 2006 were included in the study. cART was defined as d4T-containing [d4T plus at least two other antiretrovirals (ARVs) from any class] or non-d4T-containing (at least three ARVs from any class, excluding d4T). Poisson regression was used to describe temporal changes in the prevalence of d4T use and factors associated with initiating d4T. RESULTS: A total of 5850 patients receiving cART on 1 January 2006 were included in the current analysis, rising to 7768 patients on January 1 2013. During this time, the prevalence of d4T use fell from 11.2% to 0.7%, with an overall decline of 19% per 6 months [95% confidence interval (CI) 19-20%]. d4T use declined fastest in Northern Europe [26% (95% CI 23-29%) per 6 months], and slowest in Eastern Europe [17% (95% CI 16-19%) per 6 months]. In multivariable Poisson regression models, new d4T initiations decreased by 14% per 6 months [adjusted incidence rate ratio (aIRR) 0.86; 95% CI 0.80-0.91]. Factors associated with initiating d4T were residence in Eastern Europe (aIRR 4.31; 95% CI 2.17-9.98) versus other European regions and HIV RNA > 400 copies/mL (aIRR 3.11; 95% CI 1.60-6.02) versus HIV RNA < 400 copies/mL. CONCLUSIONS: d4T use has declined sharply since 2006 to low levels in most regions; however, a low but persistent level of d4T use remains in Eastern Europe, where new d4T initiations post 2006 are also more common. The reasons for the regional differences may be multifactorial, but it is important to ensure that all clinicians treating HIV-positive patients are aware of the potential harmful effects associated with d4T.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Estavudina/uso terapêutico , Adulto , Fármacos Anti-HIV/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Europa (Continente) , Feminino , Seguimentos , HIV-1/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/análise , RNA Viral/efeitos dos fármacos , Análise de Regressão , Estavudina/efeitos adversos
16.
HIV Med ; 16(9): 544-52, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25959854

RESUMO

OBJECTIVES: The aim of the study was to investigate the organization and delivery of HIV and tuberculosis (TB) health care and to analyse potential differences between treatment centres in Eastern (EE) and Western Europe (WE). METHODS: Thirty-eight European HIV and TB treatment centres participating in the TB:HIV study within EuroCoord completed a survey on health care management for coinfected patients in 2013 (EE: 17 respondents; WE:21; 76% of all TB:HIV centres). Descriptive statistics were obtained for regional comparisons. The reported data on health care strategies were compared with actual clinical practice at patient level via data derived from the TB:HIV study. RESULTS: Respondent centres in EE comprised: Belarus (n = 3), Estonia (1), Georgia (1), Latvia (1), Lithuania (1), Poland (4), Romania (1), the Russian Federation (4) and Ukraine (1); those in WE comprised: Belgium (1), Denmark (1), France (1), Italy (7), Spain (2), Switzerland (1) and UK (8). Compared with WE, treatment of HIV and TB in EE are less often located at the same site (47% in EE versus 100% in WE; P < 0.001) and less often provided by the same doctors (41% versus 90%, respectively; P = 0.002), whereas regular screening of HIV-infected patients for TB (80% versus 40%, respectively; P = 0.037) and directly observed treatment (88% versus 20%, respectively; P < 0.001) were more common in EE. The reported availability of rifabutin and second- and third-line anti-TB drugs was lower, and opioid substitution therapy (OST) was available at fewer centres in EE compared with WE (53% versus 100%, respectively; P < 0.001). CONCLUSIONS: Major differences exist between EE and WE in relation to the organization and delivery of health care for HIV/TB-coinfected patients and the availability of anti-TB drugs and OST. Significant discrepancies between reported and actual clinical practices were found in EE.


Assuntos
Antituberculosos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Coinfecção/diagnóstico , Coinfecção/tratamento farmacológico , Estudos Transversais , Europa (Continente) , Europa Oriental , Infecções por HIV/microbiologia , Inquéritos Epidemiológicos , Humanos , Tratamento de Substituição de Opiáceos/métodos , Rifabutina/uso terapêutico
17.
Environ Manage ; 56(4): 835-46, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26092052

RESUMO

Recent literature reviews of bioassessment methods raise questions about use of least-impacted reference sites to characterize natural conditions that no longer exist within contemporary landscapes. We explore an alternate approach for bioassessment that uses species site occupancy data from museum archives as input for species distribution models (SDMs) stacked to predict species assemblages of freshwater fishes in Texas. When data for estimating reference conditions are lacking, deviation between richness of contemporary versus modeled species assemblages could provide a means to infer relative biological integrity at appropriate spatial scales. We constructed SDMs for 100 freshwater fish species to compare predicted species assemblages to data on contemporary assemblages acquired by four independent surveys that sampled 269 sites. We then compared site-specific observed/predicted ratios of the number of species at sites to scores from a multimetric index of biotic integrity (IBI). Predicted numbers of species were moderately to strongly correlated with the numbers observed by the four surveys. We found significant, though weak, relationships between observed/predicted ratios and IBI scores. SDM-based assessments identified patterns of local assemblage change that were congruent with IBI inferences; however, modeling artifacts that likely contributed to over-prediction of species presence may restrict the stand-alone use of SDM-derived patterns for bioassessment and therefore warrant examination. Our results suggest that when extensive standardized survey data that include reference sites are lacking, as is commonly the case, SDMs derived from generally much more readily available species site occupancy data could be used to provide a complementary tool for bioassessment.


Assuntos
Monitoramento Ambiental/métodos , Peixes/fisiologia , Água Doce , Modelos Teóricos , Animais , Dinâmica Populacional , Texas
18.
HIV Med ; 15(3): 144-52, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24118916

RESUMO

OBJECTIVES: The aim of this study was to determine whether the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)- or Cockcroft-Gault (CG)-based estimated glomerular filtration rates (eGFRs) performs better in the cohort setting for predicting moderate/advanced chronic kidney disease (CKD) or end-stage renal disease (ESRD). METHODS: A total of 9521 persons in the EuroSIDA study contributed 133 873 eGFRs. Poisson regression was used to model the incidence of moderate and advanced CKD (confirmed eGFR < 60 and < 30 mL/min/1.73 m(2) , respectively) or ESRD (fatal/nonfatal) using CG and CKD-EPI eGFRs. RESULTS: Of 133 873 eGFR values, the ratio of CG to CKD-EPI was ≥ 1.1 in 22 092 (16.5%) and the difference between them (CG minus CKD-EPI) was ≥ 10 mL/min/1.73 m(2) in 20 867 (15.6%). Differences between CKD-EPI and CG were much greater when CG was not standardized for body surface area (BSA). A total of 403 persons developed moderate CKD using CG [incidence 8.9/1000 person-years of follow-up (PYFU); 95% confidence interval (CI) 8.0-9.8] and 364 using CKD-EPI (incidence 7.3/1000 PYFU; 95% CI 6.5-8.0). CG-derived eGFRs were equal to CKD-EPI-derived eGFRs at predicting ESRD (n = 36) and death (n = 565), as measured by the Akaike information criterion. CG-based moderate and advanced CKDs were associated with ESRD [adjusted incidence rate ratio (aIRR) 7.17; 95% CI 2.65-19.36 and aIRR 23.46; 95% CI 8.54-64.48, respectively], as were CKD-EPI-based moderate and advanced CKDs (aIRR 12.41; 95% CI 4.74-32.51 and aIRR 12.44; 95% CI 4.83-32.03, respectively). CONCLUSIONS: Differences between eGFRs using CG adjusted for BSA or CKD-EPI were modest. In the absence of a gold standard, the two formulae predicted clinical outcomes with equal precision and can be used to estimate GFR in HIV-positive persons.


Assuntos
Taxa de Filtração Glomerular , Infecções por HIV/fisiopatologia , Insuficiência Renal Crônica/diagnóstico , Progressão da Doença , Europa (Continente)/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Masculino , Modelos Estatísticos , Distribuição de Poisson , Estudos Prospectivos , Insuficiência Renal Crônica/epidemiologia
19.
HIV Med ; 15(10): 595-603, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24840675

RESUMO

OBJECTIVES: The aim of the study was to statistically model the relative increased risk of cardiovascular disease (CVD) per year older in Data collection on Adverse events of anti-HIV Drugs (D:A:D) and to compare this with the relative increased risk of CVD per year older in general population risk equations. METHODS: We analysed three endpoints: myocardial infarction (MI), coronary heart disease (CHD: MI or invasive coronary procedure) and CVD (CHD or stroke). We fitted a number of parametric age effects, adjusting for known risk factors and antiretroviral therapy (ART) use. The best-fitting age effect was determined using the Akaike information criterion. We compared the ageing effect from D:A:D with that from the general population risk equations: the Framingham Heart Study, CUORE and ASSIGN risk scores. RESULTS: A total of 24 323 men were included in analyses. Crude MI, CHD and CVD event rates per 1000 person-years increased from 2.29, 3.11 and 3.65 in those aged 40-45 years to 6.53, 11.91 and 15.89 in those aged 60-65 years, respectively. The best-fitting models included inverse age for MI and age + age(2) for CHD and CVD. In D:A:D there was a slowly accelerating increased risk of CHD and CVD per year older, which appeared to be only modest yet was consistently raised compared with the risk in the general population. The relative risk of MI with age was not different between D:A:D and the general population. CONCLUSIONS: We found only limited evidence of accelerating increased risk of CVD with age in D:A:D compared with the general population. The absolute risk of CVD associated with HIV infection remains uncertain.


Assuntos
Doença das Coronárias/etiologia , Infecções por HIV/complicações , Infarto do Miocárdio/etiologia , Acidente Vascular Cerebral/etiologia , Adulto , Fatores Etários , Idoso , Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Fatores de Risco
20.
Ecology ; 95(1): 210-24, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24649660

RESUMO

In response to temporal changes in the quality and availability of food resources, consumers should adjust their foraging behavior in a manner that maximizes energy and nutrient intake and, when resources are limiting, minimizes dietary overlap with other consumers. Floodplains of the Amazon and its lowland tributaries are characterized by strong, yet predictable, hydrological seasonality, seasonal availability of fruits, seeds, and other food resources of terrestrial origin, and diverse assemblages of frugivorous fishes, including morphologically similar species of several characiform families. Here, we investigated how diets of frugivorous fishes in the Amazon change in response to fluctuations in food availability, and how this influences patterns of interspecific dietary overlap. We tested predictions from classical theories of foraging and resource competition by estimating changes in diet breadth and overlap across seasons. We monitored fruiting phenology to assess food availability, and surveyed local fish populations during three hydrological seasons in an oligotrophic river and an adjacent oxbow lake in the Colombian Amazon. We analyzed stomach contents and stable isotope data to evaluate temporal and interspecific relationships for dietary composition, breadth, and overlap. Diets of six species of characiform fishes representing three genera changed according to seasonal fluctuations in food availability, and patterns of diet breadth and interspecific overlap during the peak flood pulse were consistent with predictions of optimal foraging theory. During times of high fruit abundance, fishes consumed items to which their functional morphological traits seemed best adapted, potentially enhancing net energy and nutritional gains. As the annual flood pulse subsided and availability of forest food resources in aquatic habitats changed, there was not a consistent pattern of diet breadth expansion or compression. Nonetheless, shifts in both diet composition and stable isotope ratios of consumer tissues during this period resulted in trophic niche segregation in a pattern consistent with competition theory.


Assuntos
Comportamento Alimentar/fisiologia , Peixes/fisiologia , Frutas , Rios , Árvores , Animais , Ecossistema , Estações do Ano , Fatores de Tempo
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