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1.
Microbiome ; 10(1): 113, 2022 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902906

RESUMEN

BACKGROUND: The importance of symbiosis has long been recognized on coral reefs, where the photosynthetic dinoflagellates of corals (Symbiodiniaceae) are the primary symbiont. Numerous studies have now shown that a diverse assemblage of prokaryotes also make-up part of the microbiome of corals. A subset of these prokaryotes is capable of fixing nitrogen, known as diazotrophs, and is also present in the microbiome of scleractinian corals where they have been shown to supplement the holobiont nitrogen budget. Here, an analysis of the microbiomes of 16 coral species collected from Australia, Curaçao, and Hawai'i using three different marker genes (16S rRNA, nifH, and ITS2) is presented. These data were used to examine the effects of biogeography, coral traits, and ecological life history characteristics on the composition and diversity of the microbiome in corals and their diazotrophic communities. RESULTS: The prokaryotic microbiome community composition (i.e., beta diversity) based on the 16S rRNA gene varied between sites and ecological life history characteristics, but coral morphology was the most significant factor affecting the microbiome of the corals studied. For 15 of the corals studied, only two species Pocillopora acuta and Seriotopora hystrix, both brooders, showed a weak relationship between the 16S rRNA gene community structure and the diazotrophic members of the microbiome using the nifH marker gene, suggesting that many corals support a microbiome with diazotrophic capabilities. The order Rhizobiales, a taxon that contains primarily diazotrophs, are common members of the coral microbiome and were eight times greater in relative abundances in Hawai'i compared to corals from either Curacao or Australia. However, for the diazotrophic component of the coral microbiome, only host species significantly influenced the composition and diversity of the community. CONCLUSIONS: The roles and interactions between members of the coral holobiont are still not well understood, especially critical functions provided by the coral microbiome (e.g., nitrogen fixation), and the variation of these functions across species. The findings presented here show the significant effect of morphology, a coral "super trait," on the overall community structure of the microbiome in corals and that there is a strong association of the diazotrophic community within the microbiome of corals. However, the underlying coral traits linking the effects of host species on diazotrophic communities remain unknown. Video Abstract.


Asunto(s)
Antozoos , Dinoflagelados , Microbiota , Animales , Antozoos/genética , Arrecifes de Coral , Dinoflagelados/genética , Microbiota/genética , Nitrógeno , ARN Ribosómico 16S/genética , Simbiosis
2.
J Phycol ; 56(3): 592-607, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32159226

RESUMEN

Distributed in tropical and warm-temperate waters worldwide, Lobophora species are found across the Greater Caribbean (i.e., Caribbean sensu stricto, Gulf of Mexico, Florida, the Bahamas, and Bermuda). We presently discuss the diversity, ecology, biogeography, and evolution of the Greater Caribbean Lobophora species based on previous studies and an extensive number of samples collected across the eastern, southern, and to a lesser extent western Caribbean. A total of 18 Lobophora species are now documented from the Greater Caribbean, of which five are newly described (L. agardhii sp. nov., L. dickiei sp. nov., L. lamourouxii sp. nov., L. richardii sp. nov., and L. setchellii sp. nov.). Within the Greater Caribbean, the eastern Caribbean and the Central Province are the most diverse ecoregion and province (16 spp.), respectively. Observed distribution patterns indicate that Lobophora species from the Greater Caribbean have climate affinities (i.e., warm-temperate vs. tropical affinities). In total, 11 Lobophora species exclusively occur in the Greater Caribbean; six are present in the western Atlantic; two in the Indo-Pacific; and one in the eastern Pacific. Biogeographic analyses support that no speciation occurred across the Isthmus of Panama, and that the Greater Caribbean acted as a recipient region for species from the Indo-Pacific and as a region of diversification as well as a donor region to the North-eastern Atlantic. The Greater Caribbean is not an evolutionary dead end for Lobophora, but instead generates and exports diversity. Present results illustrate how sampling based on DNA identification is reshaping biogeographic patterns, as we know them.


Asunto(s)
Phaeophyceae , Región del Caribe , Ecología , Florida , Golfo de México , Filogenia
3.
Nat Microbiol ; 4(12): 2090-2100, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31548681

RESUMEN

Corals and the reef ecosystems that they support are in global decline due to increasing anthropogenic pressures such as climate change1. However, effective reef conservation strategies are hampered by a limited mechanistic understanding of coral biology and the functional roles of the diverse microbial communities that underpin coral health2,3. Here, we present an integrated genomic characterization of the coral species Porites lutea and its microbial partners. High-quality genomes were recovered from P. lutea, as well as a metagenome-assembled Cladocopium C15 (the dinoflagellate symbiont) and 52 bacterial and archaeal populations. Comparative genomic analysis revealed that many of the bacterial and archaeal genomes encode motifs that may be involved in maintaining association with the coral host and in supplying fixed carbon, B-vitamins and amino acids to their eukaryotic partners. Furthermore, mechanisms for ammonia, urea, nitrate, dimethylsulfoniopropionate and taurine transformation were identified that interlink members of the holobiont and may be important for nutrient acquisition and retention in oligotrophic waters. Our findings demonstrate the critical and diverse roles that microorganisms play within the coral holobiont and underscore the need to consider all of the components of the holobiont if we are to effectively inform reef conservation strategies.


Asunto(s)
Antozoos/microbiología , Archaea/genética , Bacterias/genética , Genoma , Simbiosis , Animales , Antozoos/metabolismo , Arrecifes de Coral , Dinoflagelados/genética , Metagenómica , Microbiota
4.
Front Microbiol ; 9: 2621, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30443242

RESUMEN

Ocean acidification (OA) as a result of increased anthropogenic CO2 input into the atmosphere carries consequences for all ocean life. Low pH can cause a shift in coral-associated microbial communities of pCO2-sensitive corals, however, it remains unknown whether the microbial community is also influenced in corals known to be more tolerant to high pCO2/low pH. This study profiles the bacterial communities associated with the tissues of the pCO2-tolerant coral, massive Porites spp., from two natural CO2 seep sites in Papua New Guinea. Amplicon sequencing of the hypervariable V3-V4 regions of the 16S rRNA gene revealed that microbial communities remained stable across CO2 seep sites (pH = 7.44-7.85) and adjacent control sites (ambient pH = 8.0-8.1). Microbial communities were more significantly influenced by reef location than pH, with the relative abundance of dominant microbial taxa differing between reefs. These results directly contrast with previous findings that increased CO2 has a strong effect on structuring microbial communities. The stable structure of microbial communities associated with the tissues of massive Porites spp. under high pCO2/low pH conditions confirms a high degree of tolerance by the whole Porites holobiont to OA, and suggest that pH tolerant corals such as Porites may dominate reef assemblages in an increasingly acidic ocean.

5.
FEMS Microbiol Ecol ; 94(4)2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29471328

RESUMEN

Symbiotic associations with subcuticular bacteria (SCB) have been identified and studied in many echinoderms, including the SCB of the brooding brittle star, Amphipholis squamata. Previous studies on the SCB of A. squamata placed the isolated bacterium, designated as AS1, in the genus Vibrio (Gammaproteobacteria), but subsequent studies suggested that the SCB of echinoderms belong to the Alphaproteobacteria. This study examines the taxonomic composition of SCB associated with A. squamata from the Northwest Atlantic using the 16S rRNA gene and next generation sequencing. Results show the presence of a single dominant bacterial type, within the Roseobacter clade, family Rhodobacteraceae, which composes 70%-80% of the A. squamata microbiome. These Rhodobacteraceae sequences were identified as members of the genus Octadecabacter. Additionally, the original isolate, AS1, from the brittle star A. squamata also belongs in the genus Octadecabacter based on Sanger sequencing of cloned 16S rRNA gene sequences. By comparison, adjacent seawater and sediment porewater communities were significantly more diverse, hosting bacteria in the phyla Proteobacteria, Bacteroidetes, Cyanobacteria, Verrucomicrobia and Actinobacteria. Thus, a distinct SCB community is present in A. squamata that is dominated by a member of the genus Octadecabacter and is identical to the original isolate, AS1, from this brittle star.


Asunto(s)
ADN Bacteriano/genética , Sedimentos Geológicos/microbiología , Roseobacter , Agua de Mar/microbiología , Estrellas de Mar/microbiología , Animales , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Cianobacterias/genética , Cianobacterias/aislamiento & purificación , Filogenia , Proteobacteria/genética , Proteobacteria/aislamiento & purificación , ARN Ribosómico 16S/genética , Roseobacter/clasificación , Roseobacter/genética , Roseobacter/aislamiento & purificación , Análisis de Secuencia de ADN , Simbiosis
6.
ISME J ; 12(3): 813-824, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29222444

RESUMEN

Diazotrophs, both Bacteria and Archaea, capable of fixing nitrogen (N2), are present in the tissues and mucous, of corals and can supplement the coral holobiont nitrogen budget with fixed nitrogen (N) in the form of ammonia (NH3). Stylophora pistillata from Heron Island on the Great Barrier Reef collected at 5 and 15 m, and experimentally manipulated in the laboratory, showed that the rates of net photosynthesis, steady state quantum yields of photosystem II (PSII) fluorescence (∆Fv/Fm') and calcification varied based on irradiance as expected. Rates of N2 fixation were, however, invariant across treatments while the amount of fixed N contributing to Symbiodinium spp. N demand is irradiance dependent. Additionally, both the Symbiodinium and diazotrophic communities are significantly different based on depth, and novel Cluster V nifH gene phylotypes, which are not known to fix nitrogen, were recovered. A functional analysis using PICRUSt also showed that shallow corals were enriched in genes involved in nitrogen metabolism, and N2 fixation specifically. Corals have evolved a number of strategies to derive nitrogen from organic (e.g., heterotrophic feeding) and inorganic sources (e.g., N2 fixation) to maintain critical pathways such as protein synthesis to succeed ecologically in nitrogen-limited habitats.


Asunto(s)
Antozoos/microbiología , Arrecifes de Coral , Dinoflagelados/metabolismo , Fijación del Nitrógeno/fisiología , Nitrógeno/metabolismo , Fotosíntesis/fisiología , Animales , Bacterias/genética , Procesos Heterotróficos , Metagenoma , Fijación del Nitrógeno/efectos de la radiación , Fotosíntesis/efectos de la radiación , Complejo de Proteína del Fotosistema II/metabolismo , Análisis de Secuencia de ADN
7.
Sci Rep ; 7(1): 16039, 2017 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-29167578

RESUMEN

Montastraea cavernosa is a common coral in the Caribbean basin found in several color morphs. To investigate the causes for brown and orange morphs we undertook a genomics approach on corals collected at the same time and depth in the Bahamas. The coral holobiont includes the host, symbiotic dinoflagellates (Symbiodinium spp.), and a diverse microbiome. While the coral host showed significant genetic differentiation between color morphs both the composition of the Symbiodinium spp. communities and the prokaryotic communities did not. Both targeted and global gene expression differences in the transcriptome of the host show no difference in fluorescent proteins while the metatranscriptome of the microbiome shows that pigments such as phycoerythrin and orange carotenoid protein of cyanobacterial origin are significantly greater in orange morphs, which is also consistent with the significantly greater number of cyanobacteria quantified by 16S rRNA reads and flow cytometry. The microbiome of orange color morphs expressed significantly more nitrogenase (nifH) transcripts consistent with their known ability to fix nitrogen. Both coral and Symbiodinium spp. transcriptomes from orange morphs had significantly increased expression of genes related to immune response and apoptosis, which may potentially be involved in maintaining and regulating the unique symbiont population in orange morphs.


Asunto(s)
Antozoos/genética , Genómica/métodos , Animales , Dinoflagelados/genética , ARN Ribosómico 16S/genética
8.
Mol Ecol ; 26(19): 5344-5357, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28748644

RESUMEN

The health and functioning of reef-building corals is dependent on a balanced association with prokaryotic and eukaryotic microbes. The coral skeleton harbours numerous endolithic microbes, but their diversity, ecological roles and responses to environmental stress, including ocean acidification (OA), are not well characterized. This study tests whether pH affects the diversity and structure of prokaryotic and eukaryotic algal communities associated with skeletons of Porites spp. using targeted amplicon (16S rRNA gene, UPA and tufA) sequencing. We found that the composition of endolithic communities in the massive coral Porites spp. inhabiting a naturally high pCO2 reef (avg. pCO2 811 µatm) is not significantly different from corals inhabiting reference sites (avg. pCO2 357 µatm), suggesting that these microbiomes are less disturbed by OA than previously thought. Possible explanations may be that the endolithic microhabitat is highly homeostatic or that the endolithic micro-organisms are well adapted to a wide pH range. Some of the microbial taxa identified include nitrogen-fixing bacteria (Rhizobiales and cyanobacteria), algicidal bacteria in the phylum Bacteroidetes, symbiotic bacteria in the family Endozoicomoniaceae, and endolithic green algae, considered the major microbial agent of reef bioerosion. Additionally, we test whether host species has an effect on the endolithic community structure. We show that the endolithic community of massive Porites spp. is substantially different and more diverse than that found in skeletons of the branching species Seriatopora hystrix and Pocillopora damicornis. This study reveals highly diverse and structured microbial communities in Porites spp. skeletons that are possibly resilient to OA.


Asunto(s)
Antozoos/microbiología , Dióxido de Carbono/química , Microbiota , Animales , Chlorophyta/clasificación , Arrecifes de Coral , Cianobacterias/clasificación , Papúa Nueva Guinea , ARN Ribosómico 16S/genética , Agua de Mar/química
9.
Appl Environ Microbiol ; 83(1)2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27795310

RESUMEN

Pervasive environmental stressors on coral reefs are attributed with shifting the competitive balance in favor of alternative dominants, such as macroalgae. Previous studies have demonstrated that macroalgae compete with corals via a number of mechanisms, including the production of potent primary and secondary metabolites that can influence coral-associated microbial communities. The present study investigates the effects of the Pacific brown macroalga Lobophora sp. (due to the shifting nature of the Lobophora species complex, it will be referred to here as Lobophora sp.) on coral bacterial isolates, coral larvae, and the microbiome associated with the coral Porites cylindrica. Crude aqueous and organic macroalgal extracts were found to inhibit the growth of coral-associated bacteria. Extracts and fractions were also shown to inhibit coral larval settlement and cause mortality at concentrations lower (<0.3 mg · ml-1) than calculated natural concentrations (4.4 mg · ml-1). Microbial communities associated with coral tissues exposed to aqueous (e.g., hydrophilic) crude extracts demonstrated a significant shift to Vibrio dominance and a loss of sequences related to the putative coral bacterial symbiont, Endozoicomonas sp., based on 16S rRNA amplicon sequencing. This study contributes to growing evidence that macroalgal allelochemicals, dissolved organic material, and native macroalgal microbial assemblages all play a role in shifting the microbial equilibrium of the coral holobiont away from a beneficial state, contributing to a decline in coral fitness and a shift in ecosystem structure. IMPORTANCE: Diverse microbial communities associate with coral tissues and mucus, providing important protective and nutritional services, but once disturbed, the microbial equilibrium may shift from a beneficial state to one that is detrimental or pathogenic. Macroalgae (e.g., seaweeds) can physically and chemically interact with corals, causing abrasion, bleaching, and overall stress. This study contributes to a growing body of evidence suggesting that macroalgae play a critical role in shifting the coral holobiont equilibrium, which may promote the invasion of opportunistic pathogens and cause coral mortality, facilitating additional macroalgal growth and invasion in the reef. Thus, macroalgae not only contribute to a decline in coral fitness but also influence coral reef ecosystem structure.


Asunto(s)
Antozoos/microbiología , Microbiota/efectos de los fármacos , Phaeophyceae/química , Feromonas/farmacología , Algas Marinas/fisiología , Vibrio/aislamiento & purificación , Animales , Antozoos/efectos de los fármacos , Archaea/efectos de los fármacos , Archaea/genética , Archaea/crecimiento & desarrollo , Archaea/aislamiento & purificación , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/crecimiento & desarrollo , Bacterias/patogenicidad , Arrecifes de Coral , Ecosistema , Larva/efectos de los fármacos , Metagenómica , Consorcios Microbianos/efectos de los fármacos , Consorcios Microbianos/genética , Microbiota/genética , Phaeophyceae/fisiología , Feromonas/biosíntesis , Feromonas/química , Dinámica Poblacional , ARN Ribosómico 16S , Algas Marinas/química , Algas Marinas/crecimiento & desarrollo , Vibrio/patogenicidad , Vibrio/fisiología
10.
Annu Rev Microbiol ; 70: 317-40, 2016 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-27482741

RESUMEN

Corals are fundamental ecosystem engineers, creating large, intricate reefs that support diverse and abundant marine life. At the core of a healthy coral animal is a dynamic relationship with microorganisms, including a mutually beneficial symbiosis with photosynthetic dinoflagellates (Symbiodinium spp.) and enduring partnerships with an array of bacterial, archaeal, fungal, protistan, and viral associates, collectively termed the coral holobiont. The combined genomes of this coral holobiont form a coral hologenome, and genomic interactions within the hologenome ultimately define the coral phenotype. Here we integrate contemporary scientific knowledge regarding the ecological, host-specific, and environmental forces shaping the diversity, specificity, and distribution of microbial symbionts within the coral holobiont, explore physiological pathways that contribute to holobiont fitness, and describe potential mechanisms for holobiont homeostasis. Understanding the role of the microbiome in coral resilience, acclimation, and environmental adaptation is a new frontier in reef science that will require large-scale collaborative research efforts.


Asunto(s)
Antozoos/microbiología , Antozoos/fisiología , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Microbiota , Animales , Antozoos/genética , Bacterias/clasificación , Bacterias/genética , Bacterias/crecimiento & desarrollo , Arrecifes de Coral , Ecosistema , Hongos/clasificación , Hongos/genética , Hongos/crecimiento & desarrollo
11.
Environ Microbiol ; 18(6): 2025-38, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26769079

RESUMEN

The giant barrel sponge, Xestospongia muta, is a high microbial abundance sponge found on Caribbean coral reefs along shallow to mesophotic depth gradients where multiple abiotic factors change with depth. Sponges were collected along a depth gradient at Little Cayman (LC) and Lee Stocking Island (LSI), and the microbiome of these samples was analysed using 16S rRNA amplicon sequencing. Statistically significant shifts in community structure and dissimilarity (∼ 40%) were detected from 10 to 90 m in LC sponges, but a similar shift was not identified in sponges from 10 to 60 m at LSI (only 17% dissimilar). Additionally, inorganic nutrient levels steadily increased with depth at LSI but not at LC. Based on bulk stable isotopic variability, sponges collected from LC were generally more enriched in (15) N and less enriched in (13) C as depth increased, suggesting a transition from dependency on photoautotrophy to heterotrophy as depth increased. Patterns of stable isotopic enrichment were largely invariant at LSI, which is also reflected in the more stable microbial community along the depth gradient. It appears that environmental factors that change with depth may contribute to differences in X. muta microbial assemblages, demonstrating the importance of contemporaneous environmental sampling in studies of the microbiome of sponges.


Asunto(s)
Xestospongia/microbiología , Animales , Región del Caribe , Arrecifes de Coral , Microbiota/genética , ARN Ribosómico 16S/genética , Agua de Mar/microbiología
12.
AIDS Behav ; 20(7): 1514-26, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-25963772

RESUMEN

We investigated message comprehension and message framing preferences for communicating about PrEP efficacy with US MSM. We conducted eight focus groups (n = 38) and n = 56 individual interviews with MSM in Providence, RI. Facilitators probed comprehension, credibility, and acceptability of efficacy messages, including percentages, non-numerical paraphrases, efficacy ranges versus point estimates, and success- versus failure-framed messages. Our findings indicated a range of comprehension and operational understandings of efficacy messages. Participants tended to prefer percentage-based and success-framed messages, although preferences varied for communicating about efficacy using a single percentage versus a range. Participants reported uncertainty about how to interpret numerical estimates, and many questioned whether trial results would predict personal effectiveness. These results suggest that providers and researchers implementing PrEP may face challenges in communicating with users about efficacy. Efforts to educate MSM about PrEP should incorporate percentage-based information, and message framing decisions may influence message credibility and overall PrEP acceptability.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Profilaxis Pre-Exposición , Adulto , Comprensión , Grupos Focales , Alfabetización en Salud , Humanos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Investigación Cualitativa , Adulto Joven
13.
Proc Annu Hawaii Int Conf Syst Sci ; 2015: 3247-3255, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26640419

RESUMEN

Mobile psychological interventions are of growing interest, particularly for populations with little access to traditional mental health services. Optimum structural components of these interventions are unknown. In this study, twenty-one adolescents (age 13-17) with past two week depressive symptoms were recruited from the emergency department to participate in a semi-structured interview, to inform development of a text-message-based depression prevention intervention. Teens expressed conflict about intervention structure. Although trust and reliability were essential to sustain engagement, teens disagreed about how to best maintain reliability; whether the program should be "pushed" or "pulled"; and what the ideal degree of human interaction would be. These findings highlight the challenges in automating psychological interventions that are normally delivered face-to-face. Data indicate a broad desire for developing tailoring methods for system design (duration, frequency, and level of interactivity). The paper closes with thoughts about potential solutions to these structural issues for mobile psychological interventions.

14.
Addict Disord Their Treat ; 14(2): 95-104, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26167133

RESUMEN

BACKGROUND: Drug use and partner abuse often coexist among women presenting to the emergency department (ED). Technology offers one solution to the limited time and expertise available to address these problems. AIMS: The aims of this study were to explore womens' attitudes about use of computers for screening and intervening in drug use and partner abuse. METHODS: Seventeen adult women with recent histories of partner abuse and drug use were recruited from an urban ED to participate in one-on-one semi-structured interviews. A coding classification scheme was developed and applied to the transcripts by two independent coders. The research team collaboratively decided upon a thematic framework and selected illustrative quotes. RESULTS: Most participants used computers and/or mobile phones frequently and reported high self-efficacy with them. Women described emotional difficulty and shame around partner abuse experiences and drug use; however, they felt that reporting drug use and partner abuse was easier and safer through a computer than face-to-face with a person, and that advice from a computer about drug use or partner abuse was acceptable and accessible. Some had very positive experiences completing screening assessments. However, participants were skeptical of a computer's ability to give empathy, emotional support or meaningful feedback. The ED was felt to be an appropriate venue for such programs, as long as they were private and did not supersede clinical care. CONCLUSIONS: Women with partner abuse and drug use histories were receptive to computerized screening and advice, while still expressing a need for the empathy and compassion of a human interaction within an intervention.

15.
Nicotine Tob Res ; 17(8): 975-82, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26180222

RESUMEN

INTRODUCTION: Tobacco use has emerged as a leading killer among persons living with HIV, with effective approaches to tobacco treatment still unknown. HIV infection is nearly 3 times as prevalent in Latinos than in non-Latino Whites. This study reports the results of a randomized trial comparing a tailored intervention to brief counseling for smoking cessation among Latino smokers living with HIV (LSLWH). METHODS: LSLWH (N = 302; 36% female, 10% employed full-time, 49% born in United States) were randomized to 4 in-person sessions of a tailored intervention (Aurora) or 2 in-person sessions of brief advice (enhanced standard care [ESC]). Both groups received 8 weeks of nicotine replacement therapy (NRT) patch. Biochemically validated 6- and 12-month 7-day point-prevalence abstinence (PPA) rates were compared, along with secondary outcomes (e.g., reduction to light smoking, NRT adherence). RESULTS: Seven-day PPA rates reached 8% versus 11% at 6 months and 6% versus 7% at 12 months, for Aurora and ESC, respectively, with no between-group differences (p values > .40). Significant changes from baseline to 6 and 12 months among intervention targets were noted (percentage reduction in heavy smoking and dependence; increases in knowledge and self-efficacy). Baseline smoking frequency, older age, and higher intensity of patch use during the trial emerged as significant predictors of abstinence at 6 months. CONCLUSIONS: There was no evidence that the tailored intervention improved cessation rates. Interventions that encourage use of, and adherence to, empirically validated cessation aids require further development to reduce tobacco-related death and disease in this vulnerable population.


Asunto(s)
Consejo/métodos , Infecciones por VIH , Hispánicos o Latinos , Cese del Hábito de Fumar/métodos , Dispositivos para Dejar de Fumar Tabaco , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cese del Hábito de Fumar/etnología , Encuestas y Cuestionarios , Resultado del Tratamiento , Estados Unidos
16.
J Urban Health ; 92(4): 667-86, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25930083

RESUMEN

Access to biomedical HIV prevention technologies such as pre-exposure prophylaxis (PrEP) requires individuals to disclose risk behavior to clinicians, but experiences of discrimination and medical mistrust may limit disclosure among male sex workers and other MSM. We explored experiences of perceived discrimination, medical mistrust, and behavior disclosure among male sex workers compared to other men who have sex with men (MSM). We conducted 56 interviews with MSM and compared findings about medical mistrust, discrimination, and disclosure for 31 men who engaged in sex work vs. 25 men who did not. MSM who engaged in sex work reported more medical mistrust and healthcare discrimination due to issues beyond MSM behavior/identity (e.g., homelessness, substance use, poverty). MSM who did not report sex work described disclosing sex with men to clinicians more often. Both subgroups reported low PrEP awareness, but willingness to disclose behavior to obtain PrEP. Medical mistrust and perceived discrimination create barriers for sexual behavior disclosure to clinicians, potentially impeding access to PrEP and other forms of biomedical HIV prevention. These barriers may be higher among male sex workers compared to other MSM, given overlapping stigmas including sex work, substance use, homelessness, and poverty. An intersectionality framework for understanding multiple stigmas can help to identify how these dynamics may limit access to biomedical HIV prevention among male sex workers, as well as suggesting strategies for addressing stigmas to improve the delivery of PrEP and other HIV prevention approaches in this population.


Asunto(s)
Infecciones por VIH/prevención & control , Homofobia/psicología , Homosexualidad Masculina/psicología , Relaciones Médico-Paciente , Autorrevelación , Trabajadores Sexuales/psicología , Confianza/psicología , Sexo Inseguro/psicología , Adulto , Anciano , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/psicología , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Profilaxis Pre-Exposición , Investigación Cualitativa , Adulto Joven
17.
ISME J ; 9(4): 894-908, 2015 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-25325380

RESUMEN

Atmospheric carbon dioxide (CO2) levels are rapidly rising causing an increase in the partial pressure of CO2 (pCO2) in the ocean and a reduction in pH known as ocean acidification (OA). Natural volcanic seeps in Papua New Guinea expel 99% pure CO2 and thereby offer a unique opportunity to explore the effects of OA in situ. The corals Acropora millepora and Porites cylindrica were less abundant and hosted significantly different microbial communities at the CO2 seep than at nearby control sites <500 m away. A primary driver of microbial differences in A. millepora was a 50% reduction of symbiotic Endozoicomonas. This loss of symbiotic taxa from corals at the CO2 seep highlights a potential hurdle for corals to overcome if they are to adapt to and survive OA. In contrast, the two sponges Coelocarteria singaporensis and Cinachyra sp. were ∼ 40-fold more abundant at the seep and hosted a significantly higher relative abundance of Synechococcus than sponges at control sites. The increase in photosynthetic microbes at the seep potentially provides these species with a nutritional benefit and enhanced scope for growth under future climate scenarios (thus, flexibility in symbiosis may lead to a larger niche breadth). The microbial community in the apparently pCO2-sensitive sponge species S. massa was not significantly different between sites. These data show that responses to elevated pCO2 are species-specific and that the stability and flexibility of microbial partnerships may have an important role in shaping and contributing to the fitness and success of some hosts.


Asunto(s)
Antozoos/microbiología , Bacterias/metabolismo , Dióxido de Carbono/análisis , Poríferos/microbiología , Agua de Mar/microbiología , Erupciones Volcánicas/análisis , Animales , Antozoos/fisiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Dióxido de Carbono/metabolismo , Fotosíntesis , Poríferos/fisiología , Agua de Mar/química , Simbiosis
18.
Am J Prev Med ; 48(2): 179-182, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25442225

RESUMEN

BACKGROUND: Physical activity interventions designed for Latinas have shown short-term behavior change, but longer-term change and maintenance is rarely measured. PURPOSE: To assess physical activity change at 12 months, following 6-month tapered completion of an RCT of a physical activity intervention for Latinas. METHODS: Two hundred sixty-six underactive (<60 minutes/week physical activity) Latinas were randomized to an individually tailored, culturally and linguistically adapted physical activity intervention, or a wellness contact control. Participants received the materials through the mail for 6 months, then received booster doses at 8, 10, and 12 months. Minutes per week of moderate to vigorous physical activity were measured by the 7-Day Physical Activity Recall interview at baseline and 6 and 12 months. Data were collected at Brown University between 2009 and 2013, and analyses were conducted in 2013. RESULTS: At 12 months, increases in moderate to vigorous physical activity were significantly greater in the intervention than in the wellness group (mean difference=52 minutes/week, SE=9.38, p<0.01), with both groups showing slight increases in moderate to vigorous physical activity from 6 to 12 months. Intervention participants were also more likely to meet national moderate to vigorous physical activity guidelines (OR=3.14, p=0.01). CONCLUSIONS: The intervention was more effective than the wellness control at 12 months, and physical activity increases from baseline to 6 months were maintained, suggesting the intervention may lead to sustainable behavior change. TRIAL REGISTRATION: This study is registered at Clinicaltrials.gov NCT01583140.


Asunto(s)
Conductas Relacionadas con la Salud , Hispánicos o Latinos , Actividad Motora , Estudios de Seguimiento , Promoción de la Salud/métodos , Humanos , New England
19.
PLoS One ; 9(11): e112425, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25386746

RESUMEN

BACKGROUND: Pre-exposure prophylaxis (PrEP) is a promising strategy for HIV prevention among men who have sex with men (MSM) and men who engage in sex work. But access will require routine HIV testing and contacts with healthcare providers. This study investigated men's healthcare and HIV testing experiences to inform PrEP implementation. METHODS: We conducted 8 focus groups (n = 38) in 2012 and 56 in-depth qualitative interviews in 2013-14 with male sex workers (MSWs) (n = 31) and other MSM (n = 25) in Providence, RI. MSWs primarily met clients in street-based sex work venues. Facilitators asked participants about access to healthcare and HIV/STI testing, healthcare needs, and preferred PrEP providers. RESULTS: MSWs primarily accessed care in emergency rooms (ERs), substance use clinics, correctional institutions, and walk-in clinics. Rates of HIV testing were high, but MSWs reported low access to other STI testing, low insurance coverage, and unmet healthcare needs including primary care, substance use treatment, and mental health services. MSM not engaging in sex work were more likely to report access to primary and specialist care. Rates of HIV testing among these MSM were slightly lower, but they reported more STI testing, more insurance coverage, and fewer unmet needs. Preferred PrEP providers for both groups included primary care physicians, infectious disease specialists, and psychiatrists. MSWs were also willing to access PrEP in substance use treatment and ER settings. CONCLUSIONS: PrEP outreach efforts for MSWs and other MSM should engage diverse providers in many settings, including mental health and substance use treatment, ERs, needle exchanges, correctional institutions, and HIV testing centers. Access to PrEP will require financial assistance, but can build on existing healthcare contacts for both populations.


Asunto(s)
Infecciones por VIH/prevención & control , Accesibilidad a los Servicios de Salud , Profilaxis Pre-Exposición , Trabajadores Sexuales , Enfermedades de Transmisión Sexual/prevención & control , Adulto , Instituciones de Atención Ambulatoria , Atención a la Salud , Infecciones por VIH/diagnóstico , Costos de la Atención en Salud , Homosexualidad Masculina , Humanos , Cobertura del Seguro , Masculino , Hombres , Servicios de Salud Mental , Aceptación de la Atención de Salud , Rhode Island , Trabajo Sexual , Enfermedades de Transmisión Sexual/diagnóstico , Centros de Tratamiento de Abuso de Sustancias , Estados Unidos
20.
J Int AIDS Soc ; 17(3 Suppl 2): 19158, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25224617

RESUMEN

INTRODUCTION: Product adherence and its measurement have emerged as a critical challenge in the evaluation of new HIV prevention technologies. Long-acting ARV-based vaginal rings may simplify use instructions and require less user behaviour, thereby facilitating adherence. One ARV-based ring is in efficacy trials and others, including multipurpose rings, are in the pipeline. Participant motivations, counselling support and measurement challenges during ring trials must still be addressed. In previous HIV prevention trials, this has been done largely using descriptive and post-hoc methods that are highly variable and minimally evaluated. We outline an interdisciplinary framework for systematically investigating promising strategies to support product uptake and adherence, and to measure adherence in the context of randomized, blinded clinical trials. DISCUSSION: The interdisciplinary framework highlights the dual use of adherence measurement (i.e. to provide feedback during trial implementation and to inform interpretation of trial findings) and underscores the complex pathways that connect measurement, adherence support and enacted adherence behaviour. Three inter-related approaches are highlighted: 1) adherence support - sequential efforts to define motivators of study product adherence and to develop, test, refine and evaluate adherence support messages; 2) self-reported psychometric measures - creation of valid and generalizable measures based in easily administered scales that capture vaginal ring use with improved predictive ability at screening, baseline and follow-up that better engage participants in reporting adherence; and 3) more objective measurement of adherence - real-time adherence monitoring and cumulative measurement to correlate adherence with overall product effectiveness through innovative designs, models and prototypes using electronic and biometric technologies to detect ring insertion and/or removal or expulsion. Coordinating research along these three pathways will result in a comprehensive approach to product adherence within clinical trials. CONCLUSIONS: Better measurement of adherence will not, by itself, ensure that future effectiveness trials will be able to address the most basic question: if the product is used per instructions, will it prevent HIV transmission? The challenges to adherence measurement must be addressed as one component of a more integrated system that has as its central focus adherence as a behaviour emerging from the social context of the user.


Asunto(s)
Antirretrovirales/administración & dosificación , Quimioprevención/métodos , Dispositivos Anticonceptivos Femeninos , Infecciones por VIH/prevención & control , Cumplimiento de la Medicación , Profilaxis Pre-Exposición/métodos , Femenino , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
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