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Beryl A. Koblin Shannon Grant Victoria Frye Hillary Superak Brittany Sanchez Debbie Lucy Debora Dunbar Parrie Graham Tamra Madenwald Gina Escamilia Edith Swann Cecilia Morgan Richard M. Novak Ian Frank 《Journal of urban health》2015,92(3):572-583
Limited data are available on the longitudinal occurrence of syndemic factors among women at risk for HIV infection in the USA and how these factors relate to sexual risk over time. HVTN 906 was a longitudinal study enrolling 799 HIV-uninfected women in three cities. Assessments were done at baseline, 6, 12, and 18 months to assess syndemic factors (low education, low income, unemployment, lack of health insurance, housing instability, substance use, heavy alcohol use, partner violence, incarceration) and sexual risk outcomes. For each sexual risk outcome, a GEE model was fit with syndemic factors or syndemic score (defined as sum of binary syndemics, ranging from 0 to 9), visit, study site, age and race/ethnicity as predictors to examine the multivariable association between syndemic factors and outcomes over time. Odds of unprotected sex while drunk or high were significantly higher when women reported lack of health insurance, substance and heavy alcohol use and partner violence. Housing instability, substance and heavy alcohol use, partner violence and recent incarceration were associated with higher odds of having multiple sexual partners. Odds of sex exchange were significantly higher in the presence of unemployment, housing instability, low education, lack of health insurance, substance and heavy alcohol use, partner violence and incarceration. Housing instability, substance and heavy alcohol use, and partner violence were significantly associated with higher odds of unprotected anal sex. Odds of having a recent STI were significantly higher when women reported housing instability and partner violence. There were significantly higher odds of the reporting of any risk outcomes during follow-up with higher syndemic score. This study highlights a group of women experiencing multiple poor social and health outcomes who need to be the focus of comprehensive interventions. 相似文献
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beta-Endorphin: stability, clearance behavior, and entry into the central nervous system after intravenous injection of the tritiated peptide in rats and rabbits. 总被引:1,自引:1,他引:1
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R A Houghten R W Swann C H Li 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(8):4588-4591
Rabbits and rats were given intravenous injections of tritiated human beta-endorphin. The levels of beta-endorphin were followed by the decrease in radioactivity in the plasma of rats or rabbits and by the increase in radioactivity in the cerebrospinal fluid of the rabbit. The results were identical with the tritium label on either tyrosine-1 or -27. The plasma distribution times were 2 and 5 min in the rat and rabbit, respectively, with a later clearance time of approximately 1-8 hr. In the rat, approximately 50% of the radioactivity in the plasma was found to be intact human beta-endorphin 45 min after injection. Radioactivity appeared in the cerebrospinal fluid of the rabbit within 30 sec after injection and reached a plateau in approximately 60-90 min after injection. Approximately 75% of the radioactivity in the cerebrospinal fluid of the rabbit was intact human beta-endorphin. In the brain hemispheres of the rat and the rabbit, the only significant radiolabeled product was found to be radioactive tyrosine. Moreover, rat plasma levels of beta-endorphin decreased dramatically after hypophysectomy, which only slightly lowered the levels in the brain. It appears that beta-endorphin, upon entry into the plasma, is either not significantly taken up into the brain or is broken down with extreme rapidity upon entry into the brain, although it apparently does enter the cerebrospinal fluid. 相似文献
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George E. A. Swann Virginia N. Panizzo Sebastiano Piccolroaz Vanessa Pashley Matthew S. A. Horstwood Sarah Roberts Elena Vologina Natalia Piotrowska Michael Sturm Andre Zhdanov Nikolay Granin Charlotte Norman Suzanne McGowan Anson W. Mackay 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(44):27211
Lake Baikal, lying in a rift zone in southeastern Siberia, is the world''s oldest, deepest, and most voluminous lake that began to form over 30 million years ago. Cited as the “most outstanding example of a freshwater ecosystem” and designated a World Heritage Site in 1996 due to its high level of endemicity, the lake and its ecosystem have become increasingly threatened by both climate change and anthropogenic disturbance. Here, we present a record of nutrient cycling in the lake, derived from the silicon isotope composition of diatoms, which dominate aquatic primary productivity. Using historical records from the region, we assess the extent to which natural and anthropogenic factors have altered biogeochemical cycling in the lake over the last 2,000 y. We show that rates of nutrient supply from deep waters to the photic zone have dramatically increased since the mid-19th century in response to changing wind dynamics, reduced ice cover, and their associated impact on limnological processes in the lake. With stressors linked to untreated sewage and catchment development also now impacting the near-shore region of Lake Baikal, the resilience of the lake’s highly endemic ecosystem to ongoing and future disturbance is increasingly uncertain.Ancient lakes have long been associated with both high levels of biodiversity and endemicity. However, they are also being threatened by anthropogenic forcings that have led to impacts ranging from the warming of lake waters (1), hydrological modifications (2), increases in aquatic toxicity (3), and declining endemic populations due to introductions of nonnative species (4). With global populations increasingly reliant on large and ancient lakes for ecosystem services, the biodiversity (5) and value of aquatic systems to society (6), particularly in ancient lake systems (7), are at risk. Lake Baikal (Russia) is an exceptional example of an ancient lake (Fig. 1). In addition to containing ∼20% of global surface freshwater, the lake is characterized by its high degree of biodiversity with over 2,500 flora and fauna, the majority of which are endemic (8). This has been attributed to the lake’s age and fully oxygenated water column, driven by seasonal overturning and deep water renewal (9, 10) that sustains an almost completely endemic deep water fauna (8).Open in a separate windowFig. 1.Location of Lake Baikal and its catchment (gray) together with the location of World Meteorological Organization station in Irkutsk, major catchment rivers (brown), coring sites (BAIK13-1, BAIK13-4), and sites providing additional data used in this study (BAIK13-7).Concerns exist over the future health of this unique ecosystem, amid evidence of extensive shoreline eutrophication (11, 12) and climate-induced shifts in primary productivity (13, 14). Together, these changes have impacted organisms ranging from sponges and gastropods to ciliates, flagellates, and algal communities (15). Given the likelihood of future anthropogenic disturbance on Lake Baikal, further disrupting productivity exchanges through the lake’s food web, there is a need to place these contemporary observations into their historical setting. In Lake Baikal, we have evidence that algal communities have undergone rapid multidecadal to multicentennial timescale changes over the last 2,000 y (16). However, there is a need to also gain a clearer insight into how biogeochemical and nutrient cycling has altered over the same timescale, both to contextualize natural and anthropogenic drivers of change and to understand the susceptibility of the lake’s ecosystem to further alteration under different climate states (17). Annual primary productivity in Lake Baikal is ultimately regulated by photic zone nutrient availability, in addition to ice/snow cover, which regulates light availability for photosynthesis (10, 18). Here, by analyzing the silicon isotope composition of diatom silica (δ30Sidiatom), we show that nutrient supply to the surface waters of Lake Baikal has rapidly increased through the 20th and 21st centuries coincident with increased wind-driven Ekman transport and reduced ice cover. These changes in photic zone nutrient availability have the potential to alter resource competition and prey–predator interactions across the lake (15, 19). 相似文献
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Deborah Moncrieff William Keith Maria Abramson Alicia Swann 《International journal of audiology》2016,55(6):333-345
Children (n?=?141) referred to 5 clinical sites for auditory processing disorder assessment were tested with two dichotic listening tests, one with word pairs and the other with pairs of digits, as part of a comprehensive diagnostic battery. Scores from the Randomized Dichotic Digits Test and the Dichotic Words Test were compared to age-appropriate norms and used to place children into one of four diagnostic categories (normal, dichotic dysaudia, amblyaudia, or amblyaudia plus) or to identify them as undiagnosed. Results from the two dichotic tests led to diagnosis of 56% of the children tested, leaving 44% undiagnosed. When results from a third dichotic listening test were used as a tie-breaker among originally undiagnosed children, a total of 79% of the children’s scores were placed into diagnostic categories (13% normal, 19% dichotic dysaudia, 35% amblyaudia, 12% amblyaudia plus). Amblyaudia, a binaural integration deficit evident only from dichotic listening test results, was most prevalent (35%?+?12%?=?47%) in this population of children suspected of auditory processing weaknesses. Since amblyaudia responds to treatment with Auditory Rehabilitation for Interaural Asymmetry (ARIA), clinicians are guided through the protocol for identifying diagnostic categories so that they can make appropriate referrals for rehabilitation. 相似文献
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