271 research outputs found

    Sucrose as a Feeding Deterrent for Fruit-Eating Birds

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    Economic losses due to bird damage to small fruits such as blueberries, grapes, and cherries can be very high and are expected to increase in the future. The primary sugars in these fruits are glucose and fructose. Sucrose is present in very low concentrations only. Our research has unveiled a physiological trait common to many fruit-eating species in the phylogenetically related families Muscicapidae, Mirnidae, and Sturnidae. These birds are unable to digest sucrose because they lack the intestinal enzyme sucrase which hydrolyzes sucrose into glucose and fructose prior to absorption. In cage tests these birds prefer glucose and fructose to sucrose solutions and reject concentrated sucrose solutions and artificial gel fruits made with sucrose. Is it reasonable and feasible to attempt development of high-sucrose cultivars with the goal of deterring birds in fruit crops? Variation in the proportion of sucrose in mature fruits is present among strawberry, cherry, and blueberry cultivars. Consequently, genetic resources are available to develop high-sucrose cultivars through traditional breeding practices or bioengineering. We suggest that major fm i t-depredating species, such as American robins and European starlings, will avoid eating high-sucrose fruits in an agricultural setting provided that (1) sucrose concentration in these fruits is sufficiently high, (2) there is alternate food available, and (3) high-sucrose fruits are planted in relatively large stands. Despite the obvious need for more data, we believe that increasing the sucrose content of small-berried fruits is a promising direction in integrated pest management research that can result in substantial reductions in bird damage

    Measuring Population Transmission Potential for HIV: An Alternative Metric of Transmission Risk in Men who have Sex with Men (MSM) in the US

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    Background Various metrics for HIV burden and treatment success [e.g. HIV prevalence, community viral load (CVL), population viral load (PVL), percent of HIV-positive persons with undetectable viral load] have important public health limitations for understanding disparities. Methods and Findings Using data from an ongoing HIV incidence cohort of black and white men who have sex with men (MSM), we propose a new metric to measure the prevalence of those at risk of transmitting HIV and illustrate its value. …See full text for complete abstract

    The Comparability of Men Who Have Sex With Men Recruited From Venue-Time-Space Sampling and Facebook: A Cohort Study

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    Background: Recruiting valid samples of men who have sex with men (MSM) is a key component of the US human immunodeficiency virus (HIV) surveillance and of research studies seeking to improve HIV prevention for MSM. Social media, such as Facebook, may present an opportunity to reach broad samples of MSM, but the extent to which those samples are comparable with men recruited from venue-based, time-space sampling (VBTS) is unknown. Objective: The objective of this study was to assess the comparability of MSM recruited via VBTS and Facebook. Methods: HIV-negative and HIV-positive black and white MSM were recruited from June 2010 to December 2012 using VBTS and Facebook in Atlanta, GA. We compared the self-reported venue attendance, demographic characteristics, sexual and risk behaviors, history of HIV-testing, and HIV and sexually transmitted infection (STI) prevalence between Facebook- and VTBS-recruited MSM overall and by race. Multivariate logistic and negative binomial models estimated age/race adjusted ratios. The Kaplan-Meier method was used to assess 24-month retention. Results: We recruited 803 MSM, of whom 110 (34/110, 30.9% black MSM, 76/110, 69.1% white MSM) were recruited via Facebook and 693 (420/693, 60.6% black MSM, 273/693, 39.4% white MSM) were recruited through VTBS. Facebook recruits had high rates of venue attendance in the previous month (26/34, 77% among black and 71/76, 93% among white MSM; between-race P=.01). MSM recruited on Facebook were generally older, with significant age differences among black MSM (P=.02), but not white MSM (P=.14). … See full text for complete abstract

    Sulfa or Sulfone Prophylaxis and Geographic Region Predict Mutations in the Pneumocystis carinii Dihydropteroate Synthase Gene

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    To determine factors associated with mutations in the Pneumocystis carinii dihydropteroate synthase (DHPS) gene, a prospective study of human immunodeficiency virus (HIV)-infected patients with confirmed P. carinii pneumonia was conducted in Atlanta, Seattle, and San Francisco. Clinical information was obtained from patient interview and chart abstraction. DHPS genotype was determined from DNA sequencing. Overall, 76 (68.5%) of 111 patients had a mutant DHPS genotype, including 22 (81.5%) of 27 patients from San Francisco. In multivariate analysis, sulfa or sulfone prophylaxis and study site were independent predictors of a mutant genotype. Fourteen (53.8%) of 26 patients who were newly diagnosed with HIV infection and had never taken prophylaxis had a mutant genotype. The significance of geographic location as a risk factor for mutant genotype and the high proportion of mutant genotypes among persons never prescribed prophylaxis, including those newly diagnosed with HIV infection, provide indirect evidence that these mutations are transmitted from person to person either directly or through a common environmental source

    Sexual violence against children and adolescents in Brazil : a systematic review of the literature.

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    O prop?sito desse artigo foi realizar um levantamento sistematizado das pesquisas de p?s-gradua??o Strictu Sensu, contendo informa??es relevantes sobre a problem?tica da viol?ncia sexual contra crian?as e adolescentes no Brasil. Ap?s a sele??o filtrada de 46 trabalhos, foi poss?vel identificar a preval?ncia das pesquisas realizadas em Institui??es P?blicas de Ensino Superior (IFES) localizadas nas regi?es Nordeste e Sudeste. Em rela??o ao perfil das v?timas, prevalece a viol?ncia sexual contra meninas, e o risco de viol?ncia aumenta na medida em que estas se aproximam da adolesc?ncia (faixa entre 12 e 14 anos). Ficou bastante claro que a tem?tica deve ser entendida sob um aspecto multidisciplinar, havendo, assim, necessidade de articula??o entre os diversos atores sociais envolvidos na formula??o de pol?ticas p?blicas voltadas para prote??o das crian?as e adolescentes.We propose to conduct a systematic literature review of postgraduate research, which relevant information on the issue of sexual violence against children and adolescents in Brazil. After the selection of 46 researches, we identify the prevalence of research carried out in Public Institutions (IFES) located in the Northeast and Southeast regions. Regarding the profile of the victims, sexual violence against girls prevails, and the risk of violence increases as they approach adolescence (between 12 and 14 years old). It was quite clear that the theme should be understood from a multidisciplinary aspect, thus requiring articulation between the various social actors involved in the formulation of public policies aimed at protecting children and adolescents

    Advanced glycation end product cross-link breaker attenuates diabetes-induced cardiac dysfunction by improving sarcoplasmic reticulum calcium handling

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    Diabetic heart disease is a distinct clinical entity that can progress to heart failure and sudden death. However, the mechanisms responsible for the alterations in excitation-contraction coupling leading to cardiac dysfunction during diabetes are not well known. Hyperglycemia, the landmark of diabetes, leads to the formation of advanced glycation end products (AGEs) on long-lived proteins, including sarcoplasmic reticulum (SR) Ca2+ regulatory proteins. However, their pathogenic role on SR Ca2+ handling in cardiac myocytes is unknown. Therefore, we investigated whether an AGE cross-link breaker could prevent the alterations in SR Ca2+ cycling that lead to in vivo cardiac dysfunction during diabetes. Streptozotocin-induced diabetic rats were treated with alagebrium chloride (ALT-711) for 8 weeks and compared to age-matched placebo-treated diabetic rats and healthy rats. Cardiac function was assessed by echocardiographic examination. Ventricular myocytes were isolated to assess SR Ca2+ cycling by confocal imaging and quantitative Western blots. Diabetes resulted in in vivo cardiac dysfunction and ALT-711 therapy partially alleviated diastolic dysfunction by decreasing isovolumetric relaxation time and myocardial performance index (MPI) (by 27 and 41% vs. untreated diabetic rats, respectively, P < 0.05). In cardiac myocytes, diabetes-induced prolongation of cytosolic Ca2+ transient clearance by 43% and decreased SR Ca2+ load by 25% (P < 0.05); these parameters were partially improved after ALT-711 therapy. SERCA2a and RyR2 protein expression was significantly decreased in the myocardium of untreated diabetic rats (by 64 and 36% vs. controls, respectively, P < 0.05), but preserved in the treated diabetic group compared to controls. Collectively, our results suggest that, in a model of type 1 diabetes, AGE accumulation primarily impairs SR Ca2+ reuptake in cardiac myocytes and that long-term treatment with an AGE cross-link breaker partially normalized SR Ca2+ handling and improved diabetic cardiomyopathy.Peer reviewedPhysiological Science

    The APOGEE-2 Survey of the Orion Star Forming Complex: I. Target Selection and Validation with early observations

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    The Orion Star Forming Complex (OSFC) is a central target for the APOGEE-2 Young Cluster Survey. Existing membership catalogs span limited portions of the OSFC, reflecting the difficulty of selecting targets homogeneously across this extended, highly structured region. We have used data from wide field photometric surveys to produce a less biased parent sample of young stellar objects (YSOs) with infrared (IR) excesses indicative of warm circumstellar material or photometric variability at optical wavelengths across the full 420 square degrees extent of the OSFC. When restricted to YSO candidates with H < 12.4, to ensure S/N ~100 for a six visit source, this uniformly selected sample includes 1307 IR excess sources selected using criteria vetted by Koenig & Liesawitz and 990 optical variables identified in the Pan-STARRS1 3π\pi survey: 319 sources exhibit both optical variability and evidence of circumstellar disks through IR excess. Objects from this uniformly selected sample received the highest priority for targeting, but required fewer than half of the fibers on each APOGEE-2 plate. We fill the remaining fibers with previously confirmed and new color-magnitude selected candidate OSFC members. Radial velocity measurements from APOGEE-1 and new APOGEE-2 observations taken in the survey's first year indicate that ~90% of the uniformly selected targets have radial velocities consistent with Orion membership.The APOGEE-2 Orion survey will include >1100 bona fide YSOs whose uniform selection function will provide a robust sample for comparative analyses of the stellar populations and properties across all sub-regions of Orion.Comment: Accepted for publication in ApJ

    Effects of danicamtiv, a novel cardiac myosin activator, in heart failure with reduced ejection fraction: experimental data and clinical results from a phase 2a trial

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    Aims: Both left ventricular (LV) and left atrial (LA) dysfunction and remodelling contribute to adverse outcomes in heart failure with reduced ejection fraction (HFrEF). Danicamtiv is a novel, cardiac myosin activator that enhances cardiomyocyte contraction. Methods and results: We studied the effects of danicamtiv on LV and LA function in non‐clinical studies (ex vivo : skinned muscle fibres and myofibrils; in vivo : dogs with heart failure) and in a randomized, double‐blind, single‐ and multiple‐dose phase 2a trial in patients with stable HFrEF (placebo, n = 10; danicamtiv, n = 30; 50–100 mg twice daily for 7 days). Danicamtiv increased ATPase activity and calcium sensitivity in LV and LA myofibrils/muscle fibres. In dogs with heart failure, danicamtiv improved LV stroke volume (+10.6 mL, P &lt; 0.05) and LA emptying fraction (+10.7%, P &lt; 0.05). In patients with HFrEF (mean age 60 years, 25% women, ischaemic heart disease 48%, mean LV ejection fraction 32%), treatment‐emergent adverse events, mostly mild, were reported in 17 patients (57%) receiving danicamtiv and 4 patients (40%) receiving placebo. Danicamtiv (at plasma concentrations ≥2000 ng/mL) increased stroke volume (up to +7.8 mL, P &lt; 0.01), improved global longitudinal (up to −1.0%, P &lt; 0.05) and circumferential strain (up to −3.3%, P &lt; 0.01), decreased LA minimal volume index (up to −2.4 mL/m2, P &lt; 0.01) and increased LA function index (up to 6.1, P &lt; 0.01), when compared with placebo. Conclusions: Danicamtiv was well tolerated and improved LV systolic function in patients with HFrEF. A marked improvement in LA volume and function was also observed in patients with HFrEF, consistent with pre‐clinical findings of direct activation of LA contractility

    Neurons of the Dentate Molecular Layer in the Rabbit Hippocampus

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    The molecular layer of the dentate gyrus appears as the main entrance gate for information into the hippocampus, i.e., where the perforant path axons from the entorhinal cortex synapse onto the spines and dendrites of granule cells. A few dispersed neuronal somata appear intermingled in between and probably control the flow of information in this area. In rabbits, the number of neurons in the molecular layer increases in the first week of postnatal life and then stabilizes to appear permanent and heterogeneous over the individuals’ life span, including old animals. By means of Golgi impregnations, NADPH histochemistry, immunocytochemical stainings and intracellular labelings (lucifer yellow and biocytin injections), eight neuronal morphological types have been detected in the molecular layer of developing adult and old rabbits. Six of them appear as interneurons displaying smooth dendrites and GABA immunoreactivity: those here called as globoid, vertical, small horizontal, large horizontal, inverted pyramidal and polymorphic. Additionally there are two GABA negative types: the sarmentous and ectopic granular neurons. The distribution of the somata and dendritic trees of these neurons shows preferences for a definite sublayer of the molecular layer: small horizontal, sarmentous and inverted pyramidal neurons are preferably found in the outer third of the molecular layer; vertical, globoid and polymorph neurons locate the intermediate third, while large horizontal and ectopic granular neurons occupy the inner third or the juxtagranular molecular layer. Our results reveal substantial differences in the morphology and electrophysiological behaviour between each neuronal archetype in the dentate molecular layer, allowing us to propose a new classification for this neural population
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