87 research outputs found

    SNP identification of Africanized honey bees

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    Pubertal growth results from increased sex steroid and growth hormone (GH) secretion. Estrogens appear to play an important role in the regulation of pubertal growth in both girls and boys. In girls, however, estrogens cannot be the only sex steroids responsible for pubertal growth, as exogenous estrogens do not initiate a complete growth spurt. We therefore investigated the levels of the different sex steroids and GH, and related them to pubertal growth. In addition, we studied the process of bone maturation and mineralization during this period. Levels of both estrogens and androgens were found to increase at the start of the female pubertal growth spurt, and it was demonstrated that height velocity is related to levels of GH, estradiol and androstenedione, but not dehydroepiandrosterone sulfate. In boys, GH, testosterone and estradiol increased at the time of peak height velocity. Bone mineralization increased as puberty began, and was associated with the increase in height velocity. Osteocalcin, a marker of bone formation, declined when height velocity decreased, although bone maturation progressed at a steady rate. We conclude, therefore, that in girls, the concerted actions of estradiol, GH and androstenedione play a role in the pubertal growth spurt, whereas in boys this role is fulfilled by testosterone, GH and estradiol. During puberty, an advanced rate of bone maturation with respect to cross-sectional standards is a physiological phenomenon

    Honeybee, Apis mellifera, guards use adaptive acceptance thresholds to limit worker reproductive parasitism

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    Keywords: acceptance threshold Apis mellifera guard honeybee queenless recognition robbing worker reproductive parasitism To protect their colonies from robbing by conspecifics, honeybees have evolved nest-guarding behaviour. Guards adjust their acceptance threshold so that, as the likelihood of robbing increases, fewer nonnestmates are admitted. In addition to the possibility of robbing, queenless colonies may be infiltrated by reproductively parasitic non-nestmates. We tested the hypothesis that queenless colonies would be more discriminatory of non-nestmates than queenright colonies. As predicted, queenless colonies accepted significantly fewer non-nestmates (from queenright colonies) than they did nestmates, whereas queenright colonies did not differentiate significantly between the two sources. This trend continued once laying workers became active in queenless colonies. Thus there is evidence that queenless colonies are more discerning against potential reproductive parasites than queenright colonies. We also tested the hypothesis that as the likelihood of an intruder being a reproductive parasite increased, guards would become less permissive of allowing it entrance to the colony. Queenright colonies accepted significantly more non-nestmates from queenright colonies (no active ovaries) than they did non-nestmates from queenless colonies (many with active ovaries). However, queenless colonies did not make this distinction. We suggest that to queenless colonies all non-nestmates are potential parasites.

    Genetic origins of honey bees (Apis mellifera) on Kangaroo Island and Norfolk Island (Australia) and the Kingdom of Tonga

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    International audienceAbstractWe examine the origin of honey bee (Apis mellifera) populations in Kangaroo Island (Australia), Norfolk Island (Australia) and the Kingdom of Tonga using a highly polymorphic mitochondrial DNA region and a panel of 37 single nucleotide polymorphisms that assigns ancestry to three evolutionary lineages: Eastern Europe, Western Europe and Africa. We also examine inbreeding coefficients and genetic variation using microsatellites and mitochondrial sequencing. The honey bees of Kangaroo Island have a high proportion of Eastern European ancestry (90.2%), consistent with claims that they are of the subspecies A. m. ligustica. The honey bees of Norfolk Island also had a majority of ancestry from Eastern Europe (73.1%) with some contribution from Western Europe (21.2%). The honey bees of Tonga are mainly of Western European (70.3%) origin with some Eastern European ancestry (27.4%). Despite the suspected severe bottlenecks experienced by these island population, inbreeding coefficients were low

    Test-retest reliability of the Short-Form McGill Pain Questionnaire

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    Objectives: No previous study has adequately demonstrated the test-retest reliability of the Short-Form McGill Pain Questionnaire, yet it is increasingly being used as a measure of pain. This study evaluates the test-retest reliability in patients with osteoarthritis. Methods: A prospective, observational cohort study was undertaken using serial evaluation of 57 patients at 2 time points. A sample of patients awaiting primary hip or knee joint replacement surgery were recruited in clinic or via mail (mean age 64.8 years). Short-Form McGill Pain Questionnaires were delivered by mail 5 days apart, and a supplementary questionnaire was completed on the second occasion to explore if the patients’ pain report had remained stable. Results: The intraclass correlation coefficient was used as an estimate of reliability. For the total, sensory, affective, and average pain scores, high intra-class correlations were demonstrated (0.96, 0.95, 0.88, and 0.89, respectively). The current pain component demonstrated a lower intraclass correlation of 0.75. The coefficient of repeatability was calculated as an estimation of the minimum metrically detectable change. The coefficients of repeatability for the total, sensory, affective, average, and current pain components were 5.2, 4.5, 2.8, 1.4 cm, and 1.4, respectively. Discussion: Problems of adequate completion of the Short-Form McGill Pain Questionnaire were highlighted in this sample, and supervision via telephone contact was required. Patients recruited in clinic who had practiced completing the Short-Form McGill Pain Questionnaire demonstrated fewer errors than those recruited by mail. The Short-Form McGill Pain Questionnaire was demonstrated to be a highly reliable measure of pain. These results should not be generalized to a more elderly population, as increasing age was correlated with greater variability of the sensory component scores.</p

    Increasing leadership capacity for HIV/AIDS programmes by strengthening public health epidemiology and management training in Zimbabwe

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    <p>Abstract</p> <p>Background</p> <p>Increased funding for global human immunodeficiency virus prevention and control in developing countries has created both a challenge and an opportunity for achieving long-term global health goals. This paper describes a programme in Zimbabwe aimed at responding more effectively to the HIV/AIDS epidemic by reinforcing a critical competence-based training institution and producing public health leaders.</p> <p>Methods</p> <p>The programme used new HIV/AIDS programme-specific funds to build on the assets of a local education institution to strengthen and expand the general public health leadership capacity in Zimbabwe, simultaneously ensuring that they were trained in HIV interventions.</p> <p>Results</p> <p>The programme increased both numbers of graduates and retention of faculty. The expanded HIV/AIDS curriculum was associated with a substantial increase in trainee projects related to HIV. The increased number of public health professionals has led to a number of practically trained persons working in public health leadership positions in the ministry, including in HIV/AIDS programmes.</p> <p>Conclusion</p> <p>Investment of a modest proportion of new HIV/AIDS resources in targeted public health leadership training programmes can assist in building capacity to lead and manage national HIV and other public health programmes.</p

    Massive X-ray screening reveals two allosteric drug binding sites of SARS-CoV-2 main protease

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    The coronavirus disease (COVID-19) caused by SARS-CoV-2 is creating tremendous health problems and economical challenges for mankind. To date, no effective drug is available to directly treat the disease and prevent virus spreading. In a search for a drug against COVID-19, we have performed a massive X-ray crystallographic screen of repurposing drug libraries containing 5953 individual compounds against the SARS-CoV-2 main protease (Mpro), which is a potent drug target as it is essential for the virus replication. In contrast to commonly applied X-ray fragment screening experiments with molecules of low complexity, our screen tested already approved drugs and drugs in clinical trials. From the three-dimensional protein structures, we identified 37 compounds binding to Mpro. In subsequent cell-based viral reduction assays, one peptidomimetic and five non-peptidic compounds showed antiviral activity at non-toxic concentrations. Interestingly, two compounds bind outside the active site to the native dimer interface in close proximity to the S1 binding pocket. Another compound binds in a cleft between the catalytic and dimerization domain of Mpro. Neither binding site is related to the enzymatic active site and both represent attractive targets for drug development against SARS-CoV-2. This X-ray screening approach thus has the potential to help deliver an approved drug on an accelerated time-scale for this and future pandemics

    X-ray screening identifies active site and allosteric inhibitors of SARS-CoV-2 main protease

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    The coronavirus disease (COVID-19) caused by SARS-CoV-2 is creating tremendous human suffering. To date, no effective drug is available to directly treat the disease. In a search for a drug against COVID-19, we have performed a high-throughput X-ray crystallographic screen of two repurposing drug libraries against the SARS-CoV-2 main protease (M^(pro)), which is essential for viral replication. In contrast to commonly applied X-ray fragment screening experiments with molecules of low complexity, our screen tested already approved drugs and drugs in clinical trials. From the three-dimensional protein structures, we identified 37 compounds that bind to M^(pro). In subsequent cell-based viral reduction assays, one peptidomimetic and six non-peptidic compounds showed antiviral activity at non-toxic concentrations. We identified two allosteric binding sites representing attractive targets for drug development against SARS-CoV-2

    Isolation, establishment, and characterization of ex vivo equine melanoma cell cultures

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    Gray horses spontaneously develop metastatic melanomas that resemble human disease, and this is often accompanied with metastasis to other organs. Unlike in other species, the establishment of primary equine melanoma cultures that could be used to develop new therapeutic approaches has remained a major challenge. The purpose of the study was to develop a protocol for routine isolation and cultivation of primary equine melanocytes. Melanoma tissues were excised from 13 horses under local anesthesia, mainly from the perianal area. The melanoma cells were isolated from the melanoma tissue by serial enzymatic digestion using dispase and collagenase. Out of the 13 excised melanomas, cell cultures from eight melanomas were established, which corresponded to a success rate 62%. These cells showed different degrees of melanin pigmentation. Characterization of these cells using confocal microscopy, FACs analysis and western blotting showed that they expressed melanoma-associated antigens; Melan-A, MAGE-1, and MAGE-3, and PCNA expression was higher in fast-proliferating isolates. The protocol we developed and established proved successful for routine isolation and cultivation of primary equine melanoma cells. This method provided a large number of primary equine melanoma cells that could be used to study new therapeutic approaches for treatment of equine melanomas

    Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.

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    Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant
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