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71.
Staphylococcus epidermidis has emerged as the most important pathogen in infections related to indwelling medical devices, and although these infections are not life-threatening, their frequency and the fact that they are extremely difficult to treat represent a serious burden on the public health system. Treatment is complicated by specific antibiotic resistance genes and the formation of biofilms. Hence, novel therapeutic strategies are needed to fight these infections. A novel bacteriophage CUB-EPI_14 specific to the bacterial species S. epidermidis was isolated from sewage and characterized genomically and phenotypically. Its genome contains a total of 46,098 bp and 63 predicted genes, among which some have been associated with packaging and lysis-associated proteins, structural proteins, or DNA- and metabolism-associated proteins. No lysogeny-associated proteins or known virulence proteins were identified in the phage genome. CUB-EPI_14 showed stability over a wide range of temperatures (from −20 °C to 50 °C) and pH values (pH 3–pH 12) and a narrow host range against S. epidermidis. Potent antimicrobial and antibiofilm activities were observed when the phage was tested against a highly susceptible bacterial isolate. These encouraging results open the door to new therapeutic opportunities in the fight against resilient biofilm-associated infections caused by S. epidermidis.  相似文献   
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Botulinum neurotoxins (BoNTs) cause the life-threatening neurological illness botulism in humans and animals and are divided into seven serotypes (BoNT/A–G), of which serotypes A, B, E, and F cause the disease in humans. BoNTs are classified as “category A” bioterrorism threat agents and are relevant in the context of the Biological Weapons Convention. An international proficiency test (PT) was conducted to evaluate detection, quantification and discrimination capabilities of 23 expert laboratories from the health, food and security areas. Here we describe three immunological strategies that proved to be successful for the detection and quantification of BoNT/A, B, and E considering the restricted sample volume (1 mL) distributed. To analyze the samples qualitatively and quantitatively, the first strategy was based on sensitive immunoenzymatic and immunochromatographic assays for fast qualitative and quantitative analyses. In the second approach, a bead-based suspension array was used for screening followed by conventional ELISA for quantification. In the third approach, an ELISA plate format assay was used for serotype specific immunodetection of BoNT-cleaved substrates, detecting the activity of the light chain, rather than the toxin protein. The results provide guidance for further steps in quality assurance and highlight problems to address in the future.  相似文献   
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The novel sesquiterpene hydroquinone isoarenarol (1) and the known compound arenarol (2) were isolated from extracts of the marine sponge Dysidea arenaria Bergquist as part of a search for new protein kinase inhibitors. Both 1 and 2 showed potent and selective protein kinase inhibition in vitro.  相似文献   
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With the growing realisation that sexual violence poses pressing health and human rights concerns for men who have sex with men (MSM) and individuals on the trans-feminine spectrum, research has focused on the context in which sexual violence takes place. Rape myths and other perceptions of sexual violence affect the prevalence of perpetration and the availability of services and support for survivors. Little research has been conducted on rape myths among sexual and gender minority groups, especially in low- and middle-income countries. Two focus groups and 30 in-depth interviews were conducted with MSM and individuals on the trans-feminine spectrum in Ulaanbaatar, Mongolia. A number of rape myths previously noted to be prevalent among Western, heterosexual men, and women were expressed by participants, including the myth that males are never raped, rape as a cause of homosexuality or transgenderism, conceptualisations of prototypical rape as requiring overwhelming force, and victim blaming. However, many of these perceptions appeared to have different origins and effects in these populations. This study illustrates interesting similarities and differences compared to rape myths explored in Western, heterosexual male samples, and draws attention to the need to address community perceptions of sexual violence in sexual health and violence intervention programming.  相似文献   
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Youthful indoor tanning as few as ten sessions can increase the risk of melanoma by two to four times with each additional session adding another 2 % to the risk. Recent research estimates that indoor tanning can be linked to approximately 450,000 cases of skin cancer annually in the USA, Europe, and Australia. Despite these risks, indoor tanning remains popular with adolescents. This study tested the efficacy of a web-based skin cancer prevention intervention designed to reduce indoor tanning motivations in adolescent females. A nationally representative sample of 443 female teens was enrolled from an online panel into a two-arm, parallel group design, randomized controlled trial. Treatment participants received an appearance-focused intervention grounded in established health behavior change models. Controls viewed a teen alcohol prevention website. Outcome variables included willingness and intentions to indoor tan, willingness to sunless tan, and measures of indoor tanning attitudes and beliefs. The intervention decreased willingness and intentions to indoor tan and increased sunless tanning willingness relative to controls. We also examined indirect mechanisms of change through intervening variables (e.g., indoor tanning attitudes, norms, positive and negative expectancies) using the product of coefficient approach. The web-based intervention demonstrated efficacy in changing adolescent indoor tanning motivations and improving their orientation toward healthier alternatives. Results from the intervening variable analyses give guidance to future adolescent skin cancer prevention interventions.  相似文献   
80.
The use of genes for distinguishing classes of toxicity has become well established. In this paper we combine the reconstruction of a gene dysregulation network (GDN) with a classifier to assign unseen compounds to their appropriate class. Gene pairs in the GDN are dysregulated in the sense that they are linked by a common expression pattern in one class and differ in this pattern in another class. The classifier gives a quantitative measure on this difference by its prediction accuracy. As an in‐depth example, gene pairs were selected that were dysregulated between skin cells treated with either sensitizers or irritants. Pairs with known and novel markers were found such as HMOX1 and ZFAND2A, ATF3 and PPP1R15A, OXSR1 and HSPA1B, ZFP36 and MAFF. The resulting GDN proved biologically valid as it was well‐connected and enriched in known interactions, processes and common regulatory motifs for pairs. Classification accuracy was improved when compared with conventional classifiers. As the dysregulated patterns for heat shock responding genes proved to be distinct from those of other stress genes, we were able to formulate the hypothesis that heat shock genes play a specific role in sensitization, apart from other stress genes. In conclusion, our combined approach creates added value for classification‐based toxicogenomics by obtaining novel, well‐distinguishing and biologically interesting measures, suitable for the formulation of hypotheses on functional relationships between genes and their relevance for toxicity class differences. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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