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Mycetoma is a chronic infectious disease of the subcutaneous tissue with a high morbidity. This disease has been reported from countries between 30°N and 15°S since 1840 but the exact burden of disease is not known. It is currently unknown what the incidence, prevalence and the number of reported cases per year per country is. In order to estimate what the global burden of mycetoma is, a meta-analysis was performed. In total 50 studies were included, which resulted in a total of 8763 mycetoma cases. Most cases were found in men between 11 and 40 years of age. The foot was most commonly affected. Most cases were reported from Mexico, Sudan and India. Madurella mycetomatis was the most prevalent causative agent world-wide, followed by Actinomadura madurae, Streptomyces somaliensis, Actinomadura pelletieri, Nocardia brasiliensis and Nocardia asteroides. Although this study represents a first indication of the global burden on mycetoma, the actual burden is probably much higher. In this study only cases reported to literature could be used and most of these cases were found by searching archives from a single hospital in a single city of that country. By erecting (inter)national surveillance programs a more accurate estimation of the global burden on mycetoma can be obtained.  相似文献   
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Diverse communities of fungi and bacteria in deadwood mediate wood decay. While rates of decomposition vary greatly among woody species and spatially distinct habitats, the relative importance of these factors in structuring microbial communities and whether these shift over time remains largely unknown. We characterized fungal and bacterial diversity within pieces of deadwood that experienced 6.3–98.8% mass loss while decaying in common garden ‘rotplots’ in a temperate oak-hickory forest in the Ozark Highlands, MO, USA. Communities were isolated from 21 woody species that had been decomposing for 1–5 years in spatially distinct habitats at the landscape scale (top and bottom of watersheds) and within stems (top and bottom of stems). Microbial community structure varied more strongly with wood traits than with spatial locations, mirroring the relative role of these factors on decay rates on the same pieces of wood even after 5 years. Co-occurring fungal and bacterial communities persistently influenced one another independently from their shared environmental conditions. However, the relative influence of wood construction versus spatial locations differed between fungi and bacteria, suggesting that life history characteristics of these clades structure diversity differently across space and time in decomposing wood.  相似文献   
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Genetic transformation is a valuable and essential method that provides powerful insights into the gene function of microorganisms and contributes to the construction of engineered bacteria. Here, we developed a novel genetic transformation system to easily knock out a highly GC-rich gene (74.71% GC) from Burkholderia pyrrocinia JK-SH007, a biocontrol strain of poplar canker disease. This system revealed a reliable selectable marker (trimethoprim resistance gene, Tmp) and a simplified, efficient transformation method (6,363.64 CFU/μg, pHKT2) that was developed via freeze-thawing. The knockout recombineering of B. pyrrocinia JK-SH007 was achieved through a suicide plasmid with a three-fragment mutagenesis construct. The three-fragment cassette for mutagenesis was generated by overlap extension and touchdown PCRs and composed of Tmp flanked by GC-rich upstream and downstream fragments from B. pyrrocinia JK-SH007. The mutant strain (ΔBpEG), which was verified by PCR, lost 93.3% of its ability to degrade carboxymethyl cellulose over 40 days. Overall, this system may contribute to future research on B. pyrrocinia traits.  相似文献   
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While doctors generally enjoy considerable status, some believe that this is increasingly threatened by consumerism, managerialism, and competition from other health professions. Research into doctors’ perceptions of the changes occurring in medicine has provided some insights into how they perceive and respond to these changes but has generally failed to distinguish clearly between concerns about “status,” related to the entitlements associated with one’s position in a social hierarchy, and concerns about “respect,” related to being held in high regard for one’s moral qualities. In this article we explore doctors’ perceptions of the degree to which they are respected and their explanations for, and responses to, instances of perceived lack of respect. We conclude that doctors’ concerns about loss of respect need to be clearly distinguished from concerns about loss of status and that medical students need to be prepared for a changing social field in which others’ respect cannot be taken for granted.  相似文献   
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The pharmaceutical industry has been criticised for pervasive misconduct. These concerns have generally resulted in increasing regulation. While such regulation is no doubt necessary, it tends to assume that everyone working for pharmaceutical companies is equally motivated by commerce, without much understanding of the specific views and experiences of those who work in different parts of the industry. In order to gain a more nuanced picture of the work that goes on in the “medical affairs” departments of pharmaceutical companies, we conducted 15 semi-structured interviews with professionals working in medical departments of companies in Sydney, Australia. We show that this group of pharmaceutical professionals are committed to their responsibilities both to patients, research participants, and the public and to their companies. Despite the discrepancies between these commitments, our participants did not express much cognitive dissonance, and this appeared to stem from their use of two dialectically related strategies, one of which embraces commerce and the other of which resists the commercial imperative. We interpret these findings through the lens of institutional theory and consider their implications for pharmaceutical ethics and governance.  相似文献   
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