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801.
Propionibacterium acnes is an anaerobic Gram-positive bacterium that forms part of the normal human cutaneous microbiota and is occasionally associated with inflammatory diseases (I. Kurokawa et al., Exp. Dermatol. 18:821-832, 2009). Here we present the complete genome sequence for the commercially available P. acnes type II reference strain ATCC 11828 (I. Nagy et al., Microbes Infect. 8:2195-2205, 2006) recovered from a subcutaneous abscess.  相似文献   
802.
803.
In a small village of Hungary, a human trichinellosis outbreak (affecting eight people) occurred in January-February, 2009. In the outbreak investigation (i) Trichinella spiralis larvae were detected in meat products derived from the pigs slaughtered in the backyard of one of the patients (a foxhunter) in December 2008, and in a brown rat captured in the same backyard; (ii) sera of 24 pigs held in 11 yards of the village and that of some dogs of the foxhunter were found Trichinella-positive; (iii) sera of five villagers who could not be infected in the particular outbreak were also found reactive in Trichinella-specific laboratory tests. The followings helped the rise of an outbreak: the geographical position and the presence of empty houses favoured the multiplication of rats; there was no extermination of rats in the previous years; there was no meat inspection; raw meat and improperly processed meat products were tasted at the pig-slaughter; villagers gave tastes to each other. People were informed on the symptoms, the way of transmission, and the possibilities of prevention of trichinellosis by experts. With the help of local authorities, all the properties including the grounds with empty houses were involved in the extermination of rodents.  相似文献   
804.
805.
A spectacular hypothesis was published recently, which suggested that the "helmet" (a dorsal thoracic sclerite that obscures most of the body) of treehoppers (Insecta: Hemiptera: Membracidae) is connected to the 1st thoracic segment (T1; prothorax) via a jointed articulation and therefore was a true appendage. Furthermore, the "helmet" was interpreted to share multiple characteristics with wings, which in extant pterygote insects are present only on the 2nd (T2) and 3rd (T3) thoracic segments. In this context, the "helmet" could be considered an evolutionary novelty. Although multiple lines of morphological evidence putatively supported the "helmet"-wing homology, the relationship of the "helmet" to other thoracic sclerites and muscles remained unclear. Our observations of exemplar thoraces of 10 hemipteran families reveal multiple misinterpretations relevant to the "helmet"-wing homology hypothesis as originally conceived: 1) the "helmet" actually represents T1 (excluding the fore legs); 2) the "T1 tergum" is actually the anterior dorsal area of T2; 3) the putative articulation between the "helmet" and T1 is actually the articulation between T1 and T2. We conclude that there is no dorsal, articulated appendage on the membracid T1. Although the posterior, flattened, cuticular evagination (PFE) of the membracid T1 does share structural and genetic attributes with wings, the PFE is actually widely distributed across Hemiptera. Hence, the presence of this structure in Membracidae is not an evolutionary novelty for this clade. We discuss this new interpretation of the membracid T1 and the challenges of interpreting and representing morphological data more broadly. We acknowledge that the lack of data standards for morphology is a contributing factor to misinterpreted results and offer an example for how one can reduce ambiguity in morphology by referencing anatomical concepts in published ontologies.  相似文献   
806.
The enantiomers of four unusual isoxazoline‐fused 2‐aminocyclopentanecarboxylic acids were directly separated on chiral stationary phases containing (+)‐(18‐crown‐6)‐2,3,11,12‐tetracarboxylic acid as chiral selector. The nature of the alcoholic modifier (MeOH, EtOH, IPA) exerted a great effect on the retention, whereas the selectivity and resolution did not change substantially. Two types of dependence of retention on alcohol content were detected: k1 increased continuously with increasing alcohol content or a U‐shaped retention curve was observed. A comparison of the chromatographic data obtained with HCOOH, AcOH, TFA, HClO4, H2SO4, or H3PO4 as acidic modifier at a constant concentration demonstrated that in most cases, larger k values were obtained on the application of AcOH or HCOOH, and an increase of the acid content resulted in a decrease of retention. Some mechanistic aspects of the chiral recognition process are discussed with respect to the structures of the analytes and selector. The sequence of elution of the enantiomers was determined in all cases. Chirality 24:817‐824, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
807.
In this study we investigated the kinetics of colonization, the host susceptibility and transmissibility of methicillin-resistant Staphylococcus aureus (MRSA) after nasal treatment of pigs with three different MRSA strains of distinctive clonal lineages (sequence type 398 [ST398], ST8, and ST9), and origin in weaning piglets. The colonization dose of 5.0 × 10(8) CFU/animal was determined in preliminary animal studies. A total of 57 piglets were randomly divided into four test groups and one control group. Each of three test groups was inoculated intranasally with either MRSA ST8, MRSA ST9, or MRSA ST398. The fourth group was a mixture of animals inoculated with MRSA ST398 and noninoculated "sentinel" animals. Clinical signs, the nasal, conjunctival, and skin colonization of MRSA, fecal excretion, and organ distribution of MRSA, as well as different environmental samples were examined. After nasal inoculation with MRSA piglets of all four test groups showed no clinical signs of an MRSA infection. MRSA was present on the nasal mucosa, skin, and conjunctiva in all four test groups, including sentinel animals. Likewise, fecal excretion and internal colonization of MRSA ST8, ST9, and ST398 could be shown in each group. However, fecal excretion and the colonization rate of the nasal mucosa with MRSA ST9 were significantly lower in the first days after infection than in test groups infected with ST8 and ST398. The results of this study suggest differences in colonization potential of the different MRSA types in pigs. Furthermore, colonization of lymph nodes (e.g., the ileocecal lymph node) with MRSA of the clonal lineage ST398 was demonstrated.  相似文献   
808.
Tailored therapy in lung cancer is one of the most exciting fields in translational research and also a nice example of fruitful collaboration between pulmonologists, clinical oncologists, pathologists and molecular biologists. This article, through a dialogue between a pathologist-clinician and a molecular biologist-pharmacologist, gives an overview about the most important questions on molecular targeted therapy in clinical practice, especially, EGFR-TKI treatment, EGFR activating mutations, as well as primary and acquired resistance.  相似文献   
809.
810.
Aspergillus nidulans var. roseus ATCC 58397 is an echinocandin B (ECB) producer ascomycete with great industrial importance. As demonstrated by ECB/caspofungin sensitivity assays, A. nidulans var. roseus does not possess any inherent resistance to echinocandins, and its tolerance to these lipopeptide antimycotics are even lower than those of the non-producer A. nidulans FGSC A4 strain. Under ECB producing conditions or ECB exposures, A. nidulans var. roseus induced its ECB tolerance via up-regulating elements of the chitin biosynthetic machinery and, hence, through changing dynamically the composition of its own cell wall. Importantly, although the specific β-1,3-glucan synthase activity was elevated, these changes reduced the β-glucan content of hyphae considerably, but the expression of fksA, encoding the catalytic subunit of β-1,3-glucan synthase, the putative target of echinocandins in the aspergilli, was not affected. These data suggest that compensatory chitin biosynthesis is the centerpiece of the induced ECB tolerance of A. nidulans var. roseus. It is important to note that the induced tolerance to ECB (although resulted in paradoxical growth at higher ECB concentrations) was accompanied with reduced growth rate and, under certain conditions, even sensitized the fungus to other stress-generating agents like SDS. We hypothesize that although ECB-resistant mutants may arise in vivo in A. nidulans var. roseus cultures, their widespread propagation is severely restricted by the disadvantageous physiological effects of such mutations.  相似文献   
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