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711.

Background

Risks for methicillin‐resistant Staphylococcus aureus (MRSA) among those with HIV infection have been found to vary, and the epidemiology of USA‐300 community‐acquired (CA) MRSA has not been adequately described.

Methods

We conducted a retrospective review of HIV‐infected out‐patients from January 2002 to December 2007 and employed multivariate logistic regression (MLR) to identify risks for MRSA colonization or infection. Pulsed‐field gel electrophoresis (PFGE) was used to identify USA‐300 strains. Results Seventy‐two (8%) of 900 HIV‐infected patients were colonized or infected with MRSA. MLR identified antibiotic exposure within the past year [odds ratio (OR) 3.4; 95% confidence interval (CI) 1.5–7.7] and nadir CD4 count <200 cells/μL (OR 2.5; 95% CI 1.2–5.3) as risks for MRSA colonization or infection. Receipt of antiretroviral therapy (ART) within the past year was associated with decreased risk (OR 0.16; 95% CI 0.07–0.4). Eighty‐nine percent of available strains were USA‐300. MLR identified skin or soft tissue infection (SSTI) as the only predictor for infection with USA‐300 (OR 5.9; 95% CI 1.4–24.3). Conclusion Significant risks for MRSA among HIV‐infected patients were CD4 count nadir <200 cells/μL and antibiotic exposure. Only the presence of an SSTI was associated with having USA‐300, and thus the use of patient characteristics to predict those with USA‐300 was limited. In addition, ART within the previous year significantly reduced the risk of MRSA colonization or infection.
  相似文献   
712.

Background

Maturation of enterocytes along the small intestinal crypt-villus axis is associated with significant changes in gene expression profiles. fls485 coding a putative chaperone protein has been recently suggested as a gene involved in this process. The aim of the present study was to analyze fls485 expression in human small intestinal mucosa.

Methods

fls485 expression in purified normal or intestinal mucosa affected with celiac disease was investigated with a molecular approach including qRT-PCR, Western blotting, and expression strategies. Molecular data were corroborated with several in situ techniques and usage of newly synthesized mouse monoclonal antibodies.

Results

fls485 mRNA expression was preferentially found in enterocytes and chromaffine cells of human intestinal mucosa as well as in several cell lines including Rko, Lovo, and CaCo2 cells. Western blot analysis with our new anti-fls485 antibodies revealed at least two fls485 proteins. In a functional CaCo2 model, an increase in fls485 expression was paralleled by cellular maturation stage. Immunohistochemistry demonstrated fls485 as a cytosolic protein with a slightly increasing expression gradient along the crypt-villus axis which was impaired in celiac disease Marsh IIIa-c.

Conclusions

Expression and synthesis of fls485 are found in surface lining epithelia of normal human intestinal mucosa and deriving epithelial cell lines. An interdependence of enterocyte differentiation along the crypt-villus axis and fls485 chaperone activity might be possible.  相似文献   
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Selvanathan SK, Shenton A, Ferner R, Wallace AJ, Huson SM, Ramsden RT, Evans DG. Further genotype–phenotype correlations in neurofibromatosis 2. Neurofibromatosis 2 (NF2) is caused by mutations in the NF2 gene predisposing carriers to develop nervous system tumours. Different NF2 mutations result in either loss/reduced protein function or gain of protein function (abnormally behaving mutant allele i.e. truncated protein potentially causing dominant negative effect). We present a comparison between the clinical presentations of patients with mutations that are predicted to produce truncated protein (nonsense/frameshift mutations) to those that results in loss of protein expression (large deletions) to elucidate further genotype–phenotype correlations in NF2. Patients with nonsense/frameshift mutations have a younger age of diagnosis and a higher prevalence/proportion of meningiomas (p = 0.002, p = 0.014), spinal tumours (p = 0.004, p = 0.004) and non‐VIII cranial nerve tumours (p = 0.006, p = 0.003). We also found younger age of diagnosis of vestibular schwannomas (p = 0.007), higher mean numbers of cutaneous lesions (p = 0.003) and spinal tumours (p = 0.006) in these patients. With respect to NF2 symptoms, we found younger age of onset of hearing loss (p = 0.010), tinnitus (p = 0.002), paraesthesiae (p = 0.073), wasting and weakness (p = 0.001) and headaches (p = 0.049) in patients with nonsense/frameshift mutations. Our comparison shows, additional, new correlations between mutations in the NF2 gene and the NF2 disease phenotype, and this further confirms that nonsense/frameshift mutations are associated with more severe NF2 symptoms. Therefore patients with this class of NF2 mutation should be followed up closely.  相似文献   
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Minoru Nakagawa  MD    Kenji Sugiu  MD    Koji Tokunaga  MD    Kohei Tsuda  RT    Matsuhiro Imaoka  RT    Atsushi Kawahara  RT    Kenjiro Fujiwara  MD 《Journal of neuroimaging》2009,19(2):179-182
The authors reported a case of a dural arteriovenous fistula (DAVF) in the left transverse-sigmoid sinus, in which 3-dimensional computed tomography (CT) angiograms (3D-CTAs) by a 64-section multidetector row CT scanner were useful for its diagnosis and treatment. The DAVF in the left transverse-sigmoid sinus appeared on the digital subtraction angiogram. 3D-CTAs were obtained by a 64-section multidetector row CT scanner before an endovascular treatment. The feeders and draining veins of the DAVF were clearly demonstrated on the 3D-CTAs, which clarified the relationship between the normal dural sinuses and DAVF. The DAVF was successfully treated with endovascular surgery, a transvenous embolization through the mastoid emissary vein, which was easily detected by using the 3D-CTA, showing both the subcutaneous vein and calvalium. 3D-CTAs by a 64-section multidetector row CT scanner are useful for both diagnosis and treatment of DAVFs.  相似文献   
718.
Although dementia is increasingly recognized as a common feature in Parkinson's disease (PD), its pathological substrate remains unknown. We conducted cross‐sectional and longitudinal brain perfusion SPECT analyses to explore changes during the course of developing dementia in PD. Fifty‐five patients originally diagnosed with PD were imaged in the cross‐sectional study. Twenty‐one of these, nine without dementia and 12 with dementia (PDD), were included in the longitudinal study to observe perfusion changes during the course of their disease. Data were analyzed using three‐dimensional stereotactic surface projection SPECT analysis. The UK Parkinson's Disease Society Brain Bank criteria were used to diagnose PD and the revised criteria for the clinical diagnosis of dementia with Lewy bodies for PDD. The cross‐sectional study showed that patients with PDD had significantly reduced perfusion in the right posterior cingulate, the right precuneus and the left posterior cingulate area. In the longitudinal study, significantly reduced perfusion was observed in the left anterior frontal gyrus in PD without dementia, and in the right inferior parietal lobule in those that developed PDD. We suggest that a relationship exists between developing dementia in PDD and reduced perfusion in the posterior parietal area. © 2009 Movement Disorder Society  相似文献   
719.
This study compared cortisol concentrations yielded using three saliva collection methods (passive drool, salivette, and sorbette) in both in vitro and in vivo conditions, as well as method acceptability for a sample of children (n = 39) with High Functioning Autism Spectrum Disorders. No cortisol concentration differences were observed between passive and sorbette samples obtained in vitro or in vivo. The salivette derived concentration was lower than the other two methods for the in vitro derived comparisons but did not differ from the other methods when collected in vivo. Cross-day comparison for the salivettes was also found to differ significantly, whereas the cross-day comparisons did not differ for the passive method or the sorbette method. Overall, passive drool and sorbettes were found to produce similar and stable readings of cortisol, whereas the salivette yielded unstable and variable concentrations. Ratings suggested that the children generally perceived all methods as acceptable.  相似文献   
720.
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