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221.
We describe two cases in Brazil of human subcutaneous infections due to Phaeoacremonium spp. The first case was caused by Phaeoacremonium aleophilum. The patient presented with a unique fistulized nodule on the left ankle. The fungus was detected by direct microscopic examination and was isolated repeatedly from material collected from the lesion. This is the first reported case of human infection caused by this fungus. The second case was caused by Phaeoacremonium rubrigenum. The patient presented with multiple nodules around the left ankle and foot. The fungus was detected by direct examination of pus and histological sections of the nodules. It was repeatedly isolated from the clinical specimens. This is the second reported case of human infection caused by this species.  相似文献   
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BACKGROUND: Evidence suggests that "glucose effectiveness," (SG) or the effect of glucose per se to enhance net glucose disposal, may be at least as important as the insulin sensitivity index (SI) in the assessment of glucose tolerance. Our objective was to study the relationship of SG and SI parameters to left ventricular mass in a group of untreated, nondiabetic, and nonobese subjects recently diagnosed with stage I or high-normal blood pressure (BP). METHODS: In this sample of subjects, among whom the expected prevalence of insulin resistance is low, we assessed SG and SI parameters using the intravenous glucose tolerance test and minimal model analysis. We also measured left ventricular mass (LVM) index and diastolic function by echocardiography. RESULTS: We observed a strong relationship between SG and LVM index (r = -0.61, P <.0001). Patients with left ventricular hypertrophy (LVH) had lower SG than those without LVH (0.1114 +/- 0.04 v 0.2088 +/- 0.08 x 10(-1). min(-1), P <.001). In contrast, patients below the lowest quartile of the SG parameter distribution had higher LVM index (126.4 +/- 23.1 v 94.8 +/- 22.3 g/m(2), P <.001) and also had higher prevalence of LVH than the other patients (P <.0001). The SI related only to diastolic dysfunction, suggesting that SG may be an earlier marker of LVH than SI in hypertension. CONCLUSION: In this sample of nonobese and glucose-tolerant subjects with an early stage of hypertension, SG but not SI was related to LVM.  相似文献   
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Carbon nanotubes (CNT) have been reported to elicit toxic responses in vitro and in vivo, ascribed so far to metal contamination, CNT length, degree of oxidation, or extent of hydrophilicity. To examine how structural properties may modulate the toxicity of CNT, one preparation of multiwall CNT has been modified (i) by grinding (introducing structural defects) and subsequently heating either in a vacuum at 600 degrees C (causing reduction of oxygenated carbon functionalities and reduction of metallic oxides) or in an inert atmosphere at 2400 degrees C (causing elimination of metals and annealing of defects) and (ii) by heating at 2400 degrees C in an inert atmosphere and subsequently grinding the thermally treated CNT (introducing defects in a metal-deprived carbon framework). The presence of framework and surface defects, metals, and oxygenated functionalities was monitored by means of a set of techniques, including micro-Raman spectroscopy, adsorption calorimetry, X-ray photoelectron spectroscopy, inductively coupled plasma mass spectrometry, and atomic emission spectroscopy. Contrary to traditional toxicants, such as asbestos, CNT may quench rather than generate oxygenated free radicals. The potential of the modified CNT to scavenge hydroxyl radicals was thus evaluated by means of electron spin resonance spectroscopy (spin trapping). The original ground material exhibited a scavenging activity toward hydroxyl radicals, which was eliminated by heating at 2400 degrees C but restored upon grinding. This scavenging activity, related to the presence of defects, appears to go paired with the genotoxic and inflammatory potential of CNT reported in the companion paper. Thus, defects may be one of the major factors governing the toxic potential of CNT.  相似文献   
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We evaluated the in vitro killing activity of voriconazole (VRC) and posaconazole (PSC) against two clinical isolates of Candida guilliermondii. The two drugs showed fungistatic activity against both isolates and were effective in reducing kidney fungal burden in a neutropenic murine model of disseminated candidiasis in infected mice. PSC was significantly more effective than VRC against one of the strains. The serum levels of PSC and VRC were above the corresponding MICs for these isolates.  相似文献   
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Introduction

One of the most significant risk factors for the development of ovarian cancer (OC) is a genetic mutation in BRCA1 (breast cancer gene 1) or BRCA2. Here we describe the impact of previous and current guidance on BRCA testing practices and provide evidence about which characteristics best identify patients with OC and an underlying germline BRCA mutation.

Methods

A search was conducted for guidelines recommending genetic testing to identify constitutional pathogenic mutations in the BRCA genes. In addition, a systematic literature search of studies published in 2003–2015 was performed to assess BRCA mutation frequency in population-based OC patients unselected for patient characteristics (personal history, family history, and Ashkenazi Jewish ethnicity) and to describe the association of patient characteristics with BRCA mutation. Exclusively, studies assessing epithelial OC or invasive epithelial OC with full-gene screening of both BRCA1 and BRCA2 mutations were evaluated.

Results

Of 15 guidelines recommending genetic testing for OC patients, only 5 do not require co-occurrence of specific patient or family characteristics. Twenty-two full publications were identified that assessed germline BRCA mutation frequency in women with OC, utilizing a range of different full mutation detection methods. Germline BRCA mutation prevalence in patients with OC was 5.8–24.8%. Using criteria recommended in guidelines that are yet to be updated, we estimated that 27.5% of all germline BRCA mutations present in patients with OC may be missed because patients do not meet appropriate criteria.

Conclusion

With the availability of BRCA mutation-targeted therapies, identification of patients with OC with germline BRCA mutations has potential therapeutic consequences. For identified gene carriers, predictive testing to allow cancer prevention strategies, including bilateral salpingo-oophorectomy, provides wider benefit to identifying such gene carriers. Updating guidelines will increase the opportunity for targeted treatment among patients and risk reduction in relatives.

Funding

AstraZeneca
  相似文献   
229.

Background  

Fetal demise is an uncommon event encountered at MR imaging. When it occurs, recognition by the interpreting radiologist is important to initiate appropriate patient management.  相似文献   
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