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The usefulness to diagnose and monitor invasive candidiasis (IC) using beta-glucan (BG) and antibodies against Candida albicans germ tubes (CAGT) was evaluated in a twice-weekly screening of 35 episodes in neutropenic adults at high risk. Three proven IC and three probable IC were assessed. Diagnostic levels of both markers were detected in 100% of proven IC and in 66% of probable IC. Sensitivity, specificity, positive and negative predictive values of BG and anti-CAGT antibodies detection were 83.3%, 89.6%, 62.5% and 96.3%, and 83.3%, 86.2%, 55.5%, 96.1%, respectively. False positive reactions occurred at a rate of 10.3% and 13.8% for the detection of BG and anti-CAGT antibodies, respectively. However, the patients with false positive results were different by each test. Both tests anticipated the clinical and radiological diagnosis, and the initiation of antifungal therapy in most patients. Combination of both tests improved specificity and positive predictive value to 100%.  相似文献   
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MOTIVATION: Current projects for the massive characterization of proteomes are generating protein sequences and structures with unknown function. The difficulty of experimentally determining functionally important sites calls for the development of computational methods. The first techniques, based on the search for fully conserved positions in multiple sequence alignments (MSAs), were followed by methods for locating family-dependent conserved positions. These rely on the functional classification implicit in the alignment for locating these positions related with functional specificity. The next obvious step, still scarcely explored, is to detect these positions using a functional classification different from the one implicit in the sequence relationships between the proteins. Here, we present two new methods for locating functional positions which can incorporate an arbitrary external functional classification which may or may not coincide with the one implicit in the MSA. The Xdet method is able to use a functional classification with an associated hierarchy or similarity between functions to locate positions related to that classification. The MCdet method uses multivariate statistical analysis to locate positions responsible for each one of the functions within a multifunctional family. RESULTS: We applied the methods to different cases, illustrating scenarios where there is a disagreement between the functional and the phylogenetic relationships, and demonstrated their usefulness for the phylogeny-independent prediction of functional positions.  相似文献   
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Exposure of citrus fruit to frost often results in the development of freeze injury during their maturation in planta. This work was aimed to analyze changes in the biochemistry and enzymology of carbohydrate metabolism in freeze-injured orange fruit ( Citrus sinensis var. Valencia late) and the involvement of oxidative stress in frost damage. The activities of pyrophosphate-dependent phosphofructokinase, phosphoenolpyruvate carboxylase and several fermentative enzymes increased in frost-exposed (FE) fruit, while NADP-malic enzyme and the mitochondrial isoform of NAD-malate dehydrogenase showed a reduction in their activities. Western blot analysis indicated a correlation between activity levels and protein content. Respiration rate in whole fruit was reduced by 40%, whereas the flavedo showed a more pronounced decline (53%). Volatile compound (i.e. ethanol and acetaldehyde) content was significantly higher in FE fruit than in control, as was that of l -malate (three-fold). Additionally, FE fruit showed a marked decrease in the maturity index (24%) because of a higher titratable acidity (39%). Evidence is presented that oxidative stress is involved in freeze-induced damage of orange fruit, where oxidative damage to lipids and proteins, and a greater electrolyte leakage in the flavedo were also observed. The results suggest that freezing temperatures provoke a notable metabolic switch in citrus fruit toward a fermentative stage, resulting in low-quality fruits.  相似文献   
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We tested the effects of the aqueous extract of Petiveria alliacea leaves on acute and sub-chronic toxicity, hematocrit and blood glucose level and intestinal motility of male albino NGP mice of 20 to 25 g mean weight. Treatments were in all cases doses of 1,000 and 2,000 mg/kg animal weight and a control treatment with 0.5 ml distilled water, using 10 animals per treatment and administered orally every day (5 days per week). Experimental periods were 18 and 70 days for acute and sub chronic toxicity, respectively. No mortality nor any toxicity signs could be observed. A slight but significant increase in the glucose levels during the first three weeks was observed with the 1,000 mg/kg dose but not for the higher 2,000 mg/kg dose. After administering the doses once after a starving period of six hours, no significant differences in intestinal motility could be found.  相似文献   
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BackgroundTriple negative breast cancer (TNBC) has the worst prognosis amongst all subtypes. Studies have shown that the achievement of pathologic complete response in the breast and axilla correlates with improved survival. The aim of this study was to identify clinical or pathological features of real-life TNBC patients with a higher risk of early relapse.Materials and methodsSingle-centre retrospective analysis of 127 women with TNBC, stage II–III, submitted to neoadjuvant treatment and surgery between January 2016 and 2020. Multivariate Cox regression analysis for disease free survival (DFS) at 2 years was performed and statistically significant variables were computed into a prognostic model for early relapse.ResultsAfter 29 months of median follow-up, 105 patients (82.7%) were alive and, in total, 38 patients (29.9%) experienced recurrence. The 2-year DFS was 73% (95% CI: 21.3–22.7). In multivariate analysis, being submitted to neoadjuvant radiotherapy [HR 2.8 (95% CI: 1.2–6.4), p = 0.017] and not achieving pathologic complete response [HR 0.3 (95% CI: 0.1–1.7), p = 0.011] were associated with higher risk of recurrence. In our prognostic model, the presence of at least one of these variables defined a subgroup of patients with a worse 2-year DFS than those without these features (59% vs. 90%, p < 0.001, respectively).ConclusionsIn this real-life non-metastatic TNBC cohort, neoadjuvant radiotherapy (performed due to insufficient clinical response to neoadjuvant chemotherapy or significant toxicity) impacted as an independent prognostic factor for relapse along with the absence of pathologic complete response identifying a subgroup of higher risk patients for early relapse that might merit a closer follow-up.  相似文献   
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Polystyrene grafted with a chiral zinc‐complexing camphor‐derived N,N‐disubstituted hydroxyamide is proposed as a new type of functional polymer of high reusability for the development of sustainable organozinc‐catalyzed asymmetric reactions. The main goal of this new functional polymer is the ease of the hydroxyamide‐moiety preparation (cheap chiral ligand obtained straightforwardly from an enantiopure starting material coming from the chiral pool), as well as its chemical robustness when compared with other related zinc‐complexing functional groups. The latter allows the polymer to be active after multiple applications, without significant loss of its catalytic activity. This fact is exemplified by the design and preparation of a polymer functionalized with a bis(hydroxyamide) proved previously as active in the homogeneous enantioselective addition of diethylzinc to aldehydes. The result is a cheap functional polymer with a very high reusability (the enantioselectivity and chemical yield are maintained practically constant after 20 applications). Additionally, a methodology for the multicycle use of these functional polymers is presented. Chirality, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Photosynthetic organisms need copper for cytochrome oxidase and for plastocyanin in the fundamental processes of respiration and photosynthesis. However, excess of free copper is detrimental inside the cells and therefore organisms have developed homeostatic mechanisms to tightly regulate its acquisition, sequestration, and efflux. Herein we show that the CopRS two-component system (also known as Hik31-Rre34) is essential for copper resistance in Synechocystis sp. PCC 6803. It regulates expression of a putative heavy-metal efflux-resistance nodulation and division type copper efflux system (encoded by copBAC) as well as its own expression (in the copMRS operon) in response to the presence of copper in the media. Mutants in this two-component system or the efflux system render cells more sensitive to the presence of copper in the media and accumulate more intracellular copper than the wild type. Furthermore, CopS periplasmic domain is able to bind copper, suggesting that CopS could be able to detect copper directly. Both operons (copMRS and copBAC) are also induced by the photosynthetic inhibitor 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone but this induction requires the presence of copper in the media. The reduced response of two mutant strains to copper, one lacking plastocyanin and a second one impaired in copper transport to the thylakoid, due to the absence of the P(I)-type ATPases PacS and CtaA, suggests that CopS can detect intracellular copper. In addition, a tagged version of CopS with a triple HA epitope localizes to both the plasma and the thylakoid membranes, suggesting that CopS could be involved in copper detection in both the periplasm and the thylakoid lumen.  相似文献   
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