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1.
The activity of a phosphatase was characterized in intact mycelial forms of Fonsecaea pedrosoi, a pathogenic fungus that causes chromoblastomycosis. At pH 5.5, this fungus hydrolyzed p-nitrophenylphosphate (p-NPP) to p-nitrophenol (p-NP) at a rate of 12.78 +/- 0.53 nmol p-NP per h per mg hyphal dry weight. The values of Vmax and apparent Km for p-NPP hydrolyses were measured as 17.89 +/- 0.92 nmol p-NP per h per mg hyphal dry weight and 1.57 +/- 0.26 mmol/l, respectively. This activity was inhibited at increased pH, a finding compatible with an acid phosphatase. The enzymatic activity was strongly inhibited by classical inhibitors of acid phosphatases such as sodium orthovanadate (Ki = 4.23 micromol/l), sodium molybdate (Ki = 7.53 micromol/l) and sodium fluoride (Ki = 126.78 micromol/l) in a dose-dependent manner. Levamizole (1 mmol/l) and sodium tartrate (10 mmol/l), had no effect on the enzyme activity. Cytochemical localization of the acid phosphatase showed electrondense cerium phosphate deposits on the cell wall, as visualized by transmission electron microscopy. Phosphatase activity in F. pedrosoi seems to be associated with parasitism, as sclerotic cells, which are the fungal forms mainly detected in chromoblastomycosis lesions, showed much higher activities than conidia and mycelia did. A strain of F. pedrosoi recently isolated from a human case of chromoblastomycosis also showed increased enzyme activity, suggesting that the expression of surface phosphatases may be stimulated by interaction with the host.  相似文献   
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An assessment of a non-invasive technique for measurement of stroke distance was made using a portable Doppler ultrasound machine. The aim was to determine the measurement error of repeated stroke distance measurements (Within-observer variability) and to assess measurement agreement between two operators (between-observer variability). The measurement error (within-observer variability) for both operators was similar at approximately 2 cm. However, the measurements of the two operators (between-observer variability) did not agree well. Using the mean (SD) of three readings by each operator, the mean difference between the operators was -0.21 cm (1.96) giving a 95% confidence interval for the differences of -4.0 to +3.6 cm. There were significant positive and negative correlations between stroke distance and a variety of variables (age, height, weight, heart rate), but the relations were weak. The results indicate that the Doppler ultrasound technique for measurement of stroke distance would best be used to study trend changes in an individual patient, or subject, by a single operator.  相似文献   
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There is substantial evidence documenting the effects of behavioural interventions on weight loss (WL). However, behavioural approaches to initial WL are followed by some degree of longer-term weight regain, and large trials focusing on evidence-based approaches to weight loss maintenance (WLM) have generally only demonstrated small beneficial effects. The current state-of-the-art in behavioural interventions for WL and WLM raises questions of (i) how we define the relationship between WL and WLM, (ii) how energy balance (EB) systems respond to WL and influence behaviours that primarily drive weight regain, (iii) how intervention content, mode of delivery and intensity should be targeted to keep weight off, (iv) which mechanisms of action in complex interventions may prevent weight regain and (v) how to design studies and interventions to maximise effective longer-term weight management. In considering these issues a writing team within the NoHoW Consortium was convened to elaborate a position statement, and behaviour change and obesity experts were invited to discuss these positions and to refine them. At present the evidence suggests that developing the skills to self-manage EB behaviours leads to more effective WLM. However, the effects of behaviour change interventions for WL and WLM are still relatively modest and our understanding of the factors that disrupt and undermine self-management of eating and physical activity is limited. These factors include physiological resistance to weight loss, gradual compensatory changes in eating and physical activity and reactive processes related to stress, emotions, rewards and desires that meet psychological needs. Better matching of evidence-based intervention content to quantitatively tracked EB behaviours and the specific needs of individuals may improve outcomes. Improving objective longitudinal tracking of energy intake and energy expenditure over time would provide a quantitative framework in which to understand the dynamics of behaviour change, mechanisms of action of behaviour change interventions and user engagement with intervention components to potentially improve weight management intervention design and evaluation.  相似文献   
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BackgroundThe incidence of myocardial injury (MI) in patients with COVID-19 in Brazil and the prognostic impact of MI have not been elucidated.ObjectivesTo describe the incidence of MI in patients with COVID-19 in the intensive care unit (ICU) and to identify variables associated with its occurrence. The secondary objective was to assess high-sensitivity troponin I as a predictor of in-hospital mortality.MethodsRetrospective, observational study conducted between March and April 2020 with cases of confirmed COVID-19 admitted to the ICU. Numerical variables were compared by using Student t test or Mann-Whitney U test. The chi-square test was used for categorical variables. Multivariate analysis was performed with variables associated with MI and p<0.2 to determine predictors of MI. The ROC curve was used to determine the troponin value capable of predicting higher in-hospital mortality. Survival functions were estimated by use of the Kaplan-Meier method from the cut-off point indicated in the ROC curve.ResultsThis study assessed 61 patients (63.9% of the male sex, mean age of 66.1±15.5 years). Myocardial injury was present in 36% of the patients. Systemic arterial hypertension (HAS) [OR 1.198; 95%CI: 2.246-37.665] and body mass index (BMI) [OR 1.143; 95%CI: 1.013-1.289] were independent risk predictors. High-sensitivity troponin I >48.3 ng/mL, which was determined in the ROC curve, predicts higher in-hospital mortality [AUC 0.786; p<0.05]. Survival in the group with high-sensitivity troponin I >48.3 ng/mL was lower than that in the group with values ≤48.3 ng/dL [20.3 x 43.5 days, respectively; p<0.05].ConclusionThere was a high incidence of MI in severe COVID-19 with impact on higher in-hospital mortality. The independent risk predictors of MI were SAH and BMI. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)  相似文献   
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Obesity‐induced insulin resistance and type 2 diabetes mellitus can ultimately result in various complications, including diabetic cardiomyopathy. In this case, cardiac dysfunction is characterized by metabolic disturbances such as impaired glucose oxidation and an increased reliance on fatty acid (FA) oxidation. Mitochondrial dysfunction has often been associated with the altered metabolic function in the diabetic heart, and may result from FA‐induced lipotoxicity and uncoupling of oxidative phosphorylation. In this review, we address the metabolic changes in the diabetic heart, focusing on the loss of metabolic flexibility and cardiac mitochondrial function. We consider the alterations observed in mitochondrial substrate utilization, bioenergetics and dynamics, and highlight new areas of research which may improve our understanding of the cause and effect of cardiac mitochondrial dysfunction in diabetes. Finally, we explore how lifestyle (nutrition and exercise) and pharmacological interventions can prevent and treat metabolic and mitochondrial dysfunction in diabetes.  相似文献   
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The immune system of neonates has been considered functionally immature, and due to their high susceptibility to infections, the aim of this study was to analyse the phenotypic differences in leucocyte populations in healthy preterm and full‐term newborns. We evaluated the absolute numbers and frequencies of dendritic cells (DCs) and DC subsets, monocytes and T and B lymphocytes and subsets in the cord blood of healthy moderate and very preterm (Group 1), late preterm (Group 2) and full‐term (Group 3) newborns and in healthy adults, as controls, by flow cytometry. The analyses revealed statistically higher absolute cell numbers in neonates compared with adults due to the characteristic leucocytosis of neonates. We observed a lower frequency of CD80+ myeloid and plasmacytoid DCs in Group 1 and reduced expression of TLR‐4 on myeloid DCs in all neonates compared with adults. TLR‐2+ monocytes were reduced in Group 1 compared with Groups 2 and 3, and TLR‐4+ monocytes were reduced in Groups 1 and 2 compared with Group 3. The frequencies and numbers of naïve CD4+ T and CD19+ B cells were higher in the three groups of neonates compared with adults, while CD4+ effector and effector memory T cells and CD19+ memory B cells were elevated in adults compared with neonates, as expected. Our study provides reference values for leucocytes in cord blood from term and preterm newborns, which may facilitate the identification of immunological deficiencies in protection against extracellular pathogens.  相似文献   
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Wright  DG; Kenney  RF; Oette  DH; LaRussa  VF; Boxer  LA; Malech  HL 《Blood》1994,84(4):1257-1267
Recombinant human granulocyte colony-stimulating factor (G-CSF) treatment has been shown to increase average neutrophil counts substantially in patients with childhood-onset cyclic neutropenia (or "cyclic hematopoiesis"), but not to eliminate the cyclic oscillations of neutrophil counts or those of other blood elements (monocytes, platelets, eosinophils, and reticulocytes) that are characteristic of this hematopoietic disorder. Indeed, oscillations of neutrophil counts are amplified during G-CSF treatment. We have compared the effects of recombinant granulocyte-macrophage-CSF (GM-CSF) with those of G-CSF in three patients with this disease (2 men and 1 woman, 17, 30, and 32 years of age). These patients were treated with GM-CSF (2.1 micrograms/kg/day, subcutaneously) for 6 weeks, preceded and followed by 6 to 13 weeks of detailed observation to document changes in the cyclic oscillations of blood neutrophils and other blood elements; two of the patients were subsequently treated with G-CSF (5.0 micrograms/kg/d, subcutaneously) and observed for comparable periods of time. Unlike G-CSF treatment, which increased average neutrophil counts more than 20-fold, GM-CSF increased neutrophil counts only modestly, from 1.6- to 3.9-fold, although eosinophilia of varying prominence was induced in each patient. However, at the same time, GM-CSF treatment dampened or eliminated the multilineage oscillations of circulating blood elements (neutrophils, monocytes, platelets, and/or reticulocytes) in each of the patients. In contrast, G-CSF treatment of the same patients markedly amplified the oscillations of neutrophil counts and caused the cycling of other blood elements (monocytes in particular) to become more distinct. These findings support the conclusion that the distinctive cycling of blood cell production in childhood-onset cyclic neutropenia results from abnormalities in the coordinate regulation of both GM-CSF-responsive, multipotential progenitor cells and G-CSF-responsive, lineage-restricted, neutrophil progenitors.  相似文献   
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