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471.
Schizophyllum commune (n = 30) showed lowest geometric mean MICs of isavuconazole (0.19 μg/ml), itraconazole (0.2 μg/ml), voriconazole (0.24 μg/ml), and amphotericin B (0.29 μg/ml) and high geometric mean MICs of fluconazole (19.39 μg/ml) and flucytosine (17.28 μg/ml). Five cases (of 8) of allergic bronchopulmonary mycosis that were treated with itraconazole had no recrudescence after 6 to 24 months of follow-up. One case each of invasive pulmonary mycosis and fungal ball were treated successfully with voriconazole and itraconazole.  相似文献   
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473.
Acute appendicitis is a clinical diagnosis, so it’s impossible to have a definitive diagnosis by gold standard (histopathology) pre operatively. The treatment being surgical, negative appendicectomy rates are high. Present study was conducted to evaluate Alvarado scoring system for diagnosis of acute appendicitis and its co relation by histopathology. Retrospective study of consecutive patients admitted with suspected acute appendicitis during the period March 2005 to March 2007. The Alvarado scoring system was computed from admission notes and records and correlated with the histopathology reports. Out of 155 patients, 92 underwent appendicectomy with the intention to treat appendicitis and diagnosis was confirmed in 80 patients. Reliability of scoring system was assessed by calculating negative appendicectomy rate and positive predictive value. The normal appendicectomy frequency was 13% and positive predictive value was 86%. Alvarado scoring system is easy, simple, cheap, useful tool in pre operative diagnosis of acute appendicitis and can work effectively in routine practice.  相似文献   
474.

Background  

Viral hepatitis is a serious global public health problem affecting billions of people globally, and both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are rapidly spreading in the developing countries including Bangladesh due to the lack of health education, poverty, illiteracy and lack of hepatitis B vaccination. Also there is lack of information on their prevalence among the general population. So, a population-based serological survey was conducted in Dhaka to determine the prevalence and risk factors of HBV and HCV infections.  相似文献   
475.
We reported previously that bone morphogenetic protein 7 (BMP7) could induce epithelial-mesenchymal transition (EMT) in PC-3 prostate cancer cells grown in tissue culture plates. In this study, we examined BMP7-induced morphological and molecular expression changes that are characteristic of EMT using these cells under both two- (2D) and three-dimensional (3D) culture conditions. Filamentous outgrowths from spheroid structures that were formed from PC-3 cells in 3D cultures were strikingly evident when the spheroids were exposed to extracellular BMP7. This morphological change in 3D was accompanied by down-regulation of E-cadherin, which is an essential adhesion molecule for the integrity of epithelial phenotype. Invasiveness of the cancer cells was significantly enhanced with BMP7 treatment along with activation and up-regulation of proteases such as MMP1, MMP13, and urokinase plasminogen activator. Signal transduction of EMT conversion was examined by the use of certain pathway-specific inhibitors. Of the chemical inhibitors tested, inhibitors of PI3 kinase and Erk were found to suppress BMP-induced morphological changes both in 2D and 3D conditions. These results suggest that, besides the Smad signaling pathways, BMP-induced activation of PI3K and Erk contribute to EMT morphologic conversion of the PC-3 prostate cancer cells. Together, the results support the notion that the complexity of EMT may be better evaluated in terms of both spatial and temporal processes in 3D cell culture models that are physiologically more relevant than the cell growth in tissue culture plates.  相似文献   
476.
The synthesis of a light-sensitive polyurethane-based composite material (PUX-NO) is described. In its polyurethane medium, PUX-NO contains entrapped silica xerogel particles in which a photoactive manganese nitrosyl has been incorporated. Green flexible films of PUX-NO readily release nitric oxide (NO) only when exposed to low power (mW) visible light. Incorporation of the nitrosyl in the xerogel not only retains the nitrosyl (NO donor) within the composite material but also provides the right extent of hydration. Pre-swelled films of PUX-NO have water content close to 30 Wt % and such films can be stored for months under slightly moist condition without loss in NO-delivering capacity. The NO-releasing parameters of the film have been determined. The NO-releasing capacity of PUX-NO films can be conveniently altered by changing the amount of the nitrosyl as well as the thickness of the films. Patches of PUX-NO film have been successfully employed to reduce drastically bacterial loads of both gram-positive and gram-negative bacteria including methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii under the total control of light. Effective control of infections by these bacterial pathogens via delivery of proper doses of NO only to the sites of infection appears feasible with PUX-NO films.  相似文献   
477.

Aim:

The mechanism of action of Annona squamosa hexane extract in mediating antihyperglycemic and antitriglyceridimic effect were investigated in this study.

Materials and Methods:

The effects of extract on glucose uptake, insulin receptor-β (IR-β), insulin receptor substrate-1 (IRS-1) phosphorylation and glucose transporter type 4 (GLUT4) and phosphoinositide 3-kinase (PI3 kinase) mRNA expression were studied in L6 myotubes. The in vitro mechanism of action was tested in protein-tyrosine phosphatase 1B (PTP1B), G-protein-coupled receptor 40 (GPR40), silent mating type information regulation 2 homolog 1 (SIRT1) and dipeptidyl peptidase-IV (DPP-IV) assays. The in vivo efficacy was characterized in ob/ob mice after an oral administration of the extract for 21 days.

Results:

The effect of extract promoted glucose uptake, IR-β and IRS-1 phosphorylation and GLUT4 and PI3 kinase mRNA upregulation in L6 myotubes. The extract inhibited PTP1B with an IC50 17.4 μg/ml and did not modulate GPR40, SIRT1 or DPP-IV activities. An oral administration of extract in ob/ob mice for 21 days improved random blood glucose, triglyceride and oral glucose tolerance. Further, the extract did not result in body weight gain before and after treatment (29.3 vs. 33.6 g) compared to rosiglitazone where significant body weight gain was observed (28.4 vs. 44.5 g; *P<0.05 after treatment compared to before treatment).

Conclusion:

The results suggest that Annona squamosa hexane extract exerts its action by modulating insulin signaling through inhibition of PTP1B.KEY WORDS: Annona squamosa, type 2 diabetes mellitus, insulin mimetics, PTP1B inhibitor, OGTT, ob/ob mice  相似文献   
478.
479.
The mechanism(s) underlying cardiac reparative effects of bone marrow-derived mesenchymal stem cells (MSC) remain highly controversial. Here we tested the hypothesis that MSCs regenerate chronically infarcted myocardium through mechanisms comprising long-term engraftment and trilineage differentiation. Twelve weeks after myocardial infarction, female swine received catheter-based transendocardial injections of either placebo (n = 4) or male allogeneic MSCs (200 million; n = 6). Animals underwent serial cardiac magnetic resonance imaging, and in vivo cell fate was determined by co-localization of Y-chromosome (Ypos) cells with markers of cardiac, vascular muscle, and endothelial lineages. MSCs engrafted in infarct and border zones and differentiated into cardiomyocytes as ascertained by co-localization with GATA-4, Nkx2.5, and α-sarcomeric actin. In addition, Ypos MSCs exhibited vascular smooth muscle and endothelial cell differentiation, contributing to large and small vessel formation. Infarct size was reduced from 19.3 ± 1.7% to 13.9 ± 2.0% (P < 0.001), and ejection fraction (EF) increased from 35.0 ± 1.7% to 41.3 ± 2.7% (P < 0.05) in MSC but not placebo pigs over 12 weeks. This was accompanied by increases in regional contractility and myocardial blood flow (MBF), particularly in the infarct border zone. Importantly, MSC engraftment correlated with functional recovery in contractility (R = 0.85, P < 0.05) and MBF (R = 0.76, P < 0.01). Together these findings demonstrate long-term MSC survival, engraftment, and trilineage differentiation following transplantation into chronically scarred myocardium. MSCs are an adult stem cell with the capacity for cardiomyogenesis and vasculogenesis which contribute, at least in part, to their ability to repair chronically scarred myocardium.  相似文献   
480.
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