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Ursolic acid (1), a triterpenoid with pleotropic effects including inhibition of tumor growth, is well known to trigger apoptosis of nucleated cells. The effect is at least partially due to altered gene expression and mitochondrial dysfunction. Erythrocytes lack nuclei and mitochondria but, similar to nucleated cells, may undergo suicidal cell death or eryptosis, which is characterized by cell shrinkage and phospholipid scrambling of the cell membrane. Triggers of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i), ceramide formation and/or ATP depletion. The present study has investigated whether or not 1 induces eryptosis. [Ca2+]i was estimated from Fluo-3 fluorescence, cell volume from forward scatter, phospholipid scrambling from annexin V binding, hemolysis from hemoglobin release, and cytosolic ATP concentration ([ATP]i) utilizing a luciferase assay and ceramide-utilizing fluorescent antibodies in FACS analysis. As a result, exposure of erythrocytes for 48 h to 1 (≥5 μM) did not significantly modify [ATP]i, but significantly increased [Ca2+]i, stimulated ceramide formation, decreased forward scatter, triggered annexin V binding, and elicited hemolysis. At 5 μM, 1 stimulated phospholipid scrambling in 10% and hemolysis in 2% of treated erythrocytes. Annexin V binding was blunted in the nominal absence of Ca2+. In conclusion, the food component ursolic acid stimulates suicidal death of erythrocytes, i.e., cells devoid of nuclei and mitochondria.  相似文献   
514.
Rationale:Human myiasis is the invasion of tissue or organs by fly larvae.This could be obligatory,facultative,or accidental.Patient concerns:A 4-year-old Saudi...  相似文献   
515.
ABSTRACT: OBJECTIVE: Sagittal abdominal diameter (SAD) is a novel anthropometric measure hypothesized to be a surrogate measure of visceral abdominal obesity in adults. This study aims to determine whether SAD is superior to other anthropometric measures such as body mass index (BMI) and waist to hip ratio (WHR) in terms of association to cardiometabolic risk and circulating adipocytokine concentrations in a cohort of Saudi children and adolescents. METHODS: A total of 948 (495 boys and 453 girls) apparently healthy children with varying BMI, aged 10-17 years, were included in this cross sectional study. Fasting glucose, lipid profile, leptin, adiponectin, resistin, insulin, TNF-alpha and aPAI-1 were measured in serum and HOMA-IR was calculated. MetS components were defined according to the International Diabetes Federation (IDF) criteria. RESULTS: BMI was superior to SAD as well as WHR, and had the highest number of significant associations to MetS components and adipocytokines even after adjustment for age and gender, including blood pressure, lipids, glucose and leptin. CONCLUSION: In conclusion, while SAD is significantly associated with components of MetS among children and adolescents, it is not superior to BMI. The use of SAD therefore may not be practical for use in the pediatric clinical setting. Follow-up studies are needed to determine whether SAD has clinical significance in terms of harder outcomes such as predicting diabetes mellitus or cardiovascular diseases.  相似文献   
516.
Purpose: To report a patient with transient acute generalized thrombotic thrombocytopenic purpura (TTP) who suffered severe permanent visual loss due to retinal vascular occlusions in both eyes. Methods: Case report. Results: Severe permanent visual loss occurred in a patient with acute transient TTP. Extensive soft exudates were seen at the fundus of both eyes. Fluorescein angiography demonstrated multiple retinal vascular occlusions associated with capillary nonperfusion. Conclusions: Severe and permanent visual loss due to retinal vascular occlusions demonstrated by fluorescein angiography occurred in a patient with transient thrombotic thrombocytopenic purpura.  相似文献   
517.
Recently, both living and deceased organ donation rates have hit a plateau, despite increases in need for viable organs. One approach to improve donation rate is public education and policy; thus, it is necessary to understand the information the public is receiving regarding organ donation. We hypothesized that primetime medical dramas portray organ donation and transplantation in a negative manner. We compiled data on all primetime medical drama episodes with transplant themes from November 2008 through June 2010 and assessed depictions of organ donors and transplant candidates. Positive and negative thematic elements surrounding the process and individuals involved were also identified. One hundred and fifty-five million and 145 million households watched episodes containing any negative message and any positive message, respectively. Episodes containing only negative messages had over twice the household viewership per episode compared to episodes containing only positive messages (8.4 million vs. 4.1 million, p = 0.01). Widespread exposure to these representations may reinforce public misconceptions of transplantation. The transplant community should consider the popularity of medical dramas as an opportunity to impact the perception of organ donation and transplantation for millions of Americans.  相似文献   
518.
Several matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have been implicated in the development and outcome of coronary artery disease (CAD). We investigated whether MMP-12 and TIMP-1 levels were associated with risk, severity, and outcome of CAD. Plasma MMP-12 and TIMP-1 levels are measured in 50 and 44 patients with CAD, respectively, by enzyme-linked immunosorbent assay. Of all patients, 16 were taking statins. Patients who were not on statins were classified into 3 groups according to number of >50% stenotic vessels. Compared with 29 volunteers without CAD, patients without statins (n = 34) had higher MMP-12 concentrations (1.71 vs 1.08 ng/ml, p = 0.021). MMP-12 levels were significantly lower in patients with than in those without statin treatment (0.99 vs 1.71 ng/ml, p = 0.008). There was no association between MMP-12 levels and number of >50% stenotic vessels. MMP-12 concentrations were not associated with outcome of CAD. However, plasma TIMP-1 levels were associated with restenosis independently of number of stenotic vessels and age (p = 0.035) but not with risk or severity of CAD. In conclusion, plasma MMP-12 concentration was associated with the presence of CAD. Statin therapy decreases plasma MMP-12 levels in patients with CAD. Increased TIMP-1 levels may prevent restenosis after angioplasty.  相似文献   
519.
The current study focuses on the development and evaluation of nano lipidic carriers (NLCs) for codelivery of sorafenib (SRF) and ganoderic acid (GA) therapy in order to treat hepatocellular carcinoma (HCC). The dual drug-loaded NLCs were prepared by hot microemulsion technique, where SRF and GA as the drugs, Precirol ATO5, Capmul PG8 as the lipids, while Solutol HS15 and ethanol was used as surfactant and cosolvents. The optimized drug-loaded NLCs were extensively characterized through in vitro and in vivo studies. The optimized formulation had particle size 29.28 nm, entrapment efficiency 93.1%, and loading capacity 14.21%. In vitro drug release studies revealed>64% of the drug was released in the first 6 h. The enzymatic stability analysis revealed stable nature of NLCs in various gastric pH, while accelerated stability analysis at 25C/60% RH indicated the insignificant effect of studied condition on particle size, entrapment efficiency, and loading capacity of NLCs. The cytotoxicity performed on HepG2 cells indicated higher cytotoxicity of SRF and GA-loaded NLCs as compared to the free drugs (p < 0.05). Furthermore, the optimized formulation suppressed the development of hepatic nodules in the Wistar rats and significantly reduced the levels of hepatic enzymes and nonhepatic elements against DEN intoxication. The SRF and GA-loaded NLCs also showed a significant effect in suppressing the tumor growth and inflammatory cytokines in the experimental study. Further, histopathology study of rats treated SRF and GA-loaded NLCs and DEN showed absence of necrosis, apoptosis, and disorganized hepatic parenchyma, etc. over other treated groups of rats. Overall, the dual drug-loaded NLCs outperformed over the plain drugs in terms of chemoprotection, implying superior therapeutic action and most significantly eliminating the hepatic toxicity induced by DEN in Wistar rat model.  相似文献   
520.
Intravenous infusion of recombinant human activated Factor VII (FVIIa) has been used for over a decade in the successful management of bleeding episodes in patients with inhibitory antibodies to Factor VIII or Factor IX. Previously, we showed that expression of murine FVIIa (mFVIIa) from an adeno-associated viral (AAV) vector corrected abnormal hemostatic parameters in hemophilia B mice. To pursue this as a therapeutic approach, we sought to define safe and effective levels of FVIIa for continuous expression. In mice transgenic for mFVIIa or injected with AAV-mFVIIa, we analyzed survival, expression levels, in vitro and in vivo coagulation tests, and histopathology for up to 16 months after birth/mFVIIa expression. We found that continuous expression of mFVIIa at levels at or below 1.5 microg/ml was safe, effective, and compatible with a normal lifespan. However, expression levels of 2 microg/ml or higher were associated with thrombosis and early mortality, with pathologic findings in the heart and lungs that were rescued in a low-factor X (low-FX) mouse background, suggesting a FX-mediated effect. The findings from these mouse models of continuous FVIIa expression have implications for the development of a safe gene transfer approach for hemophilia and are consistent with the possibility of thromboembolic risk of continuously elevated FVIIa levels.  相似文献   
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