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31.
Tincture of Crataegus (TCR), an alcoholic extract of the berries of hawthorn (Crataegus oxycantha), is used in herbal and homeopathic medicine. The present study was done to investigate the protective effect of TCR on experimentally induced myocardial infarction in rats. Pretreatment of TCR, at a dose of 0.5 mL/100 g bodyweight per day, orally for 30 days, prevented the increase in lipid peroxidation and activity of marker enzymes observed in isoproterenol-induced rats (85 mg kg(-1) s. c. for 2 days at an interval of 24 h). TCR prevented the isoproterenol-induced decrease in antioxidant enzymes in the heart and increased the rate of ADP-stimulated oxygen uptake and respiratory coupling ratio. TCR protected against pathological changes induced by isoproterenol in rat heart. The results show that pretreatment with TCR may be useful in preventing the damage induced by isoproterenol in rat heart. 相似文献
32.
T.?D.?D.?CobleyEmail author D.?A.?T.?Silver V.?S.?Devaraj 《European journal of plastic surgery》2003,26(1):47-49
This contribution introduces an unreported technique of ultrasound-guided steroid injection, for osteoarthritis of the trapeziometacarpal joint. 相似文献
33.
Increased binding of LDL and VLDL to
apo B,E receptors of hepatic plasma membrane of rats treated
with Fibernat 总被引:1,自引:0,他引:1
Summary.
Background:
Research has focussed on the hypocholesterolemic effects
of certain types of dietary fiber such as enhancing conversion
of hepatic cholesterol to bile acids or increase in catabolism
of low density lipoprotein (LDL) via the apo B,E
receptor.
Aim of the
study:
The effect of oral administration of a unique fibre
cocktail of fenugreek seed powder, guar gum and wheat bran
(Fibernat) and its varied effects on some aspects of lipid
metabolism and cholesterol homeostasis in rats were
examined.
Methods:
Rats were administered Fibernat along with the atherogenic
diet containing 1.5 % cholesterol and 0.1 % cholic acid. Amounts
of hepatic lipids, hepatic and fecal bile acids and activity of
hepatic triglyceride lipase (HTGL) were determined. Transmission
electron microscopic examination of the liver tissue and extent
of uptake of
125I-LDL and
125I-VLDL by the hepatic apo B,E
receptor was carried out.
Results:
Food intake and body weight gain were similar between the
3 different dietary groups. Fibernat intake significantly
increased apo B,E receptor expression in rat liver as reflected
by an increase in the maximum binding capacity
(Bmax) of the apo B,E receptor to
125I-LDL and
125I-VLDL. The activity of HTGL was
increased by approximately 1.5-fold in Fibernat-fed rats as
compared to those fed the atherogenic diet alone. A marked
hypocholesterolemic effect was observed. Cholesterol homeostasis
was achieved in Fibernat-fed rats.
Conclusion:
Two possible mechanisms are postulated to be responsible
for the observed hypocholesterolemic effect a) an increase in
conversion of cholesterol to bile acids and b) possibly by
intra-luminal binding which resulted in increased fecal
excretion of bile acids and neutral sterols. The resulting
reduction in cholesterol content of liver cells coupled with
upregulation of hepatic apo B,E receptors and increased
clearance of circulating atherogenic lipoproteins—LDL and very
low density lipoprotein (LDL and VLDL)—is the main mechanism
involved in the hypocholesterolemic effect of Fibernat. The
results suggest that Fibernats effect on plasma LDL
concentration is also possibly mediated by increased
receptor-mediated catabolism of VLDL. Thus, Fibernat therapy is
an effective adjunct to diet therapy and might find potential
use in the therapy of hyperlipidemic subjects. 相似文献
34.
Onur Gilleard David Silver Zeeshan Ahmad Vikram S. Devaraj 《European journal of plastic surgery》2010,33(2):71-74
This paper examines the accuracy of ultrasound (US) in identifying closed flexor tendon ruptures and ruptures following recent
flexor tendon repair. Between January 2001 and December 2006, 80 patients were investigated. Rates of accuracy between clinical
examination and US findings were compared using the Wilcoxon signed ranks test. The chi square test was used to compare differences
in sonographic accuracy according to the nature and zone of injury as well as time elapsed between injury and subsequent US.
The accuracy of US was found to be significantly higher than clinical examination alone (95% vs. 79%, Z = 2.00, p = 0.03). Time between injury and US was the only variable to significantly affect diagnostic accuracy. US findings were 100%
accurate when imaging was undertaken between 1 and 7 days following injury, 88% accurate when undertaken on the same day as
injury and 85.7% accurate when performed after 1 week (X
2 = 6.4, p = 0.04). This retrospective study supports the notion that US can have a valuable role in the management of suspected closed
flexor tendon ruptures and ruptures of recent flexor tendon repairs. 相似文献
35.
36.
BACKGROUND: Subfractions of HDL, particularly large HDL (HDL2), are inversely correlated with the severity of coronary artery disease (CAD). alpha-Tocopherol (AT) is the main lipid-soluble antioxidant in plasma. Results of a previous small study (n = 44) suggested that either a combination of an antioxidant cocktail [800 IU/day 2R,4'R,8'R-(RRR)-AT plus 1 g vitamin C, 25 mg beta-carotene, and 100 microg selenium] or individual antioxidant vitamins combined with simvastatin-niacin (S-N) therapy attenuated the protective increase in HDL2 seen with S-N alone. Few data are available on the effect of AT therapy alone on HDL subfractions, which we addressed in this study. METHODS: In a prospective placebo-controlled study, we randomized 127 patients with stable CAD to receive high-dose RRR-AT (1200 IU/day for 2 years) or placebo. HDL subfractions (small, medium, and large HDL particles) were analyzed by nuclear magnetic resonance spectroscopy. RESULTS: AT concentrations significantly increased in the AT arm but not with placebo. No differences were noted between AT and placebo groups in concentrations of total cholesterol, triglyceride, LDL-cholesterol, or HDL-cholesterol. AT therapy did not affect total, small, medium, or large HDL particles compared with baseline or placebo. Furthermore, serum apolipoprotein A1 concentrations did not change after 2 years AT therapy as compared with baseline. CONCLUSIONS: High-dose AT therapy administered for a 2-year period does not negatively affect either HDL subfractions or apolipoprotein A1 in patients with CAD on statin therapy. Thus the negative interaction previously proposed between antioxidant cocktail and statin therapy cannot be attributed to AT. 相似文献
37.
38.
39.
C-reactive protein decreases endothelial nitric oxide synthase activity via uncoupling 总被引:3,自引:0,他引:3
Singh U Devaraj S Vasquez-Vivar J Jialal I 《Journal of molecular and cellular cardiology》2007,43(6):780-791
C-reactive protein (CRP), a cardiovascular risk marker, induces endothelial dysfunction. We have previously shown that CRP decreases endothelial nitric oxide synthase (eNOS) expression and bioactivity in human aortic endothelial cells (HAECs). In this study, we examined the mechanisms by which CRP decreases eNOS activity in HAECs. To this end, we explored different strategies such as availability of tetrahydrobiopterin (BH4)-a critical cofactor for eNOS, superoxide (O(2)(-)) production resulting in uncoupling of eNOS and phosphorylation/dephosphorylation of eNOS. CRP treatment significantly decreased levels of BH4 thereby promoting eNOS uncoupling. Pretreatment with sepiapterin, a BH4 precursor, prevented CRP-mediated effects on BH(4) levels, superoxide production as well as eNOS activity. The gene expression and enzymatic activity of GTPCH1, the first enzyme in the de novo biosynthesis of BH(4), were significantly inhibited by CRP. Importantly, GTPCH1 is known to be regulated by cAMP-mediated pathway. In the present study, CRP-mediated inhibition of GTPCH1 activity was reversed by pretreatment with cAMP analogues. Furthermore, CRP-induced O(2)(-) production was reversed by pharmacologic inhibition and siRNAs to p47 phox and p22 phox. Additionally, CRP treatment significantly decreased the eNOS dimer: monomer ratio confirming CRP-mediated eNOS uncoupling. The pretreatment of cells with NO synthase inhibitor (N-nitro-l-arginine methyl ester [l-NAME]) also prevented CRP-mediated O(2)(-) production further strengthening CRP-mediated eNOS uncoupling. Additionally, CRP decreased eNOS phosphorylation at Ser1177 as well as increased phosphorylation at Thr495. CRP appears to mediate these effects through the Fcgamma receptors, CD32 and CD64. To conclude, CRP uncouples eNOS resulting in increased superoxide production, decreased NO production and altered eNOS phosphorylation. 相似文献
40.
Beta-catenin can function as an oncogene when it is translocated to the nucleus, binds to T-cell factor (TCF) or lymphoid enhance factor and transactivate its target gene. The mechanism responsible for the activation of Wnt signaling pathway in the Cytotoxin-associated antigen A (CagA) Helicobacter pylori (H. pylori)-infected gastric carcinoma has not been elucidated. We hypothesize that whether interaction of MUC1 with beta-catenin modulates the Wnt signaling and its target gene cyclinD1 in CagA H. pylori-infected gastric carcinoma. The result demonstrate that binding of MUC1 CT with Protein Kinase C delta (PKC delta), tyrosine phosphorylation of MUC1 CT, and CagA are strongly associated with the interaction of MUC1 with beta-catenin in CagA H. pylori-infected gastric carcinoma. A statistically significant difference (chi(2) = 24.49; P < 0.001) was found when the binding of MUC1 CT and beta-catenin was compared to subcellular localization of beta-catenin. We also observed significant statistical correlation (chi(2) = 14.885; P < 0.001) between the cyclinD1 overexpression and the subcellular localization of beta-catenin. The overexpression of cyclinD1 was significantly higher (chi(2) = 13.785; P < 0.002) in advanced gastric carcinoma with CagA H. pylori infection. In addition cyclinD1 overexpression was significantly higher (chi(2) = 37.267; P < 0.001) with the interaction of MUC1 CT with beta-catenin in advanced gastric cancer. These findings indicate that MUC1 CT plays a role in the intracellular signaling through its interaction with beta-catenin and upregulate the Wnt target gene cyclinD1 in CagA H. pylori-infected gastric carcinoma. 相似文献