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891.
The extracts of red yeast rice (RYR) are currently the most effective cholesterol-lowering nutraceuticals. This activity is mainly due to monacolin K, a weak reversible inhibitor of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, whose daily consumption causes a reduction in low-density lipoprotein (LDL)-cholesterol plasma levels up to 15% to 25% within 6 to 8 weeks. The decrease in LDL-cholesterol is accompanied by a proportional decrease in total and non–high-density lipoprotein cholesterol, plasma apolipoprotein B, and high-sensitivity C-reactive protein. Some trials suggest that RYR use is associated with improvement in endothelial function and arterial stiffness, whereas a long-term study supports its role in the prevention of cardiovascular events. Despite the statin-like mechanism of action, the risk related to 3 to 10 mg monacolin K taken per day is minimal (mild myalgia in previously severely statin-intolerant subjects). RYR could represent a therapeutic tool to support lifestyle improvement in managing mild to moderate hypercholesterolemia in low-risk patients, including those who cannot be treated with statins or other LDL-cholesterol–lowering therapies.  相似文献   
892.
AIM: Accumulating evidence suggests that combination therapy using oral antidiabetic agents with different mechanisms of action may be highly effective in achieving and maintaining target blood glucose levels. The aim of our study is to evaluate the differential effect on glucose and lipid parameters of the association between glimepiride plus metformin and rosiglitazone plus metformin in patients affected by type 2 diabetes and metabolic syndrome. METHODS: Patients were enroled, evaluated and followed at two Italian centres. We evaluated 99 type 2 diabetic patients with metabolic syndrome (48 males and 47 females; 23 males and 24 females, aged 52 +/- 5 with glimepiride; 25 males and 23 females, aged 54 +/- 4 with cglitazone). All were required to have been diagnosed as being diabetic for at least 6 months and did not have glycaemic control with diet and oral hypoglycaemic agents such as sulphonylureas or metformin, both to the maximum tolerated dose. All patients took a fixed dose of metformin, 1500 mg/day. We administered glimepiride (2 mg/day) or rosiglitazone (4 mg/day) in a randomized, controlled, double-blind clinical study. We evaluated body mass index (BMI), glycaemic control, lipid profile [total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol and triglycerides] and lipoprotein parameters [apolipoprotein A-I and apolipoprotein B (Apo B)] during 12 months of this treatment. RESULTS: A total of 95 patients completed the study. Significant BMI decrease was observed at 12 months in glimepiride and rosiglitazone group (p < 0.05 and p < 0.01 respectively) as well as of glycated haemoglobin decrease (p < 0.05 and p < 0.01 respectively), mean fasting plasma glucose and postprandial plasma glucose levels (p < 0.05 and p < 0.01 respectively). A decrease in fasting plasma insulin and postprandial plasma insulin at 12 months (p < 0.05 and p < 0.01 respectively) compared with the baseline value in rosiglitazone group was observed. Furthermore, homeostasis model assessment index improvement was obtained only at 9 and 12 months (p < 0.05 and p < 0.01 respectively) compared with the baseline value in rosiglitazone group. Significant TC, LDL-C and Apo B improvement (p < 0.05 respectively) was present in glimepiride group after 12 months compared with the baseline values, and these variations were significant (p < 0.05) between groups. Of the 95 patients who completed the study, 8.5% of patients in glimepiride group and 12.5% of patients in rosiglitazone group had side-effects (p = not significant). Four patients had transient side-effects in glimepiride group and six patients in rosiglitazone group. Altogether, we did not have statistically significant changes in transaminases. CONCLUSIONS: The rosiglitazone-metformin association significantly improve the long-term control of all insulin-resistance-related parameters in comparison with the glimepiride-metformin-treated group. On the other side, glimepiride treatment is associated to a slight improvement in cholesterolaemia, not observed in the rosiglitazone-treated patients.  相似文献   
893.
We hypothesized that matrix metalloproteinase (MMP)-2, -9, and tissue inhibitor metalloproteinase-1, -2 (TIMP-1, -2) would be abnormal in diabetes and in acute coronary syndromes (ACS). We measured MMP-2, -9, and TIMP-1, -2 plasma levels in healthy subjects (controls), in type 2 diabetic patients, in nondiabetic patients with ACS (ACS) and in diabetic patients with ACS (DACS). We enrolled 165 controls, 181 diabetic patients, 78 ACS, and 46 DACS. We measured also BMI (body mass index), HbA1c (glycated hemoglobin) FPG (fasting plasma glucosa), FPI (fasting plasma insulin), HOMA index (homeostasis model assessment index), SBP (systolic blood pressure), DBP (diastolic blood pressure), TC (total cholesterol), LDL-C (low density lipoprotein cholesterol), HDL-C (high-density lipoprotein cholesterol), Tg (triglycerides), Lp(a) (lipoprotein(a)) PAI-1 (plasminogen activator inhibitor-1), Hct (homocysteine), Fg (fibrinogen), and hs-CRP (high-sensitivity C-reactive protein). A significant increase of BMI was observed in the diabetic group, in ACS and DACS patients compared to controls. A significant increase of SBP and DBP resulted in the diabetic and DACS groups, while only SBP improvement was present in ACS patients with respect to controls. A decrease in SBP and DBP was observed in the ACS group, while SBP variation was present in DACS patients compared to diabetics, and DBP increase was obtained in the DACS group with respect to ACS patients. TC, LDL-C, Tg, and Lp(a) increase was present in diabetics, while TC, Tg, and Lp(a) improvement was present in ACS and DACS patients with a significant decrease of HDL-C levels in diabetic, ACS, and DACS groups compared to controls. A decrease in LDL-C was obtained in ACS and DACS groups, while HDL-C increase was observed in these patients with respect to diabetics. Tg levels were higher in the DACS group compared to diabetics and ACS patients, respectively. Increases in PAI-1, Hct, Fg, and hs-CRP were present in diabetic and DACS groups, while PAI-1, Hct, and hs-CRP improvement was obtained in ACS patients with respect to controls. Higher PAI-1 levels came about in ACS and DACS groups, while HCT and Fg levels were lower in ACS patients compared to diabetics. An increase in Fg was present in the DACS group with respect to ACS patients. A decrease in Hs-CRP was observed in DACS patients compared to diabetics and the ACS group, respectively. Higher MMP-2, MMP-9, TIMP-1, and TIMP-2 levels were present in diabetic, ACS, and DACS patients compared to controls. Significant MMP-2, TIMP-1, and TIMP-2 increases were observed in ACS and DACS groups, while MMP-9 decreased in these patients compared to diabetics. In conclusion, MMP-2, MMP-9, TIMP-1, and TIMP-2 plasma levels were higher in diabetic, ACS, and DACS patients, which may reflect abnormal extracellular matrix metabolism in diabetes and in acute coronary syndrome.  相似文献   
894.
Our aim in this study was to evaluate the relationship between metabolic syndrome (MS) as defined by different criteria and the severity of coronary lesions in a sample of diabetic and non-diabetic patients undergoing elective coronary angiography. All patients had blood and urine tests, physical examinations were performed before angiography, and finally they were classified based on three criteria (World Health Organisation-WHO, Adult Treatment Panel-ATP III and International Diabetes Federation-IDF). Eighty-eight patients were diabetic, and 96 patients were non-diabetic. Among all patients, diabetics had significantly higher Gensini scores (P < 0.001). According to WHO criteria (P = 0.005) and IDF criteria (P = 0.015) metabolic syndrome patients had higher Gensini scores, but for ATP III criteria difference was not significant. When we evaluated diabetics and non-diabetics separately, non-diabetic patients with MS had significantly higher scores with WHO definition (P = 0.015) and mildly higher but not significant values with other MS criteria (P = 0.057 for both IDF and ATP III). Neither any one of MS components nor gender revealed significant relationship with coronary disease severity. In our study with a cohort of Turkish patients undergoing elective coronary angiography; we concluded that MS should be taken into consideration, especially in non-diabetic patients.  相似文献   
895.
Ultrastructural analysis of human natural killer cell activation   总被引:3,自引:0,他引:3  
In this study we describe characteristic ultrastructural changes of CD3- large granular lymphocytes (LGL), ie, natural killer (NK) cells, following stimulation with recombinant (r) interleukin 2 (IL 2) or r- gamma interferon (r-gamma IFN) and after interaction with K562 target cells (TC) or Sepharose-bound anti-Fc gamma receptor (FcR) monoclonal antibody (MoAb). When compared to resting cells the cytolytic activity of r-IL 2- and r-gamma IFN-stimulated cells against K562 TC was enhanced. The r-IL 2-stimulated LGL were larger and consistently displayed the shape and cytoskeletal rearrangement characteristic of activated cells. The Golgi apparatus was expanded, and the number of electron-dense granules and vesicles was increased. The ultrastructural changes in r-gamma IFN-stimulated LGL were markedly different from those observed following r-IL 2 activation. Cells did not exhibit changes in size, shape, cytoskeletal organization, or in the structure of the Golgi apparatus. However, r-gamma IFN-stimulated cells exhibited distinctive changes in the structure and content of electron-dense granules with deaggregation of the matrix and parallel tubular arrays (PTAs). Within organelles apparently derived from the electron-dense granules, vesicular and tubular structures were noted that may be the morphological equivalent of cytotoxic factors produced by cytolytic effector cells. These ultrastructural observations indicate that r-IL 2 and r-gamma IFN enhance the lytic ability of NK cells by acting on distinct cell machineries. The cytolytic ability was decreased when LGL were pretreated with K562 TC or immobilized anti-FcR antibody. In both experimental conditions cells displayed ultrastructural features indicating activation as well as loss of cytoplasmic granules and other Golgi-derived organelles. Stimulation of r-gamma IFN- or r-IL 2- activated LGL with K562 TC or Sepharose-bound anti-FcR antibody decreased their cytolytic ability, with cells depleted of granules at the ultrastructural level. Intracytoplasmic fusion of granules and a massive release of the granule content were found in r-IL 2-stimulated cells, reminiscent of the mechanism of basophil degranulation. These observations suggest that multiple activation signals involving distinct surface membrane molecules induce release of cytolytic factors by both resting and activated NK cells.  相似文献   
896.
Emeis  JJ; Hoekzema  R; de Vos  AF 《Blood》1995,85(1):115-120
In experimental animals and humans, intravenous (i.v.) injection of endotoxin induces large increases in circulating plasminogen activator inhibitor type-1 (PAI-1), a major inhibitor of blood fibrinolysis. A similar increase is seen after the injection of interleukin-1 (IL-1) or of tumor necrosis factor-alpha (TNF-alpha), suggesting that these cytokines mediate the induction, by endotoxin, of PAI-1. To test this hypothesis we pretreated rats, before i.v. endotoxin, with compounds that inhibit the formation of cytokines (pentoxifylline; dexamethasone), or with compounds that inhibit the action of these cytokines (anti-TNF antiserum for TNF-alpha; IL-1 receptor antagonist for IL-1). None of these pretreatments affected the induction of PAI-1 synthesis by endotoxin. However, pretreatment did reduce the endotoxin- induced increase in plasma tPA antigen concentration. Thus, the data suggest that, in rats in vivo, TNF-alpha and IL-1 are not significantly involved in the induction of PAI-1 by endotoxin.  相似文献   
897.
INTRODUCTION: Management of atrial tachyarrhythmias represents a significant challenge in patients with implantable cardioverter defibrillators (ICDs). Drug therapy of these arrhythmias is limited by moderate efficacy, ventricular proarrhythmia, and drug-device interactions. This study tested the safety and efficacy of a new dual-chamber ICD to detect and treat atrial as well as ventricular tachyarrhythmias. METHODS AND RESULTS: A dual-chamber ICD (Medtronic 7250 Jewel AF) was implanted in 293 of 303 patients at 49 centers in Europe, Canada, and North America. Specific data were collected at implant and during a mean follow-up period of 7.9+/-4.7 months. There were no clinically evident failures to detect and treat ventricular arrhythmias. In patients with at least one of the dual-chamber detection criteria activated, 1,056 of 1,192 episodes of ventricular tachycardia or fibrillation detected were judged to be appropriate (89% positive predictive accuracy). Therapy efficacy was 100% in the ventricular fibrillation zone and 98% in the ventricular tachycardia zone. Positive predictive accuracy for detection of atrial episodes was 95% (1,052/1,107). For episodes classified as atrial tachycardia by the device, the efficacy of atrial antitachycardia pacing and high-frequency (50-Hz) burst pacing was 55% and 17%, respectively. High-frequency burst pacing terminated 16.8% of episodes classified as atrial fibrillation, and atrial defibrillation had an estimated efficacy of 76%. The actuarial estimates of 6-month complication-free survival and total survival were 88% and 94%, respectively. CONCLUSION: This novel dual-chamber ICD is capable of safely and effectively discriminating atrial from ventricular tachyarrhythmias and of treating atrial tachyarrhythmias without compromising detection and treatment of ventricular tachyarrhythmias.  相似文献   
898.
Uchiyama  H; Barut  BA; Mohrbacher  AF; Chauhan  D; Anderson  KC 《Blood》1993,82(12):3712-3720
Previous studies show that human myeloma-derived cell lines specifically adhere to fibronectin (FN) through very late antigen-4 (VLA-4; alpha 4 beta 1 integrin complex) and RGD-peptide mechanisms, which may contribute to the localization of tumor cells in bone marrow (BM). In these studies, we characterized the adhesion of myeloma- derived cell lines to both normal and myeloma BM stromal cells (BMSCs) and the effect of adhesion on DNA synthesis. Because interleukin-6 (IL- 6) plays an important role in the pathogenesis of multiple myeloma, we also examined the effects of tumor cell adhesion on IL-6 secretion by BMSCs. In 51chromium binding assays, the U266, ARH-77, and IM-9 cell lines showed 52% +/- 12%, 55% +/- 6%, and 47% +/- 7% specific adherence, respectively, to normal BMSCs and 74% +/- 4%, 60% +/- 3%, and 61% +/- 6% specific adherence, respectively, to myeloma BMSCs. In contrast, only 12% to 13% specific binding of HS-Sultan cells to BMSCs was noted. The binding of myeloma cells to BMSCs was partially blocked with anti-beta 1 monoclonal antibody (MoAb), anti-beta 2 integrin MoAb, and excess RGD peptide, suggesting multiple mechanisms for the adhesion of myeloma cell lines to BMSCs. Binding of cell lines to FN or myeloma BMSCs did not affect cell line proliferation; however, adhesion of myeloma cell lines to normal BMSCs decreased DNA synthesis, ie, stimulation indices are 0.1 +/- 0.04, 0.2 +/- 0.1, 0.2 +/- 0.07, and 0.1 +/- 0.06 for the adherent non-IL-6-dependent U266, ARH-77, HS- Sultan, and IM-9 cells, respectively (n = 5, P < .01). In contrast, adherence of IL-6-dependent B9 cells increased their proliferation (stimulation index, 3.2 +/- 0.7). Significant (twofold to eightfold) increases in IL-6 secretion were evident in cell line-adherent (> or = 12 hours) normal and myeloma BMSC cultures. Paraformaldehyde fixation of BMSCs before adhesion completely abrogated IL-6 secretion, suggesting that IL-6 secretion was triggered in BMSCs rather than in cell lines. Partial blocking of cell line adhesion to BMSCs, using anti- beta 1 integrin and anti-beta 2 integrin MoAbs and RGD peptide, also partially blocked the triggering of IL-6 secretion by BMSCs. When cell lines were placed in Transwell inserts and then cultured with either normal or myeloma BMSCs, permitting juxtaposition without cell to cell contact between myeloma cell lines and BMSCs, no increase in IL-6 secretion was observed.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
899.
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