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991.
Percutaneously inserted central venous catheters (CVCs) are frequently used for parenteral nutrition (PN) in neonates. Catheter-related sepsis (CRS) is the most commonly reported complication. The aim of this study was to compare sepsis rates between neonates receiving PN by CVC and by peripheral cannula. Neonates were randomized to receive PN either by CVC or by peripheral cannula. Primary outcomes were sepsis rates and efficacy of PN delivery. Interim analysis (49 neonates) revealed no difference in sepsis rates (CVC group 46%, cannula group 40%, p = 0.57). There was a significant discrepancy in PN delivered (median deficit 3.2% in the CVC group, 10.3% in the cannula group, p = 0.0014). After consideration of these findings the study was terminated.  相似文献   
992.
OBJECTIVES

The aim of the study was to examine the inflammatory cytokines in patients with myocardial ischemia to evaluate whether silent ischemia patients exibit any particular cytokine pattern.

BACKGROUND

Silent myocardial ischemia is frequently observed in patients with coronary artery disease. Various endogenous mechanisms control a patient’s perceived intensity of pain. Among them, the inflammatory process and the related cytokine production are known to modulate the threshold for activating the primary afferent nociceptors.

METHODS

Seventy-eight patients with reproducible exercise-induced myocardial ischemia were studied: 34 symptomatic patients, with rest and/or stress angina; 44 asymptomatic patients, with no symptoms during daily life activities or during positive exercise stress test. Venous blood samples were taken from all patients to evaluate the expression of CD11b receptors both on neutrophils and monocytes. Frozen plasma samples (at −80°C) were used to quantify the anti-inflammatory (interleukin-4 and -10, transforming growth factor-β) and the proinflammatory cytokines (tumor necrosis factor-, interferon-γ, interleukin-1β and -6).

RESULTS

In asymptomatic patients lower CD11b receptor expression and higher concentration of anti-inflammatory cytokines were observed. Proinflammatory cytokine production was similar in the two groups.

CONCLUSIONS

The data suggest that an “anti-inflammatory pattern” of cytokine production correlates with silent ischemia and that the immune and inflammatory system activation may be crucial for angina symptoms.  相似文献   

993.
Semaphorin 3E (Sema3E) is a secreted molecule implicated in axonal path finding and inhibition of developmental and postischemic angiogenesis. Sema3E is also highly expressed in metastatic cancer cells, but its mechanistic role in tumor progression was not understood. Here we show that expression of Sema3E and its receptor Plexin D1 correlates with the metastatic progression of human tumors. Consistent with the clinical data, knocking down endogenous expression of either Sema3E or Plexin D1 in human metastatic carcinoma cells hampered their metastatic potential when injected into mice, while tumor growth was not markedly affected. Conversely, overexpression of exogenous Sema3E in cancer cells increased their invasiveness, transendothelial migration, and metastatic spreading, although it inhibited tumor vessel formation, resulting in reduced tumor growth in mice. The proinvasive and metastatic activity of Sema3E in tumor cells was dependent on transactivation of the Plexin D1–associated ErbB2/Neu oncogenic kinase. In sum, Sema3E–Plexin D1 signaling in cancer cells is crucially implicated in their metastatic behavior and may therefore be a promising target for strategies aimed at blocking tumor metastasis.  相似文献   
994.
The prevalence of obesity, especially among the young, is dramatically increasing in the United States. Obesity is associated with accelerated atherosclerosis and increased rates of cardiovascular death. There are many plausible mechanisms by which an increase in adipose tissue could adversely affect the vessel wall. These include the changes in blood pressure, glucose level, lipid/lipoprotein metabolism, and systemic inflammation. In addition, factors secreted by adipose tissue may directly influence vessel wall homeostasis by influencing the function of endothelial cells, arterial smooth muscle cells, and macrophages in the vessel wall. There is general agreement that central, as opposed to peripheral, adipose tissue confers the most cardio-metabolic risk. Although the basis of this differential risk has not been not established, the pattern of gene expression and secretory products in visceral fat would be predicted to be more atherogenic compared with that in subcutaneous peripheral fat. Numerous studies have shown the beneficial effects of weight loss on markers of cardiovascular risk but fewer have demonstrated improvement in direct measures of large vessel disease. The unfolding role of adipose tissue as an important metabolic and secretory organ provides new opportunities for developing more effective approaches for preventing obesity and its atherosclerotic complications.  相似文献   
995.
We evaluated correlates of coronary atherosclerosis, measured by coronary artery calcium, in a racially diverse group of male and female subjects with type 2 diabetes. Age, systolic blood pressure, sex, and race/ethnicity were significant determinants of coronary artery calcium. Among lipoproteins, cholesterol level contained in a particle excluded from direct measures of LDL and HDL cholesterol (designated triglyceride-rich lipoprotein cholesterol) was most strongly linked to coronary artery calcium. Neither inflammatory markers nor metabolic factors correlated with coronary artery calcium in models adjusted for age and sex, but measures of adipose distribution did. Waist-to-hip ratio and the ratio of visceral to total abdominal tissue were positively associated with coronary artery calcium. In fully adjusted multivariate models, the relationship of adiposity measures to coronary artery calcium was no longer significant after inclusion of apolipoprotein B or triglyceride-rich lipoprotein cholesterol. Traditional risk factors and race/ethnicity remain important correlates of coronary artery calcium in a cohort at elevated risk of cardiovascular disease because of type 2 diabetes. Adiposity measures are significantly associated with coronary artery calcium score, but their importance may be largely explained by apolipoprotein B or triglyceride-rich lipoprotein cholesterol.  相似文献   
996.
Neoangiogenesis and inflammation have a pivotal role in atherosclerosis. Observations support the hypothesis that calcified aortic valve stenosis is an inflammatory process, similar to atherosclerosis in tissue features and risk factors. We studied 2 groups of cases: 47 were affected by hemodynamic atherosclerotic carotid plaque (group 1) and 35 by severe calcified aortic valve stenosis (group 2). We compared the groups for atherosclerosis risk factors, morphologic features, and immunohistochemical phenotypes. In both groups, men, smokers, and hypertensive subjects prevailed, and histologic analysis showed an elevated score for T-lymphocyte infiltrates, neoangiogenesis, calcium, and sclerosis. Adhesion molecule expression was present in both lesions. Expression of intercellular adhesion molecule 1 correlated with inflammatory infiltrates (group 1, P = .0007; group 2, P = .06). Neoangiogenesis also correlated with inflammatory infiltrates (group 1, P = .035; group 2, P = .045). In valves, neoangiogenesis correlated with calcium (P = .048). Carotid plaque and calcified valve stenosis showed common risk factors and biologic hallmarks of a chronic inflammatory process. Inflammation and neoangiogenesis have a crucial role in plaque evolution and in the progression of aortic valve stenosis.  相似文献   
997.
OBJECTIVE: To compare the efficacy and safety of the recommended usual starting and next highest doses of ezetimibe/ simvastatin and atorvastatin in patients with type 2 diabetes mellitus and hypercholesterolemia. PATIENTS AND METHODS: This double-blind, multicenter study (June 22 to December 7, 2005) consisted of adult patients randomized to the recommended usual starting (ezetimibe/simvastatin, 10/20 mg/d, vs atorvastatin, 10 or 20 mg/d) or next highest (ezetimibe/simvastatin, 10/40 mg/d, vs atorvastatin, 40 mg/d) doses. Efficacy end points included percent changes from baseline in low-density lipoprotein cholesterol (LDL-C) levels (primary) and proportion of patients attaining LDL-C levels less than 70 mg/dL (secondary). RESULTS: A total of 1229 patients participated in the study. Significantly greater mean reductions were found in LDL-C levels with ezetimibe/simvastatin, 10/20 mg/d (-53.6%; 95% confidence interval [CI], -55.4% to -51.8%), than with atorvastatin, 10 mg/d (-38.3%; 95% CI, -40.1% to -36.5%; P < .001) or 20 mg/d (-44.6%; 95% CI, -46.4% to -42.8%; P < .001), and with ezetimibe/simvastatin, 10/40 mg/d (-57.6%; 95% CI, -59.4% to -55.8%), vs atorvastatin, 40 mg/d (-50.9%; 95% CI, -52.7% to -49.1%; P < .001). Ezetimibe/simvastatin was also superior to atorvastatin in attainment of LDL-C levels less than 70 mg/dL (P < .001 for all dose comparisons). Significantly better improvements with ezetimibe/simvastatin than with atorvastatin (P < or = .001) were observed for total cholesterol, high-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol. Ezetimibe/ simvastatin, 10/20 mg/d, reduced high-sensitivity C-reactive protein and triglyceride levels significantly more than atorvastatin, 10 mg/d (P = .02), with comparable reductions at other doses. Incidences of clinical adverse events, including serious drug-related and prespecified gastrointestinal-, gallbladder-, and hepatitis-related allergic reactions or rash events, and laboratory adverse events, including repeated elevation of hepatic transaminases or creatine kinase levels, were similar for both treatments. CONCLUSION: Ezetimibe/simvastatin provided additional lipid-modifying benefits over atorvastatin monotherapy at the recommended usual starting and next highest doses in patients with type 2 diabetes. Both treatments were generally well tolerated.  相似文献   
998.
Canalicular bile is formed by the osmotic filtration of water in response to osmotic gradients generated by active transport at the apical and basolateral plasma membrane domains of hepatocytes. We recently demonstrated that mixed plasma membrane fractions isolated from rat hepatocyte couplets contain lipid microdomains ("rafts") enriched in cholesterol and sphingolipids and AQP8 and 9. We isolated lipid microdomains from hepatocyte apical and basolateral plasma membrane domains using Triton X-100 as detergent, and characterized their lipid and protein composition. A Triton-insoluble band ("raft fraction") at the 5%/30% sucrose interface in both apical and basolateral fractions was enriched for alkaline phosphatase (apical) and Na/K ATPase (basolateral) and was negative for amino peptidase-N. This detergent-insoluble band was also positive for caveolin-1 (a "raft" associated protein) and negative for clathrin (a "raft" negative protein). Lipid analysis showed that, the Triton-insoluble fraction was highly enriched in cholesterol and sphingolipids. Immunofluorescence staining on hepatocyte couplets for both caveolin-1 and cholera toxin B showed a punctate distribution on both the apical and basolateral plasma membranes, consistent with localized membrane microdomains. Dot blot analysis showed that the "raft" associated ganglioside GM1 was enriched in the detergent-insoluble fraction both domains. Furthermore, exposure of isolated hepatocytes to glucagon, a choleretic agonist, significantly increased the expression of AQP8 associated with the apical microdomain fractions but had no effect on AQP9 expression in the basolateral microdomain fractions. In conclusion, "rafts" represent target microdomains for exocytic insertion and retrieval of "flux proteins", including AQPs, involved in canalicular bile secretion.  相似文献   
999.
1000.
Skin and soft tissue infections (SSTIs) are a common cause of hospital admission among elderly patients, and traditionally have been divided into complicated and uncomplicated SSTIs. In 2010, the FDA provided a new classification of these infections, and a new category of disease, named acute bacterial skin and skin structure infections (ABSSSIs), has been proposed as an independent clinical entity. ABSSSIs include three entities: cellulitis and erysipelas, wound infections, and major cutaneous abscesses This paper revises the epidemiology of SSTIs and ABSSSIs with regard to etiologies, diagnostic techniques, and clinical presentation in the hospital settings. Particular attention is owed to frail patients with multiple comorbidities and underlying significant disease states, hospitalized on internal medicine wards or residing in nursing homes, who appear to be at increased risk of infection due to multi-drug resistant pathogens and treatment failures. Management of ABSSSIs and SSTIs, including evaluation of the hemodynamic state, surgical intervention and treatment with appropriate antibiotic therapy are extensively discussed.  相似文献   
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