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71.
Background: A number of mutations in the VSX1 and SOD1 genes have been reported to be associated with keratoconus (KC), however the results from different studies are controversial. In this study, we conducted the genotyping of common polymorphisms [VSX1: D144E, H244R, R166W, G160D; SOD1: intronic 7-base deletion (c.169?+?50delTAAACAG)], in a case–control sample panel of the Greek population.

Materials and methods: A case–control panel, with 33 KC patients and 78 healthy controls, were surveyed. DNA from each individual was tested for the VSX1: D144E, H244R, R166W, G160D and SOD1: intronic 7-base deletion (c.169?+?50delTAAACAG) polymorphisms by direct sequencing.

Results: We observed no polymorphisms of the VSX1 gene in the case–control panel. Concerning the SOD1 intronic 7-base deletion (c.169?+?50delTAAACAG), our findings suggest that heterozygous carriers are over-represented among KC cases compared to healthy controls (p?=?0.002).

Conclusions: We cannot confirm the previously reported association of the polymorphism in the VSX1 gene with KC. Our results suggest a possible causative role of SOD1 in the pathogenesis of KC. Further studies are required to identify other important genetic factors involved in the pathogenesis and progression of KC.  相似文献   
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Clinical Rheumatology - Systemic sclerosis is a debilitating autoimmune disease with unknown pathogenesis. The clinical phenotype of fibrosis is preceded by vascular and immunologic aberrations....  相似文献   
75.
The concept of textbook outcome (TO) has recently gained popularity in surgical research and has been used to evaluate the quality or success of different surgical procedures, including hepatopancreatobiliary (HPB) operations. TO consists of individual outcome parameters that each reflect different domains of care including structure, process, and individual outcomes; in turn, the composite TO metric represents the optimal course after a surgical episode. TO can be used to assess patient-level outcomes, hospital performance, center designation and quality metrics. In addition to being an outcome measurement, TO may also be linked to healthcare costs. Future efforts should be directed towards establishing a universal definition of TO in HPB surgery so that surgeons and hospitals can assess and compare outcomes, identify shortcomings and improve real world patient outcomes.  相似文献   
76.
Heart Failure Reviews - Neuromuscular diseases (NMDs) include a broad spectrum of disorders that affect motor unit in every possible site, extending from the cell body of peripheral nerves to the...  相似文献   
77.
Hyperhomocysteinemia is associated with an enhanced risk for cardiovascular disease. Patients with peripheral arterial disease (PAD) show an increased prevalence of hyperhomocysteinemia. A decreased biological activity of nitric oxide (NO) may contribute to homocysteine-associated endothelial dysfunction. This study was designed to investigate whether elevated levels of the endogenous NO synthase inhibitor asymmetric dimethylarginine (ADMA) are involved in endothelial dysfunction in patients with chronic hyperhomocysteinemia and PAD. A total of 76 patients (58 males and 18 females; mean age 65.2 +/- 2.0 years) with PAD were included in the analysis and characterized according to demographic variables and cardiovascular risk factors. Flow-dependent vasodilation (FDD) was determined by high-resolution ultrasound in the radial artery. Total plasma homocysteine (plasma tHcy) and ADMA levels were measured by HPLC. Urinary nitrate was quantified using gas chromatography-mass spectrometry. Patients with plasma tHcy in the highest tertile (n = 27; i.e. > 10.6 micromol/l) had a mean plasma level of 14.4 +/- 1.21 mol/l compared with 9.9 +/- 0.1 micromol/l in those patients in the middle tertile (n = 22; p < 0.05) and 9.4 +/- 0.1 micromol/l in those in the lowest tertile (n = 27; i.e. <9.6 micromol/l; p < 0.05). The hyperhomocysteinemic individuals (highest tertile) had a significantly decreased FDD compared with healthy age-matched controls (n = 15) (7.6 +/- 1.0 vs 13.0 +/- 0.4%; p < 0.05), higher plasma ADMA concentrations (4.0 +/- 0.3 vs 2.6 +/- 0.3 micromol/l; p < 0.05), and a lower urinary nitrate excretion rate (89.5 +/- 13.4 vs 131.3 +/- 17.9 micromol/mmol creatinine; p < 0.05) compared with patients with plasma tHcy in the lowest tertile. Multivariate regression analysis including plasma tHcy, ADMA, total cholesterol, diabetes mellitus, smoking, and systolic blood pressure revealed ADMA as the only significant factor determining FDD (p < 0.05). In conclusion, we demonstrated a stronger relationship between impaired endothelial function and elevated ADMA levels in comparison with plasma tHcy concentrations in patients with PAD and chronic hyperhomocysteinemia. This may raise the question of whether different therapeutical options that interact indirectly with plasma tHcy, i.e. treatment with ACE inhibitors and AT1-receptor blockers to reduce ADMA plasma concentrations or L-arginine, could be a beneficial tool for treating patients with hyperhomocysteinemia.  相似文献   
78.
In the majority (80%) of patients with acute pancreatitis, the disease is self limiting and, after a few days of withholding feeding and intravenous administration of fluids, patients can again be normally fed orally. In a small percentage of patients, the disease progresses to severe necrotic pancreatitis, with an intense systemic inflammatory response and often with multiple organ dysfunction syndrome. As mortality is high in patients with severe disease and as mortality and morbidity rates are directly related to the failure of establishing a positive nitrogen balance, it is assumed that feeding will improve survival in patients with severe disease. The aim of nutritional support is to cover the elevated metabolic demands as much as possible, without stimulating pancreatic secretion and maximizing self-digestion. The administration of either total parenteral nutrition or jejunal nutrition does not stimulate pancreatic secretion. Recently, a series of controlled clinical studies has been conducted in order to evaluate the effectiveness of enteral nutrition with jejunal administration of the nutritional solution. The results have shown that enteral nutrition, as compared to total parenteral nutrition, was cheaper, safer and more effective as regards the suppression of the immunoinflammatory response, the decrease of septic complications, the need for surgery for the management of the complications of acute pancreatitis and the reduction of the total hospitalization period. It did not seem to affect mortality or the rate of non-septic complications. In conclusion, enteral nutrition should be the preferred route of nutritional support in patients with acute pancreatitis.  相似文献   
79.
The frequencies of the hereditary hemochromatosis gene (HFE) mutations C282Y and H63D vary between different populations. There are a limited number of reports regarding the frequency of these mutations in populations of southeastern Europe. Two hundred and sixty-four adult individuals of Greek origin were examined for the C282Y and H63D mutations to determine the allele and genotype frequencies. The HFE gene region of DNA samples extracted from peripheral leukocytes was amplified by the polymerase chain reaction. Restriction enzyme analysis was performed using RSAI for C282Y and MBOI for H63D. None of the 264 individuals carried the mutation C282Y. Forty-three individuals (16.2%) were heterozygous carriers of the H63D allele and 2 were homozygous for this mutation (0.75%). The overall H63D allele prevalence is thus estimated at 8.9%. HFE mutation frequencies were low in the population studied and this may explain, in part, the relative rarity of clinical cases of hereditary hemochromatosis in Greece.  相似文献   
80.
Positive markers in AMA-negative PBC   总被引:5,自引:0,他引:5  
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