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51.
The aim of this study was to investigate the effect of desferrioxamine on peroxynitrite-mediated damage in erythrocytes by measuring the 3-nitrotyrosine level and glutathione peroxidase and Na(+)-K(+) ATPase activities in vitro. 3-Nitrotyrosine levels were determined by HPLC; glutathione peroxidase and Na(+)-K(+) ATPase activities were measured by spectrophotometry. Peroxynitrite increased the 3-nitrotyrosine level but decreased both enzyme activities. In the presence of desferrioxamine, glutathione peroxidase activity was increased with a decrease in the 3-nitrotyrosine level. Desferrioxamine was found to possess an important antioxidant activity as assessed in an in vitro system, reducing protein nitration, restoring enzyme activities and maintaining erythrocyte membrane integrity.  相似文献   
52.
The aim is to examine whether the changes in pleural fluid interleukin (IL)-1beta, IL-2, IL-6, and IL-8 levels were significant in differential diagnosis of childhood pleural effusions. IL-1beta, IL-2, IL-6, and IL-8 levels in pleural fluids of all 36 patients were measured. The levels of IL-1beta, IL-2, IL-6, and IL-8 in pleural fluids were statistically significantly higher in the transudate group compared with those of the exudate group. The levels of IL-1 beta, IL-6, and IL-8 were also found to be statistically significantly higher in the empyema group compared with both the parapneumonic and the tuberculous pleural effusion groups. The levels of IL-2 and IL-6 were detected to be statistically significantly higher in the tuberculous pleural effusion group in comparison with those of the parapneumonic effusion group. The results showed that pleural fluids IL-1beta, IL-2, IL-6, and IL-8 could be used in pleural fluids exudate and transudate distinction.  相似文献   
53.
A series of 8,9-disubstituted adenines (4, 5, 8), 6-substituted aminopurines (10–13) and 9-(p-fluorobenzyl/cyclopentyl)-6-substituted aminopurines (16, 17, 19–30) have been prepared and the antimicrobial activities of these compounds against Staphylococcus aureus, methicillin-resistant S. aureus (MRSA, standard and clinical isolate), Bacillus subtilis, Escherichia coli and Candida albicans were evaluated. 6-[(N-phenylaminoethyl)amino]-9H-purine (12) which has no substitution at N-9 position and 9-cyclopentyl-6-[(4-fluorobenzyl)amino]-9H-purine (24) exhibited excellent activity against C. albicans with MIC 3.12 μg/mL. These compounds displayed better antifungal activity than that of standard oxiconazole. Furthermore, compound 22 carrying 4-chlorobenzylamino group at the 6-position of the purine moiety exhibited comparable antibacterial activity with that of the standard ciprofloxacin against both of the drug-resistant bacteria (MRSA, standard and clinical isolate).  相似文献   
54.
Insulin-dependent diabetes mellitus (IDDM) is a chronic disease characterized by T-cell-dependent autoimmune destruction of the insulin-producing beta cells in the pancreatic islets of Langerhans, resulting in an absolute lack of insulin. T cells are activated in response to islet-dominant autoantigens, the result being the development of IDDM. Insulin is one of the islet autoantigens responsible for the activation of T-lymphocyte functions, inflammatory cytokine production, and development of IDDM. The aim of this study was to investigate serum concentrations of interleukin (IL)-1beta, IL-2, IL-6, and tumor necrosis factor (TNF)-alpha in children IDDM. The study population consisted of 27 children with IDDM and 25 healthy controls. Children with IDDM were divided into three subgroups: (1) previously diagnosed patients (long standing IDDM) (n : 15), (2) newly diagnosed patients with diabetic ketoacidosis (before treatment) (n : 12), and (3) newly diagnosed patients with diabetic ketoacidosis (after treatment for two weeks) (n : 12). In all stages of diabetes higher levels of IL-1beta and TNF-alpha and lower levels of IL-2 and IL-6 were detected. Our data about elevated serum IL-1beta, TNF-alpha and decreased IL-2, IL-6 levels in newly diagnosed IDDM patients in comparison with longer standing cases supports an activation of systemic inflammatory process during early phases of IDDM which may be indicative of an ongoing beta-cell destruction. Persistence of significant difference between the cases with IDDM monitored for a long time and controls in terms of IL-1beta, IL-2, IL-6, and TNF-alpha supports continuous activation during the late stages of diabetes.  相似文献   
55.
Limb-girdle muscular dystrophy (LGMD) is a genetically heterogeneous group of inherited muscular disorders manifesting symmetric, proximal, and slowly progressive muscle weakness. Using Affymetrix 250K SNP Array genotyping and homozygosity mapping, we mapped an autosomal-recessive LGMD phenotype to the telomeric portion of chromosome 8q in a consanguineous Turkish family with three affected individuals. DNA sequence analysis of PLEC identified a homozygous c.1_9del mutation containing an initiation codon in exon 1f, which is an isoform-specific sequence of plectin isoform 1f. The same homozygous mutation was also detected in two additional families during the analysis of 72 independent LGMD2-affected families. Moreover, we showed that the expression of PLEC was reduced in the patient's muscle and that there was almost no expression for plectin 1f mRNA as a result of the mutation. In addition to dystrophic changes in muscle, ultrastructural alterations, such as membrane duplications, an enlarged space between the membrane and sarcomere, and misalignment of Z-disks, were observed by transmission electron microscopy. Unlike the control skeletal muscle, no sarcolemmal staining of plectin was detected in the patient's muscle. We conclude that as a result of plectin 1f deficiency, the linkage between the sarcolemma and sarcomere is broken, which could affect the structural organization of the myofiber. Our data show that one of the isoforms of plectin plays a key role in skeletal muscle function and that disruption of the plectin 1f can cause the LGMD2 phenotype without any dermatologic component as was previously reported with mutations in constant exons of PLEC.  相似文献   
56.
Ventricular hypertrabeculation/noncompaction is a morphologic and functional anomaly of myocardium characterized by prominent trabeculae accompanied by deep recessus. Dilated cardiomyopathy with left ventricular failure is observed in these patients, while the cause or pathophysiologic nature of this complication is not known. Anti-troponin antibodies are formed against circulating cardiac troponins after an acute coronary event or conditions associated with chronic myocyte necrosis, such as dilated cardiomyopathy. In present study, we aimed to investigate cardiac troponins and anti troponin autoantibodies in ventricular noncompaction/hypertrabeculation patients with/without reduced ejection fraction. A total of 50 patients with ventricular noncompaction and 23 healthy volunteers were included in this study. Noncompaction/hypertrabeculation was diagnosed with two-dimensional echocardiography using appropriate criteria. Depending on ejection fraction, patients were grouped into noncompaction with preserved EF (LVEF >50%, n = 24) and noncompaction with reduced EF (LVEF <35%, n = 26) groups. Troponin I, troponin T, anti-troponin I IgM and anti-troponin T IgM were measured with sandwich immunoassay method using a commercially available kit. Patients with noncompaction had significantly higher troponin I (28.98±9.21 ng/ml in NCNE group and 28.11±10.42 ng/ml in NCLE group), troponin T (22.17±6.97 pg/ml in NCNE group and 22.78±7.76 pg/ml in NCLE group) and antitroponin I IgM (1.92±0.43 µg/ml in NCNE group and 1.79±0.36 µg/ml in NCLE group) levels compared to control group, while antitroponin T IgM and IgG were only elevated in patients with noncompaction and reduced EF (15.81±6.52 µg/ml for IgM and 16.46±6.25 µg/ml for IgG). Elevated cardiac troponins and anti-troponin I autoantibodies were observed in patients with noncompaction preceding the decline in systolic function and could indicate ongoing myocardial damage in these patients.  相似文献   
57.
Cytokine genes are important for researching cancer predisposition to cancers that elicit anti-tumor immune response. In this study, we investigated the association between breast cancer and tumor necrosis factor alpha (TNF-α) -308 (G>A), TNF-β +252 (A>G), and interferon gamma (IFN-γ) +874 (T>A) gene polymorphisms in a Turkish population. This study involved 204 female breast cancer patients and 204 healthy female controls. Genomic DNA was extracted from EDTA-preserved peripheral venous blood of patients and controls by a salting-out method and analyzed by polymerase chain reaction, allele-specific oligonucleotide polymerase chain reaction, and restriction fragment length polymorphism. TNF-α -308 genotype was found to have no effect on breast cancer susceptibility. However, there were statistically significant differences between the genotype frequencies of patients and controls for TNF-β polymorphism (p?=?0.016) and the allele and genotype frequencies for the IFN-γ polymorphism (p?=?0.0312 and p?=?0.001, respectively). In the composite genotype analysis, the TNF-α/β GAAG composite genotype (p?=?0.0424), the TNF-α/IFN-γ GGTT and GATT composite genotypes (p?=?0.0296 and p?=?0.0129, respectively), the TNF-β/IFN-γ AGTT composite genotype (p?=?0.0003), and the TNF-α/β/IFN-γ GGAGTT and GAAGTT composite genotypes (p?=?0.0437 and p?=?0.0038, respectively) were estimated to have a protective effect against breast cancer. However, the TNF-α/IFN-γ GGTA composite genotype is a risk factor for breast cancer (p?=?0.0156). In conclusion, TNF-β +252GG genotype was found more frequent in Turkish breast cancer patients than controls and IFN-γ TA+AA genotypes were estimated to increase breast cancer risk significantly in Turkish population.  相似文献   
58.
Background: We aimed to investigate serum prolidase activity and to investigate its association with oxidative–antioxidative status in patients with developmental dysplasia of the hip (DDH).

Methods: Oxidative status parameters, including lipid hydroperoxide (LOOH), total oxidant status (TOS), and the oxidative stress index (OSI), and antioxidative status parameters, free sulfhydryl groups (Total –SH), and total antioxidative capacity (TAC), as well as serum prolidase activity were assessed in patients with DDH (n?=?93), and in healthy controls (n?=?82). The severity of dysplasia was evaluated according to the Tonnis grading system.

Results: Serum prolidase activity and the oxidant parameters (LOOH, TOS, and OSI) were significantly higher and the antioxidant parameters (Total –SH and TAC) were significantly lower in patients with DDH compared to the controls (P?P?P?Conclusion: Increased levels of serum prolidase activity, LOOH, TOS, and OSI, and decreased levels of total –SH and TAC, may be associated with DDH, and these parameters may be useful adjunctive tools to assess the severity of DDH.  相似文献   
59.
The objective of this study was to investigate serum paraoxonase and arylesterase activities, and lipid hydroperoxide (LOOH) and total thiol (total free sulfhydryl groups, -SH) levels along with lipid parameters in patients with knee osteoarthritis. Thirty-six patients with knee osteoarthritis and 30 healthy individuals were enrolled in the study. Serum paraoxonase and arylesterase activities were measured spectrophotometrically. LOOH levels were measured by ferrous oxidation with xylenol orange assay (FOX-2). Serum high-density lipoprotein-cholesterol (HDL-C), -SH levels, paraoxonase and arylesterase activities were significantly lower in the patient group than those in the controls (P < 0.05, for all), while LOOH and low-density lipoprotein (LDL) levels were significantly higher. In conclusion, paraoxonase and arylesterase activities were decreased significantly in patients with knee osteoarthritis. Lower serum paraoxonase-1 activity and lower level of HDL-C seem to be related to increased oxidative stress and inflammatory condition in these patients. It is known that paraoxonases reduce oxidative stress in serum and tissues thereby protecting against cardiovascular disease, particularly atherosclerosis. Thus, decreased paraoxonase and arylesterase activities play a role in the pathogenesis of atherosclerosis through increased susceptibility to lipid peroxidation in patients with osteoarthritis.  相似文献   
60.
An extracellular alpha-galactosidase from the culture filtrate of Aspergillus flavipes grown on melibiose as a carbon source was partially purified by hydroxylapatite and diethylaminoethylcellulose chromatographies. Electrophoretic analysis showed protein bands corresponding to alpha-galactosidase and invertase activities. The optimum pH and temperature were determined as 4.5-5.0 and 45 degrees C, respectively. The Km value for p-nitrophenyl-alpha-d-galactopyranoside was found to be 1.89 mm. The results reported in this study indicate that Aspergillus flavipes is indeed an active source of extracellular alpha-galactosidase.  相似文献   
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