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1.
Toll-like receptor 2 (TLR2), a member of the Toll-like receptor family, plays an important role in recognition of, and subsequent immune response activation against, mycobacteria. The genetic polymorphism of TLR2 (arginine to glutamine substitution at residue 753 (Arg753Gln)) has been associated with a negative influence on TLR2 function, which may, in turn, determine the innate host response to mycobacteria. The aim of the present study was to investigate the Arg753Gln single nucleotide polymorphism of the TLR2 gene in tuberculosis (TB) patients compared to healthy controls. A retrospective case/control study was carried out. The Arg753Gln polymorphism of the TLR2 gene was studied in 151 TB patients compared to 116 ethnically and age-matched healthy control subjects. The TLR2 polymorphism (adenine (A) allele) was observed in 17.9 and 7.7% of TB patients and controls, respectively. When the ratios of the three genotypes were compared between the two groups, the AA genotype was found to be more significantly associated with TB. Allele frequencies for guanine (G) and A were found to be 0.95 and 0.05 in the control group and 0.86 and 0.14 in the TB patient group, respectively. The risk of developing TB disease was increased 6.04- and 1.60-fold for carriers of the AA and GA genotypes, respectively. In conclusion, the present data suggest that the arginine to glutamine substitution at residue 753 polymorphism of the Toll-like receptor 2 gene influences the risk of developing tuberculosis.  相似文献   
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Discontinuation of medication is the treatment of choice for patients with chronic daily headache (CDH) who overuse their medications. This treatment may be difficult due to increased headache severity observed in patients immediately after withdrawal. We retrospectively evaluated the efficacy of valproic acid therapy in 66 patients with overuse of CDH medication during withdrawal therapy. Patients were all withdrawn from medications and valproic acid started at 250 mg or 500 mg daily. Forty-two (63.6%) patients had decreased headache severity, including 27.3% objective responses in the first week. At the last visit in the 12th week, 50 patients were headache-free and only one patient had persistent headache. Fifteen patients withdrew from therapy due to side effects and lost to follow-up within this timeframe. Thus, low dose valproic acid appears to be safe and effective in the management of withdrawal therapy.  相似文献   
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Tumor angiogenesis is believed to be related to prognostic factors involved in tumor development and metastasis. Using immunohistochemical methods, we evaluated tumor angiogenesis in 42 early invasive breast cancer patients (T1-2, NO-1-2, M0). Four patients received tamoxifen, 25 patients received CAF or CA, and 15 patients received CMF as adjuvant therapy. The median follow-up was 47 (range 24-119) months. Ten patients (43.5%) in the node-positive group and 2 patients (10.5%) in the node-negative group relapsed (p = 0.019). The mean microvessel count (MVC) was 60.3 3.05 per 200x field (range: 16-95). MVCs of postmenopausal and premenopausal patients were 50.13 +/- 5.74 and 68.64 +/- 4.11, respectively, in the axillary lymph node (ALN)-negative patient group (p = 0.04). Staining was moderate to strong in 13 (68%) ALN-negative and in 17 (74%) ALN-positive patients (p > 0.05), and was also moderate to strong in 82% of premenopausal patients and in 50% of postmenopausal patients (p = 0.037). There was no significant relationship between angiogenesis and p53, nor was angiogenesis significantly associated with the patient ER status and tumor size. No significant correlations were found between OS/DFS and Factor VIII staining or p53 (log rank test, p > 0.05). Of all ALN-negative patients with increased angiogenesis, one patient of the CMF group relapsed, but no recurrence occurred in patients undergoing anthracycline-based chemotherapy (p > 0.05). On the other hand, of all ALN-positive patients with increased angiogenesis, 5/14 patients treated with anthracylcine and 2/2 CMF-treated patients relapsed (p = 0.175). Despite the statistical insignificance, anthracycline-based adjuvant chemotherapy appears to be more effective than CMF as regards relapse prevention particularly in early ALN-positive breast cancer patients with increased angiogenesis. Additional studies are necessary to demonstrate the clinical importance of angiogenesis.  相似文献   
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Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease.  相似文献   
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Asthma and allergic rhinitis are common problems in children and the causative pollen allergens vary according to the geographical area. The aim of this study was to investigate patterns of sensitization to common inhalant allergens, especially pollens, in Turkish children living in the Trakya region and to determine differences between rural and urban areas. Allergen skin testing was prospectively performed on 539 children aged between 4 and 17 years with respiratory allergy. The reaction was considered to be positive if the mean wheal diameter was at least 3 mm greater than that of the negative controls. We detected positive skin reactions in 420 (77.9%) children. Two hundred and eighty-one (52.1%) mite, 277 (51.4%) pollen, 174 (32.3%) mold, 65 (12.1%) animal dander, 12 (2.2%) cockroach and 6 (1.1%) latex skin sensitivities were detected. Among the pollen allergies 173 were cereal pollen (32.1%), 170 grass pollen (31.5%) and 144 tree pollen allergies (26.7%). The most common positive skin test among the pollens was to cultivated wheat (Titicum vulgare) (n = 116, 21,5%), followed by rye grass (Lolium perenne) and orchard grass (Dactylis glomerata). Positive skin reactions to Alternaria, to Candida albicans, and to all pollens except Ulmus competris, Pinus sylvetris, Platanus vulgaris and Tilia platyphyllos, were higher in children with allergic rhinitis than in those with asthma. In children from rural areas, allergic skin reactivity was found to be more common against Candida albicans, sheep dander and all pollens except Corylus avellana, Fraxinus excelsior, Populus alba, Pinus sylvetris, Platanus vulgaris and Chenopodium album, than in urban children. Although Trakya is close to Greece and other Mediterranean countries, this study suggests that the pollens, which sensitize children, are not similar.  相似文献   
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Heart failure is known to be a complication of insulin-dependent (IDDM) and noninsulin-dependent diabetes mellitus (NIDDM) even in the absence of coronary heart disease or hypertension. The mechanisms leading to diabetic cardiomyopathy are unknown. The aim of the study was to characterize structural and functional alterations in hyperinsulinemic Zucker diabetic fatty (ZDF) rats treated with or without insulin. Diabetic animals showed a twofold increase in cardiomyocyte volume with increased left ventricular ANP but not BNP mRNA levels in spite of a reduced plasma renin activity (PRA) 2 months after onset of diabetes compared to nondiabetic littermates. These changes were associated with an increase in left ventricular performance as assessed by echocardiography. Insulin treatment led to a significant increase in body weight (BW), total heart weight, myocardial protein content, and left ventricular mass (LVM). Perivascular fibrosis and laminin thickness were significantly augmented in diabetic rat myocardium irrespective of insulin treatment, whereas interstitial collagen I and fibronectin were similarly found in diabetic and control myocardium. Initial stages of diabetic cardiomyopathy in hyperinsulinemic rats are characterized by cardiomyocyte hypertrophy and enhanced cardiac contractility. It is suggested that hyperinsulinemia may be involved in cardiac hypertrophy.  相似文献   
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In this study, we evaluated the role of the Prostate Imaging–Reporting and Data System (PI-RADS) classification of multiparametric magnetic resonance imaging (mpMRI) to determine the likelihood of prostate cancer (PCa) in patients with haemospermia. Fifty-one patients presenting with haemospermia between 2018 and 2020 were included in this retrospective study. Forty-two of the patients (82.4%) were over 40 years, and the median prostate-specific antigen (PSA) level was 1.4 ng/ml. Fourteen of the patients (27.5%) had recurrent haemospermia. All patients underwent mpMRI, and assessments were classified according to PI-RADS v2. The mpMRI revealed PI-RADS one to four lesions in 10 (19.6%), 30 (58.8%), 6 (11.8%) and 5 (9.8%) patients respectively. One patient with PI-RADS 3 and five with PI-RADS 4 lesions underwent cognitive fusion prostate biopsy depending on MRI findings, and two patients with PI-RADS 4 lesions were diagnosed with PCa. Patients with haemospermia and risk factors, that is aged over 40 years, a high PSA level or familial history of PCa, need a more thorough evaluation with mpMRI.  相似文献   
10.
For a long time, aluminium has been considered as an indifferent element from a toxicological point of view. In recent years, it became clear that aluminium is a potential toxic agent in humans and has been implicated in the pathogenesis of several clinical disorders, such as dementia, respiratory tract disorders and allergic reactions. Chronic exposure to aluminium fumes, inhalation of aluminium and aluminium-oxide powder increase the risk to develop serious central nervous system pathology, in particular Alzheimer's disease and amyotrophic lateral sclerosis (ALS). In the present study, 3 experimental and 1 control group of rats were used to study the effects of aluminium on the central nervous system. Aluminium was injected intracisternally as a single dose (50 micrograms for group I, 100 micrograms for group II and 300 micrograms for group III) to the experimental groups (n = 5 in each group). The same dose was given at 3 months after the first injection to all groups. The control group (n = 5) was intracisternally given a physiological salt solution. Electromyography (EMG) was applied to the rats of the experimental groups. Rats were decapitated at 3 months after the second injections. Spinal cord samples from lumbar and cervical regions were removed and histological examination was performed. Light microscopical investigations revealed severe degeneration in motor neurons of the rats treated with 300 micrograms. Neurofibrillary tangle formation, chromatolysis and abnormal localization of the nuclei were found in swollen perikarya. Extreme loss of motor neurons with "ghost cell" appearance was found in that group. Sections of spinal cords of rats treated with lower doses of aluminium showed a moderate degree of motor neuron damage. EMGs of rats treated with the high dose of aluminium revealed severe acute denervation whereas treatment with lower doses resulted in moderate denervation. We conclude that aluminium may cause severe motor neuron damage in rat spinal cord resembling ALS.  相似文献   
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