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11.
Gao HZ Kobayashi K Tabata A Tsuge H Iijima M Yasuda T Kalkanoglu HS Dursun A Tokatli A Coskun T Trefz FK Skladal D Mandel H Seidel J Kodama S Shirane S Ichida T Makino S Yoshino M Kang JH Mizuguchi M Barshop BA Fuchinoue S Seneca S Zeesman S Knerr I Rodés M Wasant P Yoshida I De Meirleir L Abdul Jalil M Begum L Horiuchi M Katunuma N Nakagawa S Saheki T 《Human mutation》2003,22(1):24-34
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
12.
Yazicioglu M Oner N Celtik C Okutan O Pala O 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》2004,22(4):183-190
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
13.
Yusuf Orhan Adil Azezli Mahmut Çarin Ferihan Aral Ergin Sencer Senay Molvalılar 《Journal of clinical immunology》1993,13(5):339-343
To evaluate the association of HLA types with Turkish patients with Graves' disease, HLA typing, clinical findings, and thyroid antibodies were correlated. The HLA types, clinical findings (ophthalmopathy and age at onset), and thyroid stimulating hormone (TSH) receptor (TRAb) and antithyroid microsomal antibodies (MAb) were analyzed. Seventy Turkish patients with Graves' disease and 306 control subjects were assessed. Serological HLA typing was performed in HLA A, B, C, DR, and DQ loci. There was a significantly increased prevalence of HLA B8, B49, DR3, DR4, and DR10 in Graves' disease. The association of Graves' disease with HLA DR3 was found to be less strong than previously described. The HLA DR4 antigen may contribute to the predisposition of Graves' disease in Turkey. The results suggest that HLA B7, B13, DR7, DQw2, and DQw3 may confer a protective effect for Graves' disease in Turkey. Patients carrying HLA B12, B18, and B44 haplotypes had a tendency to develop the disease at a later age. The difference from the other studies may be the result of the selection of the controls; in part, of the variability in serological typing reagents; and, also, of the rather weak HLA associations with the disease.This study was presented in part at the Annual Meeting of the National Endocrinology and Diabetes Association, Bursa, Turkey, May 25–28, 1992. 相似文献
14.
Yamac D Celenkoglu G Coskun U Akyurek N Akcali Z Dursun A Koybasioglu F 《Pathology, research and practice》2005,201(7):497-502
A relationship between cyclooxygenase-2 (COX-2) expression and the pathogenesis of colorectal cancer has been reported in recent studies. Moreover, it has been indicated that COX-2 expression may have a prognostic role in colorectal cancer patients. In this study, we investigated the prognostic significance of COX-2 expression in 83 patients with colorectal cancer. COX-2 expression was assessed using immunohistochemical methods and was evaluated by grading both staining intensity and staining extension. The relationships between COX-2 expression and clinicopathological features of the patients and patient survival were evaluated. There was no relationships between COX-2 expression and tumor size (tm < 3 cm or tm > or = 3 cm), tumor histopathological differentiation (poorly differentiated or moderately + well differentiated), number of metastatic lymph nodes (< 4 or 3 > or = 4), histopathology of the tumor, localization of the tumor (colon or rectum), distant metastasis, and vascular invasion of the tumor. In the multivariate analysis, COX-2 expression was not found as an independent prognostic factor. We demonstrated that COX-2 expression was not correlated with clinicopathological characteristics of colon carcinoma and disease outcome. 相似文献
15.
16.
Myocardial hypertrophy and enhanced left ventricular contractility in Zucker diabetic fatty rats. 总被引:5,自引:0,他引:5
Sabine Fredersdorf Christian Thumann Coskun Ulucan Daniel P Griese Andreas Luchner Günter A J Riegger Eckhard P Kromer Joachim Weil 《Cardiovascular pathology》2004,13(1):11-19
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
17.
Mert Kilic Bilgen Coskun Metin Vural Ahmet Musaoglu Tarik Esen Mevlana Derya Balbay 《Andrologia》2021,53(5):e14041
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
18.
Adil M. Al-Nahhas Seishi Jinnouchi Constantinos Anagnostopoulos Wolfgang Hirsch Tom Heary V. Ralph McCready 《European journal of nuclear medicine and molecular imaging》1995,22(2):148-153
Benign myocardial uptake of technetium-99m labelled phosphates, not related to cardiac or metabolic disorders, has been documented except in the case of99mTc-methylene diphosphonate (MDP). The aim of this study was to assess the frequency of myocardial uptake and its possible association with malignant tumours in general and prostatic carcinoma in particular. We reviewed bone scintigrams performed with either99mTc-hydroxydiphosphonate (HDP) or99mTc-MDP over a period of more than 2 years for all patients with prostatic carcinoma and a matching group of patients suffering from other malignant and non-malignant disorders. A total of 965 scintigrams of 812 patients (males=559, females=253; age range 50–91 years, average age 69.2 years) were reviewed. Increased myocardial uptake was detected in 19 scintigrams (MDP=13, HDP=6) of 18 patients (17 males, one female). Most of the male patients with increased myocardial uptake had prostatic carcinoma (13/17) and were over 80 years of age (12/17). All patients were free of any cardiac or noncardiac disorder that might account for such uptake. When scintigraphy was repeated in the same patient, the uptake of99mTc-HDP was more diffuse and of higher grade than that of99mTc-MDP Benign myocardial uptake of99mTc-MDP is more common than previously thought. Although uptake of radiophosphates is attributed to asymptomatic atherosclerotic changes associated with old age, a strong association with prostatic carcinoma exists which may indicate variations in the bone: soft tissue affinity of different MDP complexes. 相似文献
19.
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
20.
Complications of gynaecological laparoscopy--a retrospective analysis of 3572 cases from a single institute. 总被引:3,自引:0,他引:3
Three thousand, five hundred and seventy-two laparoscopic procedures were analysed retrospectively from a single institution between 1996 and 2003. Operations were classified into four groups as diagnostic laparoscopy (386, 10.8%), minor (1092, 30.5%), major (1866, 52.4%) and advanced (228, 6.5%) laparoscopic procedures. Overall, 67 (1.88%) complications occurred. The complication rates were 1.81%, 1.37%, 1.82% and 4.82% in the respective groups. One death (0.03%) occurred due to aortic injury during insertion of the principal intraumbilical trocar. Complications during insertion of the Verres needle, principal and accessory trocars were noted in 25 cases (38.2%) and were comparable among the four groups. Intraoperative complications occurred in 32 patients (47.8%) encountered mainly in the major and advanced groups. Overall, acute postoperative complications occurred in 10 (14.9%) patients. Despite advanced technology and experience, complications during the installation phase of laparoscopy remain a major cause of significant morbidity and most operative complications occurred in advanced operative procedures. Complications associated with all types of laparoscopic procedures should not be underestimated. 相似文献