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Biomedical subjects

A Dursun

Publications and source records attributed to A Dursun.

At least 19 recordsLinked to original sources
PubMed2006

Audiologic findings in children with biotinidase deficiency in Turkey.

OBJECTIVE: Biotinidase deficiency is an autosomal recessively inherited disorder characterized by neurological and cutaneous features, including sensorineural hearing loss. Although many features of the disorder are reversible following treatment with biotin, the hearing loss appears to be irreversible. In the present study, hearing status of patients with biotinidase deficiency is characterized in a Turkish population. METHODS: Subjective and objective audiologic tests were performed on 20 children with profound biotinidase deficiency. RESULTS: Sensorineural hearing loss occurs in approximately 55% of the children with biotinidase deficiency. The hearing loss varies in severity from mild to profound hearing loss. In children diagnosed immediately after birth because they had an older sibling with the disorder, statistically significant differences were found between ABR results and age of diagnosis (p<0.05). Greater prolongation in ABR latencies were observed in the late-diagnosed children compared to that in the early-diagnosed children (p<0.05). CONCLUSION: Early diagnosis is important to prevent peripheral and central hearing loss. Children with biotinidase deficiency who have hearing loss are likely at increased risk for having speech and language problems. If hearing aids do not provide sufficient amplification, cochlear implantation may be indicated in these children. Therefore, it is important to test the hearing thresholds of these children with hearing aids and evaluate their language development.

Adolescent↗
PubMed2006

Neurocutaneous melanosis associated with Dandy-Walker malformation.

Neurocutaneous melanosis is an uncommon congenital disorder consisting of benign or malignant melanocytic tumors of the leptomeninges with large or numerous cutaneous congenital melanocytic nevi. The Dandy-Walker malformation occurs as an enlarged posterior fossa with high insertion of the tentorium, hypoplasia or aplasia of the cerebellar vermis, and cystic dilatation of the fourth ventricle. To our knowledge, the association of these two conditions has been reported only 14 times. In this article, we present a newborn patient with neurocutaneous melanosis associated with Dandy-Walker malformation, which was diagnosed by magnetic resonance imaging.

Dandy-Walker Syndrome↗
PubMed2006

A Turkish case with molybdenum cofactor deficiency.

Molybdenum cofactor deficiency (MIM 252150) is a rare progressive neurodegenerative disorder with about 100 cases reported worldwide. We have identified a male with molybdenum cofactor deficiency and analyzed the molybdenum cofactor synthesis (MOCS)1 gene, MOCS2 gene, MOCS3 gene and GEPH gene. We homozygously identified the CGA insertion after A666 of the MOCS1 gene which produces arginine insertion at codon 222 of MOCS1A. The parents, his brother and his sister who did not have any symptoms were heterozygous for the same mutation. This region was highly conserved in various species. The N-terminal part of MOCS1 a protein is suggested to form the central core of the protein and be composed of an incomplete [(alpha/beta)6] triosephosphate isomerase (TIM) barrel with a lateral opening that is covered by the C-terminal part of the protein. The insertion is located in the loop connecting the fifth beta strand to the sixth alpha helices of the TIM barrel structure. This arginine insertion would induce the conformation change and the lack of the activity.

Arginine↗
PubMed2006

Three-field lymph node dissection in the treatment of thoracic esophageal carcinoma: the Turkish experience.

The role of extended lymphatic dissection on the prognosis and outcome of thoracic esophageal carcinoma is still controversial. The aim of this study was to determine the impact of three-field lymphatic dissection on the survival and recurrence rates of patients with thoracic carcinoma of the esophagus. Forty-six patients with primary squamous cell carcinoma of the thoracic esophagus underwent esophagectomy with three-field lymphatic dissection between 1992 and 2003. Recurrence and survival rates were examined as well as complications. Overall survival for the patients was 45.6 months and 5-year survival rate was 56%. Five-year survival rates for patients with Stage 2A, 2B, 3 and 4 were 68%, 0%, 53% and 33%, respectively. There was no Stage 1 patient. Mean disease-free survival was 41.4 months. Sixty three percent of patients had node-negative disease (5-year survival rate, 68.9%) and 37% had nodal metastases (5-year survival rate, 33.7%) (P = 0.002). Surgical morbidity was seen in 35 patients (76.1%). Conclusively, lymph node involvement in patients with thoracic esophageal carcinoma is the major determinant of prognosis and survival. Extended lymphatic dissection provides higher disease-free and overall survival rates and our study revealed the highest survival rate for thoracic esophageal carcinoma, to best of our knowledge.

Adult↗
PubMed2006

The effects of calcipotriol and methylprednisolone aseponate on bcl-2, p53 and ki-67 expression in psoriasis.

OBJECTIVE: The decrease of physiological apoptosis in the psoriatic lesions is thought to be involved in the pathogenesis of psoriasis, and induction of apoptosis was shown to contribute to the regression of psoriatic hyperplasia. In the present study, we compared the effects of calcipotriol and methylprednisolone aseponate (MPA) treatments on bcl-2, p53 and ki-67 expressions in psoriatic patients in order to define a relationship between regulation of apoptosis and healing process in psoriasis. METHODS: Thirty psoriatic patients with stable and moderate chronic plaque psoriasis applied either calcipotriol or MPA ointment for 6 weeks twice daily. Evaluation of bcl-2, p53 and ki-67 positivity was performed at baseline and was repeated at sixth week for each therapy. RESULTS: The mean percentage of positive keratinocytes was 8.63 +/- 7.15% for p53, 20.66 +/- 14.45% for ki-67, and 3.74 +/- 2.83% for bcl-2 in psoriatic skin at baseline. Normal skin values were 3.27 +/- 3.21% for p53, 4.93 +/- 4.77% for ki-67, and 1.80 +/- 0.41% for bcl-2. The psoriatic skin showed higher ki-67 (P < 0.05) and bcl-2 (P < 0.05) expression rates when compared to normal skin. The p53 positivity observed in psoriatic skin and normal skin was not significantly different (P > 0.05). Following calcipotriol and MPA treatments, there was a significant reduction in p53 and ki-67 positivity accompanied by an increase in bcl-2 positivity (P < 0.05 each). No significant differences were found at sixth week between calcipotriol and MPA groups with respect to p53, ki-67 and bcl-2 positivity (P > 0.05). The post-treatment psoriatic skin showed lower expression of p53, higher expressions of ki-67 and bcl-2 when compared to normal skin (P < 0.05 each). CONCLUSION: The results of this study provide evidence that both calcipotriol and MPA decrease the p53 and ki-67 expression and increase bcl-2 expression. However, it should further be elucidated if these changes were the common behaviour of psoriatic keratinocytes to any antipsoriatic medication.

Administration, Topical↗
PubMed2005

Detection of Candida albicans by culture, serology and PCR in clinical specimens from patients with ulcerative colitis: re-evaluation of an old hypothesis with a new perspective.

The relationship between inflammatory bowel disease and microorganisms was evaluated. The presence of Candida albicans-specific IgM and IgG antibodies in serum samples and the presence of C. albicans in stool and colonal mucosa samples of the patients did not exhibit any significant difference between 21 patients in active stage and 15 patients in remission of ulcerative colitis (UC) (compared with 19 control patients). The invasion of yeast cells to the colonal mucosa was demonstrated by detecting C. albicans DNA using specific PCon1, PCon2, and PspA2 primers in PCR assay. Eighteen of 36 patients (50%) were found to be DNA positive while in 19 controls only 4 (21%) were found to be positive. The presence of DNA in the association of the positive serological reactivity is suggested as an important diagnostic marker of UC.

Antibodies, Fungal↗
PubMed2005

MEFV gene is a probable susceptibility gene for Behçet's disease.

OBJECTIVE: Behçet's disease (BD) is a rare, chronic, multisystem inflammatory disorder. The prevalence of BD is higher in the Middle Eastern and Mediterranean populations. Another chronic inflammatory disease, familial Mediterranean fever (FMF), is also known to be highly prevalent in these populations. The prevalence of BD is higher in the FMF patient population than in populations known to be rich in BD . Both BD and FMF have some pathophysiological features in common and they result from inappropriate activation of neutrophils. Clinical manifestations of both diseases can mimic each other and the coexistence of both diseases in the same patient has been reported. Given that BD and FMF have similar pathophysiological, epidemiological, and clinical features, we hypothesized that the gene responsible for FMF, MEFV, may also play a role in the pathogenesis of BD. METHODS: Forty-two BD patients who had no symptoms and family history for FMF and 66 healthy controls were screened for common MEFV gene mutations (E148Q, M680I, M694V, and V726A). RESULTS: Fifteen patients (36%) displayed MEFV mutations (nine M694V, five E148Q, and one M680I) and mutation rates were significantly elevated compared to 66 (11%) healthy controls (p = 0.0034). CONCLUSION: The occurrence of frequent MEFV mutations in BD patients suggests that the MEFV gene is involved in the pathogenesis of Behçet's disease.

Adult↗
PubMed2005

The effect of oral L-carnitine supplementation on the lipid profiles of hyperlipidaemic children.

AIM: To investigate the carnitine status and the effect of carnitine supplementation on serum lipid profiles in children with hyperlipoproteinaemia, a clinical open trial was conducted at Hacettepe University Ihsan Dogramaci Children's Hospital, Section of Nutrition and Metabolism. METHODS: Patients were given carnitine at a dose of 100 mg/kg/d for 12 wk. Blood samples for the determination of lipid profile and carnitine levels and urine samples for carnitine levels were obtained on admission, at week 4 and week 12 of the study period. RESULTS: A total of 41 children were enrolled in the study: 20 patients had type II heterozygotes, eight patients had type II homozygotes, three patients had type III, six patients had type V and four patients had secondary hyperlipidaemias. Serum and urine carnitine levels were within normal limits on admission. No significant correlations were found between serum carnitine levels and serum lipid profiles. Serum HDL and apolipoprotein A-I decreased significantly during the 12 wk of intervention in type II heterozygotes. In type II homozygotes, total cholesterol and LDL levels at weeks 4 and 12 increased significantly compared to initial levels. No significant change was noted for lipid parameters in hyperlipoproteinaemia type V. CONCLUSION: The results of this trial demonstrated that carnitine supplementation was of no benefit for children with hyperlipidaemias, especially in primary hyperlipoproteinaemia type II heterozygotes, homozygotes and type V.

Administration, Oral↗
PubMed2005

Vascular endothelial growth factor, c-erbB-2 and c-erbB-3 expression in colorectal adenoma and adenocarcinoma.

AIM: To analyze vascular endothelial growth factor (VEGF), c-erbB-2 and c-erbB-3 expression and to evaluate their relation to clinicopathologic parameters and pathogenesis of colorectal carcinoma. METHODS: Sections of adenoma, intramucosal carcinoma and adenocarcinoma were evaluated by immunohistochemistry in 85 malignant and 37 benign colorectal neoplasms for the expression of VEGF, c-erbB-2 and c-erbB-3 considering clinicopathological variables. RESULTS: VEGF was detected in comparable percentages of all neoplasm types while c-erbB-2 expression was detectable more frequently in adenoma than adenocarcinoma cases (65% vs 43%). Except for the correlation of c-erbB-3 expression with Dukes' staging, there was no correlation between the studied markers and grade of differentiation, Dukes' stage and localization of colorectal adenocarcinoma. c-erbB-3 expression was seen more frequently in tubular adenomas, while c-erbB-2 expression was higher in tubulovillous and villous types. These differences were not statistically significant. The presence of distant metastasis and angiolymphatic invasion were identified as independent predictors of survival. A positive correlation was found between VEGF expression and lymphatic vessel invasion and regional lymph node involvement. CONCLUSION: These results suggest that VEGF, c-erbB-2, c-erbB-3 expression does not have prognostic value in colorectal cancer. VEGF expression may be implicated in the lymph node metastasis.

Adenocarcinoma↗
PubMed2002

Maple syrup urine disease: mutation analysis in Turkish patients.

Maple syrup urine disease (MSUD), the most frequently occurring organic acidaemia in Turkey, is caused by a deficiency of the activity of branched-chain keto acid dehydrogenase enzyme (BCKAD) complex. Mutation analysis of the E1alpha, E1beta, and E2 genes of the BCKAD complex in 12 Turkish MSUD patients yielded three disease-specific mutations and a polymorphism in the E1alpha gene, none in the E1beta gene and one mutation in the E2 gene. Among them, three missense mutations (Q80E, C213Y, T106M) and the F280F polymorphism occurring in the E1alpha gene and the splice site mutation (IVS3 - 1G>A) in the E2 gene were novel. Three of the missense mutations and the splicing mutation occurred homozygously and caused classical MSUD. One patient carried the splicing mutation homozygously and the T106M mutation in the heterozygous state; this patient is the first case having simultaneously two different mutations in two different genes in the BCKAD complex. IVS3 - IG>A splicing mutation detected on the E2 gene causes deletion of the first 14 bp of exon 3 in the mutant mRNA extending between 190 and 204 nt. The deletion spans the cleavage point between mitochondrial targeting and lipoyl-bearing site of the E2 protein.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗
PubMed2001

Expression of Bcl-2 and c-ErbB-2 in colorectal neoplasia.

Several studies have been demonstrated the value of c-ErbB-2 and Bcl-2 in predicting the biological behaviour of tumors. The aim of this study was to investigate Bcl-2 and c-ErbB-2 expression in colorectal carcinomas and the correlation between their presence and other clinicopathologic parameters. Eighty-six colorectal carcinomas and 17 adenomas were stained with Bcl-2 and c-ErbB-2 immunohistochemically. Staining patterns were assessed semi-quantitatively and correlated with tumor size, Duke s classification, tumor differentiation, mucinous characteristic and anatomic locations. We detected Bcl-2 expression in 10 of 17 adenomas (58.8 %) and 31 of 86 carcinomas (36.04 %). Positive staining in normal mucosa was observed only in the compartment of cryptic cells. However neither the difference in the rates of Bcl-2 positivity in adenoma and carcinoma groups, nor the correlation with other mentioned clinicopathological parameters, were found statistically significant. Bcl-2 expression was found to be significantly high in mucinous carcinomas. Expression of c-ErbB-2 was observed in 12 of 86 (13.95 %) carcinomas. It was not detected in adenomas and normal mucosa. Although the incidence of c-ErbB-2 in nonmucinous carcinoma was higher than that of mucinous carcinoma, this was not significant. In addition we were unable to show any significant relation between c-ErbB-2 expression and other clinicopathologic features. Our result suggest that c-ErbB-2 protein expression in colorectal carcinomas, is not very frequent event. There is no correlation between c-ErbB-2 expression and malignant potential of colorectal carcinomas. Higher expressions of Bcl-2 in adenomas than carcinomas suggest us a possible role of Bcl-2 in early carcinogenesis of colon. However since we were unable to find any significant correlation between Bcl-2 expression and other parameters the impact of this gene on biological behavior is still unclear for us.

Adenoma↗
PubMed2001

Mutation analysis in Turkish patients with hereditary fructose intolerance.

Thirteen Turkish patients with hereditary fructose intolerance (HFI) were screened for the three common mutations, A149P, A174D and N334K, in the aldolase B gene that have been detected frequently in European population. We found that nine of the patients carry the A149P mutation in both alleles, which corresponds to a frequency of about 55%. Single-strand conformation analysis of all coding exons of the gene was also performed to detect unknown mutations in four patients not carrying the three common mutations. No aberrant migration patterns were observed in these patients.

Alleles↗
PubMed2001

Positive effect of low molecular weight dextrans on the early graft function.

This study evaluates the effect of the low molecular weight dextrans as a perfusion solution on early graft function of twenty living donor kidneys. Ten kidneys were perfused with +4 degrees C Ringer lactate after nephrectomy while other ten with +4 degrees C Ringer lactate + 10% Dextran. Immediate and delayed kidney function, blood creatinine, postoperative hemodialysis requirement, Doppler US and renal scintigraphy, third month graft survival and number of removed grafts were examined postoperatively as well as kidney biopsies. No statistical difference was found between the groups regarding the post-transplant ATN period. But the microscopic examinations demonstrated less damage-more function in Ringer lactate+Dextran group compared to Ringer lactate alone.

Adolescent↗
PubMed2001

HLA-DQ alleles in patients with celiac disease in Turkey.

The prevalence of the HLA-DQA1 and DQB1 alleles in 55 Turkish children with celiac disease and 50 control subjects was investigated by using an allele-specific DNA-based polymerase chain reaction-sequence-specific primer (PCR-SSP) method. The frequency of the DQA1*0501 and DQB1*02 alleles was higher in celiac patients than in controls. The DQA1B1 (*0501; *02) haplotype was present in 46 (83.6%) patients and only in 12 (24%) controls. The remaining 9 celiac patients which were negative for DQA1B1 (*0501;*02) carried the DQA1B1 (*03;*0302) haplotype. We found an excess homozygosity of the DQB1*02 allele and the DQA1B1 (*0501;*02) haplotype in the patients. No statistically significant correlation was found between the homozygosity of this haplotype or the DQB1*02 allele and an earlier onset of the disease.

Adolescent↗
PubMed2001

Effect of bilirubin in ischemia/reperfusion injury on rat small intestine.

PURPOSE: The aim of this study was to determine the effects of bilirubin in experimental small intestinal ischemia/reperfusion (I/R) injury in rats. METHODS: Thirty rats were divided into 5 groups (n = 6). In group S, saline and in group B, bilirubin, 20 mg/kg were infused via the jugular vein without an additional procedure. In groups S-IR, saline, B(1)-IR and B(2)-IR, 10 and 20 mg/kg/h of bilirubin were infused for 2 hours, respectively. In these groups, an I/R procedure was done after infusions by occluding the superior mesenteric artery for 45 minutes followed by 1 hour of reperfusion. After reperfusion, the small intestines were resected for histopathologic and malondialdehyde (MDA) assessments. Mucosal lesions were scored between 0 and 5. Malondialdehyde levels and histopathologic grades were analyzed statistically. RESULTS: Mucosal injury was severe in S-IR (grade 4 to 5), mild in B(1)-IR (grade 0 to 3) and none in B(2)-IR group (grade 0). Grades of group S-IR were higher than those of B(1)-IR and B(2)-IR statistically (P <.05). Tissue MDA levels of the S-IR group were significantly higher than those of B(1)-IR and B(2)-IR groups (U = 36, P <.05). Bilirubin levels correlated inversely with MDA levels (r = -0.94). CONCLUSIONS: Bilirubin effectively prevents intestinal I/R injury in rat. This observation is consistent with the hypotheses regarding bilirubin as an antioxidant, having a role in the body defense. J Pediatr Surg 36:1764-1767.

Animals↗
PubMed2000

Molecular analysis of 16 Turkish families with DHPR deficiency using denaturing gradient gel electrophoresis (DGGE).

Dihydropteridine reductase (DHPR) catalyses the conversion of quinonoid dihydrobiopterin (qBH2) to tetrahydrobiopterin (BH4), which serves as the obligatory cofactor for the aromatic amino acid hydroxylases. DHPR deficiency, caused by mutations in the QDPR gene, results in hyperphenylalaninemia and deficiency of various neurotransmitters in the central nervous system, with severe neurological symptoms as a consequence. We have studied, at the clinical and molecular levels, 17 patients belonging to 16 Turkish families with DHPR deficiency. The patients were detected at neonatal screening for hyperphenylalaninemia or upon the development of neurological symptoms. To identify the disease causing molecular defects, we developed a sensitive screening method that rapidly scans the entire open reading frame and all splice sites of the QDPR gene. This method combines PCR amplification and "GC-clamping" of each of the seven exonic regions of QDPR, resolution of mutations by denaturing gradient gel electrophoresis (DGGE), and identification of mutations by direct sequence analysis. A total of ten different mutations were identified, of which three are known (G23D, Y150C, R221X) and the remaining are novel (G17R, G18D, W35fs, Q66R, W90X, S97fs and G149R). Six of these mutations are missense variants, two are nonsense mutations, and two are frameshift mutations. All patients had homoallelic genotypes, which allowed the establishment of genotype-phenotype associations. Our findings suggest that DGGE is a fast and efficient method for detection of mutations in the QDPR gene, which may be useful for confirmatory DNA-based diagnosis, genetic counselling and prenatal diagnosis in DHPR deficiency.

Adolescent↗
PubMed2000

Double-blinded, randomized, placebo-controlled study to evaluate the effectiveness of sulphasalazine in preventing acute gastrointestinal complications due to radiotherapy.

BACKGROUND AND PURPOSE: Acute radiation-induced diarrhea occurs in approximately 80% of the patients receiving pelvic radiotherapy. It is caused by gastrointestinal irritation and inflammation. Eicosanoids are thought to be one of the mechanisms of this. Sulphasalazine is an inhibitor of their synthesis in the mucosa. This randomized clinical trial was undertaken to evaluate its effect in preventing acute radiation enteritis (ARE). MATERIALS AND METHODS: Prospectively, 87 patients receiving pelvic radiotherapy were randomized, in a double-blind fashion. Two tablets twice daily of sulphasalazine (500 mg) or placebo were administered orally. Patients were evaluated weekly according to diarrhea grading for the primary study endpoint and according to late effect of normal tissue-subjective objective management analytic (LENT-SOMA) criteria for the secondary endpoint during irradiation. RESULTS: Groups did not differ for age, gender, tumour site or irradiation procedure. Diarrhea occurred in 55 and 86% of the sulphasalazine and placebo groups, respectively (P=0.001). Gastrointestinal toxicity was seen in 80 and 93% of the sulphasalazine and placebo groups according to the maximum LENT-SOMA score (P=0.07). According to the maximum LENT-SOMA score between the two groups, significant differences in favor of sulphasalazine were found for each week. CONCLUSION: Sulphasalazine (2 g/day) was found to be effective in decreasing the symptoms of ARE.

Acute Disease↗