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Biomedical subjects

M Coskun

Publications and source records attributed to M Coskun.

At least 19 recordsLinked to original sources

Humoral immune response against 38-kDa and 16-kDa mycobacterial antigens in tuberculosis.

Several ELISA tests based on mycobacterial antigens have been used for the rapid diagnosis of tuberculosis (TB), although demonstration of Mycobacterium tuberculosis in a smear or culture is the most reliable method. In the present study, the diagnostic value of 16-kDa and 38-kDa mycobacterial antigens was investigated in patients who were diagnosed with tuberculosis by clinical and/or bacteriological findings in Turkey. The PATHOZYME-TB Complex Plus commercial ELISA kit was used for measuring immunoglobulin G against 38-kDa and 16-kDa recombinant antigens. Humoral immune response was analysed in a group of 179 TB patients (143 smear-positive, 19 smear-negative, eight lymphadenitis and nine pleuritis), 15 inactive TB cases and in control groups consisting of 40 healthy volunteers and 20 subjects with pulmonary diseases other than TB. The sensitivity, specifity, positive predictive value and negative predictive value of the test were determined at 52.5%, 93.3%, 95.9% and 39.7%, respectively in TB cases. Antibodies were detected at above cut-off level in three (20%) out of 15 subjects with inactive TB. In conclusion, the ELISA test has a very good specifity and an acceptable sensitivity and positive predictive value. It is thought that it could be used in combination with other methods to increase diagnostic accuracy, especially for culture-negative tuberculosis cases, which are difficult to diagnose.

Adolescent↗

Venous complications after orthotopic liver transplantation.

We report venous complications, including portal vein and hepatic vein stenoses, that required interventional radiological treatment in three pediatric and two adult living related liver transplant recipients. Between April 2001 and April 2005, 81 liver transplantations were performed at our hospital. Sixty-two grafts were from living donors. During follow-up, three portal vein stenoses were identified in three pediatric recipients, and two hepatic vein stenoses in two adult patients. In the children, two had received left lateral segment grafts, and one had received a right lobe graft from two mothers and one father, respectively. The etiologies of liver failure were Alagille syndrome, biliary atresia, and fulminant Wilson's disease. Portal vein stenoses were identified at 8, 11, and 12 months after transplantation; all three patients underwent percutaneous transhepatic portal venous angioplasty with a success rate of 100%. The mean follow-up was 102 days; no recurrence has occurred. In contrast, hepatic venous stenoses were diagnosed in two adult recipients. One of them was a 24-year-old woman with autoimmune hepatitis and the other a 43-year-old man with cryptogenic cirrhosis. Hepatic vein stenoses were diagnosed at 3 and 4 months after transplantation. Both hepatic vein stenoses were dilated with balloon angioplasties via the transjugular route. Venous complications identified by Doppler ultrasonography were confirmed by computerized tomographic angiography. Angioplasty represents an effective and safe alternative to reconstructive surgery in the treatment of venous complications after liver transplantation.

Adolescent↗

Safety of multidetector computed tomography in calculating liver volume for living-donor liver transplantation.

Living-related liver transplantation was developed to overcome the organ shortage for both children and adults with end-stage liver disease. Because impaired liver function after resection and transplantation is caused by insufficient liver volume, the reliable volumetric assessment of the hepatic segments of potential living donors is a critical element in preoperative evaluation. In this study, we compared the results of multidetector computed tomographic (CT) volumetry with the intraoperative findings from 80 liver transplantations performed at our center. Resection borders were determined preoperatively with the aid of CT by manual delineation in which the hepatic vessels were used as guides. Resected liver grafts were weighed intraoperatively, and the calculation of their volume was based on the specific weight of 1 g/mL. Statistical analyses were performed with Pearson's correlation test; P < .05 was considered significant. The study subjects consisted of 48 women and 32 men (mean age, 35.6 +/- 9.7 years; range, 23-56 years). Forty-one donors underwent right lobectomy, 22 underwent left lobectomy, and 17 underwent left lateral segmentectomy. Manual volumetric measurement was completed within 15 minutes. No significant differences were found between the results of preoperative volumetry and the intraoperative measurement. We therefore concluded that manual CT volumetric calculation is a reliable method of calculating liver volume for living-donor liver transplantation.

Algorithms↗

TNF-alpha gene 1031 T/C polymorphism in Turkish patients with Behçet's disease.

BACKGROUND: Genetic factors that predispose individuals to Behçet's disease (BD) are considered to play an important role in development of the disease. The tumour necrosis factor (TNF)-alpha gene, which is closely linked to the HLA-B51 gene, is involved in susceptibility for BD. Recently, a polymorphism at position -1031 within the TNF-alpha promoter region was demonstrated to be responsible for susceptibility to BD in a British population. However, the functional effects of this polymorphism have not yet been determined. OBJECTIVES: To investigate the possible relation of the TNF-alpha-1031 T/C polymorphism with susceptibility to BD in a Turkish population and to determine the functional importance of this polymorphism. METHODS: Ninety-nine unrelated patients (47 women, 52 men; mean +/- SD age, 34.10 +/- 10.53 years) with BD and 103 ethnically matched healthy controls (52 males, 51 females; mean +/- SD age, 40.25 +/- 14.15) were enrolled in the study. For genotyping, polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) analysis was employed. The functional importance of TNF-alpha-1031 T/C polymorphism was determined with an enzyme-linked immunospot (ELISPOT) assay. For this purpose, mononuclear cells obtained from BD patients and controls were analysed for TNF-alpha and interferon (IFN)-gamma production. RESULTS: A significant difference was observed between BD patients and controls with respect to the allele frequency of TNF-alpha-1031C [P = 0.018, OR = 1.83, 95% confidence interval (CI) = 1.07-3.13]. When the allele frequencies were analysed according to the clinical features, the T allele in patients with positive skin pathergy test (SPT) was significantly increased when compared with those of patients without these findings (P = 0.004, OR = 2.75, 95% CI = 1.3-5.86). To demonstrate the frequency of TNF-alpha and IFN-gamma producing cells, mononuclear cells from four representative individuals of each genotype were used and the spontaneous and stimulated TNF-alpha and IFN-gamma values (spot numbers) were analysed. Compared with the control groups, a significant increase was observed in the number of cells producing TNF-alpha obtained from BD patients (P < 0.001). Moreover, the stimulation index for TNF-alpha [bacterial lipopolysaccharide (LPS) stimulated/unstimulated] was higher for the CC genotype (9 +/- 9.5) with respect to the other genotypes (TT; 1.3 +/- 0.3 and TC; 1.2 +/- 0.2). While the difference in the spontaneous IFN-gamma values between groups were not statistically significant, the stimulated IFN-gamma values were found to be significantly increased in the BD group when compared with the healthy control group (P = 0.004). CONCLUSIONS: Our results showed that, in the Turkish population the TNF-alpha-1031C allele is associated with susceptibility to BD. On the other hand, carrying the T allele may render patients more prone to developing a positive skin pathergy test. In addition, ELISPOT assays revealed that BD patients exhibited a significantly higher number of mononuclear cells producing TNF-alpha, and cells obtained from patients with a CC genotype had a stronger response to LPS stimulation. The strong IFN-gamma response upon LPS stimulation in BD patients supports the previous findings that BD is a Th1 driven disease. These findings suggest that the TNF-alpha-1031 polymorphism may have a functional effect and could explain the reason for high levels of TNF-alpha production observed in BD patients.

Adult↗

Fibroblast growth stimulation by extracts and compounds of Onosma argentatum roots.

The roots of Onosma argentatum are used traditionally in Turkey for wound healing and burns. The n-hexane-dichloromethane extract of the roots, and four shikonin derivatives (deoxyshikonin, acetyl shikonin, 3-hydroxy-isovaleryl shikonin and 5,8-O-dimethyl acetyl shikonin) isolated from the n-hexane-dichloromethane extract were investigated for their ability to stimulate the growth of human amnion fibroblasts. A range of concentrations was studied and the extract found to stimulate the growth of human amnion fibroblasts in vitro at 0.1 microg/mL whilst 5,8-O-dimethyl acetyl shikonin had the same effect at 0.05-5 microg/mL, although cytotoxicity was observed at 50 microg/mL for all samples. The extract and all the other isolated compounds showed cytotoxicity at 10 microg/mL with the extract and 3-hydroxy-isovaleryl shikonin showing cytotoxicity at 5 microg/mL. It is suggested that any wound healing effect of the roots of Onosma argentatum might be partly due to an additive effect of the shikonin derivatives present.

Amnion↗

The effect of pre-operative conventional and hyperfractionated radiotherapy schedules on wound healing and tensile strength in rats: an experimental study.

We examined the effects of pre-operative conventional and hyperfractionated radiotherapy schedules on wound healing and tensile strength in 90 female Wistar rats weighing between 182 and 240 g. The animals were randomized into three groups (n = 30 each). Group I was sham-irradiated. Group II (conventional) received 20 daily fractions of 200 cGy, to a total dose of 4000 cGy. Group III (hyperfractionated) received 40 fractions of 120 cGy, twice daily, to a total dose of 4800 cGy. Four weeks after radiotherapy, incision and primary repair with simple suturing was performed on one side of the neck. Twenty-one days after wounding, all the rats were sacrificed. Non-parametric Kruskal-Wallis and Mann-Whitney U-tests were used for the statistical analysis of wound tensile strength. The chi-squared test was used for the statistical analysis of the histopathologic findings. The hyperfractionated group had a significantly lower tensile strength than that of the control group (P = 0.03, z = -2.18). According to the histopathologic findings, fibrosis was increased significantly in the hyperfractionated group as compared to the other groups (P = 0.038, chi2 = 6.52). Hyperfractionated radiotherapy significantly reduced the wound tensile strength in the early evaluation period as compared to the control group.

Animals↗

CTLA-4 gene 49A/G polymorphism in Turkish patients with Behçet's disease.

Genetic factors predisposing individuals to Behçet's disease (BD) are considered to play important roles in the development of the disease. Patients with BD exhibit elevated levels of pro-inflammatory cytokines, and affected organs show a significant neutrophil and lymphocyte infiltration. Current evidence suggests that the activated lymphocytes contribute to neutrophil and endothelial cell activation in these patients. The cytotoxic T lymphocyte-associated antigen (CTLA)-4 molecule plays an important role in immune regulation by downregulating T-cell activation, and the CTLA-4 49A/G polymorphism in the exon 1 has been shown to be associated with a number of autoimmune diseases. In an attempt to demonstrate whether there is an association of the CTLA-4 49A/G polymorphism with BD in the Turkish population, we genotyped 59 Turkish patients and 99 healthy individuals for single-nucleotide polymorphisms. For this purpose, genomic DNA was obtained from the peripheral blood of individuals and the region of interest was amplified using PCR. Genotyping was performed using the BbvI restriction endonuclease. It was shown that the distribution of the CTLA-4 exon 1 49A/G allele and genotype frequencies did not differ between patients with BD and healthy controls. However, allele and genotype frequencies of CTLA-4 49 A and A/A were significantly higher in patients with ocular involvement compared with patients without these symptoms (90.6% vs. 65.1%, odds ratio (OR) = 9.67, P = 0.011; and 81.25% vs. 39.5%, OR = 9.56, P = 0.015, respectively). A statistically significant difference in the A allele frequency was observed in patients with erythema nodosum-like lesions (86.1% vs. 65.8%, OR = 6.24, P = 0.04). There was also an increase in A/A genotype frequency, but the difference was not statistically significant (72.2% vs. 41.5%, OR = 6.5, P = 0.068). Our data suggest that BD patients with ocular involvement and erythema nodosum-like lesions have a higher frequency of both the A allele and the A/A genotype at position 49 of exon 1 of CTLA-4. These results may also indicate that CTLA-4 is a disease-modifying rather than a susceptibility gene for BD.

Adult↗

Basal cell adenoma of the parotid gland: dynamic CT and MRI findings.

Imaging findings in basal cell adenoma (BCA) of the parotid gland have been rarely reported. We report dynamic CT and MRI findings of BCA in the parotid gland in a 78-year-old woman. Dynamic CT study demonstrated strong multinodular contrast enhancement in the early phase which decreased gradually in the later phases. The mass was isointense on T(1) weighted and hyperintense on T(2) weighted MR images with a central haemorrhagic-necrotic component. The microscopic findings were consistent with membranous type BCA.

Adenoma↗

Land use change analysis of Beykoz-Istanbul by means of satellite images and GIS.

Management and planning of the natural environment requires spatially accurate and timely information on land use patterns. With repetitive satellite coverage, the rapid evolution of computer technology and the integration of satellite and spatial data, the development of land use applications have become ubiquitous. The integration of Remote Sensing (RS) and Geographic Information Systems (GIS) has been widely applied and recognized as a powerful and effective tool in detecting land use change in urban areas. This paper presents the land use change analysis of the Beykoz region, which is the second largest administrative district of Istanbul. Land use changes and their impacts are monitored using Landsat (MSS - TM) and Spot 5 satellite data in the period of 1975-2001. The independent classification of each satellite image was used as a change analysis method and the resulting images were analyzed with GIS techniques. The results showed that forest area of Beykoz decreased from 80.55% to 70.5% between 1975 and 1984 and during the 1984-2001 periods, the forested area decreased from 70.5% to 68.86% and the urban growth rate was 4.65%.

Conservation of Natural Resources↗

Tubo-ovarian abscess in a sexually inactive adolescent patient.

Tubo-ovarian abscess as a complication of acute salpingitis or salpingo-oophoritis is very uncommon in pre-menarchal and/or sexually inactive girls. It is generally the result of a blood-borne or genitourinary infection. Early diagnosis and treatment are essential to prevent future sequelae causing infertility. Laparoscopic surgery which minimises postoperative complications should be the first option in the treatment of TOA.

Abscess↗

The Arg753GLn polymorphism of the human toll-like receptor 2 gene in tuberculosis disease.

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.

Adult↗

Percutaneous sclerotherapy of a giant benign renal cyst with alcohol.

We report a case of giant, benign renal cyst that was treated with percutaneous aspiration and sclerotherapy using 95% alcohol. A seven French catheter was inserted into the cyst under ultrasonographic and fluoroscopic guidance, and was then left in place to drain the cyst contents. Approximately 4 l of fluid was drained the first day. The following day, a gravity sinogram was obtained, which showed there were no connections between the cyst and the collecting system. The alcohol treatment involved repeated injections of decreasing amounts of alcohol, with volumes selected in accordance with follow-up sinograms. The patient's symptoms resolved and cyst drainage stopped after 3 successive days of therapy. Totally 600 ml alcohol has given. Follow-up ultrasound (US) and computed tomography (CT) studies showed no recurrent disease; with only a small remnant of the cyst wall. We encountered no major complications during follow-up.

Ethanol↗

Catheter-directed thrombolysis with transjugular access in portal vein thrombosis secondary to pancreatitis.

A case of portal vein thrombosis (PVT) secondary to pancreatitis is presented. Patient was treated with catheter-directed thrombolysis using urokinase solution. Because the percutaneous transhepatic approach is associated with higher risk of hemorrhage we used the catheter-directed thrombolysis via the transjugular intrahepatic access to restore the patency of the thrombosed portal vein. This case shows that catheter-directed thrombolysis with transjugular approach can be effectively used in the treatment of PVT.

Catheterization↗

Successful heterotopic segmental liver transplantation from a live donor to a patient with Alagille syndrome.

Alagille syndrome is characterized by a paucity of bile ducts in the liver. The syndrome is associated with some or all the features of chronic cholestasis, cardiac disease, skeletal abnormalities, ocular defects and a distinctive facial appearance. The most common finding is chronic cholestasis, which causes intractable pruritus, xanthoma, deficiency of certain metabolic nutrients and growth retardation. Cardiac abnormalities are the most common cause of death in these patients. It is unusual to see the clinical picture of hepatic failure resulting in cirrhosis and requiring transplantation, but liver transplantation is indicated in Alagille syndrome patients who have chronic cholestasis. If the disease is diagnosed in childhood, transplantation can improve significantly the patient's prognosis and the quality of life. In recent years, auxiliary liver transplantation has gained popularity for treating both acute and chronic liver disease. Heterotopic segmental liver transplantation is an alternative treatment modality for patients who do not require native liver removal. Individuals with Alagille syndrome are good candidates for this type of treatment. J Pediatr Surg 36:667-671.

Adolescent↗

Interleukin-1beta, interleukin-1 receptor antagonist levels in patients with subacute sclerosing panencephalitis and the effects of different treatment protocols.

Subacute sclerosing panencephalitis is a rare progressive inflammatory disease of the central nervous system caused by a persistent aberrant measles virus infection. Cytokines are polypeptides that regulate immune responses and inflammatory reactions. Interleukin-1beta has been implicated as a central mediator of tissue damage and destruction in a number of central nervous system diseases. Interleukin-1 receptor antagonist could function as an important anti-inflammatory cytokine. We studied interleukin-1beta and interleukin-1 receptor antagonist levels in the cerebrospinal fluids of patients with subacute sclerosing panencephalitis and evaluated the effects of different treatment protocols on these cytokines. Interleukin-1beta and interleukin-1 receptor antagonist levels were measured in 15 patients who had a recent diagnosis of subacute sclerosing panencephalitis (group 1), 6 patients who had been treated with isoprinosine (group 2), 5 patients with intraventricular interferon-alpha (group 3), and 6 patients with interferon-beta (group 4). The results were compared within the groups and also with the results of 10 patients with other neurologic disease (group 5). The interleukin-1beta concentrations in cerebrospinal fluid and sera were all below the detection limits (3.9 pg/mL). Interleukin-1 receptor antagonist levels were not statistically different, except for the group treated with intraventricular interferon-alpha. Interleukin-1 receptor antagonist levels were 170 +/- 52, 175 +/- 58, 1605 +/- 518, 77.5 +/- 24, and 108 +/- 18 pg/mL in groups 1 to 5, respectively. Interleukin-1 receptor antagonist levels and cerebrospinal fluid serum ratios were significantly increased during interferon-alpha treatment. In conclusion, interleukin-1 and interleukin-1 receptor antagonist levels were not elevated in the patients with subacute sclerosing panencephalitis. The only treatment protocol that affects interleukin-1 receptor antagonist levels in cerebrospinal fluid was intraventricular interferon-alpha. Further studies on higher numbers of patients may better document the immunologic status of patients with subacute sclerosing panencephalitis and the effects of different treatment modes.

Administration, Oral↗

Chondromyxoid fibroma of the temporal bone: CT and MRI findings.

We present the case of a 44-year-old woman with chondromyxoid fibroma of temporal bone origin. Since this is the least common bone tumor of cartilaginous origin, it is highly unusual to find this tumor in the skull. In fact, the literature describes 18 cases of this form of neoplasia arising in the skull, only 4 of these having originated in the temporal bone. To date, the radiological features of these tumors, and especially features detected using the latest imaging modalities, have not been described in detail. This report is unique in that it is the first to present a case of chondromyxoid fibroma of the temporal bone accompanied by detailed CT and MRI findings.

Adult↗