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Biomedical subjects

S Ozen

Publications and source records attributed to S Ozen.

At least 73 records · Page 4Linked to original sources
PubMed1999

The effects of caffeic acid phenethyl ester (CAPE) on spinal cord ischemia/reperfusion injury in rabbits.

OBJECTIVE: Oxygen-derived free radicals have been implicated in the pathogenesis of spinal cord neuronal injury after both trauma and ischemia-reperfusion. Caffeic acid phenethyl ester (CAPE), an active component of propolis extract, exhibits antioxidant properties. This experimental study was designed to determine the effect of CAPE on ischemia-reperfusion of spinal cord in rabbits. METHODS: Forty-one New Zealand white rabbits were used in the study. The animals undergone aortic occlusion were divided into three groups each consisting of 11 rabbits: methylprednisolone (MP), CAPE, and control. CAPE 10 micromol/kg, methyl prednisolone (MP) 30 mg/kg or similar dose saline were injected intraperitoneally before surgical intervention. Animals were subjected to 21 min of cross-clamp time. At the end of occlusion time, the clamps were removed and restoration of the blood flow was verified visually. Animals in sham group (n = 8) underwent a surgical procedure similar to the other groups but the aorta was not occluded. Neurological status was scored by assessment of hindlimb motor function deficit. RESULTS: The scores in CAPE group was different from control groups at 48 h (3.91+/-0.5 vs. 2.91+/-0.7; P = 0.0013). Spinal cord specimens were obtained to determine the tissue levels of malondialdehyde, superoxide dismutase, catalase, and histological changes. Malondialdehyde levels in control group were increased significantly when compared to sham group (124.22+/-24.36 and 41.92+/-10.08 nmol/g wet tissue, P = 0.0003). MDA levels in the CAPE group were lower than MP group and differences between the two groups were statistically significant (56.77+/-15.265 and 107.74+/-19.31 nmol/g wet tissue, P = 0.0001). We did not observe additional tissue injury in CAPE group when compared to control group. SOD and CAT activities were not concordant in all the groups. CONCLUSIONS: These results suggest that CAPE may be an available agent to protect the spinal cord from ischemia-reperfusion injury.

Animals↗
PubMed1999

Mutations in the gene encoding B1 subunit of H+-ATPase cause renal tubular acidosis with sensorineural deafness.

H+-ATPases are ubiquitous in nature; V-ATPases pump protons against an electrochemical gradient, whereas F-ATPases reverse the process, synthesizing ATP. We demonstrate here that mutations in ATP6B1, encoding the B-subunit of the apical proton pump mediating distal nephron acid secretion, cause distal renal tubular acidosis, a condition characterized by impaired renal acid secretion resulting in metabolic acidosis. Patients with ATP6B1 mutations also have sensorineural hearing loss; consistent with this finding, we demonstrate expression of ATP6B1 in cochlea and endolymphatic sac. Our data, together with the known requirement for active proton secretion to maintain proper endolymph pH, implicate ATP6B1 in endolymph pH homeostasis and in normal auditory function. ATP6B1 is the first member of the H+-ATPase gene family in which mutations are shown to cause human disease.

Acidosis, Renal Tubular↗
PubMed1999

Localization of a gene for autosomal recessive distal renal tubular acidosis with normal hearing (rdRTA2) to 7q33-34.

Failure of distal nephrons to excrete excess acid results in the "distal renal tubular acidoses" (dRTA). Early childhood features of autosomal recessive dRTA include severe metabolic acidosis with inappropriately alkaline urine, poor growth, rickets, and renal calcification. Progressive bilateral sensorineural hearing loss (SNHL) is evident in approximately one-third of patients. We have recently identified mutations in ATP6B1, encoding the B-subunit of the collecting-duct apical proton pump, as a cause of recessive dRTA with SNHL. We now report the results of genetic analysis of 13 kindreds with recessive dRTA and normal hearing. Analysis of linkage and molecular examination of ATP6B1 indicated that mutation in ATP6B1 rarely, if ever, accounts for this phenotype, prompting a genomewide linkage search for loci underlying this trait. The results strongly supported linkage with locus heterogeneity to a segment of 7q33-34, yielding a maximum multipoint LOD score of 8.84 with 68% of kindreds linked. The LOD-3 support interval defines a 14-cM region flanked by D7S500 and D7S688. That 4 of these 13 kindreds do not support linkage to rdRTA2 and ATP6B1 implies the existence of at least one additional dRTA locus. These findings establish that genes causing recessive dRTA with normal and impaired hearing are different, and they identify, at 7q33-34, a new locus, rdRTA2, for recessive dRTA with normal hearing.

Acidosis, Renal Tubular↗
PubMed1999

Vasculopathy, Behçet's syndrome, and familial Mediterranean fever.

Within the past year information has accumulated on the role of infections in the pathogenesis of vasculitis. Superantigens play an important role in the stimulation of the immune system. Behçet's syndrome is a vasculitis that affects children as well as adults. Recently published childhood studies highlight the importance of family history and geographic differences in this disease. Familial Mediterranean fever is a genetic disease manifesting frequently in children. Studies on the function of the mutated protein pyrin in this disease are in progress. Some researchers have proposed that pyrin is an anti-inflammatory protein. Understanding its mode of action will help us understand more of the general inflammatory pathway.

Behcet Syndrome↗
PubMed1998

Mutations in the chloride-bicarbonate exchanger gene AE1 cause autosomal dominant but not autosomal recessive distal renal tubular acidosis.

Primary distal renal tubular acidosis (dRTA) is characterized by reduced ability to acidify urine, variable hyperchloremic hypokalemic metabolic acidosis, nephrocalcinosis, and nephrolithiasis. Kindreds showing either autosomal dominant or recessive transmission are described. Mutations in the chloride-bicarbonate exchanger AE1 have recently been reported in four autosomal dominant dRTA kindreds, three of these altering codon Arg589. We have screened 26 kindreds with primary dRTA for mutations in AE1. Inheritance was autosomal recessive in seventeen kindreds, autosomal dominant in one, and uncertain due to unknown parental phenotype or sporadic disease in eight kindreds. No mutations in AE1 were detected in any of the autosomal recessive kindreds, and analysis of linkage showed no evidence of linkage of recessive dRTA to AE1. In contrast, heterozygous mutations in AE1 were identified in the one known dominant dRTA kindred, in one sporadic case, and one kindred with two affected brothers. In the dominant kindred, the mutation Arg-589/Ser cosegregated with dRTA in the extended pedigree. An Arg-589/His mutation in the sporadic case proved to be a de novo mutation. In the third kindred, affected brothers both have an intragenic 13-bp duplication resulting in deletion of the last 11 amino acids of AE1. These mutations were not detected in 80 alleles from unrelated normal individuals. These findings underscore the key role of Arg-589 and the C terminus in normal AE1 function, and indicate that while mutations in AE1 cause autosomal dominant dRTA, defects in this gene are not responsible for recessive disease.

Acidosis, Renal Tubular↗
PubMed1998

Antineutrophil cytoplasmic antibodies in childhood systemic lupus erythematosus.

We aimed to evaluate the presence of peripheral antineutrophil cytoplasmic antibodies (p-ANCA) and cytoplasmic antineutrophil cytoplasmic antibodies (c-ANCA) in children with SLE and to correlate its association of laboratory findings. Twenty-one children with SLE were studied. Serum samples in patients were tested by indirect immunofluorescence (IIF) slide kit (INOVA) for c-ANCA and p-ANCA and by ELISA for myeloperoxidase (MPO-ANCA) and proteinase 3 (PR3-ANCA). All the patients but two were quiescent for lupus at the time of sampling. Sixteen of 21 patients showed positive IIF staining whereas only 5 had MPO-ANCA and 2 of nine PR3-ANCA. The data suggests that SLE may be associated p-ANCA directed against additional target antigens rather than MPO and may be implicated in the pathogenesis of SLE or may be only non-specific antibodies developed in lupus.

Adolescent↗
PubMed1998

Clinical features of Behçet's disease in children: an international collaborative study of 86 cases.

OBJECTIVES: The objective of this study was to characterize the clinical picture of Behçet's disease (BD) in children. STUDY DESIGN: A questionnaire was completed by five BD specialists from Turkey, France, Iran, or Saudi Arabia. We first reviewed 86 cases retrospectively with a specially designed computerized database and then selected 65 who met the criteria of the International Study Group for BD, which include buccal aphthosis plus at least two among recurrent genital aphthosis, eye lesions, skin lesions, and positive pathergy test. The remaining 21 patients, who had features suggestive of BD but did not fulfill the international criteria, were analyzed separately and then compared with the other 65 patients. RESULTS: BD affected boys and girls equally. The clinical picture frequently included mucocutaneous lesions. Uveitis was less frequent than in adults but carried a poor prognosis, especially in male patients (p < 0.001). The mortality rate (3%) was related to large vessel involvement. Familial cases were particularly frequent (15%). Erythema nodosum and skin hypersensitivity were common in Turkish patients, whereas neuro-BD was more frequent in French and Saudi Arabian patients. Patients who did not fulfill the international criteria had significantly less genital aphthosis (p < 0.01), less skin lesions or hypersensitivity (p < 0.01), and less uveitis (p < 0.01). CONCLUSION: BD in children is similar to BD in adults. The high frequency of familial cases calls for further investigation of the immunogenetic factors that may favor early expression of the disease.

Adolescent↗
PubMed1998

Giant vascular eccrine spiradenoma.

A 60-year-old man suffering from cardiac insufficiency consulted the Dermatology Department, Inönü University Turgut Ozal Medical Center, because of a bleeding tumor on his right hypochondrium. The tumor had begun as a small nodule approximately 5 years before, and had grown slowly with time. A small, superficial ulcer had appeared on the lesion approximately 6 months previously, and slight bleeding had occasionally occurred. The patient had no pain and no other complaint except bleeding. Dermatologic examination revealed a violaceous, ulcerated, and bleeding tumoral lesion below the mid-portion of the right costochondral line. The tumor was a non-tender, hemispheric mass, approximately 3-4 cm in size, adherent to the epidermis, but movable on the underlying tissue. An incisional biopsy was performed with diagnoses of dermatofibrosarcoma protuberans and desmoid tumor. Histopathologic examination revealed prominent blood-filled vascular spaces and clearly delimited cords, showing two types of cell. The vascular spaces contained a periodic acid-Schiff (PAS)-positive, granular, eosinophilic material. There was no malignant transformation. The lesion was totally excised and primarily sutured.

Adenoma, Sweat Gland↗
PubMed1998

Nutritional assessment of children on haemodialysis: value of IGF-I, TNF-alpha and IL-1beta.

BACKGROUND: Protein-energy malnutrition (PEM) is associated with increased morbidity and mortality in haemodialysis (HD) patients. Insulin-like growth factor I (IGF-I) has proved to be a sensitive marker of malnutrition, while interleukin-1 (IL-1beta) and tumour necrosis factor (TNF) have been found to be raised in catabolic states. METHODS: We have investigated the nutritional status of 17 chronic renal failure (CRF) paediatric patients (8 boys, 9 girls) on maintenance HD. Eight predialysis CRF children (5 boys and 3 girls; mean creatinine 5.1+/-3.2 mg/dl) and 10 healthy children served as control groups. PEM was defined according to anthropometric measurements (triceps skinfold thickness (TST), mid-arm circumference (MAC), and mid-arm muscle circumference (MAMC)). These were correlated with serum IGF-I, IL-1, TNF-alpha, transferrin, and albumin (all sampled before the HD session). RESULTS: In the HD group, TST was reduced in 41.2% of the patients, whereas MAC and MAMC were reduced in 82.4 and 76.5% respectively. TST was depleted in only one of the predialysis CRF children. The degree of reduction in MAC and MAMC were 62.5 and 62.5% respectively. Median serum IGF-I level was decreased in both HD and predialysis CRF patients (205.1 interquartile range (IQR) 194.4 microg/l and 258.8 IQR 155.0 microg/l respectively) compared to the healthy children (418.0 IQR 310.5 microg/l) (P=0.0009 and P=0.01 respectively). Within the HD group, IGF-I levels were lower in patients with malnutrition defined according to TST (145.0 IQR 125.5 microg/l) compared to children with normal TST (301.2 IQR 218.8 microg/l) (P=0.05). IGF-I levels of the HD patients with malnutrition according to TST was also lower than the predialysis CRF patients and healthy children (P=0.04 and P=0.002 respectively). Serum IL-1beta was undetectable in all groups. Median serum TNF-alpha levels were higher in HD and predialysis CRF patients compared to healthy children, albeit statistically insignificant. There was no correlation between TNF-alpha, transferrin or albumin and anthropometric parameters. CONCLUSIONS: Our results support the high prevalence of malnutrition in CRF children, which becomes more pronounced when treatment by HD is initiated. We suggest that determination of IGF-I levels in childhood HD patients in conjunction with anthropometric measurements is useful for identification of malnutrition. We have not been able to demonstrate the catabolic effects of cytokines on this state of protein energy malnutrition.

Adolescent↗
PubMed1998

Three cases of verrucous carcinoma.

Verrucous carcinoma of the skin and mucosa is an uncommon clinicopathological variant of low grade squamous cell carcinoma. Here, we present three different clinical types of verrucous carcinoma. The first patient presented with an anogenital verrucous carcinoma, also known as Buschke-Loewenstein tumour. The second patient had verrucous carcinoma of the heel with endophytic growth (i.e. epithelioma cuniculatum) and the third patient had gluteal verrucous carcinoma with a cauliflower-like appearance. Clinically, the lesion of the first patient best resembled giant condyloma accuminatum without any prominent verrucous component, whereas the second patient showed a big deep ulcer on the heel. None of the patients had metastasis. The diagnosis was confirmed with biopsy and total excision was performed in all cases. Although the cases have different clinical presentations in different locations, we think that they should be considered as a single entity; that is, verrucous carcinoma.

Adult↗
PubMed1998

Prevalence of juvenile chronic arthritis and familial Mediterranean fever in Turkey: a field study.

OBJECTIVE: To investigate the prevalence of juvenile chronic arthritis (JCA), familial Mediterranean fever (FMF), and Behçet's disease in Turkish children through a field survey. METHODS: The field survey was based on cluster centering with 2 level strata. A total of 46,813 children were screened. For the diagnosis of chronic arthritis and Behçet's previously suggested criteria were used. We have developed criteria for the diagnosis of probable FMF. Children previously diagnosed to have these diseases were also defined and included. RESULTS: JCA was found in 6.4/10,000. 2.8/10,000 children were previously diagnosed as FMF (minimum phenotype frequency). Together with the probable diagnosis of FMF, the prevalence increased to 9.3/10,000. The findings were also compared with those of our center. None of the 46,813 children had Behçet's disease. CONCLUSION: The prevalence of chronic arthritis is similar to the other childhood populations reported. However, FMF has a very high prevalence.

Abdominal Pain↗
PubMed1997

Myelodysplastic features in juvenile rheumatoid arthritis.

We have attempted to investigate the dysplastic changes in the hematopoietic system associated with juvenile rheumatoid arthritis (JRA) and its relation to disease activity. The peripheral blood smear and bone marrow aspiration samples of 17 JRA patients were investigated and correlations with laboratory parameters of disease activity sought. The age range was 6-16 years and the duration of disease 1.5-108 months. Abnormal finding of the peripheral smear and bone marrow were scored separately. The score of pathological peripheral blood findings correlated significantly with CRP and ferritin (both P <0.05). In the bone marrow specimens marked changes were noted in the myeloid, erythropoietic, and megakaryopoietic series; however, the score of pathological findings did not correlate with laboratory parameters of disease activity (P > 0.05). We suggest that JRA is associated with marked myelodysplastic changes, also manifested in the peripheral blood smear; these changes may well be the consequence of the inflammatory milieu, including cytokines, during active disease.

Adolescent↗
PubMed1997

Application of the 'Apt test' in prenatal diagnosis to evaluate the fetal origin of blood obtained by cordocentesis: results of 30 pregnancies.

This study aimed to set up a practical lab-side approach to discriminate fetal from maternal blood in samples obtained by cordocentesis. To determine the fetal origin of the blood, a modified Apt test was applied to 30 cases of prenatal diagnosis. A change of colour of the fetal and adult blood during the procedure was the hallmark to assess fetal origin. At the end of 60 s of the test, fetal blood yielded a pink colour whereas adult blood was dark green-brown. The test was repeated in mixtures of fetal and adult blood. The results suggest that the modified Apt test is a practical, quick, inexpensive, and efficient test to determine the origin of blood samples obtained by cordocentesis. However, it should be kept in mind that samples containing a mixture of both fetal and adult blood could also yield a fetal blood reaction. When maternal contamination is suspected, we propose that at least 30 metaphases from different slides should be counted. This could yield fetal as well as maternal chromosomes.

Cordocentesis↗
PubMed1997

Interleukin-1, -6, and -8 levels in juvenile chronic arthritis.

The immunoinflammatory pathogenesis of juvenile chronic arthritis (JCA) involves the activation of many pathways including various cytokines. We have evaluated the levels of interleukin(IL)-1, IL-6 and IL-8 in 29 JCA patients. The age range was 1-16 with a mean of 10.1. A disease activity score was developed on the basis of: 1. constitutional symptoms and/or morning stiffness, 2. presence of joint swelling, 3.warmth, 4.limited range of motion, and 5.joint pain. This score correlated very significantly with laboratory disease activity markers such as erythrocyte sedimentation rate (ESR) and CRP (both p = 0.006) and also correlated with IL-1 and IL-6 levels. The levels of IL-1 decreased in four of the five patients with improved disease activity. IL-6 but not IL-1 correlated significantly with the number of inflamed joints (p = 0.013); IL-6 also strongly correlated with rheumatoid factor supporting this cytokine's role in B cell induction (p = 0). Haemoglobin values correlated negatively with the activity index, ESR, CRP, IL-1 and IL-6. IL-8 did not correlate with disease activity markers. In the systemic patients all cytokines tended to be higher. Our data suggest that interleukins 1 and 6 are effective in the pathogenesis of JCA. Whether cytokines may be used for monitoring therapy may be clarified with further studies.

Adolescent↗