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Biomedical subjects

A Polat

Publications and source records attributed to A Polat.

30 records · Page 2Linked to original sources
PubMed1999

Urinary zinc excretion and zinc status of patients with beta-thalassemia major.

In this study, zinc status and urinary zinc excretion with and without desferrioxamine (DFO) infusion and the relationship between urinary zinc excretion and renal tubular dysfunction in thalassemia major (TM) patients were investigated. Forty TM patients were given four DFO infusions on alternate days over a 1-wk period prior to the transfusion. On each day that DFO was given, a 24-h urine collection initiated. DFO was omitted for 1-wk before the following transfusion and during the period four 24-h urine collections were performed. Twenty healthy children provided 24-h urine collection as controls. Blood samples were taken on each of two consecutive transfusion days of the patients and from the controls. Urinary zinc excretion was measured and plasma and red blood cell (RBC) zinc analysis were performed by inductively coupled plasma-atomic emission spectrophotometry. Urinary N-acetyl-beta-D-glucosaminidase (NAG) activity and creatinine were determined in morning urine specimens. The mean plasma zinc concentration was significantly lower in the patients not given DFO compared to the values of the patients given DFO and the control group. The mean RBC zinc concentration (micromol/g Hb) in the patients (with and without DFO) and the control group were similar. Urinary zinc excretion was significantly higher in the patients receiving DFO compared to the control group, whereas urinary zinc excretion in the patients not given DFO was not different from the controls. Urinary NAG indices (U/g Cr) were significantly higher in the patients compared to controls. Urinary zinc excretion was correlated with the urinary NAG indices.

Adolescent↗
PubMed1998

Fine needle aspiration (FNA) cytology in tuberculous lymphadenitis.

UNLABELLED: Sixty-three lymph node aspirates were screened and 32 aspirates revealing granulomatous lymphadenitis with or without caseation necrosis were re-evaluated. The most characteristic morphological features among these cases were epithelioid cell clusters with or without caseation necrosis. When clusters were thick, careful observation of the periphery of the clusters helped to find epithelioid cells. Caseation necrosis revealed a typical macroscopic and microscopic appearance. Ziehl-Neelsen staining was negative in all smears and histological sections. Polymerase chain reaction (PCR) amplification technique was applied to 23 of the cases in which the cytological diagnoses were consistent with tuberculosis. Mycobacterium tuberculosis was demonstrated in 19 (82.60%) cases. IN CONCLUSION: (i) it is necessary to perform several aspirations from different sites of the enlarged lymph node; (ii) the diagnosis of 'granulomatous lymphadenitis, consistent with tuberculosis' can be given, even though the acid-fast stains are negative; (iii) additional techniques such as PCR give supportive information; (iv) an open biopsy is recommended if there is a discrepancy with the clinical impression.

Adolescent↗
PubMed1998

Inhibitor development and substitution therapy in a developing country: Turkey.

Prevalence of inhibitor in developing countries, such as Turkey, where fresh frozen plasma (FFP) is still in use due to high cost of concentrates, is unknown. To determine the frequency of inhibitors in Turkish haemophiliacs exposed to blood products, 53 haemophilia A patients (age range 1-20; median: 11 years) and 12 haemophilia B patients (age range 3-20; median: 10 years), were evaluated; 31 haemophilia A patients (23 severe) received plasma-derived concentrates and 22 patients (10 severe) only FFP. No haemophilia B patients developed inhibitor, compared with seven of 53 (13%) haemophilia A patients, all with a severe defect (7/33; 21%) and treated with concentrates (7/23; 30%), whereas severe patients treated with FFP showed a lower risk to develop inhibitors (0/10, P = 0.07). Inhibitors were detected after 8-125 exposure days (median: 52). Intermediate-purity concentrates and pasteurization seemed to be linked with a higher risk of inhibitor compared to high-purity concentrates and solvent-detergent inactivation for seven patients with inhibitor. In four of seven inhibitor patients low-dose concentrate was administered at 25 IU kg-1 twice weekly and inhibitor disappeared in 1-4 months. This regimen might be recommended for immune tolerance in developing countries for its lower cost.

Adolescent↗
PubMedDate not supplied

Protective effect of chelerythrine on gentamicin-induced nephrotoxicity.

Despite their beneficial effects, aminoglycosides including gentamicin (GEN) have considerable nephrotoxic side-effects. The toxicity of GEN at the level of the kidney seems to relate to the generation of reactive oxygen species (ROS). ROS have been reported to be involved in the activation of protein kinase C (PKC). The unique structural aspects of PKC cause it to function as a sensor for oxidative stress. It seems likely that the increased NAD(P)H oxidase-derived superoxide (O2) production is at least in part mediated by PKC. We investigated the effects of chelerythrine, a commonly used PKC inhibitor, on GEN-induced changes of renal malondialdehyde (MDA), nitric oxide (NO) generation, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities, glutathione (GSH) content, and serum creatinine (Cr), blood urea nitrogen (BUN) levels. Morphological changes in the kidney were also examined. GEN administration to control rats increased MDA and NO generation but decreased CAT, SOD and GSH-Px activities, and GSH content. Chelerythrine administration with GEN caused significantly decreased MDA, NO generation and increased CAT, SOD and GSH-Px activities, and GSH content when compared with GEN alone. Chelerythrine also significantly decreased serum Cr and BUN levels. Morphological changes in the kidney including tubular necrosis were evaluated qualitatively. Both biochemical findings and histopathological evidence showed that administration of chelerythrine reduced the GEN-induced kidney damage. We propose that chelerythrine acts in the kidney as a potent scavenger of free radicals to prevent the toxic effects of GEN via the inhibition of a PKC pathway.

Alkaloids↗
PubMedDate not supplied

Mast cells and fibrosis on testicular biopsies in male infertility.

Testicular dysfunction correlates with increased testicular mast cells. Mast cells can activate fibroblasts and promote collagen synthesis. The aim of the study was to examine testicular mast cells containing tryptase, and the relationship between mast cells and different fibrosis stages of interstitium and peritubular region of testes. Testicular biopsies obtained from 33 infertile men were assigned to 2 groups: normal spermatogenesis (n = 10) and defective spermatogenesis (n = 23). Total, interstitial, and peritubular mast cells were examined immunohistochemically using antihuman tryptase. The fibrosis stage was evaluated using vimentin and alpha-smooth muscle actin. The ratio of tubules with sclerosis to total tubules was also calculated. In all cases, mast cells were mainly localized in the interstitium. The number of total mast cells was significantly higher in defective spermatogenesis than in normal spermatogenesis (p = .048). In both groups, interstitial mast cells were higher than peritubular mast cells. However, the increase in peritubular region was much higher than the increase in interstitium. Total, peritubular, and interstitial mast cell counts were not different from each other, according to the changing fibrosis stages. Total and interstitial mast cells were significantly higher in the cases with sclerosing seminiferous tubules than in the cases with no sclerosis (p = .04 and p = .024, respectively). The mast cells and the mast cell product tryptase could be involved in the etiology of defective spermatogenesis, especially whenever the last stage (tubular hyalinization and sclerosis) takes place.

Adult↗
PubMedDate not supplied

Extraovarian nongestational choriocarcinoma in a postmenopausal woman.

Primary extrauterine choriocarcinoma especially in the postmenopausal period is very rare. A 69-year-old woman, complaining of back pain, weakness, and severe fatigue with gross hematuria, was found to have paraovarian pelvic mass and underwent laparotomy. At the operation, a mass located in the right adnexal region, extending to the retroperitoneum and within the normal pathway of germ cell migration, was observed. Other peritoneal surfaces, the uterus, both the ovaries, and fallopian tubes were normal. Total abdominal hysterectomy, bilateral salphingo-oophorectomy, and excision of the right adnexal mass were performed. The histopathological report showed an extrauterine, nongonadal pure choriocarcinoma. As single-agent chemotherapy with methotrexate was ineffective, the patient received multiagent chemotherapy and responded well to the treatment. After 18 months following chemotherapy, the patient was disease free. Extraovarian nongestational choriocarcinoma can be seen within the normal pathway of germ cell migration and responds to chemotherapy-like gestational choriocarcinoma.

Aged↗
PubMedDate not supplied

Comparison of the effects of continuous and intermittent portal triad occlusion (PTO) in rats.

BACKGROUND/AIMS: It has previously been shown that prolonged ischemia of the liver had a mortal course and a method of intermittent occlusion of the hepatic pedicle was defined in order to minimize the damage to the liver. The present experimental study aimed to compare the effects of continuous and intermittent occlusion of the hepatic pedicle on the liver by measuring serum lactate, serum MDA malondialdehyde and glutathione levels and by evaluating the histologic changes in the liver tissue. METHODOLOGY: Thirty male Wistar albino rats weighing 300 +/- 50 g were divided into three groups of ten animals. Group 1 underwent a sham operation. Animals in group 2 underwent continuous portal triad occlusion (PTO group) for 30 minutes following laparotomy. The remaining ten animals in group 3 underwent intermittent occlusion consisting of 10 minutes of occlusion followed by 10 minutes of reperfusion for a total period of 30 minutes of ischemia. Blood samples were collected at the 1st and 6th postoperative hour for analytical evaluation. After sacrificing the animals, liver samples were obtained for histologic evaluation. RESULTS: The serum lactate levels were significantly higher in both portal triad occlusion groups than in the control at the 1st hour. While lactate levels also increased at the 6th hour in the continuous PTO group, it decreased to the level of control values in the intermittent PTO group. The difference between continuous and intermittent groups was also significant. Despite the unchanged malondialdehyde levels in the control group, malondialdehyde levels were significantly increased at the first and sixth hour in both PTO groups and the levels were also significantly higher than control values. Malondialdehyde levels of intermittent PTO groups at the first and sixth hour were both significantly lower than continue PTO groups. Whole blood glutathione levels were not changed in control groups with time, levels increased significantly in both PTO groups. Glutathione levels were higher than control values in both PTO groups at the first hour. While it turned to its basal value in intermittent PTO groups at the 6th hour, it was still significantly higher in the continuous PTO group. When both PTO groups were compared, glutathione levels were found to be significantly higher in the continuous group both at the first and sixth hour than in the intermittent PTO group. Histopathologic evaluation also showed that there was less damage in the intermittent PTO group than in the continuous PTO group. CONCLUSIONS: Our results show that continuous portal triad occlusion resulted in significant oxidative stress and cell damage as confirmed by increased serum lactate and blood malondialdehyde levels. The blood glutathione levels are increased due to a greater requirement in response to increased oxidative stress induced by portal triad occlusion. It is also confirmed that intermittent portal triad occlusion is safer as it causes less oxidative stress and cell damage so that its use is strongly suggested whenever portal triad occlusion is required.

Animals↗