PubMed Health⌕ Search

Biomedical subjects

S Sahin

Publications and source records attributed to S Sahin.

At least 19 recordsLinked to original sources

Natural radioactivity measurement in pumice samples used raw materials in Turkey.

The activity concentrations of 232Th, 226Ra, and 40K in different pumice samples have been determined by high-resolution gamma-ray spectrometry using a 110% HpGe detector. The radium equivalent activities (Raeq), external hazard index (Hex), and internal hazard index (Hin) associated with the natural radionuclides and representative level index (Igamma r) are calculated to assess the radiation hazard of the natural radioactivity in the pumice samples. The mean values of the measured radioactivity concentrations of 232Th, 226Ra, and 40K for pumice samples from the region of lakes (ROL) are 232.4+/-8.0, 196.9+/-7.8, and 1325.8+/-20.4 Bqkg(-1) and for pumice samples from Cukurova region (CR) 16.3+/-4.0, 16.1+/-4.9, and 479.7+/-170.4 Bqkg(-1), respectively. The calculated Raeq values vary from 435.9+/-12.5 to 883.6+/-41.5 Bqkg(-1) with a mean of 630.9+/-20.2 Bqkg(-1) for the ROL samples and from 49.7+/-3.3 to 101.9+/-7.2 Bqkg(-1) with a mean of 76.3+/-23.7 Bqkg(-1) for the CR samples. For the ROL samples, Raeq are above the limit of 370 Bqkg(-1), equivalent to external gamma dose of 1.5 mSv yr(-1), recommended for the safe use of construction materials by NEA-OECD, while for the CR samples, Raeq values are lower than the limit.

Environmental Pollutants↗

Utilization of elderly donors in living related kidney transplantation.

Kidney transplantation has become the treatment of choice for end-stage renal disease. However, its application is limited due to inadequate organ supply, mainly because many dialysis patients do not have suitable living donors. The increasing discrepancy between organ supply and demand has forced many transplant centers to consider using organs procured from marginal donors. The aim of this study was to investigate whether utilization of kidneys from living related elderly donors is safe for the recipients in the long term. We analyzed the clinical results of 296 consecutive recipients of living related renal transplants, among whom 44 recipients received kidneys from donors over 60 years of age. By the end of 12 months, the mean serum creatinine level of the recipients who were transplanted from the older donors was higher (1.55 +/- 0.45 mg/dL) than that from other donors (1.21 +/- 0.3 mg/dL), but the difference was not significant (P = .08). In the long term (60 months), the graft function was similar (1.88 +/- 0.55 vs 1.52 +/- 0.38) for both groups. The similarity in outcomes of ideal versus older donors as shown less in the present series has encouraged us to utilize elderly living donors. We concluded that transplantations performed from the elderly donors yielded similar results to those of conventional donors. The long waiting list for transplantation, the treatment of choice for end-stage renal disease, should encourage us to be more flexible about donor selection.

Adult↗

Lipid profile in chronic allograft nephropathy.

Chronic allograft nephropathy (CAN) represents the cumulative and incremental damage to nephrons by time-dependent immunologic and nonimmunologic causes. Hyperlipidemia is one nonimmunologic mechanism that promotes injury and poor function in a renal transplant. The aim of our study was to determine the effect of lipid profiles on CAN among renal transplant recipients. We retrospectively evaluated 53 renal transplant recipients who were classified according to the presence of CAN: CAN+ = 28 (18 males, 10 females) constituted the study group, whereas those with stable graft function CAN- = 25 (14 males, 11 females) were the control group. Biochemical parameters included serum urea, creatinine, total cholesterol, triglyceride, HDL cholesterol, LDL cholesterol, apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), lipoprotein (a), homocysteine, and high-sensitive CRP (hs CRP). Angiotensin-converting enzyme inhibitor (ACEI) and/or angiotensin receptor blocker (ARB) use was significantly greater among the CAN+ group compared with the controls (P = .02, P = .04). Also, higher serum creatinine levels were observed in the CAN+ group (1.49 vs 1.22 mg/dL, P = .002), whereas serum levels of total cholesterol, triglyceride, hs CRP, and albumin were similar in both groups. The levels of ApoA1, ApoB, and lipoprotein (a) were similar, whereas the LDL/HDL cholesterol ratio and homocysteine levels were significantly higher in the CAN+ group (P = .04, P = .04). In conclusion, the LDL/HDL ratio may have a positive impact on CAN and may be used as a parameter during patient follow-up.

Adult↗

Impact of hepatitis C virus infection on patient and graft survival in kidney transplantation.

Hepatitis C virus (HCV) infection is the main cause of chronic liver disease after renal transplantation, which represents a risk factor for graft loss and patient death. Hepatitis C (+) kidney transplant candidates who remain on the waiting list show a greater risk of mortality than those who are transplanted, a risk that escalates with time. The aim of this study was to examine the impact of HCV infection on patient and allograft survival in our transplant population. Among 90 renal transplant patients transplanted between 1991 and 2002 who were retrospectively analyzed, 45 were HCV-positive and 45 HCV-negative by serology. All positive patients had shown positive HCV antibody and/or positive HCV RNA. The mean ages of the patients were 36.2 +/- 9 years among the HCV (+) and 38 +/- 10 years among the HCV (-) patients (P = .31). Eighteen HCV (+) patients and 14 HCV (-) patients received their grafts from deceased donors. The immunosuppressive protocols were similar in both groups. The number of acute rejection episodes were 13 (30%) in HCV (+) and 6 (13%) in the HCV (-) group (P = .006). Diabetes mellitus developed in 10 (23%) HCV (+) and 7 (16%) HCV (-) patients (P = .04). Cytomegalovirus disease occurred in 5 (16%) HCV (+) and 2 (6%) HCV (-) patients (P = .32). The mean serum creatinine was 1.85 +/- 1.1 mg/dL in HCV (+) and 1.8 +/- 1 mg/dL in HCV (-) group (P = .82). The mean graft survivals were 97.1 +/- 52 months in the HCV (+) and 81.1 +/- 37 months in the HCV (-) group (P = .04). Seven HCV (+) patients (16%) and three HCV (-) patients (6%) lost their grafts (P = .04). Advanced cirrhosis developed in three HCV (+) patients (6%). One patient died in the HCV (+) group. Patient survivals were 98% in the HCV (+) and 100% in the HCV (-) cohorts. In this study, the rate of graft loss was higher in HCV (+) patients, whereas the patient survival was similar.

Adult↗

Tuberculin positivity: A serious problem before transplantation in Turkey.

Chronic renal failure (CRF) patients are at increased risk of tuberculosis. Detecting latent tuberculosis infection is essential before transplantation. The tuberculin skin test is the only validated method for the diagnosis of latent tuberculosis infection and for screening for hypersensitivity. The aim of this study was to assess the tuberculin test status (5 Todd units tuberculin) of 164 asymptomatic transplant candidates and correlate it with anamnestic data and laboratory values of patients awaiting transplantation. Skin test positivity was higher among older age subjects (r = .294, P = .0001). The cumulative prevalence rates of tuberculin positivity and anergy were 42.1% (69 patients) and 43.3% (71 patients), respectively. Only 14.5% of the positive patients had a previous tbc history; 15.9% had a family history of tbc. Among peritoneal dialysis (PD) patients, the rate of anergic skin tests was higher, while positivity was higher among patients who were preparing for preemptive renal transplantation (P = .009). In conclusion, there was a high prevalence of tuberculin positivity and anergy among asymptomatic pretransplant CRF patients. CRF patients who are awaiting transplantation especially should meet evaluations for previous tbc anamnesis and family history. Elderly subjects showed a higher risk for purified protein derivate positivity.

Adult↗

Proteinuria after conversion to sirolimus in renal transplant recipients.

Sirolimus (SRL) is a new, potent immunosuppressive agent. More recently, proteinuria has been reported as a consequence of sirolimus therapy, although the mechanism has remained unclear. We retrospectively examined the records of 25 renal transplant patients, who developed or displayed increased proteinuria after SRL conversion. The patient cohort (14 men, 11 women) was treated with SRL as conversion therapy, due to chronic allograft nephropathy (CAN) (n = 15) neoplasia (n = 8); Kaposi's sarcoma, Four skin cancers, One intestinal tumors, One renal cell carsinom) or BK virus nephropathy (n = 2). SRL was started at a mean of 78 +/- 42 (15 to 163) months after transplantation. Mean follow-up on SRL therapy was 20 +/- 12 (6 to 43) months. Proteinuria increased from 0.445 (0 to 1.5) g/d before conversion to 3.2 g/dL (0.2 to 12) after conversion (P = 0.001). Before conversion 8 (32%) patients had no proteinuria, whereas afterwards all patients had proteinuria. In 28% of patients proteinuria remained unchanged, whereas it increased in 68% of patients. In 40% it increased by more than 100%. Twenty-eight percent of patients showed increased proteinuria to the nephrotic range. Biopsies performed in five patients revealed new pathological changes: One membranoproliferative glomerulopathy and interstitial nephritis. These patients showed persistently good graft function. Serum creatinine values did not change significantly: 1.98 +/- 0.8 mg/dL before SRL therapy and 2.53 +/- 1.9 mg/dL at last follow-up (P = .14). Five grafts were lost and the patients returned to dialysis. Five patients displayed CAN and Kaposi's sarcoma. Mean urinary protein of patients who returned to dialysis was 1.26 (0.5 to 3.5) g/d before and 4.7 (3 to 12) g/d after conversion (P = .01). Mean serum creatinine level before conversion was 2.21 mg/dL and thereafter, 4.93 mg/dL (P = .02). Heavy proteinuria was common after the use of SRL as rescue therapy for renal transplantation. Therefore, conversion should be considered for patients who have not developed advanced CAN and proteinuria. The possibility of de novo glomerular pathology under SRL treatment requires further investigation by renal biopsy.

Adult↗

Cutaneous mastocytosis: demographic aspects and clinical features of 55 patients.

BACKGROUND: Mastocytosis is a rare, heterogeneous group of disorder with abnormal increase of mast cells in one or more organ systems. OBJECTIVE: To evaluate the demographic and clinical features of cutaneous mastocytosis (CM). METHODS: Records of 55 patients with cutaneous mastocytosis were retrospectively analysed. RESULTS: Of the 22 females and 33 males, 80% had urticaria pigmentosa/maculopapular CM and 20% had mastocytoma. Of all cases, 81.8% had first lesions in childhood. The most common presentation was involvement of trunk together with extremities. Thirteen (23.6%) patients had history of bulla; Darier's sign was positive in 34 of 38 patients. Itching was the most common complaint, provocated by hot weather/bath. CONCLUSION: Clinical presentations of urticaria pigmentosa/maculopapular CM and mastocytoma are similar regarding gender, age of onset, age of diagnosis, and presence of Darier's sign and history of bulla. In contrast to mastocytoma, urticaria pigmentosa/maculopapular CM lesions were frequently located on trunk together with extremities.

Adolescent↗

Potential use of freeze-drying technique for estimation of tissue water content.

Desiccation and freeze-drying methods were used for the estimation of water content of various rat tissues. In the desiccation method, the tissue samples were cut into small pieces and subsequently dried at 40 degrees C to constant weight. In the freeze-drying method, the prefrozen tissue samples were freeze-dried (-50 degrees C) for 24 h. Tissue water contents obtained by the desiccation and freeze-drying methods were very similar, with no significant difference between them. Regardless of the method, the highest tissue water content was found in testes (0.841 +/- 0.010 ml/g for freeze-drying and 0.865 +/- 0.002 ml/g for desiccation); the lowest values were obtained in bone (0.254 +/- 0.007 ml/g for freeze-drying and 0.267 +/- 0.003 ml/g for desiccation). Upon correction for the water content of residual tissue blood, regardless of the drying method, significant differences were found between corrected and uncorrected tissue water values of all tissues. However, for a given method, the difference between the tissue water contents was not significant after correcting for residual blood. The water content values for all tissues (except bone) agree well with those published previously and obtained by desiccation. All these clearly suggest that the freeze-drying method can be used as an alternative to desiccation for estimation of tissue water content.

Animals↗

Abdominal aortic aneurysm surgery: retroperitoneal or transperitoneal approach?

AIM: Mortality and morbidity of abdominal aortic aneurysm surgery have decreased significantly in time and transperitoneal approach (TPA) still preserves its popularity although retroperitoneal approach (RPA) is known to cause lower incidence and shortened duration of ileus, shorter intensive care unit (ICU) and hospital stay, earlier oral intake and less patient discomfort or pain. METHODS: One hundred and fifty patients that underwent abdominal aortic aneurysm repair at our Cardiovascular Surgery Center between January, 1990 and March, 2000 were reviewed and analyzed based on the elective/emergent nature of the surgery and the type of the incision as either TPA or RPA. RESULTS: Significantly shorter mechanical ventilation (15.2+/-3.8 vs 10.1+/-2.3 hours) and nasogastric decompression periods (40.6+/-10.7 vs 9.1+/-2.2 hours), less need for intravenous fluid supplementation and shorter ICU stay (29.5+/-14.8 vs 18.6+/-1.9 hours) were observed with the retroperitoneal approach (P<0.001). Need for allogeneic blood transfusion was, similar (1.3+/-1.4 vs0.9+/-0.4, P>0.05). Analysis of mortality and morbidity revealed bleeding as the major cause of mortality for ruptured aneurysm. A similar comparison between TPA and RPA groups, however, revealed no significant difference (P>0.05). CONCLUSIONS: | Retroperitoneal approach is a reliable technique causing less fluid-electrolyte imbalance with rapid restoration of gastrointestinal physiology. It causes less discomfort to patients with reduced need for analgesia. A shorter weaning period from mechanical ventilation is among the benefits for patients with co-morbid states.

Aged↗

The effect of Nigella sativa oil against experimental allergic encephalomyelitis via nitric oxide and other oxidative stress parameters.

Reactive oxygen species (ROS) including nitric oxide (NO) are thought to be involved in inflammatory processes, exacerbating inflammation and tissue damage in multiple sclerosis (MS). The oil extracts of Nigella sativa (N. sativa) has been known as an antioxidant and antiinflammatory agent. The aim of the present study was to investigate the hypothesis that N. sativa components provide protection against oxidative stress induced by experimental autoimmune encephalomyelitis (EAE) in rats. For this purpose, EAE was induced in rats by using guinea pig myelin basic protein (MBP) in Freud's adjuvant with addition of heat-killed M. Tuberculosis H37Ra to test this hypothesis. In study groups, N. sativa was given by oral gavage to the rats. Treatment of the rats with N. sativa inhibited ROS production induced by EAE showing diminished levels of MDA of both brain and medulla spinalis tissues. Although there was a significant decrease in brain NO level, there was an increase in medulla spinalis NO level after EAE induction in rats. N. sativa regulated tissue NO levels in some extend when applied together with EAE. When N. sativa was given alone to the rats, no changes were shown in brain, medulla spinalis, and serum oxidant/antioxidant parameters. In conclusion, N sativa may protect brain and medulla spinalis tissues against oxidative stress induced by EAE. In addition, N. sativa display its antioxidant and regulatory effects via inflammatory cells rather than the host tissue (brain and medulla spinalis) for EAE in rats.

Animals↗

Vitamin E protects against acetone-induced oxidative stress in rat red blood cells.

Acetone may induce oxidative stress leading to disturbance of the biochemical and physiological functions of red blood cells (RBCs) thereby affecting membrane integrity. Vitamin E (vit E) is believed to function as an antioxidant in vivo protecting membranes from lipid peroxidation. The aim of the present study was the evaluation of possible protective effects of vit E treatment against acetone-induced oxidative stress in rat RBCs. Thirty healthy male Wistar albino rats, weighing 200-230 g and averaging 12 weeks old were randomly allotted into one of three experimental groups: Control (A), acetone-treated (B) and acetone + vit E-treated groups (C), each containing ten animals. Group A received only drinking water. Acetone, 5% (v/v), was given with drinking water to B and C groups. In addition, C group received vit E dose of 200 mg/kg/day i.m. The experiment continued for 10 days. At the end of the 10th day, the blood samples were obtained for biochemical and morphological investigation. Acetone treatment resulted in RBC membrane destruction and hemolysis, increased thiobarbituric acid reactive substance (TBARS) levels in plasma and RBC, and decreased RBC vit E levels. Vit E treatment decreased elevated TBARS levels in plasma and RBC and also increased reduced RBC vit E levels, and prevented RBC membrane destruction and hemolysis. In conclusion, vit E treatment appears to be beneficial in preventing acetone-induced oxidative RBC damage, and therefore, it can improve RBC rheology.

Acetone↗

Demographic analysis and outcome features in a transplant outpatient clinic.

AIM: This retrospective report analyzed the demographic features of kidney transplant outpatients grafted in Turkey and in different regions of the world. METHODS: The patients were divided into 4 groups: Every cohort was subgrouped as either receiving a cadaveric (CT) or a live donor transplant (LT) performed in our institute (ICT, n = 147, ILT, n = 304), other institutions in Turkey (TCT, n = 16, TLT, n = 86), or in a foreign country (FCT, n = 66, FLT, n = 154). RESULTS: Among the patients with functional grafts, FLT transplantations, of which the vast majority were paid transplantations, constituted the second largest group (n = 105) following ILT (n = 214). In the ILT group, 5- and 10-year graft survival rates were 76% and 50%, respectively, and patient survival rates were 88% and 78%, respectively. Considering the FLT group, 5- and 10-year graft survival figures were 70% and 42%, respectively, while patient survival rates in these periods were 81% and 69%, respectively. Patients with paid donor transplantations were characterized by a high risk of unconventional infectious complications in the early period, while midterm patient and graft survival was somewhat better than expected considering the high rate of complications in the early period. CONCLUSIONS: Paid organ transplantation should be discouraged. Organ donation should be stimulated by every means to avoid potentially fatal unconventional infections after transplantation from paid donors. If patients receive a paid transplant, however, they should be closely followed for these complications, since, if they survive the early period the midterm and long-term outcomes are quite reasonable.

Adult↗

Multiple metastatic malignant meningioma: a case report.

We report a case of a 27-year-old man who presented with a clinical history of swelling on the left side of his head. MRI scan showed a left frontal meningioma. The patient underwent a macroscopically complete resection. The histological diagnosis was malignant meningioma. Ten months after the initial diagnosis, multiple distant metastases were detected. Risk factors leading to metastasis in this case are discussed with a review of the literature.

Adult↗

[Gender and pain].

Epidemiological, psychophysical and prevalence studies reveal that women have greater and more variable pain than men. Gender differences in pain are brought by genetic, physiological, anatomical, neural, hormonal, lifestyle and cultural factors. While women are more vulnerable to pain than men, they have more ways to deal with it. The clinical applicability of findings from the studies on gender differences in pain may lead to improve not only diagnosis but also treatment with various drugs and techniques.

Female↗

IL-2 and IL-10 levels in induced sputum and serum samples of asthmatics.

BACKGROUND: There is consisting evidence that asthma is associated with airway inflammation. Originally IL-10 and IL-2 were described as lymphokines produced by T cells in mediating cellular infiltration into the airways and continue to be of interest in evaluating asthma pathogenesis. The aim of this study was to evaluate the serum and sputum levels of IL-2 and IL-10 in asthmatic subjects and healthy controls and to correlate disease activity and other clinical indices with concentrations of IL-2 and IL-10 in serum and sputum samples. METHODS: We evaluated cell profiles and IL-2 and IL-10 levels in induced sputum samples and in serum samples of 6 mild, 5 moderate, 7 severe asthmatic patients and 5 healthy controls by using ELISA. RESULTS: The mean IL-2 in sputum samples of asthmatics and controls were 35.3 +/- 13.2 pg/ml and 35.3 +/- 8.4 pg/ml, respectively. The mean IL-2 in serum samples of asthmatics and controls were 42.7 +/- 21.1 pg/ml and 30.3 +/- 2.4 pg/ml, respectively. Both levels did not result in any statistically significant difference between asthmatics and controls. There was no correlation between serum and sputum IL-2 levels, however sputum IL-2 levels correlated with percentage of sputum lymphocytes (p < 0.03, r = 0.51). The mean IL-10 levels in sputum samples of asthmatics and controls were 4.4 +/- 3.3 pg/ml and 3.9 +/- 5.9 pg/ml, respectively, the mean IL-10 level in serum of asthmatics and controls were 4.1 +/- 3.8 pg/ml and 2.3 +/- 2.5 pg/ml, respectively. We could not find statistically significant difference of serum or sputum IL-10 levels between asthmatics and controls. There was only correlation between serum and sputum IL-10 levels in asthmatics (p < 0.0008, r = 0.73). There was no difference between asthmatic subgroups regarding sputum and serum levels of IL-2 and IL-10. No correlation could be demonstrated between sputum or serum IL-2 and IL-10 levels and clinical severity. CONCLUSIONS: We have demonstrated the presence of detectable concentrations of the IL-2 and IL-10 in serums and induced sputum samples of asthmatics, however, they have no predictive value for asthma since their levels are not increased in asthmatic patients over controls. Moreover, IL-2 level positively correlated with lymphocyte percentage in induced sputum. The results suggest that measurement of IL-2 and IL-10 concentrations in serum and sputum will not be of diagnostic use in asthma and a reflection of the severity of asthmatic airway inflammation.

Adult↗

The outcome of pregnancy among patients receiving hemodialysis treatment.

Pregnancy among women receiving hemodialysis as a renal replacement therapy is rare and the chance of a successful delivery is relatively low. In this article, we present 3 cases of women conceiving either before or after the initiation of hemodialysis. The various risks of each pregnancy and the outcome are discussed as well as the latest management guidelines for pregnant dialysis patients.

Adult↗