Search PubMed⌕ Search

Biomedical subjects

M Sahin

Publications and source records attributed to M Sahin.

At least 37 records · Page 2Linked to original sources

Immunoglobulin deficiency in kidney allograft recipients: comparative effects of mycophenolate mofetil and azathioprine.

Mycophenolate mofetil (MMF) has commonly been substituted for azathioprine (AZA) in kidney transplantation and has been shown to have a greater effect on T cell function and also B cell function than AZA. Although immunoglobulin deficiency has been investigated in patients treated with protocols that include AZA, it has not extensively been studied in MMF-based immunosuppressive protocols. To evaluate this effect, we conducted a prospective study and recruited 49 patients. The patients received either AZA- (group 1) or MMF- (group 2) based therapy. A total of 17 patients in group 1 and 24 patients in group 2 completed the study. Immunoglobulin levels were evaluated before and in every month after transplantation for a 6-month period. Total infectious episodes were recorded and evaluated after 6 months in both groups. While no significant differences have been found in group 1, there were significant decreases in IgG, M, and A levels in group 2 after 6 months (IgG: 11.6+/-1.5-6.8+/-2.0 g/L, P<0.0001; IgM: 2.20+/-1.40-1.40+/-1.16 g/L, P=0.02; IgA: 1.40+/-0.70-1.07+/-0.86 g/L P=0.03). Two patients (11.7%) in group 1 and 11 patients in group 2 (45.8%) were found to have at least one low level of immunoglobulin (P=0.03). When the infectious complications were evaluated, the mean number of infection episodes in each patient was 1.3+/-1.6 and 0.5+/-0.7 for the MMF and AZA groups, respectively (P=0.06). Recurrent urinary tract infection developed in eight patients and seven of those were in group 2. In group 2, 7 of 11 patients with low immunoglobulin levels had recurrent urinary tract infection (63%), while no patient who had normal immunoglobulin levels developed any recurrent urinary tract infections (P<0.001). After 6 months, MMF was changed to AZA in these seven patients, who had both recurrent urinary tract infections and low immunoglobulin levels. All but one patient was found to have normal immunoglobulin levels after 3 months of conversion and only two episodes of infection were recorded during this period. We suggest that serum immunoglobulin levels can be monitored in patients taking MMF, and conversion from MMF to AZA may be an alternative for patients with low immunoglobulin levels and recurrent urinary tract infections.

Adult↗

The value of the TIMI frame count method in the diagnosis of coronary no-reflow: a comparison with myocardial perfusion SPECT in patients with acute myocardial infarction.

The state of no-reflow (i.e. inadequate myocardial tissue perfusion despite normal arterial flow proven in angiography after pharmacological or mechanical interventions) is considered to be a marker of a poor prognosis. Although the Thrombolysis in Myocardial Infarction (TIMI) flow grade is a valuable and widely used qualitative measure in angiography trials, it is limited by its subjective and categorical nature. Recently, the TIMI frame count method (TFC) was proposed for detecting no-reflow. In our study we aimed to compare TFC values with myocardial perfusion single photon emission computed tomography (SPECT) findings to investigate the additional role of the former method in the evaluation of no-reflow. Twenty patients (16 men and four women; mean age 58+/-9 years) with first acute myocardial infarction were included in the study after thrombolytic therapy. Coronary angiography (CAG) was performed 5-7 days later. The TIMI flow grade and TFC values were determined in angiography examinations. A TIMI flow of less than grade 3 and a TFC value >27 were considered to be pathologically decreased for coronary artery blood flow. Tc tetrofosmin myocardial rest SPECT was carried out 24 h after coronary angiography. SPECT images were scored on a four-point scale in 20 myocardial segments and the total defect score was calculated from the sum of defect scores in 20 segments. Wall motion was assessed using the wall motion score index in echocardiography (ECWSI). The occurrence rates of angiographic no-reflow, pathological TFC and perfusion defects in SPECT were calculated as 40% (8/20), 47% (8/17; non-measurable in three patients with TIMI grade 0), and 55% (11/20), respectively. Perfusion defects were present and the TIMI frame count value was increased in all patients with angiographic no-reflow (TIMI grade <3). The occurrence rate of perfusion defects and increased TFC was equal (42%) in all 12 patients having TIMI grade 3 flow. Increased TFC was demonstrated in four of five patients having perfusion defects and TIMI grade 3 flow (80% compatibility with SPECT). TIMI frame count and ECWSI values were significantly higher in patients having perfusion defects than in patients with normal perfusion ( <0.05). It is concluded that the TIMI frame count is a valuable method in the detection of patients with TIMI grade 3 flow, with no-reflow, and increases the specificity of coronary angiography in the evaluation of the response to thrombolytic therapy. A pathologically increased TFC value with TIMI grade 3 flow during CAG seems to be a good indication for the use of myocardial perfusion SPECT in the definitive diagnosis and/or follow-up of such patients.

Acute Disease↗

Occurrence of anthrax in Kars district, Turkey.

The aims of the study were to determine the prevalence of anthrax by bacteriologic methods in cattle and sheep between January 2000 and September 2001 and to determine the distribution of this zoonotic disease in humans in Kars district, Turkey. Bacillus anthracis was isolated and identified in 34 out of 38 (91%) cattle and 11 out of 17 (64%) sheep samples obtained from organs suspected of anthrax. The records of the Governmental Health Branch showed that 89 cases of cutaneous anthrax were diagnosed in humans during the study periods in the same district.

Animals↗

EphA receptors regulate growth cone dynamics through the novel guanine nucleotide exchange factor ephexin.

Eph receptors transduce short-range repulsive signals for axon guidance by modulating actin dynamics within growth cones. We report the cloning and characterization of ephexin, a novel Eph receptor-interacting protein that is a member of the Dbl family of guanine nucleotide exchange factors (GEFs) for Rho GTPases. Ephrin-A stimulation of EphA receptors modulates the activity of ephexin leading to RhoA activation, Cdc42 and Rac1 inhibition, and cell morphology changes. In addition, expression of a mutant form of ephexin in primary neurons interferes with ephrin-A-induced growth cone collapse. The association of ephexin with Eph receptors constitutes a molecular link between Eph receptors and the actin cytoskeleton and provides a novel mechanism for achieving highly localized regulation of growth cone motility.

Actins↗

Effects of diphenhydramine HCl and methylprednisolone in the prevention of abdominal adhesions.

OBJECTIVE: The purpose of this study was to determine the effects of diphenhydramine hydrochloride and methylprednisolone in peritoneal adhesions. MATERIALS AND METHODS: Forty-eight male rats were used in the study. The rats were anesthetized by 5 mg/kg ketamine hydrochloride. After opening the abdomen, 10 longitudinal incisions of 2 to 3 cm in length were made on the right parietal peritoneum, and a 2 cm(2) peritoneal layer was excised from the left abdominal wall. The abdomen was closed with 3/0 silk suture. Group I was the control group, group II was given 10 mg/kg diphenhydramine intravenously, group III was given 20 mg/kg methylprednisolone intravenously, and group IV was administered both of the drugs in the above doses. A blood sample of 2 mL was taken from the rats on the 14th day after the operation. The animals were then sacrificed. The abdomen was opened and abdominal adhesions were examined. A tissue sample of 1 g was taken from the abdominal incision line. Albumin, zinc, and hemoglobin levels and leucocyte counts in the blood were determined as well as hydroxyproline levels in the tissue. RESULTS: Numbers of adhesions were as follows: 9 in group I, 3 in group II, and 2 in group III. No adhesion was observed in group IV. Albumin, zinc, and hemoglobin levels and leucocyte counts were found to be similar in all groups. Hydroxyproline levels in the tissue were significantly lower in groups III and IV than in groups I and II (P <0.05). CONCLUSIONS: Diphenhydramine and methylprednisolone reduced postoperative adhesions significantly in rats. Further investigations are needed in order to use these drugs as antiadhesive agents in humans.

Abdomen↗

Short-term histopathologic effects of different intracavernosal agents on corpus cavernosum and antifibrotic activity of intracavernosal verapamil: an experimental study.

OBJECTIVES: To evaluate the short-term effects of different intracavernosal agents and to investigate the antifibrotic effect of verapamil combined with these intracavernosal agents. METHODS: Forty-five Sprague-Dawley rats weighing 400 to 500 g each (mean weight 435.27 +/- 13.65 g) were equally divided into nine groups (n = 5). Papaverine (group 1), alprostadil (group 2), sodium nitroprusside (group 3), and verapamil (group 4) were injected alone intracavernously in 0.2-mL doses. Verapamil combined with papaverine, alprostadil, and sodium nitroprusside in 0.2-mL doses (0.1 mL verapamil and 0.1 mL vasoactive agent) were injected in groups 5 through 7. Group 8 was kept as a control group without injection, and isotonic saline alone was injected in group 9 during the same period. The intracavernous injection was done twice weekly with a 4-day interval. At the end of the study, total penectomy and multiple liver biopsies were performed to evaluate the histopathologic effects of the vasoactive agents and to test the liver function. RESULTS: In all groups, the structure of the corpora cavernosa was well preserved generally and appeared similar to the control tissue. However, localized edema, fibrosis, macrophage infiltration, and polymorphonuclear leukocytes were found only at the injection site. Although these findings were not different from the findings in the saline and alprostadil groups, they were slightly more extensive in the papaverine and sodium nitroprusside alone groups and also in the vasoactive agent plus verapamil groups. Although mononuclear lymphocyte infiltration was found in the portal areas, advancing into the liver parenchyma, the liver function tests were within normal limits. CONCLUSIONS: We observed that intracavernous injection, except with nitroprusside, caused focal intracavernosal fibrosis and edema. We believe these effects might not be caused by just the drug, but also by needle trauma, since general fibrosis was not observed in the short term. However, nitroprusside has a severe fibrotic effect on cavernosal tissue in the short term. Moreover, intracavernous verapamil injection could not prevent the fibrosis in the short term.

Alprostadil↗

Investigation of the vertebrobasilar arterial system in vertigo by vestibulocochlear test, SPECT and angiography.

OBJECTIVE: Perfusion of the areas of cochleovestibular structures was investigated using Tc-99m HMPAO single photon emission computerized tomography (SPECT) in the young patients with vertigo presumed to have peripheral vestibular abnormalities and compared the results with cochleovestibular test results, and vertebrobasilar angiography findings. METHODS AND PATIENTS: The study was performed on 20 patients with vertigo and 17 control subjects who had performed vertebral arteriography due to another disease. The patients with vertigo presumed to be on peripheral vestibular disorder were included in the study. Systemic and otorhinolaryngological examination were carried out. Audiovestibular function was evaluated in all patients and control subjects. Brain SPECT was performed with a one-head rotating gamma camera system from 64 projections into a 64x64 matrix, using low energy and high-resolution fan beam collimators with a sampling time of 30 s. The images taken from cerebellum, temporal, parietal and occipital lobes which are supplied by a vertebrobasilar system were compared visually with the other side and asymmetry in the perfusion was searched. After cochleovestibular tests and laboratory had been completed, vertebral arteriography was performed bilaterally in all patients. Results of digital subtraction angiography (DSA) and the vestibulocochlear test were compared with images of SPECT. Data analysis was done with Yates Chi(2) and percentages of sensitivity and specificity were calculated. RESULTS: There was vestibular test and cochlear test abnormalities in eight and ten of the patients with vertigo, respectively. SPECT imaging showed hypoperfusion and decreased regional blood flow in 12 of the patients. There was statistically significant differences between the study and control groups in SPECT (P<0.05). Five patients showed abnormal findings in DSA examinations. CONCLUSION: It is believed that SPECT may be helpful in the detection of vascular pathology in the patients with vertigo.

Adult↗

Oral melanin pigmentation related to smoking in a Turkish population.

OBJECTIVE: Besides genetic factors, tobacco smoking has been found to be the major cause of oral melanin pigmentation. The purpose of the present study was to evaluate the frequency of oral melanin pigmentation in a Turkish population and to present its correlation with clinical parameters relevant to periodontal status in current smokers, non-smokers, former smokers. METHOD: A sample of 496 patients was randomly selected. The subjects were interviewed regarding their smoking habits. They were clinically examined by a single examiner for the presence of oral melanin pigmentation in different oral mucosal regions. The same examiner recorded the clinical parameters including GI (gingival index), PI (plaque index), BOP (bleeding on probing), PD (probing depth) and GR (gingival recession). Examiner 2 completed a questionnaire concerning skin color and smoking habits. RESULTS: In the study group, 41% were current smokers, 46% nonsmokers and 13% former smokers. The frequencies of pigmented areas were significantly higher in current smokers than in those without any smoking habits. The clinical parameters revealed similar findings for all groups. Low GI and BOP values were observed for current smokers when compared with non-smokers and former smokers, respectively. GI values were significantly associated with the pigmentations in gingiva. CONCLUSIONS: The results of our study show that smokers in a Turkish population had significantly more pigmented oral surfaces than nonsmokers.

Adult↗

Outcome of severe refractory status epilepticus in children.

PURPOSE: Refractory status epilepticus (RSE) is the persistence of seizure activity despite appropriate therapy; it is treated with high-dose suppressive anesthetic agents. We report here the outcome of RSE in a large series of children. METHODS: We retrospectively reviewed cases of RSE treated at Children's Hospital, Boston, between 1992 and 2000. Factors evaluated included age, history of seizures or neurologic impairment, etiology, outcome, including mortality or return to baseline, and initial EEG findings. RESULTS: Twenty-two patients ages 4.5 months to 18 years were admitted to the intensive care unit for RSE. All were treated with high-dose suppressive therapy consisting of pentobarbital, midazolam, propofol infusion, or high-dose phenobarbital, either alone, or in combination, for < or =146 days. The overall mortality was seven of 22. Mortality was related to etiology, age, and EEG findings. No death occurred in the remote symptomatic group, and three of four younger than 3 years died, whereas only four of 18 older than 3 years died. The mortality rate among patients with focal abnormalities on the EEG was lower than that among those with multifocal or generalized abnormalities. None of the children with normal premorbid neurologic status returned to baseline. CONCLUSIONS: Our data demonstrate a high mortality and morbidity for childhood RSE. Mortality is related to etiology and is higher in younger children and with multifocal or generalized abnormalities on the initial EEG.

Adolescent↗

Analysis of atmospheric conditions during air pollution episodes in Ankara, Turkey.

This paper presents a detailed analysis of the meteorological conditions that are associated with strong air pollution episodes in Ankara, Turkey. Based on climatological and air quality data [SO2 and TSP (total suspended particulates)] obtained for the winter months during 1989-1994, the analysis showed that the presence of weak atmospheric pressure gradients and warm air advection were the most important factors leading to high SO2 and TSP concentrations. In addition, the onset of the high air pollution episodes was generally associated with a trend toward negative vorticity at the 850-hPa level.

Air Movements↗

Pentavalent technetium-99m DMSA uptake in pseudofractures of osteomalacia.

Tc-99m MDP and Tc-99m (V) DMSA images are described from a 49-year-old woman with chronic renal insufficiency complicated by osteomalacia. Clinical, biochemical, and radiologic bone profiles were compatible with osteomalacia. Osteomalacia is a condition associated with disorders in which mineralization of the organic matrix is defective. All bone lesions visualized with Tc-99m MDP also showed increased uptake of Tc-99m (V) DMSA. Tc-99m (V) DMSA accumulation has been reported in many malignant and some benign conditions. Pseudofractures in osteomalacia could be included in the spectrum of benign lesions that accumulate Tc-99m (V) DMSA.

Bone and Bones↗

Evaluation of lymphatic drainage of cold thyroid nodules with intratumoral injection of Tc-99m nanocolloid.

PURPOSE: The lymphatic system may show variations throughout the entire body. Knowledge of the variations and aberrant lymph drainage are important when planning surgical treatment and radiotherapy. The aim of this study was to evaluate the intratumoral injection technique in the detection of lymphatic drainage of proved or possibly malignant cold thyroid nodules. MATERIALS AND METHODS: The study group consisted of 13 patients with palpable solitary cold thyroid nodules. None of the patients had cystic nodules on ultrasound examination. After fine-needle aspiration biopsy (at least 3 days later), 15 MBq (0.4 mCi) Tc-99m nanocolloid particles in a small volume (0.2 ml) were injected into the nodule. Dynamic images (60 frame x 1 minute) were acquired during the first hour, followed by static anterior and lateral images at 90 and 120 minutes. RESULTS: Radiopharmaceutical was present in the systemic circulation in two patients, possibly as a result of paratumoral injection. Eleven patients had intratumoral accumulation in early frames. Lymph nodes draining the thyroid nodule were visualized in 10 of 11 patients. In the dynamic acquisition period of 7 of 10 patients, the first draining lymph node could also be identified. Only 5 of 13 patients had malignant nodules. Lymphatic metastases were detected in one patient's specimens. CONCLUSIONS: Preoperative visualization of lymphatic pathways may be used when planning for thyroid cancer surgery. Sentinel node detection could yield valuable additional information in these patients.

Adult↗

Prolonged treatment of refractory status epilepticus in a child.

Barbiturate anesthesia, which is commonly used for refractory status epilepticus, is an effective treatment, but with many significant complications. The relationship between the duration of this extreme therapy and the ultimate outcome of refractory status epilepticus has not been well studied. We report a 7-year-old girl who presented with refractory status epilepticus secondary to presumed encephalitis with a focal lesion on cranial magnetic resonance imaging. She was treated for 70 days with high-dose antiepileptic drugs and recovered with a residual seizure disorder. This case suggests that, if the status epilepticus is due to a reversible cause such as encephalitis, neurologic recovery may occur despite this very prolonged course of extreme therapy.

Anticonvulsants↗

The management of liver hydatid cysts by percutaneous drainage.

OBJECTIVE: To investigate the effect of percutaneous drainage on liver hydatid cysts. DESIGN: A retrospective case study. SETTING: Department of Surgery, Selçuk University, Konya, Turkey. PATIENTS: Forty-five patients with 83 liver hydatid cysts (types I and II according to the classification of Gharbi and colleagues) followed up for a mean of 30 months (range from 14 to 36 months). INTERVENTION: The cysts were drained percutaneously with ultrasonographic guidance and then irrigated with 0.05% silver nitrate solution through a fine needle. Albendazole was administered 48 hours before percutaneous drainage and for 2 months after the procedure to prevent the implantation of spilled scolices. MAIN OUTCOME MEASURES: Complications of the procedure, decrease in size of the cyst cavity, recurrence and dissemination of the cysts. RESULTS: All the cysts were treated successfully by percutaneous drainage. Anaphylactic shock developed in 1 (2.2 %) patient, and mild allergic reactions were observed in 2 (4.4 %) patients during the interventional procedure. Follow-up ultrasonography and CT demonstrated a statistically significant (p < 0.01) decrease in the mean cyst size. Recurrence and dissemination were not observed during the follow-up period. CONCLUSION: Percutaneous fine-needle aspiration and drainage is effective for managing cystic liver hydatid disease in selected cases.

Adult↗

[The value of C-reactive protein and leucocyte count in preventing negative appendectomies].

This study was designed to determine the values of C-Reactive Protein measurements (an acute phase reactant, CRP) and leucocyte counts in prevention of negative appendectomies. Despite improvements in diagnostic methods, negative appendectomy rates still remain between 10-30% in acute appendicitis. Cost-effective and easily applicable diagnostic methods with prompt results are required to reduce negative appendectomy rates. In this prospective study, one hundred twenty-six patients were operated on for initial diagnosis of acute appendicitis between July 1999 and July 2000. CRP and leucocyte count were measured in all cases. The data of the outcomes of clinic and pathological findings were analyzed statistically. Among the 126 study patients, 71 (56.3%) were male and 55 (43.7%) were female. 79 (62.6%) cases had noncomplicated appendicitis, 27 (21.4%) cases had complicated appendicitis and 20 (15.8%) cases had negative appendectomy. The mean CRP level was significantly higher (p < 0.001) in patients with complicated acute appendicitis than in those with noncomplicated acute appendicitis and in those with negative appendectomy. The mean leucocyte count was significantly lower (p < 0.001) in patient with negative appendectomy than in those with noncomplicated appendicitis and in those with complicated appendicitis. Although CRP increases with inflammation, it increases markedly after the occurrence of complication. The increase in leucocyte count is early sign of appendix inflammation. CRP measurements or leucocyte counts are not effective alone to prevent negative appendectomies.

Adult↗

Effect of pedunculated seromuscular flap on bursting strength of intestinal anastomosis after corticosteroid treatment.

PURPOSE: This study was designed to investigate the protective effect of a pedunculated seromuscular flap on intestinal anastomosis after corticosteroid treatment. METHODS: Forty male Sprague-Dawley rats were divided into four groups, and all animals underwent intestinal anastomosis. Two groups, with or without seromuscular flap wrapping, received 5 mg cortisone acetate, and two groups received placebo (saline) preoperatively for 16 days. Anastomotic strength was defined as bursting pressure (in millimeters of mercury). The pedunculated seromuscular flap was prepared from a segment of intestine next to the anastomosis. Intestinal bursting strength at the anastomotic site was measured at Postoperative Day 8. RESULTS: The anastomotic bursting strength was significantly lower in the steroid groups at Postoperative Day 8 (P < 0.01). The pedunculated seromuscular flap increased the strength of the anastomosis both in the steroid and control groups (P < 0.05). CONCLUSION: The adverse effect of corticosteroids on intestinal anastomoses may be prevented by a pedunculated seromuscular flap.

Anastomosis, Surgical↗

Effect of laparoscopic cholecystectomy on platelet aggregation.

The purpose of this study was to investigate the effect of laparoscopic cholecystectomy on platelet function. We operated on 40 women with symptomatic gallbladder stone, 20 of whom (study group) underwent laparoscopic cholecystectomy and 20 of whom (control group) open cholecystectomy. Patients with a history of bleeding, abnormal platelet count, or systemic disorders and those who were on salicylates, heparin, or oral anticoagulants were excluded. Blood parameters were checked at the beginning and the end of the operation, including platelet aggregation using adenosine 5'-diphosphate (ADP), collagen, and ristocetin in a whole-blood aggregometer. Platelet aggregation was evaluated by percent aggregation. Platelet aggregation due to collagen and ristocetin increased significantly at the end of the operation in the study group (p < 0.001). Aggregation due to ADP did not differ significantly from the start to the end of the operation. Control group results did not show any differences. Although the clinical findings of aggregated platelet are not frequently observed in practice, we suggest that laparoscopy increases platelet aggregation.

Abdomen↗

Antiepileptic drug-induced visual hallucinations in a child.

The neurologic signs and symptoms of carbamazepine and phenytoin toxicity, such as ataxia, dysarthria, and nystagmus, are well known. The psychiatric manifestations of toxicity, such as psychosis and hallucinations, however, are less widely recognized. This study reports the case of a 9-year-old male with seizures who developed intermittent complex visual hallucinations after therapy with antiepileptic drugs was begun. This study considered seizures, migraine, underlying psychiatric diathesis, and drug toxicity as possible etiologies but after extensive investigation concluded that his symptoms were most likely a drug side effect.

Anticonvulsants↗