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    111In-pentetreotide scintigraphy in medulloblastoma
    (Taylor & Francis As, 2007) Yuksel, Mahmut; Lutterbey, Gotz; Biersack, Hans Juergen; Elke, Urs; Hasan, Carola; Gao, Zairong; Bode, Udo
    Medulloblastoma (MB) is a primitive neuroectodermal tumour constituting a grade IV brain malignancy. Early and correct detection of recurrence or metastasis is desirable for follow-up of patients in this entity. Frequent expression of somatostatin receptors by MB lesions facilitates functional tumour imaging by somatostatin receptor scintigraphy (SRS). To investigate the value of SRS in the follow-up of MB, the results of ten consecutive patients (seven children and three adults) undergoing additional imaging with In-111-pentetreotide were reviewed. Four, 24 and 48 h p.i. planar and whole body images as well as a SPECT study at 4 h p.i. were acquired after intravenous injection of 109 +/- 35 MBq In-111-pentetreotide (Octreoscan). SRS yielded 11 positive and ten negative imaging results, compared to 17 positive and four negative in magnetic resonance imaging (MRI). The lesion-by-lesion analysis with a total of 44 lesions revealed a sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 42%, 83%, 94%, 18% for SRS and 89.5%, 50%, 92%, 43% for MRI. Based on a per-patient analysis, considering the patient as to be either tumour-free or tumour-positive by one imaging modality, the following values for sensitivity, specificity, PPV and NPV were obtained: 61%, 100%, 100%, 30% for SRS and 94%, 67%, 94%, 67% for MRI. MRI remains the first step imaging technique in medulloblastoma patients before and after surgery and during the follow-up providing the highest sensitivity. However, to improve specificity and contribute to correct diagnosis in MB In-111-pentetreotide scintigraphy should be considered as a confirmatory second step imaging tool, especially in case of equivocal MRI results. Moreover, a positive SRS scan might serve as a reference before and after somatostatin receptor targeted radiotherapy.
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    Effects of carvedilol on plasma levels of pro-inflammatory cytokines - in patients with ischemic and nonischemic dilated cardiomyopathy
    (Texas Heart Inst, 2007) Kurum, Turhan; Tatli, Ersan; Yuksel, Mahmut
    We prospectively investigated the effects of adding carvedilol to the standard treatment of ischemic and nonischemic dilated cardiomyopathy (DCM), by measuring the plasma levels of pro-inflammatory cytokines. Sixty patients with DCM (35 ischemic and 25 nonischemic) were divided into 2 subgroups: patients on standard therapy alone (digoxin, angiotensin-converting enzyme inhibitors, and diuretics) and patients on standard therapy plus carvedilol. Study participants' serum levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2), and interleukin-6 (IL-6) were measured at the beginning and again at the end of the study. Left ventricular ejection fraction and left ventricular diastolic function were evaluated by means of radionuclide ventriculography In ischemic patients on carvedilol, levels of IL-6 and TNF-alpha dropped significantly (P= 0.028 and P=0.034, respectively). In ischemic patients on standard treatment plasma IL-2 levels were elevated after treatment (P=0.047). No significant differences occurred in IL-6 levels, while TNF-alpha levels were elevated (P=0.008). In nonischemic patients on carvedilol, IL-6 and TNF-alpha levels dropped significantly (P=0.018 and P=0.004, respectively). The left ventricular ejection fraction increased significantly (P=0.006). In nonischemic patients on standard treatment, no significant change occurred in any value. Carvedilol suppressed the plasma levels of TNF-alpha and IL-6 in both ischemic and nonischemic patients. The carvedilol effect was more pronounced in patients with nonischemic dilated cardiomyopathy than in those with ischemic disease.
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    Evaluation of pulmonary alveolo-capillary permeability in Type 2 diabetes mellitus using technetium 99mTc-DTPA aerosol scintigraphy and carbon monoxide diffusion capacity
    (Elsevier Science Inc, 2006) Ozsahin, Kemal; Tugrul, Armagan; Mert, Selva; Yuksel, Mahmut; Tugrul, Gozde
    The thickening of alveolar basement membrane is found in autopsies, along with microvascular pathologies, in Type I and 2 diabetes mellitus (DM). To detect the function and permeability of alveolar basement membrane, carbon monoxide diffusion capacity (DLCO) and technetium 99m-diethyltriaminepentaaceticacid (Tc-99m-DTPA) aerosol scintigraphy methods can be used. The aim of this study was to determine alveolar basement membrane damage using these two methods. Nineteen women and 6 men, nonsmoking, Type 2 DM cases, without any lung and/or heart disease and who had neither anemia nor obesity, made up the patient group. They were compared with six female and nine male healthy cases who had the same characteristics with the diabetes cases. All of the cases DLCO were measured by single-breath method and 99mTc-DTPA aerosol scintigraphy was performed. DLCO showed no difference between the two groups. Aerosol scintigraphy was significantly decreased in the diabetic group (P=.01). In cases with > 5 years of diabetic duration (P <.01), in cases with glycolized hemoglobin (HbA(1c)) <= 8% (P <.05) and > 8% (P <.05), and in microangiopathic cases (P <.01), alveolo-capillary permeability was significantly decreased than in the control group. Among the same groups, no significant difference could be detected for DLCO. The permeability of alveolar basement membrane can reduce in respect to diabetes duration and poor metabolic control. According to our investigation, Tc-99m-DTPA aerosol scintigraphy method is more sensitive than DLCO method for determining these pathologies. (c) 2006 Elsevier Inc. All rights reserved.
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    Incidence of anti-heparin/platelet factor 4 antibodies and heparin-induced thrombocytopenia in medical patients
    (Galenos Yayincilik, 2009) Demir, Muzaffer; Tekgunduz, Emre; Edis, Mustafa; Duran, Enver; Kurum, Turan; Yigitbasi, Omer; Yuksel, Mahmut
    Objective: Heparin-induced thrombocytopenia (HIT) is a life threatening complication of heparin therapy, causing thrombosis. The aim of our study was to find out the frequencies of HIT antibody seroconversion and clinical HIT in Turkish medical patients on different forms of heparins. Materials and Methods: Our study included 61 patients who were an unfractionated heparin (UFH) (n: 37) and low molecular weight heparin (LMWH) (n: 24) therapies. The frequency of HIT antibody formation was determined by means of antigenic (ELISA), and functional assays (serotonin release assay-SRA). Results: The seroconversion rates in UFH and LMWH groups were found to be 18.9% and 4.1% (ELISA), and 8.1% and 4.1% (SRA), respectively. One patient (2.1%) on UFH therapy developed deep vein thrombosis. No thromboembolic event was observed in patients taking LMWH. Conclusion: Seroconversion rates by means of antigenic and functional assays and clinical HIT were more common in patients on UFH than patients on LMWH therapy. (Turk J Hematol 2009; 26: 171-5)
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    Incidence of antiheparin-platelet factor 4 antibodies and heparin-induced thrombocytopenia in Turkish patients undergoing cardiac surgery
    (Sage Publications Inc, 2007) Demir, Muzaffer; Duran, Enver; Yigitbasi, Omer; Vural, Ozden; Kurum, Turhan; Yuksel, Mahmut; Turgut, Burhan
    The frequency of antiheparin-platelet factor 4 antibodies by means of antigenic and functional assays (C-14-serotonin release assay and citrated plasma platelet aggregation) was determined in 115 Turkish patients undergoing cardiac surgery. Blood samples were taken immediately before surgery and on days 5 and 10 +/- 2. Platelet counts were recorded and thrombotic events were determined by clinical methods. Antibody generation measured by enzyme-linked immunosorbent assay before surgery (n = 44) and on days 5 (n = 44) and 10 (n = 115) was 15.9%, 34.1%, and 65.2%, respectively. Positive samples from functional assays were 4.4% on day 0 and 7.0% on day 10. All positive samples had been negative on day 0. A high frequency of antiheparin-platelet factor 4 antibody generation and a low frequency of clinical heparin-induced thrombocytopenia were determined in these patients. These results obtained for Turkish patients are similar to those of other studies of heparin-induced thrombocytopenia.
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    Results of a pilot study on the effects of propofol and dexmedetomidine on inflammatory responses and intraabdominal pressure in severe sepsis
    (Elsevier Science Inc, 2009) Tasdogan, Muhittin; Memis, Dilek; Sut, Necdet; Yuksel, Mahmut
    Study Objective: To compare the effects of an intravenous infusion of propofol and the alpha-2 adrenoceptor, dexmedetomidine, on inflammatory responses and intraabdominal pressure (LAP) in severe sepsis after abdominal surgery, specifically, serum cytokine levels (interleukin [IL]-1, IL-6, and tumor necrosis factor [TNF]-alpha) and IAP. Design: Prospective, single-center study. Setting: University hospital. Patients: 40 adult ICU patients who had undergone ileus surgery and who were expected to require postoperative sedation and ventilation. Interventions: Patients received either a loading dose infusion of propofol (Group P; n = 20) one mg/kg over 15 minutes followed by a maintenance dose of one to three mg/kg/hr (n = 20, Group P) or a loading dose of dexmedetomidine of one mu g/kg over 10 minutes followed by a maintenance dose of 0.2-2.5 mu g/kg/h (n = 20, Group D) at the 24th hour. Measurements: Biochemical and hemodynamic parameters, cytokine levels, and IAP were recorded before the start of the study and at the 24th and 48th hours. Main Results: TNF-alpha levels were significantly lower at the 24th hour (14.66 +/- 4.40 pg/mL vs. 21.21 +/- 11.37 pg/mL, respectively) and at the 48th hour (21.25 +/- 15.85 pg/mL vs. 46.55 +/- 35.99 pg/mL, respectively) in Group D. IL-1 levels were significantly lower at the 24th hour (5.03 +/- 0.15 pg/mL vs. 6.23 +/- 2.09 pg/mL, respectively) and the 48th hour (5.01 +/- 0.37 pg/mL vs. 6.42 +/- 2.76 pg/mL, respectively) in Group D. IL-6 levels were significantly lower at the 24th hour (253.1 +/- 303.6 pg/mL and 511.3 +/- 374.8 pg/mL, respectively) and at the 48th hour (343.5 +/- 393.4 pg/rnL and 503.7 +/- 306.4 pg/mL, respectively) in Group D. Intraabdominal pressure also was significantly lower at the 24th hour (12.35 +/- 5.84 mmHg vs, 18.1 +/- 2.84 mmHg, respectively) and the 48th hour (13.9 +/- 6.15 mmHg vs. 18.7 +/- 3.46 mmHg, respectively) in Group D. Conclusion: Dexmedetomidine infusion decreases TNF-a, IL-1, and IL-6 levels and IAP more than a propofol infusion. (C) 2009 Elsevier Inc. All rights reserved.