Showing papers by "Istanbul University published in 1998"

Thalidomide in the Treatment of the Mucocutaneous Lesions of the Behcet Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial

Abstract: Background: Recurrent oral and genital ulcers are the most frequent problem in the management of the Behcet syndrome. Uncontrolled experience suggests that thalidomide may help prevent recurrences of these ulcers. Objective: To determine the efficacy of two thalidomide dosages in the treatment of mucocutaneous lesions of the Behcet syndrome. Design: Randomized, double-blind, placebo-controlled trial. Setting: Specialist outpatient clinic for the Behcet syndrome in Turkey. Patients: 96 male patients with the Behcet syndrome who primarily had mucocutaneous lesions without major organ involvement. Intervention: Thalidomide, 100 mg/d or 300 mg/d, or placebo for 24 weeks. Measurements: Sustained absence of any oral and genital ulceration during treatment (complete response) and changes in the number of mucocutaneous lesions. An additional evaluation was done 4 weeks after treatment ended. Results: A complete response occurred in 2 of the 32 patients (6% [95% CI, 0.8% to 20.8%]) receiving thalidomide, 100 mg/d; in 5 of the 31 patients (16% [Cl, 5.5% to 33.7%]) receiving thalidomide, 300 mg/d; and in none of the 32 patients (0% [Cl, 0% to 10.9%]) receiving placebo (P = 0.031). The suppressive effect of thalidomide with either dosage was evident at 4 weeks for oral ulcers (P < 0.001) and at 8 weeks for genital ulcers (P < 0.001) and follicular lesions (P = 0.008). This effect persisted during treatment but diminished rapidly after treatment was discontinued. Both thalidomide dosages led to significant increases in the number of erythema nodosum lesions during the first 8 weeks of treatment (P = 0.03). Polyneuropathy developed in 4 patients (1 in the 100-mg/d group and 3 in the 300-mg/d group); in 3 of these patients, the condition was diagnosed after the trial had ended. Conclusions: Thalidomide is effective for treating the oral and genital ulcers and follicular lesions of the Behcet syndrome. A dosage of 100 mg/d is as effective as a dosage of 300 mg/day.

Behçet's disease and the nervous system.

Abstract: Behcet's disease is a multisystem inflammatory disorder with unknown aetiology. It is a disease of young adults with a more severe course in males subjects. Its prevalence is high in the Mediterranean basin and Japan and has been linked with human leucocyte antigen B5 (HLA-B5) in those countries. According to the diagnostic criteria formed by the International Study Group, recurrent oral ulceration is a prerequisite, with two more typical symptoms or signs. Neurological involvement is one of the most devastating manifestations of Behcet's disease. The involvement is either caused by primary neural parenchymal lesions (neuro-Behcet) or secondary to major vascular involvement (vasculo Behcet). The course is relapsing-remitting, secondary progressive or primary progressive. The most commonly involved area is the brain stem, with additional symptoms or signs, hemispherical involvement with mental changes being the most common. Intracranial hypertension, usually owing to dural sinus thrombosis, has a special place in Behcet's disease. The most common clinical findings are pyramidal signs. Sensory symptoms or signs are much less frequent, and hemianopia and higher cortical function disturbances as well as pure cerebellar syndrome are rare features. Cerebrospinal fluid usually has a high protein content and/or pleocytosis. Notably, in the acute period most patients have lesions shown by magnetic resonance imaging (MRI) extending from the brain-stem to diencephalic structures. Differential diagnosis from multiple sclerosis can be difficult in patients with hemispheric white matter MRI hyperintensities. Immunosuppressives are used in treatment.

Characterization of the cloned human intermediate-conductance Ca2+-activated K+ channel

Abstract: The human intermediate-conductance, Ca2+-activated K+ channel (hIK) was identified by searching the expressed sequence tag database. hIK was found to be identical to two recently cloned K+ channels...

Prostitution in Five Countries: Violence and Post-Traumatic Stress Disorder

Abstract: We initiated this research in order to address some of the issues that have arisen in discussions about the nature of prostitution In particular: is prostitution just a job or is it a violation of human rights? From the authors' perspective, prostitution is an act of violence against women; it is an act which is intrinsically traumatizing to the person being prostituted We interviewed 475 people (including women, men and the transgendered) currently and recently prostituted in five countries (South Africa, Thailand, Turkey, USA, Zambia) In response to questionnaires which inquired about current and lifetime history of physical and sexual violence, what was needed in order to leave prostitution and current symptoms of post-traumatic stress disorder (PTSD) we found that violence marked the lives of these prostituted people Across countries, 73 percent reported physical assault in prostitution, 62 percent reported having been raped since entering prostitution, 67 percent met criteria for a diagnosis of PTSD On average, 92 percent stated that they wanted to leave prostitution We investigated effects of race, and whether the person was prostituted on the street or in a brothel Despite limitations of sample selection, these findings suggest that the harm of prostitution is not culture-bound Prostitution is discussed as violence and human rights violation

Does television viewership play a role in the perception of quality of life

Abstract: The authors hypothesized that television viewership influences materialism and dissatisfaction with standard of living, which in turn contributes to feelings of dissatisfaction with life. They collected data from five countries to examine the issue in a variety of cultural and media environments. The countries and types of samples were: United States (consumer panel and college students), Canada (urban households), Australia (urban households), Turkey (urban households), and China (urban households). The results were generally consistent with the hypotheses. However, most of the support came from the U.S. samples. Two possible explanations may account for the findings. One is that the effect of television viewership on life satisfaction is a unique phenomenon that is applicable only to the United States. Given the disparity of viewership levels between the U.S. and other countries, that explanation has some face validity. The other is that the effects were less evident in non-U.S. samples because...

Survival and predictors of disability in Turkish MS patients

Abstract: Objective: To examine the natural history, survival, and prognostic factors in a sample of Turkish MS patients. Method: This multicenter study included 1,259 definite MS patients diagnosed according to the criteria of Poser et al. Actuarial analysis of selected disability levels of 3, 6, 8, and 10 achieved with the Expanded Disability Status Scale (EDSS); a multivariate Cox regression analysis for prognostic factors related to time to reach EDSS ≥ 6; and Pearson9s correlation coefficient for individual factors were performed. Results: The survival (±SE) at 15 years from onset was 94.6 ± 2.9%, and at 25 years was 89.0 ± 5.8%. The disability reached by 15 years was EDSS ≥ 3 in 66.4%, EDSS ≥ 6 in 41.2%, EDSS ≥ 8 in 10.5%, and EDSS = 10 in 5.4%. The most significant unfavorable prognostic factors were progressive course (relative risk [RR], 3.73; CI, 2.71 to 5.13) and sphincter symptoms at onset (RR, 1.86; CI, 1.23 to 2.82), followed by male sex, motor symptoms at onset, and a high attack frequency within the first 5 years. Primary progressive disease was correlated positively with male sex ( r = 0.0895, p = 0.001), older age ( r = 0.1807, p = 0.000), and motor ( r = 0.1433, p = 0.000) or sphincter symptoms ( r = 0.1001, p = 0.000) at onset, unlike relapsing-remitting and secondary progressive disease. Conclusions: Although a slightly better prognosis is observed in the Turkish MS population, early prognostic factors are similar to most of the previous Western series. Primary progressive disease, mostly seen in older men with motor and sphincter involvement at onset, has a worse prognosis and may represent a distinct behavioral variant of MS.

Modeling of Copper(II), Cadmium(II), and Lead(II) Adsorption on Red Mud

Abstract: The adsorption of toxic heavy metal cations, i.e., Cu(II), Cd(II), and Pb(II), on red muds has been modeled with the aid of a modified Langmuir approach assuming single-site adsorption and of a double-site binding model incorporating the effect of pH. For equilibrium concentrations of metal solutions between 0.03 and 5.8 mmol.dm −3 and equilibrium pH between 4.4 and 5.6, adsorption equilibrium constants corresponding to single- and double-site binding were found by linear and nonlinear least-squares approximation, respectively, and the double-site model was shown to conform better to experimental data. The contributions of the monomeric and dimeric hydroxo-complexes of Cu(II) to total copper adsorption at a fixed pH were also investigated. The Langmuir parameters of adsorption were found with the aid of the linearized Langmuir isotherm. This work aims to clarify heavy metal adsorption behavior on composite sorbents consisting of hydrated oxides.

Frequency of Dissociative Disorders Among Psychiatric Inpatients in a Turkish University Clinic

Abstract: OBJECTIVE: The aim of this study was to determine the rate of dissociative disorders among psychiatric inpatients in a university clinic in Turkey. METHOD: The Dissociative Experiences Scale was used to screen 166 consecutive inpatients admitted to the psychiatry clinic of a university hospital. The patients who had scores higher than 30 were matched for age and gender with 19 of the patients who scored below 10 on the scale. The patients in both groups were then interviewed with the Dissociative Disorders Interview Schedule by interviewers who were blind to their diagnoses and scores on the Dissociative Experiences Scale. Patients who were diagnosed as having a dissociative disorder according to the Dissociative Disorders Interview Schedule were then interviewed by a clinician. RESULTS: Twenty-four (14.5%) of the 166 patients had a score higher than 30 on the Dissociative Experiences Scale; 17 patients (10.2%) were diagnosed as having a dissociative disorder according to the Dissociative Disorders Interv...

Diagnosis and treatment of common bile duct stones (CBDS) Results of a consensus development conference

Abstract: Background: Common bile duct stones (CBDS) are a frequent problem (10–15%) in patients with symptomatic cholecystolithiasis. Over the last decade, new diagnostic and surgical techniques have expanded the options for their management. This report of the Consensus Development Conference is intended to summarize the current state of the art, including principal guidelines and an extensive review of the literature. Methods: An international panel of 12 experts met under the auspices of the European Association of Endoscopic Surgery (EAES) to investigate the diagnostic and therapeutic alternatives for gallstone disease. Prior to the conference, all the experts were asked to submit their arguments in the form of published results. All papers received were weighted according to their scientific quality and relevance. The preconsensus document compiled out of this correspondence was altered following a discussion of the external evidence made available by the panel members and presented at the public conference session. The personal experiences of the participants and other aspects of individualized therapy were also considered. Results: Our panel of experts agreed that the presence of common bile duct stones should be investigated in all patients with symptomatic cholecystolithiasis. Based on preoperative noninvasive diagnostics, either endoscopic retrograde cholangiopancreaticography (ERCP) or intraoperative cholangiography should be employed for detecting CBDS. Eight of the 12 panelists recommended treating any diagnosed CBDS. For patients with no other extenuating circumstances, several treatment options exist. Stones can be extracted during ERCP, or either before or (in exceptional cases) after laparoscopic or open surgery. Bile duct clearance should always be combined with cholecystectomy. Evidence for further special aspects of CBDS treatment is equivocal and drawn from nonrandomized trials only. Conclusions: The management of common bile duct stones is currently undergoing some major changes. Many diagnostic and therapeutic strategies need further study.

High Level of Unequal Meiotic Crossovers at the Origin of the 22q11.2 and 7q11.23 Deletions

Abstract: Interstitial chromosomal deletions at 22q11.2 and 7q11.23 are detected in the vast majority of patients affected by CATCH 22 syndromes and the Williams‐Beuren syndrome, respectively. In a group of 15 Williams‐Beuren patients, we have shown previously that a large number of 7q11.23 deletions occur in association with an interchromosomal rearrangement, indicative of an unequal crossing-over event between the two homologous chromosomes 7. In this study, we show that a similar mechanism also underlies the formation of the 22q11.2 deletions associated with CATCH 22. In eight out of 10 families with a proband affected by CATCH 22, we were able to show that a meiotic recombination had occurred at the critical deleted region based on segregation analysis of grandparental haplotypes. The incidences of crossovers observed between the closest informative markers, proximal and distal to the deletion, were compared with the expected recombination frequencies between the markers. A significant number of recombination events occur at the breakpoint of deletions in CATCH 22 patients (P = 2.99·10 ‐7 ). The segregation analysis of haplotypes in three-generation families was also performed on an extended number of Williams‐Beuren cases (22 cases in all). The statistically significant occurrence of meiotic crossovers (P = 4.45·10 ‐9 ) further supports the previous findings. Thus, unequal meiotic crossover events appear to play a relevant role in the formation of the two interstitial deletions. The recurrence risk for healthy parents in cases where such meiotic recombinations can be demonstrated is probably negligible. Such a finding is in agreement with the predominantly sporadic occurrence of the 22q11.2 and 7q11.23 deletions. No parent-of-origin bias was observed in the two groups of patients with regard to the origin of the deletion and to the occurrence of inter- versus intrachromosomal rearrangements.

Glycolysis of poly(ethylene terephthalate) wastes in xylene

Abstract: To reclaim the monomers or prepare intermediates suitable for other polymers zinc acetate catalayzed glycolysis of waste poly(ethylene terephthalate) (PET) was carried out with ethylene or propylene glycol, with PET/glycol molar ratios of1 : 0.5–1 : 3, in xylene at 170–245°C. During the multiphase reaction, depolymerization products transferred to the xylene medium from the dispersed PET/glycol droplets, shifting the equilibrium to glycolysis. Best results were obtained from the ethylene glycol (EG) reaction at 220°C, which yielded 80 mol % bis-2-hydroxyethyl terephthalate monomer and 20 mol % dimer fractions in quite pure crystalline form. Other advantages of employment of xylene in glycolysis of PET were improvement of mixing at high PET/EG ratios and recycling possibility of excess glycol, which separates from the xylene phase at low temperatures. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 2311–2319, 1998

Imbalance between Lipid Peroxidation and Antioxidant Status in Preeclampsia

Abstract: Lipid peroxidation and the antioxidant system were investigated in the plasma and placenta of normal and preeclamptic pregnant women. A significant increase in thiobarbituric acid reactive substance (TBARS), significant decreases in total thiol (t-SH) content and superoxide dismutase (SOD) activity, and unchanged vitamin C levels and glutathione peroxidase (GPx) activity were observed in the plasma of preeclamptic women compared to women with normal pregnancies. In placentas from preeclamptic women TBARS levels were significantly elevated, while glutathione and vitamin C levels and GPx, glutathione S-transferase and SOD activities were decreased. After delivery, the elevated TBARS values decreased significantly and the reduced SOD activity and t-SH contents increased significantly. We concluded that preeclampsia is associated with an imbalance between lipid peroxides and the antioxidant system.

Androgens and fetal growth.

Abstract: Boys are heavier than girls at term birth. Children with a 46,XY karyotype and androgen insensitivity syndrome (clinically complete form and/or proven mutations in the androgen receptor gene) were found to have a birth weight comparable to that of girls. These findings support the hypothesis that the difference in birth weight between boys and girls is generated by androgen action.

Traumatic intracranial carotid tree aneurysms.

Abstract: Objective This study was designed to elucidate the requirements for angiographic evaluation in blunt head injuries, the timing of angiography, and the selection of appropriate therapeutic approaches Methods Twelve cases of traumatic aneurysms (TAs) in the intracranial carotid tree were analyzed in this study Neurological examination results, computed tomographic scans, pre- and postembolization cerebral angiograms, and follow-up data were included Results In 11 of 12 cases, TAs were of cranial base origin; in 1 case, the aneurysm was located in the distal anterior cerebral artery In seven of the cases with cranial base lesions, aneurysms were located in the intracavernous segment of the internal carotid artery; all of the computed tomographic scans for these cases demonstrated sphenoid sinus wall fractures and hematoma in the sphenoid sinus In two cases, although the initial angiograms revealed no lesions, a second study performed 2 weeks later demonstrated the presence of aneurysms Nine of the aneurysms were treated with endovascular techniques, two were managed conservatively, and the remaining one patient died with massive epistaxis while awaiting surgical treatment No morbidity or additional permanent neurological deficits occurred in the endovascularly treated patient group Conclusion Patients with head trauma who present with sphenoid sinus fractures and massive epistaxis should be evaluated for the development of TAs as soon as possible If the patients exhibit fractures without epistaxis, angiography should be deferred for 2 to 3 weeks; if the first angiographic evaluation reveals normal findings, repeated epistaxis should prompt a second angiographic evaluation Current treatment of TAs involves occlusion of the main artery through the use of endovascular techniques Cases involving internal carotid artery TAs of cranial base origin and patients who do not tolerate test occlusion require extracranial-to-intracranial bypass surgery

Sensory processing in the pallium of a mormyrid fish

Abstract: To investigate the functional organization of higher brain levels in fish we test the hypothesis that the dorsal gray mantle of the telencephalon of a mormyrid fish has discrete receptive areas for several sensory modalities. Multiunit and compound field potentials evoked by auditory, visual, electrosensory, and water displacement stimuli in this weakly electric fish are recorded with multiple semimicroelectrodes placed in many tracks and depths in or near telencephalic area dorsalis pars medialis (Dm). Most responsive loci are unimodal; some respond to two or more modalities. Each modality dominates a circumscribed area, chiefly separate. Auditory and electrical responses cluster in the dorsal 500 micrometer of rostral and caudolateral Dm, respectively. Two auditory subdivisions underline specialization of this sense. Mechanoreception occupies a caudal area overlapping electroreception but centered 500 micrometer deeper. Visual responses scatter widely through ventral areas. Auditory, electrosensory, and mechanosensory responses are dominated by a negative wave within the first 50 msec, followed by 15-55 Hz oscillations and a slow positive wave with multiunit spikes lasting from 200 to 500 msec. Stimuli can induce shifts in coherence of certain frequency bands between neighboring loci. Every electric organ discharge command is followed within 3 msec by a large, mainly negative but generally biphasic, widespread corollary discharge. At certain loci large, slow ("deltaF") waves usually precede transient shifts in electric organ discharge rate. Sensory-evoked potentials in this fish pallium may be more segregated than in elasmobranchs and anurans and have some surprising similarities to those in mammals.

Synthesis, structure elucidation and antimicrobial activity of some 3-hydroxy-2-naphthoic acid hydrazide derivatives

Abstract: In this study, some 1,4-disubstituted thiosemicarbazide,1,2,4-triazole and 1,3,4-thiadiazole type novel compounds derived from 3-hydroxy-2-naphthoic acid hydrazide were synthesized to screen for their antimicrobial activity. The structures of these substances were elucidated using elemental analysis and UV, 1H NMR, and mass spectral methods. All of these compounds were tested in vitro for their antibacterial and antifungal activity.

Stochastic maximum likelihood methods for semi-blind channel estimation

Abstract: A blind stochastic maximum likelihood (ML) channel estimation algorithm is adapted to incorporate a known training sequence as part of the transmitted frame. A hidden Markov model (HMM) formulation of the problem is introduced, and the Baum-Welch (1970) algorithm is modified to provide a computationally efficient solution to the resulting optimization problem. The proposed method provides a unified framework for semi-blind channel estimation, which exploits information from both the training and the blind part of the received data record. The performance of the ML estimator is studied, based on the evaluation of Cramer-Rao bounds (CRBs). Finally, some preliminary simulation results are presented.