Zonguldak Karaelmas University

About: Zonguldak Karaelmas University is a based out in . It is known for research contribution in the topics: Population & Copolymer. The organization has 1939 authors who have published 4296 publications receiving 62466 citations.

Fulminant hepatic failure associated with propylthiouracil: A case report with treatment emphasis on the use of plasmapheresis

Abstract: Propylthiouracil is a commonly used medication for hyperthyroidism. Though propylthiouracil-induced hepatotoxicity is a rarely encountered problem, death due to fulminant hepatic failure may occur. In the English literature, only 34 cases have been described with severe hepatotoxicity secondary to this drug. Here we report a case of fulminant hepatic failure due to propylthiouracil and review the issues of treatment and management with special emphasis on the use of plasmapheresis in such situations.

Obstructive sleep apnea syndrome and erectile dysfunction: does long term continuous positive airway pressure therapy improve erections?

Abstract: Objectives : The aim of this age-matched, controlled, prospective clinical study was to investigate frequency and degree of erectile dysfunction (ED) in patients with obstructive sleep apnea syndrome (OSAS) and to evaluate the results of only continuous positive airway pressure (CPAP) therapy on ED in patients with OSAS. Materials and Methods: A total of 90 patients were evaluated for potential OSAS. They were given an International Index of Erectile Function questionnaire (IIEF) and Beck Depression Inventory. Sixty-two patients with the diagnosis of OSAS were regarded as study group. Twenty-eight patients in whom the OSAS was excluded, were regarded as the control group. Biochemical and hormonal laboratory evaluation were performed. Then all patients underwent a full-night in laboratory polysomnography examination. The degree of OSAS were evaluated by an expert from chest diseases department. Results : When compared to the control group, a decrease in IIEF-5 scores was found in patients with OSAS. However, this decrease was not statistically significant. After 3 months of CPAP usage in patients with mild to moderate and severe degree OSAS, improvement in IIEF-5 scores was statistically significant. Mean value of IIEF-5 score was 16.63±5.91 before CPAP and were improved up to 20.92±6.79 (P=0.001). Conclusion : It is not certainly possible to say that OSAS is clearly associated with ED. However, after 3 months of regular CPAP usage, ED complaints in patients with OSAS might improve positively. Trials with larger series may give more conclusive data. Key Words: Sleep disorder, erectile dysfunction, obstructive sleep apnea syndrome, CPAP

Determination of the 30-year creep trend on the Ismetpaşa segment of the North Anatolian Fault using an old geodetic network

Abstract: The Ismetpasa segment of the North Anatolian Fault was ruptured during both the 1944 (M w = 7.2) Gerede and 1951 (M w = 6.9) Kursunlu earthquakes. The field studies carried out in the aftermath of these two major earthquakes showed that the Ismetpasa segment had experienced a creep movement. To monitor the surface creep, a geodetic network with six control points was established on the segment. This network was observed three times—in 1972, 1982 and 1992. Based on our evaluations of those observations, the creep on the segment was geodetically determined to be 1.02 cm/year (1972–1982) and 0.93 cm/year (1982–1992) respectively. In 1999, the North Anatolian Fault experienced two major shocks—the M w = 7.4 Golcuk and M w = 7.2 Duzce earthquakes—both on the western part of the Ismetpasa fault. Using the global positioning system, our surveying team observed the network one more time in 2002 to assess whether these earthquakes affected the creep of the Ismetpasa segment, or not. The evaluation of the observations revealed a creep of 0.78 cm/year for the period 1992–2002. This result reveals that the creep of the segment has decreased in a linear fashion between 1972 and 2002 and that it had not been triggered by the Golcuk and Duzce earthquakes.

Synthesis and characterization of diblock, triblock, and multiblock copolymers containing poly(3‐hydroxy butyrate) units

Abstract: A poly[(R,S)-3-hydroxybutyrate] macroinitiator (PHB-MI) was obtained through the condensation reaction of poly[(R,S)-3-hydroxybutyrate] (PHB) oligomers containing dihydroxyl end functionalities with 4,4′-azobis(4-cyanopentanoyl chloride). The PHB-MI obtained in this way had hydroxyl groups at two end of the polymer chain and an internal azo group. The synthesis of ABA-type PHB-b-PMMA block copolymers [where A is poly(methyl methacrylate) (PMMA) and B is PHB] via PHB-MI was accomplished in two steps. First, multiblock active copolymers with azo groups (PMMA-PHB-MI) were prepared through the redox free-radical polymerization of methyl methacrylate (MMA) with a PHB-MI/Ce(IV) redox system in aqueous nitric acid at 40°C. Second, PMMA-PHB-MI was used in the thermal polymerization of MMA at 60°C to obtain PHB-b-PMMA. When styrene (S) was used instead of MMA in the second step, ABCBA-type PMMA-b-PHB-b-PS multiblock copolymers [where C is polystyrene (PS)] were obtained. In addition, the direct thermal polymerization of the monomers (MMA or S) via PHB-MI provided AB-type diblocks copolymers with MMA and BCB-type triblock copolymers with S. The macroinitiators and block copolymers were characterized with ultraviolet–visible spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography, cryoscopic measurements, and thermogravimetric analysis. The increases in the intrinsic viscosity and fractional precipitation confirmed that a block copolymer had been obtained. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1789–1796, 2004