Preparation of ABCBA-type block copolymers by use of macro-initiators containing peroxy and azo groups

Some new macroinitiators ( 5 ) containing azo and peroxy groups were synthesized by transformation of esters of poly(ethylene glycol) ( 1 ) (PEG) of different molecular weight with hydroxyl end groups and an azo group in the middle into the corresponding polymers with tert-butylperoxycarbonyl end groups by reaction with terephthaloyl chloride and subsequently with tert-butyl hydroporoxide. Decomposition in the presence of styrene at 60°C or with 3,6,9-triazaun-decane-1,11-diamine in presence of methyl methacrylate gave the corresponding ABA block copolymer 6 and the ABBA block copolymer 7 , respectively. Both block copolymers were used as polymeric initiators. The ABCBA block copolymer 8 was synthesized from 6 and methyl methacrylate or from 7 and styrene by thermally induced polymerization at 80°C. The resulting block copolymers were separated from the homopolymers by selective solvent extraction and characterized by spectroscopic and fractional precipitation methods.     

Biochemical profile of blood serum of siraz <Emphasis Type="Italic">Capoeta capoeta umbla</Emphasis>

Seasonal changes in blood plasma biochemistry of siraz Capoeta capoeta umbla were determined throughout 1 year. In the present study, while the highest values for glucose and globulin were found in winter, the values for increased activities of total protein, albumin, calcium, sodium levels, albumin/globulin ratio, lactate dehydrogenase, and alkaline phosphatase were determined in summer. We determined that blood biochemistry values of siraz, which were positively affected by water temperature and pH, except glucose and globulin. Glucose and globulin were negatively affected by water temperature and pH. Consequently, it was concluded that the seasons are key factors when blood parameters are used as biomarkers for environmental alterations. It is difficult to define the most important factors affecting seasonal changes of blood biochemistry in fish.     

Lumbar spinal stenosis in a young individual as a result of ligamantum flavum ossification: A case report

INTRODUCTIONSymtomatic lumbar ligamantum flavum calcification is quite rare in the young age group.PRESENTATION OF CASEThe authors report a case of young adult with diagnosis of lumbar spinal stenosis, presenting with leg pain and neurological deficits. Computerized tomography (CT) scan and magnetic resonance (MR) imaging studies revealed ossification of the ligamantum flavum as the causative factor of the disease and the patient recovered completely after the decompressive operation.DISCUSSIONIt is emphasized that attention should be given to this rare etiological factor of lumbar spinal stenosis.CONCLUSIONComplete relief can be achieved with early and adequate surgery.     

Spatial and temporal expression of vasodilator-stimulated phosphoprotein (VASP) in fetal and adult human cerebral cortex

Vasodilator-stimulated phosphoprotein (VASP) is a member of the Ena/VASP protein family and was for the first time identified in human platelets. VASP plays a role for cell adhesion and cell migration because of E/DFPPPPXD/E amino acid sequence in its structure which gives reaction with focal adhesion proteins. In this study we suggest that VASP expression may have important role for neural cell migration, differentiation, axonal growth and angiogenesis during prenatal cerebral cortical development. Our aim is to detect VASP expression by means of immunohistochemistry and Western blot analysis in developing human neocortex and adult brain cortex (n = 12 samples from first, second, and third trimesters and n = 3 adult normal cerebral cortex). Our results suggest that VASP showed different immunostaining patterns between cerebral cortical plates in prenatal and adult human brain samples. We observed that the expression patterns of the VASP protein are clearly identified in fibers, cytoplasm of neural cells and endothelial cells of vessels. We detected that VASP indicates progressive expression from the adult brain to second trimester neocortexes. Therefore, we suggest that VASP may play a crucial role in the regulation of human neonatal cerebral cortical development.     

CCM2 expression during prenatal development and adult human neocortex

Cerebral cavernous malformation (CCM) is one of the most common types of vascular malformations of the central nervous system, affecting nearly one in 200 people. CCM lesions are characterized by grossly dilated vascular channels lined by a single layer of endothelium. Genetic linkage analyses have mapped three CCM loci to CCM1, CCM2 and CCM3. All three causative genes have now been identified allowing new insights into CCM pathophysiology. We focused on the CCM2 protein that might take place in blood vessel formation; we report here the expression patterns of CCM2 in prenatal development and adult human neocortex by means of immunohistochemistry and Western blot analysis. CCM2 was obviously detected in vascular endothelium and neuroglial precursor cells during development and also observed in arterial endothelium, neurons, some of the glial cells in adult neocortex. The expression patterns suggest that it could be one of the arterial markers whether this is a cause or a consequence of an altered vascular identity. CCM2 might play a role during vasculogenesis and angiogenesis during human brain development. Furthermore, with this study, CCM2 have been described for the first time in developing human neocortex.     

Unveiling the optical parameters of vanadium dioxide in the phase transition region: a hybrid modeling approach

The phase change behavior of vanadium dioxide (VO₂) has been widely explored in a variety of optical and photonic applications. Commonly, its optical parameters have been studied in two extreme regimes: hot (metallic) and cold (insulating) states. However, in the transition temperatures, VO₂ acts like an inherent metamaterial with mixed metallic-insulating character. In this range, the portions of metallic and insulating inclusions are tuned by temperature, and therefore a gradual change of optical parameters can be achieved. In this paper, a universal hybrid modeling approach is developed to model VO₂ in the intermediate region. For this aim, the measured reflectivity data, is analyzed and matched through the transfer matrix method (TMM) simulations where an effective medium theory (EMT) is employed. Based on the findings of this approach, not only the relative portions of inclusions are tailored but also their grain shapes are significantly altered in the transition range. Finally, the modeling approach is testified by experimental findings through dynamic device applications operating at short and mid infrared wavelengths. In addition, the hysteretic behaviors on electrical, optical, and structural parameters of the VO₂ film along the heating and cooling cycles are demonstrated by the experiments and scrutinized by the simulations.

A universal hybrid modeling approach is developed to model VO₂ in transition, revealing dynamic behavior of metallic inclusions and grain shapes.     

Mechanical bowel obstruction due to colonic hemangioma: report of a case.

Colon hemangiomas are rare benign vascular lesions which are usually seen in teenagers. The frequent presentation is repetitive painless rectal bleeding. Colonic hemangiomas are occasionally found in the rectosigmoid area. A 62-year-old male patient was admitted to the hospital with the complaints of mechanical bowel obstruction. The radiological imaging techniques revealed a transverse colon tumor. Consequently, the patient was operated, and transverse colectomy and end-to-end anastomosis were performed. No postoperative complications occurred. The pathologic examination revealed cavernous hemangioma of the transverse colon. This report describes a very rare case of bowel obstruction due to colonic hemangioma.     

Idiopathic synchronous central giant cell granulomas involving both the maxilla and mandible: a case report

The central giant cell granuloma is a well-defined lesion of the jaws and reports of multiple lesions are very uncommon. The authors report the case of a patient with idiopathic synchronous multiple central giant cell granulomas involving both the maxilla and the mandible. Surgical curettage of the lesions was performed. At the end of the 24 months follow-up, no recurrence was detected.     

Recipient splenic artery utilization for arterial re-anastomosis in living donor liver transplantation: single-center experience

Thrombosis of recipient hepatic artery is a life threatening complication for liver transplantation. The etiology of hepatic arterial thrombosis is multi-factorial and can be caused by intimal dissection, poor surgical technique and coagulopathies. The patency of hepatic arterial flow is very important for both graft survival and patient survival. Intraoperative diagnosis of inadequate hepatic arterial flow found with Doppler ultrasonography is essential in order to achieve good results after liver transplantation. Urgent re-anastomosis is necessary when the arterial blood flow is insufficient. We performed 317 living donor liver transplantations from July 2004 to July 2011. We used recipient splenic artery for hepatic artery reconstruction in six patients. These six patients were included in this study. Using the recipient splenic artery is a simple, safe and practical alternative for hepatic artery re-anastomosis in living donor liver transplantations.