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Öğe Assessment of alterations in regional cerebral blood flow in patients with hypothyroidism due to Hashimoto's thyroiditis(Springer, 2007) Kaya, M.; Cermik, T. F.; Bedel, D.; Kutucu, Y.; Tuglu, C.; Yigitbasi, Oe. N.Aim: The aim of this study was to assess regional cerebral blood flow (rCBF) using detailed semiquantative analysis of Tecnethium-99m hexamethylpropyleneamine (HMPAO) brain single-photon emission computered tomography (SPECT) in patients with hypothyroidism due to autoimmune thyroiditis. Patients, material and methods: Twenty patients (mean age: 42 +/- 9 yr) and 12 control subjects (mean age: 35.4 +/- 8.5 yr) were included in this study. The corticocerebellar rCBF ratios were obtained from 52 cerebral areas on 6 transaxial slices. By using control group rCBF ratios, lower reference values (RLV) (average ratio -2 SD) were calculated and the regions below RLV having an rCBF ratio were considered as abnormal decrease (hypoperfused) areas. Results: Significant reduced rCBF rates were measured for 15 (29%) cortical regions for the patient group. The areas in which significant reduced rCBF were demonstrated in the patient group were as follows: a) in the right hemisphere: superior frontal (slice 1 and 2), inferior frontal (slice 1), anterior temporal (slice 1 and 2), precentral gyrus (slice 1 and 2), postcentral gyrus (slice 1 and 2), and parietal cortex; b) in the left hemisphere: superior frontal (slice 1 and 2), inferior frontal (slice 1), caudate nucleus, and parietal cortex. The hypoperfusion was calculated in 154 (14%, 94 right and 60 left) cortical regions out of 1040 regions in the patient group. Conclusion: These findings indicate that the alteration of rCBF in patients with hypothyroidism due to Hashimoto's thyroiditis before T-4 therapy can be demonstrated with brain SPECT. Additionally, the degree of rCBF abnormalities could be determined with brain SPECT in patients with hypothyroidism due to Hashimoto's thyroiditis with or without neurologic or psychiatric symptoms.Öğe The assessment of the changes of regional cerebral blood flow using Tc-99m HMPAO SPET in patients with hyperparathyroidism(Springer, 2005) Cermik, T. F.; Kaya, M.; Ugur-Altun, H. B.; Bedel, D.; Berkarda, S.[Abstract Not Available]Öğe Chitin Extraction and Chitosan Production from Cell Wall of Two Mushroom Species (Lactarius Vellereus and Phyllophora Ribis)(Amer Inst Physics, 2017) Erdogan, S.; Kaya, M.; Akata, I.Chitin is an important polysaccharide found as supporting material in the cell wall of mushrooms. In this study, chitin and chitosan were obtained from the cell wall of two different mushroom species using chemical method and physicochemically characterized. The dry weight chitin contents of the mushroom species were determined as 11.4% for Lactarius vellereus and 7.9% for Phyllophora ribis. Chitosan yields of the chitins isolated from L. vellereus and P. ribis were 73.1% and 75.3%, respectively. While, the maximum degradation temperatures of vellereus and P. ribis chitins were found to be 354 degrees C and 275 degrees C by thermogravimetric analysis (TGA), the maximum degadation temperature of the chitosans obtained from these chitins were recorded as 262 degrees C and 229 degrees C, respectively. The crystalline index values of L. vellereus and P. ribis chitins were calculated as 64% and 49%, respectively according to the X-ray diffraction analysis (XRD) results. The scanning electron microscopy (SEM) indicated that there were no nanofiber or nanopores on the surface of the chitins and chitosans obtained from these two mushroom species. The results of this study revealed that L. vellereus and P. ribis had higher chitin contents than some other insects and mushroom species recorded in the literature and these species may be used as a potential chitin sources.Öğe Chitin extraction and chitosan production from Chilopoda (Scolopendra cingulata) with identification of physicochemical properties(Maik Nauka/Interperiodica/Springer, 2015) Zelencova, L.; Erdogan, S.; Baran, T.; Kaya, M.The Chilopoda is found in a broad array of terrestrial habitats from tropical rain forests to deserts and there are more than 8000 species worldwide. Chitin and chitosan were obtained from Scolopendra cingulata for the first time in this study and physico-chemically characterized. The dry weight chitin content of S. cingulata was found to be 8% of body weight, and it produced chitosan yields of 66%. Analyses results revealed that Chilopoda chitin was in the alpha-form. The chitosan derived from Chilopoda chitin has a low molecular weight (2.278 kDa). The surface morphology of chitin from S. cingulata consists of dispersed nanopores and nanofibres.Öğe The relation between the interpedicular distance and the maximum pedicular screw length in lumbar one vertebra(Edizioni Minerva Medica, 2011) Copuroglu, C.; Ciftdemir, M.; Yilmaz, A.; Ozcan, M.; Kaya, M.; Yalniz, E.Aim. The aim of this paper was to demonstrate the relation between the distance of the midline of the corpus and the screw entry point on the pedicle and the maximum screw length that can be applied in the pediculocorporeal screw trajectory. Methods. The distance between two pedicular screw entry points and the distance between screw entry point and the anterior cortex of the vertebra corpus in the midline, on computed tomography (CT) sections and the same distances on cadaveric bony L1 specimens, were measured. Interpedicular distance was divided into two and the distance between the midline and the screw entry point was found. These measurements were compared and a constant ratio was observed. The pedicular screw entry point was accepted as the point just lateral to the inferior articular process at the mid level of the transverse process. Results. When these measurements were compared, a constant ratio was observed. The ratio between the distance of the midline of the vertebra and the screw entry point and the distance between the screw entry point and the midline anterior cortex of the vertebral body, was 2.5 cm. When the distance between the midline of the vertebra and the screw entry point during the operation or by measuring half of the interpedicular distance on plane roentgenograms, is measured, the maximum length of the pedicular screw can be estimated. Conclusion. In this study, we described an easy method of determining the maximum pedicular screw length by measuring the distance between the midline level of the vertebra corpus (spinous process level) and pedicle screw entry point on coronal section.Öğe When the sourcil width is larger than the femoral neck, it can be a predictor for an upcoming hip fracture(Edizioni Minerva Medica, 2011) Copuroglu, C.; Yilmaz, A.; Ozcan, M.; Ciftdemir, M.; Unver, K. V.; Kaya, M.; Copuroglu, E.Aim. Response of the bone to pressure depends on the strength of the pressure applied. If the load, transferred from the sourcil to the femoral head, is heavy and if the femoral neck is large, development of load carrying structures will be greater. We aimed to evaluate the relationship between the width of the sourcil and the width of the femoral neck and their relation with the fracture type of the hip in correlation with the neck-shaft angle. Methods. This is a retrospective case series study (N.=320) including the instutional data between January 2007 through April 2010. The medial and lateral side of the sourcil was pointed on the AP X-ray, and the distance between these two points was measured. On the same AP X-rays, the radius at the thinnest width of the femoral neck was measured in millimetres. The width of the sourcil and the width of the femoral neck in normal hips were compared with the measurements of the fractured hips. Neck-shaft angles of all the hips were also measured. Results. The width of the sourcil is mostly equal to the width of the femoral neck in normal hips. The width of the sourcil was greater than the width of the femoral neck in hip-fractured patients. This shows that, if the sourcil is bigger than the femoral neck, the femoral neck cannot carry as much load as the sourcil and fractures may happen. If the neck-shaft angle is smaller than normal hips, we observed that collum femoris is broken and if the neck-shaft angle is bigger than normal hips, then intertrochanteric femur fracture occurs. Conclusion. When the sourcil width is larger than the femoral neck width, it can be a predictor for an upcoming hip fracture. Varus in the neck-shaft angle is a predictor for femoral neck fracture and valgus is a predictor for intertrochanteric fracture.
