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    Can exposure to manganese and extremely low freIuency magnetic fields affect some important elements in the rat teeth?
    (2012) Ince B.; Akdag Z.; Bahsi E.; Erdogan S.; Celik S.; Akkus Z.; Dalli M.
    Background: Length and level of exposure to electromagnetic fields (EMFs) is increasing in association with the widespread use of electrical and electronic devices and technological progress. The undesirable effects of extremely low freIuency magnetic fields (ELF-MFs) on health have attracted considerable interest. Materials and Methods: Sixty-four fourmonth- old male Wistar rats divided into eight groups of eight rats each were used. Seven groups were exposed to varying dosages of manganese (Mn) and a 50 Hz magnetic field (MF) of approximately 1 mT, while the last group was set aside as the cage control group and not subjected to any procedure. This study was intended to investigate the interactions between the application of MF and Mn and the elements Ca, Zn, Mg, and P thought to be involved in caries, in rat teeth. Results: Levels of Ca, Mg, Zn, and P in the experimental group rats were different to those in the control group. Conclusions: The results demonstrate that ELFMF and Mn can have significant effects on levels of elements in rat teeth. Further experimental and epidemiological studies of ELF-MF and Mn are needed in order to evaluate their dental effects.
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    Effect of homogeneous alkaline catalyst type on biodiesel production from soybean
    (National Institute of Science Communication and Information Resources (NISCAIR), 2016) Saydut A.; Kafadar A.B.; Aydin F.; Erdogan S.; Kaya C.; Hamamci C.
    Transesterification or alcoholysis is the most commonly applied method for biodiesel production. A catalyst is needed to improve the transesterification reaction and yield. The present study used soybean oil as the raw oil to mix with methanol and four strong alkali catalysts (NaOH, KOH, CH3ONa & CH3OK) to undergo a transesterification reaction. Transesterification was carried out using 100% excess alcohol, i.e., molar ratio of alcohol to soybean oil was 6:1, and catalyst concentration of 1% at 60°C. Alkali metal alkoxides were found to be more effective transesterification catalysts compared to hydroxides. Sodium methoxide was the most efficient catalyst, although KOH and NaOH could also be used because they are cheaper and are used widely in large scale processing.
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    A new preconcentration method for the determination of pb and ni in real samples by using amberlite xad-16 functionalized with 1,6-bis(2-carboxy aldehyde phenoxy)butane
    (Atomic Spectroscopy Press Limited, 2019) Oral E.V.; Erdogan S.; Temel H.; Ziyadanogullari B.; Ziyadanogullari R.
    In this study, a steady chelating resin matrix was formed by tying 1,6-bis(2-carboxy aldehyde phenoxy) butane to Amberlite XAD-16 resin by a-C=N-group. This synthesized adsorbent was placed into a minicolumn to separate and preconcentrate the lead and nickel ions before their determination by flame atomic absorption spectrometry (FAAS). The effects of many parameters on the preconcentration method were examined. The optimal pH value for the quantitative absorption of lead and nickel was pH 5.0. The percentage of recovery for lead and nickel was 99 ± 1.15% and 100 ± 2.70%, respectively. The detection limits of lead and nickel utilizing FAAS (3s, N= 20) were 1.47 and 1.16 µg/L, respectively. The effects of some matrix components on the recovery were analyzed. The suggested method was utilizied to determine lead and nickel in real water samples obtained from the River Tigris in Turkey, as well as in automobile exhaust particles, Romaine lettuce, and parsley. The accuracy of the proposed method was verified by using the standard addition method and the standard reference material NCS-DC 73350 Poplar Leaves. © Atomic Spectroscopy Press Limited. All rights reserved.
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    Regional cerebral blood flow and cytokines in young females with fibromyalgia
    (2002) Gur A.; Karakoc M.; Erdogan S.; Nas K.; Cevik R.; Sarac A.J.
    Objective. To determine whether there is any difference in regional cerebral blood flow (rCBF) and serum cytokine levels and association between clinical parameters and rCBF and serum cytokine levels in young females with flbromyalgia (FM). The other aim was to search whether the depression state has any effect on these two parameters. Methods. Nineteen women with FM and 20 healthy women had 99mTc-HMPAO brain single-photon-emission computed tomography (SPECT) to evaluate rCBF. Serum interleukin (IL) levels (IL I?, IL 2r, IL 6 and IL 8) were measured. Clinical and psychological evaluation was also carried out in FM patients and healthy controls. Results. The patients with FM had significantly higher radioactivity uptake ratio in right and left caudate nucleus (p = 0.009, p = 0.001, respectively) than healthy controls. There was statistically significant decrease in the 99mTc-HMPAO uptake in the right superior parietal (p = 0.041), gyrus rectalis (p 0.036) and pons (p = 0.023). FM patients had significantly higher serum IL 2r and IL 8 levels (p = 0.023, p = 0.011, respectively) than controls. Additionally, FM patients had significantly higher Fibromyalgia Impact Questionnaire (FIQ), Health Assessment Questionnaire (HAQ), and Hamilton Depression Rate scale (HDRS) scores (p = 0.000) than controls. Interestingly, the patients with mild depressive symptoms or without (i.e.HDRS-score ? 16) had significantly higher serum IL 8 levels (p = 0.027) and increased radioactivity uptake ratio in the pons (P = 0.036) than the patients with more severe depressive symptoms (i.e. HDRS-score > 16). With regard to regional cerebral blood flow, significant correlations were detected between RSP and morning stiffness (r = 0.70, p < 0.01) and sleep disturbance (r = -0.53, p < 0.05), and between gyrus rectalis and FIQ score. There were significant correlations between LCN and IL-2 (P = 0.025), between RSP and morning stiffness (P = 0.006), sleep disturbance (P = 0.021) according to multiple regression analysis test. Conclusion. This study shows a significant increase in rCBF of caudate nuclei, a reduction in the pons, some cortical regions activity and a increase in IL 8, IL2r levels of young female patients with FM. These findings are more prominent in patients with low HDRS scores.