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31.
S. Sezin Palabiyik Pinar Erkekoglu N. Dilara Zeybek Murat Kizilgun Dilek Ertoy Baydar Gonul Sahin Belma Kocer Giray 《Experimental and toxicologic pathology》2013,65(6):853-861
This study was designed to investigate the possible protective effect of lycopene against the renal toxic effects of OTA. Male Sprague-Dawley rats (<200 g, n = 6) were treated with OTA (0.5 mg/kg/day) and/or lycopene (5 mg/kg/day) by gavage for 14 days. Histopathological examinations were performed and apoptotic cell death in both cortex and medulla was evaluated by TUNEL assay. Besides, biochemical parameters and activities of renal antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), thioredoxin reductase (TrxR)], catalase (CAT), superoxide dismutase (SOD); concentrations of total glutathione (GSH), and malondialdehyde (MDA) levels were measured. OTA treatment was found to induce oxidative stress in rat kidney, as evidenced by marked decreases in CAT (35%) activity and GSH levels (44%) as well as increase in SOD activity (22%) vs control group. Furthermore, TUNEL analysis revealed a significant increase in the number of TUNEL-positive cells in cortex (49%) and medulla (75%) in OTA administrated group compared to control (p < 0.05). Lycopene supplementation with OTA increased GPx1 activity and GSH levels, and decreased apoptotic cell death in both cortex and medulla vs. control. The results of this study showed that at least one of the mechanisms underlying the renal toxicity of OTA is oxidative stress and apoptosis is the major form of cell death caused by OTA. Besides, our data indicate that the natural antioxidant lycopene might be partially protective against OTA-induced nephrotoxicity and oxidative stress in rat. 相似文献
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Pinar Altinci Murat Mutluay Leo Tjderhane Arzu Tezvergil‐Mutluay 《European journal of oral sciences》2019,127(1):1-9
Matrix metalloproteinases (MMPs) and cysteine cathepsins (CCs) can break down unprotected type I collagen fibrils in dentin matrix. This study investigated the use of potassium fluoride (KF) as a potential inhibitor of MMPs and CCs in dentin. Demineralized dentin beams were divided into groups (n = 10 in each group) and incubated in artificial saliva (AS, control), either alone or with one of seven concentrations of KF (6–238 mM fluoride) for 1, 7, and 21 d. After 21 d, all groups were further aged in AS for 6 months. Total MMP activity was screened using the colorimetric MMP assay. The activities of MMP‐2 and MMP‐9 were investigated using gelatin zymography. At the end of each incubation, changes in loss of dry mass and CC‐mediated or total dissolution of collagen peptides were measured via precision weighing, C‐terminal crosslinked telopeptide of type I collagen (CTX), and hydroxyproline (HYP) assays. The beams were examined using scanning electron microscopy. After 21 d, total MMP activities, dry mass loss, and CTX release for the groups exposed to 179 and 238 mM fluoride were significantly lower compared with the control group. After 6 months, all groups showed similar total MMP activity, dry mass loss, and HYP release, and CTX levels were significantly lower when the fluoride concentration was ≥24 mM. Calcium fluoride (CaF2)‐like precipitates were observed over the beams. In summary, KF significantly inhibited the catalytic activity of dentin matrix‐bound CCs but did not seem to be effective for MMP‐mediated activity. 相似文献
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We present a two-phase model for a staff planning problem in a surgical department. We consider the setting where staff, in particular nurse circulators and surgical scrub technicians, are assigned to one of different service lines, and while they can be ‘pooled’ and temporally assigned to other service line if needed, these re-assignments should belimited. In Phase I, we decide on the number of staff hours to budget for each service line, considering policies limiting staff pooling and overtime, and different demand scenarios. In Phase II, we determine how these budgeted staff hours should be allocated across potential work days and shifts, given estimated staff requirements and shift-related scheduling restrictions. We propose a heuristic to speed the model’s Phase II solution time. We implement the model using a hospital’s surgical data and compare the model’s results with the hospital’s current practices. Using a simulation model for the surgical operations, we find that our two-phase model reduces the delays caused by staff unavailability as well as staff pooling, without increasing the workforce size. Finally, we briefly describe a decision-support tool we developed with the objective of fine-tuning staff planning decisions. 相似文献
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Taysi Aysegul Erten Ercal Pinar Sismanoglu Soner 《Clinical oral investigations》2021,25(11):6393-6401
Clinical Oral Investigations - The first objective of the present study was to evaluate the tensile strength and elongation to failure of commonly used suture materials in oral surgery. As a... 相似文献
40.
Asli Inci Pinar Gencpinar Demet Orhan Gulbahar Uzun Sebahat Ozdem Anıl Aktaş Samur Senay Haspolat Özgür Duman 《Brain & development》2013
Convulsions are one of the frequently seen problems for a neurologist in the daily routine. It is difficult to distinguish the seizure from pseudo-seizure because of lack of conclusive tests. The aim of this study is to investigate the relationship between seizure types and seizure periods by studying IMA serum levels in children having seizure. Two groups were included (patients and control) in our study. The patient group consisted of the children admitted to Pediatric Emergency Care during January 2008–January 2010 with seizure and the control group consisted of healthy children. Serum Ischemia modified albumin (IMA) level in the group having seizures was 99.7 and 83.2 U/ml in the control group. In the comparison of the patient and control groups, significant differences were found between their IMA values (p = 0.000). There was a significant difference between IMA values of the group having generalized tonic–clonic seizures and those of the control group (p = 0.001). In comparison of the IMA values of the group having febrile convulsions and those of the control group, a significant difference was determined (p = 0.011). It has been shown that if the seizure was prolonged over 5 min, IMA level increased, and there was a significant difference between the groups experiencing over 5 min of seizures and the groups experiencing less than 5 min of seizures (p = 0.001). An increase in IMA levels in febrile convulsion supports the hypoxia development in the brain during the seizure. Serum IMA levels increased with the elongation of the seizure period and may be an indicator for status epilepticus. 相似文献