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91.
The genotoxic effects of a particular mixture of acetamiprid (Acm, neonicotinoid insecticide) and α‐cypermethrin (α‐cyp, pyrethroid insecticide) on human peripheral lymphocytes were examined in vitro by chromosomal aberrations (CAs), sister chromatid exchange (SCE), and micronucleus (MN) tests. The human peripheral lymphocytes were treated with 12.5 + 2.5, 15 + 5, 17.5 + 7.5, and 20 + 10 μg/mL of Acm+α‐cyp, respectively, for 24 and 48 h. The mixture of Acm+α‐cyp induced the CAs and SCEs at all concentrations and treatment times when compared with both the control and solvent control and these increases were concentration‐dependent in both treatment times. MN formation was significantly induced at 12.5 + 2.5, 15 + 5, 17.5 + 7.5, μg/mL of Acm+α‐cyp when compared with both controls although these increases were not concentration‐dependent. Binuclear cells could not be detected sufficiently in the highest concentration of the mixture (20 + 10 μg/mL) for both the 24‐ and 48‐h treatment times. Mitotic index (MI), proliferation index (PI) and nuclear division index (NDI) significantly decreased because of the cytotoxic and cytostatic effects of the mixture, at all concentrations for two treatment periods. Significant decreases in MI and PI were concentration dependent at both treatment times. The decrease in NDI was also concentration‐dependent at 48‐h treatment period. In general, Acm+α‐cyp inhibited nuclear division more than positive control, mitomycin C (MMC) and showed a higher cytostatic effect than MMC. Furthermore, in this article, the results of combined effects of Acm+α‐cyp were compared with the results of single effects of Acm or α‐cyp (Kocaman and Topaktas, 2007 , 2009 , respectively). In conclusion, the particular mixture of Acm+α‐cyp synergistically induced the genotoxicity/cytotoxicity in human peripheral blood lymphocytes. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2010. 相似文献
92.
Remzi?AvciEmail author Berkant?Kaderli Berrin?Avci Saban?Simsek Mehmet?Baykara Zeynep?Kahveci Oner?Gelisken Ahmet?Ali?Yucel 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2004,242(10):845-852
Background To evaluate the results of pars plana vitrectomy with peeling of the internal limiting membrane (ILM) in eyes with chronic macular oedema.Methods PPV with indocyanine green (ICG) assisted peeling of the ILM was performed in 33 eyes with diabetic (21 eyes) or non-diabetic (12 eyes) macular oedema. Postoperatively, resolution of macular oedema, improvement of visual acuity (VA) and complications were documented. The peeled membranes were submitted for light and transmission electron microscopic evaluation.Results The mean follow-up time was 12.2 months. The macular oedema decreased or was resolved in 17 (81%) eyes in the diabetic group and in 11 (92%) eyes in the non-diabetic group. VA improved by at least 2 lines in 11 (52%) eyes in the diabetic group and in 7 (58%) eyes in the non-diabetic group. The difference between visual acuity improvements of the two groups was not statistically significant (P>0.05). However, in the diabetic group the difference of visual improvement between cystoid and diffuse type of macular oedema eyes was statistically significant (14% versus 71%, P=0.02). Light and transmission electron microscopy showed the presence of ILM in all specimens. During the follow-up period no recurrence of macular oedema or epiretinal membrane formation was observed.Conclusion Pars plana vitrectomy with peeling of the ILM and epiretinal membrane leads to the resolution of macular oedema in the majority of eyes. This however, is not always associated with VA improvement. In diabetic eyes, cystoid type of macular oedema appears to be a poor prognostic factor for improved VA. 相似文献
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95.
Mehmet I. Buget Nur Canbolat Chasan M. Chousein Taha Kizilkurt Ali Ersen Kemalettin Koltka 《Medicine》2022,101(27)
Supracondylar humeral fractures are seen in children and treatment is usually closed reduction and percutaneous pinning (CRPP). This surgery can be performed at night, depending on its urgency. Fatigue and sleep deprivation can impact performance of doctors during night shifts. The purpose of this study is to investigate the association between night shifts postoperative morbidity and mortality of supracondylar fracture operations compared to daytime procedures.This prospective observational study included 94 patients who were aged 5 to 12 years with ASA I to III who had supracondylar humeral fractures, underwent CRPP under general anesthesia. Patients were stratified by the time of surgery using time of induction of anesthesia as the starting time of the procedure, into 2 groups: day (07:30 am–06:29 pm) and night (06:30 pm–07:29 am). In total, 82 patients completed the study: 43 in Group Day and 39 in Group Night.The operation duration in Group Night (114.66 ± 29.46 minutes) was significantly longer than in Group Day (84.32 ± 25.9 minutes) (P = .0001). Operation duration (OR: 0.007; P = .0001) and morbidities (OR: 0.417; P = .035) were independent risk factors in Group Night.Children who had supracondylar humeral fractures, undergoing urgent CRPP surgery, in-hospital mortality was associated with the time of day at which the procedure was performed. Patient safety is critically important for pediatric traumatic patient population. Therefore, we suggested to increase the number of healthcare workers and improve the education and experience of young doctors during night shifts. 相似文献
96.
Effects of subchronic exposure to zinc nanoparticles on tissue accumulation,serum biochemistry,and histopathological changes in tilapia (Oreochromis niloticus)
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Hasan Kaya Müge Duysak Mehmet Akbulut Sevdan Yılmaz Mert Gürkan Zikri Arslan Veysel Demir Mehmet Ateş 《Environmental toxicology》2017,32(4):1213-1225
Zinc nanoparticles (ZnNPs) are among the least investigated NPs and thus their toxicological effects are not known. In this study, tilapia (Oreochromis niloticus) were exposed to 1 and 10 mg/L suspensions of small size (SS, 40–60 nm) and large size (LS, 80–100 nm) ZnNPs for 14 days under semi‐static conditions. Total Zn levels in the intestine, liver, kidney, gill, muscle tissue, and brain were measured. Blood serum glucose (GLU), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), and lactate dehydrogenase (LDH) were examined to elucidate the physiological disturbances induced by ZnNPs. Organ pathologies were examined for the gills, liver, and kidney to identify injuries associated with exposure. Significant accumulation was observed in the order of intestine, liver, kidney, and gills. Zn levels exhibited time‐ and concentration‐dependent increase in the organs. Accumulation in kidney was also dependent on particle size; NPs SS‐ZnNPs were trapped more effectively than LS‐ZnNPs. No significant accumulation occurred in the brain (p > 0.05) while Zn levels in muscle tissue increased only marginally (p ≥ 0.05). Significant disturbances were noted in serum GOT and LDH (p < 0.05). The GPT levels fluctuated and were not statistically different from those of controls (p > 0.05). Histopathological tubular deformations and mononuclear cell infiltrations were observed in kidney sections. In addition, an increase in melano‐macrophage aggregation intensity was identified on the 7th day in treatments exposed to LS‐ZnNPs. Mononuclear cell infiltrations were identified in liver sections for all treatments. Both ZnNPs caused basal hyperplasia in gill sections. Fusions appeared in the gills after the 7th day in fish treated with 10 mg/L suspensions of SS‐ZnNPs. In addition, separations in the secondary lamella epithelia were observed. The results indicated that exposure to ZnNPs could lead to disturbances in blood biochemistry and cause histopathological injuries in the tissues of O. niloticus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1213–1225, 2017. 相似文献
97.
Fatma Yildiztekin Ebru Erol Mahmut Yildiztekin Atilla L. Tuna Mehmet Ozturk 《Pharmaceutical biology》2016,54(9):1557-1563
Context We report the first ever chemical/biochemical study on Crocus mathewii Kerndorff (Iridaceae) – a Turkish endemic angiosperm. This plant has never been explored for its phytochemistry and bioactivities.Objective This study explores C. mathewii corm and aerial parts for the chemical and biological properties of hexane, ethyl acetate, methanol and water fractions of the extracts.Material and methods Plant material (20 g) was extracted by methanol (250?mL?×?5, 3 days each) and fractioned into hexane, ethyl acetate, methanol and water. All fractions were subjected to β-carotene–linoleic acid, DPPH·, ABTS·+, CUPRAC, metal chelating and tyrosinase inhibition activities. Hexane fractions were submitted to GC–MS analysis.Results Ethyl acetate fractions showed excellent IC50 values in DPPH· (aerial 36.21?±?0.76 and corm 33.87?±?0.02?mg/L) and ABTS·+ (aerial 33.01?±?0.79 and bulb 27.87?±?0.33?mg/L); higher than the IC50 of the standard α-tocopherol (DPPH 116.25?±?1.97; ABTS 52.64?±?0.37?mg/L), higher than BHA in DPPH (57.31?±?0.25?mg/L), but slightly lower in ABTS (19.86?±?2.73?mg/L). Methanol extract of aerial parts also showed higher activity than α-tocopherol in DPPH (85.56?±?11.51?mg/L) but slightly less (72.90?±?3.66?mg/L) than both the standards in ABTS. Linoleic (aerial 53.9%, corm 43.9%) and palmitic (aerial 22.2%, corm 18%) were found as the major fatty acids.Discussion and conclusion Some fractions of C. mathewii showed higher antioxidant activities than the standards. There is a need to explore more about this plant. 相似文献
98.
Budancamanak M Kanter M Demirel A Ocakci A Uysal H Karakaya C 《Archives of toxicology》2006,80(11):768-776
The goal of this investigation was to study the protective effects of thymoquinone (TQ) and methotrexate (MTX) on collagen-induced arthritis (CIA) in rats. On day 0 under ether anesthesia, the experimental groups were immunized with 0.5 mg native chick collagen II (CII) solubilized in 0.1 M acetic acid and emulsified in Freund's incomplete adjuvant. Control rats were gavaged with vehicle, whereas CII was administered intradermally. In addition, arthritis treated with TQ group received TQ (10 mg kg(-1) bw by gavage once a week for 3 weeks starting on day 0); and arthritis treated with MTX group received MTX (MTX was suspended in corn oil and administered by gavage at 1 mg kg (-1) bw once a week for 3 weeks starting on day 0). A significant decrease in the incidence and severity of arthritis by clinical and radiographic assessments was found in recipients of therapy, compared with that of controls. The MTX treatment significantly (P<0.01) decreased the elevated serum NO, urea and creatinine in arthritic rats. Likewise, TQ treatment was also able to reduce significantly (P<0.05) serum NO, urea and creatinine levels, but to lesser extent than MTX. The histopathologic abnormalities are consistent with the hydropic epithelial cell degenerations and moderate tubular dilatation in the some proximal and distal tubules. The severity of the degenerative changes in most of the shrunken glomerules and vascular congestion were also observed in arthritic animals. Preventive treatment of TQ and especially MTX significantly inhibited kidney dysfunction and this histopathologic alterations. These studies indicate that TQ can be used similar to MTX as a safe and effective therapy for CIA and may be useful in the treatment of rheumatoid arthritis. 相似文献
99.
Mehmet Unlu Emel Ergene Gulhan Vardar Unlu Hulya Sivas Zeytinoglu Nilufer Vural 《Food and chemical toxicology》2010
The essential oil from the bark of Cinnamomum zeylanicum Blume was analyzed by GC–MS and bioassays were carried out. Nine constituents representing 99.24% of the oil were identified by GC–MS. The major compounds in the oil were (E)-cinnamaldehyde (68.95%), benzaldehyde (9.94%) and (E)-cinnamyl acetate (7.44%). The antimicrobial activity of the oil was investigated in order to evaluate its efficacy against 21 bacteria and 4 Candida species, using disc diffusion and minimum inhibitory concentration methods. The essential oil showed strong antimicrobial activity against all microorganisms tested. The cytotoxic and apoptotic effects of the essential oil on ras active (5RP7) and normal (F2408) fibroblasts were examined by MTT assay and acridine orange/ethidium bromide staining, respectively. The cytotoxicity of the oil was quite strong with IC50 values less than 20 μg/mL for both cell lines. 5RP7 cells were affected stronger than normal cells. Morphological observation of apoptotic cells indicated the induction of apoptosis at the high level of the oil, especially in 5RP7 cells. The present study showed the potential antimicrobial and anticarcinogenic properties of the essential oil of cinnamon bark, indicating the possibilities of its potential use in the formula of natural remedies for the topical treatment of infections and neoplasms. 相似文献
100.
Intraocular pressure measurement over soft contact lens by rebound tonometer:a comparative study
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AIM: To evaluate the intraocular pressure (IOP) measurements by Icare rebound tonometer over a contact lens in comparison with Goldmann applanation tonometry (GAT).METHODS: Fifty patients using contact lens were included in this study. One of the eyes of the patients was selected randomly and their IOP were measured by rebound tonometer with and without contact lens (RTCL, RT respectively) and by GAT, as well as their central corneal thickness (CCT) by optical pachymeter. The results of both methods were compared by correlation analysis, general linear method repeated measure and Bland-Altman analysis.RESULTS: Mean IOP values measured by RTCL, RT and GAT were 15.68±3.7, 14.50±3.4 and 14.16±2.8 (P<0.001), respectively. Mean IOP by RTCL was significantly higher than the measurements implemented by RT and GAT (P<0.001), while there was no difference between the measurements by GAT and RT (P=0.629). There was a good level of positive correlation between GAT and RTCL as well as RT (r=0.786 P<0.001, r=0.833 P<0.001, respectively). We have observed that CCT increase did not show any correlation with the differences of the measurements between RTCL and RT (P=0.329), RTCL and GAT (P=0.07) as well as RT and GAT (P=0.189) in linear regression model.CONCLUSION: The average of the measurements over contact lens by rebound tonometer was found to be higher than what was measured by GAT. Although this difference is statistically significant, it may be clinically negligible in the normal population. 相似文献