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1.
Effects of subchronic exposure to zinc nanoparticles on tissue accumulation,serum biochemistry,and histopathological changes in tilapia (Oreochromis niloticus) 下载免费PDF全文
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
2.
Gokhan Koca Hakan Ozsoy Hasan Ikbal Atilgan Koray Demirel Veysel Ercan Dincel Meliha Korkmaz 《Nuclear Medicine and Molecular Imaging》2012,46(3):215-217
After surgical therapy of diffuse pigmented villonodular synovitis (DPVNS), recurrence is seen in almost half of the patients. The effectiveness of radiosynovectomy (RSV) in preventing recurrence and complaints of DPVNS is well known. Elbow involvement in DPVNS is a very rare condition; therefore, RSV in elbow hasn’t been experienced widely. The aim of this case report is to show the effectiveness of RSV with rhenium-186 (Re-186) sulfide colloid. We applied Re-186 sulfide colloid to the elbow joint of DPVNS patients six weeks after arthroscopic synovectomy. As a result, the patient did not have any complaints, and our findings are compatible with residue or recurrence on magnetic resonance imaging (MRI) in sixth and twentieth month controls after administration. We concluded that Re-186 is an effective adjuvant therapy for the prevention of recurrence and complaints. 相似文献
3.
Accumulation and toxicity of CuO and ZnO nanoparticles through waterborne and dietary exposure of goldfish (Carassius auratus) 下载免费PDF全文
Mehmet Ates Zikri Arslan Veysel Demir James Daniels Ibrahim O. Farah 《Environmental toxicology》2015,30(1):119-128
Dietary and waterborne exposure to copper oxide (CuO) and zinc oxide (ZnO) nanoparticles (NPs) was conducted using a simplified model of an aquatic food chain consisting of zooplankton (Artemia salina) and goldfish (Carassius auratus) to determine bioaccumulation, toxic effects, and particle transport through trophic levels. Artemia contaminated with NPs were used as food in dietary exposure. Fish were exposed to suspensions of the NPs in waterborne exposure. ICP‐MS analysis showed that accumulation primarily occurred in the intestine, followed by the gills and liver. Dietary uptake was lower, but was found to be a potential pathway for transport of NPs to higher organisms. Waterborne exposure resulted in about a 10‐fold higher accumulation in the intestine. The heart, brain, and muscle tissue had no significant Cu or Zn. However, concentrations in muscle increased with NP concentration, which was ascribed to bioaccumulation of Cu and Zn released from NPs. Free Cu concentration in the medium was always higher than that of Zn, indicating CuO NPs dissolved more readily. ZnO NPs were relatively benign, even in waterborne exposure (p ≥ 0.05). In contrast, CuO NPs were toxic. Malondialdehyde levels in the liver and gills increased substantially (p < 0.05). Despite lower Cu accumulation, the liver exhibited significant oxidative stress, which could be from chronic exposure to Cu ions. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 119–128, 2015. 相似文献
4.
Ünal Güntekin Hasan Ali Gümrükçüoğlu Mehmet Yaman Fatih Öztürk Aytaç Akyol Fatma Nur Gümrükçüoğlu Yunus Emre Okudan Veysel Tosun Yasemin Behram Kandemir 《Clinical therapeutics》2018,40(12):2031-2040
Purpose
Cardiovascular disease (CVD) due to atherosclerosis is the leading cause of early mortality and morbidity. The current European guidelines on CVD prevention in clinical practice recommend the use of the Systematic Coronary Risk Estimation (SCORE) system. The current American Heart Association guidelines recommend the use of the new pooled cohort risk assessment equations to estimate the 10-year atherosclerotic CVD risk. The purpose of this article was to investigate the compliance of dyslipidemia guidelines in daily practice in patients with dyslipidemia or who have risk factors for CVD.Methods
The study group consisted of 500 outpatients who had dyslipidemia or risk factors for CVD. The risk level was computed according to the European and American Heart Association guidelines. Therapeutic LDL-C targets were identified based on the calculated risk level. Therapeutic target levels were compared based on the dosage of statins used and achievement of the LDL-C goal in daily practice according to the risk levels.Findings
According to the European dyslipidemia guidelines, 231 patients were in the very-high/high-risk group, and 106 patients (45.9%) achieved the LDL-C target (<100 mg/dL); 210 patients were in the moderate-risk group, and 156 (74.3%) patients achieved the LDL-C target (<115 mg/dL); and 59 patients were in the low-risk group, and 55 (93.2%) patients achieved the LDL-C target (<155 mg/dL). Univariate and multivariate logistic regression analyses revealed that the LDL-C level and presence of coronary artery disease were significantly reverse associated with achievement of the LDL-C goal (both, P < 0.001).Implications
Our results showed that the majority of patients were in the very-high/high-risk group in daily practice. Although the European dyslipidemia guidelines are more likely to be used in daily practice, achievement of the guidelines-recommended treatment goals was low. 相似文献5.
6.
STUDY OBJECTIVE: QT dispersion (QTd) and late potentials derived from signal-averaged ECG (SAECG) have been proposed as noninvasive predictors of cardiac arrhythmias that occur in patients with COPD. In this study, we aimed to investigate QTd and SAECG in patients with COPD. DESIGN: Cross-sectional study. SETTING: Teaching chest disease hospital and cardiology center in a university hospital. PATIENTS: Thirty patients with COPD (28 men and 2 women; mean +/- SD age, 60 +/- 9 years) and 31 age- and sex-matched control subjects (28 men and 3 women; mean age, 57 +/- 7 years) were included. Measurements and results: Respiratory function tests, arterial blood gas analyses, echocardiographic examinations, rhythm Holter recordings, and heart rate variability (HRV) analyses were performed in addition to the measurements of QT intervals and SAECG. Patients with COPD had higher rate of ventricular premature beats (VPBs) as compared to control subjects (924 +/- 493 beats vs 35 +/- 23 beats, p = 0.009). Eight patients with COPD (27%) had nonsustained runs of ventricular tachycardia (VT). QTd rates were significantly increased in patients with COPD as compared to control subjects (57.7 +/- 9.9 ms vs 37.5 +/- 8.2 ms, p < 0.001). On comparing patients with COPD with and without runs of VT, patients with VT had longer QTd (67 +/- 10 ms vs 55 +/- 8 ms, p = 0.001). However no difference in any HRV and late potential parameters were found between patients with COPD with and without runs of VT. VPB rates were strongly correlated with QTd in patients with COPD (r = 0.61, p < 0.001). On SAECG analysis, patients with COPD had significantly increased total QRS duration as compared to control subjects. Nine of the 30 patients with COPD (30%) had positive late potentials. However, QTd and VPB rates were also similar between patients with COPD with and without late potentials. CONCLUSIONS: The development of ventricular arrhythmia in patients with COPD was associated with increased QTd. Increased QTd may be associated with autonomic changes seen in patients with COPD. 相似文献
7.
Tahan V Ozaras R Canbakan B Uzun H Aydin S Yildirim B Aytekin H Ozbay G Mert A Senturk H 《Journal of pineal research》2004,37(2):78-84
Increased deposition of the extracellular matrix components, particularly collagen, is a central phenomenon in liver fibrosis. Stellate cells, the central mediators in the pathogenesis of fibrosis are activated by free radicals, and synthesize collagen. Melatonin is a potent physiological scavenger of hydroxyl radicals. Melatonin has also been shown to be involved in the inhibitory regulation of collagen content in tissues. At present, no effective treatment of liver fibrosis is available for clinical use. We aimed to test the effects of melatonin on dimethylnitrosamine (DMN)-induced liver damage in rats. Wistar albino rats were injected with DMN intraperitoneally. Following a single dose of 40 mg/kg DMN, either saline (DMN) or 100 mg/kg daily melatonin was administered for 14 days. In other rats, physiologic saline or melatonin were injected for 14 days, following a single injection of saline as control. Hepatic fibrotic changes were evaluated biochemically by measuring tissue hydroxyproline levels and histopathogical examination. Malondialdehyde (MDA), an end product of lipid peroxidation, and glutathione (GSH) and superoxide dismutase (SOD) levels were evaluated in blood and tissue homogenates. DMN caused hepatic fibrotic changes, whereas melatonin suppressed these changes in five of 14 rats (P < 0.05). DMN administration resulted in increased hydroxyproline and MDA levels, and decreased GSH and SOD levels, whereas melatonin reversed these effects. When melatonin was administered alone, no significant changes in biochemical parameters were noted. In conclusion, the present study suggests that melatonin functions as a potent fibrosuppressant and antioxidant, and may be a therapeutic choice. 相似文献
8.
Tahir Karaman Sabiha Zelal Ulku Ali Ihsan Zengingul Sedat Guven Veysel Eratilla Ebru Sumer 《The journal of advanced prosthodontics》2015,7(3):257-263
PURPOSE
In this study, we aimed to evaluate the amount of marginal gap with two different substructure materials using identical margin preparations.MATERIALS AND METHODS
Twenty stainless steel models with a chamfer were prepared with a CNC device. Marginal gap measurements of the galvano copings on these stainless steel models and Co-Cr copings obtained by a laser-sintering method were made with a stereomicroscope device before and after the cementation process and surface properties were evaluated by scanning electron microscopy (SEM). A dependent t-test was used to compare the mean of the two groups for normally distributed data, and two-way variance analysis was used for more than two data sets. Pearson''s correlation analysis was also performed to assess relationships between variables.RESULTS
According to the results obtained, the marginal gap in the galvano copings before cementation was measured as, on average, 24.47 ± 5.82 µm before and 35.11 ± 6.52 µm after cementation; in the laser-sintered Co-Cr structure, it was, on average, 60.45 ± 8.87 µm before and 69.33 ± 9.03 µm after cementation. A highly significant difference (P<.001) was found in marginal gap measurements of galvano copings and a significant difference (P<.05) was found in marginal gap measurements of the laser-sintered Co-Cr copings. According to the SEM examination, surface properties of laser sintered Co-Cr copings showed rougher structure than galvano copings. The galvano copings showed a very smooth surface.CONCLUSION
Marginal gaps values of both groups before and after cementation were within the clinically acceptable level. The smallest marginal gaps occurred with the use of galvano copings. 相似文献9.
10.