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431.
432.
Hepatic ischemia-reperfusion (I/R) can lead to liver failure in association with remote organ damage, both of which have significant rates of morbidity and mortality. In this study, novel spin trapping and histopathological techniques have been used to investigate in vivo free radical formation in a rat model of warm liver I/R injury. 5,5-Dimethyl-1-pyrroline N-oxide (DMPO) was administered to rats via intraperitoneal injection at a single dose of 1.5g of pure DMPO/kg body wt 2h before the initiation of liver ischemia. Blood vessels supplying the median and left lateral hepatic lobes were occluded with an arterial clamp for 60min, followed by 60min reperfusion. The effects of DMPO on I/R injury were evaluated by assessing the hepatic ultrastructure via transmission electron microscopy and by histopathological scoring. Immunoelectron microscopy was performed to determine the cellular localization of DMPO nitrone adducts. Levels of nitrone adducts were also measured to determine in situ scavenging of protein and DNA radicals. Total histopathological scoring of cellular damage was significantly decreased in hepatic I/R injury after DMPO treatment. DMPO treatment significantly decreased the hepatic conversion of xanthine oxidase and 4-hydroxynonenal formation in I/R injury compared to the untreated I/R group. The distribution of gold-nanoparticle-labeled DMPO nitrone adducts was observed in mitochondria, cytoplasm, and nucleus of hepatocytes. The formation of protein- and DNA-nitrone adducts was increased in DMPO-treated I/R livers compared to DMPO controls, indicating increased in situ protein and DNA radical formation and scavenging by DMPO. These results suggest that DMPO reduces I/R damage via protection against oxidative injury.  相似文献   
433.
The aim of this study is to investigate the effect of leptin in rats on carbon tetrachloride (CCl4) induced acute liver damage using immunohistochemical methods for apoptosis and biochemical parameters. In this experimental study, 18 Spraque-Dawley rats were divided into three groups viz; control, CCl4 and CCl4+leptin treatment. 0.8 ml/kg olive oil was administered intraperitoneally (i.p.) to the control group and 0.8 ml/kg CCl4 (1:1 dissolved in olive oil) was administered i.p. to the CCl4 and CCl4+leptin treatment groups, respectively. After 6 h of administrating CCl4, CCl4+leptin treatment group was given i.p. leptin (10 μg/kg). Twenty-four hours after administrating CCl4 all of the groups were euthanized. Biochemical assessments were performed using serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), plasma tumor necrosis factor alpha (TNF-α) levels and tissue malondialdehyde (MDA), and TNF-α levels. Histological assessments were then performed using Hematoxylin&Eosin (H&E) staining in light microscope and apoptosis assessment using Terminal Transferase dUTP Nick End Labeling (TUNEL)-staining. Serum AST, ALT, ALP and plasma TNF-α levels, tissue MDA and TNF-α levels had all increased in CCl4 group, but were found to be significantly decreased in CCl4+leptin treatment group. Moreover, TUNEL-positive cell counts in liver had significantly increased in CCl4 group, but decreased in CCl4+leptin treatment group (P < 0.05). The results of our study the biochemical, histological and TUNEL-staining showed that leptin has treatment effects on liver CCl4 induced injury. It plays a role as a potent free radical scavenger, a powerful antioxidant and it also has anti-apoptotic effects.  相似文献   
434.
Hair analysis is a promising tool for routine clinical screening and diagnosis of heavy metal exposure and essential trace element status in the human body. Systemic intoxications have been identified by anomalously high values of toxins in hair samples. The aim of the present study is to evaluate the relationship between smoking habit of the family members and the levels of toxic and nontoxic trace elements in hair samples of children. The randomized cross-sectional controlled study comprised of 95 children (41 girls and 54 boys) between the ages of 1 and 6 years. After written informed consent was obtained, a face-to-face interview was conducted with the families about educational background, total income of the family, and smoking habits of family members. The mineral elements considered in this study were Zn, Se, B, V, Co, Mo, Mn, iron (Fe), Be, aluminum (Al), As, cadmium (Cd), lead (Pb), Hg, chromium (Cr), Ag, Be, nickel (Ni), copper (Cu), Sn, and antimony (Sb). Hair mineral contents were measured by inductively coupled plasma-mass spectrometry. The results showed that the levels of Cd, Pb, Cr, Sb, Fe, and Al in hair samples of children whose parents smoked were significantly higher than those whose parents were nonsmokers. The number of smokers and the frequency of smoking at home were positively correlated with Pb, Cd, Cu, Ni, and Sb levels found. At the same time, it was found that there was no correlation between toxic element concentrations and family income or educational background excluding the levels of Cd. A correlation was observed between the smoking status of family members and levels of toxic trace elements in hair where this correlation was more significant with the levels of Pb and Cd. High socioeconomic status and the level of education of family members did not have any effect on toxic trace levels in hair samples of children.  相似文献   
435.
Cyclophosphamide (CP) has potential urotoxicity such as hemorrhagic cystitis (HC). 2-Mercaptoethane sulfonate (mesna) has been widely used as an effective agent against CP-induced cystitis, but significant HC has still been encountered clinically. In recent studies, mesna was shown to be more effective if combined with antioxidants. The purpose of this study was to evaluate the effects of antioxidants, alpha-tocopherol, beta-carotene and melatonin on CP-induced bladder damage in rats, even if used without mesna administration. Male Sprague-Dawley rats weighing 180-210 g were divided into 5 groups. Four groups received a single dose of CP (100 mg/kg) intraperitoneally with the same time intervals. Group 2 received CP only, group 3 received beta-carotene (40 mg/kg/day), group 4 received alpha-tocopherol (40 mg/kg/day) and group 5 received melatonin (10 mg/kg/day) both before and the day after CP injection. Group 1 served as control. Bladder histopathology, as well as malondialdehyde (MDA) and iNOS levels, and excretion of nitrite-nitrates (NO(x)) in urine were evaluated. CP injection resulted in severe histological changes and macroscopic hematuria. alpha-Tocopherol and melatonin showed meaningful protection against bladder damage. Protection by beta-carotene was also significant but weaker. MDA levels increased significantly with CP injection and all antioxidants ameliorated this increase in bladder tissue. CP also elevated the NO(x) level in urine and iNOS activity in bladder. Only melatonin was able to decrease these parameters. In conclusion, there is no doubt that oxidants have a role in the pathogenesis of CP-cystitis. Antioxidants, especially melatonin and alpha-tocopherol, may help to ameliorate bladder damage induced by CP.  相似文献   
436.
The aim of this study was to investigate the possible relationship between serum total sialic acid (TSA) concentration, recently shown to be a cardiovascular risk factor, and lipid and protein oxidation and antioxidant status and the severity of coronary artery disease (CAD) according to the obstructive vessel number in patients. The study was carried out on a total of 200 patients (142 men and 58 women) who were hospitalized for elective coronary angiographic evaluation with complaint of typical angina pectoris. According to the results of angiography, 150 patients had angiographically proven CAD (CAD group) and 50 patients had a history suggestive of angina pectoris but normal coronary angiograms (control group). The CAD group was further divided into single-, double- and triple-vessel disease groups according to the number of vessels involved. Lipid parameters were determined by routine laboratory methods. Plasma malondialdehyde (MDA) and vitamin E concentrations were determined by high-performance liquid chromatography. TSA and other oxidant and antioxidant parameters were studied spectrophotometrically. Our results demonstrated significant increases both in TSA levels and in indicators of oxidative stress in the patients with CAD compared with the controls. However, antioxidant parameters were decreased in the patients with CAD. We found strong positive correlations between TSA and plasma MDA, Delta-MDA which represents the degree of oxidative modification of apolipoprotein B-containing lipoproteins, serum protein carbonyls and apolipoprotein B and weak correlations between TSA and low density lipoprotein cholesterol, triacylglycerol, paraoxonase, glutathione peroxidase (GPx), vitamin C and vitamin E. In conclusion, TSA is related to markers of lipid and protein oxidation, paraoxonase and GPx activities, vitamin C and E levels and the severity of CAD.  相似文献   
437.
Virus is the most menacing factor for plant, which causes enormous economic losses in agriculture worldwide. Tobacco mosaic virus is most hazardous virus among the plants that can spread through biological and non-biological sources. TMV is ancient virus that causes huge economic losses to pepper cucumber ornamental crops and tobacco. It can be controlled by reducing the population of vector through pesticide application. However, the rapid usage of synthetic chemicals causes environmental pollution and destroys our ecosystem. Consequently, different approaches just like natural derivatives should be adopted for the environmental friendly management for TMV. This in vitro study demonstrated the potential role of natural metabolites such as poultry manure and plant extracts such as salicylic acid and citric acid for the control of TMV. Two different concentrations of poultry manure 60G and 30G were used. Poultry manure was mixed with the soil at the time of sowing. Disease severity was minimum at maximum concentration as compared to the control. Meanwhile, two different concentrations of salicylic acid and citric acid 60% and 90% were applied by foliar sprayer after three-leaf stages. Disease severity was observed after 5, 10, 15, 20, 25, and 30 days after disease inoculation. Here also maximum concentration showed the minimum disease severity and higher concentration of both animal and plants extracts were used for following experiment. Quantitative real-time PCR (RT-qPCR) results demonstrated that different plant defense-related genes such as PR1a, PAL, PR5, NPR1, PRIb, and PDF1.2 were up-regulated. Furthermore, applications of each treatment-induced systemic resistance against a wide range of pathogen including TMV and fungal pathogen Botrytis cinerea.  相似文献   
438.

Aim

The purpose of the present study is to show the application of the IAEA TRS-430 QA procedures of Eclipse™v7.5 TPS for photon energies. In addition, the trends of the deviations found in the conducted tests were determined.

Background

In the past, the lack of complete TPS QA procedures led to some serious accidents. So, QA in the radiotherapy treatment planning process is essential for determination of accuracy in the radiotherapy process and avoidance of treatment errors.

Materials and methods

The calculations of TPS and measurements of irradiations of the treatment device were compared in the study. As a result, the local dose deviation values (δ1: central beam axis, δ2: penumbra and build up region, δ3: inside field, δ4: outside beam edges, δ50–90: beam fringe, RW50: radiological width) and their confidence limit values (including systematic and random errors) were obtained.

Results

The confidence limit values of δ4 were detected to increase with expanding field size. The values of δ1 and δ3 of hard wedge were larger than open fields. The values of δ2 and δ50–90 of the inhomogeneity effect test were larger, especially than other tests of this study. The average deviation was showed to increase with the rise of the wedge angle. The values of δ3 and δ4 of lung irradiation were outside tolerance.

Conclusions

The QA of TPS was done and it was found that there were no reservations in its use in patient treatment. The trend of the deviations is shown.  相似文献   
439.
440.
d-galactose (GAL) causes aging-related changes and oxidative stress in the organism. We investigated the effect of carnosine (CAR) or taurine (TAU), having antioxidant effects, on hepatic injury and oxidative stress in GAL-treated rats. Rats received GAL (300 mg/kg; s.c.; 5 days/week) alone or together with CAR (250 mg/kg/daily; i.p.; 5 days/week) or TAU (2.5 % w/w; in rat chow) for 2 months. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and hepatic malondialdehyde (MDA), protein carbonyl (PC) and glutathione (GSH) levels and superoxide dismutase (SOD), glutathione peroxidase (GSH-0050x), and glutathione transferase (GST) activities were determined. Hepatic expressions of B cell lymphoma-2 (Bcl-2), Bax and Ki-67 were evaluated. Serum ALT, AST, hepatic MDA, and PC levels were observed to increase in GAL-treated rats. Hepatic Bax expression, but not Bcl-2, increased, Ki-67 expression decreased. GAL treatment caused decreases in GSH levels, SOD and GSH-Px activities in the liver. Hepatic mRNA expressions of SOD, but not GSH-Px, also diminished. CAR or TAU treatments caused significant decreases in serum ALT and AST activities. These treatments decreased apoptosis and increased proliferation and ameliorated histopathological findings in the livers of GAL-treated rats. Both CAR and TAU reduced MDA and PC levels and elevated GSH levels, SOD and GSH-Px (non significant in TAU?+?GAL group) activities. These treatments did not alter hepatic mRNA expressions of SOD and GSH-Px enzymes. Our results indicate that CAR and TAU restored liver prooxidant status together with histopathological amelioration in GAL-induced liver damage.  相似文献   
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