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101.
The Genotoxic Effect of the New Acaricide Etoxazole 总被引:2,自引:1,他引:1
Rencüzogğullari E. Basriİla H. Kayraldiz A. Arslan M. Budak Diler S. Topaktas¸ M. 《Russian Journal of Genetics》2004,40(11):1300-1304
Etoxazole is a member of the diphenyl oxazoline class of insecticide, which was newly developed for use on pome fruits, cotton and strawberries as an acaricide. In the present study, genotoxic effects of acaricide etoxazole (ETX) (miticide/ovicide) were investigated using chromosome aberration (CA) test, sister chromatid exchange (SCE) test, and micronucleus test in human lymphocytes. ETX induced the CAs at all concentrations (5, 10, and 20 g/ml) for 24 h and also induced the CA at the highest concentration (20 g/ml) for 48 h only. The inducing the CAs for 48 h treatment period was dose-dependent. In addition, it induced the SCE at all concentrations and treatment periods in a dose-dependent manner as well. Although ETX decreased the mitotic index (MI) at all concentrations and treatment periods dose-dependently, it did not decrease the replication index (RI) when compared to the negative and solvent controls. In addition, ETX induced the micronucleus at all concentrations except 5 g/ml for 48 h. This inducing was dose-dependent as well. It can be concluded that ETX has a potential genotoxic effects in cultured human peripheral lymphocytes. 相似文献
102.
Chronic inflammation is a common feature of end-stage renal disease, which carries a heightened risk of atherosclerosis and other co-morbid conditions. Dialysis treatment per se can bring additional risk factors for inflammation, such as increased risk of local graft and fistula infections, impure dialysate or bio-incompatible membranes. Our study was designed to determine whether a hemodialysis session leads to an acute substantial alteration in the plasma levels of the proinflammatory cytokines interleukin (IL)-6, IL-1beta and tumor necrosis factor (TNF)-alpha, the T-lymphocyte activation factor soluble IL-2 receptor (sIL-2R), and an inflammation mediator and chemotactic granulocyte factor, IL-8, in end-stage renal disease patients receiving chronic intermittent HD. In this study, 21 (12 male/nine female) patients undergoing chronic hemodialysis were enrolled. The acute effect of a hemodialysis session on serum cytokine concentrations was assessed by comparison of pre-hemodialysis and post-hemodialysis determinations. Serum IL-1beta, sIL-2R, IL-6, IL-8 and TNF-alpha levels were determined with chemiluminescence enzyme immunometric assays. A significant difference was not observed for IL-1beta, IL-6, TNF-alpha, and sIL-2R concentrations in pre-hemodialysis and post-hemodialysis specimens (p>0.05). Serum median (25th-75th percentiles) IL-8 concentration was 69.4 (34.9-110.3) pg/ml before hemodialysis, and decreased to 31.5 (18.0-78.8) pg/ml following hemodialysis (p: 0.006). Clearance of IL-8 increased by 0.47+/-0.08 pg/ml for each unit increase in pre-dialysis IL-8 (p<0.001) and decreased by 5.63+/-2.59 pg/ml for each unit increase in pre-dialysis urea mmol/l (p<0.05). In conclusion, the results of our study demonstrate that a hemodialysis session markedly decreases IL-8 concentration, which is significantly affected by pre-dialysis concentrations, indicating that removal of IL-8 is a concentration gradient-dependent action, but does not change the serum levels of IL-1beta, sIL-2R, IL-6, and TNF-alpha, underlining importance of the structural characteristics of the molecules. 相似文献
103.
Balci S Bostanoğlu S Altinok G Beksaç MS 《Genetic counseling (Geneva, Switzerland)》2003,14(4):373-377
Familial intestinal polyatresia (FIPA) is a rare autosomal recessive disorder. In this article we present a new prenatally diagnosed case with FIPA from consanguineous parents with two affected daughters. The fourth pregnancy was diagnosed prenatally with FIPA at 18 weeks sonographically and these findings were confirmed by postmortem examination. 相似文献
104.
Melatonin and N-acetylcysteine have beneficial effects during hepatic ischemia and reperfusion 总被引:18,自引:0,他引:18
Sener G Tosun O Sehirli AO Kaçmaz A Arbak S Ersoy Y Ayanoğlu-Dülger G 《Life sciences》2003,72(24):2707-2718
This study was designed to study the effects of Melatonin (Mel) and N-Acetylcystein (NAC) on hepatic ischemia/reperfusion (I/R) injury in rats. For this purpose Wistar albino rats were subjected to 45 minutes of hepatic ischemia followed by 60 minutes of reperfusion period. Melatonin (10 mg/kg) or NAC (150 mg/kg) were administered alone or in combination, intraperitoneally, 15 minutes prior to ischemia and just before reperfusion. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were determined to assess liver functions. Liver tissues were taken for determination of malondialdehyde (MDA) levels, an end product of lipid peroxidation; glutathione (GSH) levels, a key antioxidant; protein carbonyl concentration (protein oxidation) (PO), a specific marker of oxidative damage of proteins; and myeloperoxidase (MPO) activity, as an indirect index of neutrophil infiltration. Plasma ALT and AST activities were higher in ischemia/reperfusion group than in control. They were decreased in the groups given Mel, NAC or the combination. Hepatic GSH levels, significantly depressed by I/R, were elevated to control levels in the combination group, whereas treatment with Mel or NAC alone provided only a limited protection. Hepatic MDA and PO levels, and MPO activity were significantly increased by I/R. The increase in these parameters were partially decreased by Mel or NAC alone, whereas treatment with the combination reduced these values back to control levels. In conclusion, considering the dosages used, Mel appeared to be significantly more potent than NAC in reversing the oxidative damage induced by I/R. Our findings show that Mel and NAC have beneficial effects against the I/R injury and due to their synergistic effects, when administered in combination, may have a more pronounced protective effects on the liver. 相似文献
105.
Contractile responses of the human umbilical artery to KCl and serotonin in Ca-free medium and the effects of levcromakalim 总被引:2,自引:0,他引:2
It is known that K(ATP) channel openers inhibit the release and refilling of Ca(2+) from intracellular stores. The present study was designed to test the effects of levcromakalim in human umbilical artery (HUA) rings stimulated by serotonin (5-HT) and KCl in Ca-free medium. Umbilical cords were obtained at vaginal or cesarean deliveries from healthy, term pregnancies. After the isolation, HUA rings were placed in organ baths in solution with indomethacin (10(-5) M) and N(G)-nitro-L-arginine methyl ester (L-NAME) (10(-3) M) at 37 degrees C and aerated with 95% O(2) and 5% CO(2) for the measurement of isometric force. In Ca-free solution with Ethylene glycol-bis (ss-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) (2 mM) the contractions produced by 5-HT (10(-6) M) and KCl (40 mM) decreased significantly. Afterwards, HUA rings were treated with 5-HT and KCl in repeated manner in Ca-free medium. In contrast to KCl, 5-HT induced contractions reduced in each application, progressively. Levcromakalim (10(-4) M) abolished the contractions elicited by 5-HT. On the other hand, levcromakalim had a little but significant inhibitory effect on KCl induced contraction in Ca-free medium. These results suggest that Ca(2+) is not the only transduction pathway in KCl produced contractions of HUA smooth muscle cells. 相似文献
106.
This study was designed to study the effects of the potential radioprotective properties of pharmacological doses of melatonin against organ damage induced by whole-body irradiation (IR) in rats. A total of 32 male Sprague-Dawley rats were exposed to irradiation performed with a LINAC producing 6 MV photons at a focus 100 cm distant from the skin. Under ketamine anaesthesia, each rat received a single whole-body dose of 800 cGy. Immediately before and after IR, rats were treated with either saline or melatonin (20 mg/kg and 10 mg/kg, i.p.) and decapitated at 12-h after exposure to irradiation. Another group of rats was followed for 72-h after IR, where melatonin (10 mg/kg, i.p.) injections were repeated once daily. Tissue levels of malondialdehyde (MDA)--an index of lipid peroxidation--, glutathione (GSH)--a key to antioxidant--and myeloperoxidase (MPO) activity--an index of neutrophil infiltration--were estimated in liver, lung, colon and intestinal tissues. The results demonstrate that both 12-h and 72-h following IR, tissue levels of MDA were elevated (p<0.05-0.001), while GSH levels were reduced (p<0.05-0.001) in all organs. On the other hand, melatonin, reduced the levels of MDA and increased the GSH levels significantly, (p<0.05-0.001). MPO activity was increased significantly in the colonic tissue at the both 12-h and 72-h, and in the hepatic tissue at the 72-h following IR, which were reduced by melatonin (p<0.01-0.001). In the lung tissue enzyme activity was decreased at 72nd h of post-irradiation. In conclusion, the increase in MDA levels and MPO activity and the concomitant decrease in GSH levels demonstrate the role of oxidative mechanisms in irradiation-induced tissue damage, and melatonin, by its free radical scavenging and antioxidant properties, ameliorates irradiation-induced organ injury. Thus, supplementing cancer patients with adjuvant therapy of melatonin may have some benefit for successful radiotherapy. 相似文献
107.
We use the well-known structural and functional properties of the gramicidin A channel to test the appropriateness of force fields commonly used in molecular dynamics (MD) simulations of ion channels. For this purpose, the high-resolution structure of the gramicidin A dimer is embedded in a dimyristoylphosphatidylcholine bilayer, and the potential of mean force of a K(+) ion is calculated along the channel axis using the umbrella sampling method. Calculations are performed using two of the most common force fields in MD simulations: CHARMM and GROMACS. Both force fields lead to large central barriers for K(+) ion permeation, that are substantially higher than those deduced from the physiological data by inverse methods. In long MD simulations lasting over 60 ns, several ions are observed to enter the binding site but none of them crossed the channel despite the presence of a large driving field. The present results, taken together with many earlier studies, highlights the shortcomings of the standard force fields used in MD simulations of ion channels and calls for construction of more appropriate force fields for this purpose. 相似文献
108.
Koçer U Aksoy HM Tiftikcioğlu YO Cöloğlu H Karaaslan O 《Genetic counseling (Geneva, Switzerland)》2001,12(4):341-346
Report of two cases with Van der Woude syndrome: a child and her mother: Congenital pits of the lower lip are rare malformations. They are closely associated with cleft lip (CL), cleft lip/palate (CL/CP) or isolated cleft palate (CP) and if so this condition is known as Van der Woude syndrome, which is inherited in an autosomal dominant fashion with high penetrance. Two individuals, one with lower lip pits and cleft palate and the other with isolated lower lip pit from the same family are described. Autosomal dominant pattern of inheritance was observed in this family and treatment consisted of complete removal of sinus tracts in one patient. Pathological features of sinus tracts consisted of stratified nonkeratinized squamous epithelium and a lamina propria of dense connective tissue. Importance of genetic counseling is emphasized as at least half of gene carriers have some kind of clefting. 相似文献
109.
110.