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11.
The current study was conducted to determine whether there is a relation between hypertension and two different polymorphisms, including C1562T of the Matrix metalloproteinase-9 (MMP-9) gene and C677T of the methylenetetrahydrofolate reductase (MTHFR) gene. Genomic DNA obtained from 224 persons (125 patients with hypertension and 99 healthy controls) were used in the study. Polymorphisms were determined by using polymerase chain reaction-restriction fragment length polymorphism and electrophoresis. The results were statistically analyzed and were found to be statistically significant. The frequencies of the C1562T genotypes were found to be, in controls CC 75.8 % and CT 24.2 % and in patients CC 71.2 %, and CT 28.8 %. The frequencies of C677T genotype were found to be, in controls CC 56.6 %, CT 38.4 and TT 5.1 % in controls and in patients CC 52 %, CT 30.4 % and TT 17.6 %. In conclusion, we may suggest that there is no relation between the essential hypertension and C1562T polymorphism of MMP-9 gene; on the other hand C677T polymorphism (genotype TT) of MTHFR gene can be regarded as a genetic indicator for the development of essential hypertension.  相似文献   
12.
Nephronophthisis-related ciliopathies (NPHP-RC) are recessive diseases characterized by renal dysplasia or degeneration. We here identify mutations of DCDC2 as causing a renal-hepatic ciliopathy. DCDC2 localizes to the ciliary axoneme and to mitotic spindle fibers in a cell-cycle-dependent manner. Knockdown of Dcdc2 in IMCD3 cells disrupts ciliogenesis, which is rescued by wild-type (WT) human DCDC2, but not by constructs that reflect human mutations. We show that DCDC2 interacts with DVL and DCDC2 overexpression inhibits β-catenin-dependent Wnt signaling in an effect additive to Wnt inhibitors. Mutations detected in human NPHP-RC lack these effects. A Wnt inhibitor likewise restores ciliogenesis in 3D IMCD3 cultures, emphasizing the importance of Wnt signaling for renal tubulogenesis. Knockdown of dcdc2 in zebrafish recapitulates NPHP-RC phenotypes, including renal cysts and hydrocephalus, which is rescued by a Wnt inhibitor and by WT, but not by mutant, DCDC2. We thus demonstrate a central role of Wnt signaling in the pathogenesis of NPHP-RC, suggesting an avenue for potential treatment of NPHP-RC.  相似文献   
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14.
In this research, thermally dried Pseudomonas aeruginosa cells were used as a biological material for the construction of a microbial biosensor. The preparation, optimization and application of the developed microbial biosensor, which analyzed Pb(II), are presented. The method was based on stripping of adsorbed metal ions from the modified electrode surface. Modified carbon paste electrodes were preconcentrated at open circuit, and then electrochemically measured by using cyclic voltammetry (CV) and differential pulse stripping voltammetry (DPSV) techniques. It was found that the thermally dried cells were capable of adsorbing Pb(II) ions from aqueous solutions and could determine the ions prominently at optimum experimental conditions. Many important parameters to acquire the best electrochemical response were carried out, including effect of different electrolyte solutions, pH, deposition potential, deposition time, ionic strength, preconcentration time, and effect of interference ions. Finally, a calibration graph was obtained with a linear range from 1.0×10(-6) to 2.0×10(-5) M Pb(II) (R(2)=0.9916) and detection limit was found as 6.0×10(-7) M Pb(II) by using 3×S(b)/m formula. Other analytical properties of the developed microbial biosensor were also investigated. The suggested usage format of P. aeruginosa for the determination of Pb(II) does not require complicated immobilization procedure, easy to handle, and not time consuming.  相似文献   
15.
AIM: Oxytocin was previously shown to have anti-inflammatory effects in different inflammation models. The major objective of the present study was to evaluate the protective role of oxytocin (OT) in protecting the kidney against ischemia/reperfusion (I/R) injury. MATERIALS AND METHODS: Male Wistar albino rats (250-300 g) were unilaterally nephrectomized, and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. OT (1 mg/kg, ip) or vehicle was administered 15 min prior to ischemia and was repeated immediately before the reperfusion period. At the end of the reperfusion period, rats were decapitated and kidney samples were taken for histological examination or determination of malondialdehyde (MDA), an end product of lipid peroxidation; glutathione (GSH), a key antioxidant; and myeloperoxidase (MPO) activity, an index of tissue neutrophil infiltration. Creatinine and urea concentrations in blood were measured for the evaluation of renal function, while TNF-alpha and lactate dehydrogenase (LDH) levels were determined to evaluate generalized tissue damage. Formation of reactive oxygen species in renal tissue samples was monitored by chemiluminescence technique using luminol and lucigenin probes. RESULTS: The results revealed that I/R injury increased (p<0.01-0.001) serum urea, creatinine, TNF-alpha and LDH levels, as well as MDA, MPO and reactive oxygen radical levels in the renal tissue, while decreasing renal GSH content. However, alterations in these biochemical and histopathological indices due to I/R injury were attenuated by OT treatment (p<0.05-0.001). CONCLUSIONS: Since OT administration improved renal function and microscopic damage, along with the alleviation of oxidant tissue responses, it appears that oxytocin protects renal tissue against I/R-induced oxidative damage.  相似文献   
16.
The present study was aimed to investigate the effect of ACE inhibition on trinitrobenzene sulphonic acid (TNBS)-induced colonic inflammation in rats by using captopril and lisinopril. In treatment groups, the rats were treated with ACE inhibitors, captopril or lisinopril (0.1 and 1 mg/kg/day; intraperitoneally). The drugs were given 5 min after induction of colitis and the treatment was continued for 3 days. Three days after the induction of colitis, all rats were decapitated. The distal colon was weighed and the mucosal lesions were scored at both macroscopical at microscopic levels. Malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were assessed in tissue samples. Formation of reactive oxygen species in colonic samples was monitored by using chemiluminescence technique. Serum TNF-alphalevel was assessed in trunk blood. Captopril treatment was found to be beneficial in all parameters, except colonic glutathione content. On the other hand, although stimulation of lipid peroxidation and increase in serum TNF-alpha level were successfully prevented by lisinopril, the morphology of the lesions remained unchanged. In conclusion, sulphydryl and non-sulphydryl ACE inhibitors, captopril and lisinopril do not seem to be similarly effective in TNBS-induced colitis model at least at the doses tested in our study.  相似文献   
17.
Background: Sepsis is a generalized inflammatory response, which involves organ systems remote from the locus of the initial infectious insult, involves the release of cytokines and the subsequent formation of reactive oxygen and nitrogen species.Objective: The aim of this study was to investigate the possible protective effect of montelukast, a leukotriene receptor blocker, against oxidative damage in the liver and ileum of septic rats.Methods: Sepsis was induced by cecal ligation and puncture method in female Wistar albino rats. Sepsis and sham operated (control) groups received either saline or montelukast (10 mg/kg, ip) immediately after the operation and at 12 h. Twenty-four hours after the surgery, rats were decapitated and malondialdehyde (MDA) content—an index of lipid peroxidation, glutathione (GSH) levels—a key antioxidant, myeloperoxidase (MPO) activity—an index of neutrophil infiltration, and collagen contents were determined in the liver and ileum. Formation of reactive oxygen species in liver and ileal tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probes. Both tissues were also analyzed histologically. Serum lactate dehydrogenase (LDH) and tumor necrosis factor-α (TNF-α) level were assessed in trunk blood.Results: Sepsis resulted in decreased GSH levels, and increased MDA levels, MPO activity, CL levels and collagen contents in both the liver and the ileum (P<0.05–P<0.001) indicating the presence of the oxidative damage. Similarly, serum TNF-α and LDH were elevated in the sepsis group as compared to control group. On the other hand, montelukast treatment reversed all these biochemical indices, as well as histopathological alterations, which were induced by sepsis.Conclusion: Findings of the present study suggest that montelukast possesses an anti-inflammatory effect on sepsis-induced hepatic and intestinal damage and protects against oxidative injury by a neutrophil-dependent mechanism.  相似文献   
18.
The antimicrobial activity and the MIC values of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Hypogymnia tubulosa and its 3-hydroxyphysodic acid constituent have been investigated against some microorganisms. At least one of the extracts or 3-hydroxyphysodic acid showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Proteus vulgaris, Salmonella typhimurium, Staphylococcus aureus, Streptococcus faecalis, and Candida albicans. No antifungal activity of the extracts has been observed against ten filamentous fungi.  相似文献   
19.
Taşkin V  Kence M  Göçmen B 《Genetika》2004,40(4):478-481
Organophosphate (OP) insecticides (parathion/diazinon) resistance in housefly (Musca domestica L.) is associated with the change in carboxylesterase activity. The product of alpha E7 gene, which is a member of alpha-esterase gene cluster, is probably playing a role in detoxification of the xenobiotic esters. In parathion/diazinon resistant M. domestica species Gly137 to Asp substitution was found in the active center of the product of alpha E7 gene. In malathion (an OP) resistant M. domestica strains Trp251 to Ser substitution was identified in the active center of the Md alpha E7. In our research, to understand the allelic diversity of the Md alpha E7, the gene was partially sequenced from four different housefly strains from different localities (Guatemala, Manhattan (USA), Colombia (USA) and Thailand). It was found out that; in Thailand strain one allele has Cys residue at the position of 251, the other allele contains a Trp for the same site. In Colombia strain, one allele has Asp137, the other allele contains a Gly residue at this point. The Manhattan and Guatemala strains have Asp137 and Trp251 residues on their both alleles at these two different positions.  相似文献   
20.
The neuroprotective effect of alpha lipoic acid (ALA; 100 mg/kg, po), a dithiol antioxidant, on experimentally induced subarachnoid hemorrhage (SAH) was assessed in Wistar albino rats. Neurological examination scores recorded at the 48th h of SAH induction were increased in SAH groups, which were accompanied with significant increases in the formation of reactive oxygen species, DNA fragmentation ratios, malondialdehyde levels and myeloperoxidase activity, while significant decreases in the brain glutathione content and Na+, K+-ATPase activity were observed. On the other hand, ALA treatment reversed all these biochemical indices as well as SAH-induced histopathological alterations. Increased brain edema, impaired blood-brain-barrier permeability and neurological scores were also improved by ALA treatment. The results demonstrate that ALA exerts neuroprotective effects via the enhancement of endogenous antioxidant enzyme activity, the inhibition of neutrophil accumulation and free radical generation, suggesting a therapeutic potential in reducing secondary injury after SAH in patients.  相似文献   
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