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1.
Oxidative stress has been implicated in the development of many neurodegenerative diseases and also responsible from aging and some cancer types. Indolic compounds are a broad family of substances present in microorganisms, plants and animals. They are mainly related to tryptophan metabolism, and present particular properties that depend on their respective chemical structures. Due to free radical scavenger and antioxidant properties of indolic derivatives such as indolinic nitroxides and melatonin, a series of 2-phenyl indole derivatives were prepared and their in vitro effects on rat liver lipid peroxidation levels, superoxide formation and DPPH stable radical scavenging activities were determined against melatonin, BHT and α-tocopherol. The compounds significantly inhibited (72–98%) lipid peroxidation at 10? 3 M. These values were similar to that observed with BHT (88%). Possible structure–activity relationships of the compounds were discussed.  相似文献   
2.
Effects of nicotine, and nicotine + vitamin E on glucose 6-phosphate dehydrogenase (G-6PD) activity in rat muscle, heart, lungs, testicle, kidney, stomach, brain and liver were investigated in vivo and in vitro on partially purified homogenates. Supplementation period was 3 weeks (n = 8 rats per group): nicotine [0.5 mg/kg/day, intraperitoneal (ip)]; nicotine + vitamin E [75 mg/kg/day, intragastric (ig)]; and control group (receiving only vehicle). The results showed that nicotine (0.5 mg/kg, ip) inhibited G-6PD activity in the lungs, testicle, kidney, stomach and brain by 12.5% (p < 0.001), 48% (p < 0.001), 20.8% (p < 0.001), 13% (p < 0.001) and 23.35% (p < 0.001) respectively, and nicotine had no effects on the muscle, heart and liver G6PD activity. Also, nicotine + vitamin E inhibited G-6PD activity in the testicle, brain, and liver by 32.5% (p < 0.001), 21.5% (p < 0.001), and 16.5% (p < 0.001) respectively, and nicotine + vitamin E activated the muscle, and stomach G-6PD activity by 36% (p < 0.05), and 20% (p < 0.001) respectively. In addition, nicotine + vitamin E did not have any effects on the heart, lungs, and kidney G-6PD activity. In addition, in vitro studies were also carried out to elucidate the effects of nicotine and vitamin E on G-6PD activity, which correlated well with in vivo experimental results in lungs, testicles, kidney, stomach, brain and liver tissues. These results show that vitamin E administration generally restores the inactivation of G-6PD activity due to nicotine administration in various rat tissues in vivo, and also in vitro.  相似文献   
3.
Yildiz  Ufuk  Kandemir  Irfan  Cömert  Füsun  Akkoç  Senem  Coban  Burak 《Molecular biology reports》2020,47(3):1563-1572
Molecular Biology Reports - Two new cytotoxic 1,8-naphthalimide derivatives have been synthesized and characterized. Their biological activities as cytotoxicity and antimicrobial activities and...  相似文献   
4.
The effects of cage fish farming on physico-chemical and bacteriological water quality in Lake Volta, Ghana, were investigated in 2013–2014. Farmed and unfarmed (control) areas of the lake were selected for monitoring. Nutrients, temperature, dissolved oxygen, conductivity, turbidity, pH, total coliforms, Pseudomonas and Vibrio spp. in the water were monitored monthly. Analyses of the water samples were carried out according to standard procedures. Physico-chemical quality of the water in both farm and control sites were within ranges typical of minimally impacted water and did not vary significantly between the two contrasting sites. The bacteriological analysis, however, revealed contamination of the lake water by fish farming. The bacterial counts at the farmed sites were significantly higher (p < 0.05) than those of the control sites, with figures at the farmed sites ranging from 132 to 1 708 cfu 100 ml?1 for total coliforms, 514 to 5 170 cfu 100 ml?1 Pseudomonas spp. and 14 to 516 cfu 100 ml?1 for Vibrio spp. The results suggested that cage fish farming has increased bacterial loads in the lake water, but has had minimal impact on its physico-chemical quality.  相似文献   
5.
Nigella sativa (NS) has been shown to have antioxidant and antiinflammatory activities in different conditions. The goal of this study was to evaluate the effects of NS on cholestatic liver injury in rats. Thirty rats were recruited in the study as follows: Group 1, Bile duct ligation (BDL) (n = 10); Group 2, BDL plus NS (n = 10); and Group 3, Sham (n = 10). Bile duct ligated group received 0.2 mL kg?1 dose of NS intraperitoneally daily throughout 14 days. Liver damage and cholestasis were determined by the biochemical and the pathologic examination. Data showed a decrease in gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities of the NS treated rats when compared with BDL group (p < 0.001 for GGT and p < 0.05 for others). The NS treated rats' tissue levels of total oxidant status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) were significantly lower than that of the BDL group (p < 0.01 for all). Increases in total antioxidant capacity (TAC) and catalase (CAT) levels were statistically significant in the NS treated rats compared to BDL group (p < 0.01 for both). On the other hand, administration of NS in the rats with biliary obstruction resulted in inhibition of necro‐inflammation. These results indicate that NS exerts a therapeutic effect on cholestatic liver injury in bile duct ligated rats possibly through attenuation of enhanced neutrophil infiltration and oxidative stress in the liver tissue. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
6.
In this study, glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP+ oxidoreductase, EC 1.1.1.49; G6PD) was purified from parsley (Petroselinum hortense) leaves, and analysis of the kinetic behavior and some properties of the enzyme were investigated. The purification consisted of three steps: preparation of homogenate, ammonium sulfate fractionation, and DEAE-Sephadex A50 ion exchange chromatography. The enzyme was obtained with a yield of 8.79% and had a specific activity of 2.146 U (mg protein)(-1). The overall purification was about 58-fold. Temperature of +4 degrees C was maintained during the purification process. Enzyme activity was spectrophotometrically measured according to the Beutler method, at 340 nm. In order to control the purification of enzyme, SDS-polyacrylamide gel electrophoresis was carried out in 4% and 10% acrylamide for stacking and running gel, respectively. SDS-polyacrylamide gel electrophoresis showed a single band for enzyme. The molecular weight was found to be 77.6 kDa by Sephadex G-150 gel filtration chromatography. A protein band corresponding to a molecular weight of 79.3 kDa was obtained on SDS-polyacrylamide gel electrophoresis. For the enzymes, the stable pH, optimum pH, and optimum temperature were found to be 6.0, 8.0, and 60 degrees C, respectively. Moreover, KM and Vmax values for NADP+ and G6-P at optimum pH and 25 degrees C were determined by means of Lineweaver-Burk graphs. Additionally, effects of streptomycin sulfate and tetracycline antibiotics were investigated for the enzyme activity of glucose-6-phosphate dehydrogenase in vitro.  相似文献   
7.
The aim of this study was to evaluate the clinical value of CEA and CA 19-9 in a potential high-risk population of subjects with gastrointestinal complaints. The basic question was whether the determination of these markers, in addition to some other clinical features in this high risk population, could be helpful in diagnosing intraabdominal cancer. Two hundred and two patients with gastrointestinal complaints underwent standard diagnostic procedures and were followed for at least one year. For every patient, CEA and CA 19-9 levels were obtained at the first examination; the evaluating physician was blinded to the marker levels. The determinants of the likelihood of cancer were evaluated by multivariate analysis. Seventeen patients were diagnosed as having intraabdominal cancers. With the presence of melena (RR = 101.63, p = 0.007), nonspecific gastrointestinal symptoms (RR = 12.54, p = 0.026), increasing age (RR = 1.09, p = 0.028) and abnormal CEA (RR = 240.79, p = 0.000), the risk of having cancer increased significantly and independently. The presence of a primary gastric complaint was associated with a lower risk of cancer in this cohort (RR = 0.01, p = 0.04). Markers were not used in the diagnostic workup. In conclusion, in patients presenting with gastrointestinal complaints, the finding of elevated CEA levels may help in the diagnosis of cancer by prompting a more extensive search for intraabdominal cancer.  相似文献   
8.
This paper presents a summary of reported cases of Serious Adverse Events (SAEs) following treatment with Mectizan® (ivermectin, Merck, Sharpe &; Dohme) in onchocerciasis mass treatment programs from January 1, 1989 to December 31, 2001 through a passive surveillance system. A total of 207 SAE cases were reported out of approximately 165 million reported treatments delivered during the period under review, giving rise to a cumulative incidence of 1 reported SAE per 800,000 reported treatments. The mean age was 40 years and 70% of the cases were males. The mean time between ivermectin intake and onset of illness was 1 day. For 57% of the cases (n = 118), that was their first exposure to ivermectin. The majority of cases were reported from Cameroon (n = 176; 85%) with peaks in the incidence of SAE reporting in 1989–1991 and 1994–1995 when the program expanded to ivermectin-naïve populations. Fifty-five percent of the cases from Cameroon (i.e. 97 out of 176 cases) were encephalopathic and were reported from the central-southern region of the country; two-thirds of these cases were 'probable' or 'possible' cases of Loa loa encephalopathy temporally related to ivermectin treatment. Reporting bias may explain some but not all of the differences in SAE reporting between the 34 onchocerciasis-endemic countries that have, or have had, mass treatment programs. Further research is needed to understand the apparent clustering of encephalopathy cases in central-southern Cameroon since L. loa infection alone probably does not explain the increased incidence of this type of SAE from this region.  相似文献   
9.
Alpha1 adrenoceptors have three subtypes and drugs interacting selectively with these subtypes could be useful in the treatment of a variety of diseases. In order to gain an insight into the structural principles governing subtype selectivity, ligand based drug design (pharmacophore development) methods have been used to design a novel 1,2,3-thiadiazole ring D analogue of the aporphine system. Synthesis and testing of this compound as a ligand on cloned and expressed human alpha1 adrenoceptors is described. Low binding affinity was found, possibly due to an unfavourable electrostatic potential distribution. Pharmacophore models for antagonists at the three adrenoceptor sites (alpha1A, alpha1B, alpha1D) were generated from a number of different training sets and their value for the design of new selective antagonists discussed. The first preliminary antagonist pharmacophore model for the alpha1D adrenoceptor subtype is also reported.  相似文献   
10.
The effect of silicon (Si) on the growth, sodium (Na), chloride (Cl), boron (B) concentrations, lipid peroxidation (MDA), membrane permeability (MP), lypoxygenase activity (LOX), proline (PRO) and H(2)O(2) accumulation, and the activities of major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT and ascorbate peroxidase, APX) of barley grown in original sodic-B toxic soil were investigated. Si applied to the sodic-B toxic soil at 70, 140 and 280 mg kg(-1) levels significantly increased Si concentrations of the plants and counteracted the deleterious effects of sodicity (Na ions) and B on shoot growth. Membrane permeability and the concentrations of H(2)O(2) and MDA increased, while PRO concentration decreased in plants grown in sodic-B toxic soil without Si. LOX activity was increased by applied Si. Compared with control plants, the activities of SOD and CAT were decreased, but APX was increased by applied Si levels.  相似文献   
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