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131.
Serum γ-glutamyltransferase (GGT) is associated with oxidative stress and hepatic steatosis. The extent to which its value in determining incident cardiometabolic risk (coronary heart disease (CHD), metabolic syndrome (MetS), hypertension and type 2 diabetes) is independent of obesity needs to be further explored in ethnicities. After appropriate exclusions, a cohort of 1,667 adults of a general population (age 52 ±11 years) was evaluated prospectively at 4 year's follow-up using partly Cox proportional hazard regressions. GGT activity was measured kinetically, and values were log-transformed for analyses. MetS was identified by Adult Treatment Panel-III criteria modified for male abdominal obesity. Median (interquartile range) GGT activity was 24.9 (17.0; 35.05) U/l in men, 17.0 (12.3; 24.0) U/l in women. In linear regression analysis, while smoking status was not associated, (male) sex, sex-dependent age, alcohol usage, BMI, fasting triglycerides and C-reactive protein (CRP) were significant independent determinants of circulating GGT. Each 1-s.d. increment in (= 0.53 ln GGT) GGT activity significantly predicted in each sex incident hypertension (hazard ratio (HR) 1.20 (95% confidence interval (CI) 1.10; 1.31)), and similarly MetS, after adjustment for age, alcohol usage, smoking status, BMI and menopause. Strongest independent association existed with diabetes (HR 1.3 (95% CI 1.1; 1.5)) whereas GGT activity tended to marginally predict CHD independent of total bilirubin but not of BMI. Higher serum total bilirubin levels were protective against CHD risk in women. We conclude that elevated serum GGT confers, additively to BMI, risk of hypertension, MetS, and type 2 diabetes but only mediates adiposity against CHD risk. 相似文献
132.
Gamze Bora-Tatar Didem Dayangaç-Erden Ayhan S. Demir Sevim Dalkara Kemal Yelekçi Hayat Erdem-Yurter 《Bioorganic & medicinal chemistry》2009,17(14):5219-5228
In the light of known HDAC inhibitors, 33 carboxylic acid derivatives were tested to understand the structural requirements for HDAC inhibition activity. Several modifications were applied to develop the structure–activity relationships of carboxylic acid HDAC inhibitors. HDAC inhibition activities were investigated in vitro by using HeLa nuclear extract in a fluorimetric assay. Molecular docking was also carried out for the human HDAC8 enzyme in order to predict inhibition activity and the 3D poses of inhibitor–enzyme complexes. Of these compounds, caffeic acid derivatives such as chlorogenic acid and curcumin were found to be highly potent compared to sodium butyrate, which is a well-known HDAC inhibitor. 相似文献
133.
Two 14-day-old seedlings of maize (Zea mays L.) cultivars (3223 and Vero) were exposed to different concentrations of lead [0, 2, 5 and 8 mM Pb(NO3)2·4H2O] for 8 days. Exposure of maize cultivars to excess Pb resulted in a significant root growth inhibition though shoot growth
and absolute water content remained less affected. The results of chlorophyll a fluorescence indicated that the highly toxic Pb level affected photochemical efficiency in 3223, while no significant effect
was observed in the Vero. At the highly toxic Pb concentration, higher membrane leakage was observed in 3223 leaves than that
of Vero. This result was related to the accumulation of Pb. On the other hand, the results suggested that there were similar
responses in total soluble POD and GR activities with increasing Pb concentrations between both cultivars. But APX activity
significantly decreased at highly toxic Pb level in the Vero while a significant increase observed in the 3223. However, SOD
activity in 3223 significantly decreased at the highly toxic Pb concentration compared with that at 2 mM Pb concentration.
The results of the present study indicated that, Vero withstands excess Pb with its higher Pb accumulation capacity in roots
and better upregulated protective mechanisms compared to 3223. Therefore, Vero is more tolerant to Pb toxicity compared to
3223 which was found to be a less tolerant cultivar. 相似文献
134.
In our study, the protective effects of vitamin E and Se (selenium) against cigarette smoke hazards on second-hand smoker (passive smoker) male mice (Balb/c) were investigated. Serum MDA levels in the smoke-exposed mice were found higher than serum MDA levels of control mice and Se- and vitamin E-treated mice. But, the MDA levels of smoke-exposed plus Se- and vitamin E-treated mice were found lower than MDA levels of smoke-exposed mice at the end of the three and five months. According to these results, application of vitamin E and Se, when given to smoke-exposed mice together, had an additive protective effect against cigarette smoke hazards (p < 0.05). Vitamin E also had protective effect on formation of 8-OHdG in smoke-exposed mice. The serum 8-OHdG amounts of smoke-exposed plus vitamin E-treated mice were found low, but the serum 8-OHdG amounts of smoke-exposed mice were found high. Also 8-OHdG levels in the serum of the smoke-exposed mice were increased which occurs as a result of DNA oxidation (p < 0.05). At the end of the three and five months, COMT (catechol-o-methyl transferase) activity of smoke-exposed mice livers were increased but, vitamin E and/or Se showed a significant protective effect on changing of COMT activity only at the end of the 5 months. Our results showed that MDA levels and 8-OHdG amounts were increased in the serum of smoke-exposed mice. On the other hand, vitamin E and Se had an additive protective effect against increasing MDA level. Also vitamin E had a protective effect against formation of 8-OHdG amounts and COMT activity alterations. 相似文献
135.
Neuroprotective Effect of Etomidate in the Central Nervous System of Streptozotocin-Induced Diabetic Rats 总被引:1,自引:0,他引:1
Ates O Yucel N Cayli SR Altinoz E Yologlu S Kocak A Cakir CO Turkoz Y 《Neurochemical research》2006,31(6):777-783
It is well known that hyperglycaemia due to diabetes mellitus leads to oxidative stress in the central nervous system. Oxidative stress plays important role in the pathogenesis of neurodegenerative changes. In the present study we investigated the possible neuroprotective effect of etomidate against streptozotocin-induced (STZ-induced) hyperglycaemia in the rat brain and spinal cord. A total of 40 rats were used in this study. Rats were divided into four groups: sham-control, diabetic, diabetic-etomidate treated and vehicle for etomidate treatment group. Diabetes mellitus was induced by a single injection of streptozotocin (60 mg/kg body weight). Three days after streptoztocin injection, etomidate (2 mg/kg) was injected intraperitoneally for etomidate group and lipid emulsion (10%) for vehicle group was injected with corresponding amount intraperitoneally every day for 6 weeks. Six weeks after streptozotocin injection, seven rats from each group were killed and brain, brain stem and cervical spinal cord were removed. The hippocampus, cortex, cerebellum, brain stem and spinal cord were dissected for the biochemical analysis (the level of malondialdehyde [MDA], total nitrite, reduced glutathione [GSH], and xanthine oxidase [XO] activity). STZ-induced diabetes resulted in significantly elevation of MDA, XO and nitrite levels in the hippocampus, cortex, cerebellum, brain stem and spinal cord of the rats (P < 0.05) while etomidate treatment provided significantly lower values (P < 0.05). This study demonstrated that etomidate have neuroprotective effect on the neuronal tissue against the diabetic oxidative damage. 相似文献
136.
Berna Saylan Cevik Ayhan Cevik Edide Tavli 《Indian pacing and electrophysiology journal》2010,10(2):96-98
Pseudo 2:1 AV block when sinus intervals are shorter than the ventricular refractory period has been reported with long QT syndrome (LQTS). We report the characteristics and treatment of a patient suffering from congenital LQTS with episodes of true 2:1 AV block. The pseudo 2:1 AV block relates to the extreme prolongation of ventricular refractoriness. Several histologic studies have documented abnormalities within the conduction system, including apoptosis. Because of the rare occurrence and poor prognosis of the LQTS with impaired AV conduction, international guidelines for diagnosis and treatment are needed. 相似文献
137.
138.
Güçlü BK Kara K Beyaz L Uyanik F Eren M Atasever A 《Biological trace element research》2008,125(2):160-169
This study was performed to determine the effects of copper proteinate on performance, blood chemistry, lipid peroxidation
status, and organs as well as copper deposition in the liver and eggs of laying hens. Seventy-two 30-week-old Bovans laying
hens were distributed into four groups with three replicates. Animals were fed basal diet containing at least 17% crude protein
and 2,800 kcal/kg metabolizable energy supplemented with either 0, 150, 300, or 450 mg/kg copper as copper proteinate. Supplementation
of 150 and 300 mg/kg copper increased egg production, whereas 450 mg/kg copper decreased (p < 0.001). Liver copper levels were elevated in 300 and 450 mg/kg copper-supplemented groups (p < 0.001). Egg copper contents increased in all treatment groups (p < 0.01). An increase in glucose (p < 0.001) and decreases in albumin (p < 0.01) and total cholesterol (p < 0.05) levels were determined with 300 and 450 mg/kg copper. Supplementation of 450 mg/kg copper increased alkaline phosphatase
and gamma glutamyl transpeptidase activities (p < 0.05), malondialdehyde, and high-density lipoprotein levels (p < 0.01) but decreased alanine aminotransferase and lactate dehydrogenase activities (p < 0.01). No gross and microscopic changes were observed in the liver and kidneys. These results indicated that 150 and 300 mg/kg
copper increased egg production without having marked adverse effects, but 450 mg/kg copper altered some blood chemistry variables
and reduced egg production in laying hens. 相似文献
139.
Incorporation of hazelnut shell and husk in MDF production 总被引:1,自引:0,他引:1
Hazelnut shell and husk (Coryllus arellana L.) is an abundant agricultural residue in Turkey and investigating the possibilities of utilizing husk and shell in panel production might help to overcome the raw material shortage that the panel industry is facing. The aim of this work was to investigate the possibilities of utilizing hazelnut shell and husk in medium density fiberboard (MDF) production. To produce general purpose fiberboards, fiber-husk and fiber-shell mixtures at various percentages were examined in this study. The results indicated that panels could be produced utilizing hazelnut husk up to 20% addition without falling below the properties required in the standards. Shell addition was restricted up to 10%, because higher addition levels diminished the elastic modulus and internal bond strength below the acceptable level. 相似文献
140.
Ayhan S Tugay C Ortak T Prayson R Parker M Siemionow M Papay FA 《Plastic and reconstructive surgery》2002,109(4):1333-1337
Bioabsorbable materials are frequently used in pediatric cranial surgery, but the effects of these materials on neural tissue are not known. The authors assessed the histologic alterations to dura mater and brain tissue associated with bioabsorbable plates. Fifteen Sprague-Dawley rats were given sham cranial surgery; an additional 30 underwent placement of 8 x 8-mm polylactic acid/poly-glycolic acid plates. The rats were assessed weekly for neurologic or behavioral changes suggesting neural damage. A portion of each group was killed at 3, 6, and 12 months for histologic analysis of cranium, dura mater, and brain tissue by standard hematoxylin and eosin stain. None of the animals showed any behavioral changes or neurologic deficits. The plates were gradually hydrolyzed over the study period, and all had disappeared by 12 months. The histologic examination showed fibrous encapsulation around the plates, accompanied by foreign body giant cell reaction and calcification. Focal gliosis, where evident, was mild and confined primarily to the superficial cortex of the brain beneath the plate. The infiltration of the dura mater and underlying brain parenchyma was negligible. In conclusion, the neurologic and histologic effect of bioabsorbable plates on neural tissue may be considered negligible in the early postoperative period. 相似文献