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161.
Dokmeci D Inan M Basaran UN Yalcin O Aydogdu N Turan FN Uz YH 《Cell biochemistry and function》2007,25(6):611-618
Testicular torsion is a urological emergency referred to as 'acute scrotum', because inappropriate treatment can lead to male subfertility and infertility. A possible cause of testicular damage is the ischaemia-reperfusion (I/R) injury attributed to oxygen free radicals. L-carnitine, a vitamin-like antioxidant, plays a pivotal role in the maturation of spermatozoa within the reproductive tract. The aim of the present paper was to determine the protective effect of L-carnitine on testicular I/R-induced injury. Thirty-two male rats were divided into 4 groups (n = 8). Testicular torsion was created by rotating the right testis 720 degrees in a clockwise direction. Group 1: sham-operated control; group 2: ischaemia; group 3: I/R; group 4: ischaemia-L-carnitine treatment-reperfusion group. L-carnitine (500 mg kg(-1), intraperitoneally) was administered before 30 min of detorsion in Group 4. After torsion (5 h) and detorsion (5 h), bilateral orchidectomy was performed. The malondialdehyde (MDA) level was evaluated in testes. Histopathologically, Johnsen's spermatogenesis criteria and mean seminiferous tubule diameter (MSTD) measurements were used. Testicular MDA levels were higher in the torsion group compared to the sham-control group (p < 0.05). Detorsion (reperfusion) caused a further increase in MDA levels (p < 0.05). Pretreatment with L-carnitine prevented a further increase in MDA levels (p < 0.05). Histologically, torsion caused some separation among germinal cells in the seminiferous tubules, which became much more prominent in the I/R group but was attenuated with L-carnitine pretreatment. In conclusion, L-carnitine pretreatment may have a protective effect in experimental testicular torsion-detorsion model in rats by its well-known antioxidant potential. 相似文献
162.
Barr J Sharma CS Sarkar S Wise K Dong L Periyakaruppan A Ramesh GT 《Molecular and cellular biochemistry》2007,304(1-2):93-99
Super CitriMax (HCA-SX) is a novel calcium/potassium salt of (−)-hydroxycitric acid extracted from the dried fruit rind of
the plant Garcinia cambogia, and commonly consumed as weight loss dietary supplement. In the present study, we investigated the effect of HCA-SX on inflammation,
oxidative stress and insulin resistance in developing obese Zucker rats, an animal model of type II diabetes associated with
inflammation and oxidative stress. Male Zucker rats (5-week old) were supplemented with vehicle (control) and HCA-SX in drinking
water for 7 weeks. Oxidative stress markers, including malondialdehyde (MDA), protein carbonyl (DNPH), and protein tyrosine
nitration (tyr-NO2) were measured in the liver and kidney tissues using biochemical and immunoblotting techniques. Compared to controls, the
levels of MDA, DNPH and tyr-NO2 were lower in the liver and kidney of HCA-SX-treated animals. Furthermore, the levels of C-reactive protein and interleukin-6,
markers of inflammation measured by ELISA, were lower in the plasma of HCA-SX-supplemented animals compared to controls, as
were levels of fasting plasma insulin, glucose, and triglycerides. Interestingly, insulin resistance did not develop in HCA-SX-supplemented
rats. Food-intake and body weight gain was also lower in rats supplemented with HCA-SX compared to their control counterparts.
These results suggest that HCA-SX supplementation in obese Zucker rats reduces food-intake, body weight gain, and also attenuates
the increases in inflammation, oxidative stress, and insulin resistance observed in untreated animals. Therefore, HCA-SX may
be used as an intervention to overcome obesity-related complications, including inflammation, oxidative stress, and insulin
resistance. 相似文献
163.
Four isoenzymes of carbonic anhydrase (CA) were purified from Elephas Irogontherii (steppe elephant) bone (approx 0.3-0.5 million years old) from different locations (outer peripheral, cytosolic, inner peripheral and integral) using Sepharose 4B-L-tyrosine sulphanilamide affinity chromatography and their kinetics properties were investigated and compared with known CA isoenzymes. The purification degree of CAs was monitored by SDS-PAGE. Purification fold for outer peripheral, inner peripheral, cytosolic and integral CA was 395.6, 652.8, 1091 and 429.3 and the molecular mass (as determined by gel filtration chromatography) was 37, 36, 35, and 39 kDa, respectively. The optimal temperature for isozymes was 10-20, 30, 30 and 60 degrees C and optimal pH- was between 7.5-11, 7.5-10, 7.5-10 and 7.5 respectively. K(m) values (at optimum pH and 20 degrees C) for p-nitrophenyl acetate as substrate were 4.83, 6.80, 4.525 and 3.86 mM and the Vmax values for the same substrate were 0.00097, 0.0149, 0.00249 and 0.00072 micromol/L*min, respectively. I50 values of isoenzymes for the inhibitors of CA - sulphanilamide, KSCN, acetazolamide and NaN3 were also determined. 相似文献
164.
Fire resistance of Douglas fir (Pseudotsuga menzieesi) treated with borates and natural extractives 总被引:1,自引:0,他引:1
The objective of this study was to determine fire resistance of Douglas fir (Pseudotsuga menzieesi (Mirb.) Franco) specimens treated with borate supplemented aqueous solutions of brutia pine bark powder, acorn powder, sumach leaf powder, and gall-nut powder. Boric acid (BA) and borax (BX) were used as borates which are the most commonly used fire retardants in wood preservation industry. Natural extractives (brutia pine bark powder, sumach leaf powder, acorn powder, and gall-nut powder) were also used which have toxic efficiency against insects and fungi due to their tannin contents. A commercial treatment compound Tanalith-CBC (copper-borate-chromate), which is an impregnation chemical, is used for comparison. The fire test method was performed in three stages: flame stage, without flame stage, and glowing stage. Results indicated that the lowest temperature for flame stage, without flame stage, and glowing stage were obtained for specimens treated with BA and BX mixture (7:3; weight:weight). The lowest mass loss was found for the specimens treated with a mixture of BA and BX. Natural extractives did not improve fire resistance of the samples. However, boric acid and borax had excellent fire retardant effectiveness over untreated and treated samples with natural extractives. 相似文献
165.
In Turkey, Leishmania infantum is responsible for human visceral leishmaniasis (VL), which is seen mainly in the Aegean, Mediterranean, and Central Anatolia Regions. This study aimed to determine asymptomatic infections in an endemic area of VL in Turkey using the western blot technique. A total of 82 persons including children and adults were chosen randomly in Denizli province which is one of the endemic sites for VL. Serum samples were collected and screened using indirect immunofluorescent test (IFAT), enzyme-linked immunosorbent assay (ELISA) and western blot (WB). One year later, 35 of the 82 persons were sampled and screened serologically for the second time. Seven out of 82 samples were found to be positive by western blot analysis with the presence of 14 and/or 18 kDa bands. Two of these seven sera were also positive by IFAT, but only one of these two was positive by ELISA. Only one person showing seropositivity with all three tests had clinical symptoms and was diagnosed as VL with the presence of amastigotes in bone marrow aspirate. Because six people, including the one found to be seropositive in all two tests, had no clinical symptoms, they were accepted as asymptomatic carriers. The ratio of asymptomatic infection was calculated as 7.41% (6/81) in the region. In the second sampling, the western blot revealed antibodies against the same antigens in all seven subjects. Our findings showed that the presence of antibodies against 14 and 18 kDa antigens are important for the diagnosis of symptomatic and asymptomatic infections. Western blot was found to be effective in the detection of asymptomatic persons in the epidemiological studies in endemic areas. 相似文献
166.
Gul M Ciragil P Bulbuloglu E Aral M Alkis S Ezberci F 《Acta microbiologica et immunologica Hungarica》2007,54(3):317-321
Comamonas testosteroni is an uncommon isolate in the clinical laboratory as a human pathogen. C. testosteroni most commonly emerges in abdominal pathologies especially in perforated appendicitis. In Turkey we report first time a case of bacteremia due to this organism, in a 22-year-old man with perforated acute appendicitis. The organism was shown to be susceptible to routine antibiotics so it was easily eliminated even after having caused a bacteremia. 相似文献
167.
The present work examined the effect of chronic oral administration of quercetin, a flavonoid antioxidant, on blood glucose, vascular function and oxidative stress in STZ-induced diabetic rats. Male Wistar-Kyoto (WKY) rats were randomized into euglycemic, untreated diabetic, vehicle (1% w/v methylcellulose)-treated diabetic, which served as control, or quercetin (10mgkg(-1) body weight)-treated diabetic groups and treated orally for 6 weeks. Quercetin treatment reduced blood glucose level in diabetic rats. Impaired relaxations to endothelium-dependent vasodilator acetylcholine (ACh) and enhanced vasoconstriction responses to alpha(1)-adrenoceptor agonist phenylephrine (PE) in diabetic rat aortic rings were restored to euglycemic levels by quercetin treatment. Pretreatment with N(omega)-nitro-l-arginine methyl ester (l-NAME, 10microM) or methylene blue (10microM) completely blocked but indomethacin (10microM) did not affect relaxations to ACh in aortic rings from vehicle- or quercetin-treated diabetic rats. PE-induced vasoconstriction with an essentially similar magnitude in vehicle- or quercetin-treated diabetic rat aortic rings pretreated with l-NAME (10microM) plus indomethacin (10microM). Quercetin treatment reduced plasma malonaldehyde (MDA) plus 4-hydroxyalkenals (4-HNE) content as well as increased superoxide dismutase activity and total antioxidant capacity in diabetic rats. From the present study, it can be concluded that quercetin administration to diabetic rats restores vascular function, probably through enhancement in the bioavailability of endothelium-derived nitric oxide coupled to reduced blood glucose level and oxidative stress. 相似文献
168.
Elevated homocysteine levels in patients with slow coronary flow: relationship with Helicobacter pylori infection 总被引:2,自引:0,他引:2
Evrengul H Tanriverdi H Kuru O Enli Y Yuksel D Kilic A Kaftan A Kirac S Kilic M 《Helicobacter》2007,12(4):298-305
BACKGROUND AND OBJECTIVE: Elevation of plasma homocysteine (Hcy) level has been implicated in the pathogenesis of slow coronary flow (SCF) as it can severely disturb vascular endothelial function. Helicobacter pylori chronically infect the human stomach and causes malabsorption of vitamin B(12) and folate in food, leading ultimately to an increase in circulating Hcy levels. METHODS: Forty-three patients with angiographically proven SCF (group I) were enrolled in this study; 43 cases with normal coronary flow pattern (group II) served as controls. Fasting plasma levels of Hcy, vitamin B(12), and folate were measured in all subjects. Presence of H. pylori infection was defined as positive 14 C urea breath test. Coronary flow patterns for each major epicardial coronary artery were determined with the Thrombolysis in Myocardial Infarction (TIMI) frame count method. RESULTS: Mean TIMI frame count was 46.3 +/- 8.7 in group I and 24.3 +/- 2.9 in Group II (p = .0001). Vitamin B(12) levels were similar, whereas folate levels were dramatically reduced in group I compared to group II (13.2 +/- 4.3 vs. 17.1 +/- 5.2, p = .0001). Plasma Hcy levels were significantly higher in group I compared to group II (13.4 +/- 5.6 vs. 7.9 +/- 2.5, p = .0001) as was the prevalence of H. pylori infection (90.7% in group I vs. 58.1% in group II, p = .001). Hcy levels were elevated (11.7 +/- 5.3 vs. 7.5 +/- 2.7, p = .0001) and folate levels were reduced (13.9 +/- 4.7 vs. 18.6 +/- 4.9, p = .0001) in patients with H. pylori infection, while vitamin B(12) levels were similar in patients with and without H. pylori infection. Correlation analysis revealed a significant negative correlation between plasma folate and Hcy levels and also between folate levels and mean TIMI frame counts (r = -.33, p = .002 vs. r = -.33, p = .003). Moreover, there was a significant positive correlation between plasma Hcy levels and mean TIMI frame counts (r = .66, p = .0001). In addition, the folate level was the only significant determinant of the variance of Hcy in multiple regression analysis (r = -.21, p = .03). CONCLUSION: Our data showed that plasma folate levels were decreased and plasma Hcy levels were increased in patients with SCF compared to controls. Also, the prevalence of H. pylori infection was increased in patients with SCF. These findings suggest that elevated levels of plasma Hcy, possibly caused by H. pylori infection, and/or a possible disturbance in its metabolism may play a role in the pathogenesis of SCF. 相似文献
169.
Ince IA Demir I Demirbag Z Nalcacioglu R 《Journal of microbiology and biotechnology》2007,17(4):632-637
A cytoplasmic polyhedrosis virus (CPV) was isolated from the larvae of Thaumetopoea pityocampa and shown to cause an infection of midgut cells. This viral infection revealed several important diagnostic symptoms, including discoloration of the posterior midgut, reduced feeding, and extended development time of the larvae. The virus infection is lethal to Thaumetopoea pityocampa, and with the increasing doses kills the larvae within 4-5 days post infection. Electron microscopy studies showed typical cytoplasmic polyhedral inclusion bodies that are icosahedral, and ranged from 2.4 to 5.3 microm in diameter. Electrophoretic analysis of the RNA genome showed that the virus has a genome composed of 10 equimolar RNA segments with the sizes of 3,907, 3,716, 3,628, 3,249, 2,726, 1,914, 1,815, 1,256, 1,058, and 899 bp, respectively. Based on morphology and nucleic acid analysis, this virus was named Thaumetopoea pityocampa cytoplasmic polyhedrosis virus (TpCPV), and belongs to the genus Cypovirus, family Reoviridae. 相似文献
170.