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Chromium picolinate is used in the poultry diet because of its antistress effects in addition to the fact that the requirement for it is increased during stress. This study was conducted to determine if the negative effects of high ambient temperature (34°C) on egg production, egg quality, antioxidant status, and cholesterol and mineral content of egg yolk could be alleviated by combination of chromium picolinate and biotin (0.6/2.0; Diachrome, as formulated by Nutrition 21 Inc.), in laying Japanese quails (Coturnix coturnix japanica), Quails (n=240; 50 d old) were divided into 8 groups, 30 birds per group. The quails were fed either a basal diet or the basal diet supplemented with 2, 4, or 8 mg of Diachrome/kg diet. Birds were kept at 22°C and 53% relative humidity (RH). At 14 wk of age, the thermoneutral (TN) group remained in the same temperature as at the beginning of experiment, whereas the heat stress (HS) group was kept in an environment-controlled room (34°C and 41% RH) for 3 wk. Heat exposure decreased performance when the basal diet was fed (p=0.001). Diachrome supplementation at 4 and 8 mg/kg diet, increased feed intake (p=0.05), egg production (p=0.05), feed efficiency (p=0.01), egg weight (p=0.05), and Haugh unit (p=0.01) in quails reared under heat stress conditions. Heat exposure increased concentrations of serum malondialdehyde (MDA) (p=0.001), glucose, and cholesterol (p=0.01), which were elevated by supplemental Diachrome (p≤0.05). Egg yolk Cr, Zn, and Fe (p=0.01) concentrations increased linearly, whereas MDA and cholesterol concentrations decreased (p=0.05) as dietary Diachrome supplementation increased in HS groups. Similar effects of supplementation on serum levels of glucose and cholesterol (p=0.05) and egg yolk concentrations of cholesterol (p=0.05) and Cr (p=0.01) were observed in TN groups. No significant differences in other values were observed in the TN groups. Results of the present study suggest that supplementation with Diachrome protects the quail by reducing the negative effects of heat stress.  相似文献   
113.
Hazelnut oil (HO) is rich in monounsaturated fatty acids and antioxidants. We wanted to investigate the effect of HO on lipid levels and prooxidant-antioxidant status in rabbits fed a high-cholesterol (HC) diet. An HC diet caused significant increases in lipids and lipid peroxide levels in the plasma, liver, and aorta together with histopathological atherosclerotic changes in the aorta. Glutathione levels, glutathione peroxidase, and glutathione transferase activities decreased significantly, but superoxide dismutase activity and vitamin E and C levels remained unchanged in the livers of rabbits following HC diet. HO supplementation reduced plasma, liver, and aorta lipid peroxide levels and aorta cholesterol levels together with amelioration in atherosclerotic lesions in the aortas of rabbits fed an HC diet, without any decreasing effect on cholesterol levels in the plasma or liver. HO did not alter the antioxidant system in the liver in the HC group. Our findings indicate that HO reduced oxidative stress and cholesterol accumulation in the aortas of rabbits fed an HC diet.  相似文献   
114.
Kocaeli University Medical School was established in 1995. The first methicillin resistant Staphylococcus aureus isolate was detected two years later in a patient transferred from a different city. Six months after this, we detected a small MRSA outbreak in the intensive care unit involving four patients, two of whom had bacteremia, and a staff nasal carrier. All isolates, including the first, appeared to be a single outbreak strain, demonstrated by pulsed field gel electrophoresis profiles which different by at most two bands, identical randomly amplified polymorphic DNA profiles, and identical coagulase gene types by PCR. Antibiogram were identical except that one isolate was additionally resistant to cotrimoxazole. These results show that MRSA isolates can spread between hospitals with infected or colonized patients and can apparently persist in the hospital for six months without causing infection. Screening of asymptomatic patients on wards affected by MRSA or transferred from other hospitals may be helpful in controlling these infections.  相似文献   
115.
Coral G  Omer C  Unaldi MN 《Folia biologica》2002,50(1-2):49-52
In this study, the chromosomal DNAs were extracted from Aspergillus niger Z10 wild type strain and these DNAs were separated using the contour clamped homogeneous electric field gel electrophoresis (CHEF) system. This system is laboratory-made and is operated by a computer program. Total DNAs resolved into five distinct chromosomal bands. The size of the chromosomes was estimated as being between 3.3 Mb to 6.4 Mb.  相似文献   
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The effect of a high-cholesterol diet with or without taurine on lipids and oxidative stress in the plasma, liver and aorta of rabbits was investigated. The animals were maintained on a basal diet (control), a high-cholesterol diet (HC, 1% w/w), or a high- cholesterol diet supplemented with taurine (HCHT, 2.5% w/w) for two months. Taurine has an ameliorating effect on atherosclerosis together with a decreasing effect on the cholesterol and triglyceride levels in rabbits fed on an HC diet. The HCHT diet caused a significant decrease in the malondialdehyde (MDA) and diene conjugate (DC) levels in the plasma, liver and aorta of rabbits as compared to the HC group. This treatment did not alter the antioxidant system in the liver of rabbits in the HC group. Our findings indicate that taurine ameliorated oxidative stress and cholesterol accumulation in the aorta of rabbits fed on the HC diet and that this effect may be related to its antioxidative potential as well as its reducing effect on serum lipids.  相似文献   
118.
The prokaryotic communities of four salterns (Bingöl, Fadlum, Kemah, and Tuzlagözü) in Turkey were examined and compared using the cultivation and cultivation-independent methods [fluorescence in situ hybridization (FISH) and 454 pyrosequencing]. FISH analysis with universal probes revealed that feeding waters carried 1.6 × 102–1.7 × 103 cells mL?1, while crystallization ponds carried 3.8 × 106–2.0 × 107 cells mL?1 that were mostly haloarchaea, including square cells (except for Kemah). High-throughput 16S rRNA-based gene sequencing showed that the most frequent archaeal OTUs in Bingöl, Fadlum, Tuzlagözü, and Kemah samples were affiliated with Haloquadratum (76.8 %), Haloarcula (27.8 %), Halorubrum (49.6 %), and Halonotius (59.8 %), respectively. Bacteroidetes was the dominant bacterial phylum in Bingöl and Fadlum, representing 71.5 and 79.5 % of the bacterial OTUs (respectively), while the most abundant bacterial phylum found in the Kemah saltern was Proteobacteria (79.6 %). The majority of the bacterial OTUs recovered from Tuzlagözü belonged to the Cyanobacteria (35.7 %), Bacteroidetes (35.0 %), and Proteobacteria (25.5 %) phyla. Cultivation studies revealed that the archaeal isolates were closely related to the genera Halobacterium, Haloarcula, and Halorubrum. Bacterial isolates were confined to two phyla, Proteobacteria (Alphaproteobacteria and Gammaproteobacteria classes) and Bacteroidetes. Comparative analysis showed that members of the Euryarchaeota, Bacteroidetes, Proteobacteria, and Cyanobacteria phyla were major inhabitants of the solar salterns.  相似文献   
119.
Zinc (Zn) is a component of numerous enzymes that function in a wide range of biological process, including growth, development, immunity and intermediary metabolism. Zn may play a role in chronic states such as cardiovascular disease and diabetes mellitus. Zn acts as cofactor and for many enzymes and proteins and has antioxidant, antiinflammatory and antiapoptotic effects. Taking into consideration that lung is a possible target organ for diabetic complications, the aim of this study was to investigate the protective role of zinc on the glycoprotein content and antioxidant enzyme activities of streptozotocin (STZ) induced diabetic rat tissues. Female Swiss albino rats were divided into four groups. Group I, control; Group II, control + zinc sulfate; Group III, STZ-diabetic; Group IV, diabetic + zinc sulfate. Diabetes was induced by intraperitoneal injection of STZ (65 mg/kg body weight). Zinc sulfate was given daily by gavage at a dose of 100 mg/kg body weight every day for 60 days to groups II and IV. At the last day of the experiment, rats were sacrificed, lung tissues were taken. Also, glycoprotein components, tissue factor (TF) activity, protein carbonyl (PC), advanced oxidative protein products (AOPP), hydroxyproline, and enzyme activities in lung tissues were determined. Glycoprotein components, TF activity, lipid peroxidation, non enzymatic glycation, PC, AOPP, hydroxyl proline, lactate dehydrogenase, catalase, superoxide dismutase, myeloperoxidase, xanthine oxidase, adenosine deaminase and prolidase significantly increased in lung tissues of diabetic rats. Also, glutathione levels, paraoxonase, arylesterase, carbonic anhydrase, and Na+/K+- ATPase activities were decreased. Administration of zinc significantly reversed these effects. Thus, the study indicates that zinc possesses a significantly beneficial effect on the glycoprotein components and oxidant/antioxidant enzyme activities.  相似文献   
120.
Among the thermophilic Bacillaceae family members, α-amylase production of 15 bacilli from genus Anoxybacillus was investigated, some of which are biotechnologically important. These Anoxybacillus α-amylase genes displayed?≥?91.0% sequence similarities to Anoxybacillus enzymes (ASKA, ADTA and GSX-BL), but relatively lower similarities to Geobacillus (≤?69.4% to GTA, Gt-amyII), and Bacillus aquimaris (≤?61.3% to BaqA) amylases, all formerly proposed only in a Glycoside Hydrolase 13 (GH13) subfamily. The phylogenetic analyses of 63 bacilli-originated protein sequences among 93 α-amylases revealed the overall relationships within Bacillaceae amylolytic enzymes. All bacilli α-amylases formed 5 clades different from 15 predefined GH13 subfamilies. Their phylogenetic findings, taxonomic relationships, temperature requirements, and comparisonal structural analyses (including their CSR-I-VII regions, 12 sugar- and 4 calcium-binding sites, presence or absence of the complete catalytic machinery, and their currently unassigned status in a valid GH13 subfamiliy) revealed that these five GH13 α-amylase clades related to familly share some common characteristics, but also display differentiative features from each other and the preclassified ones. Based on these findings, we proposed to divide Bacillaceae related GH13 subfamilies into 5 individual groups: the novel a2 subfamily clustered around α-amylase B2M1-A (Anoxybacillus sp.), the a1, a3 and a4 subfamilies (including the representatives E184aa-A (Anoxybacillus sp.), ATA (Anoxybacillus tepidamans), and BaqA,) all of which were composed from the division of the previously grouped single subfamily around α-amylase BaqA, and the undefinite subfamily formerly defined as xy including Bacillus megaterium NL3.  相似文献   
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