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61.
The antimicrobial activities of chloroform, acetone and two different concentrations of methanol extracts of Artemisia dracunculus L. were studied. These extracts were tested against nine bacteria and four yeasts strains by the disc diffusion method. The results indicated that the methanol extract of A. dracunculus is more effective against tested microorganisms than chloroform or acetone extracts. The chloroform and acetone extracts were inhibitory only towards Pseudomonas aeruginosa (ATCC 27853). While the methanol extract that was diluted with 10 ml distilled water showed inhibition zones against Shigella (RSHI), Listeria monocytogenes ATCC 7644, P. aeruginosa (ATCC 27853), the methanol extract that was diluted with 5 ml distilled water showed inhibition zones against two different strains of Escherichia coli (RSHI, ATCC 25922), Shigella (RSHI), L. monocytogenes (ATCC 7644), and P. aeruginosa ATCC 27853. The cells of microorganisms treated with plant extracts and normal microorganism cells were observed by scanning electron microscope. It was apparent that cells are damaged after treatment with A. dracunculus. 相似文献
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P. J. Weathers B. E. Wyslouzil K. K. Wobbe Y. J. Kim E. Yigit 《In vitro cellular & developmental biology. Plant》1999,35(4):286-289
Summary The efficient exchange of gases between roots and their environment is one of the biggest challenges in bioreactor design
for transformed root cultures. Gas-phase reactors can alleviate this problem as well as provide a new tool for studying the
biological response of roots and other differentiated tissues to changes in the gas phase composition. In our comparison of
liquid- and gas-phase reactors, roots grown in liquid (shake flasks or bubble column reactors) are shown to be under hypoxic
stress. Roots grown in a gas-phase reactor (nutrient mist), while not hypoxic, produced 50% less biomass. These results suggest
that the response of the tissues to gas phase composition are complex and need further study. 相似文献
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Bo An Vittorio Abbonante Sezin Yigit Alessandra Balduini David L. Kaplan Barbara Brodsky 《The Journal of biological chemistry》2014,289(8):4941-4951
Interaction of collagen with fibronectin is important for extracellular matrix assembly and regulation of cellular processes. A fibronectin-binding region in collagen was identified using unfolded fragments, but it is not clear if the native protein binds fibronectin with the same primary sequence. A recombinant bacterial collagen is utilized to characterize the sequence requirement for fibronectin binding. Chimeric collagens were generated by inserting the putative fibronectin-binding region from human collagen into the bacterial collagen sequence. Insertion of a sufficient length of human sequence conferred fibronectin affinity. The minimum sequence requirement was identified as a 6-triplet sequence near the unique collagenase cleavage site and was the same in both triple-helix and denatured states. Denaturation of the chimeric collagen increased its affinity for fibronectin, as seen for mammalian collagens. The fibronectin binding recombinant collagen did not contain hydroxyproline, indicating hydroxyproline is not essential for binding. However, its absence may account, in part, for the higher affinity of the native chimeric protein and the lower affinity of the denatured protein compared with type II collagen. Megakaryocytes cultured on chimeric collagen with fibronectin affinity showed improved adhesion and differentiation, suggesting a strategy for generating bioactive materials in biomedical applications. 相似文献
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Yun Li Barbara Pawlik Nursel Elcioglu Mona Aglan Gökhan Yigit Ferda Percin Gudrun Nürnberg Asim Cenani Boi-Dinh Chung Samira Ismail Ayca D. Aslanger Christian Netzer Pete Scambler Hanan Hamamy Raoul Hennekam Peter Nürnberg Joachim Herz Bernd Wollnik 《American journal of human genetics》2010,86(5):696-40630
67.
Modelling cytomegalovirus replication patterns in the human host: factors important for pathogenesis
Regoes RR Bowen EF Cope AV Gor D Hassan-Walker AF Prentice HG Johnson MA Sweny P Burroughs AK Griffiths PD Bonhoeffer S Emery VC 《Proceedings. Biological sciences / The Royal Society》2006,273(1596):1961-1967
Human cytomegalovirus can cause a diverse range of diseases in different immunocompromised hosts. The pathogenic mechanisms underlying these diseases have not been fully elucidated, though the maximal viral load during infection is strongly correlated with the disease. However, concentrating on single viral load measures during infection ignores valuable information contained during the entire replication history up to the onset of disease. We use a statistical model that allows all viral load data sampled during infection to be analysed, and have applied it to four immunocompromised groups exhibiting five distinct cytomegalovirus-related diseases. The results show that for all diseases, peaks in viral load contribute less to disease progression than phases of low virus load with equal amount of viral turnover. The model accurately predicted the time of disease onset for fever, gastrointestinal disease and pneumonitis but not for hepatitis and retinitis, implying that other factors may be involved in the pathology of these diseases. 相似文献
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Ciftci IH Cetinkaya Z Atambay M Kiyildi N Aycan OM Daldal N 《The Korean journal of parasitology》2006,44(3):259-264
House dust mites play an important role in the pathogenesis of allergic diseases. Many factors may influence mite growth. The presence of mites is related to mean temperature and humidity as well as altitude. The aim of this study was to analyze the mite fauna in 5 regions of western Anatolia, Turkey, that have similar climatic properties with low mean temperature and humidity, but differ in altitude. During the period October-November 2004, house dust was collected from 290 homes in 5 different cities. House dust mites were isolated in 67 (23.1%) of 290 samples. The family Pyroglyphidae (Astigmata) was present in all positive samples. This study suggests that the selected western Anatolian regions that share similar environmental conditions host similar dust mite populations. 相似文献
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Background
Diabetic peripheral neuropathy (DPN) is a microvascular complication of diabetes mellitus (DM) due to decreasing quality of life. In the present study, it is aimed to evaluate angiotensin-converting enzyme (ACE) Gene I/D polymorphism in Turkish population.Materials and methods
Two hundred and thirty-five DPN patients and two hundred and eighty-one controls were enrolled in this study. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) analyses for the ACE gene I/D polymorphism.Results
Baseline characteristics of the DPN patients according to ACE genotypes were similar, except for history of hypertension. The frequency of II genotype was significantly higher in patients with positive history of hypertension than the patients with negative history of hypertension (p = 0.013). DD genotype of I/D polymorphism was found to be a susceptibility factor for DPN in homozygous form (p = 0.032). According to allele frequencies, D allele of I/D polymorphism was found to be a susceptibility factor for DPN (p = 0.031).Conclusion
ACE gene I/D polymorphism may research in DM patients to determine genetic predisposition for DPN. It can be useful for taking early measures and avoiding DPN in a Turkish population. 相似文献70.
Miyase Cinar Ebru Yildirim A.Arzu Yigit Ilkay Yalcinkaya Ozkan Duru Uçler Kisa Nurgul Atmaca 《Biological trace element research》2014,158(2):186-196
This study investigated effects of dietary supplementation with vitamin C, vitamin E on performance, biochemical parameters, and oxidative stress induced by copper toxicity in broilers. A total of 240, 1-day-old, broilers were assigned to eight groups with three replicates of 10 chicks each. The groups were fed on the following diets: control (basal diet), vitamin C (250 mg/kg diet), vitamin E (250 mg/kg diet), vitamin C + vitamin E (250 mg/kg?+?250 mg/kg diet), and copper (300 mg/kg diet) alone or in combination with the corresponding vitamins. At the 6th week, the body weights of broilers were decreased in copper, copper + vitamin E, and copper + vitamin C + vitamin E groups compared to control. The feed conversion ratio was poor in copper group. Plasma aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activities, iron, copper concentrations, and erythrocyte malondialdehyde were increased; plasma vitamin A and C concentrations and erythrocyte superoxide dismutase were decreased in copper group compared to control. Glutathione peroxidase, vitamin C, and iron levels were increased; aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and copper levels were decreased in copper + vitamin C group, while superoxide dismutase, glutathione peroxidase, and vitamin E concentrations were increased; aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase were decreased in copper with vitamin E group compared to copper group. The vitamin C concentrations were increased; copper, uric acid, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and malondialdehyde were decreased in copper + vitamin C + vitamin E group compared to copper group. To conclude, copper caused oxidative stress in broilers. The combination of vitamin C and vitamin E addition might alleviate the harmful effects of copper as demonstrated by decreased lipid peroxidation and hepatic enzymes. 相似文献