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111.
Three new species of ants (genus <Emphasis Type="Italic">Aphaenogaster</Emphasis>, Hymenoptera: Formicidae) from Turkey 总被引:1,自引:0,他引:1
Three new species of the ant genus Aphaenogaster (A. aktaci sp. n., A. maculifrons sp. n., A. radchenkoi sp. n.) are described from Turkey and their taxonomic positions are discussed. Aphaenogaster aktaci sp. n. belongs to the obsidiana group, A. maculifrons sp. n. to subterranea group and A. radchenkoi sp. n. to pallida group of the Attomyrma subgenus. Key characteristics for identification of the species and data on their ecology are given. 相似文献
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Facultative phototrophic bacterium Rhodobacter capsulatus DsbA-null mutants are proficient in photosynthesis but are defective in respiration especially in enriched growth medium at 35 degrees C. They also exhibit severe pleiotropic phenotypes extending from motility defects to osmofragility and oxidative stresses. In this work, using a combined proteomics and molecular genetics approach, we demonstrated that the respiratory defect of R. capsulatus DsbA-null mutants originates from the overproduction of the periplasmic protease DegP, which renders them temperature-sensitive for growth. The DsbA-null mutants reverted frequently to overcome this growth defect by decreasing, but not completely eliminating, their DegP activity. In agreement with these findings, we showed that overproduction of DegP abolishes the newly restored respiratory growth ability of the revertants in all growth media. Structural localizations of the reversion mutations in DegP revealed the regions and amino acids that are important for its protease-chaperone activity. Remarkably although R. capsulatus DsbA-null or DegP-null mutants were viable, DegP-null DsbA-null double mutants were lethal at all growth temperatures. This is unlike Escherichia coli, and it indicates that in the absence of DsbA some DegP activity is required for survival of R. capsulatus. Absence of a DegQ protease homologue in some bacteria together with major structural variations among the DegP homologues, including a critical disulfide bond-bearing region, correlates well with the differences seen between various species like R. capsulatus and E. coli. Our findings illustrate the occurrence of two related but distinct periplasmic protease families in bacterial species. 相似文献
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Serdar Turkarslan Arjun V Raman Anne W Thompson Christina E Arens Mark A Gillespie Frederick von Netzer Kristina L Hillesland Sergey Stolyar Adrian López García de Lomana David J Reiss Drew Gorman‐Lewis Grant M Zane Jeffrey A Ranish Judy D Wall David A Stahl Nitin S Baliga 《Molecular systems biology》2017,13(3)
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The effect of glutamine on radiation-induced organ damage 总被引:4,自引:0,他引:4
Erbil Y Oztezcan S Giriş M Barbaros U Olgaç V Bilge H Küçücük H Toker G 《Life sciences》2005,78(4):376-382
Radiation enteritis is a significant clinical problem in patients receiving ionizing radiation directed to the abdomen or pelvis. Although radiation is aimed to be directed against the malignant tissue, adjacent healthy tissues are also affected. The small intestine is the most sensitive organ to radiation. The present study was undertaken to investigate the possible protective effect of glutamine against radiation-induced intestinal, hepatic and pancreatic toxicity. Rats received 1 g/kg/day glutamine for seven days before irradiation and continued for three days after irradiation until sacrifice. Then intestinal, pancreatic and hepatic myeloperoxidase (MPO) activities, malondialdehyde (MDA) levels and caspase-3 activities of the sacrificed rats were measured. Irradiation significantly increased the intestinal and pancreatic MPO and caspase-3 activities and MDA levels in comparison to sham group. Glutamine treatment significantly decreased this elevation. Histopathological examination revealed that the intestinal mucosal structure was preserved and pancreatic inflammation decreased in the glutamine treated group. In irradiation group, NF-kappaB over expression was detected. There was no significant difference in histopathological and biochemical examinations of the liver between the groups. In conclusion, glutamine has beneficial effects on intestinal and pancreatic damage in abdominal irradiation through the inflammatory process and apoptosis. 相似文献
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Erkasap S Erkasap N Aral E Koken T Kahraman A Aydin Y Yilmaz S Ates E 《The Chinese journal of physiology》2005,48(1):1-6
The role of epidermal growth factor (EGF), a polypeptide containing 53 amino acids, on protection and repair of ethanol-induced gastric mucosal injury was investigated in rats. In addition, the effects of EGF on the gastric damage were evaluated histopathologically. We used 48 Spraque-Dawley rats which were divided into [corrected] three groups as control rats, ethanol treated rats and ethanol+EGF treated rats. The ethanol group was given a gastric gavage containing 1 ml of 80% ethanol (v/v) prepared in distilled water. EGF (100 microg/kg) was given by intragastric gavage 30 min before the administration of ethanol. We studied histopathological evaluation and the histochemical heterogeneity of mast cells and its degree of degranulation. Besides, gastric tissue malondialdehyde (MDA), protein sulfhydryl groups (SH), and protein carbonyl levels were measured. EGF treatment stabilized mast cells degranulation and had lower polymorphonuclear leukocytes (PMNL) infiltration, ulcer index, histamine, and MDA; protein carbonyl levels were also lower, compared to the non-treated animals. EGF exerts a protective effect on gastric mucosa to ethanol-induced gastric injury probably through antioxidant and mast cell stabilizing mechanism. 相似文献
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Mehmet Enes Coşkun Mehmet Kervancıoğlu Serdar Öztuzcu Fatma Yılmaz Coşkun Sercan Ergün Osman Başpınar 《Biomarkers》2016,21(1):56-61
Context: Dilated cardiomyopathy (DCM) is the most common cardiomyopathy in children. MicroRNAs (miRNA) are small RNAs which have regulatory functions in many biological processes.Objective: We aimed to determine miRNA expression levels in plasma of children with DCM.Materials and methods: Plasma expression levels of 379 miRNAs were compared between 23 DCM and 26 healthy children.Results: The expression levels of miR-618, miR-875-3p, miR-205, miR-194, miR-302a, miR-147, and miR-544 were found decreased. The expression levels of miR-518f and miR-454 were found increased in DCM patients.Discussion: miRNA level differences may provide the chance of using these miRNAs as new biomarkers. 相似文献