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41.
Pálenícek T Hlinák Z Bubeníková-Valesová V Votava M Horácek J 《Neuro endocrinology letters》2007,28(6):781-788
3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is a widely abused drug that impairs behavioral, emotional and cognitive functions in humans and animals. The aim of this study was to evaluate MDMA effects on the spontaneous behavioral repertoire of rats with a focus on the gender differences. MDMA was given subcutaneously in a single dose of 2.5, 5 and 10 mg/kg and the spontaneous behavior of male and female rats was studied using the open field test. Behavioral patterns (locomotion, rearing, floor-sniffing, air-sniffing, grooming, immobility and stereotypy) were registered in two sessions - 30 and 60 min following MDMA administration; each session lasting 5 min. We found that MDMA totally disrupted the structure and timing of spontaneous behavioral patterns in both genders; no evident differences were measured between either of the sessions. MDMA irrespective of the dosage produced hyperlocomotion, excessive floor-sniffing and almost absolute suppression of grooming and immobility. A biphasic effect of MDMA was found in rearing. Gender differences were present namely in rearing and sniffing stereotypy. This study also confirms that behavioral experiments should focus on more behavioral elements than only on e.g. locomotion and that the observer-based approach still gives the most reliable results. 相似文献
42.
Gestodene acidic treatment afforded a single rearrangement product, namely 13-beta-ethyl-18,19-dinorpregna-4,14,16-trien-3,20-dione 3, which was originated through HCl-catalyzed Rupe rearrangement. Drospirenone acidic treatment yielded two epimeric lactones by addition of HCl to the 6beta,7beta-cyclopropane ring, namely 7beta-(chloromethyl)-15beta,16beta-methylene-3-oxo-17beta-pregn-4-ene-21,17-carbolactone 4 and 7beta-(chloromethyl)-15beta,16beta-methylene-3-oxo-17alpha-pregn-4-ene-21,17-carbolactone 5. The structure of the compounds was assessed by spectroscopic and crystallographic methods. 相似文献
43.
Gabriella Juhasz Xenia Gonda Gabor Hullam Nora Eszlari David Kovacs Judit Lazary Dorottya Pap Peter Petschner Rebecca Elliott John Francis William Deakin Ian Muir Anderson Peter Antal Klaus-Peter Lesch Gyorgy Bagdy 《PloS one》2015,10(3)
Background
Although 5-HTTLPR has been shown to influence the risk of life stress-induced depression in the majority of studies, others have produced contradictory results, possibly due to weak effects and/or sample heterogeneity.Methods
In the present study we investigated how age, type and intensity of life-stressors modulate the effect of 5-HTTLPR on depression and anxiety in a European population cohort of over 2300 subjects. Recent negative life events (RLE), childhood adversity (CHA), lifetime depression, Brief Symptoms Inventory (BSI) depression and anxiety scores were determined in each subject. Besides traditional statistical analysis we calculated Bayesian effect strength and relevance of 5-HTTLPR genotypes in specified models.Results
The short (s) low expressing allele showed association with increased risk of depression related phenotypes, but all nominally significant effects would turn to non-significant after correction for multiple testing in the traditional analysis. Bayesian effect strength and relevance analysis, however, confirmed the role of 5-HTTLPR. Regarding current (BSI) and lifetime depression 5-HTTLPR-by-RLE interactions were confirmed. Main effect, with other words direct association, was supported with BSI anxiety. With more frequent RLE the prevalence or symptoms of depression increased in ss carriers. Although CHA failed to show an interaction with 5-HTTLPR, in young subjects CHA sensitized towards the depression promoting effect of even mild RLE. Furthermore, the direct association of anxiety with the s allele was driven by young (≤30) individuals.Limitations
Our study is cross-sectional and applies self-report questionnaires.Conclusions
Albeit 5-HTTLPR has only weak/moderate effects, the s allele is directly associated with anxiety and modulates development of depression in homogeneous subgroups. 相似文献44.
Gabriella Eliason Samy M Abdel-Halim Karin Piehl-Aulin Fawzi Kadi 《Respiratory research》2010,11(1):97
Background
It is hypothesized that decreased capillarization of limb skeletal muscle is implicated in the decreased exercise tolerance in COPD patients. We have recently demonstrated decreased number of capillaries per muscle fibre (CAF) but no changes in CAF in relation to fibre area (CAFA), which is based on the diffusion distance between the capillary and muscle fibre. The aim of the current study is to investigate the muscle-to-capillary interface which is an important factor involved in oxygen supply to the muscle that has previously been suggested to be a more sensitive marker for changes in the capillary bed compared to CAF and CAFA.Methods
23 COPD patients and 12 age-matched healthy subjects participated in the study. Muscle-to-capillary interface was assessed in muscle biopsies from the tibialis anterior muscle using the following parameters:1) The capillary-to-fibre ratio (C:Fi) which is defined as the sum of the fractional contributions of all capillary contacts around the fibre2) The ratio between C:Fi and the fibre perimeter (CFPE-index)3) The ratio between length of capillary and fibre perimeter (LC/PF) which is also referred to as the index of tortuosity.Exercise capacity was determined using the 6-min walking test.Results
A positive correlation was found between CFPE-index and ascending disease severity with CFPE-index for type I fibres being significantly lower in patients with moderate and severe COPD. Furthermore, a positive correlation was observed between exercise capacity and CFPE-index for both type I and type IIa fibres.Conclusion
It can be concluded that the muscle-to-capillary interface is disturbed in the tibialis anterior muscle in patients with COPD and that interface is strongly correlated to increased disease severity and to decreased exercise capacity in this patient group. 相似文献45.
Zuber S Carruthers F Keel C Mattart A Blumer C Pessi G Gigot-Bonnefoy C Schnider-Keel U Heeb S Reimmann C Haas D 《Molecular plant-microbe interactions : MPMI》2003,16(7):634-644
In the root-colonizing biocontrol strain CHA0 of Pseudomonas fluorescens, cell density-dependent synthesis of extracellular, plant-beneficial secondary metabolites and enzymes is positively regulated by the GacS/GacA two-component system. Mutational analysis of the GacS sensor kinase using improved single-copy vectors showed that inactivation of each of the three conserved phosphate acceptor sites caused an exoproduct null phenotype (GacS-), whereas deletion of the periplasmic loop domain had no significant effect on the expression of exoproduct genes. Strain CHA0 is known to synthesize a solvent-extractable extracellular signal that advances and enhances the expression of exoproduct genes during the transition from exponential to stationary growth phase when maximal exoproduct formation occurs. Mutational inactivation of either GacS or its cognate response regulator GacA abolished the strain's response to added signal. Deletion of the linker domain of the GacS sensor kinase caused signal-independent, strongly elevated expression of exoproduct genes at low cell densities. In contrast to the wild-type strain CHA0, the gacS linker mutant and a gacS null mutant were unable to protect tomato plants from crown and root rot caused by Fusarium oxysporum f. sp. radicis-lycopersici in a soil-less microcosm, indicating that, at least in this plant-pathogen system, there is no advantage in using a signal-independent biocontrol strain. 相似文献
46.
Coccetti P Zinzalla V Tedeschi G Russo GL Fantinato S Marin O Pinna LA Vanoni M Alberghina L 《Biochemical and biophysical research communications》2006,346(3):786-793
We have previously identified Ser201 of Sic1, a yeast cyclin-dependent kinase inhibitor, as an in vitro target of protein kinase CK2. Here we present new evidence, by using specific anti-P-Ser201 antibodies and 2-D gel electrophoresis coupled to MALDI mass spectrometry analysis, that Sic1 is phosphorylated in vivo on Ser201 shortly after its de novo synthesis, during late anaphase in glucose-grown cells. This phosphorylation is also detected in Sic1 immunopurified from G1 cells. In agreement with these data we also show that the catalytic alpha' subunit of CK2, whose function is required for cell cycle progression, is detected in Sic1 immunopurified complexes, and that phosphorylation on Ser201 is reduced after CK2 inactivation at the non-permissive temperature in a cka1delta cka2(ts) yeast strain. These data strongly support the notion that CK2 phosphorylates Sic1 in vivo. 相似文献
47.
Two wastewater natural reclamation systems (WWNRS) have been compared regarding their efficiencies on faecal bacteria removal and the persistence of enteric pathogens. These WWNRS are constituted of a combination of anaerobic treatment, small sub-surface flow constructed wetland refilled of volcanic ashes and a final pond as water reservoir. Faecal coliforms, enterococci, Escherichia coli, Clostridium perfringens, somatic coliphages, Salmonella sp., Campylobacter sp., Cryptosporidium sp., Giardia sp. and helminth eggs were analyzed in constructed wetlands inlet and outlet and storage pond effluent. Low numbers of protozoan positive samples (4.54% in Albergue de Bolico for both protozoa, and 19.05% in Carrizal Alto for Giardia sp.) and absence of helminth eggs were found. Both systems demonstrated efficient reduction of faecal contamination indicators in the wastewaters (removal rates values of 2 log10). The natural systems for wastewater treatment used to be efficient in Salmonella abatement, this fact was confirmed in the reported systems, since enterobacteriaceae were found in only one of the effluents. Campylobacter species associated with the access of animals to storage ponds were detected in the reclaimed water. 相似文献
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HOTAIR role in melanoma progression and its identification in the blood of patients with advanced disease 下载免费PDF全文