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161.
Perry AC Rosenblatt ES Kempner L Feldman BB Paolercio MA Van Bemden AL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2002,16(2):219-226
This study was performed to determine the effects of an exercise physiology program on physical fitness, body satisfaction, and knowledge. A total of 161 students (mean age = 16.5 +/- 0.89 years) of the Coral Gables Senior High School served as the experimental group volunteers, whereas 33 students enrolled in a standard biology course served as the control group (mean age = 15.61 +/- 0.84 years). The experimental group received exercise physiology theory coupled with active aerobic and resistance exercise. Age (p = 0.0001) and lean body mass (p = 0.023) were the only physical characteristics significantly greater in the experimental group at pretesting. An analysis of covariance controlling for pretest values showed better results in the experimental compared with the control group for sit and reach (p = 0.008), step test, recovery heart rate (p = 0.0002), overhead press (p = 0.002), bench press (p = 0.017), leg press (p = 0.012), sit-ups (p = 0.001), body satisfaction (p = 0.0009), and physiology knowledge (p = 0.0001) at posttesting. Findings indicated that a biology curriculum integrated with exercise physiology theory and exercise activities may result in significant improvements in physical fitness, body size satisfaction, and physiology knowledge in high school adolescents. 相似文献
162.
Margarita Martinez-Medina Plínio Naves Jorge Blanco Xavier Aldeguer Jesus E Blanco Miguel Blanco Carmen Ponte Francisco Soriano Arlette Darfeuille-Michaud L Jesus Garcia-Gil 《BMC microbiology》2009,9(1):202-16
Background
Crohn's disease (CD) is a high morbidity chronic inflammatory disorder of unknown aetiology. Adherent-invasive Escherichia coli (AIEC) has been recently implicated in the origin and perpetuation of CD. Because bacterial biofilms in the gut mucosa are suspected to play a role in CD and biofilm formation is a feature of certain pathogenic E. coli strains, we compared the biofilm formation capacity of 27 AIEC and 38 non-AIEC strains isolated from the intestinal mucosa. Biofilm formation capacity was then contrasted with the AIEC phenotype, the serotype, the phylotype, and the presence of virulence genes. 相似文献163.
E Teodori D Ettori A Garnier-Suillerot F Gualtieri D Manetti M N Romanelli S Scapecchi 《Bioorganic & medicinal chemistry》1999,7(9):1873-1880
The design and synthesis of two photoactivable biotin-labeled analogues of verapamil (6 and 7) is reported. Preliminary evaluation of the biological profile of 6 (EDP 137) and 7 (EDP 141) shows that they have comparable affinities to that of verapamil for P-170, the protein responsible for multidrug resistance (MDR). Since both appear to bind irreversibly to the protein and the presence of biotin in their structure makes them easily detectable by avidin, they promise to be of great help in studying the protein and its mechanism of action. 相似文献
164.
Dorothea Blomeyer Arlette F. Buchmann Jesus Lascorz Ulrich S. Zimmermann Günter Esser Sylvane Desrivieres Martin H. Schmidt Tobias Banaschewski Gunter Schumann Manfred Laucht 《PloS one》2013,8(3)
Background
Clock genes govern circadian rhythms and shape the effect of alcohol use on the physiological system. Exposure to severe negative life events is related to both heavy drinking and disturbed circadian rhythmicity. The aim of this study was 1) to extend previous findings suggesting an association of a haplotype tagging single nucleotide polymorphism of PER2 gene with drinking patterns, and 2) to examine a possible role for an interaction of this gene with life stress in hazardous drinking.Methods
Data were collected as part of an epidemiological cohort study on the outcome of early risk factors followed since birth. At age 19 years, 268 young adults (126 males, 142 females) were genotyped for PER2 rs56013859 and were administered a 45-day alcohol timeline follow-back interview and the Alcohol Use Disorders Identification Test (AUDIT). Life stress was assessed as the number of severe negative life events during the past four years reported in a questionnaire and validated by interview.Results
Individuals with the minor G allele of rs56013859 were found to be less engaged in alcohol use, drinking at only 72% of the days compared to homozygotes for the major A allele. Moreover, among regular drinkers, a gene x environment interaction emerged (p = .020). While no effects of genotype appeared under conditions of low stress, carriers of the G allele exhibited less hazardous drinking than those homozygous for the A allele when exposed to high stress.Conclusions
These findings may suggest a role of the circadian rhythm gene PER2 in both the drinking patterns of young adults and in moderating the impact of severe life stress on hazardous drinking in experienced alcohol users. However, in light of the likely burden of multiple tests, the nature of the measures used and the nominal evidence of interaction, replication is needed before drawing firm conclusions. 相似文献165.
Poirel N Simon G Cassotti M Leroux G Perchey G Lanoë C Lubin A Turbelin MR Rossi S Pineau A Houdé O 《PloS one》2011,6(6):e20879
Background
A real-world visual scene consists of local elements (e.g. trees) that are arranged coherently into a global configuration (e.g. a forest). Children show psychological evolution from a preference for local visual information to an adult-like preference for global visual information, with the transition in visual preference occurring around 6 years of age. The brain regions involved in this shift in visual preference have not been described.Methods and Results
We used voxel-based morphometry (VBM) to study children during this developmental window to investigate changes in gray matter that underlie the shift from a bias for local to global visual information. Six-year-old children were assigned to groups according to their judgment on a global/local task. The first group included children who still presented with local visual processing biases, and the second group included children who showed global visual processing biases. VBM results indicated that compared to children with local visual processing biases, children with global visual processing biases had a loss of gray matter in the right occipital and parietal visuospatial areas.Conclusions
These anatomical findings are in agreement with previous findings in children with neurodevelopmental disorders and represent the first structural identification of brain regions that allow healthy children to develop a global perception of the visual world. 相似文献166.
Dandelot S Matheron R Le Petit J Verlaque R Cazaubon A 《Comptes rendus biologies》2005,328(10-11):991-999
In France, two amphibious hydrophytes of alien Ludwigia (Onagraceae) have for about the past twenty years been causing serious ecological and economic problems: L. peploides (Kunth) Raven et L. grandiflora (Michaux) Greuter & Burdet. This bacteriological and physicochemical study, focused on three different Mediterranean aquatic ecosystems, reveals, for the first time, a direct negative impact of these American invaders. During summer, while plant growth is intensive, and the appearance in the water column of anoxic conditions and production of toxic compounds may be observed, notably in L. grandiflora stands. The toxicity is linked to a proliferation of sulphate-reducing bacteria producing sulphides that are very harmful for aquatic organisms. 相似文献
167.
Although young children can accurately determine that two rows contain the same number of coins when they are placed in a one-to-one correspondence, children younger than 7 years of age erroneously think that the longer row contains more coins when the coins in one of the rows are spread apart. To demonstrate that prefrontal inhibitory control is necessary to succeed at this task (Piaget's conservation-of-number task), we studied the relationship between the percentage of BOLD signal changes in the brain areas activated in this developmental task and behavioral performance on a Stroop task and a Backward Digit Span task. The level of activation in the right insula/inferior frontal gyrus was selectively related to inhibitory control efficiency (i.e., the Stroop task), whereas the activation in the left intraparietal sulcus (IPS) was selectively related to the ability to manipulate numerical information in working memory (i.e., the Backward Digit Span task). Taken together, the results indicate that to acquire number conservation, children's brains must not only activate the reversibility of cognitive operations (supported by the IPS) but also inhibit a misleading length-equal-number strategy (supported by the right insula/inferior frontal gyrus). 相似文献
168.
169.
Background
Associations have been made between obesity and reduced intestinal numbers of members of the phylum Bacteroidetes, but there is no direct evidence of the role these bacteria play in obesity. Herein, the effects of Bacteroides uniformis CECT 7771 on obesity-related metabolic and immune alterations have been evaluated.Methods and Findings
Adult (6–8 week) male wild-type C57BL-6 mice were fed a standard diet or a high-fat-diet HFD to induce obesity, supplemented or not with B. uniformis CECT 7771 for seven weeks. Animal weight was monitored and histologic, biochemical, immunocompetent cell functions, and features of the faecal microbiota were analysed after intervention. The oral administration of B. uniformis CECT 7771 reduced body weight gain, liver steatosis and liver cholesterol and triglyceride concentrations and increased small adipocyte numbers in HFD-fed mice. The strain also reduced serum cholesterol, triglyceride, glucose, insulin and leptin levels, and improved oral tolerance to glucose in HFD fed mice. The bacterial strain also reduced dietary fat absorption, as indicated by the reduced number of fat micelles detected in enterocytes. Moreover, B. uniformis CECT 7771 improved immune defence mechanisms, impaired in obesity. HFD-induced obesity led to a decrease in TNF-α production by peritoneal macrophages stimulated with LPS, conversely, the administration of B. uniformis CECT 7771 increased TNF-α production and phagocytosis. Administering this strain also increased TNF-α production by dendritic cells (DCs) in response to LPS stimulation, which was significantly reduced by HFD. B. uniformis CECT 7771 also restored the capacity of DCs to induce a T-cell proliferation response, which was impaired in obese mice. HFD induced marked changes in gut microbiota composition, which were partially restored by the intervention.Conclusions
Altogether, the findings indicate that administration of B. uniformis CECT 7771 ameliorates HFD-induced metabolic and immune dysfunction associated with intestinal dysbiosis in obese mice. 相似文献170.
Adherent-invasive Escherichia coli isolated from Crohn's disease patients induce granulomas in vitro
Meconi S Vercellone A Levillain F Payré B Al Saati T Capilla F Desreumaux P Darfeuille-Michaud A Altare F 《Cellular microbiology》2007,9(5):1252-1261
Adherent-invasive Escherichia coli (AIEC) have been shown to be highly associated with ileal Crohn's disease (CD). AIEC survive within infected macrophages, residing within the phagolysosomal compartment where they take advantage of the low pH to replicate extensively. We investigated whether, like the tuberculous bacillus which also persists within macrophages, AIEC LF82 induces the formation of granulomas, which are a common histopathological feature of CD. For this purpose, we have taken advantage of an in vitro model of human granulomas that we recently developed, based on blood-derived mononuclear cells. We demonstrated that AIEC LF82 induces aggregation of infected macrophages, fusion of some of them to form multinucleated giant cells and subsequent recruitment of lymphocytes. Light microscopy and scanning electron microscopy analysis of the cell aggregates confirmed their granuloma features. This was further confirmed by histological analysis of granuloma sections. Noteworthy, this phenomenon can be reproduced by soluble protein extracts of AIEC LF82 coated onto beads. Although the cell aggregates not completely mimic natural CD-associated granulomas, they are very similar to early stages of epithelioid granulomas. 相似文献