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21.
Manuel Pulido-Martos Juan Antonio Jiménez-Moral Esther Lopez-Zafra Jonatan R. Ruiz 《Child indicators research》2014,7(2):267-278
The aim of this study was to analyze the psychometric properties of a Spanish version of the Children’s Hope Scale (CHS), developed by Snyder et al. The sample included 388 adolescents between 12 and 18 years of age. The results of a confirmatory factor analysis validated the original theoretical structure with two factors, agency and pathways, with a cross-loading of one of the items (CFI?=0?.98; RMSEA?=0?.07; SRMR?=0?.03; CAIC?=??29.52). The instrument showed adequate internal consistency, with a Cronbach’s alpha of 0.76. Regarding convergent validity, significant correlations were found between the CHS and overall satisfaction with life, subjective happiness, dispositional optimism and positive affect. The Spanish version of the CHS therefore demonstrates adequate psychometric properties and can be used, along with other instruments, in educational contexts. 相似文献
22.
Epsilon toxin (Etx) from Clostridium perfringens is the third most potent toxin after the botulinum and tetanus toxins. Etx is the main agent of enterotoxemia in ruminants and is produced by Clostridium perfringens toxinotypes B and D, causing great economic losses. Etx selectively binds to target cells, oligomerizes and inserts into the plasma membrane, and forms pores. A series of mutants have been previously generated to understand the cellular and molecular mechanisms of the toxin and to obtain valid molecular tools for effective vaccination protocols. Here, two new non-toxic Etx mutants were generated by selective deletions in the binding (Etx-ΔS188-F196) or insertion (Etx-ΔV108-F135) domains of the toxin. As expected, our results showed that Etx-ΔS188-F196 did not exhibit the usual Etx binding pattern but surprisingly recognized specifically an O-glycoprotein present in the proximal tubules of the kidneys in a wide range of animals, including ruminants. Although diminished, Etx-ΔV108-F135 maintained the capacity for binding and even oligomerization, indicating that the mutation particularly affected the pore-forming ability of the toxin. 相似文献
23.
Dimitris Vlachopoulos Alan R. Barker Esther Ubago-Guisado Francisco B. Ortega Peter Krustrup Brad Metcalf Jose Castro Pinero Jonatan R. Ruiz Karen M. Knapp Craig A. Williams Luis A. Moreno Luis Gracia-Marco 《Journal of Science and Medicine in Sport》2018,21(4):404-409
Objectives
Research investigating the longitudinal effects of the most popular sports on bone development in adolescent males is scarce. The aim is to investigate the effect of 12-month participation in osteogenic and non-osteogenic sports on bone development.Design
A 12-month study was conducted in adolescent males involved in football, swimming and cycling and compared with an active control group.Methods
116 adolescent males (13.1 ± 0.1 years at baseline): 37 footballers, 37 swimmers, 28 cyclists and 14 active controls were followed for 12 months. Bone mineral content (BMC) was measured by dual-energy X-ray absorptiometry, and bone stiffness was measured by quantitative ultrasound. Bone outcomes at 12 months were adjusted for baseline bone status, age, height, lean mass and moderate to vigorous physical activity.Results
Footballers had higher improvement in adjusted BMC at the total body, total hip, shaft, Ward’s triangle, legs and bone stiffness compared to cyclists (6.3–8.0%). Footballers had significantly higher adjusted BMC at total body, shaft and legs compared to swimmers (5.4–5.6%). There was no significant difference between swimmers and cyclists for any bone outcomes. Swimming and cycling participation resulted in non-significant lower bone development at most sites of the skeleton compared to controls (?4.3 to ?0.6%).Conclusions
Football participation induces significantly greater improvements in BMC and bone stiffness over 12 months compared to cycling and swimming.Clinical trial registration
ISRCTN17982776. 相似文献24.
Félix Gómez-Gallego Jonatan R. Ruiz Amaya Buxens Marta Artieda David Arteta Catalina Santiago Gabriel Rodríguez-Romo José I. Lao Alejandro Lucia 《European journal of applied physiology》2009,107(5):565-569
The NOS3 gene is a candidate to explain individual variations in health and exercise related phenotypes. We compared genotypic and
allelic frequencies of the NOS3 −786 T/C polymorphism (rs2070744) in three groups of men of the same Caucasian (Spanish) descent: (i) elite endurance athletes
(cyclists, runners; N = 100); (ii) elite power athletes (jumpers, throwers, sprinters; N = 53) and (iii) non-athletic controls (N = 100). The frequency of the TT genotype was significantly higher in power athletes (57%) than in the endurance (33%, P = 0.017) or control group (34%, P = 0.026). The frequency of the T allele was also higher in power sportsmen (71%) than in their endurance (55%, P = 0.003) and control referents (56%, P = 0.015). No differences were observed between control and endurance groups. In summary, the −786 T/C polymorphism of the
NOS3 gene seems to be associated with elite performance in power-oriented athletic events (throwing, jumping, sprinting), with
the T allele exerting a beneficial effect. The mechanism by which this allele variant might benefit power performance remains
to be elucidated. 相似文献
25.
26.
Antibodies have the potential to be therapeutic reagents for malaria. Here we describe the production of a novel phage antibody display library against the C-terminal 19kDa region of the Plasmodium yoelii YM merozoite surface protein-1 (MSP1(19)). In vivo studies against homologous lethal malaria challenge show an anti-parasite effect in a dose dependent manner, and analysis by plasmon resonance indicates binding to the antigen is comparable to the binding of a protective monoclonal antibody. The data support the lack of a need for any antibody Fc-related function and hold great significance for the development of a therapeutic reagent for malaria. 相似文献
27.
Haugland HK Vukovic V Pintilie M Fyles AW Milosevic M Hill RP Hedley DW 《International journal of radiation oncology, biology, physics》2002,53(4):854-861
PURPOSE: To investigate the relations between hypoxia-inducible factor-1 (HIF-1), tumor oxygenation, and clinical correlates in patients with locally advanced carcinoma of the uterine cervix. METHODS AND MATERIALS: Biopsies from 42 patients with invasive cervical carcinoma and previous polarographic O2 measurements were assessed for the expression of HIF-1alpha using digitized microscopic imaging and analysis. RESULTS: The HIF-1alpha expression levels ranged from <0.1% to 10.7% of the total tumor area; the positive staining was localized exclusively to the nuclei. Three distinct arrangement patterns of HIF-1alpha-positive cells in relation to blood vessels were identified using spatial image mapping: (1) most HIF-1alpha-positive cells were located within the typical oxygen diffusion distance in tissue (< or =150 microm to the nearest blood vessel); (2) most HIF-1alpha-positive cells were located in the vicinity (< or =60 microm) of the blood vessels; and (3) no apparent spatial relationship was found between HIF-1alpha-positive cells and blood vessels. A statistically significant association was found between HIF-1alpha expression and tumor oxygenation (Spearman correlation coefficient = 0.4, p <0.01), as determined with the Eppendorf pO2 histograph. No correlation was found between the level of HIF-1alpha expression and patient outcome, using disease-free survival as the end point. CONCLUSION: Our results suggest that HIF-1alpha expression may represent a useful biologic marker for hypoxia in uterine cervical cancer. 相似文献
28.
Health-related fitness assessment in childhood and adolescence: a European approach based on the AVENA, EYHS and HELENA studies 总被引:1,自引:0,他引:1
Jonatan R. Ruiz Francisco B. Ortega Angel Gutierrez Dirk Meusel Michael Sjöström Manuel J. Castillo 《Zeitschrift fur Gesundheitswissenschaften》2006,14(5):269-277
Results from cross-sectional and longitudinal studies such as Alimentación y Valoración del Estado Nutricional en Adolescentes: Food and Assessment of the Nutritional Status of Spanish Adolescents (AVENA) and the European Youth Heart Study (EYHS) respectively, highlight physical fitness as a key health marker in childhood and adolescence. Moderate and vigourous levels of physical activity stimulate functional adaptation of all tissues and organs in the body (i.e. improve fitness), thereby also making them less vulnerable to lifestyle-related degenerative and chronic diseases. To identify children and adolescents at risk for these major public health diseases and to be able to evaluate the effects of alternative intervention strategies in European countries and internationally, comparable testing methodology across Europe has to be developed, tested, agreed upon and included in the health monitoring systems currently under development by the European Commission (EC): the Directorate General for Health and Consumer Affairs (DG SANCO); the Statistical Office of the European Communities (EUROSTAT), etc. The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study group plans, among other things, to describe the health-related fitness of adolescents in a number of European countries. Experiences from AVENA and EYHS will be taken advantage of. This review summarises results and experiences from the developmental work so far and suggests a set of health-related fitness tests for possible use in future health information systems.On behalf of the HELENA Study Group 相似文献
29.
Andrej M. Grjibovski Patrick Bergman Maria Hagströmer Anita Hurtig-Wennlöf Dirk Meusel Francisco B. Ortega Emma Patterson Eric Poortvliet Nico Rizzo Jonatan R. Ruiz Juila Wärnberg Michael Sjöström 《Zeitschrift fur Gesundheitswissenschaften》2006,14(5):261-268
The European Youth Heart Study (EYHS) addresses cardiovascular disease risk factors and their determinants in European children and adolescents. The Swedish part of the study began with cross-sectional data collection in 9- and 15-year-old schoolchildren in 1998–1999 (EYHS-I). Repeated observations of the key indicators were performed in 2004–2005 (EYHS-II). The purpose of this study was to assess potential dropout effects in EYHS-II. Participants in both EYHS-I and EYHS-II (n=459) were compared with dropouts who participated only in the EYHS-I (n=678) in relation to baseline physical activity, cardiorespiratory fitness and socioeconomic and anthropometric characteristics. Bivariate comparisons were performed using chi-square tests and gamma tests for nominal and ordinal data, respectively. Continuous data were compared by t tests and Mann−Whitney tests depending on the distribution. The Bonferroni correction was used to control for multiple hypothesis testing. Multiple logistic regression with backward elimination of variables was applied to study independent effects of variables on the probability of becoming a dropout. Analyses were performed separately for the younger and older age groups. The dropout proportion in EYHS-II was 60%. Subjects from the older age group were less likely to participate in the follow-up study (32% vs. 50%, p<0.001). In bivariate analyses, only maternal education was associated with dropout rates in the younger age group after Bonferroni correction. Males were more likely to drop out in both younger [odds ratio (OR)=1.72; 95% confidence interval (CI): 1.10, 2.96] and older (OR=1.96; 95% CI: 1.09, 3.54) age groups while basic maternal education was associated with outcome only in the younger group (OR=4.31; 95% CI: 1.78, 2.95) in regression analysis. The Swedish EYHS-II had high dropout rate after EYHS-I, but the dropouts did not differ from the participants in relation to physical activity, physical fitness, and anthropometric indices. Males were more likely to drop out than were females in both age groups. Differential dropout in relation to maternal education was observed in the younger age group. 相似文献
30.