Objective: To examine (i) the associations between physical activity dimensions, cardiorespiratory fitness and body composition and, (ii) the associations between physical activity dimensions, cardiorespiratory fitness, body composition and biomarkers of cardiometabolic health in persons with spinal cord injury (SCI).
Methods: A cross-sectional prospective cohort study with 7-day follow-up was conducted. Body composition, cardiorespiratory fitness and biomarkers of cardiometabolic health were measured in thirty-three participants with SCI (> 1 year post injury). Physical activity dimensions were objectively assessed over 7-days.
Results: Activity energy expenditure (r =.43), physical activity level (r =.39), and moderate-to-vigorous physical activity (MVPA) (r =.48) were significantly (P < 0.001) associated with absolute (L/min) peak oxygen uptake (?O2 peak). ?O2 peak was significantly higher in persons performing ≥150 MVPA minutes/week compared to <40 minutes/week (P?=?0.003). Individual physical activity dimensions were not significantly associated with biomarkers of cardiometabolic health. However, body composition characteristics (BMI, waist and hip circumference) showed significant (P < 0.04), moderate (r >.30) associations with parameters of metabolic regulation, lipid profiles and inflammatory biomarkers. Relative ?O2 peak (ml/kg/min) was moderately associated with only insulin sensitivity (r?=?0.37, P?=?0.03).
Conclusions: Physical activity dimensions are associated with cardiorespiratory fitness; however, stronger and more consistent associations suggest that poor cardiometabolic health is associated with higher body fat content. Given these findings, the regulation of energy balance should be an important consideration for researchers and clinicians looking to improve cardiometabolic health in persons with SCI. 相似文献
Whether peak bone mass is low among children with fractures remains uncertain. In a cohort of 125 girls followed over 8.5 years, 42 subjects reported 58 fractures. Among those, BMC gain at multiple sites and vertebral bone size at pubertal maturity were significantly decreased. Hence, childhood fractures may be markers of low peak bone mass acquisition and persistent skeletal fragility. INTRODUCTION: Fractures in childhood may result from a deficit in bone mass accrual during rapid longitudinal growth. Whether low bone mass persists beyond this period however remains unknown. MATERIALS AND METHODS: BMC at the spine, radius, hip, and femur diaphysis was prospectively measured over 8.5 years in 125 girls using DXA. Differences in bone mass and size between girls with and without fractures were analyzed using nonparametric tests. The contribution of genetic factors was evaluated by mother-daughter correlations and that of calcium intake by Cox proportional hazard models. RESULTS: Fifty-eight fractures occurred in 42 among 125 girls (cumulative incidence, 46.4%), one-half of all fractures affecting the forearm and wrist. Girls with and without fractures had similar age, height, weight. and calcium intake at all time-points. Before and during early puberty, BMC and width of the radius diaphysis was lower in the fracture compared with no-fracture group (p < 0.05), whereas aBMD and BMAD were similar in the two groups. At pubertal maturity (Tanner's stage 5, mean age +/- SD, 16.4 +/- 0.5 years), BMC at the ultradistal radius (UD Rad.), femur trochanter, and lumbar spine (LS), and LS projected bone area were all significantly lower in girls with fractures. Throughout puberty, BMC gain at these sites was also decreased in the fracture group (LS, -8.0%, p = 0.015; UD Rad., -12.0%, p = 0.004; trochanter, -8.4%, p = 0.05 versus no fractures). BMC was highly correlated between prepuberty and pubertal maturity (R = 0.54-0.81) and between mature daughters and their mothers (R = 0.32-0.46). Calcium intake was not related to fracture risk. CONCLUSIONS: Girls with fractures have decreased bone mass gain in the axial and appendicular skeleton and reduced vertebral bone size when reaching pubertal maturity. Taken together with the evidence of tracking and heritability for BMC, these observations indicate that childhood fractures may be markers for low peak bone mass and persistent bone fragility. 相似文献
We compared and contrasted the mechanism of action for the cysteine knot protein subfamily, Wise and Sost (Sclerostin). Our data suggest that functional interactions between Sost or Wise and LRP5/LRP6 have the potential to regulate bone deposition by modulating the Wnt pathway. INTRODUCTION: The human disease sclerosteosis exhibits an increase in bone mass thought to be caused by hyperactive osteoblasts. Sclerostin, SOST, the gene affected in this disease, has been postulated to exert its activity by functioning as a BMP antagonist. However, recent evidence indicates that SOST is highly related to Wise, which can also modulate the Wnt pathway by binding to LRP5 and LRP6. MATERIALS AND METHODS: For this study, we used cell culture to test the BMP and Wnt activity function of both Wise and Sost. In addition, we used Xenopus in vivo Wnt assays along with Xenopus in vitro Wnt assays to support our cell culture results. Epitope tagged cell supernatants containing either Sost or soluble mutant or wildtype LRP5/LRP6 were used for immunoprecipitation. Sost immunoprecipitation results were confirmed in vivo using cell culture. Finally, to support our in vitro data, we co-localized Sost, Wise, LRP5, and LRP6 in mouse long bone sections. Results: In this study, we report in vitro and in vivo evidence to show that Sost physically interacts with Lrp5 and Lrp6 and inhibits the canonical Wnt signaling pathway. Furthermore, using in vitro and in vivo assays, we showed that a variant of LRP5 (LRP5(G171V)) known to cause the human high bone mass (HBM) trait and a homologous change in LRP6 (LRP6(G158V)) abolished protein interactions with Sost. We used variants of Sost amino acids to further identify the contact points between Sost and LRP6. In Xenopus and mammalian cell culture assays, we showed that SOST is able to attenuate Wnt signaling and that this attenuation can be rescued by the addition of alpha-Sost antibodies or by the introduction of single amino acid substitution that alter its binding to LRP6. Sost differs from Wise in that it is unable to stimulate Wnt signaling. Using immunohistochemistry, we found that Sost and Wise are co-localized to osteoblasts, along with LRP5 and LRP6. CONCLUSIONS: Our data suggest that functional interactions between Sost or Wise and LRPs have the potential to regulate bone deposition by modulating Wnt signaling. 相似文献
This bibliographic essay's initial focus is on publications reflecting European concern with the ethical implications of reproductive technologies. Titles by P. Verspieren, the Institut Catholique de Lyon, C. Lefèvre, E. Loumaye and J-F. Malherbe, and J-L. Baudouin and C. Labrusse-Riou are briefly discussed. Also mentioned are recently published works on biomedical technologies by B. Edelman, M-A. Hermite, Labrusse-Riou, and M. Remond-Gouilloud; on the social impact of science by G. Hottois, J. DeVooght, R. Rasmont, and P. Van Gansen; on medical ethics by C. Ambroselli, and by Malherbe; on AIDS by E. Hirsch, by E. Conan, and by Malherbe and S. Zorrilla. All cited titles are in French. 相似文献
Multiplication of data sources within heterogeneous healthcare information systems always results in redundant information,
split among multiple databases. Our objective is to detect exact and approximate duplicates within identity records, in order
to attain a better quality of information and to permit cross-linkage among stand-alone and clustered databases. Furthermore,
we need to assist human decision making, by computing a value reflecting identity proximity. 相似文献
Adherence of the opportunistic fungus Aspergillus fumigatus to the extracellular matrix components is considered a crucial step in the establishment of the infection. Given the high carbohydrate content of these glycoproteins and the role of carbohydrate-protein interactions in numerous adherence processes, the presence of a lectin in A. fumigatus was investigated. Different fungal extracts obtained by sonication or grinding in liquid nitrogen from resting or swollen conidia, as well as from germ tubes and mycelium, were tested by hemagglutination assays using rabbit erythrocytes. A lectin activity was recovered in all the extracts tested. However, sonication of resting conidia resulted in the highest specific activity. Purification of the lectin was achieved by gel filtration followed by ion-exchange and hydrophobic-interaction chromatographies. Analysis of the purified lectin by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed an apparent molecular mass of 32 kDa, which is similar to that of the alkaline protease already identified from different strains of A. fumigatus. However, as evidenced by the use of an alkaline protease-deficient mutant, the two activities were supported by distinct proteins. In addition, hemagglutination inhibition experiments using different saccharides and glycoproteins demonstrated the specificity of the lectin for sialic acid residues. Together these results suggest that this lectin may contribute to the attachment of conidia to the extracellular matrix components through the recognition of the numerous terminal sialic acid residues of their carbohydrate chains. 相似文献
1. Renal function was compared in dogs before and after denervation, with normal or reduced glomerular filtration rate (GFR). GFR was reduced by one of two means, aortic clamping or injection of plastic microspheres into one renal artery.
2. The data showed that the tubular rejection fraction of denervated kidneys increased at a time when the same value for the control kidney decreased, indicating that denervation diuresis is not simply a result of increased filtered load of Na and water.
3. Changes in excretion after aortic clamping are not due solely to reduced filtered load. A reduction in renal blood pressure itself appears to have a direct effect on Na transport since Na excretion was significantly decreased before there were any changes in GFR, renal plasma flow and urine volume.
4. When GFR in a denervated kidney was reduced by microsphere injection it was demonstrated that a significant natriuresis (UNa V) and diuresis (V) occurred when. GFR was reduced by as much as 40%.
5. These experiments support the hypothesis that denervation diuresis does not result solely from increased filtered load, but entails altered Na transport.
Metronidazole resistance among Prevotella spp. is rare. We report here the first case of bacteremia due to a high-level metronidazole-resistant Prevotella sp. responsible for treatment failure. 相似文献
Most mouse models of hepatocellular carcinoma have expressed growth factors and oncogenes under the control of a liver-specific promoter. In contrast, we describe here the formation of liver tumors in transgenic mice overexpressing human fibroblast growth factor 19 (FGF19) in skeletal muscle. FGF19 transgenic mice had elevated hepatic alpha-fetoprotein mRNA as early as 2 months of age, and hepatocellular carcinomas were evident by 10 months of age. Increased proliferation of pericentral hepatocytes was demonstrated by 5-bromo-2'-deoxyuridine incorporation in the FGF19 transgenic mice before tumor formation and in nontransgenic mice injected with recombinant FGF19 protein. Areas of small cell dysplasia were initially evident pericentrally, and dysplastic/neoplastic foci throughout the hepatic lobule were glutamine synthetase-positive, suggestive of a pericentral origin. Consistent with chronic activation of the Wingless/Wnt pathway, 44% of the hepatocellular tumors from FGF19 transgenic mice had nuclear staining for beta-catenin. Sequencing of the tumor DNA encoding beta-catenin revealed point mutations that resulted in amino acid substitutions. These findings suggest a previously unknown role for FGF19 in hepatocellular carcinomas. 相似文献
A valine to isoleucine mutation at residue 180 was identified in a French patient with Creutzfeldt-Jakob disease (CJD). The mutation is located in the close vicinity of one of the two N-glycosylation sites of the cellular prion protein (PrPC). Western blot analysis revealed accumulation in the brain of the pathogenic proteinase K-resistant PrP (PrPSc) isoform with the notable absence of the diglycosylated band. The mutant protein expressed in CHO cells was correctly glycosylated, suggesting that the atypical glycosylation pattern of PrPSc was not due to the mutation at position 180. These results suggest that the diglycosylated form of the mutant PrP180I prevents its conversion into the pathogenic mutant form PrPSc180I, supporting a central role of N-linked glycan chains in the PrP conversion process. 相似文献