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1.
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   

2.
In 1967, some hematologists who were inspired by Barbey d’Aurevilly’s novel, “A story without a name”, described the syndrome of Lasthénie de Ferjol: recurrent anemia resulting from voluntarily provoked hemorrhages. We used the same novel as a basis for studying the mother-daughter relationship. Madame de Ferjol is widowed, and lives a reclusive life with her only daughter, Lasthénie, until such time as a capuchin priest enters their life during Lent. This unexpected encounter with sexuality (Lasthénie becomes pregnant) has a marked effect upon the young woman; she withdraws into total silence, and displays self-mutilating behavior (provoked bouts of anemia) which leads to her death and to that of her unborn child. In this tale, we see a paradigm of the mother-child relationship that has already been observed in anorexia nervosa. Mother and daughter are caught up in a narcissistic dyad fom which neither is able to extricate herself. The mother remains in a pathological state of mourning, and we put forward the hypothesis that this dead mother is affected by a melancholic process in which her hatred is projected onto her daughter. Finally, we have attempted to examine the connections between hysteria and anorexia nervosa, as in this story rivalry between mother and daughter also plays a role, and in which sexuality—therefore involving a third party—is unmentionable.  相似文献   
3.
Cholesterol distribution in tumoral tissues and lipid composition in the plasma compartment were determined in patients affected by different histologic types of lung cancer. The results showed that tumoral lung tissues contained 2-fold more total cholesterol and 3.5-fold more esterified cholesterol than normal lung tissues. In the patients the alterations in intracellular cholesterol were also associated with peculiar changes in cholesterol distribution in the plasma compartment. Serum high-density lipoprotein (HDL) cholesterol levels were markedly lower in than in controls. No significant changes in other lipid parameters were observed in these patients. We suggest that the reduced levels of serum HDL cholesterol observed in patients with lung tumors may be a consequence of the disease, probably mediated by the greater utilization of cholesterol for new membrane biogenesis and by the accumulation of esterified cholesterol in tumoral tissues.  相似文献   
4.
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   
5.
Parathyroid hormone-related protein (PTHrP) plays an important role in the pathogenesis of malignant hypercalcemia by stimulating bone resorption and/or renal tubular reabsorption of calcium. In cultured cancer cells, its production can be influenced by various factors or ions, but the regulation of its production is still poorly understood. We investigated the effects of stimulators of cAMP synthesis on PTHrP release by a human lung squamous-carcinoma cell line (BEN). In supervised cells grown on microcarrier beads, PTHrP production was significantly increased after incubation with calcitonin for only 20 min. The release of immunoreactive and bioactive PTHrP was increased by incubating the cells with forskolin, 3-isobutyl-I-methylxanthine or dibutyryl cAMP even in the presence of the protein-synthesis inhibitor cycloheximide for 6 hr. The calcitonin-mediated stimulation was not accompanied by. concomitant changes in PTHrP mRNA. The microfilament-disrupter cytocha-lasin D was shown to enhance the basal and calcitonin-induced production of PTHrP. These results indicate that stimulators of cAMP synthesis enhanced PTHrP release by BEN cells.  相似文献   
6.
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   
7.
With the aim of evaluating the possible functional modifications of both D1 and D2 dopamine receptor subpopulations after repeated administration of neuroleptics, the ability of selective D1 and D2 dopamine agonists to stimulate or inhibit, respectively, the activity of adenylate cyclase in the striatum and nucleus accumbens of rats treated with either saline or haloperidol for 21 days, was studied. It was found that stimulation of the activity of adenylate cyclase elicited by the selective D1 receptor agonist SKF 38393 was significantly greater in homogenates of striatum in rats treated with haloperidol, than in those of saline-treated rats. Similarly, the inhibitory effect on the activity of the enzyme elicited by the selective D2 agonist bromocriptine was much more evident in homogenates of the striatum from rats treated with neuroleptic than in those from saline-treated rats. When dopamine, sodium fluoride (NaF), or 5-guanylyl imidodiphosphate (Gpp(NH)p), were used as agonists to stimulate the activity of adenylate cyclase, the amount of cyclic AMP formed appeared the same in rats treated with haloperidol or saline. Dopamine receptors in nucleus accumbens behaved like those in the striatum in the pattern of modifications after repeated administration of haloperidol. Indeed, the inhibitory effect elicited by bromocriptine, as well as the stimulatory effect elicited by SKF 38393, was much more evident in nucleus accumbens from rats treated with haloperidol than in that from controls, whereas activation of adenylate cyclase induced by dopamine and sodium fluoride was similar in both experimental groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
Clostridium sordellii is an infrequent human pathogen. It has been demonstrated to be occasionally responsible for myonecrosis or gas gangrene. Interestingly, in the obstetric literature, some cases of postpartum maternal deaths have been associated with C sordellii infection causing a rapidly lethal toxin mediated syndrome. This is the first reported case of postpartum death in a 29 year old woman, in which a toxigenic C sordellii was isolated from the patient's blood antemortem during the fatal toxic shock, strongly indicating its role in this rare syndrome.  相似文献   
9.
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   
10.
BACKGROUND: Sperm DNA integrity (SDI) is an important factor in the prognosis of male fertility. Here we compare the toluidine blue (TB) image cytometry test, recently proposed by us for SDI assessment, with two other tests-the sperm chromatin structure assay (SCSA) and the terminal nick-end labelling (TUNEL) assay. METHODS: Sperm samples from 35 men were evaluated for standard sperm parameters and subjected to the TB test and SCSA. Eighteen of the 35 samples were also subjected to the TUNEL assay. RESULTS: The proportion of sperm cells with abnormal DNA integrity assayed by the TB test correlated strongly with the proportion of abnormal cells detected by the SCSA and TUNEL assay (rho=-0.84 and rho=0.80, P<0.001, respectively). Furthermore, the fractions of abnormal cells by the TB test corresponded closely to the sum of two SCSA parameters, the DNA fragmentation index (DFI) and the fraction of highly DNA-stainable cells (HDS) (medians 33.0 versus 32.0%, P=0.6). CONCLUSIONS: Abnormal cells in a TB test correspond to the sum of DFI and HDS fractions in the SCSA. TB-positive cells may represent sperm with fragmented DNA and/or abnormal chromatin structure. Because the TB test is an easy and inexpensive method, its potential use as a routine test for sperm DNA integrity, complementary to standard semen parameters, should be investigated further.  相似文献   
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