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71.

Background

We have previously reported on the benefits of Pre-Surgical Exercise Training (PreSET) on physical fitness and social interactions in subjects awaiting bariatric surgery (BS). However, data are needed to know whether these benefits are maintained post-BS.

Objectives

The purpose of this paper was to evaluate the effect of PreSET on physical activity (PA) level, physical fitness, PA barriers, and quality of life (QoL) 1 year (1-Y) after BS.

Methods

Of the 30 participants randomized into two groups (PreSET and usual care), 25 were included in the final analysis. One year after BS, time spent in different PA intensities and number of steps were assessed with an accelerometer. Before BS and until 1-Y after BS, physical fitness was assessed with symptom-limited cardiac exercise test, 6-min walk test (6MWT), and sit-to-stand, half-squat, and arm curl tests. QoL, PA barriers, and PA level were evaluated with questionnaires.

Results

The number of steps (7460 vs 4287) and time spent in light (3.2 vs 2.2 h/day) and moderate (0.6 vs 0.3 h/day) PA were higher in the PreSET group 1-Y after BS. The changes in 6MWT heart cost (1.3 vs 0.6 m/beats/min), half-squat test (38.8 vs 10.3 s), and BMI (? 16.8 vs ? 13.5 kg/m2) were significantly greater in the PreSET group compared to those in the usual care group. No other significant difference between groups was observed.

Conclusion

The addition of the PreSET to individual lifestyle counseling seems effective to improve PA level and submaximal physical fitness 1-Y after BS. Studies with larger cohorts are now required to confirm these results.The trial was registered at clinicaltrials.gov (NCT01452230).
  相似文献   
72.
OBJECTIVE: The aim of this study was to evaluate the ability of an Er:YAG laser (2960nm) to prepare class V cavities as compared with rotary instruments. MATERIALS AND METHODS: Twenty-six freshly extracted human molars were selected and randomly distributed in two groups. Non standardized class V cavities were prepared using (group 1) a diamond bur for enamel, plus a tungsten bur for dentin with water irrigation and (group 2) an Er:YAG laser (output parameters, enamel: 1000 mJ, 12Hz, dentin: 500 mJ, 20Hz) with a continuous flow of water. RESULTS: The SEM examination revealed characteristic micro-irregularities of the lased samples as compared with the conventional prepared cavities: group 1, the walls of the cavities were slightly curved and a smear layer plus muds covered peripheric walls as well as the depth of the cavity; rare dentinal tubules were opened; linear and circular surface irregularities were observed on the dentin; and group 2, the walls of the cavities were irregular, jagged; photo-ablation creates a real cleavage of hydroxyapatite prisms with respect to the enamel prism pathway; an homogeneous dentin with opened dentinal tubules covered the depth of the cavities; intertubular dentin is selectively more ablated than Er-YAG the peritubular dentin. CONCLUSIONS: Jagged outline as well as opened dentinal tubules are the main characteristics of the Er-YAG prepared class V cavities. Further investigations (ulstrastructural, histochemical properties of the lased dentin, resistance to traction of bonded resins) should be conducted.  相似文献   
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The integration of chemistry and molecular biology with imaging is providing some of the most exciting opportunities in the treatment of cancer. The field of theranostic imaging, where diagnosis is combined with therapy, is particularly suitable for a disease as complex as cancer, especially now that genomic and proteomic profiling can provide an extensive 'fingerprint' of each tumor. Using this information, theranostic agents can be shaped for personalized treatment to target specific compartments, such as the tumor microenvironment (TME), whilst minimizing damage to normal tissue. These theranostic agents can also be used to target multiple pathways or networks by incorporating multiple small interfering RNAs (siRNAs) within a single agent. A decade ago genetic alterations were the primary focus in cancer research. Now it is apparent that the tumor physiological microenvironment, interactions between cancer cells and stromal cells, such as endothelial cells, fibroblasts and macrophages, the extracellular matrix (ECM), and a host of secreted factors and cytokines, influence progression to metastatic disease, aggressiveness and the response of the disease to treatment. In this review, we outline some of the characteristics of the TME, describe the theranostic agents currently available to target the TME and discuss the unique opportunities the TME provides for the design of novel theranostic agents for cancer therapy.  相似文献   
76.
Allostatic load represents the strain that chronic stress exerts on interconnected biological systems. Associated algorithms are related to numerous deleterious physical outcomes in older populations, and yet few studies have assessed associations to mental health outcomes like geriatric depression. Using data from the Douglas Hospital Longitudinal Study of Normal and Pathological Aging, we assessed whether using an allostatic load index derived from seven biomarkers could detect self-rated depressive symptoms in 58 healthy older adults followed longitudinally over a 6-year period. Our results revealed that increased allostatic load was associated with increased depressive symptoms on the same year of assessment. After 3 years, AL was prospectively associated with depressive symptoms, but entering age and sex as covariates attenuated this effect to a trend. Only age emerged as a significant predictor of depressive symptoms over 6 years. These findings suggest that increased AL in older age is only associated with depressive symptomatology acutely. Over longer periods of time, however, the physical and psychological sequelae of advanced age may contribute to increased depressive symptoms via pathways otherwise undetectable using allostatic load indices of sub-clinical physiological dysregulations.  相似文献   
77.
Weight gain and appetite regulation are complex interplays between internal and external cues. Our aim was to investigate the association of eating behaviors with ghrelin taking into account lifestyle. We conducted a cross-sectional analysis in a sample of first-year university students at the Université de Sherbrooke. We collected medical history, anthropometric measurements, vital signs, fitness index, and fasting blood samples. Questionnaires included a lifestyle questionnaire and the Three-Factor Eating Questionnaire (TFEQ) estimating dietary restraint, disinhibition and hunger. We recruited 308 participants aged 20.7 ± 3.2 years and a mean BMI of 23.3 ± 3.4 kg/m2. Hunger score was significantly associated with ghrelin levels (r = 0.11, P < 0.05). In women, this association was independent of age, BMI, dietary and lifestyle factors (P = 0.02). The association between ghrelin level and hunger score was observable in leaner individuals (r = 0.28, p < 0.0001) but not in heavier individuals (r = − 0.08, p = 0.34; stratified by BMI < vs > 22.6 kg/m2). Restraint (R) and disinhibition (D) were not associated with ghrelin levels. The three eating behaviors demonstrated expected correlations with lifestyle supporting the validity of the TFEQ in this cohort. In conclusion, we demonstrated that ghrelin, a biological marker, is associated with self-reported perception of hunger, independently of anthropometric measures and lifestyle.  相似文献   
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79.
Gliotic scar formation and angiogenesis are two biological events involved in the tissue reparative process generally occurring in the brain after mechanically induced injury, ischemia or cerebral tumor development. For the first time, in this study, neo-vascularization and glial scar formation were investigated in the brain of soman-poisoned mice over a 3-month period after nerve agent exposure (1.2 LD50 of soman). Using anti-claudin-5 and anti-vascular endothelial growth factor (VEGF) immunostaining techniques on brain sections, blood vessels were quantified and VEGF expression was verified to appraise the level of neo-angiogenesis induced in damaged brain areas. Furthermore, glial scar formation and neuropathology were estimated over time in the same injured brain regions by anti-glial fibrillary acidic protein (GFAP) immunohistochemistry and hemalun-phloxin (H&P) dye staining, respectively. VEGF over-expression was noticed on post-soman day 3 in lesioned areas such as the hippocampal CA1 field and amygdala. This was followed by an increase in the quantity of mature blood vessels, 3 months after soman poisoning, in the same brain areas. On the other hand, massive astroglial cell activation was demonstrated on post-soman day 8. Reactive astroglial cells were located only in damaged cerebral regions where H&P-stained eosinophilic neurons were found. For longer experimental times, astroglial response slowly decreased overtime but remained detectable on post-soman day 90 in some discrete brain regions (i.e. CA1 field and amygdala) evidencing the formation of a glial scar. In this study, we discuss the key role of VEGF in the angiogenic process and in the glial or neuronal response induced by soman poisoning.  相似文献   
80.
Synapses are formed and stabilized by concerted interactions of pre-, intra-, and post-synaptic components; however, the precise nature of the intrasynaptic components in the CNS remains obscure. Potential intrasynaptic components include extracellular matrix molecules such as laminins; here, we isolate beta2-containing laminins, including perhaps laminins 13 (alpha3beta2gamma3) and 14 (alpha4beta2gamma3), from CNS synaptosomes suggesting a role for these molecules in synaptic organization. Indeed, hippocampal synapses that form in vivo in the absence of these laminins are malformed at the ultrastructural level and this malformation is replicated in synapses formed in vitro, where laminins are provided largely by the post-synaptic neuron. This recapitulation of the in vivo function of laminins in vitro suggests that the malformations are a direct consequence of the removal of laminins from the synapse. Together, these results support a role for neuronal laminins in the structural integrity of central synapses.  相似文献   
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