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991.
Matthew I. Bury Natalie J. Fuller Jay W. Meisner Matthias D. Hofer Matthew J. Webber Lesley W. Chow Sheba Prasad Hatim Thaker Xuan Yue Vani S. Menon Edward C. Diaz Samuel I. Stupp Earl Y. Cheng Arun K. Sharma 《Biomaterials》2014
Current attempts at tissue regeneration utilizing synthetic and decellularized biologic-based materials have typically been met in part by innate immune responses in the form of a robust inflammatory reaction at the site of implantation or grafting. This can ultimately lead to tissue fibrosis with direct negative impact on tissue growth, development, and function. In order to temper the innate inflammatory response, anti-inflammatory signals were incorporated through display on self-assembling peptide nanofibers to promote tissue healing and subsequent graft compliance throughout the regenerative process. Utilizing an established urinary bladder augmentation model, the highly pro-inflammatory biologic scaffold (decellularized small intestinal submucosa) was treated with anti-inflammatory peptide amphiphiles (AIF-PAs) or control peptide amphiphiles and used for augmentation. Significant regenerative advantages of the AIF-PAs were observed including potent angiogenic responses, limited tissue collagen accumulation, and the modulation of macrophage and neutrophil responses in regenerated bladder tissue. Upon further characterization, a reduction in the levels of M2 macrophages was observed, but not in M1 macrophages in control groups, while treatment groups exhibited decreased levels of M1 macrophages and stabilized levels of M2 macrophages. Pro-inflammatory cytokine production was decreased while anti-inflammatory cytokines were up-regulated in treatment groups. This resulted in far fewer incidences of tissue granuloma and bladder stone formation. Finally, functional urinary bladder testing revealed greater bladder compliance and similar capacities in groups treated with AIF-PAs. Data demonstrate that AIF-PAs can alleviate galvanic innate immune responses and provide a highly conducive regenerative milieu that may be applicable in a variety of clinical settings. 相似文献
992.
This commentary will introduce lean concepts into the clinical microbiology laboratory. The practice of lean in the clinical microbiology laboratory can remove waste, increase efficiency, and reduce costs. Lean, Six Sigma, and other such management initiatives are useful tools and can provide dividends but must be accompanied by organizational leadership commitment to sustaining the lean culture in the laboratory setting and providing resources and time to work through the process. 相似文献
993.
Aisha Cortoos Elke De Valck Nathalie Pattyn Olivier Mairesse Raymond Cluydts 《International journal of psychophysiology》2014
According to the neurocognitive perspective on insomnia, conditioned arousal results in impairment of information processing, as such interfering with normal sleep processes. In the present study, evening event-related potentials N100 and P200 were evaluated to assess hyperarousal in patients with insomnia and controls. 13 patients (mean age = 40.8) with polysomnographically verified sleep disruptions and 11 good sleepers (mean age = 45.4) were included. An auditory oddball paradigm was administered the evening of the polysomnography. N100 and P200 mean amplitudes and peak latencies at Fz and Cz were analyzed as a measure of respectively general arousability and inhibition of information processing. Patients experiencing insomnia were characterized by decreased P200 amplitudes compared to good sleepers. No significant differences were found for N100 amplitudes and latencies of both ERP waves. 相似文献
994.
Vigor is a positive affect experienced at work. It refers to feelings of possessing physical strength, emotional energy, and cognitive liveliness. Accumulated evidence suggests that vigor has a protective effect on health, but the mechanisms of this link remain to be discovered. This study focused on sleep quality as one possible mechanism. We used a full-panel, longitudinal design to investigate the hypothesis that changes in vigor over time have inverse effects on insomnia and vice versa. The study was conducted on a multi-occupational sample of working adults (N = 1,414, 70 % men) at three time points (T1, T2, and T3), over a period of about 3 years. Vigor was assessed by the Shirom-Melamed Vigor Measure, while insomnia was assessed by the Brief Athens Insomnia Scale. Results of SEM-analyses, controlling for neuroticism, and other potential confounding variables, offered a strong support for the study hypotheses, indicating cross-lagged reciprocal inverse relationships between vigor and insomnia. The results suggest that vigor has a protective effect on sleep quality and that vigor might positively influence health through this pathway. 相似文献
995.
Thiago Santos Ferreira Manuella Lanzetti Marina Valente Barroso Carlos Romualdo Rueff-Barroso Cláudia Farias Benjamim Lycia de Brito-Gitirana Luís Cristóvão Porto Samuel Santos Valença 《Inflammation》2014,37(5):1355-1365
Our aim was to investigate the effects of four different statins on acute lung inflammation induced by cigarette smoke (CS). C57BL/6 male mice were divided into a control group (sham-smoked) and mice exposed to CS from 12 cigarettes/day for 5 days. Mice exposed to CS were grouped and treated with vehicle (i.p.), atorvastatin (10 mg/kg), pravastatin (10 mg/kg), rosuvastatin (5 mg/kg), or simvastatin (20 mg/kg). Treatment with statins differentially improved the pulmonary response when compared to the CS group. Atorvastatin and pravastatin demonstrated slightly effects on inflammation and oxidative stress. Rosuvastatin demonstrated the best anti-inflammatory effect, whereas simvastatin demonstrated the best antioxidant response. 相似文献
996.
Purpose
The purpose of this study was to determine self-selected speeds, metabolic rate, and gross metabolic cost during longboard skateboarding.Methods
We measured overground speed and metabolic rate while 15 experienced longboarders traveled at their self-selected slow, typical and fast speeds.Results
Mean longboarding speeds were 3.7, 4.5 and 5.1 m s?1, during slow, typical and fast trials, respectively. Mean rates of oxygen consumption were 24.1, 29.1 and 37.2 ml kg?1 min?1 and mean rates of energy expenditure were 33.5, 41.8 and 52.7 kJ min?1 at the slow, typical and fast speeds, respectively. At typical speeds, average intensity was ~8.5 METs. There was a significant positive relationship between oxygen consumption and energy expenditure versus speed (R 2 = 0.69 (P < 0.001), and R 2 = 0.78 (P < 0.001), respectively). The gross metabolic cost was ~2.2 J kg?1 m?1 at the typical speed, greater than that reported for cycling and ~50 % smaller than that of walking.Conclusion
These results suggest that longboarding is a novel form of physical activity that elicits vigorous intensity, yet is economical compared to walking. 相似文献997.
Naomi E. Brooks Samuel M. Cadena Gregory Cloutier Sonia Vega-López Ronenn Roubenoff Carmen Castaneda-Sceppa 《International journal of medical sciences》2014,11(12):1248-1257
Objective Muscle loss and metabolic changes occur with disuse [i.e. bed rest (BR)]. We hypothesized that BR would lead to a metabolically unhealthy profile defined by: increased circulating tumor necrosis factor (TNF)-α, decreased circulating insulin-like-growth-factor (IGF)-1, decreased HDL-cholesterol, and decreased muscle density (MD; measured by mid-thigh computerized tomography).Methods We investigated the metabolic profile after 28 days of BR with 8±6% energy deficit in male individuals (30-55 years) randomized to resistance exercise with amino acid supplementation (RT, n=24) or amino acid supplementation alone (EAA, n=7). Upper and lower body exercises were performed in the horizontal position. Blood samples were taken at baseline, after 28 days of BR and 14 days of recovery.Results We found a shift toward a metabolically unfavourable profile after BR [compared to baseline (BLN)] in both groups as shown by decreased HDL-cholesterol levels (EAA: BLN: 39±4 vs. BR: 32±2 mg/dL, RT: BLN: 39±1 vs. BR: 32±1 mg/dL; p<0.001) and Low MD (EAA: BLN: 27±4 vs. BR: 22±3 cm2, RT: BLN: 28±2 vs. BR: 23±2 cm2; p<0.001). A healthier metabolic profile was maintained with exercise, including NormalMD (EAA: BLN: 124±6 vs. BR: 110±5 cm2, RT: BLN: 132±3 vs. BR: 131±4 cm2; p<0.001, time-by-group); although, exercise did not completely alleviate the unfavourable metabolic changes seen with BR. Interestingly, both groups had increased plasma IGF-1 levels (EAA: BLN:168±22 vs. BR 213±20 ng/mL, RT: BLN:180±10 vs. BR: 219±13 ng/mL; p<0.001) and neither group showed TNFα changes (p>0.05).Conclusions We conclude that RT can be incorporated to potentially offset the metabolic complications of BR. 相似文献
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Ademola Olusegun Talabi Amarachukwu Chiduziem Etonyeaku Oludayo Adedapo Sowande Samuel Anu Olowookere Olusanya Adejuyigbe 《Pediatric surgery international》2014,30(11):1121-1127