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101.
Strength training can improve myriad health parameters in elderly cohorts. Although potentially more appropriate for the elderly, low-load resistance training protocols have been less investigated. We aimed to examine the effects of 12 weeks of chair-based, low-load resistance training with elastic band (EBT) on functional fitness and metabolic biomarkers in older women. One hundred sixty-eight women were allocated randomly to an elastic band resistance training (EBT, n = 86, 75.7 ± 8.9 years, 71.3 ± 12.2 kg) or a control group (CON, n = 82, 74.5 ± 8.2years, 70.6 ± 12.0 kg). RT protocol consisted of periodized chair-based, low-load whole-body resistance exercises (2 sets, 12-15 repetitions, 40-60% of one repetition maximum-1RM) using an elastic band, twice weekly for 12 weeks. The resistance training program was generally designed to maintain internal load over time, provided with increasing intensity using various elastic bands (Thera-Band). Functional fitness (30-s Chair Stand,30-s Arm Curl, 2-min Step Test, Chair Sit-and-Reach, Back Scratch, 8-Foot Up-and-Go, Handgrip Strength) and metabolic markers (Fasting blood glucose, triglycerides, total cholesterol, high (HDL) and low (LDL) density lipoprotein) were measured before and after the training period. To detect pre/post intervention changes and between group- differences 2x2 repeated measures ANOVA was applied. Significant improvements over time for all fitness variables for EBT comparing to CON were obtained (F = 12.78, p < 0.05 for 30-s Chair Stand; F = 14.04, p < 0.05 for 30-s Arm Curl; F = 5.18, p < 0.05 for 2-min Step Test; F = 10.90, p < 0.05 for Chair Sit-and-Reach; F = 16.57, p < 0.05 for Back Scratch; F = 11.79, p < 0.05 for 8-foot Up-and-Go; and F = 29.25, p < 0.05 for Handgrip Strength). In addition, significant improvements over time for all but one (triglycerides) biomarkers for EBT comparing to CON were obtained (F = 7.30, p < 0.05 for blood sugar levels; F = 13.36, p < 0.05 for total cholesterol; F = 8.61, p < 0.05 for HDL; and F = 11.53, p < 0.05 for LDL). Furthermore, the participants’ adherence to training sessions of over 90% was reported. In conclusion, 12 weeks of EBT is safe and beneficial for improving health-related fitness and metabolic biomarkers in older women and seems to be viable model to ensure a high training adherence rate.Key points
  • EBT lead to a significant improvement in glucose, total cholesterol, HDL and LDL in older women.
  • EBT lead to a significant increase in cardiorespiratory fitness, handgrip strength, lower- body strength and flexibility, upper-body strength and flexibility and agility in older women.
  • EBT seems to be viable model to ensure high training adherence rate.
Key words: Aging, lipoproteins, low-intensity strength training, physical function  相似文献   
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The efficiency of human recombinant epoetin in alleviating anemia in hemodialyzed patients has been well documented. However, the effects of rhEPO therapy in correction of antioxidant capacity are not completely explained. In this study we examined both extracellular (plasma) and intracellular (red blood cells) antioxidant potential in hemodialyzed patients before and after three and six months of epoetin treatment by evaluating markers of oxidative stress (malondialdehyde) and antioxidant capacity (thiol groups, superoxide dismutase, and glutathione peroxidase). Six months of treatment with epoetin was followed by significant increases in thiol groups, superoxide dismutase and glutathione peroxidase activities in both plasma and red blood cells of hemodialyzed patients. Hence, during accelerated erythropoiesis, an increase in the number of young hematopoietic cells may replenish erythrocyte superoxide dismutase and glutathione peroxidase activity. However, the consequences of an imbalance between enzymatic antioxidant system (higher superoxide dismutase and lower glutathione peroxidase activity) that exists in these patients are the very high red blood cell and plasma malondialdehyde levels. These results suggest that, in spite of epoetin treatment and improvement in red blood cells and plasma antioxidant capacity, the production of reactive oxygen species overwhelms the intracellular and extracellular antioxidant capacity.  相似文献   
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We investigated the relationship between immunological and behavioral changes during ageing in Dark Agouti female rats. Results showed that ageing was associated with decreased exploratory behavior and increased emotionality (open field test) and decreased pain perception (writhing assay), but not with altered depression-like behavior (forced swim test). The observed behavioral changes were paralleled with decreased innate immunity in middle-aged and old rats, as revealed by reduced peroxide production of peritoneal macrophages; and decreased specific immunity, measured by the plaque-forming cell response, in old rats in comparison with young rats. Correlation analyses between behavioral and immune parameters demonstrated a significant correlation between the lines crossed in the open field test and the plaque-forming cell response. Taken together, the demonstrated age-dependent association between exploratory behavior and specific immune response suggests a senescent decline of a common neuroimmune regulatory mechanism.  相似文献   
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BACKGROUND: The established treatment modality of acute Stanford type A dissection includes repair of the ascending aorta and various portions of the aortic arch, whereas the descending aorta is left untreated. We report a simultaneous approach of open repair of the ascending aorta with transluminal stent grafting of the descending aorta to minimize the consequences of an untreated descending aorta. METHODS: From April 2001 to February 2002, 8 consecutive patients (3 women [37.5%] and 5 men [62.5%]) with a mean age of 55.7 years (range, 45 to 70 years) were intended to be treated with the combined method of surgical repair of the ascending aorta and transluminal stent grafting into the descending aorta during the period of deep hypothermic circulatory arrest. Circulatory arrest time ranged between 30 and 67 minutes (average, 38.8 minutes). Specially designed Talent stent grafts (32 to 40 mm in diameter, length 13 cm) were inserted under direct vision and deployed with the proximal end at the origin of the left subclavian artery. RESULTS: Intraoperative stent graft placement was successful in 7 patients (87.5%). Because of severe kinking of the distal arch, stent insertion failed in 1 patient (12.5%). One patient with a history of preoperative stroke in the middle cerebral artery died because of intracerebral bleeding on postoperative day 2, resulting in an in-hospital mortality of 12.5%. Mean intensive care unit stay was 6.4 days (range, 2 to 21 days) and overall hospital stay was 18.2 days (range, 7 to 33 days). Completion computed tomographic scans revealed complete thrombosis of the false lumen in 2 patients and partial thrombosis in 4 patients. Follow-up was complete and ranged from 1 to 9 months (mean, 5.4 months). CONCLUSIONS: This preliminary study shows that combined surgical and endovascular treatment of acute type A dissection is feasible, and at least partial thrombosis of the false lumen can be achieved, potentially minimizing the risk of further dilatation or rupture. Additionally, the stent graft expands the otherwise sickle-shaped true lumen, thereby ameliorating distal aortic perfusion. Long-term results are warranted to demonstrate the effectiveness of this new combined treatment modality.  相似文献   
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BACKGROUND: The VAC system (vacuum-assisted wound closure) is a noninvasive active therapy to promote healing in difficult wounds that fail to respond to established treatment modalities. The system is based on the application of negative pressure by controlled suction to the wound surface. The method was introduced into clinical practice in 1996. Since then, numerous studies proved the effectiveness of the VAC System on microcirculation and the promotion of granulation tissue proliferation. METHODS: Eleven patients (5 men, 6 women) with a median age of 64.4 years (range 50 to 78 years) with sternal wound infection after cardiac surgery (coronary artery bypass grafting = 5, aortic valve replacement = 5, ascending aortic replacement = 1) were fitted with the VAC system by the time of initial surgical debridement. RESULTS: Complete healing was achieved in all patients. The VAC system was removed after a mean of 9.3 days (range 4 to 15 days), when systemic signs of infection resolved and quantitative cultures were negative. In 6 patients (54.5%), the VAC system was used as a bridge to reconstructive surgery with a pectoralis muscle flap, and in the remaining 5 patients (45.5%), primary wound closure could be achieved. Intensive care unit stay ranged from 1 to 4 days (median 1 day). Duration of hospital stay varied from 13 to 45 days (median 30 days). In-hospital mortality was 0%, and 30-day survival was 100%. CONCLUSIONS: The VAC system can be considered as an effective and safe adjunct to conventional and established treatment modalities for the therapy of sternal wound infections after cardiac surgery.  相似文献   
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