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101.
Bartlett BJ Isakson P Lewerenz J Sanchez H Kotzebue RW Cumming RC Harris GL Nezis IP Schubert DR Simonsen A Finley KD 《Autophagy》2011,7(6):572-583
Suppression of macroautophagy, due to mutations or through processes linked to aging, results in the accumulation of cytoplasmic substrates that are normally eliminated by the pathway. This is a significant problem in long-lived cells like neurons, where pathway defects can result in the accumulation of aggregates containing ubiquitinated proteins. The p62/Ref(2)P family of proteins is involved in the autophagic clearance of cytoplasmic protein bodies or sequestosomes. These unique structures are closely associated with protein inclusions containing ubiquitin as well as key components of the autophagy pathway. In this study we show that detergent fractionation followed by western blot analysis of insoluble ubiquitinated proteins (IUP), mammalian p62 and its Drosophila homologue, Ref(2)P can be used to quantitatively assess the activity level of aggregate clearance (aggrephagy) in complex tissues. Using this technique we show that genetic or age-dependent changes that modify the long-term enhancement or suppression of aggrephagy can be identified. Moreover, using the Drosophila model system this method can be used to establish autophagy-dependent protein clearance profiles that are occurring under a wide range of physiological conditions including developmental, fasting and altered metabolic pathways. This technique can also be used to examine proteopathies that are associated with human disorders such as frontotemporal dementia, Huntington and Alzheimer disease. Our findings indicate that measuring IUP profiles together with an assessment of p62/Ref(2)P proteins can be used as a screening or diagnostic tool to characterize genetic and age-dependent factors that alter the long-term function of autophagy and the clearance of protein aggregates occurring within complex tissues and cells. 相似文献
102.
103.
Glykeria Patsika Eleftherios Kellis Ioannis G. AmiridisAuthor vitae 《Journal of electromyography and kinesiology》2011,21(5):689-694
The purpose of this study was to investigate the neuromuscular efficiency of women with knee osteoarthritis (OA) when performing a sit-to-stand movement and during maximum strength efforts. Twelve women with unilateral knee OA (age 60.33 ± 6.66 years, height 1.61 ± 0.05 m, mass 77.08 ± 9.2 kg) and 11 controls (age 56.54 ± 5.46 years, height 1.64 ± 0.05 m, mass 77.36 ± 13.34 kg) participated in this study. Subjects performed a sit-to-stand movement from a chair while position of center of pressure and knee angular speed were recorded. Furthermore, maximal isokinetic knee extension and flexion strength at 60°/s, 120°/s and 150°/s was measured. Surface, electromyography (EMG) from the biceps femoris (BF), vastus lateralis (VL) and vastus medialis (VM) was recorded during all tests. Analysis of variance (ANOVA) showed that during the sit-to-stand OA group demonstrated significantly lower knee angular speed (44.49 ± 9.61°/s vs. 71.68 ± 19.86°/s), a more posterior position of the center of pressure (39.20 ± 7.02% vs. 41.95 ± 2.49%) and a higher antagonist BF activation (57.13 ± 20.55% vs. 32.01 ± 19.5%) compared with controls (p < 0.05). Further, women with knee OA demonstrated a lower Moment-to-EMG ratio than controls in extension and eccentric flexion at 60°/s and 150°/s, while the opposite was found for concentric flexion at 60°/s (p < 0.05). Among other factors, the slower performance of the sit-to-stand movement in women with OA is due to a less efficient use of the knee extensor muscles (less force per unit of EMG) and, perhaps, a higher BF antagonist co-activation. This may lead subjects with OA to adopt a different movement strategy compared with controls. 相似文献
104.
Fresh minimally processed shrimps were stored under modified atmosphere packaging (60% CO2:40% N2 for MAP A and 92.9% N2:5.1% CO2:2% O2 for MAP B) for 5 days at 3 °C. Total mesophiles, H2S forming bacteria, Pseudomonas spp., Brochothrix thermosphacta, firmness, color and sensory parameters were investigated throughout the whole time of the experiment. During storage period samples stored under MAP B managed to retain firmness values close to the initial values. All microbial populations growth was suppressed by the presence of MAP A. Samples stored under MAP B managed to maintain their firmness values close to the initial ones while MAP A samples were significantly less firm (p < 0.05). 相似文献
105.
Chartoumpekis DV Habeos IG Ziros PG Psyrogiannis AI Kyriazopoulou VE Papavassiliou AG 《Molecular medicine (Cambridge, Mass.)》2011,17(7-8):736-740
Fibroblast growth factor-21 (FGF21) is a pleiotropic protein involved in glucose, lipid metabolism and energy homeostasis, with main tissues of expression being the liver and adipose tissue. Brown adipose tissue (BAT) is responsible for cold-induced thermogenesis in rodents. The role of FGF21 in BAT biology has not been investigated. In the present study, wild-type C57BL/6J mice as well as a brown adipocyte cell line were used to explore the potential role of cold exposure and β3-adrenergic stimulation in the expression of FGF21 in BAT. Our results demonstrate that short-term exposure to cold, as well as β3-adrenergic stimulation, causes a significant induction of FGF21 mRNA levels in BAT, without a concomitant increase in FGF21 plasma levels. This finding opens new routes for the potential use of pharmaceuticals that could induce FGF21 and, hence, activate BAT thermogenesis. 相似文献
106.
107.
Background
Bacteremia by Pseudomonas aeruginosa represents one severe infection. It is not clear whether beta-lactam monotherapy leads to similar rates of treatment success compared to combinations of beta-lactams with aminoglycosides or quinolones.Methods
Retrospective cohort study from 3 tertiary hospitals (2 in Greece and 1 in Italy). Pseudomonas aeruginosa isolates were susceptible to a beta-lactam and an aminoglycoside or a quinolone. Patients received appropriate therapy for at least 48 hours. Primary outcome of interest was treatment success in patients with definitive beta-lactam combination therapy compared to monotherapy. Secondary outcomes were treatment success keeping the same empirical and definitive regimen, mortality, and toxicity.Results
Out of 92 bacteremias there were 54 evaluable episodes for the primary outcome (20 received monotherapy). Treatment success was higher with combination therapy (85%) compared to beta-lactam monotherapy (65%), however not statistically significantly [Odds ratio (OR) 3.1; 95% Confidence Interval (CI) 0.69–14.7, p = 0.1]. Very long (>2 months) hospitalisation before bacteremia was the only factor independently associated with treatment success (OR 0.73; 95% CI 0.01–0.95, p = 0.046), however this result entailed few episodes. All-cause mortality did not differ significantly between combination therapy [6/31 (19%)] and monotherapy [8/19 (42%)], p = 0.11. Only Charlson comorbidity index was associated with excess mortality (p = 0.03).Conclusion
Our study, in accordance with previous ones, indicates that the choice between monotherapy and combination therapy may not affect treatment success significantly. However, our study does not have statistical power to identify small or moderate differences. A large randomized controlled trial evaluating this issue is justified. 相似文献108.
Athanasios V. Mousiolis Panagoula Kollia Chara Skentou Ioannis E. Messinis 《Central European Journal of Biology》2011,6(6):918-924
Background
Data of syncytin 1 and 2 env gene expression in human placenta and participation in the syncytialisation phenomena has been reported. However, there are not many studies on simultaneous changes in expression of both syncytins in culture. We sought evidence on the relative expression of syncytins and syncytin 1 receptors in trophoblast cell culture treated with a differentiation inducing factor (forskolin). 相似文献109.
Background
Numerous studies have examined the effect of psychological variables on surgical recovery, but no definite conclusion has been reached yet. We sought to examine whether psychological factors influence early surgical recovery.Methods
We performed a systematic search in PubMed, Scopus and PsycINFO databases to identify studies examining the association of preoperative psychological variables or interventions with objectively measured, early surgical outcomes.Results
We identified 16 eligible studies, 15 of which reported a significant association between at least one psychological variable or intervention and an early postoperative outcome. However, most studies also reported psychological factors not influencing surgical recovery and there was significant heterogeneity across the studies. Overall, trait and state anxiety, state anger, active coping, subclinical depression, and intramarital hostility appeared to complicate recovery, while dispositional optimism, religiousness, anger control, low pain expectations, and external locus of control seemed to promote healing. Psychological interventions (guided relaxation, couple support visit, and psychiatric interview) also appeared to favor recovery. Psychological factors unrelated to surgical outcomes included loneliness, perceived social support, anger expression, and trait anger.Conclusion
Although the heterogeneity of the available evidence precludes any safe conclusions, psychological variables appear to be associated with early surgical recovery; this association could bear important implications for clinical practice. Large clinical trials and further analyses are needed to precisely evaluate the contribution of psychology in surgical recovery. 相似文献110.
Evangelou A Toliopoulos I Giotis C Metsios A Verginadis I Simos Y Havelas K Hadziaivazis G Karkabounas S 《Electromagnetic biology and medicine》2011,30(1):46-56
The main objective of our study is to investigate whether an enhancement of the immune system in end-stage cancer patients is achieved by exposure to coherent electromagnetic fields. For this reason, 15 end-stage cancer patients were exposed at low intensity, coherent electromagnetic fields at radiofrequencies ranging from 600?kHz-729?Hz, for 8?h/day, 6 days/week for 4 weeks. NKs number and cytotoxicity of NK T-lymphocytes versus K562 cancer cell line were estimated by flow cytometry, before and after exposure. Data showed that the exposure of the end-stage cancer patients to the coherent electromagnetic fields resulted in a significant increase of the number and the cytotoxicity of the NK T-lymphocytes against cancer cells, in all patients. Exposure to coherent EMFs at radiofrequencies increases the number and cytotoxicity of NK T-lymphocytes, which may contribute to the improvement of cancer patients' status. 相似文献