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Rest Period (rest + period)
Selected AbstractsAcute exercise reverses TRB3 expression in the skeletal muscle and ameliorates whole body insulin sensitivity in diabetic miceACTA PHYSIOLOGICA, Issue 1 2010A. Matos Abstract Aim:, TRB3 became of major interest in diabetes research when it was shown to interact with and inhibit the activity of Akt. Conversely, physical exercise has been linked to improved glucose homeostasis. Thus, the current study was designed to investigate the effects of acute exercise on TRB3 expression and whole body insulin sensitivity in obese diabetic mice. Methods:, Male leptin-deficient (ob/ob) mice swam for two 3-h-long bouts, separated by a 45-min rest period. After the second bout of exercise, food was withdrawn 6 h before antibody analysis. Eight hours after the exercise protocol, the mice were submitted to an insulin tolerance test (ITT). Gastrocnemius muscle samples were evaluated for insulin receptor (IR) and IRS-1 tyrosine phosphorylation, Akt serine phosphorylation, TRB3/Akt association and membrane GLUT4 expression. Results:, Western blot analysis showed that TRB3 expression was reduced in the gastrocnemius of leptin-deficient (ob/ob) mice submitted to exercise when compared with respective ob/ob mice at rest. In parallel, there was an increase in the insulin-signalling pathway in skeletal muscle from leptin-deficient mice after exercise. Furthermore, the GLUT4 membrane expression was increased in the muscle after the exercise protocol. Finally, a single session of exercise improved the glucose disappearance (KITT) rate in ob/ob mice. Conclusion:, Our results demonstrate that acute exercise reverses TRB3 expression and insulin signalling restoration in muscle. Thus, these results provide new insights into the mechanism by which physical activity ameliorates whole body insulin sensitivity in type 2 diabetes. [source] Elevated expression of bisecting N -acetylglucosaminyltransferase-III gene in a human fetal hepatocyte cell line by hepatitis B virusJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2004JAE-KYOUNG SHIM Abstract Background and Aim:, UDP-N-acetylglucosamine: ,-D-mannoside ,-1,4 N-acetylglucosaminyltransferase III (GnT-III) is a key enzyme in N-glycan biosytnesis. Human GnT-III enzyme activity was found to be elevated in the serum of patients with hepatomas and liver cirrhosis and in hepatocellular carcinoma tissues. Therefore, to understand the relationship between the elevation in GnT-III activity and hepatitis B viral (HBV) hepartocarcinogenesis, we investigated GnT-III gene expression in the HBV-infected cells. Methods:, A cell line, HFH-T1, producing HBV was produced by natural infection of human fetal hepatocytes. A 170-bp band corresponding to the pre-S1 region of HBV was detected in the culture medium by polymerase chain reaction. Virions were also isolated from the culture medium by sucrose density gradient centrifugation. The synthesis of both ,-fetoprotein and albumin as an indicator that these cells were functional hepatocytes and the extent of differentiation was examined. Polymerase chain reaction and Western blot analysis using a monoclonal antibody, GT273, which was prepared using human aglycosyl recombinant GnT-III were used for HBV DNA and GnT-III detection. Results:, Two types of HBV-related particles were secreted into the culture medium; one was a Dane particle (40 nm in size) containing HBV DNA and the other was a subviral hepatitis B surface antigen particle (20 nm in size) that did not contain the viral genome. The secretion from the cell line was diminished by the number of passages and, thus, this cell was renamed as HFH-T2. A decreased level of the HBV was secreted from the cells after a rest period. HFH-T2 cells showed a weak staining for ,-fetoprotein and a moderate staining for albumin in the cytoplasm around the nucleus. High levels of a 0.7 kb DNA fragment originating from GnT-III DNA were detected in HFH-T2 cells. Western blot analysis using a monoclonal antibody, GT273, whixh was prepared using human aglycosyl recombinant GnT-III showed a single band, corresponding to Mr 63 kDa, whereas aglycosyl GnT-III showed a band at Mr 53 kDa, with a molecular weight difference of about 10 kDa. This indicates that HFH-T2 cells express glycosylated GnT-III. GnT-III activities were 347.2 ± 53.6 pmol/mg of protein/h in HFH-T2, 276 ± 26.3 in Hep3B, 252.5 ± 23.3 in HepG2 and 30.7 ± 3.4 in NIH-3T3. GnT-III activity was higher in HFH-T2 cells than in the hepatoma cell lines, Hep3B and HepG2. Conclusion:, A human fetal hepatocyte cell line was transformed by infection with HBV and the cell line expressed high levels of GnT-III as the levels of secretion of HBV decreased. The decrease in HBV secretion from HFH-T2 cells could be due to a high level of expression of GnT-III. Such a cell line could be used to investigate relationships between HBV infection and glycosyltransferase gene expression. Furthermore, this cell line will be useful in future studies on the effect of the expression of GnT-III on other glycosyltransferase. [source] Fast four-dimensional coronary MR angiography with k-t GRAPPAJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2008Peng Lai MS Abstract Purpose To investigate the effectiveness of k-t GRAPPA for accelerating four-dimensional (4D) coronary MRA in comparison with GRAPPA and the feasibility of combining variable density undersampling with conventional k-t GRAPPA (k-t2 GRAPPA) to alleviate the overhead of acquiring autocalibration signals. Materials and Methods The right coronary artery of nine healthy volunteers was scanned at 1.5 Tesla. The 4D k -space datasets were fully acquired and subsequently undersampled to simulate partially parallel acquisitions, namely, GRAPPA, k-t GRAPPA, and k-t2 GRAPPA. Comparisons were made between the images reconstructed from full k-space datasets and those reconstructed from undersampled k-space datasets. Results k-t GRAPPA significantly reduced artifacts compared with GRAPPA and high acceleration factors were achieved with only minimal sacrifices in vessel depiction. k-t2 GRAPPA could further increase imaging speed without significant losses in image quality. Conclusion By exploiting high-degree spatiotemporal correlations during the rest period of a cardiac cycle, k-t GRAPPA and k-t2 GRAPPA can greatly increase data acquisition efficiency and, therefore, are promising solutions for fast 4D coronary MRA. J. Magn. Reson. Imaging 2008. © 2008 Wiley-Liss, Inc. [source] Coronary MR angiography at 3T during diastole and systoleJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2007Ahmed M. Gharib MD Abstract Purpose To investigate the impact of end-systolic imaging on quality of right coronary magnetic resonance angiography (MRA) in comparison to diastolic and to study the effect of RR interval variability on image quality. Materials and Methods The right coronary artery (RCA) of 10 normal volunteers was imaged at 3T using parallel imaging (sensitivity encoding [SENSE]). Navigator-gated three-dimensional (3D) gradient echo was used three times: 1) end-systolic short acquisition (SS): 35-msec window; 2) diastolic short (DS): middiastolic acquisition using 35-msec window; and 3) diastolic long (DL): 75-msec diastolic acquisition window. Vectorcardiogram (VCG) data was used to analyze RR variability. Vessel sharpness, length, and diameter were compared to each other and correlated with RR variability. Blinded qualitative image scores of the images were compared. Results Quantitative and qualitative parameters were not significantly different and showed no significant correlation with RR variability. Conclusion Imaging the RCA at 3T during the end-systolic rest period using SENSE is possible without significant detrimental effect on image quality. Breaking away from the standard of imaging only during diastole can potentially improve image quality in tachycardic patients or used for simultaneous imaging during both periods in a single scan. J. Magn. Reson. Imaging 2007;26:921,926. © 2007 Wiley-Liss, Inc. [source] Prospective blinded comparison of surface versus wire electromyographic analysis of muscle recruitment in shoulder instabilityPHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 1 2009Anju Jaggi Abstract Background.,This pilot study assesses level of agreement between surface and fine-wire electromyography (EMG), in order to establish if surface is as reliable as fine wire in the diagnosis and treatment of abnormal muscle patterning in the shoulder.,Method.,Eighteen participants (11 female) with unstable shoulders were recruited after written consent and ethical approval. Anthropometric information and mean skinfold size for triceps, subscapular, biceps and suprailiac sites were obtained. Triple-stud self-adhesive surface electrodes ('Triode'; Thermo Scientific, Physio Med Services, Glossop, Derbyshire, England) were placed over pectoralis major (PM), latissimus dorsi (LD), anterior deltoid (AD) and infraspinatus (IS) at standardized locations. Participants performed five identical uniplanar standard movements (flexion, abduction, external rotation, extension and cross-body adduction). After a 20-minute rest period, a dual-needle technique for fine-wire insertion was performed and the standard movements were repeated. An experienced examiner in each technique reported if muscle activation patterns differed from agreed normal during any movement and were blinded to the other test results. Sensitivity, specificity and Kappa values for level of agreement between methods were calculated for each muscle according to the method of Altman (1991).,Results.,Fifteen participants were successfully tested. Sensitivity, specificity and Kappa values between techniques for each muscle were PM (57%, 50%, 0.07), LD (38%, 85%, 0.22), AD (0%, 76%, ,0.19) and IS (85%, 75%, 0.6). Only IS demonstrated high sensitivity and specificity and a moderate level of agreement between the two techniques. There was no correlation between skinfold size and agreement levels.,Conclusion.,The use of surface EMG may help to classify types of shoulder instability and recognize abnormal muscle patterns. It may allow physiotherapists to direct specific rehabilitation strategies, avoiding strengthening of inappropriate muscles. It has a reasonable degree of confidence to evaluate IS but may have poor sensitivity in detecting abnormal patterns in PM, LD and AD. Further work is required to see if investigator interpretation may have been a factor for the poor level of agreement. Copyright © 2008 John Wiley & Sons, Ltd. [source] Acute exercise modulates the Foxo1/PGC-1, pathway in the liver of diet-induced obesity ratsTHE JOURNAL OF PHYSIOLOGY, Issue 9 2009Eduardo R. Ropelle PGC-1, expression is a tissue-specific regulatory feature that is extremely relevant to diabetes. Several studies have shown that PGC-1, activity is atypically activated in the liver of diabetic rodents and contributes to hepatic glucose production. PGC-1, and Foxo1 can physically interact with one another and represent an important signal transduction pathway that governs the synthesis of glucose in the liver. However, the effect of physical activity on PGC-1,/Foxo1 association is unknown. Here we investigate the expression of PGC-1, and the association of PGC-1,/Foxo1 in the liver of diet-induced obese rats after acute exercise. Wistar rats swam for two 3 h-long bouts, separated by a 45 min rest period. Eight hours after the acute exercise protocol, the rats were submitted to an insulin tolerance test (ITT) and biochemical and molecular analysis. Results demonstrate that acute exercise improved insulin signalling, increasing insulin-stimulated Akt and Foxo1 phosphorylation and decreasing PGC-1, expression and PGC-1,/Foxo1 interaction in the liver of diet-induced obesity rats under fasting conditions. These phenomena are accompanied by a reduction in the expression of gluconeogenesis genes, such as phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphate (G6Pase). Thus, these results provide new insights into the mechanism by which exercise could improve fasting hyperglycaemia. [source] Acute physical exercise reverses S -nitrosation of the insulin receptor, insulin receptor substrate 1 and protein kinase B/Akt in diet-induced obese Wistar ratsTHE JOURNAL OF PHYSIOLOGY, Issue 2 2008José R. Pauli Early evidence demonstrates that exogenous nitric oxide (NO) and the NO produced by inducible nitric oxide synthase (iNOS) can induce insulin resistance. Here, we investigated whether this insulin resistance, mediated by S -nitrosation of proteins involved in early steps of the insulin signal transduction pathway, could be reversed by acute physical exercise. Rats on a high-fat diet were subjected to swimming for two 3 h-long bouts, separated by a 45 min rest period. Two or 16 h after the exercise protocol the rats were killed and proteins from the insulin signalling pathway were analysed by immunoprecipitation and immunoblotting. We demonstrated that a high-fat diet led to an increase in the iNOS protein level and S -nitrosation of insulin receptor , (IR,), insulin receptor substrate 1 (IRS1) and Akt. Interestingly, an acute bout of exercise reduced iNOS expression and S -nitrosation of proteins involved in the early steps of insulin action, and improved insulin sensitivity in diet-induced obesity rats. Furthermore, administration of GSNO (NO donor) prevents this improvement in insulin action and the use of an inhibitor of iNOS (l- N6 -(1-iminoethyl)lysine; l -NIL) simulates the effects of exercise on insulin action, insulin signalling and S -nitrosation of IR,, IRS1 and Akt. In summary, a single bout of exercise reverses insulin sensitivity in diet-induced obese rats by improving the insulin signalling pathway, in parallel with a decrease in iNOS expression and in the S -nitrosation of IR/IRS1/Akt. The decrease in iNOS protein expression in the muscle of diet-induced obese rats after an acute bout of exercise was accompanied by an increase in AMP-activated protein kinase (AMPK) activity. These results provide new insights into the mechanism by which exercise restores insulin sensitivity. [source] Plasma lysozyme levels in sheatfish Silurus glanis (L.) subjected to stress and experimental infection with Edwardsiella tardaAQUACULTURE RESEARCH, Issue 12 2002D Caruso Abstract Two experiments were conducted to assess plasma lysozyme levels, leucocrit and haematocrit in juvenile sheatfish (90,140 g) under experimentally induced stress and infection. Stress was provoked by random modification of environmental light for 15 min, 16 times a day with a halogen lamp (500 W) and by holding fish in a net for 3 min twice a day. In the first trial, repeated measuring of marked sheatfish showed a progressive significant decrease in plasma lysozyme level, a significant increase in leucocrit and a significant decrease in haematocrit. After a rest period of 1 week, only the leucocrit value was back to the prestress value. In the second trial, light-induced stress did not lead to any variation in lysozyme, leucocrit or haematocrit values. However, after intraperitoneal injection of Edwardsiella tarda (7 × 108 cfu), a strong increase in plasmatic lysozyme in both stressed and unstressed groups of sheatfish was observed. The increase was significant vs. prechallenge levels 3 and 6 days after contamination, but no significant difference was detected between stressed and unstressed fish, despite the strongest stress (light+handling stress) applied to the fish at the beginning of contamination. Decreases in haematocrit values were observed in both groups of fish. A clear increase in leucocrit appeared in unstressed fish, whereas stressed fish showed a significant decrease in leucocrit values. Condition factor was significantly decreased by all kinds of stress. There were no difference in mortality between stressed and unstressed groups. [source] Procedures Can Be Learned on the Web: A Randomized Study of Ultrasound-guided Vascular Access TrainingACADEMIC EMERGENCY MEDICINE, Issue 10 2008Jordan Chenkin MD Abstract Objectives:, Web-based learning has several potential advantages over lectures, such as anytime,anywhere access, rich multimedia, and nonlinear navigation. While known to be an effective method for learning facts, few studies have examined the effectiveness of Web-based formats for learning procedural skills. The authors sought to determine whether a Web-based tutorial is at least as effective as a didactic lecture for learning ultrasound-guided vascular access (UGVA). Methods:, Participating staff emergency physicians (EPs) and junior emergency medicine (EM) residents with no UGVA experience completed a precourse test and were randomized to either a Web-based or a didactic group. The Web-based group was instructed to use an online tutorial and the didactic group attended a lecture. Participants then practiced on simulators and live models without any further instruction. Following a rest period, participants completed a four-station objective structured clinical examination (OSCE), a written examination, and a postcourse questionnaire. Examination results were compared using a noninferiority data analysis with a 10% margin of difference. Results:, Twenty-one residents and EPs participated in the study. There were no significant differences in mean OSCE scores (absolute difference = ,2.8%; 95% confidence interval [CI] = ,9.3% to 3.8%) or written test scores (absolute difference = ,1.4%; 95% CI = ,7.8% to 5.0%) between the Web group and the didactic group. Both groups demonstrated similar improvements in written test scores (26.1% vs. 25.8%; p = 0.95). Ninety-one percent (10/11) of the Web group and 80% (8/10) of the didactic group participants found the teaching format to be effective (p = 0.59). Conclusions:, Our Web-based tutorial was at least as effective as a traditional didactic lecture for teaching the knowledge and skills essential for UGVA. Participants expressed high satisfaction with this teaching technology. Web-based teaching may be a useful alternative to didactic teaching for learning procedural skills. [source] Rising cortisol at childcare: Relations with nap, rest, and temperamentDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2002Sarah E. Watamura Abstract An unexpected rise in cortisol across the day in full-day, center-based childcare has been recently observed. Most of the children in these studies exhibited the rise across the day at childcare, but the expected drop at home. Possible explanations include more or less napping at childcare than at home. This study measured cortisol during childcare at 10:30 a.m., pre-rest, post-rest, and 3:30 p.m. for 35 children, and at 10:30 a.m. and 3:30 p.m. at home for 8 children. Duration and quality of rest were coded during nap periods. For 91% of children, cortisol rose at childcare and for 75% dropped at home. None of the napping variables were related to the rise at childcare nor were differences found between home and childcare rest. Factors other than daytime rest periods seem likely to account for the rise in cortisol across the childcare day, possibly factors involving the interactional demands of group settings during this developmental period. © 2002 John Wiley & Sons, Inc. Dev Psychobiol 40: 33,42, 2002 [source] Companion planting , behaviour of the cabbage root fly on host plants and non-host plantsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2005Kate Morley Abstract Six-hundred individual female cabbage root flies (Delia radicum L.) (Diptera: Anthomyiidae) were each observed for 20 min under laboratory conditions to record how they behaved after landing on a host or a non-host plant. Fly movements were recorded on host plants [cabbage ,Brassica oleracea var. capitata (Cruciferae)] and non-host plants [clover ,Trifolium subterraneum L. (Papilionaceae)] surrounded by bare soil and on cabbage surrounded by clover. The most frequently observed behaviours made by the flies were (1) hops/spiral flights and (2) walks/runs. In the bare soil situation, the 50 individual flies observed in each treatment made 66 hops/spiral flights on the cabbage and 94 on the clover. When the two plants were tested together the movements were not additive as, instead of the expected 160 hops/spiral flights in the mixed plant treatment, the flies made 210 hops/spiral flights when they landed initially on cabbage but only 130 when they landed initially on clover. Few of the flies that landed initially on clover moved onto the host plant, even though the host plant was only a few centimetres away. The duration of the individual walks and runs made by the cabbage root flies were similar on both the host and non-host plants. The only differences were the numbers of walks/runs made and the time the flies remained inactive. On the host plants, the females made four walks/runs, each of about 12 s duration, interspersed by rest periods that totalled 1.5 min. In contrast, on the non-host plants the females made 10 walks/runs, each of about 9 s duration, interspersed by rest periods that totalled 7 min. Therefore, after landing on a plant, the flies, on average, left the host plant after 2.25 min and the non-host plant after 8.5 min. Our conclusion is that the protracted time spent on the non-host plants is the mechanism that disrupts insects from finding host plants in diverse plantings. Hence, the flies were arrested by non-host plants rather than being repelled or deterred as suggested in earlier studies. [source] Radio-tracking gravel particles in a large braided river in New Zealand: a field test of the stochastic theory of bed load transport proposed by EinsteinHYDROLOGICAL PROCESSES, Issue 3 2001H. M. Habersack Abstract Hans A. Einstein initiated a probabilistic approach to modelling sediment transport in rivers. His formulae were based on theory and were stimulated by laboratory investigations. The theory assumes that bed load movement occurs in individual steps of rolling, sliding or saltation and rest periods. So far very few attempts have been made to measure stochastic elements in nature. For the first time this paper presents results of radio-tracing the travel path of individual particles in a large braided gravel bed river: the Waimakariri River of New Zealand. As proposed by Einstein, it was found that rest periods can be modelled by an exponential distribution, but particle step lengths are better represented by a gamma distribution. Einstein assumed an average travel distance of 100 grain-diameters for any bed load particle between consecutive points of deposition, but larger values of 6·7 m or 150 grain-diameters and 6·1 m or 120 grain-diameters were measured for two test particle sizes. Together with other available large scale field data, a dependence of the mean step length on particle diameter relative to the D50 of the bed surface was found. During small floods the time used for movement represents only 2·7% of the total time from erosion to deposition. The increase in percentage of time being used for transport means that it then has to be regarded in stochastic transport models. Tracing the flow path of bed load particles between erosion and deposition sites is a step towards explaining the interactions between sediment transport and river morphology. Copyright © 2001 John Wiley & Sons, Ltd. [source] Psoriasis induced by topical imiquimodAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 1 2004Jason K Wu SUMMARY We report the provocation of localized psoriasis at the sites of application of topical imiquimod, possibly evolving into a generalized flare. A patient with pre-existing psoriasis that had been stable for 14 years was treated with imiquimod 5% cream daily for 6 weeks to three superficial basal cell carcinomas. During treatment one of the lesions developed severe local skin reactions necessitating rest periods, and received only 18 applications in 6 weeks. The other two lesions were treated for all 42 days. Psoriasiform changes developed at all three application sites. Nine-and-a-half weeks after completing treatment the patient developed disseminated small psoriatic lesions. Other recognized triggers of psoriasis were not identified. The psoriasis resolved slowly with conventional treatment. [source] | |||||||||||||