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41.
Isoform-specific regulation of 5' AMP-activated protein kinase in skeletal muscle from obese Zucker (fa/fa) rats in response to contraction 总被引:5,自引:0,他引:5
Glucose transport can be activated in skeletal muscle in response to insulin via activation of phosphoinositide (PI) 3-kinase and in response to contractions or hypoxia, presumably via activation of 5' AMP-activated protein kinase (AMPK). We determined the effects of insulin and muscle contraction/hypoxia on PI 3-kinase, AMPK, and glucose transport activity in epitrochlearis skeletal muscle from insulin-resistant Zucker (fa/ fa) rats. Insulin-stimulated glucose transport in isolated skeletal muscle was reduced 47% in obese versus lean rats, with a parallel 42% reduction in tyrosine-associated PI 3-kinase activity. Contraction and hypoxia elicited normal responses for glucose transport in skeletal muscle from insulin-resistant obese rats. Isoform-specific AMPK activity was measured in skeletal muscle in response to insulin, contraction, or hypoxia. Contraction increased AMPKalpha1 activity 2.3-fold in lean rats, whereas no effect was noted in obese rats. Hypoxia increased AMPKalpha1 activity to a similar extent (more than sixfold) in lean and obese rats. Regardless of genotype, contraction, and hypoxia, each increased AMPKalpha2 activity more than fivefold, whereas insulin did not alter either AMPKalpha1 or -alpha2 activity in skeletal muscle. In conclusion, obesity-related insulin resistance is associated with an isoform-specific impairment in AMPKalpha1 in response to contraction. However, this impairment does not appear to affect contraction-stimulated glucose transport. Activation of AMPKalpha2 in response to muscle contraction/ exercise is associated with a parallel and normal increase in glucose transport in insulin-resistant skeletal muscle. 相似文献
42.
Sheelu Varghese Hui Xu David Bartlett Marybeth Hughes James F. Pingpank Tatiana Beresnev H. Richard Alexander 《Annals of surgical oncology》2010,17(7):1870-1877
Background
Patients with ocular melanoma liver metastases have a poor prognosis, treatment options are limited, and median survival is less than 1 year. In this study, we characterized the early molecular changes that occur in tumors immediately after vascular isolation perfusion with melphalan with hyperthermia in patients with hepatic metastases from ocular melanoma. 相似文献43.
Stephanie Molden Danielle Patterson Megan Tarr Tatiana Sanses Jessica Bracken Aimee Nguyen Heide S. Harvie Amanda White Sarah A. Hammil Miles Murphy Rebecca G. Rogers 《International urogynecology journal》2010,21(10):1253-1259
Introduction and hypothesis
To determine risk factors for sling revision after midurethral sling (MUS) placement.Methods
This multicenter case-control study included patients who underwent MUS placement and subsequent revision secondary to voiding dysfunction from January 1999–2007 from nine Urogynecology centers across the USA. Direct logistic regression analysis was used to determine which diagnostic variables predicted sling revision.Results
Of the patients, 197 met the study criteria. Patient demographics, urodynamic findings, and operative differences did not increase the risk for sling revision. Risk factors for sling revision did include: pre-existing voiding symptoms (OR 2.76, 95% CI 1.32–5.79; p?=?0.004) retropubic sling type (OR?=?2.28, 95% CI 1.08–4.78; p?=?0.04) and concurrent surgery (OR?=?4.88, 95% CI 2.16–11.05; p?<?0.001)Conclusions
This study determined that pre-existing obstructive voiding symptoms, retropubic sling type, and concurrent surgery at the time of sling placement are risk factors for sling revision. 相似文献44.
45.
Aleksei Viktorovich Novik Svetlana Anatolievna Protsenko Irina Alexandrovna Baldueva Lev Michailovich Berstein Vladimir Nikolaevich Anisimov Irina Nikolaevna Zhuk Anna Igorevna Semenova Dilorom Khamidovna Latipova Elena Viktorovna Tkachenko Tatiana Yurievna Semiglazova 《The oncologist》2021,26(5):364-e734
Lessons Learned
- Melatonin did not increase the efficacy of systemic chemotherapy in melanoma.
- Metformin did not increase the efficacy of systemic chemotherapy in melanoma.
46.
47.
Mularek-Kubzdela T Grajek S Olasińska A Seniuk W Grygier M Trojnarska O Lesiak M Cieśliński A 《International journal of cardiology》2008,127(3):433-435
Patients with exercise angina >2 months (n:13) showed significantly lower SigmaST elevation during 120 s balloon coronary occlusion than those with =<2 months (n:7), or those with angina at rest <=2 days (n:8) but similar to patients with angina at rest >2 days (n:7). These results underscore the importance of the kind and duration of angina in limiting the extent of ischemia during coronary occlusion. 相似文献
48.
49.
Tatiana Raskovalova Patrick B. Deegan Pramod K. Mistry Elena Pavlova Ruby Yang Ari Zimran Juliette Berger Celine Bourgne Bruno Pereira Jose Labarere Marc G. Berger 《Haematologica》2021,106(2):437
Chitotriosidase activity and CCL18 concentration are interchangeably used for monitoring Gaucher disease (GD) activity, together with clinical assessment. However, comparative studies of these two biomarkers are scarce and of limited sample size. The aim of this systematic review with meta-analysis of individual participant data (IPD) was to compare the accuracy of chitotriosidase activity and CCL18 concentration for assessing type I GD severity. We identified cross-sectional and prospective cohort studies by searching Medline, EMBASE, and CENTRAL from January 1995 to June 2017, and by contacting research groups. The primary outcome was a composite of liver volume >1.25 multiple of normal (MN), spleen volume >5 MN, hemoglobin concentration <11 g/dL, and platelet count <100x109/L. Overall, IPD included 1,109 observations from 334 patients enrolled in nine primary studies, after excluding 111 patients with undocumented values and 18 patients with deficient chitotriosidase activity. IPD were unavailable for 14 eligible primary studies. The primary outcome was associated with a 5.3-fold (95% Confidence Interval [CI]: 4.2-6.6) and 3.0-fold (95% CI: 2.6-3.6) increase of the geometric mean for chitotriosidase activity and CCL18 concentration, respectively. The corresponding areas under the receiver operating characteristics curves were 0.82 and 0.84 (summary difference, 0.02, 95% CI: -0.02 to 0.05). The addition of chitotriosidase activity did not improve the accuracy of the CCL18 concentration. Estimates remained robust in the sensitivity analysis and consistent across subgroups. Neither the chitotriosidase activity nor the CCL18 concentration varied significantly according to a recent history of bone events among 97 patients. In conclusion, the CCL18 concentration is as accurate as chitotriosidase activity in assessing hematological and visceral parameters of GD severity and can be measured in all GD patients. This meta-analysis supports the use of CCL18 rather than chitotriosidase activity for monito-ring GD activity in routine practice. 相似文献