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61.
Introduction: We investigated the effect of age on the complexity of muscle activity and the variance in the force of isometric contraction. Methods: Surface electromyography (sEMG) from biceps brachii muscle and force of contraction were recorded from 96 subjects (20–70 years of age) during isometric contractions. Results: There was a reduction in the complexity of sEMG associated with aging. The relationship of age and complexity was approximated using a bilinear fit, with the average knee point at 45 years. There was an age‐associated increase in the coefficient of variation (CoV) of the force of muscle contraction, and this increase was correlated with the decrease in complexity of sEMG (r2 = 0.76). Conclusions: There was an age‐associated increase in CoV and also a reduction in the complexity of sEMG. The correlation between these 2 factors can be explained based on the age‐associated increase in motor unit density. Muscle Nerve 47: 545–549, 2013 相似文献
62.
A series of indolyl oxoacetamide analogs was synthesized, characterized, and evaluated for their pancreatic lipase inhibitory activity using porcine pancreatic lipase (type II) and 4-nitrophenyl butyrate. Compound 8d exhibited a potent inhibition, with an IC50 value of 4.53 µM, followed by 8c (IC50 = 5.12 µM), compared with the standard drug, orlistat (IC50 = 0.99 µM). Furthermore, analogs 8c and 8d exhibited a reversible competitive inhibition, similar to orlistat. Molecular docking studies of the compounds 7a–f and 8a – f were in agreement with the in vitro results, wherein 8d exhibited a potential MolDock score of −163.052 kcal/mol. A 10-ns molecular dynamics simulation of 8d complexed with pancreatic lipase confirmed the role of π–π stacking and π–cation interactions with the lid domain and Arg 256, respectively, in stabilizing the ligand at the active site (maximum observed root mean square deviation ≈ 2 Å). The present study led to the identification of novel indolyl oxoacetamides ( 8a – d ) as potential pancreatic lipase inhibitory leads that might further result in enhanced potency through lead optimization. 相似文献
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Hermer-Vazquez R Hermer-Vazquez L Srinivasan S Chapin JK 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,180(2):217-235
A major question in neuroscience concerns how widely separated brain regions coordinate their activity to produce unitary
cognitive states or motor actions. To investigate this question, we employed multisite, multielectrode recording in rats to
study how olfactory and motor circuits are coupled prior to the execution of an olfactory-driven, GO/NO-GO variant of a skilled,
rapidly executed (∼350–600 ms) reaching task. During task performance, we recorded multi-single units and local field potentials
(LFPs) simultaneously from the rats’ olfactory cortex (specifically, the posterior piriform cortex) and from cortical and
subcortical motor sites (the caudal forepaw M1, and the magnocellular red nucleus, respectively). Analyses on multi-single
units across areas revealed an increase in beta-frequency spiking (12–30 Hz) during a ∼100 ms window surrounding the Final Sniff of the GO cue before lifting the arm (the “Sniff-GO window”) that was seldom seen when animals sniffed the NO-GO cue. Also
during the Sniff-GO window, LFPs displayed a striking increase in beta, low-gamma, and high-gamma energy (12–30, 30–50, and
50–100 Hz, respectively), and oscillations in the high gamma band appeared to be coherent across the recorded sites. These
results indicate that transient, multispectral coherence across cortical and subcortical brain sites is part of the coordination
process prior to sensory-guided movement initiation.
Raymond Hermer-Vazquez, Linda Hermer-Vazquez these two authors contributed equally. 相似文献
65.
Mandal R Kutala VK Khan M Mohan IK Varadharaj S Sridhar A Carnes CA Kálai T Hideg K Kuppusamy P 《The Journal of pharmacology and experimental therapeutics》2007,323(1):119-127
Any clinical intervention (e.g., coronary angioplasty, thrombolysis) used to reintroduce blood flow to an ischemic region of the myocardium is accompanied by a complex enzymatic cascade of reactions resulting in severe injury to the heart, termed myocardial ischemia/reperfusion (I/R) injury. In this study, we evaluated the ability of H-3010 (1-hydroxy-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrole-3-carboxylic acid (2-(3,4-dimethoxyphenyl)-5-([2-(3,4-dimethoxyphenyl)ethyl]-methylamino)-2-isopropylpentyl)-amide), a pyrroline modification of verapamil (2-(3,4-dimethoxyphenyl)-5-[2-(3,4-dimethoxyphenyl)ethylmethyl-amino]-2-(1-methylethyl)pentanenitrile), to protect the heart against I/R-mediated injury. Isolated perfused rat hearts pretreated with verapamil and H-3010 were subjected to 30 min of global no-flow ischemia followed by 45 min of reperfusion. The recovery (expressed as a percentage of preischemic baseline) in contractile function (left ventricular developed pressure) of hearts subjected to I/R was significantly higher in hearts treated with H-3010 at 5 microM (51.0 +/- 6.4%) as well as at 50 microM (75.1 +/- 7.4%) as compared with verapamil at 5 microM (32.2 +/- 3.7%) or untreated control hearts (18.1 +/- 2.8%). Creatine kinase release was significantly attenuated in hearts treated with H-3010 (45.7 +/- 4.5 U/liter) as compared with untreated controls (131.5 +/- 6.4 U/liter). Similar trends were also observed for lactate dehydrogenase release as well. A marked reduction in percent area of infarction was observed in the H-3010 group (11.7 +/- 1.6%) compared with verapamil (25.1 +/- 2.9%) and control (41.3 +/- 1.9%) groups. Additional in vitro studies showed a marked decrease in reactive oxygen species generation with H-3010. In conclusion, our data clearly demonstrated that the verapamil derivative, H-3010, significantly decreased I/R-induced cardiac dysfunction. This can be attributed to the combined benefits of the pyrroline moiety (antioxidant) and the parent verapamil component (antiarrhythmic) in the protection of the heart from I/R-induced injury. 相似文献
66.
Hitendra Ahooja Sridhar Prasad Kaushal Gautam Bikram Ghimire 《Indian journal of ophthalmology》2020,68(12):3050
A 23-year-old male presented to us wanting spectacle removal for cosmetic purposes. He underwent bilateral wavefront optimized (WFO) laser-assisted in situ keratomileusis (LASIK) on the Alcon Wavelight® EX-500 excimer laser with an incorrectly treated astigmatism axis for left eye due to a manual data entry error in the laser. WFO LASIK treats the sphere and cylinder only. LASIK enhancement with topographic-guided ablation resulted in the elimination of all refractive errors and gave excellent results. Wavelight® topographic-guided treatment can perform two separate layers of correction in the same ablation: The first is to treat the corneal irregularities for the higher order aberration (HOA) removal, the second one meant to treat the sphere and cylinder if indicated. 相似文献
67.
Sridhar Madabhushi Narsaiah Chinthala Abhinav Kanwal Gagandeep Kaur Sanjay K. Banerjee 《Medicinal chemistry research》2014,23(4):2062-2069
2-(4-((1-Alkyl/aryl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)naphtho[1,2-d] were prepared and evaluated as protein tyrosine phosphatase 1B (PTP1B) inhibitors. In this study, two new compounds with potent PTP1B inhibitory activity were identified. 相似文献
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