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Zhao Q.,China Rehabilitation Research Center
Journal of Computational and Theoretical Nanoscience | Year: 2012

The partition function is a fundamental concept of equilibrium thermodynamics. It encodes the particle distribution at different energy levels within a thermal system. By modifying the partition function of a particle, the partition function of a protein conformational state has been obtained. According to the protein thermodynamic structure theory, a protein conformational state represents one thermal system within a protein. The partition function of it encodes the thermodynamic relation among the different conformational states of a protein. Many experimental observations and models in enzymology, biochemistry, and molecular biology have been summarized and reexamined by applying this concept. This paper discusses the following: (1) the partition function of a protein conformational state; (2) the conformation distribution between the two states; (3) the protein conformation distribution along the temperature gradient and the protein conformation stability curve; (4) the agonist efficiency and conformational distribution of a receptor along voltage; (5) the enzyme active conformation distribution along the temperature gradient; (6) the enzyme active conformation distribution with respect to protein flexibility; (7) a revision of the Arrhenius equation for enzymatic reactions; and (8) the biophysical nature of conformational equilibrium and deformation. Copyright © 2012 American Scientific Publishers All rights reserved.

Jia C.,Capital Medical University | Liao L.-M.,Capital Medical University | Chen G.,Capital Medical University | Sui Y.,China Rehabilitation Research Center
Spinal Cord | Year: 2013

Study design:The study was designed as a single-arm clinical trial.Objectives:To investigate the effect of detrusor botulinum toxin A (BoNTA) injection on urinary tract infection (UTI) in patients with spinal cord injury (SCI).Setting:The study was performed in a national rehabilitation research center of China.Methods:Between September 2010 and May 2012, 41 male inpatients with neurogenic detrusor overactivity (NDO) caused by traumatic SCI, mean age 36.0±8.8 years, duration of SCI since inclusion 21.5±17.3 months, received an injection of 300 U BoNTA into detrusor. Before and 3 months after injection, each patient kept a bladder diary, underwent video-urodynamic investigation and urine culture. All UTIs occurring in the 6 months before and the 6 months after injection were recorded.Results:Before injection, the mean number of UTI over 6 months was 1.39±1.36. After injection, the mean significantly decreased to 0.78±0.96 (P=0.023). The mean maximum detrusor pressure during filling decreased significantly in the patients of detrusor overactivity (n=24) compared with patients of normo-active detrusor (n=17) after injection (35.4±12.2 vs 20.9±7.9 cmH 2 O, P=0.000), meantime, the decrease of UTI was significant in the former (1.29±1.21 vs 0.41±0.62 cmH 2 O, P=0.015) while no significant in the latter (1.46±1.47 vs 1.04±1.08, P=0.319).Conclusion:Detrusor BoNTA injection significantly decreased UTI in SCI patients with NDO. This effect seems to be related to the decrease of detrusor pressure. © 2013 International Spinal Cord Society All rights reserved.

Tu W.-J.,Capital Medical University | Dong X.,Dalian Medical University | Zhao S.-J.,China Rehabilitation Research Center | Yang D.-G.,Capital Medical University | Chen H.,Institute of Rehabilitation Science of China
Journal of Neuroendocrinology | Year: 2013

Inflammation and activation of the neuroendocrine systems comprise important aspects of stroke pathophysiology. The present study investigated whether baseline plasma brain natriuretic peptide (BNP), N-terminal pro-brain natriuretic peptide (NT-proBNP), cortisol and copeptin levels on admission can predict short-term outcomes and mortality after acute ischaemic stroke. The study group consisted of 189 patients who had their first acute ischaemic stroke. Plasma levels of BNP, NT-proBNP, cortisol and copeptin were evaluated to determine their value with respect to predicting functional outcome and mortality within 3 months. As a result of cardiovascular and neurological investigations (including imaging techniques), lesion size, stroke subtype classification and clinical outcome after 3 months were determined. Plasma levels of BNP, NT-proBNP, cortisol and copeptin were associated with stroke severity, as well as short-term functional outcomes. After adjusting for all other significant outcome predictors, NT-proBNP, cortisol and copeptin remained as independent outcome predictors. In the receiver operating characteristic curve analysis, the biomarker panel (including BNP, NT-proBNP, cortisol and copeptin) predicted functional outcome and death within 90 days significantly more efficiently than the National Institute of Health Stroke Scale (NIHSS) or the biomarker alone. Copeptin showed a significantly greater discriminatory ability as a single biomarker compared to BNP, NT-proBNP, cortisol and NIHSS score. These results suggest that a biomarker panel may add valuable and time-sensitive prognostic information in the early evaluation of acute ischaemic stroke. This may provide a channel for interventional therapy in acute stroke. © 2013 British Society for Neuroendocrinology.

Chen L.-H.,Capital Medical University | Chen L.,Capital Medical University | Liu L.-X.,China Rehabilitation Research Center
Clinical Neurology and Neurosurgery | Year: 2011

Objectives: The aim of this study was to evaluate visual outcome in patients with tuberculum sellae meningioma (TSM) treated microsurgically using the frontolateral or fronto-orbital approach and optic canal unroofing to resect tumor involvement of the optic canal. Methods: Data from 67 patients with TSMs who underwent microsurgical treatment by a frontolateral approach (n = 44) or fronto-orbital approach (n = 23) between January 2002 and December 2008 were retrospectively collected and analyzed. Change in visual function was evaluated as the main outcome. Results: Total tumor resection was achieved in 62 of 67 cases (92.4%). Postoperative, visual acuity was improved in 87 eyes (64.9%) and unchanged in 39 eyes (29.1%), and the optic nerve was therefore preserved in 126 of 134 eyes (94.0%). Visual field deficits were improved or stable in 65 eyes, no patient experienced worsening of vision in both eyes. There was no mortality in our series. Conclusions: The frontolateral approach with microsurgical dissection of the Sylvian fissure provides quick access to TSMs, which can be resected safely and totally. Visual function is improved and neurological and ophthalmological morbidity is minimal. Optic nerve decompression by intradural clinoidectomy and optic canal unroofing is likely to increase the rate of reducing or eliminating preoperative visual symptoms. © 2010 Elsevier B.V. All rights reserved.

Qin L.,Purdue University | Wang Y.,McGill University | Tao L.,China Rehabilitation Research Center | Wang Z.,Chinese Academy of Sciences
Journal of Biochemistry | Year: 2011

As a member of receptor tyrosine kinase (RTK) family, insulin-like growth factor-1 (IGF1) receptor (IGF1R) activates several downstream pathways to transmit proliferative signals from extracellular stimulation. AKT as a major effector plays a pivotal role in integrating various survival signalling cascades. Our data here show that hyperactive AKT leads to the decrease of IGF1R at the transcriptional level, which could be partly restored by phosphatidylinositol-3 kinase (PI3K) inhibitors including wortmannin and LY294002. Moreover, the decrease of IGF1R impairs the sensitivity of IRS1 to the stimulation by IGF1. mTOR as a main downstream target of AKT is not involved in the AKT-mediated down-regulation of IGF1R. © The Authors 2011.

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