Regenerating Rat Liver: Correlations Between Estrogen Receptor Localization and Deoxyribonucleic Acid Synthesis

Estrogen receptor activity was quantitated in the cytosol and nucleus of normal rat liver and in regenerating rat liver at several time intervals after 75% hepatectomy. Cytosolic estradiol binding in regenerating liver decreases at 12, 24, and 48 h after hepatectomy and at 48 h is 30% of that in normal rat liver. Nuclear estrogen binding 48 h after surgery is elevated fivefold over normal values. No alterations in affinity of the receptor for estrogen have been observed. Specificity studies indicate that the estrogen receptors from both normal and regenerating liver were similar and are highly specific for estrogens. These changes in cellular distribution of receptors parallel increases in nuclear deoxyribonucleic acid synthesis and mitotic indices in the liver. © 1984, American Gastroenterological Association. All rights reserved

Construction and Control of Genetic Regulatory Networks: A Multivariate Markov Chain Approach

In the post-genomic era, the construction and control of genetic regulatory networks using gene expression data is a hot research topic. Boolean networks (BNs) and its extension Probabilistic Boolean Networks (PBNs) have been served as an effective tool for this purpose. However, PBNs are difficult to be used in practice when the number of genes is large because of the huge computational cost. In this paper, we propose a simplified multivariate Markov model for approximating a PBN The new model can preserve the strength of PBNs, the ability to capture the inter-dependence of the genes in the network, qnd at the same time reduce the complexity of the network and therefore the computational cost. We then present an optimal control model with hard constraints for the purpose of control/intervention of a genetic regulatory network. Numerical experimental examples based on the yeast data are given to demonstrate the effectiveness of our proposed model and control policy.published_or_final_versio

Energy-efficient Walking Mechanism for Gait Rehabilitation

Human inborn walking system has been evolved well-suited to walk in a manner that conserves energy and fast to adapt to new walking conditions in an energy efficient way. Deviations from the normal walking pattern increase the extra energy expenditure of walking around 70%, comorbidity with several side-effects for gait rehabilitation. Energy efficiency is important in robot-assist gait training. We try to propose an energy efficient walking mechanism, coexisting and cooperating with patient to reconstruct the new walking system on the process of gait rehabilitation. Optimizing the assistance pattern to maximum individual performance while reducing metabolic cost, fast adapting to non-steady-state walking conditions

Solitary wave solution to Aw-Rascle viscous model of traffic flow

A traveling wave solution to the Aw-Rascle traffic flow model that includes the relaxation and diffusion terms is investigated. The model can be approximated by the well-known Kortweg-de Vries (KdV) equation. A numerical simulation is conducted by the first-order accurate Lax-Friedrichs scheme, which is known for its ability to capture the entropy solution to hyperbolic conservation laws. Periodic boundary conditions are applied to simulate a lengthy propagation, where the profile of the derived KdV solution is taken as the initial condition to observe the change of the profile. The simulation shows good agreement between the approximated KdV solution and the numerical solution.postprin

Micromagnetic simulations of current-induced magnetization switching in Co/Cu/Co nanopillars

Author name used in this publication: S. Q. Shi2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Current-induced magnetization dynamics in Co/Cu/Co nanopillars

Author name used in this publication: S. Q. Shi2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Inhibitory Effect of Polysaccharides from Scutellaria barbata D. Don on Invasion and Metastasis of 95-D Cells Lines via Regulation of C-MET and E-CAD Expressions

Purpose: To investigate the inhibitory effect of polysaccharides from Scutellaria barbata (PSB) on invasion and metastasis of lung cancer, and study the possible mechanism.Methods: PSB was extracted with water and by alcohol precipitation, and purified by DEAE-52 column chromatography. A highly invasive and metastatic lung carcinoma cell, 95-D cell line, was used for the study. Cell adhesion and invasion assays in vitro were performed to evaluate the anti-invasive and antimetastatic effects of PSB (50 - 200 μg/ml) on 95-D cell. Immunocytochemical staining and Western blot techniques were employed to study the regulatory effects of PSB on the expression of C-MET and ECAD.Results: The results indicate that PSB significantly inhibited cell invasion and migration of 95-D in a concentration-dependent manner (p < 0.05). The adhesion of 95-D cells to fibronectin was also inhibited by PSB (p < 0.05). The expression of C-MET and E-CAD in 95-D cells treated with PSB were significantly down-regulated and up-regulated, respectivelt (p < 0.05).Conclusion: Treatment with PSB can significantly inhibit the invasion and metastasis of 95-D cells in vitro, probably through the regulation of C-MET and E-CAD.Keywords: Polysaccharide, Scutellaria barbata, 95-D cell lines, Invasion, Metastasi

Studies on fermentation of synthesizing poly-β - hydroxyalkanoate(pha) by sphaerotilus sp.

2000-2001 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

An ORMOSIL-containing orthodontic acrylic resin with concomitant improvements in antimicrobial and fracture toughness properties

Global increase in patients seeking orthodontic treatment creates a demand for the use of acrylic resins in removable appliances and retainers. Orthodontic removable appliance wearers have a higher risk of oral infections that are caused by the formation of bacterial and fungal biofilms on the appliance surface. Here, we present the synthetic route for an antibacterial and antifungal organically-modified silicate (ORMOSIL) that has multiple methacryloloxy functionalities attached to a siloxane backbone (quaternary ammonium methacryloxy silicate, or QAMS). By dissolving the water-insoluble, rubbery ORMOSIL in methyl methacrylate, QAMS may be copolymerized with polymethyl methacrylate, and covalently incorporated in the pressure-processed acrylic resin. The latter demonstrated a predominantly contact-killing effect on Streptococcus mutans ATCC 36558 and Actinomyces naselundii ATCC 12104 biofilms, while inhibiting adhesion of Candida albicans ATCC 90028 on the acrylic surface. Apart from its favorable antimicrobial activities, QAMS-containing acrylic resins exhibited decreased water wettability and improved toughness, without adversely affecting the flexural strength and modulus, water sorption and solubility, when compared with QAMS-free acrylic resin. The covalently bound, antimicrobial orthodontic acrylic resin with improved toughness represents advancement over other experimental antimicrobial acrylic resin formulations, in its potential to simultaneously prevent oral infections during appliance wear, and improve the fracture resistance of those appliances.published_or_final_versio