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find Keyword "regulation" 42 results
  • THE TRANSCRIPTION FACTOR LIVER ACTIVATOR PROTEIN TRANSACTIVATES α1(I) COLLAGEN GENE IN ACTIVATED HEPATIC STELLATE CELLS

    Objective To elucidate the role of the transcription factor liver activator protein (LAP, a member of the C/EBP family) in the expression of α1(I) collagen gene in activated hepatic stellate cells (HSCs). Methods Rat HSCs were prepared from SD rats by in situ perfusion and singlestep density Nycodenz gradient. Two chimeric luciferase reporter gene plasmids containing the human collagen α1(I) gene promoter fragments (-804~+1 452 or -804~+222) were constructed. Culture-activated HSCs were co-transfected with the reporter gene contructs and mammalian vector expressing LAP using the cationic-liposome mediated method, and the promoter activity was determined by measuring luciferase activity. Results The luciferase reporter gene construct containing the first intron of α1(I) collagen gene (-804~+1 452, was called as PGL3-col) had a higher level of gene expression, as compared with the construct lacking the first intron 〔was called as PGL3-col (△intron)-in activated HSCs (315±45 U/mg protein vs 220±70 U/mg protein, P<0.05). Transient transfection of the vector expressing LAP significantly increased basal transcription from PGL3-col and PGL3-col (△intron) reporter gene vectors (587±62 U/mg protein vs 315±45 U/mg protein and 326±52 U/mg protein vs 220±70 U/mg protein respectively, both P<0.05). Conclusion The transcription factor LAP transactivates collagen α1(I) gene in activated HSCs, and the first intron is important for α1(I) collagen gene transcription activity in activated HSCs.

    Release date:2016-09-08 01:59 Export PDF Favorites Scan
  • Research progress on the treatment of limb motor dysfunction after stroke based on brain-limb coordinate regulation

    Limb motor dysfunction is the most common sequela of stroke. Its recovery cycle is long and difficult, which has an important impact on the physiology and psychology of patients. Therefore, the recovery of limb motor function after stroke has become the focus and difficulty of current rehabilitation. Brain-limb coordinate regulation technology is a rehabilitation strategy that effectively promotes the recovery of limb motor function and brain function through the organic combination of rehabilitation technology with limbs as target organs and brain as target organs. Based on the brain-limb coordinate regulation technology, this paper will systematically elaborate its theory and application through literature review, and then provide a more reasonable and effective choice for the treatment of limb motor dysfunction in stroke patients.

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  • Regulatory role of long non-coding RNA in peripheral nerve injury and neural regeneration

    ObjectiveTo summarize the regulatory role of long non-coding RNA (lncRNA) in peripheral nerve injury (PNI) and neural regeneration.MethodsThe characteristics and mechanisms of lncRNA were summarized and its regulatory role in PNI and neural regeneration were elaborated by referring to relevant domestic and foreign literature in recent years.ResultsNeuropathic pain and denervated muscle atrophy are common complications of PNI, affecting patients’ quality of life. Numerous lncRNAs are upregulated after PNI, which promote the progress of neuropathic pain by regulating nerve excitability and neuroinflammation. Several lncRNAs are found to promote the progress of denervated muscle atrophy. Importantly, peripheral nerve regeneration occurs after PNI. LncRNAs promote peripheral nerve regeneration through promoting neuronal axonal outgrowth and the proliferation and migration of Schwann cells.ConclusionAt present, the research on lncRNA regulating PNI and neural regeneration is still in its infancy. The specific mechanism remains to be further explored. How to achieve clinical translation of experimental results is also a major challenge for future research.

    Release date:2021-08-30 02:26 Export PDF Favorites Scan
  • Construction of Beta 2 AdrenergicReceptor Down-RegulativeAsthmatic Model

    Objective To establish a beta 2 adrenergic receptor ( β2 R) down-regulative asthmatic model, to explore the mechanism of β2 R down-regulation and effectiveness of corticosteroids. Methods Thirty-two BALB/c mice were divided into four groups, ie. a control group, an asthmatic group, a β2R downregulative group, and a dexamethasone group. The asthmatic group, the β2 R down-regulative group and the dexamethasone group were sensitized on 0th, 14th and 21th day by intraperitoneal injection of ovalbumin ( OVA) together with aluminumhydroxide in a total volume of 200 μL. Fromthe 28th day on, the mice were challenged with an aerosol of 1% OVA( W/V) in saline using an ultrasonic nebulizer 30 min/d for a week.The β2 R down-regulative group and the dexamethasone group underwent the same procedure as the asthmatic group besides daily intraperitoneal injection of 60 μg salbutamol and inhaling an aerosol of 0. 01%salbutamol 30 min/d for a week half an hour before challenged with OVA. The dexamethasone group was injected dexamethasone 5 mg·kg- 1·d - 1 for a week by intraperitoneal injection on the basis of OVA challenge and salbutamol intervention. The control group was sensitized and challenged with PBS. Airway resistance was measured by plethysmography. IL-4 and IFN-γlevels in BALF, and total IgE concentration in serum were measured by ELISA. Total and differential cell counts in bronchial alveolar lavage fluid ( BALF)were measured. Total amount and number of β2 R in lung tissue were evaluated by immune blotting analysis and radioligand receptor binding assay, respectively. Results Compared to the control group and the dexamethasone group, airway resistance of the asthmatic group and the β2 R down-regulative group increasedobviously provocated by a high dose of acetylcholine ( P lt;0. 01) . Eosinophil, neutrophil, lymphocyte counts in BALF, IL-4 level in BALF, and total IgE in serumincreased significantly also ( P lt;0. 01) , while IFN-γin BALF decreased significantly. Compared to the control group, the asthmatic group and the dexamethasonegroup, the total amount and number of β2 R significantly decreased in the β2 R down-regulative group ( P lt;0. 01) , while no significant difference was found among the control group, the asthmatic group and the dexamethasone group. Conclusions β2 R down-regulative asthmatic model can be successfully establishedby peritoneal injection and inhalation of salbutamol on the basis of OVA sensitization and challenge.Dexamethasone can prevent the down-regulation of β2 R.

    Release date:2016-08-30 11:53 Export PDF Favorites Scan
  • Immunoregulatory Effects of ω-3 Polyunsaturated Fatty Acid and Its Applications in Organ Transplantation

    Objective To investigate the immunoregulatory effects of immunonutrient ω-3 polyunsaturated fatty acid (PUFA) and its applications in organ transplantation. Methods Relevant literatures of recent years were reviewed. Results The immunoregulatory effects of ω-3 PUFA can inhibit proliferation and activation of the immunocompetent cells including T cell and B cell, reduce cytokine production, modulate immunologic response, improve graft function, pro-long survival, reduce episodes of rejection, and lessen adverse reactions of immunosuppressor.Conclusion  ω-3 PUFA should have wide applications in organ transplantation due to its immunoregulatory effects. However, this research should be further studied.

    Release date:2016-09-08 11:49 Export PDF Favorites Scan
  • Advances in surface modification of orthopedic titanium implants for anti-infection

    Titanium and its alloys have become one of the most widely used implant materials in orthopedics because of their excellent mechanical properties and biocompatibility. Implant-associated infection is the main reason of failure of orthopedic implant surgery. The anti-infection modification of implant surface has received more attention in the field of infection prevention and developed rapidly. This article focuses on the current research status of simple anti-infection surface modifications that make titanium implants possess anti-adhesion, bactericidal activity or antibacterial membrane activity, as well as the research progress of composite functional surface modifications that promote bone integration, osteogenesis or immunomodulatory effects on the basis of anti-infection, so as to provide references for the construction of orthopedic implants with composite functions.

    Release date:2023-10-24 03:04 Export PDF Favorites Scan
  • Molecular Regulation of Skeletal Satellite Cell's Self-renewal

    Skeletal muscle possesses a remarkable ability for its regeneration and injured tissue repair. This ability depends on the activity and contributions of muscle satellite cells. Proliferating satellite cells, termed myogenic precursor cells or myoblasts, are activated and driven out of their quiescent state upon muscle injury. In this summary, we present a review to summarize the molecular regulation in skeletal satellite cells to light on the satellite cells' self-renewal mechanism.

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  • State regulation for complex biological networks based on dynamic optimization algorithms

    Recent studies showed that certain drugs can change regulatory reaction parameters in gene regulatory networks (GRNs) and therefore restore pathological cells to a normal state. A state control framework for regulating biological networks has been built based on attractors and bifurcation theory to analyze this phenomenon. However, the control signal is self-developed in this framework, of which the parameter perturbation method can only calculate the state transition time of cells with single control variable. Therefore, an optimal control method based on the dynamic optimization algorithms is proposed for complex biological networks modeled by nonlinear ordinary differential equations (ODEs). In this approach, dynamic optimization problems are constructed based on basic characteristics of the biological networks. Furthermore, using an example of a simple low-dimensional three-node GRN and a complex high-dimensional cancer GRN, MATLAB is utilized to calculate optimal control strategies with either single or multiple control variables. This method aims to achieve accurate and rapid state regulation for biological networks, which can provide a reference for experimental researches and medical treatment.

    Release date:2020-04-18 10:01 Export PDF Favorites Scan
  • Electroencephalogram characteristics under successful cognitive reappraisal in emotion regulation

    Cognitive reappraisal is an important strategy for emotion regulation. Studies show that even healthy people may not be able to implement this strategy successfully, but the underlying neural mechanism behind the behavioral observation of success or failure of reappraisal is unclear. In this paper, 28 healthy college students participated in an experiment of emotional regulation with the cognitive reappraisal strategy. They were asked to complete the cognitive psychological questionnaires before the experiment. Their behavioral scores and scalp electroencephalogram (EEG) signals were collected simultaneously during the experiment. We divided all the subjects into two groups, according to the statistical test of valence scores. Then we analyzed their questionnaires, early event-related potential (ERP) components N200, P200, and late positive potential (LPP), and calculated the correlation between the valence score and the amplitude of LPP. The results showed that, in both groups, compared with negative-watching, the reappraisal induced larger N200 and P200 components and there were two modulation patterns (“increase” and “decrease”) of the reappraisal effect on the amplitude of early LPP (300−1 000 ms after stimulus onset). Moreover, correlation analysis showed that significant positive correlation between two differences in the successful group, i.e., the greater difference in the valence scoresin between reappraisal and negative-watching, the greater difference in the amplitude of early LPP between reappraisal and negative-watching; but no such effect was found in the failure group. These results indicated that, whether reappraisal was successful or not, no significant effect on early ERP components was found; and there were different patterns of the reappraisal effect on early LPP. The difference between successful and failure groups was mainly reflected in early LPP, that is, the EEG characteristics and behavioral scores of successful group were significantly positively correlated. Furthermore, the small sample analysis showed that this correlation only existed in the pattern of "increase". In the future, more research of this modulation mode is necessary in order to find more stable EEG characteristics under successful cognitive reappraisal in emotion regulation.

    Release date:2020-10-20 05:56 Export PDF Favorites Scan
  • The inverse stochastic resonance in a small-world neuronal network under electromagnetic stimulation

    Electromagnetic stimulation is an important neuromodulation technique that modulates the electrical activity of neurons and affects cortical excitability for the purpose of modulating the nervous system. The phenomenon of inverse stochastic resonance is a response mechanism of the biological nervous system to external signals and plays an important role in the signal processing of the nervous system. In this paper, a small-world neural network with electrical synaptic connections was constructed, and the inverse stochastic resonance of the small-world neural network under electromagnetic stimulation was investigated by analyzing the dynamics of the neural network. The results showed that: the Levy channel noise under electromagnetic stimulation could cause the occurrence of inverse stochastic resonance in small-world neural networks; the characteristic index and location parameter of the noise had significant effects on the intensity and duration of the inverse stochastic resonance in neural networks; the larger the probability of randomly adding edges and the number of nearest neighbor nodes in small-world networks, the more favorable the anti-stochastic resonance was; by adjusting the electromagnetic stimulation parameters, a dual regulation of the inverse stochastic resonance of the neural network can be achieved. The results of this study provide some theoretical support for exploring the regulation mechanism of electromagnetic nerve stimulation technology and the signal processing mechanism of nervous system.

    Release date:2023-10-20 04:48 Export PDF Favorites Scan
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