2.Application of Mg-PLGA-rhbFGF stent on angiogenesis in hindlimb ischemia
Hanmei BAO ; Tianjun LIU ; Feng LV
International Journal of Biomedical Engineering 2012;35(1):33-36
ObjectiveTo prepare recombinant human basic fibroblast growth factor (rhbFGF) loaded magnesium-poly(D,L-lactide-co-glycolide) (Mg-PLGA) stent and to evaluate its angiogenesis effect in rat model of hindlimb ischemia.MethodsThe stent was prepared with spiral magnesium (Mg) and loaded with therapeutic agent rhbFGF and PLGA matrix.In vitro drug release study was carried out and the effect was evaluated using a standard animal model of rat hindlimb ischemia.A mechanical drill was conducted and the stent was implanted.The concentrations of Mg2+ in the muscle adjacent to the stent,rat plasma,urine and stools of the experimental animals were tested to analyze the degradation and metabolism of metal Mg.Immunohistochemical staining was performed to evaluate the angiogenesis effect of the stent.ResultsThe drug loaded in the stent could release continuously for about 4 weeks.The concentrations of Mg2+ in the rat plasma,urine and stools were within normal range.Immunohistochemical and quantitative analysis showed that the effect of Mg-PLGA-rhbFGF stent on angiogenesis of rat limb ischemia was better than that of the control group.ConclusionRhbFGF loaded MgPLGA stent could promote angiogenesis of rat limb ischemia,and it may provide theoretical basis for the critical patients suffered from lower limb ischemic disease.
3.Preparation and characterization of dissolving microneedles with nano-enhanced mechanical properties
Yang-yang BAO ; Zhe LIU ; Yong LIU ; Feng-sen MA
Acta Pharmaceutica Sinica 2021;56(7):1999-2004
In this paper, the effects of the blend of nanoparticles and microneedle matrix materials on the mechanical properties of dissolving microneedles were studied mainly, so as to construct microneedles with excellent mechanical properties. Different kinds of nanoparticles (calcium carbonate, hydroxyapatite, silica), particle sizes (20, 60, 100 nm) and the proportion of prescription (2%, 6%, 10%) were blended with the matrix material [polyvinyl pyrrolidone (PVP), poly(1-vinylpyrrolidone-
4.Research advances of M3 receptor: a new target for treating and preventing cardiovascular disease.
Yan LIU ; Yan-jie LÜ ; Bao-feng YANG
Acta Pharmaceutica Sinica 2015;50(4):393-399
Cardiovascular disease, with high morbidity and mortality, has been threatening the health of human beings. Therefore, expecting to find a more effective therapeutic method, a plenty of researchers devote themselves to the study of the cardiovascular disease all the time. Since discovered on the heart, M3 receptor of muscarinic acetylcholine receptor (mAchR, M receptor) became a new starting point of the research of the cardiovascular disease. With more and more investigation, many people found that M3 receptor could protect the heart from kinds of cardiovascular disease, which may make it a new hopeful therapeutic point. So, expecting to give support to the reference and encouragement for the study of disease related to M3 receptor in future, this review expounds M3 receptor on the heart from the main following aspects: the effect on the heart, the influence on the cardiovascular disease and the mechanism of M3 receptor involved.
Cardiovascular Diseases
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prevention & control
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Heart
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physiology
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physiopathology
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Humans
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Receptor, Muscarinic M3
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physiology
5.Effect of core∶dentin thickness ratio on the flexure strength of IPS Empress Ⅱ heat-pressed all-ceramic restorative material
Yihong LIU ; Hailan FENG ; Yiwang BAO ; Yan QIU
Journal of Peking University(Health Sciences) 2004;0(01):-
Objective: To evaluate the effect of core∶dentin thickness ratio on the flexure strength, fracture mode and origin of bilayered IPS Empress Ⅱceramic composite specimens. Methods: IPS EmpressⅡ core ceramic, dentin porcelain and bilayered composite specimens with core∶dentin thickness ratio of 2∶1 and 1∶1 were tested in three-point flexure strength. Mean strengths and standard deviations were determined. The optical microscopy was employed for identification of the fracture mode and origin. Results: The flexure strength of dentin porcelain was the smallest (62.7 MPa), and the strength of bilayered composite specimens was smaller than single-layered core ceramic(190.2 MPa). The core∶dentin ratio did not influence the strength of bilayered composite specimens. The frequency of occurrence of bilayered specimen delaminations was higher in the group of core∶dentin thickness ratio of 1∶1 than in the group of 2∶1. Conclusion: IPS Empress Ⅱcore ceramic was significantly stronger than veneering dentin porcelain. Core∶dentin thickness ratio could significantly influence the fracture mode and origin, and bilayered IPS Empress Ⅱceramic composite specimens showed little influence in the fracture strength.
7.Surgical treatment for aortoiliac occlusive disease:prevention and management of early complications
Changwei LIU ; Bao LIU ; Wei YE ; Yuehong ZHENG ; Feng TANG ; Sheng WANG ; Heng GUAN
Chinese Journal of General Surgery 2001;0(09):-
Objective To study the treatment of a or toiliac occlusive disease and prevention and management of early complications. Methods From Mar 1998 to Mar 2005, 83 aortoiliac arterial occlusion patients were treated with embolectom y by Forgaty catheter as the main therapy for acute occlusion. In cases of chron ic occlusion percutaneous transluminal angioplasty and stenting, prosthesis graf t bypass surgery as well as proximal endovascular procedure combining with dista l arterial reconstructions were adopted on case to case basis. Results There was acute aortoiliac occlus ion in 14 cases, 6 cases (42.9%) suffered from early complications after embole ctomy, with mortality of 7.1%. In chronic aortoiliac occlusion of 69 cases,va rious complications developed in 16 cases(23.2%),of which aortoiliac arteri al stent placement in 17 cases with complications of 23.5%;prosthesis bypass in 23 cases, with complications of 30.4%, and mortality of 4.3%;aortoili ac stenting combining with femoral-popliteal bypass in 29 cases(58 legs)with complications in 5 cases(17.2%). Conclusion The expansion and development of minimally invasive tech niques along with minimal invasive surgery may reduce surgical risks,decrease m obidity and mortality rate.
8.Analysis and recognition of CD4 cell microscopic image.
Yin-feng LIU ; Bao-hua WANG ; Ping HU ; Bo CAO
Chinese Journal of Medical Instrumentation 2005;29(6):419-422
This paper introduces the technology of recognizing CD4 cell by a computer, which successfully segments the objects from the background through image processing and analyses the four features including geometric features, optical density, color and texture features. The method based on Principal Component Analysis algorithm is used for feature extraction, and a Back Propagation neural network classifier is constructed, from which the CD4 cell can be well recognized. CD4 cell, image segmentation, feature analysis, Principal Component Analysis (PCA), Back Propagation (BP) neural network classifier is constructed, from which the CD4 cell can be well recognized.
Algorithms
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CD4-Positive T-Lymphocytes
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cytology
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Image Processing, Computer-Assisted
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Microscopy
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methods
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Neural Networks (Computer)
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Principal Component Analysis
9.A review of research on the application of small intestinal submucosa in repairing osteoarticular injury.
Qi GUO ; Chun-bao LI ; Xue-zhen SHEN ; Feng QU ; Xi LU ; Yu-jie LIU
China Journal of Orthopaedics and Traumatology 2016;29(5):482-486
The ideal treatment and recovery of osteoarticular injury remain to be resolved. Small intestinal submucosa (SIS), a naturally-occurring decellularized extracellular matrix, has been recognized as an ideal scaffold for tissue engineering and widely used in repairing various tissues and organs. Nowadays its application has also been gradually increased in the field of orthopedics. We reviewed laboratorial studies and clinical trails about the application of SIS in bone and joint repair, aiming to evaluate its effects on the repair of bone, cartilage, meniscus, ligament and tendon. SIS has showed promising results in repairing bone, meniscus, ligament or tendon. However, additional studies will be required to further evaluate its effects on articular cartilage and tendon-bone healing. How to optimize SIS material,is also a focused problem concerned with making SIS a potential therapeutic option with high value for orthopedic tissue repair.
Animals
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Cell- and Tissue-Based Therapy
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Humans
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Intestinal Mucosa
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cytology
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Intestine, Small
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cytology
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Joint Diseases
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physiopathology
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surgery
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therapy
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Tissue Engineering
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instrumentation
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methods
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Tissue Scaffolds
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chemistry
10.Portable gas chromatography for determining airborne acrylonitrile in workplaces.
Jian LIU ; Feng ZHANG ; Bao-li ZHU
Chinese Journal of Industrial Hygiene and Occupational Diseases 2013;31(10):777-778
OBJECTIVETo establish a method for rapid determination of airborne acrylonitrile using a portable gas chromatograph.
METHODSA single standard sample of acrylonitrile was prepared in a laboratory and sampled by the built-in constant flow pump of the portable gas chromatograph. The sample was then preconcentrated by the preconcentrator, thermally desorbed, separated by capillary columns, and detected by a micro argon ionization detector to determine the retention time. Retention time was then used to perform qualitative analysis. Under the set condition of gas chromatography, the external standard method was used to create a standard curve for quantitative analysis of acrylonitrile.
RESULTSThe linear range of acrylonitrile on the portable gas chromatograph was 0.25 to 3.00 mg/m(3). The regression equation was y = 10(-5) x-0.0275, r = 0.9977. The limit of detection was 0.005 mg/m(3), and the lower limit of quantification was 0.25 mg/m(3). The relative standard deviation was lower than 7.09%, and the degree of accuracy was 91.09-105.54%.
CONCLUSIONPortable gas chromatography is a simple, repeatable, and accurate method for rapid determination of airborne acrylonitrile.
Acrylonitrile ; analysis ; Air Pollutants, Occupational ; analysis ; Chromatography, Gas ; instrumentation ; Workplace