Research, development and application of collagen: a review / 生物工程学报

Collagen, which widely exists in skin, bone, muscle and other tissues, is a major structural protein in mammalian extracellular matrix. It participates in cell proliferation, differentiation, migration and signal transmission, plays an important role in tissue support and repair and exerts a protective effect. Collagen is widely used in tissue engineering, clinical medicine, food industry, packaging materials, cosmetics and medical beauty due to its good biological characteristics. This paper reviews the biological characteristics of collagen and its application in bioengineering research and development in recent years. Finally, we prospect the future application of collagen as a biomimetic material.

Stem cell therapy for Alzheimer's disease and related disorders: current status and future perspectives

Underlying cognitive declines in Alzheimer's disease (AD) are the result of neuron and neuronal process losses due to a wide range of factors. To date, all efforts to develop therapies that target specific AD-related pathways have failed in late-stage human trials. As a result, an emerging consensus in the field is that treatment of AD patients with currently available drug candidates might come too late, likely as a result of significant neuronal loss in the brain. In this regard, cell-replacement therapies, such as human embryonic stem cell- or induced pluripotent stem cell-derived neural cells, hold potential for treating AD patients. With the advent of stem cell technologies and the ability to transform these cells into different types of central nervous system neurons and glial cells, some success in stem cell therapy has been reported in animal models of AD. However, many more steps remain before stem cell therapies will be clinically feasible for AD and related disorders in humans. In this review, we will discuss current research advances in AD pathogenesis and stem cell technologies; additionally, the potential challenges and strategies for using cell-based therapies for AD and related disorders will be discussed.

Effects of ethane 1,2-dimethanesulfonate preconditioning on renal ische-mia/reperfusion injury in male rats / 中国病理生理杂志

AIM:To investigate the effects of ethane 1,2-dimethanesulfonate (EDS) preconditioning on renal ischemia/reperfusion (I/R) injury in male Sprague-Dawley (SD) rats.METHODS: Male SD rats (n=48) were ran-domly assigned to 6 groups:blank, sham, I/R, EDS+I/R, EDS+testosterone (TST) +I/R, and castration (Cast)+I/R.The renal pedicles were bilaterally occluded with a microvascular clamp for 45 min to establish renal I/R-induced in-jury model.Bilateral orchiectomy was conducted 2 weeks before surgery .EDS (75 mg/kg) was intraperitoneally injected 5 d before operation .Blood samples were collected 24 h after reperfusion from the vena orbitalis posterior plexus .Luteinizing hormone (LH), TST, serum creatinine (SCr), blood urea nitrogen (BUN), and kidney injury molecule-1 (KIM-1) were detected.The renal tissues were harvested to measure the level of TNF-αand the expression of Fas mRNA and caspase-3 protein.RESULTS:Serum TST levels in EDS +I/R group and Cast +I/R group were below the minimum detectable threshold.Compared with other groups , the rats in EDS+I/R group and Cast +I/R group had higher levels of SCr , BUN and KIM-1 (P0.05), but KIM-1 level in EDS+I/R group was lower than that in Cast +I/R group (P<0.05).After reper-fusion for 24 h, the levels of TST and LH in EDS +I/R group, Cast+I/R group and EDS+TST+I/R group were lower than those 1 h before operation (P<0.05).Compared with Cast+I/R and I/R group, the TNF-αlevel and expression of Fas mRNA and caspase-3 protein were significantly decreased in EDS +I/R group ( P<0.05 ) .CONCLUSION: EDS preconditioning substantially reduces the serum TST level , thus attenuating I/R-induced acute renal injury .TNF-α-induced Fas/FasL pathway may be involved in this process .

Current situation of scientific research capacity of schistosomiasis control in-stitutions of municipal cities in Hubei Province / 中国血吸虫病防治杂志

Objective To evaluate the levels of the Chinese literature published by the schistosomiasis control institutions of 17 municipal cities of Hubei Province. Methods The related literature published from 2008 to 2012 was searched from the da-tabases of CNKI VIP and Wanfang and then screened by the exclusion criteria. NoteExpress and Excellsoftwares were applied to collect the literature and carry out the bibliometric analysis. Results A total of 168 papers were included and the schistosomia-sis control institutes of Jingzhou City and Wuhan City had the highest amount. The literature was mainly published in Chinese Journal of Schistosomiasis Control and Journal of Public Health and Preventive Medicine. The comprehensive influence index-es of the schistosomiasis control institutes of Jingzhou Wuhan and Qianjiang cities were higher. The schistosomiasis control in-stitutes of Jingzhou City had an extensive content of literature while Wuhan was mainly focused on epidemiology case report and Oncomelania hupensis snail control. Conclusion The research of schistosomiasis in each municipal city has an extensive con-tent and the research capacity of the schistosomiasis control institute of Jingzhou City is relatively outstanding.

Pharmacokinetics of a fusion protein for human acidic fibroblast growth factor and transcriptional activator protein in rat and its penetration across blood-brain barrier / 药学学报

This paper is to report the study of the pharmacokinetics of a fusion protein TAT-haFGF(14-154) for human acidic fibroblast growth factor and transcriptional activator protein in rat plasma, and the investigation of their penetration across blood-brain barrier in mice and rats, in order to provide a basis for clinical development and treatment of Alzheimer's disease. Enzyme-linked immunosorbent assay (ELISA) was used to determine concentration of TAT-haFGF(14-154) in rat plasma and in mouse brain homogenate; and immunohistochemistry was used to analyze the distribution in brain. The concentration-time curve fitted two-compartment open model which was linear kinetics elimination after a single intravenous injection of TAT-haFGF(14-154) in rat at the dose of 300 microg x kg(-1). The half life time was 0.049 +/- 0.03 h for distribution phase and 0.55 +/- 0.05 h for elimination phase, and the weight was 1/C2. The result showed that TAT-haFGF(14-154) could be detected in the brain by ELISA and immunohistochemistry, the elimination of TAT-haFGF(14-154) in rat was swift, and TAT-haFGF(14-154) could penetrate across the blood-brain barrier, distribute in pallium and hippocampus and locate in the nucleus.

Preparation and in vitro/in vivo pharmacological studies of bFGF/collagen composite sponge / 中国药科大学学报

Aim: To investigate a new type wound dressing,basic fibroblast growth factor(bFGF)/collagen com-posite sponge,and conduct its pharmacological studies in vitro and in vivo.Methods: bFGF/collagen composite sponge was prepared using fresh pig skin and bFGF.The sponge's physicochemical properties were studied.MTT assay was used to detect the proliferation effect of the sponge extract on 3T3 cells.Delayed allergy of the sponge was tested for the assurance of its biosafety.Results: Results showed that the physicochemical properties of bFGF/collagen composite sponge with high and low doses of bFGF have no significant difference from those of blank collagen sponge.SDS-page analysis indicated that the composite sponge has apparent strip in 18 kD.It was also found that bFGF/collagen composite sponge was responsible for significant effects on 3T3 cell proliferation in comparison to saline treatement(P <0.01,P <0.05).In the allergy study,during the periods of the induction and stimulation,no allergic reaction was found in bFGF/collagen composite sponge groups with high and low doses of bFGF,while severe reactions and inflammation occurred in positive group(2,4-dinitrochlorobenzene).Furthermore,pathological examination indicated the intact dermal structure and no sign of inflammation.Conclu-sion: The developed sponge has good physicochemical propertis and noticed cellular proliferation without dermal irritation.There is much potential to develop bFGF/collagen composite sponge into a new kind of wound dressing material for clinical use.

Study of preparation and biocompatibility of acidic fibroblast growth factor/collagen composite sponge / 生物医学工程学杂志

A new type wound dressing-aFGF/collagen composite sponge was prepared by bovine tendon and aFGF. Its physical function, biocompatibility, and hemocompatibility in particular, were studied for full assurance of its biosafety. The acute toxicity and skin irritation tests of composite sponge of high and low doses were negative. Recalcification test demonstrated that the recalcification time of composite sponge was much longer than that of the control group. Hemolysis test revealed that the composite sponge did not lead to hemolysis. Platelet adhesion test showed that the surface of composite sponge had less platelet adhesion than did the surface of glass, and the composite sponge did not destroy platelets. The results indicate that aFGF/collagen composite sponge has good biocompatibility and possibility for clinical use.

Effect of basic fibroblast growth factor plus Brucea Javanica oil emulsion on repairing back skin wound of rabbits / 中国组织工程研究

BACKGROUND: It has been proved that the application of basic fibroblast growth factor (bFGF) combined with Brucea Javanica oil emulsion can accelerate wound healing and inhibit scar formation.OBJECTIVE: To observe the effects of bFGF plus Brucea Javanica oil emulsion cream on accelerating the skin wound healing of rabbits.DESIGN: A randomized controlled observation.SETTING: Center of Biotechnological Research and Development, Jinan University; College of Pharmacy, Jinan University.MATERIALS:The experiment was carried out in the College of Pharmacy, Jinan University from June to September in 2004. Eight Beijing big-ear white rabbits (4 males and 4 females) of 2.0-2.5 kg were provided by the experimental animal center of Southern Medical University (certification number: SoKx-2002-010). bFGF sterile freeze dried powder agent,provided by Guangzhou Changsheng Gene Pharmaceutical Co.,Ltd (batch number: 20040219; specific activity was 6 000 U/bottle), was prepared to solution with water for injection before application. Brucea Javanica oil emulsion (manufactured by Zhejiang 999 Bang'erkang Pharmaceutical Co.,Ltd.) was provided by Professor Yao from staff Room of Pharmacy, Shenyang Pharmaceutical University.METHODS: The rabbits were anesthetized and disinfected, 5 round wounds with diameter of 1.8 cm and area of 2.54 cm2were induced from front to back by bilateral incision at 1.5 cm from middle spine of rabbit. The 5 wounds of each rabbit were randomly divided into bFGF-treated group (90 U/cm2), bFGF+Brucea Javanica oil emulsion group [the wound was smeared with Brucea Javanica oil emulsion (30 mg/cm2) 30 minutes after bFGF (90 U/cm2)], Brucea Javanica oil emulsion treated group [the wound was smeared with Brucea Javanica oil emulsion (30 mg/cm2)], blank emulsion group (30 mg/cm2) and blank control group (the wound was smeared with saline). The medication was give immediately after injury, and changed once a day for 16 days. At 4, 8, 12 and 16 days after injury, the wound areas were recorded with the method of hyaline membrane tracing (the wound was covered with clean saran wrap, the size of wound was traced,and then sheared to be weighed, and converted to calculate the area), and the volume of wounded cavity was measured by infusing water. At 8 and 16 days, the wound tissue was removed, stained after routine tissue sections, and the conditions of growth of granulation tissue and reepithelization on the wound surface were observed.MAIN OUTCOME MEASURE: The wound area, volume of wounded cavity, and the conditions of growth of granulation tissue and reepithelization on the wound surface were obviously at different time points after injury in each group.RESULTS:All the 8 rabbits were involved in the analysis of results. ① Wound areas at different time points in each group: The wound areas in the bFGF+Brucea Javanica oil emulsion group at 4, 8 and 12 days after medication were smaller than those in the blank control group at corresponding time points [(2.05±0.35), (1.59±0.25), (0.55±0.25) cm2;(2.53±0.30), (2.41±0.19), (1.09±0.34) cm2, P＜0.05-0.01]. The wound areas in the bFGF group at 8 and 12 days after medication were (1.71±0.31) and (0.51±0.10) cm2, which were significantly smaller than those in the blank control group at corresponding time points (P＜0.05-0.01). ② Volume of the wounded cavity in each group: The wound volume in the bFGF group at 4 days after injury was markedly smaller than that in the blank control group at corresponding time point [(0.49±0.12), (0.59±0.1) mL, P＜0.05]. The wound volumes in the bFGF+Brucea Javanica oil emulsion group at 4 and 8days after injury were significantly smaller than those in the blank control group at corresponding time points [(0.47±0.12), (0.30±0.08) mL; (0.59±0.1), (0.41±0.07) mL, P＜0.05, 0.01]. ③ Growth of granulation tissue and reepithelization on the wound surface in each group: At 8 days after injury, the inflammatory reaction was milder and fibroblasts proliferated significantly in the bFGF+Brucea Javanica oil emulsion group, and the numbers of capillary plumules and fibroblasts were significantly more than those in the blank control group. The conditions in the blank control group and blank emulsion group were generally the same that there were severe inflammatory reactions, obvious increase of granulation tissue, fewer new capillaries, and unobvious proliferation of epidermic cells. At 16 days after injury, the contraction and reepithelization on the wound surface were obvious, and the new epithelia went towards the wound center rapidly in the bFGF+Brucea Javanica oil emulsion group.CONCLUSION : The application of Brucea Javanica oil emulsion plus bFGF can obviously accelerate the repair of incised wound on the back of rabbits.

Effect of lansoprazole on gastric ulceration in rats / 中国病理生理杂志

AIM:To investigate the effect of lansoprazole on gastric ulceration in rats. METHODS:Using the gastric ulcer model induced by hemorrhagic shock, restraint water-immersion stress and pylorus-ligature, the protective effect of lansoprazole (iv) on gastric ulceration was observed. RESULTS: Pretreatment with lansoprazole (7.5-60 mg/kg) significantly inhibited the formation of gastric ulcer in the three models in a dose-dependent manner. The autiulcer efficacy of lansoprazole was similar to that of omeprazole in the equal dose, but stronger than that of omeprazole for ulcer induced by water-immersion stress. CONCLUSION: The intravenously administered lansoprazole inhibited formation of experimental gastric ulcer in rats.