AIM: A new type of unsaturated poly (ester-amide) viz maleic anhydride-phthalic anhydride-propylene glycol-neopentylene glycol-hexane diamine copolymer was prepared by melt polycondensation and characterized.METHODS: To use it as biodegradable bone fixation polymer materials, the flexural strength of unsaturated poly (ester-amide) prepared under different heat treatment conditions was measured after depth cross-linking. The degradation and hydrolysis of the polymer were investigated in phosphate buffer (0.1 mol/L, pH7.4) at 37 ℃ and in 0.1 mol/L NaOH standard solution at room temperature.RESULTS: The results obtained indicate that increasing heat treatment time or temperature can dramatically increase the flexural strength of cross-linked unsaturated poly (ester-amide). The maximum flexural strength of the cross-linked polymer containing 50 wt% of cross-linker was 123 MPa. After degradation 3 months, the flexural strength of the cross-linked polymer that contained 50 wt% of cross-linker and was heated at 195 ℃ for 18 hours could maintain as high as 114.3 MPa.Heat treatment conditions and cross-linker content play an important role to control the mass loss of the cross-linked polymer during the hydrolysis. The polymer exhibits bulk erosion property.CONCLUSION: The preliminary results obtained suggested that the copolymer might be used as bone internal fixation material.

Objective To introduce a kind of UPS for portable type-B ultrasonic in vehicular-charging at the situation of flowing in battle field. Methods Long time power supply for type-B ultrasonic and other related medical devices was realized through AC/DC alteration switch. Conclusion It functioned well in field test. Conclusion Being light and convenient with AC/DC, it is worth popularizing.

Objective To investigate the effect of a novel isoflavone compound(F11) on the plasma lipid and cholesterol of the ovarectomied rat.Methods Female SD rats at age of 3 months old were randomly divided into 6 groups,that is,sham operation group(Sham),normal saline group(2 ml/d),estradiol group(E2,50 ?g?kg-1?d-1),and 3 F11 groups(15,50,150 mg?kg-1?d-1).Besides the Sham group,the ovary of the rats from other groups were resected,and received the injection as above mentioned.All rats were killed 10 weeks later,and their plasma lipid,total cholesterol,LDL,HDL,and body weight and uterine weight were measured.Results The plasma lipid,total cholesterol,LDL,HDL were significantly different in normal saline group and 4 treatment group(P

Platelet-derived growth factors (PDGFs) are a member of family of glycoprotein dimers (Mr 27000～35000) that exert potent mitogenic and chemotactic activities toward cells of mesenchymal origin. The PDGFs possess a myriad of critical roles in embryonic development,cellular differentiation and response to tissue damage. It is one of the growth factors,which appear early during the process of wound healing. Especially,PDGFs can effectively promote the healing of some chronic refractory wounds,such as diabetes mellitus ulcer,chronic venous ulcer,bedsore,radioactivity ulcer,etc..

Amniotic membrane is composed of amniotic epithelium, basement-membrane and stroma. Amniotic membrane is an easily obtained biomaterial and easily to be also processed, preserved and transported. However, its applicability will not be destroyed after it has been preserved for a long time(about one year). Thus it has been utilized widely in laboratory and clinical surgery. Generally, homologous amniotic membrane does not induce rejection after allotransplantation, and it is a bio-absorbable and degradable material. The purpose of this paper is to review the characteristics of amniotic membrane that makes it potentially useful in promoting tissue repair.
Amnion ; transplantation ; Biological Dressings ; Humans ; Tissue Engineering

Objective To explore the effect of long-term depleted uranium (DU)ingestion on testosterone production in rats, and its involvement mechanism. Methods Male and female rats (F0 and F1 respectively) for 160 days, respectively. The contents of testosterone (T), luteinizing hormone (LH), and follicle stimulating hormone (FSH) in serum were detected in 20 months of F0 generations, and 15 months of F1 generations. RT-PCR was used to analyze the levels of StAR mRNA and P450scc mRNA. Results Compared with the normal control group, the testosterone contents in exposed F0 and F1 generations increased, the lowest was 51.73 U/L, but those of LH and FSH decreased. The expression of StAR mRNA in the low-doze group of F1 generation (StAR/β-actin = 1.35) was up-regulated, down-regulated for other groups.compared with the normal control group (P450scc/β-actin = 0. 313), the expression of P450scc mRNA in the low- and high-dose groups of F0 generation were decreased (P450scc/β-actin = 0.21), and those in the low- and high-dose groups of F1generation were increased (P450scc/β-actin = 0.623) (P ≤ 0.01). Conclusion Long-term DU exposure inhibit the male reproduction by intervening the sexual hormone production through down-regulated the expression of StAR mRNA and P450scc roRNA.

Objective　To observe some biological features of bone marrow mesenchymal stem cells and explore the best conditions for isolatin g and culturing in vitro. Methods　Common cell culture techn ique, light and electron microscopy were used to study the effects of the growth , proliferation, morphology of the bone marrow mesenchymal stem cells in differe nt adherent time, concentration of serum and cell density. Results　The best culture condition in vitro for growth was 4-24 hours adherent time, 5%-10% fetal bovine serum, (4-8)×104/ml cell density. The cells were sp indle in shape and had a strong ability of proliferation. The time for cell duplication was 3 to 4 days. The cells showed the characteristics of stem cell s in electron microscope. Conclusion　The best condition for iso lation and culture of bone marrow mesemchymal stem cells was successfully establ ished and some biological features were obserred. It found a base for further in vestigation and using of mesenchymal stem cells.

Objective To clone platelet-derived growth factor A chain (PDGF-A) gene and insert PDGF-A gene into. Enhanced green fluorescent protein (EGFP) vector and then transformed into dermis-drived mesenchymal stem cells (DMSCs). Methods cDNA clones encoding human PDGF-A gene were isolated from a human hepatoma cell line mRNA by reverse transcription-polymerase chain reaction (RT-PCR). The PCR amplified fragment of PDGF-A gene was cloned into pMD18-T vector. The eukaryotic expression vector pEGFP-N1/PDGF-A was constructed by subcolone PDGF-A gene into pEGFP-N1 vector. PDGF-A gene was transfected into DMSCs with the help of Fugene 6 transfection reagent. Results Full cDNA sequence encoding human PDGF-A gene had been cloned, which sequence was consistent with the reported sequence in GenBank by sequence assaying. Conclusion cDNA sequence encoding human PDGF-A gene was successfully cloned into pEGFP-N1. The transient expression of PDGF-A gene in DMSCs has been realized.

To retrospectively analyze the safety and efficacy of low dose subcutaneous decitabine regimen in patients with acute myeloid leukemia (AML) and intermediate-or higer-risk myelodysplastic syndrome (MDS).Of 6 AML cases,2 achieved complete remission (CR),2 with partial remission(PR),1 with stable disease(SD),1 with progressive disease(PD).As to the 8 MDS patients,one achieved CR and 6 with hematologic improvement (HI),1 case SD.Low dose subcutaneous decitabine regimen could be an alternative choice of older AML or MDS patients.

Objective To observe whether the transplanted dermal multipotent stem cells(dMSCs)transfected by adenovirus vector of CXCR4(Adv-CXCR4)can distribute more frequently to the wound of rats with combined wound and irradiation injury.Methods dMSCs transfected by Adv-CXCR4(group A),or transfected by adenovirus vector of green fluorescent protein(group B),and non-transfected dMSCs were labeled with 3H-TdR and then transplanted into combine-injured rats.The amount of dMSCs in wound were determined by liquid scintillation,and wounds healing process was observed by measuring the remaining wound area.Results From the 5th day after transplantation,the amount of dMSCs in the wound of group A accounted for 1.95%-3.85% of the total transplanted dMSCs,significantly greater than those in group B and group C,which accounted for 1.07%-1.86% of the total transplanted dMSCs.The remaining wound area in group A was smaller than those in group B and group C from day 12 after injury,and the healing time of group A was 1.5 day ahead than group B and group C.Conclusions dMSCs transfected by Adv-CXCR4 distributes more frequently to the wound of combine-injured rats and could accelerate wound healing.