BACKGROUND:Studies have shown that Schwann cells form a Bunger band in the basement tube and guide the extension of regenerating axons after peripheral nerve injury, but the exact mechanism remains to be explored.
OBJECTIVE:To explore the effect of Wal erian degeneration on biological characteristics and secretory function of Schwann cells in rats with sciatic nerve injury.
METHODS:A rat model of sciatic nerve injury was established and divided into two groups:sciatic nerve transection group and surgical control group. Schwann cells were isolated and cultured from sciatic nerve segments by one enzyme digestion. The cellmorphology was observed under light microscope and S-100 protein expression was determined by immunofluorescence staining. After subculture, the first generation of Schwann cells were chosen to draw the growth curve by the counting method within 14 days. The cellactivity was detected by MTT assay. The adhesion of Schwann cells was examined by acid phosphatase analysis and the concentration of nerve growth factor was detected by ELISA method.
RESULTS AND CONCLUSION:At 14 days after primary culture, a great number of Schwann cells were observed near the edges of nerve segments in the sciatic nerve transection group, but only smal number of Schwann cells scattered around nerve segments in the control group. Schwann cells in both groups showed S-100 positive expression. At 3 days after subculture, Schwann cells reached the logarithm proliferative phase, the cellnumber and proliferation absorbance values in both groups were increased along with time extension. Furthermore, the number of Schwann cells and absorbance value in the sciatic nerve transection group were significantly higher than those of control group (P<0.05). The adhesion ability in the sciatic nerve transection group was also significantly higher than those in the control group (P<0.05). ELISA results showed that, the concentrations of nerve growth factor in the sciatic nerve transection group were significantly higher than those in the control group at 4, 6, 8, 10, 12 and 14 days (P<0.05). After sciatic nerve injury, Wal erian degeneration can induce Schwann cells dedifferentiate into the precursors, significantly influence the biological function of Schwann cells, promote the proliferation of Schwann cells within the short term, secrete large amounts of neurotrophic factors, enhance celladhesion, and provide a suitable microenvironment for regenerated axons. In addition, it creates the necessary microenvironment for peripheral nerve regeneration.

Objective To explore the clinical features of hepatocellular carcinoma (HCC) during pregnancy. Methods Clinical data of 4 patients with HCC in pregnancy were retrospectively analyzed.Results All 4 patients were positive for hepatitis B surface antigen. A marked increase in maternal serum a-fetoprotein (AFP) was found in 3 patients (310.1-5630.0 ng/ml ). Three patients were diagnosed at their advanced stages and died of disease in the 4th, 6th and 7th months, respectively. One patient diagnosed as having early HCC underwent curative surgery and has been without recurrence for 26 months. Conclusion The overall survival of patients with HCC in pregnancy is grim because most patients are diagnosed in the advanced stage. Surveillance with AFP and ultrasonography should be recommended for pregnant woman for the detection of early HCC, especially in hepatitis B virus carriers from high endemic areas, to improve patient survival.

Objective To construct a prostate cancer specific oncolytic adenovirus armed with a fusion protein gene , PSA-IZ-CD40L, and to evaluate its oncolytic efficiency and immune activation ability in vitro.Methods Prostate Specific Antigen (PSA) gene, CD40L-N and CD40L-C genes were obtained from cDNA of LNCaP cells and Jurkat cells using poly-merase chain reaction (PCR) or nested-PCR, respectively.PSA,Linker,CD40L-N and CD40L-C were linked sequentially to generate fusion protein gene PSA-IZ-CD40L (PL) by overlapping PCR.Then, prostate specific oncolytic adenovirus PL-carrying gene, Ad-PL-PPT-E1A,was constructed using the oncolytic adenovirus system , which was based on Adeasy sys-tem.PC3M cells were infected by Ad-PL-PPT-E1A at serial multiplicity of infection (MOI), and the apoptosis was detec-ted by flow cytometry at several time points post-infection.For immune activation detection , PC3M cells were infected with Ad-PL-PPT-E1A at a MOI of 50, and the cell lysate was collected at 48 h post-infection.Peripheral blood mononuclear cells derived (PBMCs) from healthy donors were stimulated by the lysate from PC 3M cells or Ad-PL-PPT-E1A infected PC3M cells before proliferation was assayed using cell counting kit-8 (CCK8).Results Fusion protein gene, PSA-IZ-CD40L, was successfully constructed and cloned into the prostate cancer specific adenovirus to generate Ad -PL-PPT-PL. The expression of E1A and PL protein could be detected by reverse transcription PCR and Western-blotting.Cytopathic effect was observed in PC3M cells infected with Ad-PL-PPT-E1A.Furthermore, the apoptosis rate reached 70.67% ± 2.98%at 48 h post-infection with 200 MOI Ad-PL-PPT-E1A.Compared with the lysate of PC3M cells, that from Ad-PL-PPT-E1A infected cells could promote the proliferation of PBMCs .Conclusion We have constructed a prostate cancer spe-cific oncolytic adenovirus armed can fusion protein gene PL , Ad-PL-PPT-E1A, which could kill PC3M cells effectively and enhance the proliferation of PBMCs in vitro.

According to ISO 10993 standard series, the biological safety of surface modified pure titanium was studied as a percutaneous device by the test of cytotoxicity in vitro, as well as by the tests of irritation and sensitization. The result from the examination of cytotoxicity in vitro was negative, the skin irritation response was negligible, and the result of test on skin sensitization in guinea pigs was also negligible. So the surface modified pure titanium in this study can be safely used as percutaneous implanting materials.
Animals ; Biocompatible Materials ; chemistry ; Coated Materials, Biocompatible ; chemistry ; Female ; Guinea Pigs ; Implants, Experimental ; adverse effects ; Materials Testing ; Rabbits ; Random Allocation ; Skin Irritancy Tests ; methods ; Surface Properties ; Titanium ; chemistry

The gentamicin sulfate carried calcium sulfate (GSCS) implants were fabricated by the coagulating method, and the release rate of the gentamicin tested by UV-spectrometer and the absorbing rate of the calcium sulfate carrier in vitro were studied. The release patterns of two types of GSCS were compared. The trend of daily weight loss of GSCS was found being similar to that of pure calcium sulfate, which suggested that the gentamicin part has little effect on the absorbing pattern of calcium sulfate. The release rate of gentamicin is controlled by the erosion rate of calcium sulfate, so GSCS with different amount of gentamicin has the same release patterns. The DRP value of ED is higher than that of CO during the early stage, while the DRP value of ED is lower than that of CO during the late stage. The GSCS samples were implanted into the defect mold on the radii of the rabbits to investigate the potential for the use of GSCS implants as bone fillers, and the results revealed that new bone had been induced in a great part of the defect at 14 weeks after operation.
Animals ; Anti-Bacterial Agents ; administration & dosage ; pharmacokinetics ; Bone Regeneration ; drug effects ; Calcium Sulfate ; administration & dosage ; Gentamicins ; administration & dosage ; pharmacokinetics ; Implants, Experimental ; Rabbits ; Radius Fractures ; therapy