Objective To investigate the changes in cathepsin B (CatB) expression in acutely photodamaged human dermal fibroblasts (HDFs) and their significance.Methods HDFs were isolated from the foreskin of children,and subjected to primary culture and subculture.The fourth-to eighth-passage HDFs were used in the following experiment.HDFs were divided into two groups to receive irradiation with different doses of ultraviolet A (UVA) for different durations (acutely photodamaged group) or remain unirradiated (control group).Cell counting kit-8 (CCK8) assay was conducted to evaluate the proliferative activity of HDFs after irradiation with UVA at 5,10,15,20 and 25 J/cm2 respectively.Western blot and quantitative real-time reverse transcription PCR were performed to measure the protein and mRNA expressions of CatB respectively in HDFs at 24,48 and 72 hours after exposure to UVA at 10 J/cm2,and at 48 hours after exposure to UVA at 10,15,20 and 25 J/cm2.Statistical analysis was carried out by analysis of variance and least significant difference (LSD) test using the SPSS 13.0 software.Results UVA radiation induced a decrease in the proliferative activity of HDFs.When the dose of UVA was ≤ 10 J/cm2,the survival rate of HDFs maintained higher than 85％,and significant differences were observed in cell survival rate between unirradiated and irradiated HDFs at 24,48 and 72 hours (all P ＜ 0.05).Western blot showed that the gray value of CatB protein in the acutely photodamaged group irradiated with 10 J/cm2 UVA was significantly higher than that in the control group at 24 hours (0.76 ± 0.14 vs.0.35 ± 0.01,P ＜ 0.05),48 hours (1.34 ± 0.38 vs.0.45 ± 0.12,P＜ 0.05) and 72 hours (0.82 ± 0.09 vs.0.61 ± 0.06,P＜ 0.05).Increased mRNA expressions of CatB were also observed in the acutely photodamaged group compared with the control group at 24 hours (0.149 ± 0.009 vs.0.089 ± 0.015,P ＜ 0.05),48 hous (0.173 ± 0.009 vs.0.091 ± 0.010,P ＜ 0.05) and 72 hours (0.185 ± 0.158 vs.0.111 ± 0.017,P ＜ 0.05) after UVA radiation at 10 J/cm2.The gray value of CatB protein was 0.99 ± 0.07,1.49 ± 0.14,1.89 ± 0.08,2.07 ± 0.06 in HDFs at 48 hours after exposure to UVA of 10,15,20 and 25 J/cm2,respectively,significantly higher than that in the control group (0.60 ± 0.05,all P ＜ 0.05).Similarly,the mRNA expression of CatB was up-regulated in HDFs at 48 hours after UVA radiation at 10,15,20 and 25 J/cm2 compared with the unirradiated HDFs.Conclusion The protein and mRNA expressions of CatB are up-regulated in acutely photodamaged HDFs induced by UVA radiation.

Objective A method was established for genotyping of hepatitis B virus (HBV A-D genotype),based on the PCR-restriction fragment length polymorphism (RFLP) created by Hinf Ⅰ,Ear Ⅰ,Apo Ⅰ action on an amplified segment of the S region.Methods Clinical diagnosis research.One hundred and twenty-eight HBV S sequences obtained from GeneBank were analyzed for restriction enzyme sites that would be genotype-specific.Restriction patterns following digestion with restriction enzymes Hif Ⅰ,Ear Ⅰ,Apo Ⅰ were determined to identify A-D HBV genotypes.The method was used to detect the HBV genotype of fifty severe hepatitis patients due to chronic hepatitis B in China.Then the detection results were confirmed by direct sequencing.Results The new genotyping method was established,named simple PCR-RFLP,which could identify HBV genotypes A to D.Genotypes B,C,B/C and A or D could be determined by a single step digestion with Hif Ⅰ.Eight patients of genotype A/B/C classified by single step digestion with Hif Ⅰ were conformed as genotype B variant by further digestion and direct sequencing.Extracted randomly and diluted into different concentration,three specimens were tested for genotype of HBV repeatedly and respectively.The results were all in accord with the originals,and the lowest detection limit of HBV DNA was 7 ～ 9 IU/ml.This was particularly useful in China where genotypes B and C were predominant.Twenty-three of genotype B and ten genotype C patients were classified from these fifty severe hepatitis B patients by a single step digestion with Hif Ⅰ through the simple PCR-RFLP method.The same results were also obtained by direct sequencing of PCR products (Kappa =1.00,P =0.001).The simple PCR-RFLP method was superior to direct sequencing in detecting HBV B/C polyinfection (9 cases and 0 case; x2 =18.00,P =0.001).Conclusions Both the sensitivity and repetitiveness of Simple PCR-RFLP method are satisfactory.It is superior to direct sequencing in detecting HBV B/C polyinfection,and simple,convenient.

Objective To evaluate the performance of a DNA microarray method for detecting HBV antiviral drug-resistant mutations. Methods Two hundred and twenty four serum samples from patients with CHB were tested in parallel by DNA microarray and direct sequencing for the mutations within the HBV reverse transcriptase (rt) region, which included rtL180, rtA181, rtM204 and rtN236. Samples with discrepant results were retested by clonal sequencing. Results Complete concordance between DNA microarray and direct sequencing results was observed in 214 out of 224 samples (95. 5% ). The presence of mixed viral populations in the other 10 samples detected by DNA microarray but not by direct sequencing was confirmed by clonal analysis. The DNA microarray could detect minor viral populations which constituted 5.0%-15. 0% of the total viral load. Conclusion DNA microarray is highly consistent with direct sequencing in detecting HBV mutations conferring drug resistance and more sensitive in detecting mixed mutant and wild-type sequences than direct sequencing, which makes it a useful tool for early detection of drug resistance early.

[Objective] To study the effect of electroacupuncture on NO, NOS and ET - 1 levels in rats with focal cerebral ischemia (FCI). [Methods] Rat models with FCI were established by occlusion of unilateral middle cerebral artery. Twenty - two rats were allocated to three groups: Group A (mimic operation group), Group B (model group) and Group C (model rats treated with electroacupuncture). NO, NOS and ET - 1 levels in brain homogenate were measured by spectrophotometry and radioimmunoassay method respectively. [Results] Sixty minutes after modeling, NO, NOS and ET- 1 levels were increased and then decreased 10 minutes after acupuncturing Baihui (GV20) and Dazhui (GV14). [Conclusion] Electroacupuncture of Baihui (GV20) and Dazhui (GV14) can protect neuron from ischemic injury by decreasing the levels of NO and ET - 1 and inhibiting the activity of NOS.

Objective:To study the antiviral effect of ISG20 on HCV replicon.Methods:Wild type ISG20/mutated ISG20 cDNAs were obtained by RT-PCR/two step-PCR directed mutagenesis, and wild type ISG20 and dominant negative mutated ISG20 mammal expression vectors were consuructed. The constructed pISG20wt and pISG20m expressing vectors were transfected into Huh7 cells or Huh7 cells containing HCV replicon to investigate its effects on HCV replicon replication.Results:The ISG20wt/ISG20m expression vectors were constructed and the expressions of these two vectors were confirmed at both mRNA and protein levels. The effects of ISG20wt on HCV replicon replication were evaluated by Northern blot and Western blot. The results showed that expression of ISG20wt had significant inhibitory effect on HCV RNA replication.Conclusion:ISG20 participates in the anti-HCV action of IFN-? on HCV replicon system.

Objective To evaluate tension-free repair in the management of recurrent inguinal hernia. Methods From 1/1993 to 12/2002, 163 patients with recurrent inguinal hernia underwent reoperation, clinical data were reviewed. Results The male: female ratio was 138: 25, age from 34 to 76 years. The primary surgery had been traditional hemiorrhaphy without prothesis in 142 cases (87. 1 % , including 65 cases of Bassini ,35 cases of McWay and 42 cases of Shouldice) , a tension-free procedure in 12 cases(7. 4% , including 3 cases of laparoscopic mesh repair) and unknown techniques in 9 cases(5. 5% ). The average interval from the initial surgery to recurrence was 36?14 months (range from 3 months to 10 years). Recurrent hernias were treated with a Shouldice repair in 71 cases(43. 6% ) , a tension-free repair in 92 cases(56. 4% , including a laparoscopic mesh repair in 3 cases). All these 163 cases(100% ) were followed up for 56 ?1 months (range from 30 months to 12 years) after the second surgery. It was found that after reoperation the recurrence rate of Shouldice procedure and tension-free repair was 16. 1% (11/71) and 2. 2% (2/92) respectively (x2 = 8. 327 ,P

This paper elaborated that wheelchairs are the most important assistive devices for people with mobility impairment to maintain their health, improve their quality of life and promote their social participation. The situation of low service level was analyzed due to the lack of knowledge, organizations, professionals and products. Based on the foreign standard of practice for wheelchair service, the strategies and steps of wheelchair service provision in China were carried out to arouse the attention of relevant professionals, who could be active participants in wheelchair service practice and research

Objective To observe the expression changes of cathepsin K (CatK) in human dermal fibroblasts at different time points after different doses of ultraviolet A (UVA) irradiation.Methods Dermal fibroblasts were isolated from circumcised foreskins of children,and subjected to primary culture and subculture.Cells at third-tenth passage were used in the following experiment.Some fibroblasts were irradiated with UVA of 10 J/cm2 and collected at 24,48 and 72 hours separately after the irradiation,and some fibroblasts were irradiated with UVA of 10,20 and 30 J/cm2 separately and harvested 48 hours later.The fibroblasts receiving no irradiation served as the control group.Reverse transcription PCR and Western blot were carried out to detect the mRNA and protein expressions of CatK in fibroblasts,respectively.Results Compared with the control fibroblasts,those irradiated with UVA of 10 J/cm2 showed a significant elevation in the mRNA and protein expression levels of CatK on day 1 (0.351 ± 0.038 vs.0.177 ± 0.006,1.76 ± 0.27 vs.0.82 ± 0.45,respectively,both P＜ 0.05),day 2 (0.510 ± 0.017 vs.0.176 ± 0.002,2.97 ± 0.36 vs.1.58 ± 0.15,respectively,both P＜ 0.05) and day 3 (0.313 ± 0.012 vs.0.173 ± 0.002,2.23 ± 0.14 vs.1.29 ± 0.32,respectively,both P ＜ 0.05),with the highest expressions of CatK mRNA and protein observed on day 2.Within the range of 10-30 J/cm2,UVA enhanced the CatK mRNA and protein expression levels in a dose-dependent manner.In detail,at 48 hours after the irradiation with UVA of 10,20 and 30 J/cm2,the CatK mRNA expression level in the irradiated fibroblasts was 2.34,2.91 and 3.18 times,and the CatK protein expression level 1.77,2.82 and 3.64 times,respectively,that in the control fibroblasts (all P ＜ 0.05).Conclusion The expression of CatK is up-regulated in human dermal fibroblasts after UVA irradiation.

BACKGROUND:Exosomes are membrane vesicles secreted by mesenchymal stem cells. Increasing studies have shown that mesenchymal stem cells can secrete exosomes via paracrine function to play a role in tissue injury. However, reports on how to isolate and identify exosomes derived from human umbilical cord blood mesenchymal stem cells are few. OBJECTIVE:To extract, purify and identify exosomes derived from human umbilical cord blood mesenchymal stem cells. METHODS:The cellculture supernatant of human umbilical cord blood mesenchymal stem cells was col ected. Exosome was extracted and purified with ultrafiltration and gradient centrifugation methods. The morphology of exosome was observed by transmission electronic microscope, and the expressions of CD63, CD81, CD90, CD73, CD105, CD29, and CD166 in exosome of mesenchymal stem cells were analyzed by fluorescent activated cellsorting. RESULTS AND CONCLUSION:Mesenchymal stem cells from human umbilical cord blood secreted exosome which exhibited el iptic or saucer-like shape and its diameter ranged from 40 to 100 nm with membrane structure. Exosome could express the common surface adhesion molecules CD63, CD81 and the surface adhesion molecules CD90, CD73, CD105, CD29, CD166 of mesenchymal stem cells. These findings indicate that exosome may be secreted by mesenchymal stem cells of human umbilical cord blood, which contains plasma membrane proteins of umbilical cord blood mesenchymal stem cells.