Timing of death is one of the important problems in forensic pathologic practice.Using histochemical methods,the authors observed the enzyme activity changes ofPPr,CCo,ACP,ANAE,LDH,SDH,G6PD,NADHD,G-6-Pase and ATPase inmice liver cells at 0,6,12,24,48,72 hours postmortem(HPM) at the environmen-tal temperature 4℃ and 20℃.The results showed that at 20℃,PPr activity dec-reased markedly at 6 HPM,LDH and ATPase activity decreased at 48 HPM anddisappeared at 72 HPM.The another seven enzymes still showed good enzyme acti-vity at 72 HPM.The authors supposed that the results are significant for timingof postmortem duration.

Objective To evaluate immune protective effects of Treponema pallidum(Tp)pcD/Tp92 DNA vaccine delivered through different inoculation routes against Tp-induced skin infection in New Zealand rabbits. Methods A total of 108 New Zealand rabbits were randomly and equally divided into 6 groups:A1 and A2 groups treated with intramuscular injection of empty plasmids pcD and pcD/Tp92 DNA vaccine respectively for 2 sessions, B1, B2, C1 and C2 groups firstly treated with intramuscular injection of the pcD/Tp92 DNA vaccine for 1 session for primary immunization, then receiving nasogastric feeding with pcD/Tp92 DNA vaccine, pcD/Tp92 DNA vaccine+cytosine-phosphate-guanine(CpG)oligodeoxynucleotide (ODN), and recombinant Tp92 protein, and recombinant Tp92 protein+CpG ODN respectively for booster immunization. Enzyme-linked immunosorbent assay(ELISA)was conducted to detect the serum level of anti-Tp92 IgG antibody at week 0, 2, 4, 6, 8 after immunization, the SIgA level in the nasopharyngeal region and vaginal mucosa at week 8 after immunization, as well as levels of interleukin-2(IL-2)and interferon-γ (IFN-γ)in the culture supernatant of rabbit spleen cells at week 8 after immunization, and methyl thiazolyl tetrazolium(MTT)assay was performed to estimate proliferative activity of rabbit splenic lymphocytes in three rabbits from each group. At week 10 after immunization, other 15 rabbits from each group were subcutaneously inoculated with Tp standard strain, and changes of skin lesions at the inoculation site during early-stage infection were observed and recorded. Results At week 8 after immunization, the C2 group showed significantly higher serum level of anti-Tp92 IgG antibody(1.825 ± 0.175), supernatant levels of IL-2 (154.7 ± 14.6)and IFN-γ(277.4 ± 24.4), and proliferative activity of T cells(3.57 ± 0.24)compared with the A2(1.372 ± 0.322, 112.3 ± 13.4, 232.8 ± 25.3, 3.08 ± 0.22, respectively, all P<0.05), B1(0.893 ± 0.297, 76.6 ± 21.5, 165.7 ± 22.6, 2.12 ± 0.14, respectively, all P<0.05)and B2(1.294 ± 0.124, 97.3 ± 18.7, 211.3 ± 24.6, 2.88 ± 0.18, respectively, all P<0.05)groups. In addition, effective immunoprotection was achieved in the C2 group with more production of mucosa-specific SIgA antibody, as well as the lowest Tp-positive rate (6.67%) and ulcer formation rate (6.67%) in skin lesions at the inoculation sites. Conclusion The effective vaccination strategy, namely intramuscular injection of the pcD/Tp92 DNA vaccine for primary immunization followed by nasogastric feeding with mucosal adjuvant CpG ODN combined with recombinant Tp92 protein for booster immunization, can induce the strongest mucosal immune responses and immune protective effects.

Objective To clone,express,and purify Tp 0319 outer membrane protein of Treponema pallidum and to develop an indirect ELISA for diagnosing syphilis.Methods The expression plasmid PQE32/Tp 0319 was conventionally constructed.The recombinant Tp 0319 protein was produced in E.coli M15 after induction by IPTG.The Tp 0319 protein was analyzed by SDS-PAGE and Western blotting,and then purified with Ni-NTA affinity chromatography.Indirect ELISA was developed to detect the syphilis antibody in human sera.Results The recombinant plasmid PQE32/Tp 0319 was constructed successfully and the fusion protein with relative molecular weight near 30 000 Dalton was revealed by SDS-PAGE.Western blotting proved that the recombinant protein specifically reacted with anti-Tp antibodies in sera from syphilis patients.The results of the indirect ELISA indicated the sensitivity and the specificity were both 100%.The concordance of 300 sera(150 from blood donors and 150 from syphilis patients)detected in parallel by the ELISA and the TPPA was 95.3%.Conclusions The data suggest that the prepared recombinant protein Tp 0319 of Treponema pallidum has high immunoreactivity.The recombinant protein can be used to develop ELISA kit for diagnosing syphilis.

Objective To clone.and express Tp0453 outer membrane protein of Treponema pallidum and develop an indirect ELISA for sero diagnosis of syphilis. Methods The immuno-dominant epitope of Tp0453 was amplified by PCR and subcloned into the expression vector pQE32.The recombinant protein was expressed in E.coli M15 and purified with Ni-NTA affinity chromatography columns. Indirect ELISA was developed to detect the antibody to Tp in human sera.Results 60 control sera was tested by ELISA.The sensitivities was 100%(30/30), and the specificities was 100%. While detecting uninfected and infected T. pallidum human sera, the sensitivities of ELISA was 96.8% compared with the results of the TPPA tests, and the specificities was 100% when the results of ELISA was compared with those of the TPPA test. The concordance of results between the ELISA test and the TPPA test was 98.2%.Conclusion The recombinant Tp0453 outer membrane protein showed excellent immuno-reactive activity, and were suitable for development of ELISA for sero-diagnosis of syphilis.

Objective To express Tp0751 laminin-binding adhesion of Treponema pallidum (T. pallidum) ,and assess the immunocompetence. Methods The Tp0751 ORF without upstream non-cod-ing region was ligated into the expression vector pET-28a( + ), and expressed in E. coli R2566. Its immuno-gen was analyzed by Western blot and ELISA. Results A fusion protein with molecular weight about 26×103 was attained after expression and purification. Western blot proved that the recombinant protein can specifically react with T. palliclum IgG positive sera. Specific humoral response were elicited after introducing recombinant protein in Zealand rabbit and the specific antibody titer was above 1:10 2400 detected by indi-rect ELISA. Conclusion The expressed recombinant protein showed excellent immunoeompetence, and the results lay the foundation for the research on its function to T. paUidum infection.

Objective To assess the clinical efficacy of minimally invasive internal fixation combined with percutaneous kyphoplasty (PKP) in treatment of thoracolumbar burst fractures in the elderly.Methods Twenty-one cases of neurologically intact thoracolumbar burst fractures treated by PKP between January 2007 and December 2008 were included in this study.There were 8 males and 13 females at age of 65-78 years (means,70.6 years).Mean period from injury to operation was (3.7 ± 1.1) days (range,3-7 days).The injured segments included Ti1 in two cases,T12 in six,L1 in eight and L2 in five.Kphosis Cobb' s angle,correction degree of kyphosis angle,correction loss of kyphosis,perioperative indicators,visual analogue scale (VAS) and Oswestry disability index (ODI) were evaluated after operation.Results All the cases were followed up for a period of 26-56 months (mean 34.2 months).Operation averaged 98.7 minutes (range,80-120 minutes) and showed mean blood loss of 32.8 ml (range,30-85 ml).Ambulation started at mean 18.2 hours after operation (range,8-19 hours).VAS averaged (0.9 ± 0.6) points at postoperative one week.Postoperative X-ray films revealed mean 10.4° correction of kyphotic Cobb angle,followed by mean 1.8 °of loss in the follow-up longer than 24 months.According to hyperextension and hyperflexion radiographies,there was no abnormal activity of fixed segments,implant loosening and breakage or adjacent vertebral fractures.Conclusion Minimally invasive internal fixation combined with PKP can relieve pain and restore function in a short time and is thought to be a preferable treatment option for thoracolumbar burst fractures in the elderly.

Objective To construct a recombinant plasmid encoding Tp0821,a membrane lipoprotein of T. pallidum,express and purify this protein,and to evaluate its immunocompetence.Methods The recombinant plasmid pQE32/Tp0821 was constructed and induced to express the corresponding protein.Then,New Zealand rabbits were immunized with purified recombinant protein to prepare polycional antibodies,and the titer of polyclonal antibody was determinated.Indirect ELISA was developed with the recombinant protein of T. pallidum as coating antigen to detect 80 control sera and 150 FTA-ABS-positive sera.Results The recombinant plasmid pQE32/Tp0821 was constructed and a fusion protein with expected molecular weight was expressed.Specific humoral response was elicited by the recombinant protein in New Zealand rabbits and the antibody titer reached 1:6400.Compared with FTA-ABS test,the indirect ELISA showed a sensitivity and specificity of 92.6%and 98.6%,respectively,in the detection of control and clinical sera.Conclusion The recombinant protein Tp0821 shows excellent immunocompetence,which can be applied to the serological diagnosis of syphilis.

Objective To clone, express Tp0319 gene from Treponemapallidum (T. pallidum), and to assess the immunocompetence of recombinant protein. Methods The immuno-dominant region of Tp0319gene was chosen by computer analysis, amplified from T. pallidum complete genome by PCR, subcloned into the expression vector pQE32 to construct a recombinant plasmid, pQE32/Tp0319, which was then expressed in E. coli M15. The recombinant protein was purified with Ni-NTA affinity chromatography, and identified by using sodium dodecyl sulfate polyacrylamide gel electropheresis (SDS-PAGE) and Western blot. New Zealand rabbits were immunized with the recombinant protein, and the titer of anti-Tp0319 antibodies in sera from immunized rabbits were measured with indirect ELISA. Also, indirect ELISA with the recombinant Tp0319 as coating antigen was performed to detect the anti-Tp0319 antibody in sera from 200 normal human controls and 200 patients with syphilis. Results The prokaryotic expression vector pQE32/Tp0319 was constructed successfully, and the recombinant protein Tp0319 with a molecular weight of about 30 000 was attained. Specific humoral response was elicited by the recombinant protein in New Zealand rabbits and the specific antibody titer was more than 1: 10 240 after immunization for 3 times. Western blot proved that the recombinant protein could specifically react with anti-T. pallidum IgG antibody-positive sera. Indirect ELISA was successfully developed with the recombinant Tp0319, and detected antibodies to T. pallidum in control sera with a sensitivity and specificity of 100% (40/40), respectively. Compared with T. pallidum particle agglutination (TPPA) assay, the sensitivity and specificity of the indirect ELISA were 92.6% and 100%, respectively, in the detection of T. pallidum in sera from patients and controls, and the concordance between the indirect ELISA and TPPA was 96%. Conclusions The prepared recombinant protein shows a satisfactory immunocompetence, which may lay a foundation for its further application in the serodiagnosis of syphilis.

Objective:To observe the effect of Kechuanning on Th cytokine expression in pediatric virus-induced asthma.Methods:120 cases of pediatric virus-induced asthma were randomly divided into Kechuanning group(treatment group,n =60,treated with Kechuanning) and Western medicine group(control group,n=60,treated with virazole).The change of Th1 cytokine IL-12 and Th2 cytokine IL-4 in blood serum were detected and analyzed.Results:Kechuanning could increase IL-12 but decrease IL-4 level in the patient's blood,therefore regulate Th cell subset,and the effect was more obvious than in control group.Conclusion:The mechanism of Kechuanning in curing pediatrics asthma induced by virus was related with increasing IL-12 and decreasing IL-4 level.

Objective To evaluate the clinical effect of interspinous H-shaped bone grafting and bilateral facet interbody fusion in treatment of thoracolumbar fracture with severe disc injury and posterior ligamentous complex (PLC) injury after posterior pedicle screw fixation and its role in prevention of delayed kyphosis.Methods The study involved 19 cases of thoracolumbar fractures with severe disc injury and PLC injury,including 11 males and 8 females,at age of 23-59 years (mean 43.8 years.All cases were treated with posterior pedicle screw fixation (including 11 cases treated with unilateral laminectomy decompression) and C-arm X-ray showed favorable fracture reduction.For prevention of postoperative delayed kyphosis,the interspinous H-shaped bone grafting plus bilateral facet interbody fusion by using the iliac autografts was done.Neurologic recovery was assayed by using Frankel scale and lumbar and iliac pain by visual analogue scale (VAS).Cobb angle was detected as well.Results All cases were followed up for 24-64 months.At final follow-up,all cases showed neurological improvement for at least 1 to 2 Frankel grades except for two cases with Frankel Grade A,with mean Cobb angle of (2.0 ± 3.7) ° (range,-4.9°-8.1 °),mean VAS of lower back pain of (1.1 ± 1.2) points (range,0-4 points) and insignificant angle loss or kyphosis.The thin layer CT scan indicated complete integration of the transplanted bone grafts,with no complications like implant loosening or breakage.Conclusion Interspinous H-shaped bone grafting and bilateral facet interbody fusion is a good choice for prevention of delayed kyphosis after posterior pedicle screw fixation of thoracolumbar fracture with severe disc injury and PLC injury.