In the present study an experimental animal model of closed chest cardiac contusion in dogs was successfully established by impacting precardial area at the velocity of 9- 1 - 10. 5m/s with home-made elastic cord propelled impactor, After impact, some significant abnormalities of the left and right ventricular pressure,ECG and heart rate were recorded. Cardiac contusions were demonstrated at au-topsy. The establishment of the experimental cardiac contusion model could provide the tool for further study on nonpenetrating cardiac injury.

Objective To understand the gene E sequences of prevalent strains of Dengue fever type Ⅰ virus in Zhaoqing City during 2014.Methods The medical record data and acute stage serum of the patients with Dengue fever in Zhaoqing City during 2014 were collected.Dengue virus was cultured and isolated by using the C6/36 cell culture.Gene E of positive strains was amplified with RT-PCR.The phylogenetic tree was drawn and the bioinformatics analysis was conducted.Results Of 36 samples,20 samples were positive in viral isolation and culture.The gene E sequences of 20 strains of type Ⅰ Dengue virus prevalence in Zhaoqing dur-ing 2014 were obtained;the homology of these sequences was close to that of the 2 prevalent strains found in Zhongshan City,but was distant from that found in Guangzhou City.Conclusion The epidemic situation of Dengue fever in Zhaoqing City is closely re-lated to the prevalence situation of Zhongshan and is characterized by imported prevalence.

Objective To evaluate the influence of different antigen retrieval methods and pH values of fixatives on immunostaining of incised wound skin.Methods 3d-post-incision mouse skin were sampled and fixed in 4% formalin buffered with PBS at pH 5.0,6.0,7.0,8.0 and 9.0.The deparaffinized sections were treated 0.01mmol citrate buffuer(pH 6.0)in high pressure cooker or by microwave heating,or with pepsin,trypsin or microwave+pepsin.Thereafter,immunostainings of caspase-3,caspase-6,caspase-7,IL-8,and IL-10 were evaluated by immunohistochemical SABC method with ratio of immunostaining-positive cells,respectively.Results The immunostaining-positive cell ratios in sections treated by heating retrieval was higher than by proteinase treatment.The positive cell ratio was slightly higher by high pressure than by microwave heating.Sections were more easier peeled off during high pressure treatment than during micrwave heating.Sections treated with pepsin were fallen off easier than with trypsin digestion.The highest positive cell ratio was detected in sections by microwave+trypsin treatment without section peeling off among all antigen treatment methods.The best result was obtained in sections fixed in buffered formalin at pH 7.0 and 8.0.Conclusion The best immunostaining result may be obtained in mouse incised wound sections fixed in buffered formalin at pH 7.0 and 8.0 with microwave+trypsin treatment.

Focal adhesion kinase(FAK)and extracellular signal-regulated protein kinase(ERK),which are thought to play major roles in transducing surface receptor-derived signals into nucleus,are pivotal signal transduction molecules in mammalian cells.FAK is activated through phosphorylation by extracellular stimuli.p-FAK activates the downstream of ERK which changes cell action.FAK-ERK signal conduction factors are involved in a variety of biological responses,such as cell proliferation,differentiation,stress,apoptosis and malignant change.The biologic characters of FAK-ERK and advances in the study on its roles in tissue damage are reviewed in this article,which may provide a more effective way for estimation of wound age in forensic medicine.

To explore the applicability of interleukin 8(IL 8)to determination of wound age in the incised and stabbed human skin samples,an immunohistochemical study on the temporal expression of IL 8 was performed on 52 human skin wounds at different posttraumatic intervals.Expression of IL 8 was detectable in polymorphonuclear cells(PMNs)in the wound specimens aged 4h.In the wound specimens aged from 12～24h after injury,IL 8 was identified in a large number of infiltrating PMNs and part of mononuclear cells(MNCs).Afterwards,the MNCs and fibroblastic cells(FBCs)accounted in the most part of the IL 8 positive cells.Morphometrically,the ratio of the number of the IL 8 stained PMNs,MNCs and FBCs to total number of the cells in the wounds was evaluated and calculated.The ratio of the IL 8 positive cells was low in the wound specimens aged 4 and 6h(16 0?10 1%),and maximized in the wound specimens aged between 1 and 4 days(59 6%?8 7%).Thereafter,the ratio decreased and minimized in the specimens aged from 19 to 21 days(27 5?5 9%).The results suggest that IL 8 can be used as a marker for the wound age determination in both incised and stabbed human skin.

Objective To investigate the expressions of caspase-6,-7 during skin wound healing and the applicability of the time-dependent expressions of caspase-6,-7 to determination of the wound age.Method The expressions of caspase-6,-7 were studied in skin incised wound in mice by immunohistochemical SABC method,and the non-incised mouse skin was used as control.Results Expressions of caspase-6,-7 were detectable in polymorphonuclear cells (PMNs) in the wound specimens aged 6h. In the wound specimens aged from 12h to 24h after injury, caspase-6,-7 were identified in a large number of infiltrating PMNs and part of mononuclear cells (MNCs). Afterwards, the MNCs and fibroblastic cells (FBCs) accounted for the most part of the caspase-6,-7-positive cells. Morphometrically, the ratios of the number of the caspase-6,-7-stained PMNs, MNCs and FBCs to total number of the cells in the wounds were evaluated and calculated. The ratios of the caspase-6,-7-positive cells were low in the wound specimens aged from 0h to 3h, and maximized in the wound specimens aged 3 day. Thereafter, the ratios decreased and minimized in the specimens aged 14 day.Conclusion The results suggest that caspase-6,-7 were expressed in neutrophils, macrophages and fibroblasts during healing process of skin incised wound in mice. Caspase-6,-7 may be used as a marker for the wound age determination.

Hitherto, it is reported that caspase family includes 14 members at least, which play important roles in executing cell apoptosis. Experimental studies have proved that caspases are expressed and activated in the injured skin and during skin wound healing, which suggests that cell apoptosis induced by caspases may occur. Further investigation on the roles that caspases play in the injured skin and during skin wound healing may offer a new way for the clinical treatment of the skin wound and the medico-legal wound age determination. The article reviews the biologic characters of caspases and the advances in the studies on the caspases in the skin wound and wound healing. It is suggested that caspases exert significant parts during skin wound healing, which are worthy of further investigation.

Oncogene c-jun is a member of jun family,the immediately early genes(IEGs),and belongs to one of the nuclear transcription factors of basic leucine zipper(bZIP)family.Combined with many gene promotors,c-jun is involved in the regulation of gene transcription.Its products play important roles in regulating gene expression,cell proliferation,differentiation and apoptosis.The structure,biological funetion,regulation of c-jun and its roles contributing to tissue damage are reviewed in this article,which may provide understanding for severity of tissue injury and wound age estimation in the field of forensic pathology.

Objective To evaluate the clinical efficiency of posterior unilateral open-door laminoplasty and leverage titanium plate internal fixation in the treatment of cervical spondylotic myelopathy ( CSM ) with multi-segmental spinal stenosis.Methods Between Mar 2011 and May 2015, 25 patients with multi-segmental CSM with multi-segmental spinal stenosis were treated by posterior unilateral open-door laminoplasty and leverage fixation .There were 16 males and 9 females, whose mean age was 60.6 ±9.9 years during the surgery.The change of clinical symptoms and signs was recorded during follow-up,and they all received X-ray and MRI.In all the patients, the preoperative and postoperative neurological function, the cervical curvature,cervical vertebra tube volume and axial symptoms were measured , recorded and analyzed. There was statistically significant difference (P<0.05) in the mean Japanese Orthopaedic Association (JOA) score, and Visual Analogue Scale ( VAS) .Results All the 25 patients were followed up for more than 6 months ( 6-24 months ) .No symptoms of C5 nerve root were found in our series .According to the JOA score and VSA score ,the neurological functions of each patient were significantly improved .The preoperative JOA score was 10.16 ±1.35 and the improvement rate 61.24%. There was statistically significant difference between the preoperative VSA score and the postoperative one (6.68 ±1.12 vs 2.32 ±0.84) ( P<0.05).The preoperative and postoperative meansurement of the spinal vertebrai canal diameter was (9.22 ±2.01) and (15.64 ±2.08) mm, respectively,so there was statistically significant difference (P <0.05), indicating that the cavical spinal canal was increased after operation .Conclusion Leverage titanium plate internal fixation can effectively help maintain the expanded vertebral canal after unilateral open -door laminoplasty ,reduce the incidence of postoperative axial symptoms , and maintain the cervical physical curvature .

Objective To study the percentages of polymorphonuclear leukocytes (PMN), mononuclear cells (MNC) and fibroblastic cells (FBC) in different post-traumatic intervals after skeletal muscle me-chanical injury in rats. Methods The rat model of skeletal muscle mechanical injury was established. The rats were divided into injured groups (6 h, 12 h, 1 d, 3 d, 7 d, 10 d and 14 d after injury ) and con-trol group. The percentages of PMN, MNC and FBC in different post-traumatic intervals after skeletal muscle mechanical injury were assessed with HE staining and image analysis. Results At post-injury 6-12 h, the percentages of PMN and MNC infiltration appeared in injured sites and that of PMN reached peak. At 1 d, the percentage of MNC infiltration appeared and reached peak, while that of PMN de-creased. At 3-7 d, the percentage of FBC gradually increased, while that of PMN and MNC decreased. At 10-14 d, the percentage of FBC reached peak. Conclusion The percentages of PMN, MNC and FBC in injured zones showed time-dependent changes, which might be used as reference index for determination of age of skeletal muscle injury.