Staphylococcus aureus ( S. aureus) is one of the most common human pathogens. It has been reported that Panton-Valentine Leukocidin (PVL) as a representative of virulence proteins is an important pathogenic factor for S. aureus infection. However, with the deepening of research, some researchers consider that pvl gene has little effect on the pathogenicity of S. aureus. This article aimed to review and summarize the recent studies on the features, molecular epidemiological characteristics, pathogenicity and controversy of pvl gene.

Brain injury is a kind of wound by violence on head, which is a mechanical distortion of skull, meninx, cerebral vascular and brain tissue due to outside force acting on head. Apolipoproteins E (ApoE ) is a major kind of apolipoprotein s, participating in the metabolismof lipid and regulating bal-ance of cholesterol. Some recent investigations showthat gene polymorphismof ApoE is associated with various kinds of diseases. Also its immunoreactivity is changed regularly with brain injury. In addition, ApoE has remarkable effect in neurological normal growth and reparative process after brain injury. This article reviews the biological characteristics and mechanismof ApoE in the repair of brain injury and application prospect in forensic medicine, which may be able to provide newideas for estimation of the brain injury time and related experimental research.

M etallothionein (MT) is a kind of metal binding protein. As an im portant mem ber in metalloth-ionein fam ily, MT-Ⅰ/Ⅱ regulates metabolismand detoxication of brain metal ion and scavenges free radicals. It is capable of anti-inflam matory response and anti-oxidative stress so as to protect the brain tissue. During the repair process of brain injury, the latest study showed that MT-Ⅰ/Ⅱ could stim ulate brain anti-inflam matory factors, grow th factors, neurotrophic factors and the expression of the receptor, and prom ote the extension of axon of neuron,wich makes contribution to the regeneration of neuron and has im portant effect on the recovery of brain injury. Based on the findings, this article reviews the struc-ture, expression, distribution, adjustion, function, mechanism in the repair of brain injury of MT-Ⅰ/Ⅱand its application prospect in forensic medicine. It could provide anew approach for the design and manufacture of brain injury drugs as well as for age estimation of the brain injury.

Objective To investigate the indicators for identifying diffuse axonal injury by blunt forces in forensic pathological practice. Methods The DAI model was produced by the fluid - percussion method in cats. The cerebral samples were stained by H. E. , Bodian, Kluver - Barrera stain and NF Immunohistochemistry. Changes of axons and myeline sheath were observed at different intervals after injury. Positive NF immunostained area in axons was measured, and the data was analyzed by SPSS 11.5 for windows. Results Changes of axons in subcortical white matter and brainstem were observed in the forms of swollen, waved and distorted axons in early stage after injury (1-2 hours). Markedly torn, vacuolated axons with formation of the retraction balls from 4 hours after injury were specifically demonstrated in NF immunohistochemistry (P

Matrix metalloproteinase 3 is one of matrix metalloproteinase family members, which degrades a wide range of components of the extracellular matrix and participates in tissue morphogenesis, wound healing and inflammation. In addition, matrix metalloproteinase 3 is involved in pathogenesis and progress of a spectrum of diseases and malignant tumors, such as rheumatic arthritis, arteriosclerosis, breast cancer, and so on. Recent studies have demonstrated that matrix metalloproteinase 3 may be a novel signaling proteinase from apoptotic neuronal cells to microglia, which results in degeneration of neurons in Alzheimer's disease and Parkinson's disease by activating microglia. There is also an association between genetic polymorphisms of matrix metalloproteinase 3 at promoter region 5A/6A and susceptibility of myocardial infarction. Decrease in serum concentration of matrix metalloproteinase 3 after myocardial infarction may be a useful parameter for diagnosing sudden death due to myocardial infarction in forensic practice. Expression of matrix metalloproteinase 3 varies with different types of brain injuries, suggesting that it may contribute to synaptic plasticity during functional recovery. To elucidate the time-dependent expression of matrix metalloproteinase 3 may provide a new way for wound age determination in the brain.

The present paper reports that the fenfluramine(FA), amphetamine(AP) and methamphetamine(MA) were extracted from the blood by the solid phase microextraction(SPME). The drugs were extracted for 15 min under the condition of 70℃ by a polydimethylsiloxane fiber. d5-methamphetamine(IS) was used as an internal standard. GC/MS was used for analysis with the injection method of derivatization on column. The ions at m/z 268(FA), m/z 240(AP), m/z 254(MA) and m/z 258(IS) in the selected ion minitoring chromatograms were selected for quantitation. Each compound was detectable at least 0 01～0 03 ?g/g. By determination of fenfluramine in poisoning blood, it is proved that this method would be demonstrated to be simple and accurate.

ABSTRACT:Objective To investigate whether medial cerebellar nucleus may be involved in the pathogenesis of post-stroke depression (PSD)and explore the pathway that mediates this effect.Methods Healthy SD rats were randomly divided into five groups:control group,stroke group,PSD group,medial cerebellar nucleus (Med)lesion group,and superior cerebellar peduncle (xscp)lesion group.The ethological score of depression was evaluated.The neurotransmitters of Glu and GABA in the lateral hypothalamic area were detected by high performance liquid chromatography.Results Compared with those in control group,the levels of GABA and Glu expressions did not significantly differ in the lateral hypothalamic area in stroke group (P > 0.05 ).In contrast,the levels in PSD group,Med lesion group and xscp lesion group were lower than those in stroke group to different extent (P <0.01). Conclusion These results preliminarily show that medial cerebellar nucleus may participate in the pathogenesis of post-stroke depression,which may be mediated by the cerebellum-hypothalamic pathway.

T A R D N A-binding dom ain protein 43 (T D P-43) is a highly conserved and w idely expressed nuclear protein. N ow adays, the expression of T D P-43 can be found in m ost neurodegenerative diseases such as A lzheim er's disease, w hich m akes it becom e a neurodegenerative disease associated m arker pro-tein. From the current research status at hom eland and abroad, and around the relationship betw een the expression of T D P-43 and brain injury, this article em phatically probes into the specific expression and function of T D P-43 in acute and chronic brain injury based on the know ledge of its biological charac-teristics, w hich aim s to explore the feasibility for determ ining the cause of death and the injury and dis-ability situations by T D P-43 in forensic pathology.

Objective To study the expression of p35 and p25 in rat after focal cerebral contusion and to provide experimental data for estimating brain injury time. Methods Fifty adult male SD rats were randomly divided into 0 h, 6 h, 12 h, 24 h, 3 d, 5 d, 7 d, 10 d after focal cerebral contusion, control and sham-operated groups (5 rats each group). The focal cerebral contusion rat model was established. The expression of p35 and p25 protein of the damage peripheral zone in brain were detected by HEstain-ing, immunohistochemistry and western blotting at different injury time. Results Alarge number of p35 protein and a small amount of p25 protein were expressed in control group and sham-operated group. After focal cerebral contusion, p35 presented unimodal change with time and p25 presented bimodal changes with time. Conclusion Expression of p35 and p25 showed different regularity with good time correlation, which could help to estimate the brain injury time.

To identify the prevalence and the distribution of ticks infected with spotted fever group rickettsiae (SFGR) in Xunke Area of Heilongjiang Province ,China ,partial outer membrane protein A gene (ompA) and citrate synthase gene (gltA) specific fragments were assessed using the PCR method .The positive products were sequenced .Result showed that the pres-ence of SFGR was 14 of 60 in detection Dermacentor silvarum cases ,while the overall positive rate was 23 .33% .Its nucleotide sequence of ompA showed 99 .3% and 99 .18% similarity with nucleotide sequence of Rickettsia sp .JL-02 and Rickettsia rao-ultii respectively .And the evolutionary positions of SFGR species were similar with Rickettsiamontana and Rickettsiamassili-ae .It's concluded that the nature focus of tick-borne spotted fever did exist in the area of Xunke Area of Heilongjiang Province , China .