Objective To screen enterohemorrhagic Escherichia coli(EHEC) strain and declare it as a standard strain of China Medical Bacterial Species Conservation and Management Center(CMCC).On the base,to prepare strain reference and genomic DNA reference of EHECand declare them as national drug reference with independent intellectual property rights in our country.Methods According to GB4789.6-2016 National Food Safety Standards-Food Microbiology TestDiarrheagenic Escherichia coil Test,the EHEC strain was screened from 160 Escherichia coli strains from patients with diarrhea and declared as a standard strain of CMCC according to management regulations.EHEC bacterial solution and genomic DNA solution were prepared,and freeze-drying technology was used to prepare 600 strain(10~3 CFU/sample) and genomic DNA(20 ng/sample) samples respectively.20 strain and 20 genomic DNA samples were randomly selected for uniformity test.Samples storing at 25 ℃ and 37 ℃ for 1,3,5 and 7 d were taken respectively to test the transportation stability.Then the samples were tested for the short-term storage stability by storing at 4 ℃ for 7,14 and 28 d,and for the long-term storage stability by storing at 20 ℃ for 14,28 and 60 d.Three laboratories were organized for collaborative calibration.20 food products were chosen as the substrate to evaluate the application effect of strain samples.Results The one EHEC strain selected from 160 Escherichia coli strains from patients was finally declared as the CMCC(B) 43207standard strain.In the uniformity test,F_(strainsample)=0.662 0.05,and eae,stxl and stx2 of 20genomic samples were all positive.After storage at 25 and 37 ℃ for 7 d,-20 ℃ for 60 d and 4 ℃ for 28 d,the viable bacteria content of the strain samples was still 103 CFU/sample,and eae,stxl and stx2 of the genomic samples were positive.EHEC strains and genomic DNA samples selected randomly were identified as EHEC by three laboratories,the viable bacteria content was 10~3 CFU/sample,and eae, stxl and stx2 were all positive.It was detected in 20 kinds of food substrates after adding samples,but not in the background control.EHEC strain and the genomic DNA sample were included in drug standard materials in our country,numbered 80024 and 80056,respectively.Conclusion The prepared EHEC strain and genomic DNA standard materials with independent intellectual property rights can improve the timeliness of EHEC testing and make up for the gap in our country.

The internet addiction disorder is an important problem under the internet circumstance.Improving self-regulated ability is a good method to avoid the problem.The article uses the selfregulated circle theory to gain the self-regulating strategy in three phases:forethought,performance or volitional control,self-reflection.These strategies include making goal,planning strategy,self-observation and self-record,attribution.

Anoikis is a special programmed cell death and plays important roles in both physiological regulation and pathogenesis of many diseases, including atherosclerosis, acute coronary syndrome, cardiac failure, aneurysm and tumors. This review focuses on the association of the anoikis with instability and rupture of atherosclerotic plaque.

Transient ischemic attack (TIA) is the most important early warning signal of cerebral infarction, and it is also the critical period for the prevention of cerebral infarction. If we effectively control the risk factors of TIA, the onset and the progress of TIA can be prevented and controlled, This article reviews the correlation between the risk factors of TIA and prognosis.

OBJECTIVE: Controversy over the presence of neuronal apoptosis in acute brain injuries has not been resolved due to the lack of direct evidence. In this article, the authors briefly review the current research progress of apoptosis and discuss the relationship between acute brain injuries and neuronal apoptosis.DATA SOURCES: A computer-based retrieval for relevant papers with abstracts indexed in Medline database published in English full text between January 1995 and February 2005 was conducted using the key words of "acute brain injuries" and "Neuronal apoptosis". Related articles in Chinese full text published between January 2000 and December 2004 were also searched in Chinese periodical full text database, Wanfang databases with key words of "acute traumatic brain injury, neuronal apoptosis".STUDY SELECTION: The retrieved articles were first examined to exclude review articles and repetitions, and only randomized and non-randomized controlled experiments or clinical trials on acute traumatic brain injury and neuronal apoptosis were included.DATA EXTRACTION: Altogether 136 articles directly related to acute traumatic brain injury and neuronal apoptosis were collected, among which 19 met the inclusion criteria with the other 117 removed for repetition or irrelevancy.DATA SYNTHESIS: The valid articles were reviewed to identify the factors related to neuronal apoptosis, apoptotic network theory, detection methods of apoptosis, and the relationship between acute traumatic brain injury and neuronal apoptosis as well as the possible mechanisms.CONCLUSION: Neuronal apoptosis occurs after acute traumatic brain injury, which induces intrinsic and extrinsic neuronal environment changes including increased extracellular excitatory amino acid content, massive free radical production and abnormal gene expression. These factors interact with each other and modulate neuronal apoptosis through multiple pathways.

OBJECTIVE: To probe into the progression of biochemical study on caspase-3 and its functions in disorders of center nerve system.DATA SOURCES:The relevant papers were looked up on Medline database from January 1995 to February 2005 with the retrieved words as"caspase-3", "apoptosis", "center nerve system" and "emergency diseases" in combination, limited in English version.STUDY SELECTION: By initial checking,the papers on caspase-3 in molecular biology and randomized control experiments on caspase-3 and the disorders in center nerve system were collected.DATA EXTRACTION: Totally 156 papers were collected directly related to caspase-3 and center nerve system, of which, 25 papers were in conformity with the criteria and 131 papers were exuded because of repeated contents and indirect relation with this paper.DATA SYNTHESIS: To synthesize the relevant information from the retrieved papers and sum up that the activity of caspase-3 is increased after acute cerebral injury, acute spinal injury, cerebral ischemia and cerebral hemorrhage and broadspectrum caspase-3 inhibitor, Z-VAD-fmk can reduce significantly the activity of caspase-3.CONCLUSION: Caspase-3 is the most important protease in cell apoptosis, it is the component in downstream effect of coordination of various apoptotic approaches and is the only way in protease cascade of cell apoptosis. The activated caspase-3 can split the essential and protective enzymes in cell and result in the alternations of apeptosis in morphology and biochemistry. DNA segmentation is the important biochemical property of nerve cell apoptosis at early stage in acute cerebral injury and the formation of it is necessary.

AIM:To study the effects of different duration of sleep deprivation (SD) on neurogranin (Ng),protein kinase C (PKC) and Ca2+-calmodulin dependent protein kinase II (CaMK II) mRNA expressions in hippocampus and forebrain of rats. METHODS:Male Wistar rats were divided into three groups:24 h,48 h and 72 h experimental groups. Each group was divided into sleep deprivation group (SD group) and control group (C group). SD model was established by sleep deprivation box. One step methods by Trizol was used to extract hippocampus and forebrain neuronal total RNA. The changes of Ng,PKC and CaMK II mRNA expressions were detected by SYBRA green I RT-PCR. RESULTS:(1) The expression of Ng mRNA in hippocampus of SD group was significantly lower than that in C group after 24 h,48 h and 72 h SD (P

Juvenile myopia has become the most prominent issues to students' healthy growth in recent years,attracted widely concerns in the community.Evidence-based eye scientific research has shown that there is no method to cure myopia.Preventive treatment explores the unique effects of early interventions by providing patients with guidance on young people's daily life,diet and myopic prevention measures,which may effectively improve the incidence of juvenile myopia and has well social benefits.

Hepatocellular carcinoma(HCC)shows high malignancy and metastasis. Hepatitis B virus X protein (HBx), a virus protein coded by hepatitis B virus, plays an important role in HCC metastasis. Recently, it was reported that HBx activates metastatic signal-pathways through MMPs, VEGF, uPA etc.,and promotes metastasis of hepatocellular carcinoma.