The cholesterol esterase and its oxidase were respectively immobilized onto sol-gel(tetraethyl orthosilicate)and then an enzymatic reaction column was prepared. Hydrolysis of cholesterol ester took place in the presence of cholesterol esterase to form cholesterol under catalysis of cholesterol oxidase, and Cholesterol was oxidized to produce hydrogen peroxide which reacted with luminal in the presence of simulated enzyme hemoglobin to result in the emission of light. Thereupon, a chemiluminescence system combined with flow injection technology by sol-gel immobilized enzyme was developed for the determination of cholesterol including free and total amount in human serum. The CL intensity was well linear with the concentration of cholesterol;liner range of total and free cholesterol was 1.01×10~(-6)～2.02×10~(-4) mol/L with a detection limit of 7.5×10~(-7) mol/L) and 5.0×10~(-8)～2.18×10~(-5) mol/L) with a detection limit of 5.0×10~(-9) mol/L respectively. Contrasted the method) with the biochemical analyzer (TBA-120FR), both the methods had no significant difference. This method has been successfully applied for the detection of cholesterol in clinic serum samples.

Objective To observe the characteristics of vertical cast-off bloodstain pattern by different hitting-tools. Methods The regular hitting tools, a kitchen knife, a dirk, a plane set-hammer and an iron pipe, were selected. At a distance of 30 cmaway fromthe wall, the hitting tool with 5 mL fresh chick-en blood made the cast-off bloodstain fromtop to bottom. Then the holistic distribution characteristics ( length , width and density ) of cast-off bloodstain and morphology characteristics ( length , width and contact angle) of first single cast-off bloodstain were analyzed. Results The distribution length of cast-off bloodstain formed by dirk was minimum( P<0 .05 ) . The distribution width of cast-off bloodstain formed by kitchen knife was minimum(P<0.05). Except the pair of kitchen knife and plane set-hammer, the distribution density between each two tools had statistical differences (P<0.05). The length of first single cast-off bloodstain formed by plane set-hammer was longest compared (P<0.05). The width of first single cast-off bloodstain had statistical differences between kitchen knife and plane set-hammer, and between dirk and plane set-hammer (P<0.05). Conclusion The type of hitting tool could be inferred by the specific characteristics of cast-off bloodstain pattern formed by every specific type of hitting tool in crime scene.

Objective To analyze the variations of glycerol-3-phosphate dehydrogenase 1 like gene (GPD1-L) and address the association with sudden m anhood death syndrom e (SMDS). Methods The genom ic DNA was extracted from blood sam ples of the SMDS group and the norm alcontrolgroup.The exons, exon-in-tron boundaries and 3′-U TRs of coding region of GPD1-L w ere PCRam plified and DNAsequenced di-rectly to confirm the types of variations. The genotype frequency and allele frequency w ere analyzed statistically. Results There w ere tw ovariants in the SMDS group, c.465C>Tand c.*18G>T, the latter existed certain degree difference of genotype distribution and allele frequency betw een the SMDS group and the control group, but there was no statistically significant (P>0.05). Conclusion The relation be-tw een gene m utation of GPD1-L and the occurrence of Chinese SMDS deserves a further research.

Gastrointestinal stromal tumors (GISTs) are derived from non-directed differentiation of gastrointestinal mesenchymal tissue, which lack of typical clinical symptoms, and many asymptomatic GISTs are often found on physical examination. The tumor is primarily through implantation metastasis and blood metastasis. Currently, conventional medical imaging methods, such as X-ray barium meal, US, CT, MRI, PET/CT and ES, are still the main means of diagnosis of GISTs. Early diagnosis and early treatment are key factors of the prognosis in GISTs. Therefore, we need to be proficient in various medical imaging methods, then apply them to the diagnosis of GISTs, and to provide comprehensive and valuable information for clinical practice. Through retrieving and consulting literature of medical imaging associated with GISTs, this paper reviews the current status and progress of medical imaging in diagnosis of GISTs.
Gastrointestinal Neoplasms ; Gastrointestinal Stromal Tumors ; Humans ; Magnetic Resonance Imaging ; Prognosis

Background Gastric carcinogenesis is a multifactorial and complex process, in which long non-coding RNAs (lncRNAs) play important roles as oncogenes or antioncogenes. Research has found that the expression of lncRNA LINC02859 is down-regulated in gastric cancer tissues and correlated with the degree of tumor differentiation and TNM stage, and also plays an important role in the development of malignant transformation of cells induced by environmental carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), but its mechanism of action is still unclear. Objective To explore the role and potential regulatory mechanism of gastric cancer-associated lncRNA LINC02859 in MNNG-induced malignant transformation of human normal gastric mucosal cells (GES-1). Methods A total of 110 gastric cancer patients from a high incidence area of gastric cancer in Gansu Province were selected, and their cancer tissues and normal gastric mucosa tissues adjacent to the cancer were collected to detect the expression level of LINC02859 by real-time quantitative PCR (RT-qPCR). High-throughput sequencing and bioinformatics analysis of the tissues were used to identify the potential signaling pathways regulated by the genes co-expressed with LINC02859. GES-1 cells at 70%-80% cell fusion with low cell passage number and normal morphology were incubated with 0, 0.25 and 0.5 μmol·L⁻¹ MNNG solution for 48 h and the LINC02859 expression level was detected. Cell proliferation activity was detected by Cell Counting Kit-8 (CCK-8), clone formation was detected by plate clone formation assay, and cell migration ability was detected by scratch assay to evaluate the effects of MNNG on cell morphology and function. The expression levels of key proteins of Wnt signaling pathway were detected by RT-qPCR and Western blotting. Results The RT-qPCR results showed that LINC02859 was lowly expressed in the gastric cancer tissues compared with the paracancerous tissues, and the difference was statistically significant (P < 0.05). The pathway enrichment analysis showed that LINC02859 potentially regulated the Wnt pathway. The in vitro malignant transformation assay suggested that after the MNNG exposure, the malignant cells of passage 5 (MC-5) had altered morphology, increased number of colony formation, and higher proliferation and migration ability than the control cells; compared with the normal GES-1 cells, LINC02859 gene expression levels were reduced in the 0.25 μmol·L⁻¹ and the 0.5 μmol·L⁻¹ MNNG-exposed GES-1 cells; the expression levels of key proteins of the Wnt pathway, transcription factor 7 (TCF7), Axis inhibitor (Axin1), phosphorylation of glycogen synthase kinase-3 beta (p-GSK-3β), casein kinase 1 (CK1), and β-catenin, were elevated in the cells after 0.5 μmol·L⁻¹ MNNG exposure (P < 0.05); whereas, overexpression of LINC02859 suppressed the activating effect of MNNG on the Wnt pathway. Conclusion LINC02859 is lowly expressed in the cancer tissues of gastric cancer patients. MNNG exposure induces morphological and functional changes in GES-1 cells, down-regulated expression of LINC02859, and activation of the Wnt signaling pathway; overexpression of LINC02859 inhibits the activation of the Wnt signaling pathway in the gastric carcinogenesis induced by MNNG exposure.