miR-200c is a member of miR-200 family,and it plays an important role in tumor diagno-sis,metastasis and chemoresistance.miR-200c is identified as a molecular marker and prognostic indicator in cancer screening.It can inhibit epithelial-mesenchymal transition,tumor invasion and metastasis,and increase the chemosensitivity of tumor cells,but the relevant mechanism is still not fully clear.The studies of miR-200c and some factors in regulatory pathway are beneficial to promote its applications in clinical diagnosis.

Objective To analyze the risk factors of pulmonary embolism in patients with negative Ddimer in serum in order to determine the need of pulmonary computed tomography angiograph (CTA) to confirm the final diagnosis in those patients for avoidance of misdiagnosis.Methods A retrospective analysis of 106 patients suspected to suffer from pulmonary embolism (PE) with serum negative D-dimer checked with pulmonary CTA was carried out.According to the results of CTA, the patients were divided into two groups, namely PE group (n =41) and non-PE group (n =65).The difference in clinic presentation, the time elapsed from onset to visit, N-terminal pro-brain natriuretic peptide (NT-proBNP), high risk factors (such as immobilization for 3 weeks, leg swelling and pain to palpation, history of deep vein thrombosis, malignancy) and Wells score (≥ 4 points indicates probability of PE).And logistic regression analysis was made to investigate the risk factors in PE with negative D-dimer.Results The analysis study showed that 38.6％ of total patients suspected to suffer from PE with serum negative D-dimer were checked by CTA to confirm the presence of PE.One important characteristics of the D-dimer negative PE patients was the longer time consumed from onset to visit [(9.51 ±2.01) d vs.(4.01 ±1.92) d, P＜ 0.05], and majority of the CTA positive patients suspected to suffer from PE with negative D-dimer had high risks of PE (P ＜0.01).Compared with the non-PE group, the Wells score ≥4 points and the level of serum NT-proBNP significantly increased in the PE group (P ＜ 0.01).Logistic regression analysis revealed that dyspnea, high NT-proBNP level and Wells sore ≥ 4 points were risk factors for D-dimer negative PE.Conclusion Delayed treatment was the main cause of misdiagnosis of D-dimer negative PE.Dyspnea, high NT-proBNP level and Wells sore ≥4 points were risk factors for suspected PE patients with negative D-dimer, and these patients should be confirmed by pulmonary CTA.On the contrary, PE could be excluded if patients with D-dimer negative had no these risk factors.

Objective To investigate the level of serum procalcitonin (PCT) for exploring the clinical value in identifying microorganism strains in the intensive care unit (ICU) patients with blood stream infections.Methods A retrospective analysis of patients with positive blood culture of a single strain and with serum PCT levels detected simultaneously was carried out from January 2010 through December 2012.The comparisons of PCT levels were done among Gram-negative (G-) bacteria,Gram-positive (G +) bacteria and fungi in patients with bloodstream infections.The diagnostic performance of PCT was determined by the receiver operating characteristic curve (ROC).Results A total of 524 patients with blood stream infection were enrolled and categorized into three different groups,namely G-bacteria infection group (n =206),G + bacteria infection group (n =276),and fungi infection group (n =42).The median value of PCT level of G-bacteria group was 14.9 ng/ml,which was significantly higher than that of the other two groups with 0.14 ng/ml and 1.76 ng/ml,respectively (P ＜ 0.01).Further,the PCT level of fungi group also obviously higher than that of G + bacteria group (P ＜ 0.001).According to ROC,PCT level at 2.11 ng/ml could distinguish G-bacteria infection from G + bacteria infection with sensitivity 82.8％ and specificity 80.1％,while PCT at 5.09 ng/ml was used to distinguish G-bacteria infection from fungi infection with sensitivity 68％ and specificity 73.8％.The area under the ROC of G + bacteria and fungi was 33.0％ (P ＜ O.01).Conclusions Serum PCT level is valid for distinguishing ICU patients with blood stream infection caused by G-bacteria from G+ bacteria or from fungi,but the validity of PCT for distinguishing G + bacteria from fungi infection needs to be set up by further studies.

The production technology for the first generation of biofuels has been made great achievements and some countries, such as USA, EU countries, and Brazil, have formed successful biofuel industrial chains. Cellulose ethanol, a representative of the second generation of biofuels and a kind of more promising alternative fuels, has not yet got enough key technological breakthroughs and its large scale commercial production still needs rather some time to realize. Now it is in the early stage of transition to the second generation of biofuels. Taking the development of second generation of biofuels as their national policies, many countries have developed long-term development plans and objectives, and provided a good policy environment and strong support for it. Thus institutes and enterprises are engaging and successing in addressing key issues relating to the development of biofuels. At the mean time, some important issues relating to the sustainable development of biofuels have attracted people's attention.

Biomass resources are strategically vital for the sustainable development of a country.The United States has recently made a variety of plans or roadmaps and taken significant actions in order to promote the R&D of biomass resources.These plans and actions for the key issues in the development of biomass resources were analysed.

Objective To construct an expression system to produce the virus-like particles containing a part of the sequence of PSA mRNA, which are ribonuclease-resistant due to the encapsulation of the mRNA by bacteriophage MS2 coat proteins. Methods The PCR products of PSA cDNA fragments were cloned to TA vector pBS-T, then the targeted segments could be obtained when the pBS-T-PSA were digested by restriction endonuclease Hind Ⅲ and cloned to prokaryocytic expression vector pNCCL1. The recombinant plasmids named PNCCL1-PSA were transfected into E. Coli BL21-DE3 and induced to express with IPTG. Results The recombinant plasmids were successfully constructed. The bacteriophage MS2 coat protein which expressed in BL21 can self- assemble to form ribonuclease resistant virus-like particles and the PSA mRNA was encapsulated into virus-like particles. Conclusions The virus-like particle containing PSA mRNA can be expressed in prokaryocyte and it can be used as standard and control in detecting PSA mRNA. It provides a new, stable and ribonuclease-resistant RNA standard in RNA detection.

Objective To determine the likelihood of G-protein coupled receptor 56 (GPR56 ) induces axonal development and myelination in the corpus callosum of mouse brain.Methods A total of 64 Gpr56 +/-and Gpr56 -/-mice were selected and randomly divided into two groups:Gpr56 +/-group (n=32)and Gpr56 -/-group (n=32).According to number of days after birth,each group was further divided into 4 subgroups including P7d,P14d,P21d and P28d subgroups.Levels of neurofilament-200 (NF -200)and proteolipid protein (PLP ) of myelin basic protein in corpus callosum were measured with immunohistochemistry staining and Western blot in P7d、P14d、P21d、P28d Gpr56 +/- and Gpr56 -/-mice.Gpr56 +/-and Gpr56 -/-neurons were cultured using P1 d Gpr56 +/-and Gpr56 -/-mouse brain.The lengths of Gpr56 +/- and Gpr56 -/-neuronal axon were measured and compared with Image J software. Axonal myelination in the corpus callosum of mouse brain in each group was observed under electronic microscopy and the axonal diameters between subgroups were compared.Results The levels of NF-200 and PLP in the corpus callosum in P7d、P14d、P21d、P28d Gpr56 -/-mice decreased significantly compared with Gpr56 +/- mice.The length of Gpr56 -/-neuronal axon was shortened compared with Gpr56 +/-neuronal axon.The number of myelinated axons was obviously reduced in the corpus callosum in P28d Gpr56 -/-mice.The diameter of axon in the corpus callosum of P28d Gpr56 +/-mouse is longer than that of P28d Gpr56 -/-mouse. Conclusions GPR56 may be involved in axonal development and myelination in the corpus callosum of mouse brain.

Objective To analyze the gene mutation and clinical characteristics of BRCA 1/2 by high resolution melting curve ( HRM ) in breast cancer patients and high risk groups , and to discuss the application value for BRCA 1/2 mutation detection by using HRM curve analysis in people at high risk of breast cancer.Method The clinical control analysis was used ,Peripheral blood samples of 52breast cancer patients,their first-degree relatives (52 cases consisting of high risk group ) and 40 healthy people without family history of breast cancer cases were collected from Anhui Province Tumor Hospital or Bozhou People ′s Hospital during March 2015 to June 2016.To establish an effective method for BRCA 1/2 mutation detection by using HRM curve, and the mutation positive results were validated by gene sequencing .To analyze the correlation between the of BRCA 1/2 gene mutation and the risk factors , a logistic method was used .Results 9 cases of BRCA1/2 gene mutations were found in 52cases of breast cancer patients and the mutation rate was 17.3%.5 cases of BRCA1/2 gene mutations were found in 52 cases of breast cancer high risk groups and the mutation rate was 9.6%.In 40 healthy people who without family history of breast cancer cases ,we found only 1 gene mutation case.All the mutation positive results detected by HRM curve analysis were matched with gene sequencing results .BRCA1/2 gene mutations and the risk factors such as primiparous age and chronic mammary gland disease have a certain correlation .In the 9 cases of BRCA1/2 gene mutations , we found 5 cases of BRCA1/2 gene mutations in their first-degree relatives, with the consistency of 44.4%(4/9).Conclusion Thebreast cancer patients′s first-degree relatives have a high mutation rates on BRCA1/2 gene and they can be the key screening objects .HRM curve analysis can be used in health screening and risk assessment at the breast cancerhigh risk groups .

Objective To investigate the feasibility of self‐control materials serum thyroid hormone detected in the clinical labo‐ratory internal quality control in applications .Methods The serum thyroid hormone test results in patients with high‐value ,the ser‐um was mixed with a certain proportion of the healthy population ,dubbed serum control materials ,after aliquots -20 ℃ .Every o‐riginal supporting quality control and simultaneous detection of free thyroxine (FT4) ,three free triiodothyronine (FT3) ,thyroid stimulating hormone (TSH) ,thyroglobulin (TG) ,thyroid‐microglobulin antibody (TMA) ,thyroglobulin antibodies (TGA) and other thyroid hormone six items detected before the appearance of control samples was observed continuously detected six months to observe stability ;used EXCELL do J‐L maps ,statistical mean of each project within six months ,CV and uncontrolled number of observed values in the internal quality control applications .Results Within 6 months after the product was frozen homemade quali‐ty control serum soluble appearance clear and transparent ,no precipitation and turbidity ;1 ,3 ,6 ,10 ,15 ,30 ,45 ,60 ,90 ,120 day of the first magnitude and no significant changes in thyroid hormone ;compared with the original quality control materials ,low CV values . In the six months internal quality control applications ,the cumulative results of each project without 1 ,3 ,6‐month and six months significantly different ;project and six months mean cumulative comparison between the mean drift or change in trend did not ap‐pear ;items and cumulative CV were in control of the allowable range (CV <1/3 times within total variation );6 months of internal quality control work ,runaway alarm :13s ,2 times ,22s ,1 times ,R4s ,1 times .Conclusion Serum thyroid hormone homemade frozen control samples have better stability ,and can replace its import control materials ;internal quality control in their daily activities , through EXCELL test results for J‐L diagram precision can find instability timely corrective treatment to ensure that thyroid func‐tion test results are reliable ,worthy of clinical application .

Objective To explore the value of echo-tracking technique in the detecting the ipsilateral external iliac artery elasticity after gunshot wound in pig limbs.Methods Two-dimensional ultrasound imagings and elasticity parameters of external iliac artery of fifteen pig limbs were obtained respectively,and the results were compared with pre-injury groups.The animals were sacrificed after ultrasonography.Pathological examinations of adjacent external iliac artery of injured pig limbs were analyzed.Results Two-dimensional ultrasound imagings of external iliac arteries had no significant changes post-injury.The changes of elasticity parameters were significiant differences in the injured group comparing with the pre-injured group (P ＜0.05),including the increased stiffness parameter(β),pressure-strain elasticity modulus (Ep)and the decreased arterial compliance(AC).Pathological result showed that the internal elastic lamina of artery detected were flat,endothelial cells came off discontinuously and structure of them were undefined.Conclusions Echo-tracking technique can find the elastic changes of adjacent artery indirect injured by gunshot wound sensitively and which can suggest the occurrence of vascular indirect injury.