Objectives This study was conducted to detect and analyze the presence of plasmidmediated quinolone resistance (PMQR) determinants [qnr,aac-(6′)-Ib-cr and qepA] among clinical isolates of Citrobacter freundii strains isolated from patients in Anhui,China,and to understand the susceptibility of PMQR positive strains to commonly used antimicrobial agents.Methods During the year 2009,31 Citrobacter strains were collected from the First Affiliated Hospital of Anhui Medical University.Polymerase chain reaction (PCR) was used to detect PMQR genes.Amplicons were purified,sequenced and compared with data from the GenBank.Conjugation experiments were conducted to determine whether the qnr-carrying plasmids were self-transferable.The susceptibility of the positive isolates and transconjugants were tested by agar dilution method according to Clinical and Laboratory Standards Institute (CLSI) guidelines.The minimum inhibitory concentrations (MIC) of ciprofloxacin and levofloxacin were determined by E-test strips.Results Among the 31 Citrobacter strains,the qnr genes were detected in 8 isolates (25.8％),among which,6 carried qnrB.Aac-(6′)-Ib-cr and qepA were not identified in these isolates.The qnr genes were transferred from four clinical isolates to their transconjugants.Sequence analysis identified one novel qnrB variant (qnrB24).The resistant rate of qnr-positive clinical isolates to quinolone was 87.5 ％.Most of them were also resistant to various other antibiotics,including cefotaxime (75.0 ％),amikacin (7.5 ％),ceftazidime (62.5 ％),cefapime (37.5 ％),and gentamycin (87.5 ％).All qnr positive strains were susceptible to imipenem.MIC of all transconjugants showed reduced susceptibility to fluoroquinolones,with MIC increased by 10-23 folds.Conclusions Our study shows that qnr gene has occurred in Citrobacter freundii isolates from Anhui Province,China.QnrB is most prevalent in these isolates.Most qnr positive isolates are resistant to commonly used antimicrobial agents.

Xuzhou Medical Collage developed a set of test result analysis software.It uses Visual Basic for Application(VBA)and statistics function in database Excel2000.It is simple to use and powerful in function.A brief introduction was given below to help you to use it.

To investigate molecular epidemiology of DuCV in Cherry Valley ducks in China,the complete genomes of six DuCV strains,which were detected from Cherry Valley ducks in China between 2007 and 2008,were sequenced.Sequence and phylogenetic analysis were carried out to compare these six strains with another 27DuCV strains from Mulard duck,Muscovy duck,Pekin ducks and Mule duck.The analysis showed that the six DuCV strains exhibited typical genetic features of the family of DuCV,such as a stem-loop structure,three major open reading frames (Rep,Cap and ORF3),four intergenic repeats and the conserved motifs for rolling circle replication and for the dNTP binding domain located in the Rep protein.Phylogenetic analysis of the nucleotide sequences of the complete genome and Cap gene of these strains together with those that have been previously published demonstrated two distinct DuCV genotypes.The DuCV strains with complete genomes containing 1988and 1989 nucleotides clustered in genotype A,whereas the strains with complete genomes containing 1991,1992,1995 and 1996 nucleotides lay in genotype B.The six DuCV strains from Cherry Valley ducks were divided into the two groups.The results of the study provides some insight into the variation of DuCVs in Cherry Valley ducks.

With thousands of sequenced 16 S rRNA genes available,and advancements in oligonucleotide microarray technology,the detection of microorganisms in microbial communities consisting of hundreds of species may be possible.The existing algorithms developed for sequence-specific probe design are not suitable for applications in large-scale bacteria detection due to the lack of coverage,flexibility and efficiency.Many other strategies developed for group-specific probe design focus on how to find a unique group-specific probe that can specifically detect all target sequences of a group.Unique group-specific probe for each group can not always be found.Hence,it is necessary to design non-unique probes.Each probe can specifically detect target sequences of a different subgroup.Combination of multiple probes can achieve higher coverage.However,it is a time-consuming task to evaluate all possible combinations.A feasible algorithm using relative entropy and genetic algorithm (GA) to design group-specific non-unique probes was presented.

Objective:To study the anatomical correlation between dental arch and the volume of upper airway in patients with obstruc-tive sleep apnea hypoventilation syndrome(OSAHS). Methods: Dental arch architecture and upper airway volume were measured by cone beam CT(CBCT) in the subjects with OSAHS(n=22) and without OSAHS(n=19). The correlation between dental arch and the supper airway volume in OSAHS patients was analyzed. Results:The length of the upper dental arch and the height of palate in OSAHS patients were larger than those of the controls(All, P<0. 05). Cross-sectional area of nasopharynx and retropalatal and the total volume of upper airway were negatively correlated with the palatal height and upper dental arch length(P<0. 05), while positively correlated with upper dental arch of molar regions(P<0. 05). Conclusion:The abnormal shape of upper dental arch is related to the airway vol-ume of nasopharynx and retropalatal region in patients with OSAHS.

Objective To investigate the effect of Exosomes derived from lung cancer cells on the migration of secretory cells and homologous tumor cells and to explore the role of PI3K/Akt and SRC signaling pathways in this process.Methods Exosomes were isolated from the supematant post density gradient centrifugation of A549,lung cancer cells.Morphology of the Exosomes was studied using transmission electron microscopy.Protein expression was analyzed using Western blotting.Cell migration was analyzed by a transwell assay.Results The double-membrane-bound Exosomes appeared as discal-shaped structures,30-100 nm in diameter.Western blotting showed that CD9 was abundant in the Exosomes.The Exosomes promoted the migration of A549 cells and their homologous tumor cells,HCC827 in a dose-dependent manner,accompanied by the activation of Akt and SRC.Conclusion The Exosomes derived from A549 (lung cancer) cells promote the migration of the secreting cells and the homologous tumor cells.The mechanism may be correlated with the activation of Akt and SRC.

Objective To explore the effect of Exosomes isolated from the A549 lung cancer cells on the proliferation of these cells and their ho?mologous tumor cells,HCC827,and the role of the PI3K/Akt and SRC signaling pathways in this process. Methods Exosomes were isolated from the supernatant after density gradient centrifugation of A549 cells. The Exosomes morphology was observed by transmission electron microscopy. The expression of the Exosome?specific proteins was analyzed using Western blotting. Cell proliferation was investigated using the MTT assay. Re?sults The A549?derived Exosomes were 30?100 nm in diameter and had a bilayer membrane.Western blotting showed that CD9 was detected in these Exosomes. The isolated Exosomes promoted the proliferation of the A549 and the HCC827 cells in a dose?and time?dependent manner,ac?companied by the activation of Akt and SRC. Conclusion Exosomes isolated from A549 cells promote the proliferation of the secreting cells and the homologous tumor cells in a dose?and time?dependent manner. The mechanism may be related to the activation of Akt and SRC.

OBJECTIVE: Through a retrospective large sample analysis of copy number variants in single center, we explored the technical standards for the interpretation and reporting of constitutional copy-number variants (CNVs) jointly proposed by the American College of Medical Genetics and Genomics (ACMG) and the Clinical Genome Resource (ClinGen) in 2019, analyzing its impact on CNVs ratings and the improvement in the consistency of the classification of CNVs in clinical laboratories. METHODS: 236 CNVs that assessed as pathogenic, uncertain significant (including likely pathogenic, uncertain and likely benign) by the 2011 ACMG guidelines between August 2018 and December 2019 in our center were re-analyzed. Four working group members of the center reclassified and evaluated 235 CNVs according to 2019 ACMG guidelines. RESULTS: The consistency of clinical significance classification of CNVs was 91% and the α test coefficient was 0.98 among four working group members. Compared with the 2011 and 2019 ACMG technical standards for the CNVs classification, evaluation of pathogenicity and uncertain significant is basically consistent. 90% (45/50) of likely pathogenic and likely benign CNVs were Re-evaluated as variants of uncertain significance, and the difference is significant. CONCLUSION The new version ACMG/ClinGen guidelines for the evaluation of CNVs developed semi-quantitative point-based scoring system and help to improve the consistency in clinical classifications. It can also make the interpretation of CNVs more standardized and transparent.
DNA Copy Number Variations ; Genetic Testing ; Genetic Variation ; Genome, Human ; Humans ; Mutation ; Retrospective Studies

Objective:To construct the evaluation index system of lumbar puncture teaching for medical students, aiming to create a scientific assessment and evaluation method covering theoretical knowledge, skill practice, and professional accomplishment, so as to comprehensively evaluate the teaching effect of lumbar puncture for medical students, and improve the practical ability of clinical skills of medical students more effectively.Methods:The evaluation index scheme of lumbar puncture teaching for medical students was initially formulated through literature review and group discussion, and 20 experts related to clinical front-line work and medicine were invited to revise the scheme by applying Delphi expert consultation and applying analytic hierarchy process to quantify the entries and establish the final index weights at all levels.Results:The valid recovery rate of both rounds of expert consultation questionnaires in this study was 100%. The second round of expert consultation was conducted without changing experts, with an authority factor of 0.88. Kendall's coefficient of harmony was 0.136 and 0.184, respectively. After two rounds of expert consultation, the evaluation index system of lumbar puncture teaching for medical students, including 3 primary indicators (theoretical knowledge, comprehensive clinical ability and professionalism), 7 secondary indicators and 22 tertiary indicators, was initially constructed.Conclusion:The evaluation index system of lumbar puncture teaching for medical students constructed in this study is scientific and credible, which can provide quantitative basis for the training and assessment of medical students, and is of great theoretical and practical significance.

Objective: To evaluate the value of super microvascular imaging(SMI) for evaluating the effect of interventional therapy of liver cancer. Methods: A total of 30 patients with 40 leisions were enrolled in this study, from the tumor intervention department in the third affiliated hospital of suzhou university.This patients were underwent TACE, after the treatment 1 month, CDFI, SMI, and CT were study respectively. Using the continuity correction McNemar matching chi-square test, with P < 0.05 for the standard , CDFI and SMI shows the difference in monitoring the microvascular imaging in and around the tumors leisions. Results: A total of 30 patients, 12 cases were primary liver cancer (7 cases combined with liver cirrhosis), 18cases were metastatic liver cancer; 30 cases including 25 single and 5 multiple. Significant difference were found between CT and SMI in detecting blood flows inside the lesion (χ² = 8.642 9, P < 0.05), and were also found between CT and CDFI in detecting blood flows inside the lesion (χ² = 16.961 5, P < 0.05). The AUROC, sensitivity, specificity, accuracy, PPV and NPV of CDFI were 0.647, 29.4%、100%、29.4%、100%、20.0%, while in SMI were 0.809, 61.8%、100%、61.7%、100%、31.5%, respectively. Conclusions SMI SMI can detect the microvascular inside the lesions. This new method was superior to CDFI, achieving the same effect as CT.