This study aims to understand the epidemic distribution characteristics,antimicrobial resistance,virulence genes,and biofilm adhesion ability of Enterococcus in yaks on the Tibetan plateau.Three hundred and forty-six fresh yak fecal samples and 311 milk samples were collected from four provinces on the Tibetan plateau(Xizang,Sichuan,Gansu,Qinghai),totaling 657 sam-ples.Bacterial isolation and identification were conducted,followed by 16S rDNA gene detection and the construction of a systematic evolutionary tree.The isolated strains were tested for antimi-crobial resistance and virulence genes using PCR,and sensitivity tests were performed using 18 types of antibiotics.The biofilm adhesion ability of the isolated bacteria was determined using an improved semi-quantitative crystal violet staining method.The results showed that the total isola-tion rate of Enterococcus was 32.27％,with Sichuan having the highest at 60.23％,followed by Gansu,Qinghai,and Tibet autonomous region at 42.70％,23.47％,and 18.31％respectively.In terms of sample types,the isolation rate in fecal samples was 36.71％,and in milk samples,it was 27.33％.Through PCR amplification,bands of approximately 1 400 bp were obtained,and 5 strains were selected for evolutionary analysis,forming a separate cluster.Among the 212 isolated strains,a high resistance to clindamycin,quinupristin-dalfopristin,linezolid,levofloxacin,and erythromycin was observed,with various resistance phenomena,accounting for 60.85％.Only 5 out of 12 resist-ant genes were detected,namely erm(B),tet(L),tet(O),tet(M),and ant(6)-Ia.All 13 virulence genes were detected in Enterococcus,with detection rates in the range of 5.19％to 95.76％,where cpd was 95.75％,gelE was 91.98％,efaA was 86.79％,asal was 86.32％,and the rest ranged from 5.19％to 55.66％.The fsr virulence gene was not detected in Enterococcus from milk sources.Among the isolated strains,3.30％showed medium adhesive ability,48.58％showed weak adhesive ability,and 48.11％showed no adhesive ability.The above research revealed the preva-lence of yak derived Enterococcus,the carrying status of resistance and virulence genes,and the correlation between biofilm phenotypes,laying the foundation for mastering research data on yak-derived Enterococcus in the Tibetan plateau.

This study aims to understand the epidemic distribution characteristics,antimicrobial resistance,virulence genes,and biofilm adhesion ability of Enterococcus in yaks on the Tibetan plateau.Three hundred and forty-six fresh yak fecal samples and 311 milk samples were collected from four provinces on the Tibetan plateau(Xizang,Sichuan,Gansu,Qinghai),totaling 657 sam-ples.Bacterial isolation and identification were conducted,followed by 16S rDNA gene detection and the construction of a systematic evolutionary tree.The isolated strains were tested for antimi-crobial resistance and virulence genes using PCR,and sensitivity tests were performed using 18 types of antibiotics.The biofilm adhesion ability of the isolated bacteria was determined using an improved semi-quantitative crystal violet staining method.The results showed that the total isola-tion rate of Enterococcus was 32.27％,with Sichuan having the highest at 60.23％,followed by Gansu,Qinghai,and Tibet autonomous region at 42.70％,23.47％,and 18.31％respectively.In terms of sample types,the isolation rate in fecal samples was 36.71％,and in milk samples,it was 27.33％.Through PCR amplification,bands of approximately 1 400 bp were obtained,and 5 strains were selected for evolutionary analysis,forming a separate cluster.Among the 212 isolated strains,a high resistance to clindamycin,quinupristin-dalfopristin,linezolid,levofloxacin,and erythromycin was observed,with various resistance phenomena,accounting for 60.85％.Only 5 out of 12 resist-ant genes were detected,namely erm(B),tet(L),tet(O),tet(M),and ant(6)-Ia.All 13 virulence genes were detected in Enterococcus,with detection rates in the range of 5.19％to 95.76％,where cpd was 95.75％,gelE was 91.98％,efaA was 86.79％,asal was 86.32％,and the rest ranged from 5.19％to 55.66％.The fsr virulence gene was not detected in Enterococcus from milk sources.Among the isolated strains,3.30％showed medium adhesive ability,48.58％showed weak adhesive ability,and 48.11％showed no adhesive ability.The above research revealed the preva-lence of yak derived Enterococcus,the carrying status of resistance and virulence genes,and the correlation between biofilm phenotypes,laying the foundation for mastering research data on yak-derived Enterococcus in the Tibetan plateau.

OBJECTIVETo use next generation sequencing (NGS) to identify unknown abnormality of chromosome 9 in a fetus and explore its mechanism.

METHODSA pregnant woman with abnormal fetal ultrasound finding underwent amniocentesis for G-banded chromosomal analysis. Karyotyping was also performed on peripheral blood samples derived from its parents. Fetal blood sample was obtained for NGS testing to identify abnormality unrecognized by karyotyping.

RESULTSAnalysis of amniocytes has revealed a 46,XX,der(9)(?::p21 to qter) karyotype, while both parents had a normal karyotype. NGS analysis of the fetus revealed a 20.67 Mb duplication (4 454 279-25 126 275) at 9p21.3p24.2, which overlapped with that of the 9p duplication syndrome, and a 4.43 Mb deletion at 9p24.2p24.3 (10 001-4 442 364), which partially overlapped with that of 9p deletion syndrome and 46,XY sex reversal 4 region. Comparison of the sequencing data with reference genome database indicated direct duplication of 9p21.3p24.2, which was also supported by review of the morphology of chromosome 9p. Therefore, the karyotype of the fetus was verified to be 46,XX,der(9) dir dup(9)(p21.3p24.2), del(9)(p24.2p24.3).

CONCLUSIONCombined G-banded karyotyping and NGS can identify dir dup del(9p) with accuracy. Delineation of the mechanism of dir dup del(9p) and its genotype-phenotype correlation may facilitate genetic counseling and estimation of recurrence risk.

Adult ; Chromosome Banding ; Chromosome Deletion ; Chromosomes, Human, Pair 9 ; genetics ; Female ; Fetal Diseases ; diagnosis ; genetics ; Humans ; Male ; Pregnancy ; Prenatal Diagnosis ; Trisomy ; genetics

BACKGROUND:Numerous studies have confirmed that neovascularization plays an important role in the growth, invasion and metastasis of tumors. OBJECTIVE:To investigate the features of CD133+ ovarian cancer stem-like cels differentiating into vascular endothelial cels. METHODS:CD133+ ovarian cancer stem-like cels were successfuly harvested from A2780 ovarian cancer cel lines using serum-free culture method, and incubatedin vitro onto 96-wel plates with or without Matrigel. Then, we observed the capacity of CD133+ ovarian cancer stem-like cels and human umbilical vein endothelial cels to form tube-like structures at different time points. Through xenograft experiments, the role of CD133+ ovarian cancer stem-like cels in the angiogenesis of ovarian cancer was observed using immunofluorescence staining. RESULTS AND CONCLUSION:CD133+ovarian cancer stem-like cels and human umbilical vein endothelial cels cultured with no Matrigel had no corresponding lumen formation, and could not express CD31. But those cultured with Matrigel had lumen formation and expressed CD31 significantly. After tumor formation, human-derived CD31 expression was observed in the tumors. These findings indicate that CD133+ ovarian cancer stem-like cels can differentiate into vascular endothelial cels, and be involved in tumor revascularization.