The tumorigenesis of breast cancer is a multistep process with many factors.The microRNAs (miRNA) participates in the development and distance metastasis of tumor by regulating proliferation,apoptosis and migration of tumor cells.The study of the mechanisms that miRNA impacting breast cancer cell proliferation and metastasis may provide new ideas for the diagnosis and treatment of breast cancer.

OBJECTIVETo investigate the risk factors for congenital external malformation.

METHODSA 1:2 matched case-control study was conducted with 52 cases of congenital external malformation during perinantal period collected from surveillance in Baoan District of Shenzhen City from January to June in 2000.

RESULTSSimple and multiple conditional logistic regression analysis showed that the major risk factors for congenital external malformations during perinatal period were preterm labor (beta(k) = 1.4171, s(theta, beta(kappa)) = 0.4601, OR = 4.115), adverse mental stimulus (beta(kappa) = 2.1870, s(theta beta(kappa)) = 0.7873, OR = 8.909), taking medicine (beta(k) = 1.9178, s(theta beta(kappa)) = 0.8072, OR = 6.808) and exposure to hazardous chemicals during early pregnancy (beta(k) = 0.9602, s(theta beta(kappa)) = 0.4262, OR = 2.612).

CONCLUSIONSCongenital external malformation during perinatal period was caused by multiple risk factors and results of the study showed that environmental and mental factors were in obvious connection with its occurrence.

Case-Control Studies ; Congenital Abnormalities ; etiology ; Female ; Humans ; Male ; Multivariate Analysis ; Perinatal Care ; Pregnancy ; Risk Factors

Objective:To confirm the Sigma N transcription factor activity of a gene product encoded by LA2404 gene of Leptospira interrogans ( L. interrogans) and to identify the target genes of Sigma N signaling system. Methods:L. interrogans LA2404 gene and its regulated target genes were predicted using bioinformatic analysis according to the promoter sequence signature in Sigma N-regulated genes. A LA2404 gene-knockout (ΔLA2404) strain of L. interrogans was constructed based on homologous sequence recombinant of suicide plasmid. Real-time fluorescent quantitative RT-PCR (qRT-PCR) was used to detect the changes in the expression of target genes at mRNA level in the ΔLA2404 mutant. A prokaryotic expression system for LA2404 gene was established and the target recombinant protein rSigma N was extracted by Ni-NTA affinity chromatography. Gel electrophoresis mobility shift assay (EMSA) was used to screen out the target genes regulated by rSigma N. Results:Pathogenic L. interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai carried one Sigma N gene and 22 Sigma N promoter sequence-containing target genes. Qualitative examination of the ΔLA2404 mutant by microscopy revealed no defect in motility and appearance. Expression of LA1188, LA2306, LA3426, LA1968, LA1313, LA3806 and LA0773 genes at mRNA level in the ΔLA2404 mutant was significantly down-regulated ( P<0.05), but no significant changes in the expression of other target genes at mRNA level were detected. EMSA results confirmed that rSigma N could bind to the promotor sequences of the target genes mentioned above. Conclusions:Sigma N transcription factor was encoded by LA2404 gene. LA1188, LA2306, LA3426, LA1968, LA1313, LA3806 and LA0773 genes contained Sigma N promoter sequence and the expression of them was regulated by Sigma N signaling system.

ObjectiveTo analyze the genetic characteristics of the hemagglutinin （H） gene of measles virus （MeV） in Shanghai， 2001‒2018. MethodsNasopharyngeal swab specimens were collected from suspected measles cases reported in Shanghai from 2001 to 2018， and the isolation of measles virus was conducted with Vero/hSLAM cell line. RT-PCR amplification and sequencing were conducted after RNA extraction to analyze the genetic characteristics of the complete H gene. ResultsIn total， 5 665 nasopharyngeal swab samples were collected by suspected measles case surveillance from 2001 to 2018， and 1 394 measles virus strains were isolated. The homology of nucleotide acid and amino acid among 349 representative measles virus isolates was 87.4%‒100.0% and 85.1%‒100.0%， respectively. The homology of nucleotide acid and amino acid between representative measles virus isolates and China vaccine strain （S191） was 85.7%‒100.0% and 84.1%‒100.0%， respectively. All the sub-genotype H1a MeV isolates had an amino acid substitution （Ser240Asn）， which removed a predicted N-linked glycosylation site. ConclusionMost of the MeV isolates are sub-genotype H1a analyzed based on H gene， which are identical to those of the N gene. The predicted amino acid sequences of the H protein are relatively conserved at most of the functionally significant amino acid positions.