Rapid culture and identification of human parainfluenza viruses / 医学研究生学报

Objective Parainfluenza virus is an important pathogen of lower respiratory tract infections in infants and young children.This study was to search for a method for rapid culture and identification of human parainfluenza viruses from nasal swabs. Methods Nasal swab specimens were collected from 0-5 years old children with acute respiratory tract infection.The specimens were inoculated onto 96 plates with prefabricated LLC-MK2 cells and then centrifuged for 1 hour at 3000 r/min and also inoculated using the traditional culture method, followed by addition of virus mainte-nance medium containing 4 μg/mL TPCK trypsin.The cytopathic effect was observed daily, and hemagglutination and blood absorption tests were done at 2, 5, and 8 days after inoculation.In case of posi-tive result of either test, the specimen was subjected to immunofluo-rescence staining. Results Six strains of parainfluenza virus were isolated from the 83 nasal swab specimens, with a positive rate of 7.2%.There was a significant difference in the rate of separation be-tween the rapid and traditional culture methods after 2 days of culturing (7.2%vs 0%, P<0.05).The infected cells produced a cy-topathic effect that characterized by syncytium and crush formation.Hemagglutination and blood adsorption tests were positive at 4℃and negative at the room temperature.Immunofluorescence staining exhibited specific apple green fluorescence. Conclusion The method for rapid culture and identification of human parainfluenza viruses in nasal swab specimens was successfully established, which can be used to obtain and identify parainfluenza viruses with virulence and biological activity in 2 days.

Regulation of bone marrow mesenchymal stem cells on lymphocyte proliferation of type Ⅰdiabetic rats / 中国免疫学杂志

Objective:To investigate the regulation mechanisms of the bone marrow mesenchymal stem cells on lymphocyte pro -liferation of type I diabetic rats .Methods:The rat bone marrow mesenchymal stem cells were isolated , cultured and identified and the effect on lymphocyte proliferation of type Ⅰdiabetic rat was observed by MTT assay , and analyze the CD 4 +CD25 +regulatory T cell ra-tio, cell cycle and apoptosis of type I diabetes rat by flow cytometric .Results:B and C groups was significantly lower than the absor-bance values of group A,the differences between the data were statistically significant (P<0.05), C group was significantly lower than group B absorbance values, the difference was significant (P<0.05);the CD4 +CD25 +regulatory T cells of B and C groups were sig-nificantly higher than group A, the differences of the data were statistically significant (P<0.05), the CD4 +CD25 +regulatory T cell ratio of C group significantly higher than that group B , the differences were statistically significant (P<0.05);the apoptosis levels of B and C groups were significantly higher than group A , the differences were statistically significant (P<0.05), the apoptosis levels of C group were significantly higher in group B , the differences were statistically significant (P<0.05).Conclusion:Bone marrow mesen-chymal stem cells can significantly inhibit lymphocyte proliferation of type Ⅰdiabetic rats, and it may regulate CD4 +CD25 +regulatory T cells, promote apoptosis, thereby affecting the immune function of T lymphocytes , and play its rejection.

The distribution of high pathogenicity island in multiple-drug-resiatance gram-negative bacilli and analyzation of DNA sequence / 中国医师杂志

Objective To investigate the distribution of high pathogenicity island(HPI)in multiple-drug-resistance gram-negative bacilli and analyze the protein sequence.Methods To amplify thefyuA-irp2 gene cluster of the 84 isolates by multiple polymerase chain reaction(PCR),the product was subsequently sequenced.Results The positive rate ofirpl,irp2,irp3,irp4 and fyuA was 40.48％,41,67％,5.95％,O％and 16.67％,respectively.Theamino sequence offyuA comefromEC06748,Kp7151 and PAE7 was usedto compare with AL590842,there are 100％identities.Amino sequence ofirp2 come from Kp49 and Kp51 have 99％identities with AAA27636.1,but amino sequence of irp2 come from EC04 and EC07 only have 90％identities with 1176840.The GenBank accession number is FJ211852 and FJ211851.Amino sequence ofirpl come fromKp 10,Kp49 and Kp51 have 99％identities with AL590842。and amino sequence ofirp3 come from EC03,Kp51,Kp10 and Kp49 have 97％identities with CAA73128.There are the same mutation among the same species,and different mutation among different species.Conclusion There was different extant mutant lost in thefy～t-i,v2 gene cluster in multiple-drug-resistanee gram-negative bacilli.