2.Research of stenotrophomonas maltophilia integrons distribution in Yantai area and their variable regions carrying drug resistance gene cassettes
Jiangdong DU ; Peiwen LIAN ; Yingfeng LIANG ; Qianqing TANG
International Journal of Laboratory Medicine 2014;(13):1667-1669
Objective To analyze the resistance of Stenotrophomonas maltophilia to commonly used antibacterial drugs,and to investigate the existence status of 3 kinds of integron(Ⅰ,Ⅱand Ⅲ)and the carrying drug resistance gene cassettes so as to offer help for better preventing and controlling the infectious diseases caused by stenotrophomonas maltophilia in local place.Methods 51 strains of Stenotrophomonas maltophilia from clinical samples were collected and the minimum inhibitory concentration(MIC)of 17 kinds of antibacterial drugs to stenotrophomonas maltophilia was measured by the broth microdilution antifungal susceptibility test(Mi-AFST).3 kinds of integron(Ⅰ,Ⅱand Ⅲ)were amplified by PCR with primers designed according to registrated DNA se-quence in GenBank.The variable region products in the positive integron strains were amplified and performed the sequencing analy-sis.The homological comparison in the Genebank database was performed on the sequencing results for finding out what gene was included in variable domain of those integrons.Results (1)Among 51 strains of stenotrophomonas maltophilia,41 srains (80.39%) were collected from sputum samples,and the infected crowd was dominated by individuals aged over 60 years,38 strains accounted for 74.5%.In the department distribution,20 strains(39.22%)were collected from ICU,13 strains (25.49%)from the respiratory department and 6 strains(11 .76%)from the veteran cardres wards,which accounted for the larger proportion.(2)The drug suscep-tibility test demonstrated that stenotrophomonas maltophilia strains had the higher resistance to most of commonly used antibacteri-al drugs,some strains even showed the multi-drug resistance to over 9 kinds of antibacterial drugs.(3)The PCR gene amplification results showed that 7 strains (13.7%)were positive integronⅠ,while no strains containing integron Ⅱ or ⅢI were detected;the resistance genes carried in the variable region of integron I included the 5 kinds of aacA4,aadA1,catB8,dfrA17 and aphA15.Conclu-sion Stenotrophomonas maltophilias has relatively high resistance to majority of commonly used antibacterial drugs in clinic,and some strains show the muti-drug resitance.IntegronⅠis one of important factors for the multi-drug resistance of Stenotrophomonas maltophilias.
3.Viral metagenomic analysis of fecal samples from diarrhea children with positive picobirnaviruses
Feng-Zhen YANG ; Maoli YI ; Jinying WU ; Yingfeng LIANG ; Qinbo ZANG ; Lihua JIANG ; Zhimei ZHOU ; Guangming SUN
Chinese Journal of Applied Clinical Pediatrics 2018;33(19):1495-1498
Objective To investigate positive picobirnaviruses(PVBs)infection and its association with unex-plained diarrhea in children. Methods From January to December 2015,the Clinical Microbiology Testing Center of Xuzhou Central Hospital as the sampling location,7 PVB reverse transcription - polymerase chain reaction(RT - PCR)- positive fecal samples with diarrhea were collected from children under 6 years old and 4 samples from healthy chil-dren were obtained and all the samples were analyzed by viral metagenomics to investigate the relationship between PVBs and diarrhea in children. Phylogenetic analysis of RdRp in the isolated PVB sequences was carried out to clarify the relationship between PVB classification and diarrhea. Results All the 7 diarrhea feces contained high titers of PVB sequences,while 3 of the controls were negative,and 1 with low titers of PVB. RdRp analysis was carried out on the iso-lated PVB sequences,which displayed that 7 RdRp sequences caming from 7 fecal samples separately,so named ChXz- 1 to ChXz - 7 respectively. Phylogenetic analysis based on the predicted amino acid sequences of RdRp from this study and whole RdRp sequences available in the GenBank database indicated that the 7 RdRp sequences belonged to 3 genogroups,in which ChXz - 1,ChXz - 2,ChXz - 3 belonging to genogroup Ⅰ,ChXz - 4,ChXz - 5,ChXz - 7 belong-ing to genogroup Ⅱ,and ChXz - 6 belonging to genogroup Ⅲ. Conclusions PVBs might be the cause of diarrhea in children in this study,and all the 3 different PVBs may lead to diarrhea.
4.Simulation Analysis of Firefighter Training Postures with Loads
Na CHEN ; Man LIANG ; Yitong HU ; Yingfeng YUAN
Journal of Medical Biomechanics 2024;39(1):145-150
Objective To study the injury risk and fatigue status of firefighters with different training postures under load-bearing conditions to reduce the occurrence of physical injuries and occupational diseases.Methods First,a questionnaire was administered to investigate the training injury conditions of firefighters in a fire-rescue brigade.Considering the exercise fatigue factor,which accounts for the highest proportion of injury causes,lower back analysis,static strength analysis,fatigue analysis,comfort analysis,and other human factor analysis tools in Jack software were used to analyze four common firefighter water-shooting training postures.Training postures while climbing a five-storey building with loads and a hooked ladder were also simulated.Results Injury caused by exercise fatigue accounted for 69.8%of injuries and was the most important injury-causing factor.The risk of knee and ankle joint injuries increased in all four water-shooting postures.The comfort levels of the four water-shooting postures from high to low were shoulder,standing,kneeling,and lying postures.For the entire dynamic training process,while climbing the five-storey building with loads and climbing the hooked ladder,firefighters did not have an increased risk of lower back injury but had an increased risk of ankle and knee joint injuries.Conclusions Some training postures are uncomfortable for firefighters,and they experience body discomfort during firefighting training with loads,thereby increasing injury risk.These results provide scientific references for the prevention and reduction of firefighter training injuries,and the formulation of reasonable training plans and targeted protective measures.
5.Nucleotide sequence analysis for a new HLA-B allele HLA-B*13:01:06*.
Baiyu XIONG ; Yin TAN ; Yingfeng HUANG ; Shaoyu YANG ; Hongtu LUO ; Liang SHEN ; Taichen ZHOU ; Cangjun XIAO
Chinese Journal of Medical Genetics 2014;31(6):790-792
OBJECTIVETo confirm a new allele HLA-B*13:01:06 and analyze its nucleotide sequence.
METHODSGenomic DNA was extracted using a Qiagen DNA extraction kit. Nucleotide sequences of HLA-A, HLA-B, HLA-C and HLA-DRB1 were analyzed by polymerase chain reaction-sequence based typing (PCR-SBT). HLA high-resolution results were assigned, and the nucleotide sequences of HLA-B locus was compared with that of HLA-B*13:01:01.
RESULTSThe nucleotide sequence of the new allele shows a strong similarity to that of HLA-B*13:01:01. One nucleotide in exon 2 has changed from G to A at position 219 (codon 49 GCG>GCA), which however did not result in amino acid change.
CONCLUSIONThe novel allele verified by sequencing has been submitted to GenBank and officially named as HLA-B*13:01:06 by the World Health Organization HLA Nomenclature Committee.
Alleles ; Amino Acid Sequence ; Base Sequence ; Exons ; HLA-B Antigens ; genetics ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Sequence Analysis, DNA