1.Double inhibitors diffuse synergy test for two kinds of extended-spectrum ?-lactamases
Lehai ZHANG ; Yunshuang FU ; Lixia MA
Chinese Journal of Laboratory Medicine 2001;0(04):-
Objectives To consider the reliability of using flucloxacillin (FCC) and clavulanic with extended spectrum cephalosporin synergy method (double inhibitors diffuse synergy test, DIDST) to detect AmpC ? lactamases (AmpC BLA) and extended spectrum ? lactamases (ESBLs). Method The FCC and clavulanic were regarded as the inhibitors of AmpC BLA and ESBLs respectively. The disks of ceftriaxone and cefepime were placed 20 mm away from the inhibitors, the disks of cefotaxime and the inhibitors were 25 mm apart. DIDST with a double disk synergy test, a cefoxitin three dimensional test, and a double disk enhancement test detected AmpC BLA and ESBLs in 56 strains of gram negative bacilli at the same time. Results 20 (35.71%) strains of ESBLs, 12 (21 43%) for AmpC BLA and 1 (1.78%) for ESBLs+AmpC BLA were found using DIDST, in 56 strains of G - B. During the double disk synergy test was used for ESBLs, 15 strains were found when the distance of the disks was within 25 mm, another 5 strains were found when the distance decreased to 20 mm. Twenty strains of ESBLs were found using the double disk enhancement test, and 12 strains of AmpC using the cefoxitin three dimensional test. The result of DIDST was similar to that of other three kinds of test. Conclusions DIDST is an accurate and reliable method using one plate to detect ESBLs and AmpC BLA of the same time. It is suitable for different levels of hospitals.
2.Study on bacteria contamination during the collection, processing and storage of umbilical cord blood
Leling ZHANG ; Lixia MA ; Sulan WANG ; Xindang WANG ; Fu LI ; Lehai ZHANG ; Xingli LIU ; Baijun SHEN
International Journal of Pediatrics 2012;39(2):212-214
ObjectiveTo evaluate bacteria contamination during collection,processing and storage of cord blood to gain insight into contamination mechanism and direct prevention.MethodsFresh cord blood was separated by hydroxyethyl starch (HES) to harvest nucleated cells.The bacteria contamination was tested by culturing 10 ml plasma-red cells with BacT/ALERT 3D-480 automatic blood culture system.Total 87 positive samples were further identified for bacteria species.Ninety six cord blood nucleated cells concentrate with bacteria positive stored in liquid nitrogen(LN2) for 6-7 years were thawed at 37 C and re-cultured for bacteria analysis.ResultsWe collected 19 062 umbilical cord blood.Among them,336 was bacteria positive ( contamination rate 1.8 % ).Eighty-seven positive samples were further investigated with facultative bacteria 58 (66.7 % ),aerobic 38(43.7% ) and anaerobic 17( 19.5% ),Gram- negative accounted for 68% while positive 32%.The most frequent bacteria were Escherichia coli ( 25.3% ),Streptacoccus intermediate ( 14.9% ) and Chromobacteria violaceum(9.2% ).Ninety-six nucleated cells concentrate with bacteria positive were cryopreserved at liquid nitrogen for researching.Of them,83 samples( 86% ) showed positive of bacteria culture after deep-low temperature storage for 6-7 years.ConclusionsBacteria contamination rate of the cord blood collection,processing and storage in 2000 ~ 2007 was 1.8%.Stored in liquid nitrogen for 6-7 years,the viability of bacteria was 86%.The aseptic procedures of cord blood collection in delivery room should be intensified.The bacteria re-culture following thawing of cord blood cells is necessary before clinical transfusion.
3.Inhibitor-based methods for detection of derepressed hyperproduction and plasmid-mediated AmpC β-lactamases
Lehai ZHANG ; Lixia MA ; Shifu WANG ; Changying YI ; Xingli LIU ; Sulan WANG
Chinese Journal of Laboratory Medicine 2008;31(6):648-652
Objective To investigate the reliability of using inhibitors including Phenylboronic acid (PBA)and Fqucloxacillin(FCC)in detecting derepressed hyperproduction and plasmid-mediated AmpC B-lactamases.Methods PBA and FCC were chosen as inhibitors and double-disk potentiation method and double-disk synergy method were used to detect positive and negative control strains of AmpC β-lactamases and 107 clinical isolates for AmpC β-lactamases production.The positive control strains included E.cloacae (029M),plasmid-mediated ACT-1 type of E.coli DH5a2919,MOX-1 type of k pheumoniae,LAT-2 type of E.coil.The negative control strains included E.cloacae 029(wild-type),E.coli SHV-1,E.coli SHV-2, E.coil SHV-5,E.coli TEM-1,E.coli TEM-3,k peumoniae SHV-18 and E.coli ATCC25922.We compared the results above with the three dimensional test(3-DT)to observe the accuracy in detecting AmpC-BLA.Results 3-DT together with PBA and FCC based inhibition tests showed the 4 positive control strains and the 9 negative control strains were determined as expected.AmpC-BILA was detected in 107 clinical isolates ofEnterobacteriaceaes.The positive rate of3-DTmethod is24.3%.The positive rates ofPBA.FCC double-disk potentiation method and double-disk synergy method are 30.8%(33/107),26.2%(28/107) and 23.4%(25/107),respectively.The conjugate results in two strains of P mirabilis and one strain of K.peumoniae were positive.They were all plasmid-mediated AmpC-Bi.A.There Was a higher false positive when using PBA and FCC-based double-disk potentiation method to detect the induction type of AmpC-BLA, but the accuracy of double-disk synergy method was high.Compared with the 3-DT,the coincidence rate using PBA and FCC-based double-disk synergy method is 99.1%.Conclusions Using PBA and FCC as inhibitors in the double-disk synergy test is a accurate and reliable method to detect AmpC-BLA regardless of derepressed hyperproduction type or plasmid-mediated type.
4.Expert consensus on standardized TORCH laboratory detection and clinical application
Yuning ZHU ; Shiqiang SHANG ; Yinghu CHEN ; Dapeng CHEN ; Liting JIA ; Wei QU ; Jiangwei KE ; Haibo LI ; Xiaoqin LI ; Xiuyun LIANG ; Yanqiu LIU ; Lijuan MA ; Liya MO ; Qiang RUAN ; Guosong SHEN ; Yuxin WANG ; Hong XU ; Jin XU ; Liangpu XU ; Xiaohong XU ; Enwu YUAN ; Lehai ZHANG ; Wenli ZHANG ; Xinwen ZHANG
Chinese Journal of Laboratory Medicine 2020;43(5):553-561
TORCH, which is considered as a series of pathogens, including the Toxoplasma gondii, Rubella virus, Cytomegalovirus or Herpes simplex virus, often infects the pregnant women to induce the the fetus or newborn infection by transplacental infection or exposure to contaminated genital tract secretions at delivery. Increasing evidence have been confirmed that the infection of TORCH may cause the miscarriage, premature birth, malformed fetus, stillbirth, intrauterine growth retardation, neonatal multiple organ dysfunction and other adverse pregnancy outcomes. For most TORCH-infections cases may lacking the effective treatments during pregnancy, and it is important to achieve the effacing monitoring of TORCH infections before and during pregnancy. The laboratory testing of TORCH has the great significance. However, the consensus opinions still need to improve the the standardization of TORCH testing process and the correct interpretation. Based on the characteristics of the TORCH detection method, this article gives a consensus opinion on the standardized detection and clinical application of TORCH from the laboratory perspective according to the characteristics and types of infection of different pathogens.
5.Correlation of Gut Microbiome Between ASD Children and Mothers and Potential Biomarkers for Risk Assessment.
Ning LI ; Junjie YANG ; Jiaming ZHANG ; Cheng LIANG ; Ying WANG ; Bin CHEN ; Changying ZHAO ; Jingwen WANG ; Guangye ZHANG ; Dongmei ZHAO ; Yi LIU ; Lehai ZHANG ; Jun YANG ; Guimei LI ; Zhongtao GAI ; Lei ZHANG ; Guoping ZHAO
Genomics, Proteomics & Bioinformatics 2019;17(1):26-38
Variation of maternal gut microbiota may increase the risk of autism spectrum disorders (ASDs) in offspring. Animal studies have indicated that maternal gut microbiota is related to neurodevelopmental abnormalities in mouse offspring, while it is unclear whether there is a correlation between gut microbiota of ASD children and their mothers. We examined the relationships between gut microbiome profiles of ASD children and those of their mothers, and evaluated the clinical discriminatory power of discovered bacterial biomarkers. Gut microbiome was profiled and evaluated by 16S ribosomal RNA gene sequencing in stool samples of 59 mother-child pairs of ASD children and 30 matched mother-child pairs of healthy children. Significant differences were observed in the gut microbiome composition between ASD and healthy children in our Chinese cohort. Several unique bacterial biomarkers, such as Alcaligenaceae and Acinetobacter, were identified. Mothers of ASD children had more Proteobacteria, Alphaproteobacteria, Moraxellaceae, and Acinetobacter than mothers of healthy children. There was a clear correlation between gut microbiome profiles of children and their mothers; however, children with ASD still had unique bacterial biomarkers, such as Alcaligenaceae, Enterobacteriaceae, and Clostridium. Candidate biomarkers discovered in this study had remarkable discriminatory power. The identified patterns of mother-child gut microbiome profiles may be important for assessing risks during the early stage and planning of personalized treatment and prevention of ASD via microbiota modulation.
Adult
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Animals
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Autism Spectrum Disorder
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microbiology
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Bacteria
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classification
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genetics
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isolation & purification
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Biomarkers
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Child
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Child, Preschool
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Cohort Studies
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Female
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Gastrointestinal Microbiome
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Humans
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Male
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Mice
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Mothers
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Risk Assessment