1.Molecular Characterization of Segments S7 to S10 of a Southern Rice Black-streaked Dwarf Virus Isolate from Maize in Northern China
Xiao YIN ; Feifei XU ; Fangqiang ZHENG ; Xiangdong LI ; Baoshen LIU ; Chunqing ZHANG
Virologica Sinica 2011;26(1):47-53
Southern rice black-streaked dwarf virus(SRBSDV)is a novel Fijivirus prevalent in rice in southern and central China, and northern Vietnam. Its genome has 10 segments of double-stranded RNA named S1 to S10according to their size. An isolate of SRBSDV, JNi4, was obtained from naturally infected maize plants from Ji'ning, Shandong province, in the 2008 maize season. Segments S7 to S10 of JNi4 share nucleotide identities of 72.6%-73.1%, 72.3%-73%, 73.9%-74.5% and 77.3%-79%, respectively, with corresponding segments of Rice black-streaked dwarf virus isolates, and identities of 99.7%, 99. 1%-99.7%, 98.9%-99.5%, and 98.6%-99.2% with those of SRBSDV isolates HN and GD. JNi4 forms a separate branch with GD and HN in the phylogenetic trees constructed with genomic sequences of S7 to S10. These results confirm the proposed taxonomic status of SRBSDV as a distinct species of the genus Fijivirus and indicate that JNi4 is an isolate of SRBSDV. Shandong is so far the northernmost region where SRBSDV is found in China.
2.Treatment of traumatic proximal interphalangeal joint defect with artificial joint replacement
Ao GUO ; Liangjun ZHENG ; Jun LI ; Yanquan JIN ; Lingming CAI ; Fangqiang PAN
Chinese Journal of Microsurgery 2012;35(1):20-22
ObjectiveTo investigate the treatment efficacy of traumatic proximal interphalangeal (PIP)joint defects with prosthetic replacement.MethodsFrom September 2007 to November 2010, ten patients with joint defect injuries were treated by joint prosthetic replacement (5 index fingers,4 middle fingers,and 1 ring finger),including a reconstructed middle finger.Joint motion range and postoperative pain of all cases were measured to evaluate the treatment.ResultsAll cases went through a smooth operation with primary wound healing,and with neither intraoperative nor postoperative complications happened.The follow-up period was range from 8 months to 2 years.The active motion arcs of PIP joints ranged from 50° to 80°,and satisfactory appearances as well. According to assessment standard of upper extremity described by Chinese Hand Surgery Association,the treatment outcome were excellent in 6 fingers,good in 3 fingers,general in 1 finger.ConclusionJoint prosthetic replacement is a new effective method to treat traumatic proximal interphalangeal joint defect,which is a simple operation with advantages of little trauma and rapid recovery.
3.Distribution and antimicrobial resistance of coagulase-negative staphylococci isolated from cerebrospinal fluids in neurosurgical patients
Guanghui ZHENG ; Chu ZHENG ; Yan ZHANG ; Mingzhong TANG ; Fangqiang LI ; Xiaozheng DING ; Yanxia LIANG ; Xixiong KANG ; Guojun ZHANG
Chinese Journal of Clinical Infectious Diseases 2016;9(4):355-358
Objective To investigate the distribution and antimicrobial resistance of Coagulase-negative staphylococci ( CoNS) isolated from cerebrospinal fluids in neurosurgical patients.Methods CoNS strains isolated from cerebrospinal fluids of neurosurgical patients were collected from Beijing Tiantan Hospital of Capital Medical University during January 2013 and December 2015.CoNS infection was diagnosed according to the standards of US Centers for Disease Control and Prevention, and the distribution and antimicrobial resistance of pathogenic CoNS strains were analyzed. Results A total of 19 756 cerebrospinal fluid specimens were collected and 1 386 bacterial strains were isolated, in which 650 (46.9%) were CoNS.Among 650 CoNS strains, 130 were diagnosed as the pathogen, and the top 4 CoNS species were Staphylococcus epidermidis (77/130, 59.2%), Staphylococcus hominis (18/130, 13.8%), Staphylococcus haemolyticus (11/130, 8.5%) and Staphylococcus capitis (9/130, 6.9%).The rest 520 CoNS strains were contaminating strains.According to antimicrobial susceptibility test, there were 103 strains of methicillin-resistant CoNS (MR-CoNS) accounting for 79.1% (103/130).And among 77 Staphylococcus epidermidis isolates, 67 were MR-CoNS strains (87.0%) .More than 90.0%Staphylococcus epidermidis isolates were sensitive to vancomycin and linezolid, and the rest CoNS strains were also highly sensitive to these two antibacterial agents.Conclusions CoNS plays an important role in post-surgery infection in neurosurgical patients, and Staphylococcus epidermidis is the dominant CoNS species.Most CoNS strains are methicillin-resistant, but are highly sensitive to vancomycin and linezolid.
4.Diagnostic value of procalcitonin and lactate in cerebrospinal fluid combined with conventional biomarkers for post-neurosurgical bacterial meningitis
Guanghui ZHENG ; Yan ZHANG ; Fangqiang LI ; Mingzhong TANG ; Hong LYU ; Guojun ZHANG
Chinese Journal of Clinical Infectious Diseases 2019;12(2):101-106
Objective To investigate the diagnostic value of procalcitonin ( PCT) and lactate in cerebrospinal fluid (CSF) combined with conventional biomarkers for post-neurosurgical bacterial meningitis (PBM).Methods Clinical data of 213 patients with post-neurosurgical meningitis admitted in Beijing Tiantan Hospital, Capital Medical University from March 2017 to December 2017 were retrospectively analyzed, including 85 cases of PBM and 128 cases of post-neurosurgical aseptic meningitis ( PAM).The diagnostic value of CSF procalcitonin , lactate and other 12 conventional biomarkers for PBM was analyzed by multivariate logistic regression.A prediction algorithm was generated and its diagnostic value for PBM was assessed with receiver operating characteristic curve (ROC).Results The univariate analysis showed that CSF cell count, CSF leukocyte count , CSF protein concentration , CSF glucose concentration, CSF glucose/blood glucose ratio, CSF PCT and CSF lactate were significantly associated with PBM.Multivariate logistic regression analysis showed that CSF PCT , CSF lactate, CSF protein concentration and CSF glucose /blood glucose ratio were independent predictive factors for PBM.The predictive algorithm score =4.315 ×CSF PCT+0.822×CSF Lactate+0.009×CSF protein concentration -5.480×CSF glucose/blood glucose ratio-3.074.The predictive algorithm has the largest area under the ROC curve ( AUC =0.947), and the sensitivity and specificity of the predictive algorithm score were 90.60% and 85.10%, respectively.The positive predictive value , negative predictive value and the accurate rate of the algorithm in diagnosis of PBM were 84.06%, 94.44% and 90.40%, respectively.Conclusion The predictive algorithm based on the combination of CSF PCT and CSF lactate with CSF protein concentration and CSF glucose /blood glucose ratio has a good diagnostic value for PBM.It can shorten the diagnosis time of PBM and improve the clinical outcomes.
5.Clinical significance and cut-off value of the infection of coagulase-negative staphylococcus obtained from cerebrospinal fluid specimens in neurosurgical patients
Cuanghui ZHENG ; Guojun ZHANG ; Fangqiang LI ; Yan ZHANG ; Mingzhong TANG ; Xixiong KANG
Chinese Journal of Laboratory Medicine 2017;40(9):707-710
Objective To study on the contribution and cut-off value of coagulase negative staphylococcus (CoNS) in laboratory tests of postoperative infection in neurosurgery and optimize the diagnostic criteria of infection.Methods It made a retrospective study of 650 cerebrospinal fluid (CSF)specimens from neurosurgical patients,who were infected CoNS in Beijing Tiantan Hospital affiliated to Capital Medical University during 2013-2015.The epidemiological data were collected and 8 routine clinical laboratory tests were performed.T test was used to compare the difference among the groups.By making receiver operating characteristic (ROC) curve,the area under the curve (AUC),cut-off value,sensitivity and specificity were obtained.Results A total of 19 756 CSF specimens were collected and 650 CoNS were isolated.The separation rate of CoNS was 3.3% which was the most frequently isolated bacteria.The differences of cerebrospinal fluid white blood cell count (3 598.6 ± 1 884.3,678.1 ± 629.1,t =2.662,P =0.012),multinucleated cell ratio in cerebrospinal fluid(76.0 ±32.6,46.8 ±29.9,t =9.593,P =0.001),cerebrospinal fluid glucose concentration (5.9 ± 2.12,6.2 ± 1.92,t =-16.296,P =0.001) and cerebrospinal fluid glucose concentration/blood glucose concentration (0.3 ± 0.16,0.63 ± 0.31,t =-11.968,P =0.000) among groups were statistically significant.The AUCs of cerebrospinal fluid white blood cell count,cerebrospinal fluid glucose and cerebrospinal fluid glucose/blood glucose were more than 0.8,and the sensitivities of the three indicators were more than 80.0%.In addition,the specificity of cerebrospinal fluid glucose concentration/blood glucose concentration was more than 0.9.Conclusions CoNS was the main pathogenic bacteria of neurosurgical infections in a hospital.Cerebrospinal fluid white blood cell count,cerebrospinal fluid glucose and the ratio of cerebrospinal fluid glucose and blood glucose could be used for auxiliary diagnosis of CoNS infections in neurosurgical patients.
6.Analysis of drug resistance of pathogenic bacteria from different origins in neurosurgery ward
Guanghui ZHENG ; Fangqiang LI ; Yan ZHANG ; Mingzhong TANG ; Xixiong KANG ; Guojun ZHANG
International Journal of Laboratory Medicine 2018;39(13):1610-1614
Objective To explore the differences in antibiotic resistance among pathogenic bacteria isolated from respiratory tract and cerebrospinal fluid specimens in neurosurgery wards .Methods Antibiotic resist-ance tests were performed to analyze the antibiotic sensitivities of pathogenic bacteria isolated from respiratory tract and cerebrospinal fluid specimens in the neurosurgery wards at Beijing tiantan hospital affiliated to cap-ital medical university ,from January 2012 to December 2016 .Statistical analysis was performed using the t test or M-W test to determine the differences between the two independent samples were statistically significant . Results From January 2012 to December 2016 ,6 091 strains isolated from respiratory tract and 1 597 strains isolated from CSF specimens were obtained from patients in the neurosurgery wards of a hospital .Based on the results of the t test ,differences in the antibiotic sensitivities of pathogenic bacteria isolated from these two specimens were statistically significant .Three Gram-negative bacteria ,Pseudomonas aeruginosa ,Klebsiella pneumoniae and Acinetobacter baumannii ,showed statistically significant differences in antibiotic sensitivities between respiratory tract and cerebrospinal fluid specimens (P<0 .05) ,but this difference was not statistically significant in Staphylococcus aureus (P>0 .05) .Pathogenic bacteria isolated from two specimens showed sta-tistically significant differences in sensitivity to β-lactam antibiotics ,polymyxin B ,vancomycin and linezolid (P<0 .05) .Conclusion The sensitivity differences between bacteria isolated from respiratory tract and cere-brospinal fluid specimens are statistically significant .Several reasons ,such as antibiotic-induced antibiotic re-sistance ,horizontal gene transfer are responsible for this result .
7.Application of a microfluidic chip platform in rapid diagnosis of post-neurosurgical bacterial infection
Guanghui ZHENG ; Ruimin MA ; Fangqiang LI ; Yan ZHANG ; Mingzhong TANG ; Yan ZHANG ; Hong LYU ; Guojun ZHANG
Chinese Journal of Clinical Laboratory Science 2019;37(4):246-250
Objective:
To establish and evaluate a microfluidic chip platform for the rapid diagnosis of post-neurosurgical bacterial infection.
Methods:
The pathogens isolated from patients with post-neurosurgical bacterial infection in Beijing Tiantan Hospital Affiliated to Capital Medical University during 2007 and 2016 and the epidemiological data from China drug resistance monitoring network CHINET were analyzed retrospectively. Based on the retrospective data and the molecular epidemiological information of drug-resistant bacteria reported in the literature, target pathogens and drug resistance gene parameters were selected. The microbial identification parameters from 10 different bacteria, including Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus epidermidis, Enterobacter cloacae, Staphylococcus aureus, Escherichia coli, Enterococcus faecium, Enterococcus faecalis, Stenotrophomonas maltophilia and Pseudomonas aeruginosa, and the parameters of 15 drug resistance genes, including mecA, vanA, vanB, aacC1, aadA1, bla CTX-M-1 , bla CTX-M-9 , bla GES-1 , bla OXA-23 , bla OXA-24 , bla OXA-58 , bla OXA-66 , bla KPC-2 , bla IMP-4 and bla VIM-2 , were selected for designing a microfluidic chip platform. Using MAIDI-TOF MS for bacterial identification, multiplex PCR for the detection of drug resistance genes, micro-broth dilution method for the detection of drug resistance phenotypes and ESBLs screening test as reference methods, 13 known bacteria were used to evaluate the preliminary performance of the established microfluidic chip platform, and 108 cerebrospinal fluid bacterial culture positive specimens were used to evaluate the clinical application value of the microfluidic chip platform.
Results:
The identification rates of 13 known strains and the coincidence rate of drug resistance genes were 100%. The coincidence rate of identification results for 108 cerebrospinal fluid bacterial culture positive specimens between the microfluidic chip platform and the MALDI-TOF MS method was as high as 94.44%. The coincidence rates of drug resistance phenotype of carbapenems, oxacillin, vancomycin, ESBLs and genotype between the microfluidic chip platform and the micro-broth dilution method or ESBLs screening test were above 90%.
Conclusion
The established microfluidic chip platform is fast and accurate, and has application value in microbial identification and the prediction of drug resistance, which may be used as an important supplementary method in the diagnosis of post-neurosurgical bacterial infection.