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【Objective】 To evaluate the application value of nucleic acid testing (NAT) by studying the NAT-yield of syphilis screening reactive blood from five blood centers. 【Methods】 The blood samples and demographic information of syphilis screening positive donors were collected from five domestic blood centers, i. e. Chongqing, Guangxi, Luoyang, Liuzhou, Mianyang and Urumqi. The treponema pallidum particle agglutination (TPPA) and the established SYBR Green qPCR method were used to analyze the difference between the results of NAT and the other two test results. 【Results】 Among 1 679 reactive blood samples for syphilis screening, 819 were confirmed positive by TPPA, accounting for 49%, with the false positive rate exceeded 50%. As to NAT results, the NAT-yield of syphilis screening reactive samples and confirmed positive samples was the same (both 2.20%); the NAT-yield of TPPA-positive and TPPA-negative samples were 2.20% and 2.74%, respectively. 【Conclusion】 Primary syphilis screening by ELISA has high sensitivity, but also presents high false positive rate. Although TPPA confirmatory test has strong specificity, it cannot reflect the existence of T. pallidum. Therefore, NAT may be used as a supplementary test for syphilis screening so as to more effectively ensure the safety of blood transfusion and blood supply.
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【Objective】 To explore the influence of common methods of reducing non-viral nucleic acid on the abundance of plasma virus group. 【Methods】 Three kinds of library construction, five kinds of centrifugation conditions, two kinds of filters, four kinds of enzymes and four concentrations of chloroform were used to treat plasma samples added quantitatively 2.16 mL of pseudorabies virus(PRV) and 2.16 mL of porcine parvovirus(PPV). A total of 21.6 mL of plasma samples were processed, including 54 samples. Subsequently, nucleic acid was extracted, mitochondrial DNA(mtDNA) and two viruses were quantitated, the library of the next generation sequencing was constructed, Illumina NovaSeq 6000 was used for the next generation sequencing. The sequencing data were compared with Kraken Py 2.0 software, and the species annotation analysis was conducted. The corresponding species classification information of each segment was obtained to analyze the impact of different reducing non-viral nucleic acid methods on the relative abundance of microorganisms and two indicator viruses. 【Results】 After sequencing by Illumina NovaSeq 6000, 306.27 GB raw data and 193.17 GB clean data were obtained, with Q20>90%, Q30>85%, Error Rate of 0.03%, and average GC Content of 45.02%. The DNA library construction process significantly increased the proportion of microbial sequences and the PRV abundance [(91.8±0.5)%](P<0.05); RNA library construction and combined library construction can increase the abundance of Pestivirus, an RNA virus, and the PRV abundance was(17.7±3.3)% and(8.1±1.5)% respectively. The Ct value of mtDNA was increased and the proportion of human sequence decreased to less than(89.5±1)%, while the proportion of microbial sequence increased to (2.4±0.03)% after treatment of five centrifugation conditions(P<0.05); After centrifugation at 4℃, 100 g, 30 min, the PRV abundance was increased to (40.6±6)%, and centrifugation at 4℃, 4 000 g, 45 min reduced the PRV abundance to (4.1±0.01)%(P<0.05). Both of 0.22-μm filter and 0.45-μm filter increased the Ct value of mtDNA to above 25.56±0.13, decreased the proportion of human sequence to less than (86.1±0.6)%, increased the proportion of microbial sequence to (3.1±0.1)% and (3.4±0.2)%, and decreased the PRV abundance to (1.6±0.3)% and (4.1±0.7)%(P<0.05), while there was no statistical difference in the effect on PPV concentration and abundance. DNase Ⅰ and Benzonase increased the Ct value of PPV to 25.65±0.06 and 25.36±0.45, decreased the proportion of human sequence to (81.7±5.6)% and (72.8±6.7)%, and increased the proportion of microbial sequence and PRV abundance to (11.0±4.1)% and (16.1±4.7)%, (55.8±2.3)% and (39.0±8.9)%, respectively(P<0 05); After treatment with RNase A, the Ct value of PRV increased to 25.20±0.11, and the human sequence proportion decreased to (85.4±5.6)%(P<0 05); Lysozyme had no effect on removing non-viral nucleic acid. The chloroform of 1%, 5%, 10% and 20% increased Ct value of PRV and mtDNA to no less than 27.17±0.21 and 25.68±0.04; Only 10% chloroform increased the proportion of microbial sequences to (3.1±1.2)%(P<0.05); The abundance of PRV with 1% and 5% chloroform treatment was increased to (48.7±13.3)% and (42.1±5.5)%(P<0.05), while 10% and 20% chloroform reduced PRV abundance to (1.0±0.5)% and (3.4±2.8)%(P<0.05). There was no statistical difference in the effect of chloroform with four contents on PPV abundance. 【Conclusion】 Centrifugation at 4℃, 5 000 g, 10 min is suitable for increasing the overall abundance of virus, and centrifugation at 4℃, 100 g, 30 min is suitable for increasing the content of virus similar to PRV. 0.45-μm filter, DNase Ⅰ, Benzonase and low concentration chloroform can effectively reduce the proportion of non-viral nucleic acid sequence in plasma to increase the abundance of the indicated virus group. Thus, the enrichment effect of plasma meta-virome is closely related to the nature of the virus, and the appropriate virus enrichment method should be selected according to the research purpose to establish the corresponding enrichment strategy.
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【Objective】 To explore the composition of culturable bacteria in platelets through bacterial culturomics and verify the results of culturomics and metagenomics to improve the detection rate of bacteria in platelets. 【Methods】 Platelet samples from 6 healthy people were collected. Eight kinds of culture media were placed in aerobic conditions and 12 kinds of culture media were placed in anaerobic conditions for large-scale culture and isolation of bacteria in platelets. The isolated single colony was identified by 16S rRNA gene sequencing. The bacterial abundance of healthy human platelet microbiome was analyzed by metagenomic sequencing, and the cultivable bacterial species in platelets was confirmed based on metagenomic and culturomics results. 【Results】 A total of 90 strains of bacteria belonging to 3 phylums, 5 classes, 5 orders, 7 families, 9 genus and 23 species were isolated from 6 platelet samples by culturomics. Among them, the strains with more monoclonal clones at the species level were Brevundimonas aurantiaca (16.7%), Bacillus sp. Y1 (15.6%), Cutibacterium acnes (14.4%) and Brevibacillus brevis (13.3%). The platelet samples sequenced by mNGS showed that the abundance values of Proteobacteria, Firmicutes and Actinobacteria were high. The bacteria detected by both culturomics and metagenomic sequencing methods were as follows: Firmicutes: Bacillus sp. Y1, B. thuringiensis, B. cereus, B. mobilis, B. velezensis, Staphylococcus epidermidis, and Brevibacillus brevis; Actinobacteria: Cutibacterium acnes; Proteobacteria: Escherichia coli and Delftia tsuruhatensis. 【Conclusion】 The mutual validation of culturomics and metagenomics has identified some bacteria, proving that bacteria exist in platelets.
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【Objective】 To investigate the effectiveness of multilink real-time fluorescence quantitative PCR (qPCR) in the detection of common pathogens in transplantation. 【Methods】 The primers of the qPCR detection system were designed for 24 common infectious pathogens after clinical transplantation, and the standard plasmids of each pathogen were used to verify the qPCR reaction.After the primer probe effect and concentration of each pathogen reaction system in this experiment was optimized, the sensitivity, correlation coefficient (R2) and amplification efficiency (E) of qPCR method were analyzed and confirmed.Twenty-two samples from patients, who underwent liver and kidney transplantation in transplant ICU of Sichuan Provincial People′s Hospital, were used to verify the application of the detection system.The total nucleic acid of 100 μL was extracted from each individual and divided into two aliquots, which were detected by multi-link qPCR reaction system and analyzed by high-throughput sequencing method (NGS). At the same time, samples (2 mL each) were taken from the transplanted patients for microbial culture.The results of the three detection methods were compared, and the NGS method was taken as the gold standard to analyze the positive detection rate of the multi-link qPCR method and its difference with the culture method and NGS. 【Results】 The lower limit of qPCR detection for 24 pathogens in the established qPCR detection system was 101cp/μL(R2>0.99), with the positive rate of pathogens at 59.1% (13/22), showing significant difference versus microbial culture (18.2%, 4/22)(P<0.05), but not versus NGS (63.6%, 14/22)(P>0.05). Percentage of pathogens detected was as follows: human herpetic virus type 6 (HHV-6) 30.8% (4/13), cytomegalovirus (HCMV) 23.1% (3/13), Epstein-Barr virus (EBV) 23.1% (3/13), human parvovirus B19 15.4% (2/13), Haemophilus influenzae (Hin) 15.4% (2/13), Enterococcus faecium (EFM) 15.4% (2/13), Clostridium difficile 15.4% (2/13), Escherichia coli 7.7% (1/13), Stenotrophomonas maltophilia (Sma) 7.7% (1/13), Klebsiella pneumoniae (Kpn) 7.7% (1/13), Enterococcus faecalis (Efa) 7.7% (1/13) and Streptococcus pneumoniae (Spn) 7.7% (1/13). The consistency rate of pathogens detected by the three methods was 32% (7/22), among which the consistency rate of multi-link qPCR with NGS method was 59% (13/22), and multi-link qPCR with microbial culture was 41% (9/22). 【Conclusion】 Compared with the microbial culture, the multi-link qPCR method demonstrated high sensitivity, accurate quantification, short time and low cost for the detection of common pathogens in clinical transplantation.Multi-link qPCR combined with NGS and microbial culture is helpful to quickly predict the pathogen infection status of patients after transplantation.
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【Objective】 To investigate the distribution of Hepatitis B virus(HBV)genotypes and the genetic characteristics of genotype B HBV populations among voluntary blood donors in five regions of China. 【Methods】 A total number of 630 plasma samples from blood donors with positive HBV HBsAg neutralization test from 2014 to 2016 in Guangxi Blood Center, Chongqing Blood Center, Urumqi Blood Center, Mianyang Central Blood Station and Luoyang Central Blood Station were collected. The S-region sequence of the HBV genome was amplified by semi-nested PCR and followed with Sanger sequencing in order to investigate the HBV genotype distribution and population genetics. 【Results】 Among the voluntary blood donors in five regions, 55 cases of HBV S gene fragments were successfully amplified. Three genotypes were found in HBV typing, including 46 cases of type B(83.64%), 7 cases of type C(12.73%) and 2 cases of type D(3.63%). There were 15 cases of type B and 3 cases of type C in Guangxi; 10 cases of type B and 1 case of type C in Chongqing; 3 cases of type B, 1 case of type C and 1 case of type D in Luoyang; 15 cases of type B in Mianyang; 3 cases of type B, 2 cases of type C and 1 case of type D in Urumqi. The mismatch distribution of the HBVB type population with the largest population number showed a unimodal distribution, and the results of Tajima′s D test and Fu′s Fs test were both negative, indicating that the HBV population in these five regions was expanding. 【Conclusion】 The prevalent genotype of HBV in voluntary blood donors is type B, and the type B HBV population is experiencing a slow expansion, which should attract our attention. In the future, a thorough molecular epidemiological investigation of HBV should be carried out to ensure blood safety.
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Objective:To investigate the impact of multidisciplinary diagnosis and treatment on postoperative 30-day mortality and complications in elderly patients with hip fracture.Methods:A retrospective analysis was conducted of the 260 elderly patients with hip fracture who had been treated by the mode of multidisciplinary diagnosis and treatment at Department of Orthopedics, Shenzhen Second People's Hospital from June 2018 to October 2019. The multidisciplinary group consisted of 66 males and 194 females with an age of 78.7 years ± 5.1 years, and 141 femoral neck fractures, 114 intertrochanteric fractures and 5 subtrochanteric fractures. They were compared with the 242 elderly patients with hip fracture (traditional group) who had been treated by the traditional mode from January 2017 to May 2018. The 2 groups were compared in terms of preoperative waiting time, 48-hour operation rate, 30-day mortality, and incidences of postoperative pneumonia and pressure ulcer.Results:There were no statistically significant differences in the preoperative general data or operative procedures between the 2 groups, showing comparability ( P>0.05). For the multidisciplinary group, preoperative waiting time was 41.9 h ± 36.5 h, significantly shorter than that for the traditional group (71.4 h ± 13.9 h), 48-hour operation rate 66.5% (173/260), significantly higher than that for the traditional group(8.7%, 21/242), incidence of postoperative pneumonia 3.1%(8/260), significantly lower than that for the traditional group(9.9%, 24/242), incidence of postoperative pressure ulcer (5.4%, 14/260), significantly lower than that for the traditional group(11.2%, 27/242), and 30-day mortality(2.3%, 6/260), significantly lower than that for the traditional group(5.8%, 14/242) (all P<0.05). Conclusions:Establishment of a mode of multidisciplinary diagnosis and treatment can significantly reduce the prolonged preoperative waiting time for elderly patients with hip fracture, thereby greatly reducing postoperative complications and postoperative 30-day mortality.
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Objective To investigate new methods of osteonecrosis of femoral head (ONFH) with retrospective analysis of the clinical cases with technique of rotary cutting pressure-relief,impacted graft,and tantalum rod supporting treatment of early-stage femoral head necrosis.Methods From June 2010 to June 2014,32 cases (38 hips,23 males and 9 females) with ONFH were treated with technique of rotary cutting pressure-relief,impacted graft,and tantalum rod supporting,with the mean age of 24 ～ 52 (36.2 ± 3.8) years old.According to the Association Research Circulation Osseous (ARCO) classification,there were 11 hips on Ⅱ A stage,12 hips Ⅱ B,8 hips Ⅱ c,7 hips Ⅲ A.The averaged Harris score of all cases was 65 ～ 81 (72.5 ± 5.8) points.All cases were cured with minimally invasive technique,rotary cutter pressure-relief in femoral head,thoroughly remove sequestrum and implant allogeneic bone.Postoperative patients laid in bed for 1 month,after 1 month hold crutch gradually began to functional training.Postoperative 1 month,X ray film was reviewed every 3 months.According to the clinical symptoms,imaging findings,Harris scoring system was graded to evaluate the effectiveness.Results All the cases were followed up for average of 12 ～32 (20.2 ± 2.6) months,31 hips Kept hips succeed,hips pain; lame line symptoms were reduced or disappeared; x-ray showed femoral head necrosis area formed new bone,Harris scoring was upgraded to 75 ～ 95 (87.7 ± 6.4) points ; and seven hips failed with operation of total hip arthroplasty.The overall good rate was promoted from 26.3％ to 84.2％.Conclusions The technique treating for early-stagefemoral head necrosis with minimally invasive,rotary cutting pressure-relief,impacted graft,and tantalum rod supporting had a good short-term effects.
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Objective To investigate the effects of nitric-oxide synthase inhibitor on matrix metalloproteinases (MMPs) expression in osteoarthritis (OA) cartilage by Luminex analysis,and to explore the mechanism of nitric-oxide synthase inhibitor on modification of the metabolism of OA cartilage.Methods Fifteen specimens of articular cartilage taken from the patients with OA were cultured and divided in two groups.The control group was those with no intervention.L-NIL group was co-cultured with NOS inhibitor L-NIL.After 72 h cultivation,the release of NO and the activity of NOS on OA cartilage were measured by Griess reaction and spectrophotometric methods.MMPs (MMP-1,MMP-2,MMP-3,MMP-9,MMP-13) expression was measured by Luminex analysis.Comparisons between groups were performed with paired sampies t test.Results After cultured for 72 h,spectrophotometric analysis showed high concentration of NO release[(216±47) μmol/L ] and high level of active NOS [(5.7±1.3)U/ml]in supernatants of the control,1 mmol/L concentration L-NIL could evidently reduce NO release [(55±20)μmol/L,P<0.01] and NOS activity [(1.7±0.7)U/ml,P<0.01 ].Luminex analysis demonstrated high MMP-1,MMP-2,MMP-3,MMP-9,MMP-13 expression in cartilages of the control group [respectively for (10.8±5.4)ng/ml,(9.2±3.3) ng/ml,[11.6±4.2 )ng/ml,(1.27±1.07)ng/ml,(3.6±1.3)ng/ml] and 1 mmol/L concentration L-NIL could evidently inhibit MMP-1,MMP-2,MMP-3,MMP-9,MMP-13 expression [respectively for (3.6±1.8)ng/ml,(2.3±1.2)ng/ml,(3.6±1.4)ng/ml,(0.65±0.21)ng/ml,(1.8+0.5)ng/ml,P<0.05 ].Conclusion Luminex analvsis has shown that NOS inhibitor can reduce NO release and NOS activity and modify metabolism of articular cartilage by inhibiting the over-expression of MMPs.
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In this paper 12 cases of pigmented villonodular synovitis are reported, among which are 10 cases of knee joints, The clinic manifestations are mainly knee joint swelling pain, the function of the joints usually having no limitation. The liquor of blood colour or brown yellow colour is commonly pumped out through arthrocentesis. The shadow of soft tissue swelling could only be seen by X-ray. The X-ray examination 3 and therapy so on are mainly discussed in this paper. From therapy we stress the priority of completely synovium resection at early stage. During the operation one should do his best not to damage the patient's sport system muscle tendon. After the operation early dirigation is necessary.