Performance verification and comparison of TianLong automatic hypersensitive hepatitis B virus DNA quantification system with Roche CAP/CTM system.

AIM: To investigate and compare the analytical and clinical performance of TianLong automatic hypersensitive hepatitis B virus (HBV) DNA quantification system and Roche CAP/CTM system. METHODS: Two hundred blood samples for HBV DNA testing, HBV-DNA negative samples and high-titer HBV-DNA mixture samples were collected and prepared. National standard materials for serum HBV and a worldwide HBV DNA panel were employed for performance verification. The analytical performance, such as limit of detection, limit of quantification, accuracy, precision, reproducibility, linearity, genotype coverage and cross-contamination, was determined using the TianLong automatic hypersensitive HBV DNA quantification system (TL system). Correlation and Bland-Altman plot analyses were carried out to compare the clinical performance of the TL system assay and the CAP/CTM system. RESULTS: The detection limit of the TL system was 10 IU/mL, and its limit of quantification was 30 IU/mL. The differences between the expected and tested concentrations of the national standards were less than ± 0.4 Log10 IU/mL, which showed high accuracy of the system. Results of the precision, reproducibility and linearity tests showed that the multiple test coefficient of variation (CV) of the same sample was less than 5% for 102-106 IU/mL; and for 30-108 IU/mL, the linear correlation coefficient r2 = 0.99. The TL system detected HBV DNA (A-H) genotypes and there was no cross-contamination during the "checkerboard" test. When compared with the CAP/CTM assay, the two assays showed 100% consistency in both negative and positive sample results (15 negative samples and 185 positive samples). No statistical differences between the two assays in the HBV DNA quantification values were observed (P > 0.05). Correlation analysis indicated a significant correlation between the two assays, r2 = 0.9774. The Bland-Altman plot analysis showed that 98.9% of the positive data were within the 95% acceptable range, and the maximum difference was -0.49. CONCLUSION: The TL system has good analytical performance, and exhibits good agreement with the CAP/CTM system in clinical performance.

Age and Ebola viral load correlate with mortality and survival time in 288 Ebola virus disease patients.

BACKGROUND: A Chinese medical team managed Ebola virus disease (EVD) patients in Sierra Leone from October 2014 to March 2015 and attended to 693 suspected patients, of whom 288 had confirmed disease. METHODS: A retrospective study was conducted of the 288 patients with confirmed disease. Clinical symptoms, manifestations, and serum viral load were analyzed and compared among the different groups for mortality and survival time. RESULTS: Among the 288 confirmed EVD patients (149 male and 139 female, median age 28 years, and median log viral load 6.68), 98 died, 36 recovered, and 154 were lost to follow-up. Common symptoms were fever (77.78%), fatigue (64.93%), abdominal pain (64.58%), headache (62.85%), and diarrhea (61.81%). Compared to patients aged<18 years, those who were older than 40 years had a higher probability of death (odds ratio 2.855, p=0.044). Patients with a viral load of >10(6) copies/ml had a higher case fatality rate than those with <10(6) copies/ml (odds ratio 3.095, p=0.004). Cox regression showed that age, viral load, and the presence of diarrhea correlated with mortality. CONCLUSION: Patients with a high viral load, of older age, and with diarrhea had a higher mortality and shorter survival time.

[A clinical and pathological analysis of 22 cases of primary sclerosing cholangitis].

OBJECTIVE: To characterize the clinical, laboratory, imaging and pathological features of primary sclerosing cholangitis (PSC) and investigate the impact of ursodeoxycholic acid (UDCA) therapy on patient prognosis. METHODS: The medical records of 22 patients diagnosed with PSC between 2002 and 2011 were retrospectively reviewed. The PSC diagnosis had been made in patients with suspect biochemical abnormalities following evaluation by magnetic resonance cholangiopancreatography (MRCP) and/or endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC). Fibrosis and inflammation were assessed by immunohistochemical analyses of tissue biopsies. Outcome of patients treated with UDCA (13-15 mg/kg/day, oral) were compared to that of patients without UDCA treatment by the X2 or corrected X2 tests. RESULTS: Among the 22 PSC patients, the majority was male (n=15) and presented with fatigue, dark urine, and body weight loss (n=15). Four cases had ulcerative colitis. At admission, all 22 cases showed elevated levels of alkaline phosphatase[ALP: (348+/-184) U/L], 19 cases showed elevated alanine aminotransferase [ALT: (94.0+/-67.0) U/L] and aspartate aminotransferase [AST: (98.0+/-67.0) U/L], and 15 cases showed elevated levels of total bilirubin (99.0+/-115.0) mumol/L and direct bilirubin (74.4+/-92.4 mumol/L. ERCP examination showed segmental intrahepatic bile duct stenosis with expansion, and stiff and enlarged gallbladder bile ducts, but unclear findings for the common bile ducts and pancreatic ducts. MRCP showed beading of the intrahepatic bile duct, stiffness of the bile duct wall, and dilation of the common bile duct. Fibrosis and inflammation were observed in the bile ducts, along with hyperplasia and the typical features of "onion skin" fibrosis and fibrous obliterative cholangitis. Five of the 10 patients treated with UDCA improved, and seven of the 12 patients in the non-UDCA treatment group improved. There was no statistically significant difference in outcome between the groups (paired X2=0.333, corrected X2=0.083, P more than 0.05). CONCLUSION: PSC patients were predominantly male and the common clinical manifestations were fatigue, dark urine, and body weight loss. At admission, serum biochemical indicators of cholangitis were increased significantly and subsequent imaging studies confirmed the suspected diagnosis by showing obvious characteristic changes. UDCA treatment did not significantly improve patient prognosis.

[Distribution of genotypes in ESBLs producing E. coli strains isolated from posthepatitic cirrhosis' patients with bloodstream infection].

OBJECTIVE: To study the genotype distribution of extended-spectrum beta-lactamases (ESBLs) in ESBLs-producing Escherichia coli (E. coli) isolates from posthepatitic cirrhosis' patients with bloodstream infection. METHODS: E. coli were isolated in bloodstream from patients with posthepatitic cirrhosis between January and December in 2011. The strains were identified by VITEK-II. The antibiol susceptibility tests were performed with K-B method. beta-lactamases genes were detected multi-PCR, PCR, sequence and blast. RESULTS: A total of 79 non-duplicate clinical isolates of E coli were consecutively collected from liver cirrhosis' patients with bloodstream infection. There were 20 isolates produced TEM-1 type beta-lactamases and 1 isolate produced SHV-1 typebeta-lactamases. 40 clinical isolates were detected to produce CTX-M type ESBLs, there were 20 CTX-M-1 group and 26 CTX-M-9 group, including 6 stains habouring both CTX-M-1 and CTX-M-9 group. Eight CTX-M genotypes were confirmed by sequencing of the PCR products, including CTX-M-3, CTX-M-14, CTX-M-15, CTX-M-24, CTX-M-28, CTX-M-31, CTX-M-65 and CTX-M-79. CONCLUSION: CTX-M genotype ESBLs was the most popular extended-spectrum beta-lactamases in E. coli isolated from liver cirrhosis' patients with bloodstream infection. The CTX-M-14 is the dominant epidemic type.

[Establishment of a quantitative detection method for Golgi protein73].

OBJECTIVE: To establish enzyme-linked immunosorbent assay (ELISA) for quantitative detection of Golgi protein73 (GP73) in serum. METHODS: A sandwich reaction was preformed with horseradish peroxidase labeled monoclonal antibody of GP73 as the catalytic enzyme. Several reactions liquid's concentration and reaction conditions were optimized. The method was evaluated in all aspects such as linear range, sensitivity, specificity, stability and so on. RESULTS: The linear range was 25-500 ng/ml. The detection limit was 18.5 ng/ml. Inter-assay and intra-assay RSD were both less than 10%. The recoveries of three different spiked concentration samples were 95.3%, 92.6% and 103.7%. After stored at 4 degrees C and 37 degrees C for 3, 5, 7 days, the analysis showed correlation coefficient higher than 0.98 and RSD lower than 10%. CONCLUSION: Established ELISA for quantity determination of serum GP73 has high accuracy, sensitivity and repeatability.

[The early diagnosis value of EV 71 IgM class antibodies in the hand, foot and mouth disease].

OBJECTIVE: Assessment of detection of IgM antibodies for human enterovirus 71 (EV 71) in early diagnosis for the hand, foot and mouth disease (HFMD). METHOD: The sera and throat swabs from 38 patients which were clinical diagnosis as HFMD, were continuous daily collected in our hospital in 2010. These specimens were detected by EV 71 IgM antibodies assay, real time RT-PCR methods for EV 71 and Enterovirus. RESULTS: Among 38 HFMD patients, the cumulative positive rates of EV 71 IgM antibodies were: 60.5% on day 1, 71.1% on day 2, 81.5% in the first 3-4 days, 92.1% on day 5, 92.1% on day 6, and the positive rate of nucleic acid detected by the real time RT-PCR for EV 71 and Enterovirus were 60.5%, 73.6%. CONCLUSION: The positive rate of EV 71 IgM antibodies in the hand, foot and mouth disease just can occur on day 1, and reach to peak on day 5, which can be used as one of indicators of early diagnosis of hand, foot and mouth disease.

[The verification of a new DNA double-detection diagnostic kit for identifying novel influenza A (H1N1)].

OBJECTIVE: To verify a new kit of "universal and novel influenza A (H1N1) virus nucleic acid double-detection methods (PCR-fluorescence probe)". METHODS: 150 cases of throat swab specimens were collected consecutively. After RNA was extracted, the specimens were detected by the verified kit. At the same time, the same specimens were detected by Real-time PCR diagnostic kit from Beijing CDC as the control. The data were analysed by the Kappa in agreement and by McNemar chi2 in difference test. RESULTS: The consistency rate of the verified kit and the Beijing CDC kit was universal primer M 97.33%, H1N1 98.67% respectively. The Kappa test and McNemar chi2 test showed that two methods had a higher consistency. Compared to the CDC kit, the "false negative rate" and "false-positive rate"of double-check kit were lower. CONCLUSION: The kit of "universal and novel influenza A (H1N1) virus nucleic acid double-detection methods (PCR-fluorescence probe)" from Shanghai Kehua Bio-Engineering Co., Ltd can be used to detect influenza A and novel influenza A (H1N1).

Immunologic changes during Pandemic (H1N1) 2009, China.

We analyzed changes in immunologic values over time for 28 hospitalized patients with pandemic (H1N1) 2009. Levels of interleukin-6, interferon-y, and interleukin-10 increased 1 day after illness onset and then decreased to baseline levels. Levels of virus-specific antibody were undetectable 1 day after illness onset and peaked 36 days later.

[Clinical and laboratory characteristics of a new influenza A (HIN1) epidemic].

OBJECTIVE: To analysis the clinical and laboratory characteristics of Patients infected with new influenza A (HIN1) virus. METHODS: All cases with new influenza A (H1N1) confirmed on polymerase chain reaction assay on throat swabs. There were included in a prospective evaluation of clinical characteristics, laboratory results, treatment and overcome of new influenza A (H1N1). RESULTS: There were 35 patients in the epidemic. Clinical illness developed within a mean of 1.7 days. Fever occurred in 97.1%, sore throat 65.7% cough 51.4%, headache 28.6%, and myalgia 31.4%. All patients were treated with oseltamivir lasted 5 days. The mean duration of viral shedding was 4.5 days. All were cured and left hospital after day 7. CONCLUSION: It was infected by new influenza A (H1N1) typically in this epidemic.

[The distribution and antimicrobial resistance tendency of pathogens associated with diarrhea in Beijing].

OBJECTIVE: To monitor the constituents and resistant tendency of bacterial pathogens isolated from diarrheal patients in our hospital form 1994 to 2005 to offer the basis for guiding epidemiologic study, vaccination research and clinical treatment. METHODS: Enteric pathogenic bacteria were cultured and identified to species, group and serotype with biochemical and serologic methods and the susceptibility of bacteria to antimicrobial agents were tested. RESULTS: Enteric pathogenic bacteria were isolated predominantly in male patients and mainly in children and youngsters. It reached a peak from July to September every year. Shigella spp. (75.11%) was the most frequently isolated pathogens and followed by Vibrio spp. (12.7%), Salmonella spp. (6.28%), Aeromonas spp. (4.43%) and Escherichia coli (1.25%). During the period from 1994 to 2005, diarrheal pathogens had a trend of decrease especially Shigella spp. and Salmonella spp. Of the 6329 isolates of Shigella spp., 75.62% was S. flexneri and S. sonnei, S. dysenteriae and S. boydii constituted 23.98%, 0.22% and 0.01% respectively. The sensitivity of different species, group or serotype to different antimicrobial agents was not the same. S. flexneri and Aeromonas spp. were highly resistant to most of antibiotics. However, S. sonnei and Vibrio spp. had good susceptibility to antibiotics tested except trimethoprim/sulfamethoxazole and ampicillin. CONCLUSION: There are many species and serotypes of enteric pathogenic bacteria causing infective diarrhea and the distribution changes gradually in Beijing. The resistance rate of enteric pathogenic bacteria to antibiotics is not the same in different species and serotypes, so strict surveillance is always needed.

[Detection of multiresistance Aeromonas with TEM type resistant genes in patients with cirrhosis].

OBJECTIVE: To study the status of beta-lactamase produced by multiresistant Aeromonas selected from cirrhosis patients to provide reference for treatment and reduce resistance and control spreading. METHODS: Four multiresistant Aeromonas strains isolated from serious liver cirrhosis patients from the No. 302 hospital. The TEM resistant genes were detected by PCR and agarose gel electrophoresis. RESULTS: Three TEM-1 positive strains were detected from four multiresistant Aeromonas isolates consisting of one Aeromonas sobria and three Aeromonas hydrophila isolated from blood and ascites. This was further confirmed by gene sequencing. The multiresistance to antibiotics was higher in four Aeromonas isolates. All strains tested were resistant to ampicillin, cefazolin and cefmetazole.The cirrhosis patients who suffered from Aeromonas infection had poor prognosis and had mortality rate of 3/4. CONCLUSION: The beta-lactamase TEM-1 resistant genes was detected in clinical multiresistant Aeromonas strain isolated from serious cirrhosis patients.The results suggested that TEM-1 was the main resistance mechanism of Aeromonas strain and was reduced by adding enzyme inhibitor.

[Immunopotency of the recombinant urease B subunit vaccine of Helicobacter pylori after intranasal administration to mice].

AIM: To observe the immunopotency of the recombinant urease B subunit (rUreB) of Helicobacter pylori after intranasal administration to mice. MDTHODS: BALB/c mice were immunized intranasally with rUreB of 20 microg,10 microg and rUreB plus different adjuvants, such as cholera toxin B subunit (CTB), Escherichia coli heat labile enterotoxin B subunit (LTB) and carbopol respectively, four times at an intervals of 7 days. The serum and washing solution from gastric, intestinal, nasal and tracheal mucosas were collected in 7 days after final immunization. IgG and IgA antibodies specific for rUreB were detected by ELISA. RESULTS: The levels of IgA and IgG antibodies in sera every groups of mice immunized intranasally were significantly increased compared with control group (P<0.01). Only the levels of serum IgG of mice immunized with 20 microg dose were higher than those of mice immunized with 10 microg dose. Carbopol could enhance the level of IgA antibodies in washing solution from mouse gastric mucosa after intranasal immunization. The efficacy of LTB as a nasal mucosal immuno-adjuvant was stronger than that of CTB. CONCLUSION: CTB, LTB and carbopol can play the role of adjuvant in nasal mucosal immunization. Intranasal immunization with rUreB can induce not only serum IgG antibody production but also antibody responses of different mucosa. Thus intranasal inoculation is a convenient, effective and cheap immunization way.