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【Objective】 To explore the HBV infection of initially reactive but discriminatory test non-reactive (NAT suspicious) samples of voluntary blood donors after PANTHER individual nucleic acid testing (ID-NAT) in Tianjin. 【Methods】 From January to August 2021, after routine testing and PANTHER ID-NAT, a total of 66 HBsAg-NAT reactive but discriminatory test non-reactive samples(referred to as NAT suspicious samples) were tested from 69 362 blood samples. Among which, 23 samples were selected by simple random sampling method and enriched by ultra-high speed centrifugation. HBV DNA was detected by supersensitive fluorescence quantification PCR (qPCR)and ID-NAT, and electrochemiluminescence was supplemented for two and half pairs of hepatitis B detection. 【Results】 Among 23 suspicious NAT samples, 14 were confirmed HBV DNA positive by serological and molecular biological tests, and the anti-HBc positive rate of HBV infected individuals was 92.8%. 92.8% (13/14) of the infected individuals were occult hepatitis B virus infection(OBI). A total of 10 samples were detected for viral load by qPCR, of which 5 were quantifiable, with viral load of (11~464) IU/mL and a median of 15.4 IU/mL. 【Conclusion】 60% of the NAT suspicious samples were detected as HBV DNA positive. Anti-HBc testing can exclude most OBI undetectable by NAT, and the sensitivity of NAT should be improved to ensure the safety of blood transfusion.
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【Objective】 To investigate the HBV infection of TMA initially reactive but discriminatory test non-reactive samples(NDR) after the individual donation nucleic acid detection(ID-NAT)of TMA, and analyze its serological and molecular biological characteristics, so as to improve the safety of blood transfusion. 【Methods】 121 970 samples of blood donors in the center from January 1, 2021 to December 31, 2021 were routinely tested by serology and nucleic acid of ID NAT, and 21 HBsAg(-)/ NDR samples were random collected. After the plasma samples were concentrated by ultra-high speed centrifugation, the gene sequences of BCP/PC, pre-S/S and S region were amplified by Nested PCR. The S region sequence was also sequenced to analyze the viral genotype and amino acid variation. At the same time, the original TMA retest discriminatory test was adopted, and Roche MPX 2.0 was used for ID-NAT, and the samples was not virus-concentrated.NDR samples were supplemented with electrochemiluminescence for anti-HBc and anti-HBs quantitative detection. 【Results】 Of the 121 970 samples screened, 117(0.096%) were found to be HBsAg(-)/NDR samples, of which 21 samples underwent a confirmation test. Sixteen(76.2%) cases were positive for HBV DNA by TMA retest, 7(33.3%) positive for HBV DNA by Roche MPX 2.0 ID-NAT, 9(42.9%) confirmed by Nested PCR, and 8(38.1%) positive by any two methods. Test results of serological markers were as follows: 17(80.9%) positive anti-HBc and 8(38.1%) positive anti-HBs. Eight infected cases were confirmed to have occult hepatitis B infection(OBI). The gene sequence of S region was successfully amplified and sequenced in 3 cases, all of which belonged to C type. Two mutations occurred in specimen S-2, all of which were outside MHR. There were 13 mutations in sample S-6, 6 mutations outside MHR and 7 mutations inside MHR. 【Conclusion】 Nearly 40% of NDR samples can still be detected as HBV DNA positive after virus concentration. Anti-HBc has a high detection rate, and there may be a potential risk of HBV transmission. The current NAT detection sensitivity should be improved. The amino acid mutation of S gene sequence may be related to OBI formation.
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【Objective】 To establish deferral criterion of HIV ELISA (enzyme-linked immunosorbent assay) and electrochemiluminescence immunoassay(ECLIA) by using receiver operating characteristic curve(ROC) method to screen HIV reactive blood donors suitable for entering the re-entry process and improve the management efficiency of reactive blood donors. 【Methods】 The test results of 92 001 blood donors from February to September 2019 were analyzed, and 177 reactive samples were screened by conventional screening mode (twice ELISA and once nucleic acid), supplemented with electrochemiluminescence immunoassay assay (ECLIA), and confirmed by Western blotting (WB). Screening reactive samples were divided into three groups: group A was both serological and nucleic acid reactivity, group B was only serological reactive, and group C was only nucleic acid reactivity. Its efficacy in blood donor classification was assessed by drawing ROC curves with 99% specific corresponding S/CO low values as the deferral criterion of the corresponding serological method. 【Results】 1) A total of 177 HIV reactive samples were detected in conventional mode, including 34 in group A, 142 in Group B and 1 in Group C. The positive predictive value (PPV) was 100%, 0.75% and 100%, respectively. ECLIA detection mode (once ECLIA and once NAT), a total of 67 HIV reactive samples including 34 in group A, 32 in group B and 1 in group C, with positive predictive values of 100%, 3.7% and 100%, respectively.2) The HIV test results showed diversity, with 36 true positive samples including 1 HIV elite controller and 3 early HIV infections (1 HIV ELISA antigen/antibody window and 2 ELISA HIV antibody window), and 32 serological and NAT cases were reactive infections.3) The deferral limit of ELISA 1 and ELISA 2 in conventional screening mode were 20.25 and 9.85, respectively, can screen 97.14% (34/35) of all true positive samples in group A and B, except for one ELISA HIV antibody window (ELISA 2 reactivity). The positive predictive values were 93.94% and 92.85%, respectively. The ECLIA deferral limit of 7.83 can screens all true positive samples in Groups A and B (35/35)in ECLIA mode. The positive predictive value was 94.59%. 【Conclusion】 The establishment of deferral limits in this study can effectively screen HIV-positive blood donors, and the number of screened blood donors is greatly reduced, which is helpful to fine and scientific management of HIV-reactive blood donors. The deferral limit values of different testing reagents are quite different, so each laboratory should choose appropriate testing methods to establish the deferral limit values suitable for the laboratory according to its own testing ability, so as to provide technical support for optimizing the process of returning blood donors to the team.
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【Objective】 To perform electrochemiluminescence immunoassay (ECLIA) and Western blotting (WB) confirmation tests for HIV reactive samples in blood screening, and analyze the correlation between ELISA (enzyme-linked immunosorbent assay), ECLIA results and confirmed infection, so as to provide data support for the application of ECLIA in blood screening. 【Methods】 177 HIV reactive samples in blood screening testing detected by our laboratory from February to October 2019 were collected, of which 137 were reactiv to isolated ELISA reagent e, 39 to dual ELISA reagent, and 1 in window period. Ten maker-negative samples were randomly selected to undergo ECLIA with the above 177 samples. HIV reactive samples were sent to Centers for Disease Control and Prevention (CDC) for confirmation tests, and the results were analyzed and compared. 【Results】 Among the 177 HIV reactive samples, 66 were ECLIA reactive, 111 negative, and the 10 maker-negative samples remained negative. The sensitivity, specificity, positive predictive value, negative predictive value and total concordance rate of ECLIA were 97.1%, 81.1%, 55%, 99.1% and 84.2%, respectively, showing better performance than that of two ELISA reagents(P0.05). The positive predictive value and specificity were tested by chi-square test, and the difference between ECLIA and reagent 2 was statistically significant (P<0.05). The ECLIA results showed significant correlation with the confirmation results with good consistency(examed by Kappa test). Among the three reagents, ECLIA presented highest accuracy and largest Youden index. 【Conclusion】 ECLIA presents high detection sensitivity, which can improve the detection ability of early HIV infection and shorten the window period of HIV detection, therefore should be popularized in blood screening.
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Objective To analyze the physicochemical properties and photothermal properties after introducing a certain proportion of phaeophorbide into polyvinyl alcohol-lipoic acid polymer.Methods The "one-step" method was adopted to synthesize the PVA27K-4 ％LA-10 ％ Pheide (PLP) polymer.The laser particle diameter tester was used to detect the particle size,polydispersity index and ζ potential of PLP nanoparticle (PLPN);the morphology was observed under transmission electron microscope (TEM);the in vitro fluorescent and photothermal properties were investigated by using spectrophotometric method and infrared thermal imager;the ovarian-cancer nude mice models were established and the preliminary in vivo experiment evaluation was performed.Results The synthetic PLP polymer could self-assembly form spherical PLPN in aqueous environment,which showed the tightly spherical structure under TEM.The average particle diameter,polydispersity index and ζ potential were (22.92 ± 9.00)nm,(0.117±0.056) and (-25.43±0.77)mV respectively.The fluorescence intensity of PLPN in PBS solution was significantly lower than that in SDS solution (P＜0.05).However,the temperature of the PBS solution of PLPN was significantly higher than that of the SDS solution after exposure to the near infrared light (P＜0.05).In the model of tumor-bearing nude mice,PLPN could targetaccumulated in the tumor site.The temperature in the tumor site was significantly increased after exposure to the near infrared light,which could kill tumor cells.Conclusion PLPN could emit red fluorescence,and could target-accumulated in tumor site and conduct the in vivo image,which has significant photothermal conversion properties in vivo and in vitro,and can effectively inhibit the tumor growth in vivo.
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Objective To discuss the detail design of medical linear accelerator room to optimize the layout of radiation shield.Methods According to the optimization principle for medical exposure protection and national radiation protection related documents,the influence of detail design on room quality was analyzed.Optimization design was executed from theaspects of spatial layout,protection,shielding wall,decorating materials,labyrinth,control cabin,protective door,occupancy factor,purification ventilation,tennperature humidity control and etc.Results The design and layout of the roomwere optimized to eliminate hidden risksand reduce the design flaws to prevent adverse consequences due to design errors.Conclusion Detail design contributes to stable operation,enhanced quality and efficiency of medical linear accelerator room.
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Protein phosphorylation in bacteria is important for signaling and metabolic activity. Clostridium acetobutyicum can synthesize high yield of organic solvent under acidic condition. How solventogenesis is regulated at molecular level in this bacterium, is not clearly elucidated yet. We used two dimensional electrophoresis (2-DE) and mass spectrometry to have a differential analysis of the bacterial proteins from Clostridium acetobutylicum at acedogenic and solventogenic stage. We focused on these iso-spots with similar molecular mass and different pI values. Totally, eight string spots were identified, which displayed significant changes of pI values as well as spot volumes in response to solventogenic development. The data acquired from mass spectrometry demonstrated that all of the iso-spots contained the phosphrylated peptides. Bioinformatic analysis revealed that these proteins partake in the pathways of solvent synthesis.
Subject(s)
Bacterial Proteins , Metabolism , Clostridium acetobutylicum , Genetics , Metabolism , Electrophoresis, Gel, Two-Dimensional , Mass Spectrometry , Phosphorylation , Proteome , Proteomics , MethodsABSTRACT
Objective To explore the value of lymphatic mapping (LM) and sentinel lymph node(SLN) analysis in laparoscopic colectomy for colon carcinoma. Methods Thirty-two patients with clinically localized colonic neoplasms were subjected to submucosal injection of isosulfan blue dye (0.5-1.0 mL) via a colonoscope during operation. Blue-stained lymphatics were visualized through the laparoscope and followed to the SLN,which was tagged. The colectomy was completed in standard fashion. All lymph nodes were stained by hematoxylin and eosin,and multiple sections of each SLN were examined by immunohistochemical (IHC) staining using cytokeratin antibody. Results At least one SLN was identified laparoscopically in all patients. The SLN accurately predicted the tumor status of the nodal basin in 94% of cases. In 8 cases (25%),an unexpected lymphatic drainage pattern altered the extent of mesenteric resection. The SLN was negative by HE staining in 4 (13%) cases,which were demonstrated positive for micrometastases through immunohistochemical staining. Conclusions SLN mapping during laparoscopic colon resection can alter the margins of resection and in combination with immunohistochemical staining may improve staging,which may more accurately assign patients to prospective protocols.
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Objective To evaluate the method and outcome of surgical treatment for refractory slow-transit constipation (STC). Methods Clinicopathologic data of 24 patients with severe STC which underwent (colectomy) in recent years were retrospectively analyzed. Results 18 of the patients underwent pancolectomy,and 6 underwent subtotal colectomy. All of the 14 STC patients complicated with outlet obstructive (constipation)(OOC) were corrected preoperatively by related surgery. The curative rate of surgical (treatment) was 95.8%,with an average of(3?1.9) times of bowel motion per day. The incidence of (abdominal) distention decreased from 75% to 12.5%. One patient who underwent ileorectal anastomosis (developed) recurrent constipation. Conclusions Colectomy produces satisfactory results in the majority of (patients) with refractory slow-transit constipation.Patients complicated with OOC should undergo energetic (preoperative) correction therapy,in order to ensure a satisfactory surgical outcome.