ABSTRACT
【Objective】 To determine the ELISA kit for screening convalescence plasma with high potency of SARS-CoV-2 IgG by comparing and analyzing the plasma detection results of convalescent plasma collected in different periods via ELISA kits from two manufacturers and the results of mixed plasma with different potency via pseudovirus neutralization experiments. 【Methods】 Two ELISA kits from different manufacturers(named A, B) were used to detect the plasma of 269 convalescent patients collected from Feb.2020~Jan.2022. The correlation and concordance rate of the two results were analyzed to determine the kit preliminarily. According to the titers of diluted series of standard of the preliminary selected kit, 5 mixed plasma samples (G4-G128) with different potency were prepared. The correlation of ELISA IgG results of product A/B, as well as the pseudovirus neutralization test of the original strain, Omicron mutant BA.1 and BA.2 strains were analyzed. Combined with the outside-well dilution mode of the strongly positive samples, the kit for high potency of SARS-CoV-2 IgG screening was determined. 【Results】 When the internal control reference B2 was used as the standard, the detection sensitivity of product A and B was 1∶32 vs 1∶8; the detection sensitivity of product A was 4 times that of product B. The correlation Pearson r between the results given by two kits was 0.944 1(P<0.000 1). Product B with low sensitivity was primarily selected as an alternative kit. The ELISA IgG results of samples from mixed plasma showed that the order of correlation r between product A and B was 0.988. The correlation r between product A and neutralization antibody potency of the three viruses was original strain (0.978)>BA.2(0.970)>BA.1(0.799); the order of correlation r between ELISA IgG results of product B and neutralization antibody potency of the three viruses was original strain(0.994)>BA.2(0.968)>BA.1(0.804). If twice-diluted B2 was taken as the excellent standard, 55.4% of product B met the criterion, while 47.2% of product A met.For positive plasma with high IgG potency, the product B kit required a lower dilution of the sample, which was more convenient to operate. 【Conclusion】 Both of the ELISA IgG kit from product A and B can be used to screen IgG antibodies of SARS-CoV-2, while product B is more suitable for screening positive plasma with high IgG potency.
ABSTRACT
【Objective】 To determine the best collection time period of plasma which can be used for human COVID-19 immunoglobulin for intravenous injection through SARS-CoV-2-IgG change and neutralizing antibody distribution against different virus strain in representative mixed plasma before and after Omicron strain infection by ELISA and pseudovirus neutralization test. 【Methods】 An ELISA method for quantitative detection of SARS-CoV-2-IgG was established and its linear range,accuracy and precision was verified. SARS-CoV-2-IgG potency was detected in 25 convalescent plasma which were collected 20-40 days after confirmed Omicron infection, two groups of mixed plasma samples WP1 and WP2 were prepared according to the SARS-CoV-2-IgG results, and pseudovirus neutralization experiments with different virus strain (prototype strain, BA. 1,BA.2, BA.4/5, BF.7, BQ.1.1) were carried out to determine the distribution of neutralizing antibodies against different virus strain. SARS-CoV-2-IgG potency of representative mixed plasma collected from 14 plasma stations subordinate to the company before and after Omicron strain infection was detected, including Omicron convalescent plasma (OP) collected from different plasma stations from December 2022 to May 2023 and normal pool plasma (VN) feed in March 2023 which collected from March 2022 to December 2022. According to the results, the difference and the change rule with time of SARS-CoV-2-IgG before and after Omicron strain infection were analyzed. 【Results】 The linearity of SARS-CoV-2-IgG ranged from 6.25 to 200 EIU/mL, the accuracy in-batch ranged from 81.793% to 106.985%, the precision in-batch ranged from 1. 100% to 13.000%, and the total error in-batch ranged from 2.988% to 22.679%. The accuracy between batches ranged from 90.788%to 96.893%, the precision between batches ranged from 4.870% to 6.272%, and the total error between batches ranged from 9.192% to 15.399%. The results of pseudovirus neutralizing antibody showed that the potency of different virus strain neutralizing antibodies were in the order of prototype strain>BA.2>BA.4/5>BF.7≈ BQ.1.1>BA.1 and the correlation between WP1 and WP2 was high (Pearson r=0. 931 1, P=0.002 3) which indicated that the potency distribution of neutralizing antibodies of different virus strain in Omicron convalescent plasma was basically stable. Compared with the mixed convalescent plasma sample G128 collected in June 2022, the potency of Omicron neutralizing antibodies of WP series were significantly higher, the ratio of BA.2 antibody to prototype antibody increased from 26.9% (before infection) to 82.6%-87.5% (after infection). The results of VN series before Omicron infection were < 100 EIU/mL, and the results of OP series after Omicron infection showed that the plasma collected from the beginning of December 2022 was the peak of antibody in the same month,and then dropped sharply, entering a short plateau in February-March 2023 (potency was about 40% of the peak value),and then dropped sharply again in April (potency was about 20% of the peak value). 【Conclusion】 The potency and proportion of neutralizing antibody against Omicron subtype in convalescent plasma after COVID-19 Omicron strain infection increased significantly. IgG antibody of plasma donors in different regions reached its peak in the month of infection, then continued to dropped sharply. The best collection period of plasma that can be used for human COVID-19 immunoglobulin for intravenous injection was 1 to 2 months after infection.
ABSTRACT
PURPOSE: Our aim is to compare 3-dimensional mesh fixation using titanium tacks combine with n-butyl cyanoacrylate glue (NBCG) (COMBINE group) versus NBCG only (NBCG group) in totally extraperitoneal inguinal hernioplasty (TEP). METHODS: This is a retrospectively study of patients diagnosed with unilateral inguinal hernia and underwent TEP with 3-dimensional configured polyester mesh fixation using titanium tacks combine NBCG or NBCG only at the University of Hong Kong-Shenzhen Hospital with data prospectively collected. Operative details and outcomes were compared including: operating time, size of defect, total hospital cost, post-operative pain scores and recurrence. RESULTS: From 08.2013 to 03.2016 a total of 219 patients were included. There was no significant difference between COMBINE group and NBCG group in mean age (52.5 years versus 48.2 years), mean size of defects (2.4 cm versus 2.6 cm), and operating time (121 mins versus 111 mins). There were significant differences between COMBINE group and NBCG group in total hospital cost (3035 USD versus 2022 USD), post-operative pain score on day 2 to day 4 (VAS: 1.4 versus 1.0, 1.0 versus 0.4, 0.5 versus 0.2). There was one recurrence in COMBINE group (p=0.276) with overall recurrence of 0.46%. CONCLUSION: Patients with inguinal hernia underwent TEP with 3-dimensional configured polyester mesh with NBCG fixation only having comparative surgical outcome to COMBINE group. A recurrence of 0.46% can be achieved with this combination. Tacks fixation may cause more post-operative pain and increase hospital cost. Use of N-butyl cyanoacrylate glue in TEP is safe and effective in our clinical series.
Subject(s)
Humans , Adhesives , Cyanoacrylates , Hernia, Inguinal , Herniorrhaphy , Hospital Costs , Polyesters , Prospective Studies , Recurrence , Retrospective Studies , TitaniumABSTRACT
Repair of lower abdominal incisional hernia is always a surgical challenge. TAPE technique has been described for the repair of supra-pubic midline incisional hernia with satisfactory outcome. Its indication can be extended for treatment of non-midline lower abdominal hernia. Peritoneal incision is created just below the hernia defect with pre-peritoneal dissection to expose supra-pubic preperitoneal space with Cooper's ligament exposed. Non-adhesive mesh then placed over preperitoneal space and partially intra-peritoneally, and cover the whole extra-peritoneal space prepared to ensure enough overlapping. Mesh is fixed by tackers for intra-peritoneal part, most inferior fixation points were at peritoneal incision line. Extra-peritoneal part of meshes is fixed at the safety zone and covered up by the peritoneal flap to avoid mesh migration. Fixation of the meshes at the lateral aspects were facilitated by the peritoneal flap and subsequent fibrosis and adhesion to the extra-peritoneal structures in cases of lateral lower abdominal hernia. Repair of midline and lateral lower abdominal incisional hernia with this novel modified technique with prosthetic mesh is safe and effective. A larger case series and longer follow-up is required for validation of this technique.
Subject(s)
Fibrosis , Follow-Up Studies , Hernia , Hernia, Abdominal , Hernia, Ventral , Incisional Hernia , LigamentsABSTRACT
OBJECTIVE: To prepare Biyanling nasal drops and establish a method for its quality control.METHODS: Biyanling nasal drops was prepared with ephedrine hydrochloride and chlorpheniramine maleate etc,and an HPLC method was established for the determination of chlorpheniramine maleate and ephedrine hydrochloride in Biyanling nasal drops.RESULTS: The Biyanling nasal drops were yellow emulsion and in line with the related standard specified in Chinese Pharmacopeia(2005 Edition) in identification and tests.The linear ranges of ephedrine hydrochloride and chlorpheniramine maleate were 0.210～2.096(r=0.999 8)?g?mL-1 and 79.6～796.0(r=0.999 9)?g?mL-1,respectively,and the average recoveries of ephedrine hydrochloride and chlorpheniramine maleate were 98.83%(RSD=1.45%) and 99.19%(RSD=1.37%),respectively.CONCLUSION: The preparation of nasal drops is feasible in technique,stable and controllable in quality.
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To investigate the influence of six exogenous pathogenic factors on asthma in children and to observe the changes of microscopic indexes in cold- and heat-type asthma. Logistic regression analysis was applied to analyze the influence of six exogenous pathogenic factors and the changes of serum level of IgE, eosinophil (EOS) counting, contents of third component of complement (C3) and C-reactive protein (CRP) were observed. The exogenous factors of wind, cold, damp, wind-cold mixture and cold-damp mixture were the risky factors of asthma. Serum levels of IgE and EOS were higher in cold-type asthma and serum contents of C3 and CRP were higher in heat-type asthma (P