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Objective:To investigate various clinical treatment measures for thoracolumbar fractures and provide new diagnosis and treatment methods.Methods:The case data of 5 patients(3 males, 2 females, and the age ranged from 39 to 59 years with an average of 51 years) with thoracolumbar fractures were treated with Waveflex semi-rigid internaI fixation system from May 2020 to December 2021 were retrospectively analyzed, imaging indexes and clinical effects were followed up, and analyzed and summarized in combination with relevant literatures.Results:The operations of all 5 patients were successfully completed, and the follow-up period was 6 months. At the last follow-up, the internal fixation position was good, the height of the injured vertebra was maintained satisfactorily, and the clinical effect was satisfactory.Conclusion:Waveflex semi-rigid internal fixation system combines the advantages of fusion and non-fusion, providing a new idea for the treatment of thoracolumbar fractures, but its long-term effect still needs further follow-up.
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Osteoporotic vertebral compression fracture(OVCF) will bring heavy economic and medical burden to patients, families and society, which has become an increasingly serious clinical and social problem, the clinical should pay great attention to it. Although the minimally invasive method of diagnosis and therapy of OVCF, which is the most common type of osteoporosis fracture (fragility fracture or low-energy traumatic fracture), has been widely developed, it is urgently needed to receive bone mineral density examination and accept standardized treatment for patients with osteoporosis. This article will focus on the crucial diagnosis and therapy problems and the latest progress of spinal OVCF, looks forward to the future development trend, and provides reference for the standardized clinical diagnosis and therapy of OVCF.
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With the introduction and development of the concept of precision surgery,3D printing individualized guide template has been gradually applied in the field of spinal surgery because of its advantages of increasing surgical precision,reducing the difficulty and risk of surgery,reducing the operation time,and reducing the intraoperative transmission dose,etc..Individualized guide plates designed and manufactured according to the patient~ surgical site,self-conditions and individual differences before surgery can accurately restore the preoperative design during surgery to meet the needs of modernized spine surgery for individualization and precision.Individualized guide template has great guiding significance for complex spinal surgery.This article reviews the current clinical application of 3D printing individualized guide template in spine surgery,summarizes its produce principles and procedures,advantages and limits,and make prospect for it's future applications.
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Objective To investigate whether capsular polysaccharides of Streptococcus pneumoniae serotypes 6A and 6B contained in 13-valent pneumococcal conjugate vaccine ( PCV13 ) could induce cross- protective antibodies against newly discovered serotypes 6C and 6D and the differences between them. Methods New Zealand rabbits were radomly divided into three groups and respectively muscularly administrated with three doses of PCV13, PCV6A and PCV6B on days 0, 14 and 28. PCV6A and PCV6B were conjugates of capsular polysaccharides of serotypes 6A and 6B chemically coupled with diphtheria toxin mutant CRM197. Serum samples were collected on days 0 and 35. Enzyme-linked immunosorbent assay (ELISA) recommended by World Health Organization (WHO) was used to quantitatively measure serotype-specific antibodies to capsular polysaccharides of serotypes 6A, 6B, 6C and 6D. Opsonophagocytosis assay ( OPA) of WHO pneumococcal serology reference laboratory was used to determine antibody functional activities targeting serotypes 6A, 6B, 6C and 6D. Results Immunization rabbits with PCV13 induced the secretion of antibodies to capsular polysaccharides of serotypes 6A and 6B. These antibodies were able to not only cross-react with capsular polysaccharides of serotypes 6C and 6D but also recognize and bind to target Streptococcus pneumoniae serotypes 6A, 6B, 6C and 6D, resulting in the activation of complements and further phagocytosis of target bacteria by differentiated HL60 cells. Bactericid-al titers were largely even among these serotypes except for serotype 6D which was slightly lower. PCV6A could induce antibody against capsular polysaccharide of serotype 6A, which was able to cross-react with capsular pol-ysaccharides of serotypes 6B, 6C and 6D and showed higher bactericidal titers to serotypes 6A, 6B and 6C over serotype 6D. PCV6B could induce antibody against capsular polysaccharide of serotype 6B, which was able to cross-react with capsular polysaccharides of serotypes 6A, 6C and 6D and showed higher bactericidal titers to se-rotypes 6A, 6B and 6C over serotype 6D. Antibody concentrations and bactericidal titers specific to serotypes 6A, 6B, 6C and 6D were significantly increased following immunization with PCV13, PCV6A or PCV6B (P<0. 01). Conclusion PCV13 containing pneumococcal serotypes 6A and 6B induced antibodies against capsular polysaccharides of serotypes 6A and 6B in New Zealand rabbits, which were able to cross-react with capsular polysaccharides of serotypes 6C and 6D and provide cross-protection to bacteria of serotypes 6C and 6D. Both serotypes of 6A and 6B contained in PCV13 contributed to the induction of cross-protective antibodies, especially to serotype 6C.
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Objective To establish an animal model for evaluating immunogenicity of pneumococcal conjugate vaccine.Methods New Zealand rabbits were intramuscularly administrated with three doses of 13-valent pneumococcal conjugate vaccine (PCV13) with two weeks interval between each injection.Serum samples were collected at different time points before and after vaccination.Quantitative enzyme-linked immunosorbent assay (ELISA) and opsonophagocytosis assay (OPA) that were in conformity with the World Health Organization (WHO) standards were used to detect the concentrations of serotype-specific antibodies and their bactericidal activities.Results The concentrations (Geometric mean concentration, GMC) of serotype-specific antibodies in rabbit serum samples were well correlated with their bactericidal activities (Geometric mean titer, GMT) following vaccination.Moreover, the dynamic changes of GMC and GMT of the same serotype-specific antibody remained consistent as time went by.Conclusion Rabbit model can be used to analyze the immunogenicity of PCV13 vaccine with quantitative ELISA and OPA, which indicates that it is a suitable animal model for evaluating immunogenicity of pneumococcal conjugate vaccine.
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Objective To re-evaluate the immunogenicity of meningococcal serogroups A and C polysaccharide vaccine among a healthy population of age 5 to 59.Methods Pre and post-vaccination ser-um samples were collected from the subjects involved in a randomized , controlled clinical trial conducted in 2005 at Hechi, Guangxi, China.Enzyme-linked immunosorbent assay (ELISA) was performed for the quan-titative detection of specific anti-capsule IgG antibody against meningococcal serogroups A and C in serum samples.Serum bactericidal assay ( SBA) was used to measure the bactericidal antibody activity against se-rougroups A and C bacterial strains .Results Geometric mean concentrations (GMCs) of specific anti-cap-sule IgG antibody were 23.66 μg/ml and 78.83 μg/ml for serogroup A (P0.05).The percentage of serum sam-ples with serogroup C-specific IgG concentration ≥2 μg/ml rose from 20%to 99% after vaccination ( P0.05), and from 14%to 96%for serogroup C (P<0.05) after vaccination.The rSBA GMTs with at least four times of in-creases after vaccination were detected respectively in 53% and 100% of serogroups A and C vaccinated subjects.Pearson correlation coefficient between IgG concentration and rSBA GMTs was r=0.15 (pre) and r=0.23 (post) for serogroup A, and r=-0.14 (pre) and r=0.58 (post) for serogroup C (P<0.05). Conclusion This study has demonstrated an efficient and sustained immunogenicity with meningococcal sero -groups A and C polysaccharide vaccine as evidenced by the data from standardized assays of ELISA and SBA .
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Objective To dynamically analyze the antibodies with regard to in vitro serum bacteri-cidal activity and the quantity of IgG in healthy adults received one dose of immunization with ACYW 135 me-ningococcal polysaccharide vaccine .To investigate the term of protection with polysaccharide vaccine and the correlation between bactericidal titer and IgG concentration .Methods Twenty healthy adults were given one dose of immunization with quadrivalent meningococcal polysaccharide vaccine .Serum samples were col-lected before and after vaccination at specific time points .Test for serum bactericidal activity ( SBA ) and quantitative ELISA were performed to detect bactericidal titers and IgG concentrations in serum samples .Re-sults Certain levels of antibodies against capsular polysaccharides of serogroup A , C, Y and W135 strains had already existed prior to immunization .Moreover, bactericidal titers against serogroup A , Y and W135 strains except serogroup C strain were relatively high .Specific IgG concentrations and bactericidal titers for all serogroup stains were significantly increased on day 15 after vaccination (P0.05).However, a close correla-tion was demonstrated between GMTs and GMCs of serum samples (r>0.7, P<0.05).Conclusion The geometric mean titers ( GMTs) and geometric mean concentrations ( GMCs) of serum samples collected be-fore and after vaccination at different time points were reliable and consistent parameters for the evaluation of vaccine .The term of protection of quadivalent meningococcal polysaccharide vaccine was about 3 years upon a single dose of immunization .
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Objective To prepare a human meningococcal reference serum and standardize IgG concentrations to capsular polysaccharides and in vitro bactericidal activities of the reference serum against serogroup A, C, Y and W135 strains.Methods Twenty healthy adults were recruited and given one dose of immunization with tetravalent (serogroups A, C, Y and W135) meningococcal polysaccharide vaccine . Plasma samples were collected and gone through a series of process treatments including defibrination , filtra-tion, and lyophilization to prepare the meningococcal reference serum Men 10.The IgG concentrations of Men10 to capsular polysaccharides of serogroups A , C, Y and W135 were calibrated by using an internation-al reference serum CDC1992 as the standard in enzyme-linked immunosorbent assay (ELISA).Provisional IgG concentrations of Men10 were intensively validated by testing a panel of 12 calibration serum samples from Centers for Disease Control and Prevention , USA ( US CDC) and a panel of 56 serum samples immu-nized with A, C, Y and W135 meningococcal polysaccharide vaccine from Lanzhou Institute of Biological Products Co., Ltd.(LIBP) with the assays using Men10 and CDC1992 as the standard and/or test sam-ples, respectively.The bactericidal titers against serogroup A , C, Y and W135 strains were measured by se-rum bactericidal assay (SBA).Results Four thousand vials (0.5 ml/vial)of lyophilized human meningo-coccal reference serum Men10 were successfully prepared with 2.5%of residual moisture .Reference serum Men10 was sterile and free from contamination by hepatitis B virus , hepatitis C virus , human immunodefi-ciency virus and syphilis .Provisional IgG concentration of Men 10 to capsular polysaccharide of serogroups A, C, Y and W135 was calibrated by using CDC1992 as the standard.Furthermore, IgG concentrations of both panels of 12 CDC calibration serum samples and 56 LIBP serum samples calibrated by using Men 10 as the standard correlated well with those by using CDC1992 as the standard (r=0.99,P<0.05).The IgG concentrations of CDC1992 as calibrated by using Men10 as the standard showed significant correlation with its previously determined values with variation <10%.SBA titers for serotype A , C, Y and W135 strains were established as well .Conclusion A panel of new human meningococcal reference serum Men 10 with accurately calibrated IgG concentration against capsular polysaccharide of serogroups A , C, Y and W135 as well as SBA titers was successfully established .
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Objective To establish a standardized quantitative enzyme-linked immunosorbent as-say ( ELISA) recommended by WHO for the detection of human IgG antibodies specific for Streptococcus pneumoniae capsular polysaccharides ( Pn PS ELISA ) .Methods According to the WHO recommended standard Pn PS ELISA protocol , capsular polysaccharide concentrations of 13 serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F) of Streptococcus pneumonia for coating were optimized;the ELISA plates and AP conjugated goat anti-human IgG antibody for the detection were experimentally selected .Using the established assay parameters assured by testing quality control standards ( QCs) provided by WHO refer-ence laboratory , a panel of 16 LIBP ( Lanzhou Institute of Biological Products Co .Ltd.) QCs were measured for comparison analysis between WHO reference laboratory and LIBP laboratory .In the meantime , the range of IgG concentrations of an internal QC panel 907 for 13 serotypes of pneumococcal capsular polysaccharide were established for routine QC work in LIBP laboratory , and inter-assay precision within LIBP laboratory was assessed as well .Results The standardized Pn PS ELISA assay established in LIBP laboratory met the criteria required by WHO .There was a high correlation between the data collected by WHO reference labora -tory and LIBP laboratory (slope=0.94, coefficient of correlation r=0.97, P<0.05).Eighty one percent of IgG concentrations measured by LIBP laboratory were within the range of ±40%of those measured by WHO reference laboratory , which met the criteria of 75%data falling within the ambit of ±40%of assigned values commonly used for comparison .The ranges of IgG concentration in LIBP QC 907 for 13 serotypes had been established.The inter-assay precision in LIBP laboratory was high with coefficiency of variation ( CV) less than 30%.Conclusion LIBP laboratory has successfully established the standardized ELISA recommended by WHO for quantitative detection of human IgG antibodies against pneumococcal capsular polysaccharides (Pn PS ELISA).The range of IgG concentrations in LIBP QC 907 for 13 serotypes of pneumococcal capsular polysaccharide are also established for routine quality-control practice .