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1.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
2.
保留骨骺灭活再植术治疗儿童股骨远端骨肉瘤   总被引:4,自引:3,他引:1  
[目的]探讨保留骨骺灭活再植术的临床应用注意事项及并发症的防治。[方法]回顾6年间所治疗的11例患者,男5例,女6例。平均年龄7.6岁。均位于股骨下端。MRI分型:Ⅰ型7例,Ⅱ型4例。1例合并病理骨折。治疗方法均采用术前化疗2疗程 保留骨骺灭活再植手术 术后化疗。[结果]手术时间为3~4 h。术中出血量为300~500 ml。无血管、神经损伤。术后切口一期愈合,无切口感染及切口延迟愈合。11例获得随访10~72个月,患膝屈曲>110°3例,90°~110°3例,60°~89°4例,<60°1例。下肢等长4例,患肢较健侧短<2 cm 5例,2~3cm 2例。复发1例,转移2例,死亡3例,螺钉松动1例,灭活骨骨折1例。[结论]保留骨骺灭活再植术有利于术后功能恢复和肢体长度的保持;严格无瘤及无菌操作、彻底引流、适当延长外固定的时间、功能锻炼时注意保护肢体等是预防并发症发生的主要措施。  相似文献   
3.
目的 为了检测人脑胶质瘤组织及胶质瘤细胞系LGI 1基因编码区中有无碱基突变及微卫星不稳定性(MSI)和杂合性缺失(LOH).方法 收集30例胶质瘤标本,2例脑膜瘤、2例瘤旁及2例颅脑损伤内减压脑组织标本及体外培养5个脑胶质瘤细胞系.提取组织标本及培养细胞基因组DNA.设计特异性引物分别扩增LGI 1各外显子序列,采用SSCP银染分析;扩增LGI 1微卫星序列,凝胶电泳银染分析;发现异常泳动条带进行DNA序列分析.结果 ①PCR-SSCP分析琼脂糖凝胶电泳检测有1例Ⅱ级胶质瘤标本未检测到第1 a外显子处扩增产物以及Ⅱ、Ⅲ级各1例胶质瘤标本均未检测到第8 c外显子处扩增产物.未在30例胶质瘤标本和4个脑胶质瘤细胞系中检测到电泳条带异常,在细胞系TJ905第5外显子处检测到电泳条带异常,经DNA测序分析证实确有突变.②在30例胶质瘤标本及5个细胞系中均未检测到MSI和LOH.结论 基因突变及MSI和LOH可能不是LGI 1在胶质瘤恶性进展过程中失活的主要原因.  相似文献   
4.
Type 1, 2, and 3 vaccine-derived polioviruses were isolated from a sewage disposal plant located downstream of the Oyabe River in Toyama Prefecture, Japan, between October 1993 and September 1995. Neurovirulence was analyzed in 13 type 1 vaccine-derived strains, using mutant analysis by polymerase chain reaction and restriction enzyme cleavage (MAPREC). Nine strains (69%) were estimated to have marked neurovirulence. Some of the neutralizing antigenic sites, temperature sensitivity, and plaque-forming ability of two virulent vaccine-derived poliovirus strains were similar to Mahoney strain. The neutralizing activity of human sera obtained after oral poliomyelitis vaccine (OPV) administration against one of the virulent vaccine-derived polioviruses was examined. Although all human sera showed sufficient neutralizing activity for the prevention of poliomyelitis by vaccine-derived poliovirus strains, a lower titer than that against Sabin type 1 strain was observed. Vaccination against virulent vaccine-derived poliovirus will be effective. However, the environmental presence of viruses that have properties similar to those Mahoney strain is a threat. The introduction of inactivated poliovirus vaccine (IPV), and well-maintained herd immunity, together with reinforced environmental surveillance is important for the final phase of the polio eradication program by the World Health Organization (WHO).  相似文献   
5.
Purification of bovine conglutinin using pepsin digestion   总被引:6,自引:0,他引:6  
This paper describes a new method for the purification of bovine conglutinin based on the relative resistance of this protein to pepsin digestion. First, conglutinin is purified by absorption on yeast, then the preparation is treated with 2% pepsin (w/w) at 4°C for 18 hr, and finally gel filtrated on agarose A5m. The yield is 60–75% and conglutinin thus prepared appears physically, immunochemically and functionally intact. This procedure allows for a rapid production of sufficient amounts of conglutinin for immune complex detection or purification methods.  相似文献   
6.
An autoradiographic method combined with a rosette technique was used to assess the bactericidal activity of individual control and inflammatory peritoneal macrophages (PM phi) in the presence or absence of expression of Fc receptor for IgG (FcR). There was a lack of FcR reactivity in a certain percentage of both categories of PM phi exposed to E. coli X43, a bacterium which is readily phagocytosed in the presence of specific antibody. Both rosetting and non-rosetting PM phi were capable of phagocytosing E. coli X43, but inflammatory PM phi showed a marked reduction in their capacity to ingest these bacteria compared with control PM phi. Once ingested the E. coli X43 were killed equally well by non-rosetting and rosetting control and inflammatory PM phi.  相似文献   
7.
甲型肝炎灭活疫苗不同免疫方案对恒河猴免疫效果观察   总被引:2,自引:0,他引:2  
目的 确定甲型肝炎灭活疫苗免疫恒河猴最佳免疫方案。方法 根据3个免疫方案(方案1:0周免疫;方案2:0周初次免疫、4周加强免疫;方案3:0周初次免疫、24周加强免疫),将17只抗-HAV阴性的恒河猴随机分成4组;第1组;免疫方案1;第2组:免疫方案2;第3组:免疫方案3。1~3组各5只,空白对照组2只。用同等剂量(1280EL.U/ml)的甲型肝炎灭活疫苗于上臂三角肌内分别免疫两组恒河猴,检测恒河  相似文献   
8.
灭活前后HIV-1包膜基因变异的研究   总被引:1,自引:1,他引:0  
目的 深入了解HIV在灭活因素作用下包膜基因变异。方法 对HIV-1B3亚型毒株在S/D法及低pH法灭活作用前后的样品,套式PCR扩增其民膜基因C2 ̄C3区564bp的核酸自段,进行核苷酸序列测定和分析。结果 两种方法活前后,包膜基因变异均不显著,核苷酸同源性均为98%。结论 S/D法及低pH法灭活作用前后HIV包膜基因变异不显著。体外传代HIV包膜基因趋于稳定。  相似文献   
9.
The purpose of this study is to investigate the production of both severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-specific antibodies and autoantibodies in serum following the third booster vaccination of the inactivated COVID-19 vaccine, and to study the effect of B cell subsets with CD27 and CD38 phenotypes in peripheral blood on antibody production. Routine blood indexes, SARS-CoV-2 antibodies, platelet factor 4 and seven antiphospholipid antibodies were detected both before and 2 months after vaccination in the medical staff of the Zhongnan Hospital of Wuhan University. Peripheral blood B cell subtypes were detected before vaccination. Following immunization, the positive rate of anti-N-S1 immunoglobulin (IgG) had increased from 24.8% to 91.3% and the average antibody concentration had increased by 11 times. The positive rate of neutralizing antibody had increased from 24.8% to 91.3%, the average antibody concentration had increased by 12 times, and the primary increased anti-S1 IgG subtype was that of IgG1. Peripheral blood CD27 + CD38+ B cells were positively correlated with antibody levels after vaccination and were a predictor of the antibody response. In addition, although some indicators showed slight absolute changes, the blood parameters and antiphospholipid antibodies of most volunteers were normal both before and after COVID-19 inactivated vaccine inoculation, and there was no statistical difference in abnormal rates either before or after inoculation. Antibodies in vivo were increased after vaccination with the inactivated vaccine, and IgG1 was the main subtype involved in response to the vaccine. Vaccination with the inactivated COVID-19 vaccine did not appear to affect thrombus-related autoantibodies.  相似文献   
10.
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