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《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
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目的:检测诱导型和内皮型一氧化氮合酶(iNOS 和eNOS)在外阴慢性单纯性苔藓和外阴硬化性苔藓中的表达。方法:采用免疫组织化学SABC法检测iNOS和eNOS在30例外阴慢性单纯性苔藓蜡块(LSC)、30例外阴硬化性苔藓蜡块(LS)和10例外阴正常皮肤中的表达,并以人原始造血细胞抗原(CD34)标记微血管内皮细胞,测量各组织的微血管密度(MVD)。结果:iNOS和eNOS在外阴正常皮肤中无表达;在LSC中iNOS和eNOS每视野平均阳性细胞数分别为14.83±3.79和17.86±4.82,高于LS的8.00±3.35和6.43±3.87,差异均有统计学意义(P<0.05);在LSC和正常皮肤中MVD分别为21.58±2.48和20.44±3.66,高于LS(10.34±2.83)。iNOS和eNOS的表达具有明显的正相关性(Kappa=0.811,P<0.05)。结论:iNOS和eNOS可能与LSC炎症过程中的血管扩张有关;在LS皮损真皮中微血管减少,iNOS和eNOS可代偿性地改善LS的血液循环。 相似文献
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目的分析研究绝经后女性2型糖尿病伴骨质疏松症患者骨密度与骨代谢指标的相关性。方法选取2013年10月至2017年05月于重庆医科大学附属第一医院内分泌内科住院的绝经后女性2型糖尿病患者385名。搜集其基本资料、骨代谢指标及骨密度等。根据T值将这些患者分为骨质疏松组(233例)、骨量减少组(101例)和骨量正常组(51例),比较三组间骨代谢指标的变化,并对骨密度(bone mineral density,BMD)与各项骨代谢指标进行相关性分析。结果 1型前胶原氨基末端前肽(Type I procollagen N-terminal propeptide,P1NP)、骨钙素(bone Gla protein,BGP)在骨质疏松组显著高于骨量减少组、骨量正常组(P0.05);随着骨密度的降低,1型胶原羧基端肽β特殊序列(β-Carboxyl terminal peptide,β-CTX)逐渐升高,骨质疏松组、骨量减少组与骨量正常组相比较差异有统计学意义(P0.05);Spearman等级相关分析示P1NP、BGP、β-CTX与骨密度呈负相关,25(OH)D_3与骨密度呈现正相关。结论绝经后女性2型糖尿病伴骨质疏松症患者骨密度与骨代谢指标有一定的相关性,有助于预测骨折风险并及时抗骨质疏松治疗。 相似文献
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Wang Kai Jiang Yanrong Li Xiaoxin 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(9):1152-1159
Background Intravitreal triamcinolone acetonide (TA) has been widely used as a therapeutic method for many ocular diseases, but a consensus on an appropriate safe therapeutic window of dosage for intravitreal injection, and whether vehicle of TA should be reduced or eliminated, has not yet been reached. The aim of this article is to investigate these issues.Methods Forty New Zealand white rabbits were divided into four experimental groups and one control group. Four or 25 mg TA, with vehicle either reduced or not, was injected into the vitreous cavity of rabbits in experimental groups. Rabbits in the control group received 0.2 ml intravitreal sterile saline solution. Intraocular pressures (IOP) were measured by a Tonopen tonometer. Values of lens density were measured by a Pentacam system. Soluble protein, total antioxidation capacity, reduced glutathione (GSH), glutathion peroxidase (GSH-px), and superoxide dismutase (SOD) in lens were measured by specific kits. ERG and pathological examinations, including light and electron microscopy of the retina, were also performed.Results Elevation of IOP was noted in all experimental groups after intravitreal TA (P<0.01, paired t-test). Significant increase of lens density was noticed at 1 week after intravitreal TA in the 25 mg vehicle-containing group (P<0.0001, paired t-test). Significant loss of GSH-px activity was noticed at the end of the study (P<0.05, paired t-test), while SOD activity increased (P<0.05, paired t-test). Amplitudes of ERG waves declined significantly in vehicle-containing groups (P<0.01, paired t-test) at the end of the study. Pathological examination showed obvious retinal toxicity in vehicle-containing groups.Conclusions Vehicle of TA should be eliminated or reduced before intravitreal injection to avoid potential retinal toxicity and transient increase in lens density.Presented at Chinese Academy of Fundus Disease Meeting, April, 2005.This study was supported by the 985 Fund of Peking University, Beijing.The authors have no financial interest in any instruments or drugs mentioned in this study. 相似文献
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目的:探讨血管生成、细胞增殖指数、DNA倍性在胰腺导管癌发生、发展中的作用及临床意义。方法:对29例胰腺导管癌和7例慢性胰腺炎患者的石蜡包埋标本作苏木精鄄伊红(HE)染色,CD34、Ki67免疫组织化学染色,镜下计算微血管密度(MVD)及Ki67阳性细胞比例,同时用流式细胞仪(FCM)检测细胞核DNA倍性,计算异倍体出现率及S期比例,并结合临床病理资料对各项指标作相关分析。结果:胰腺导管癌和慢性胰腺炎都有较多的新生血管。MVD值在胰腺导管癌高、中、低分化3组之间差异无显著性。按肿瘤直径分为≤1.5cm、1.6~2.9cm、≥3cm3组,此3组间MVD值、Ki67阳性细胞百分率、DNA异倍体出现率及肿瘤周围有无浸润的差异都非常显著(P<0.01)。肿瘤越大,MVD值、Ki67阳性细胞百分率及DNA异倍体出现率越高。结论:胰腺导管癌的发生、发展伴血管生成和DNA合成增加,联合测定MVD、Ki67阳性细胞百分率、DNA倍型可能为胰腺导管癌临床预后预测提供辅助参考指标。 相似文献
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带浅静脉干逆行皮瓣早期微血管构筑变化的体视学研究 总被引:4,自引:0,他引:4
目的 探讨带浅静脉干的逆行皮瓣早期微血管构筑变化的特点以供临床实践参考。方法 应用生物体视学技术测量带浅静脉干皮瓣微血管体积密度,结合组织学观察,与不带静脉干皮瓣作对照比较。结果 带浅静脉干皮瓣组微血管密度整体水平高于不带静脉干皮瓣组(P〈0.05)。结论 浅静脉干的存在有利于皮瓣的血管化进程,保留浅静脉干对皮瓣成活有利。 相似文献
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