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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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采用快速粘度分析仪(RVA)研究了食盐对18种普通玉米杂交种淀粉糊化性质的影响。结果表明:食盐显著降低了所有普通玉米杂交种淀粉的峰值、破损值和回生值;提高了谷值、终粘度、出峰时间和成糊温度。但对不同的普通玉米杂交种淀粉的糊化性质的影响程度有显著差别。随着食盐溶液质量分数的增加,普通玉米杂交种淀粉的谷值、终粘度、出峰时间和成糊温度也逐渐增加,破损值和回生值则显著降低,峰值受食盐溶液质量分数的影响很小。 相似文献
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Chemically distinct rat olivocochlear neurons. 总被引:6,自引:0,他引:6
We have produced a neurochemical map of the cell bodies of origin of the cochlear efferent terminals in rat by combining glutamic acid decarboxylase (GAD), choline acetyltransferase (ChAT), or calcitonin gene-related peptide (CGRP) immunocytochemistry with retrograde transport of horseradish peroxidase. The locations of cochlear efferent cell bodies are in general agreement with the medial and lateral systems described by White and Warr (J. Comp. Neurol. 219:203-214, 1983) with some minor modifications. The lateral system consists of at least two pools of chemically distinct neurons located within the lateral superior olive (LSO) ipsilateral to the injected cochlea. One pool immunostains with an antibody to GAD while the other immunostains with antibodies to ChAT and to CGRP. The medial efferent system consists of periolivary neurons that are almost exclusively large and ChAT-positive but CGRP-negative. They are located both ipsilateral and contralateral to the cochlea they project to. There are a few GAD-positive small neurons in the medioventral and rostral periolivary regions that project ipsilaterally, but these may prove tobe ectopic neurons. The ipsilateral lateroventral periolivary region (LVPO) contains some efferent neurons, all of which are ChAT-positive but CGRP-negative. Additional cochlear efferent neurons, some of which are ChAT-positive and others GAD-positive, are present within and immediately dorsal to the fiber capsule surrounding the medial limb, and to a lesser extent the lateral limb, of the ipsilateral LSO. Not all GAD-positive or ChAT-positive olivary cells project to the cochlea. We have complemented the results in the brainstem by demonstrating two immunocytochemically distinct populations of efferent terminals in the cochlea simultaneously, one CGRP-positive and the other GAD-positive. Approximately equal numbers of boutons immunoreactive for both markers are present beneath inner hair cells throughout the entire length of the cochlea. Surprisingly high numbers of GAD-positive and CGRP-positive boutons are also present on outer hair cells, with each class having its spatially and morphologically distinct features. The lack of CGRP-positive periolivary cells that are retrogradely labeled by cochlear injections of HRP suggests that the lateral olivocochlear system sends projections to outer hair cells. Our results raise questions about species differences in the organization of targets of the lateral and medial olivocochlear systems. 相似文献
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Despite the use of gold complexes in modern medicine for over 100 years and the use of gold complexes in the management of
rheumatoid disease for more than 60 years, the definitive mechanisms of action for efficacy and for toxicity have not been
established.
Gold is a group 1b metal in the periodic table with several oxidation states but it is only Au(I) which is active in the biological
milieu. Gold sodium thiomalate is not only a polymeric structure, but also has the chiral ligand, thiomalic acid. Gold sodium
thiomalate thus can exist in several different physical states which may have different biological activity. In addition the
pharmacokinetic profile of gold complexes has been of little value in the understanding of either the mechanism of action,
efficacy or toxicity for both the injectable and the oral gold complexes. Many authors have misinterpreted research data on
the activities of gold complexes because they compared gold complexes of different structures, and gold complexes which exist
at different pH.
Experimental work in our laboratory has identified that gold sodium thiomalate is a mixture and can exist as either a yellow
or a colourless solution. These have some similar but several different biological activities.
Many factors contribute to the lack of understanding of the action of gold complexes. Some of these factors are related to
the wide variation in physical structure and biological activities exhibited by these compounds. 相似文献
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E. Perucca R. Grimaldi G. Ruberto C. Gelmi F. Trimarchi A. Crema 《European journal of clinical pharmacology》1986,29(6):729-730
Summary The kinetics of phenobarbital (PB) was compared after oral administration of equivalent doses of the drug as the acid or the propylhexedrine salt (barbexaclone) to 7 normal volunteers. The absorption and elimination parameters were very similar. It was concluded that propylhexedrine did not affect the serum kinetics of PB given as barbexaclone. 相似文献
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WEIGUANG ZENG PIERRE-OLIVIER REGAMEY KEITH ROSE YUZHOU WANG ERNST BAYER 《Chemical biology & drug design》1997,49(3):273-279
The use of N, O-bisFmoc-N-(2-hydroxy-4-methoxybenzyl) amino acid derivatives in the synthesis of peptides with difficult sequences has already been described. With these amino acid derivatives the reversible protecting group 2-hydroxy-4-methoxybenzyl (Hmb) for the backbone amide bonds of peptide chains is introduced, and thus the aggregation due to hydrogen-bond interchain association is inhibited. This paper describes the synthesis and use of Fmoc-N-(2-hydroxy-4-methoxybenzyl)amino acid derivatives as an alternative means of introducing Hmb backbone protection. These new monoFmoc derivatives were obtained in higher yield than the bisFmoc derivatives. Coupling yields to the amino peptide resin were the same as those obtained with bisFmoc derivatives, under the TBTU/HOBt/DIEA conditions. We also compared different syntheses of a difficult peptide with the Fmoc approach [triple coupling, capping, use of chaotropic agents, backbone protection using monoFmoc (Hmb)Ala] and with optimized Boc chemistry. Both the backbone protection and optimized Boc chemistry approaches gave the desired product in excellent yield and purity. © Munksgaard 1997. 相似文献
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自身免疫性感音神经性聋豚鼠的子代内耳生理功能研究 总被引:4,自引:4,他引:0
目的 :观察自身免疫性感音神经性聋 (ASHL)母豚鼠所产子代内耳生理功能的变化 ,探讨针对内耳的自身免疫因素对子代内耳生理功能的影响及其改变特点。方法 :同种内耳抗原 (CIEAg)持续免疫孕豚鼠 ,采用耳蜗电图 (记录cAP、CM )和眼震电图仪 (记录自发性眼震和冷热空气试验 )测试母鼠和子鼠的听觉和前庭功能 ,并检测血清特异性体液免疫反应。结果 :ASHL模型母豚鼠所产子鼠血清中发现有特异性抗体水平升高 ,部分 (3 /9)出现听觉损伤。非ASHL母鼠和对照组母鼠所产子代未见明显异常。结论 :ASHL雌鼠所产子代可出现感音神经性聋 ,其内耳损伤和功能障碍极可能与针对内耳组织的自身免疫反应 (尤其是体液免疫 )有关 ,从而提示内耳自身免疫因素可能为部分先天性非遗传性感音神经性聋的病因之一。 相似文献