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排序方式: 共有337条查询结果,搜索用时 31 毫秒
51.
Nirmal Marasini 《Drug development and industrial pharmacy》2019,45(6):882-894
Pulmonary infections are the most common cause of death globally. However, the development of mucosal vaccines that provide protective immunity against respiratory pathogens are limited. In contrast to needle-based vaccines, efficient vaccines that are delivered via noninvasive mucosal routes (such as via the lungs and nasal passage) produce both antigen-specific local mucosal IgA and systemic IgG protective antibodies. One major challenge in the development of pulmonary vaccines using subunit antigens however, is the production of optimal immune responses. Subunit vaccines therefore rely upon use of adjuvants to potentiate immune responses. While the lack of suitable mucosal adjuvants has hindered progress in the development of efficient pulmonary vaccines, particle-based systems can provide an alternative approach for the safe and efficient delivery of subunit vaccines. In particular, the rational engineering of particulate vaccines with optimal physicochemical characteristics can produce long-term protective immunity. These protect antigens against enzymatic degradation, target antigen presenting cells and initiate optimal humoral and cellular immunity. This review will discuss our current understanding of pulmonary immunology and developments in fabricating particle characteristics that may evoke potent and durable pulmonary immunity. 相似文献
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Caroline Morris Sarah J. Glennie Hon S. Lam Holly E. Baum Dhinushi Kandage Neil A. Williams David J. Morgan Derek N. Woolfson Andrew D. Davidson 《Advanced functional materials》2019,29(8)
Subunit vaccines use delivery platforms to present minimal antigenic components for immunization. The benefits of such systems include multivalency, self‐adjuvanting properties, and more specific immune responses. Previously, the design, synthesis, and characterization of self‐assembling peptide cages (SAGEs) have been reported. In these, de novo peptides are combined to make hubs that assemble into nanoparticles when mixed in aqueous solution. Here it is shown that SAGEs are nontoxic particles with potential as accessible synthetic peptide scaffolds for the delivery of immunogenic components. To this end, SAGEs functionalized with the model antigenic peptides tetanus toxoid632‐651 and ovalbumin323‐339 drive antigen‐specific responses both in vitro and in vivo, eliciting both CD4+ T cell and B cell responses. Additionally, SAGEs functionalized with the antigenic peptide hemagglutinin518‐526 from the influenza virus are also able to drive a CD8+ T cell response in vivo. This work demonstrates the potential of SAGEs to act as a modular scaffold for antigen delivery, capable of inducing and boosting specific and tailored immune responses. 相似文献
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Microalgae is becoming a promising candidate for biofuel production and energetic lipid production, which urges the need to develop efficient methods for improvement of the lipid production. In this study, the neutron irradiation was employed to improve lipid production under different dosage irradiation. Effects of different dosages (No.1:8.14 × 109, No.2:5.64 × 108, No.4:9.42 × 107 n/cm2) were compared by investigating associated algae cell growth, total lipid production, metabolization and enzyme activity. Dosages No.2 and No.4 improved the lipid content without negative influence on the growing, whereas irradiations shortened the period of biomass accumulation. The neutron irradiation in No.2 accelerated the synthesis of lipid from the carbohydrate transition process. In addition, the neutron irradiation not only increased the total lipid production by 20% but also speeded up the reaction rate to reach the maximal total lipid production in 28 days. Our results can provide a better understanding of the lipid production in microalgae Chlorella sp. by neutron irradiation, which are critical for evaluation of neutron irradiation based technologies for the sustainable and renewable biofuel production. 相似文献
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pRL-hTNF/JM103工程菌发酵和rhTNFα表达的研究 总被引:2,自引:0,他引:2
为便于下游中试规模生产,采用温度敏感型启动子PRPL构建rhTNFα工程菌,并对影响工程菌发酵培养和表达的因素进行了初步研究。结果显示,采用RTB培养基,50℃热水快速升温,诱导培养4~4.5h,湿菌体收获率和表达量均达到较高水平;50L发酵罐连续发酵3批,14000r/min连续离心,菌体收获率湿重达16.gg/L培养物,rhTNFα表达量占菌体总蛋白的10.5%,活性达1.35×107U/mg蛋白。. 相似文献
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H.S. Fang C. Zhang Departmentof Materials Science Engineering Tsinghua University Beijing China 《金属学报(英文版)》1999,12(4):315-321
1.IntroductionDuringlastseveraldecadesmuchachievementshasbeenobtainedonbainitetransformationbymanyscientists,butsomedisagreementsonbainitetransformationmechanismstillremain〔14〕.Thefollowingreviewsummarizestherecentinvestigationsonbainitetransformati… 相似文献
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Claudia Fecher-Trost Karin Wolske Christine Wesely Heidi Lhr Daniel S. Klawitter Petra Weissgerber Elise Gradhand Christine P. Burren Anna E. Mason Manuel Winter Ulrich Wissenbach 《International journal of molecular sciences》2021,22(23)
Recently, we reported a case of an infant with neonatal severe under-mineralizing skeletal dysplasia caused by mutations within both alleles of the TRPV6 gene. One mutation results in an in frame stop codon (R510stop) that leads to a truncated, nonfunctional TRPV6 channel, and the second in a point mutation (G660R) that, surprisingly, does not affect the Ca2+ permeability of TRPV6. We mimicked the subunit composition of the unaffected heterozygous parent and child by coexpressing the TRPV6 G660R and R510stop mutants and combinations with wild type TRPV6. We show that both the G660R and R510stop mutant subunits are expressed and result in decreased calcium uptake, which is the result of the reduced abundancy of functional TRPV6 channels within the plasma membrane. We compared the proteomic profiles of a healthy placenta with that of the diseased infant and detected, exclusively in the latter two proteases, HTRA1 and cathepsin G. Our results implicate that the combination of the two mutant TRPV6 subunits, which are expressed in the placenta of the diseased child, is responsible for the decreased calcium uptake, which could explain the skeletal dysplasia. In addition, placental calcium deficiency also appears to be associated with an increase in the expression of proteases. 相似文献