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Modified and synthetic α‐amino acids are known to show diverse applications. Histidine, which possesses numerous applications when subjected to synthetic modifications, is one such amino acid. The utility of modified histidines varies widely from remarkable biological activities to catalysis, and from nanotechnology to polymer chemistry. This renders histidine residue an important place in scientific research. Histidine is a well‐studied scaffold and constitutes the active site of various enzymes catalyzing important reactions in the biological systems. A rational modification in histidine structure with a distinctly developed protocol extensively changes its physical and chemical properties. The utilization of modified histidines in search of potent, target selective and proteostable scaffolds is vital in the development of bioactive peptides with enhanced drug‐likeliness. This review is a compilation and analysis of reported side‐chain ring modifications at histidine followed by applications of ring‐modified histidines in the synthesis of various categories of bioactive peptides and peptidomimetics. [ABSTRACT FROM AUTHOR]

Box‐Behnken design was applied for the development of a novel, precise, simple, and accurate high‐performance thin‐layer chromatography method for simultaneous estimation of mentioned drugs in the formulation. Optimization was performed using Quality by Design. Principles of risk assessment followed by application of design for optimization of chromatographic conditions to determine critical parameters: volume of hexane, chamber saturation time, solvent front and their effects on critical method attributes: Rf values of both drugs. Optimized conditions were determined through Derringer's desirability approach of the multi‐criteria decision‐making technique. Good resolution using optimized mobile phase, hexane:ethyl acetate:ammonium acetate in methanol (5.1:3:2) with Rf values 0.34 and 0.67 for Ivabradine Hydrochloride and Carvedilol, respectively, was obtained. The method was validated as per International Council on Harmonization having a linear range of 1000–5000 ng/band of Ivabradine and 1250–6250 ng/band for Carvedilol, respectively. %Recovery was in range of 99.23–101.3 and 99.8–100.5, respectively. Precision and robustness were found to be in an acceptable range. Thus, Quality by Design based method development assisted in making design space with knowledge of all method performance characteristics with a better understanding of high‐performance thin‐layer chromatography. The Analytical GREEnness profile was assessed using AGREE tool with an overall reliable score of 0.68. [ABSTRACT FROM AUTHOR]

Radiation attenuated sporozoite (RAS), a whole‐parasite vaccine approach, provides sterile protection against malaria. However, RAS immunization does not confer protection for long, and that has been correlated with the waning parasite–induced memory CD8+ T‐cell responses. Interestingly, an intermittent infectious (wild type) sporozoite challenge to the RAS‐vaccinated mice lengthened the protection period from 6 to 18 months. Herein, we have studied the changes induced by the infectious sporozoites in RAS‐induced memory CD8+ T cells for conferring lengthened protection. We observed that the infectious sporozoite challenge boosted the frequency of foreign antigen–experienced memory CD8+ T cells. In those CD8+ T cells, it has reduced the Annexin‐V reactivity, raised Bcl‐2 expression, and also more cells undergo homeostatic proliferation (Ki‐67+). It has also scaled down the frequency of Nur77 and CX3CR1 high expressing cells in those memory CD8+ T‐cell populations which we further correlated with better survival signals. [ABSTRACT FROM AUTHOR]

A two-dimensional steady-state model of a catalytic plate reactor for diesel steam reforming is developed. Heat is provided indirectly to endothermic reforming sites by flue gas from a SOFC tail-gas burner. Two experimentally validated kinetic models on diesel reforming on platinum (Pt) catalyst were implemented for a comparative study; the model of Parmar et al., Fuel. 2010;89(6):1212-1220 for a Pt/Al2O3 and the model of Shi et al., International Journal of Hydrogen Energy. 2009;34(18):7666-7675 for a Pt/Gd-CeO2 (GDC). The kinetic models were compared for: species concentration, approach to equilibrium, gas hourly space velocity and effectiveness factor. Cocurrent flow arrangement between the reforming and the flue gas channels showed better heat transfer compared to counter-current flow arrangement. The comparison between the two kinetic models showed that different supports play significant role in the final design of a reactor. The study also determined that initial 20% of the plate reactor has high diffusion limitation suggesting to use graded catalyst to optimize the plate reactor performance. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1102-1113, 2017 [ABSTRACT FROM AUTHOR]

Summary: Immunization with radiation‐attenuated Plasmodium sporozoites (RAS) induces sterile and long‐lasting protective immunity. Although intravenous (IV) route of RAS immunization is reported to induce superior immunity compared to intradermal (ID) injection, its role in the maintenance of sterile immunity is yet to be understood. We investigated whether the route of homologous sporozoite challenge of Plasmodium berghei (Pb) RAS‐immunized mice would influence the longevity of protection. C57BL/6 mice immunized with Pb‐RAS by IV were 100% protected upon primary IV/ID sporozoite challenge. In contrast, ID immunization resulted in 80% protection, regardless of primary challenge route. Interestingly, the route of primary challenge was found to bring difference in the maintenance of sterile protection. While IV Pb RAS‐immunized mice remained protected at all challenges regardless of the route of primary challenge, ID Pb‐RAS‐immunized mice receiving ID primary challenge became parasitaemic upon secondary IV challenge. Significantly, primary IV challenge of Pb RAS ID‐immunized mice resulted in 80% and 50% survival at secondary and tertiary challenges, respectively. According to phenotypically diverse liver CD8+ T cells, the percentages and the numbers of both CD8+ T effector memory and resident memory cells were significantly higher in IV than in ID Pb RAS‐immunized mice. IFN‐γ‐producing CD8+ T cells specific to Pb TRAP130 and MIP‐4‐Kb‐17 were also found significantly higher in IV mice than in ID mice. The enhanced T‐cell generation and the longevity of protection appear to be dependent on the parasite load during challenge when infection is tolerated under suboptimal CD8+ T‐cell response. [ABSTRACT FROM AUTHOR]

Radiation attenuated sporozoite (RAS), a whole-parasite vaccine approach, provides sterile protection against malaria. However, RAS immunization does not confer protection for long, and that has been correlated with the waning parasite-induced memory CD8 + T-cell responses. Interestingly, an intermittent infectious (wild type) sporozoite challenge to the RAS-vaccinated mice lengthened the protection period from 6 to 18 months. Herein, we have studied the changes induced by the infectious sporozoites in RAS-induced memory CD8 + T cells for conferring lengthened protection. We observed that the infectious sporozoite challenge boosted the frequency of foreign antigen-experienced memory CD8 + T cells. In those CD8 + T cells, it has reduced the Annexin-V reactivity, raised Bcl-2 expression, and also more cells undergo homeostatic proliferation (Ki-67 + ). It has also scaled down the frequency of Nur77 and CX3CR1 high expressing cells in those memory CD8 + T-cell populations which we further correlated with better survival signals., (© 2021 The Societies and John Wiley & Sons Australia, Ltd.)