Dengue determinants: Necessities and challenges for universal dengue vaccine development.

Dengue illness can range from mild illness to life-threatening haemorrhage. It is an Aedes-borne infectious disease caused by the dengue virus, which has four serotypes. Each serotype acts as an independent infectious agent. The antibodies against one serotype confer homotypic immunity but temporary protection against heterotypic infection. Dengue has become a growing health concern for up to one third of the world's population. Currently, there is no potent anti-dengue medicine, and treatment for severe dengue relies on intravenous fluid management and pain medications. The burden of dengue dramatically increases despite advances in vector control measures. These factors underscore the need for a vaccine. Various dengue vaccine strategies have been demonstrated, that is, live attenuated vaccine, inactivated vaccine, DNA vaccine, subunit vaccine, and viral-vector vaccines, some of which are at the stage of clinical testing. Unfortunately, the forefront candidate vaccine is less than satisfactory, and its performance depends on serostatus and age factors. The lessons from clinical studies depicted ambiguity concerning the efficacy of dengue vaccine. Our study highlighted that viral structural heterogeneity, epitope accessibility, autoimmune complications, genetic variants, genetic diversities, antigen competition, virulence variation, host-pathogen specific interaction, antibody-dependent enhancement, cross-reactive immunity among Flaviviruses, and host-susceptibility determinants not only influence infection outcomes but also hampered successful vaccine development. This review integrates dengue determinants allocated necessities and challenges, which would provide insight for universal dengue vaccine development.

Designing dibenzosilole core based, A2-π-A1-π-D-π-A1-π-A2 type donor molecules for promising photovoltaic parameters in organic photovoltaic cells.

In this research work, four new molecules from the π-A-π-D-π-A-π type reference molecule "DBS-2PP", were designed for their potential application in organic solar cells by adding peripheral A2 acceptors to the reference. Under density functional theory, a comprehensive theoretical investigation was conducted to examine the structural geometries, along with the optical and photovoltaic parameters; comprising frontier molecular orbitals, density of states, light-harvesting effectiveness, excitation, binding, and reorganizational energies, molar absorption coefficient, dipole moment, as well as transition density matrix of all the molecules under study. In addition, some photo-voltaic characteristics (open circuit photo-voltage and fill factor) were also studied for these molecules. Although all the developed compounds (D1-D4) surpassed the reference molecule in the attributes mentioned above, D4 proved to be the best. D4 possessed the narrowest band-gap, as well as the highest absorption maxima and dipole moment of all the molecules in both the evaluated phases. Moreover, with PC61BM as the acceptor, D4 showed the maximum V OC and FF values. Furthermore, while D3 had the greatest hole mobility owing to its lowest value of hole reorganization energy, D4 exhibited the maximum electron mobility due to its lowermost value of electron reorganization energy. Overall, all the chromophores proposed in this study showed outstanding structural, optical, and photovoltaic features. Considering this, organic solar cell fabrication can be improved by using these newly derived donors at the donor-acceptor interfaces.