The intestinal epithelium functions to effectively restrict the causal uptake of luminal contents but has been demonstrated to transiently increase paracellular permeability properties to provide an additional entry route for dietary macromolecules. We have examined a method to emulate this endogenous mechanism as a means of enhancing the oral uptake of insulin. Two sets of stable Permeant Inhibitor of Phosphatase (PIP) peptides were rationally designed to stimulate phosphorylation of intracellular epithelial myosin light chain (MLC) and screened using Caco-2 monolayers in vitro. Apical application of PIP peptide 640, designed to disrupt protein–protein interactions between protein phosphatase 1 (PP1) and its regulator CPI-17, resulted in a reversible and non-toxic transient reduction in Caco-2 monolayer trans-epithelial electric resistance (TEER) and opening of the paracellular route to 4 kDa fluorescent dextran but not 70 kDa dextran in vitro. Apical application of PIP peptide 250, designed to impede MYPT1-mediated regulation of PP1, also decreased TEER in a reversible and non-toxic manner but transiently opened the paracellular route to both 4 and 70 kDa fluorescent dextrans. Direct injection of PIP peptides 640 or 250 with human insulin into the lumen of rat jejunum caused a decrease in blood glucose levels that was PIP peptide and insulin dose-dependent and correlated with increased pMLC levels. Systemic levels of insulin suggested approximately 3–4% of the dose injected into the intestinal lumen was absorbed, relative to a subcutaneous injection. Measurement of insulin levels in the portal vein showed a time window of absorption that was consistent with systemic concentration-time profiles and approximately 50% first-pass clearance by the liver. Monitoring the uptake of a fluorescent form of insulin suggested its uptake occurred via the paracellular route. Together, these studies add validation to the presence of an endogenous mechanism used by the intestinal epithelium to dynamically regulate its paracellular permeability properties and better define the potential to enhance the oral delivery of biopharmaceuticals via a transient regulation of an endogenous mechanism controlling the intestinal paracellular barrier.

Salmonella enterica is a common cause of many enteric infections worldwide and is successfully engineered to deliver heterologous antigens to be used as vaccines. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) RNA-guided Cas9 endonuclease is a promising genome editing tool. In the current study, a CRISPR-Cas9 system was used to target S.enterica sdiA that encodes signal molecule receptor SdiA and responds to the quorum sensing (QS) signaling compounds N-acylhomoserine lactones (AHLs). For this purpose, sdiA was targeted in both S.enterica wild type (WT) and the ΔssaV mutant strain, where SsaV has been reported to be an essential component of SPI2-T3SS. The impact of sdiA mutation on S. enterica virulence was evaluated at both early invasion and later intracellular replication in both the presence and absence of AHL. Additionally, the influence of sdiA mutation on the pathogenesis S. enterica WT and mutants was investigated in vivo, using mice infection model. Finally, the minimum inhibitory concentrations (MICs) of various antibiotics against S. enterica strains were determined. Present findings show that mutation in sdiA significantly affects S.enterica biofilm formation, cell adhesion and invasion. However, sdiA mutation did not affect bacterial intracellular survival. Moreover, in vivo bacterial pathogenesis was markedly lowered in S.enterica ΔsdiA in comparison with the wild-type strain. Significantly, double-mutant sdiA and ssaV attenuated the S. enterica virulence and in vivo pathogenesis. Moreover, mutations in selected genes increased Salmonella susceptibility to tested antibiotics, as revealed by determining the MICs and MBICs of these antibiotics. Altogether, current results clearly highlight the importance of the CRISPR-Cas9 system as a bacterial genome editing tool and the valuable role of SdiA in S.enterica virulence. The present findings extend the understanding of virulence regulation and host pathogenesis of Salmonellaenterica.

Background Over the last two decades, humanity has observed the extraordinary anomaly caused by novel, weird coronavirus strains, such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). As the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus has made its entry into the world, it has dramatically affected life in every domain by continuously producing new variants. The vaccine development is an ongoing process, although some vaccines got marketed. The big challenge is now whether the vaccine candidates can provide long-lasting protection or prevention against mutant variants. Methods The information was gathered from various journals, electronic searches via Internet-based information such as PubMed, Google Scholar, Science Direct, online electronic journals, WHO landscape, world meters, WHO website, and News. Results This review will present and discuss some coronavirus disease 19 (COVID-19) related aspects including: the pathophysiology, epidemiology, mutant variants vaccine candidates, vaccine efficacy, and management strategies. Due to the high death rate, continuous spread, an inadequate workforce, lack of required therapeutics, and incomplete understanding of the viral strain, it becomes crucial to build the knowledge of its biological characteristics and make available the rapid diagnostic and vital therapeutic machinery for the combat and management of an infection. Conclusion The data summarizes current research on the COVID 19 infection and therapeutic interventions, which will direct future decision-making on the effort-worthy phases of the COVID 19 and the development of critical therapeutics. The only possible solution is the vaccine development targeting against all variant strains to halt its progress; the identified theoretical and practical knowledge can eliminate the gaps to improve a better understanding of the novel coronavirus structure and its design of a vaccine. In addition, to that the long-lasting protection is another challenging objective that need to be looked into.

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One of the recent advancements in research is the application of natural products in developing newly effective formulations that have few drawbacks and that boost therapeutic effects. The goal of the current exploration is to investigate the effect of jojoba oil in augmenting the anti-inflammatory effect of Brucine natural alkaloid. This is first development of a formulation that applies Brucine and jojoba oil int a PEGylated liposomal emulgel proposed for topical application. Initially, various PEGylated Brucine liposomal formulations were fabricated using a thin-film hydration method. (22) Factorial design was assembled using two factors (egg Phosphatidylcholine and cholesterol concentrations) and three responses (particle size, encapsulation efficiency and in vitro release). The optimized formula was incorporated within jojoba oil emulgel. The PEGylated liposomal emulgel was inspected for its characteristics, in vitro, ex vivo and anti-inflammatory behaviors. Liposomal emulgel showed a pH of 6.63, a spreadability of 48.8 mm and a viscosity of 9310 cP. As much as 40.57% of Brucine was released after 6 h, and drug permeability exhibited a flux of 0.47 µg/cm2·h. Lastly, % of inflammation was lowered to 47.7, which was significant effect compared to other formulations. In conclusion, the anti-inflammatory influence of jojoba oil and Brucine was confirmed, supporting their integration into liposomal emulgel as a potential nanocarrier.