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Heat-labile enterotoxin (LT) from enterotoxigenic Escherichia coil is a heterohexameric protein consisting of an enzymatically active A subunit, LTA, and a carrier pentameric B subunit, LTB. It is clear from the crystal structure of LTB that the N-terminal [alpha]1 helix lies outside the core structure. However, the function of the N-terminal [alpha]1 helix of LTB is unknown. The present work was carried out to investigate the effect of site-directed mutagenesis of the [alpha]1 helix on LTB synthesis. Six amino acids (PQSITE) located at positions 2-7 from the N terminus, including 4 aa from the [alpha]1 helix, were deleted by site-directed mutagenesis. The deletion resulted in complete inhibition of LTB expression in E. coil when expressed along with its signal sequence. A single amino acid deletion within the [alpha]1 helix also resulted in loss of expression. However, a single amino acid deletion outside the [alpha]1 helix did not affect LTB synthesis. Mutant proteins, whose synthesis was not detected in vivo, could be successfully translated in vitro by using the coupled transcription--translation system. Immunoblot analysis, Northern blot analysis, and in vitro transcription-translation data collectively indicate that the lack of synthesis of the mutant proteins is caused by the immediate degradation of the expressed product by cellular proteases rather than by faulty translation of mutant LTB mRNA. Coexpression of the LTA could not rescue the degradation of LTB mutants. gene expression | site-directed mutagenesis | coupled transcription-translation

Background: With the ever-increasing demand on acute healthcare, the hospital discharge process and delayed discharges are considered relevant in achieving optimal performance in clinical settings. The purpose of this paper is to review the literature to identify conceptual and operational definitions of delayed discharges, identify causes and effects of delayed discharges, and also to explore the literature for interventions aimed at decreasing the impact (in terms of reducing the number/rate of delays) of delayed discharges in acute healthcare settings. Methods: An extensive literature search yielded a total of 26 248 records. Sixty-four research articles were included in the scoping review after considering inclusion/exclusion criteria and the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) search strategy. The following databases were utilized: Cochrane, EBSCO, PubMed, PubMed Central, Medline, and Web of Science. The search was carried out between January 2017 and March 2020 and covered literature ranging from 1990 to 2019. Results were reviewed by authors for duplicates and filtered using the inclusion/ exclusion criteria. Tables were created to classify the chosen articles (n = 64), allowing us to organise findings and results. Results: Conceptual and operational definitions were analysed. In turn, causes and effects of delayed discharges were extracted and represented in diagrammatic format, together with specific interventions used in acute healthcare settings to lessen the effect of delayed discharges. Operational definitions of delayed discharges were found to be more difficult to establish, particularly in the light of the vast number of different scenarios and workplace interventions uncovered in the literature. The main causes of delayed discharges were faulty organisational management, inadequate discharge planning, transfer of care problems, and age. The main effects were bed-blocking, A&E (Accident & Emergency) overcrowding, and financial implications. The main interventions included 'discharge before noon' initiative, 'discharge facilitation tools,' 'discharge delay tracking' mechanisms, and the role of general practitioners and social care staff. Conclusion: This paper fills a gap in the fragmented literature on delayed inpatient discharges by providing a researchbased perspective on conceptual and operational definitions, causes and effects, as well as interventions to minimize their impact. The findings and definitions are intended as points of reference for future research. [ABSTRACT FROM AUTHOR]

Byline: Lalit. Garg, Sanjay. Chhabra, Gopal. Singla, Sunil. Lakhwani Sir, Compartment Syndrome is a life-threatening condition in which rapidly increasing interstitial pressures in a limb compartment compromise the vascular supply [...]