Relationship between enteral nutrition timing and 28-day mortality in critically ill stroke patients in the MIMIC-IV database.

Background: The ideal timing for commencing enteral nutrition (EN) in critically ill stroke patients in the intensive care unit (ICU) remains a subject of debate, with ongoing controversy regarding the impact of early EN (EEN) initiation. In this study, we investigated the association between the timing of EN initiation and 28-day mortality using data from the MIMIC-IV database. Methods: This study employed a retrospective cohort design using the MIMIC-IV database to identify stroke patients who received EN during their hospital stay. The main focus of this investigation was to examine 28-day mortality among these patients following hospital admission. Various demographic, clinical, laboratory, and intervention variables were considered as covariates. The Cox regression analysis was employed to assess the correlation between the timing of EN initiation and 28-day mortality, and restricted cubic splines (RCS) analysis was used to test for non-linear correlation. Patients were then stratified into two cohorts depending on the timing of EN initiation: within 2 days (n = 564) and beyond 2 days (n = 433). A multivariate Cox regression analysis was used to investigate the difference in 28-day mortality between the groups. Results: A total of 997 participants were included in this study, with 318 (31.9%) dying within 28 days. We observed that the timing of EN initiation correlated with 28-day mortality, but this correlation was not significant after adjusting for covariates (crude HR: 0.94, 95% CI: 0.88-1, p = 0.044; adjusted HR: 0.96, 95% CI: 0.9-1.02, p = 0.178). The RCS analysis showed that the correlation was not non-linear. Notably, in the multivariate regression models, early EN initiation was associated with a higher mortality rate compared to late EN initiation [odds ratio (OR) = 1.34, 95% CI: 1.06-1.67, p = 0.012]. After adjusting for various confounding factors in the multivariate Cox regression models, we identified that patients in the early EN group had a 28% higher risk of mortality than those in the reference group (OR = 1.27, 95% CI: 1-1.61, p = 0.048). These associations remained consistent across various patient characteristics, as revealed through stratified analyses. Conclusions: Early commencement of EN in critically ill stroke patients may be linked to a higher risk of 28-day mortality, highlighting the need for further investigation and a more nuanced consideration of the optimal timing for commencing EN in this patient population.

Non-classical C-saccharide linkage of dehydroalanine: synthesis of C-glycoamino acids and C-glycopeptides.

Herein, a non-classical C-saccharide linkage is reported via a C5 radical of pentose or C6 radical of hexose addition to Michael acceptors. C(sp3)-S cleaved glycosyl thianthrenium salts are developed as the glycosyl radical agents. The reaction provides an efficient toolkit to synthesize ß-glycosyl substituted unnatural amino acids as well as for the late-stage C-saccharide modification of peptides.

Visible-light-mediated catalyst-free synthesis of unnatural α-amino acids and peptide macrocycles.

The visible light induced, photocatalysts or photoabsorbing EDA complexes mediated cleavage of pyridinium C-N bond were reported in the past years. Here, we report an ionic compound promote homolytic cleavage of pyridinium C-N bond by exploiting the photonic energy from visible light. This finding is successfully applied in deaminative hydroalkylation of a series of alkenes including naturally occurring dehydroalanine, which provides an efficient way to prepare ß-alkyl substituted unnatural amino acids under mild and photocatalyst-free conditions. Importantly, by using this protocol, the deaminative cyclization of peptide backbone N-terminals is realized. Furthermore, the use of Et3N or PPh3 as reductants and H2O as hydrogen atom source is a practical advantage. We anticipate that our protocol will be useful in peptide synthesis and modern peptide drug discovery.

Strong cellulose hydrogel as underwater superoleophobic coating for efficient oil/water separation.

Cellulose hydrogels with high compressive strength were constructed by physical dissolution/regeneration process. Cellulose was dissolved in lithium hydroxide/urea aqueous solvent and lithium tetrafluoroborate aqueous solution was used for regeneration, to obtain hydrogels with compact structure. Compressive strength of the hydrogel reached 14.5 MPa, higher than cellulose based hydrogels of same kind in literature. The cellulose hydrogel was further used as coatings on stainless mesh, to separate oil/water mixtures by gravity. The hydrogel covered uniformly the mesh, and demonstrated underwater superoleophobicity. The coated mesh exhibited separation efficiency over 98.90 %, high permeate flux up to 38064 L m-2 h-1 and excellent reusability, when separating mixtures of water and various oil. Furthermore, the coated mesh remained underwater superhydrophobic in salty condition (contact angel of 154.2 ±â€¯2.2°). The facile approach to fabricate cellulose hydrogel coated mesh demonstrated great potential in water treatment, as well as sustainability in utilizing biomass resources.