Antiproliferative effect of natural and semisynthetic polyethers from .

Squalene-derived polyethers are a unique class of compounds that display a great diversity of structures and a broad array of bioactivities, among which its notable antiproliferative activity stands out against various types of cancer cell lines. In this study, eighteen triterpene squalene-derived polyethers, including twelve natural products and six synthetic derivatives, obtained from the red alga Gil-Rodríguez & Haroun were screened for their antiproliferative activity against six cancer cell lines: A549, HBL-100, HeLa, SW1573, T-47D, and WiDr; and a structure-activity relationship (SAR) study was established.

Improvement in intubation success during COVID-19 pandemic with a simple and low-cost intervention: A quasi-experimental study.

Objectives: primary objective: to improve the FPS rates after an educational intervention.

Secondary Objective: to describe variables related to FPS in an ED and determine which ones were related to the highest number of attempts.

Design: it was a prospective quasi-experimental study.

[Glucocorticoids in leptospira alveolar hemorrhage].

We present the clinical cases of two patients who were admitted to the HIGA San Martín de La Plata emergency ward with a clinical picture compatible with leptospirosis, who evolved with respiratory failure and alveolar hemorrhage. In both, glucocorticoids were administered with good evolution. A bibliographic search of articles published since 2005 in Spanish and English and a review of the topic was carried out.

Structure and Computational Basis for Backbone Rearrangement in Marine Oxasqualenoids.

Six novel oxasqualenoids (polyether triterpenes) were isolated from the red alga . Laurokanols A-E (-) comprise an unreported tricyclic core with a [6,6]-spiroketal system. Yucatecone () shows a biogenetically intriguing epimerization at C14.

Oxasqualenoids from Laurencia viridis: Combined Spectroscopic-Computational Analysis and Antifouling Potential.

The chemical study of the red alga Laurencia viridis has led to the isolation of four new polyether triterpenoids: 28-hydroxysaiyacenol B (2), saiyacenol C (3), 15,16-epoxythyrsiferol A (4), and 15,16-epoxythyrsiferol B (5). The structures of 2 and 3 were established mainly by NMR data analysis and comparison with the well-known metabolite dehydrothyrsiferol (1). However, due to the existence of a nonprotonated carbon within the epoxide functionality, stereochemical assignments in 4 and 5 required an in-depth structural study that included NOESY data, J-based configuration analysis, comparison with synthetic models, and DFT calculations.

Stereochemistry of complex marine natural products by quantum mechanical calculations of NMR chemical shifts: solvent and conformational effects on okadaic acid.

Marine organisms are an increasingly important source of novel metabolites, some of which have already inspired or become new drugs. In addition, many of these molecules show a high degree of novelty from a structural and/or pharmacological point of view. Structure determination is generally achieved by the use of a variety of spectroscopic methods, among which NMR (nuclear magnetic resonance) plays a major role and determination of the stereochemical relationships within every new molecule is generally the most challenging part in structural determination.

Inflammatory responses in the intestinal mucosa of gerbils and hamsters experimentally infected with the adult stage of Taenia solium.

The inflammatory response in gerbils and hamsters harbouring experimental infections with Taenia solium adult parasites as well as worm burden and duration of infections were examined. For this purpose, non-suppressed or immunosuppressed rodents were infected with eight cysticerci and necropsied at different times up to 35 days post-infection. Cells in the mucosa surrounding the implantation site of T.