Building on previous work ( 8154-8166) under neutral conditions, we examined the co-oligomerization of CHO and pyrrole to form porphryinogen under acidic conditions using density functional theory (B3LYP//6-311G**). Thermodynamically, we found that azafulvene intermediates were significantly stabilized under highly acidic conditions. Kinetically, energy barriers were lowered for C-C bond formation, discriminating in favor of reactions that lead to porphyrinogen. However, it was challenging to satisfactorily combine our thermodynamic and kinetic profiles into a unified free-energy profile because of difficulties in optimizing transition states of cationic species involving proton hops. Instead, we used neutral carboxylic acids as a proxy to study how energy barriers changed. By combining data from both neutral and acidic conditions, we estimate a free-energy profile for the initial steps of oligomerization under milder acidic conditions more relevant to prebiotic chemistry.
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http://dx.doi.org/10.1021/acsomega.9b03931 | DOI Listing |
Sci Rep
January 2025
Department of Clinical Physiology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego 13, 10-719, Olsztyn, Poland.
Studies conducted so far have shown that nano- and microplastic may disturb the intestinal microenvironment by interacting with the intestinal epithelium and the gut microbiota. Depending on the research model used, the effect on the microbiome is different-an increase or decrease in selected taxa resulting in the development of dysbiosis. Dysbiosis may be associated with intestinal inflammation, development of mental disorders or diabetes.
View Article and Find Full Text PDFCell Mol Life Sci
January 2025
Institute of Medicine, Chung Shan Medical University, No. 110, Sec. 1, Jianguo N. Rd, Taichung City, 402, Taiwan.
Background: Diabetes is a primary contributor to diabetic cardiomyopathy (DbCM), which is marked by metabolic imbalances such as elevated blood glucose and lipid levels, leading to significant structural and functional alterations in the myocardium. Elevated free fatty acids (FFAs) and hyperglycemia play critical roles in DbCM development, with FFAs inducing insulin resistance in cardiomyocytes and promoting lipid accumulation, resulting in oxidative stress and fibrosis. Current research suggests that glucagon-like peptide-1 (GLP-1) receptor agonists may effectively mitigate DbCM, although an effective treatment for this condition remains elusive, and the precise mechanisms of this protective effect are not fully understood.
View Article and Find Full Text PDFJ Appl Microbiol
January 2025
State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
Aims: The sand-fixing desert shrub Artemisia sphaerocephala produces a large amount of seed mucilage, which plays crucial roles in the adaptation of this species to desert environments. Seed mucilage has been shown to be degraded by Phanerochaete chrysosporium from habitat soils, but the process and products of this degradation remain unclear. To fill this gap, we explored the factors and processes involved in mucilage degradation.
View Article and Find Full Text PDFFEMS Microbiol Ecol
January 2025
National Food Institute, Technical University of Denmark, Kemitorvet, 2800 Kongens Lyngby, Denmark.
Oral antibiotic treatment is well known to be one of the main factors affecting gut microbiota composition by altering bacterial diversity. It decreases the abundance of butyrate-producing bacteria such as Lachnospiraceae and Ruminococcaceae, while increasing abundance of Enterobacteriaceae. The recovery time of commensal bacteria post-antibiotic treatment varies among individuals, and often, complete recovery is not achieved.
View Article and Find Full Text PDFBMJ Open
January 2025
Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK
Introduction: Persistent throat symptoms (PTS) are indicators for over 60 000 new patient referrals to NHS secondary care annually. PTS have been attributed to manifestation of gastro-oesophageal reflux disease (GORD) with the hypothesis that gastric refluxate damages and irritates the mucosa of the upper aerodigestive tract. Symptoms of PTS and GORD are commonly treated with proton pump inhibitors (PPIs) or alginates are often, incorrectly, advocated.
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