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Strain analysis offers a valuable tool to assess myocardial mechanics, allowing for the detection of impairments in heart function. This study aims to evaluate the pattern of myocardial strain in patients with heart failure (HF).

New tetramic acid derivatives, (±)-conipyridoins A–D (1–4), conipyridoins E (5) and F (6), and new 4-hydroxy-2-pyridone alkaloids (±)-didymellamide E (7), (+)-didymellamide B (8), (+)-N-hydroxyapiosporamide (9), and didymellamides F–H (10–12) were isolated and identified from the solid culture of the fungus Coniochaeta cephalothecoides. Chiral resolution of 1, 2, 3, 4, and 7gave five pairs of enantiomers: 1a/1b, 2a/2b, 3a/3b, 4a/4b, and 7a/7b, respectively. Stereochemistry of 1aand 1b, and 2aand 2bwas established and confirmed by the single-crystal X-ray diffraction and electronic circular dichroism (ECD) methods. Absolute configuration in 3a, 3b, 4a, 4b, 7a,and 7bwas assigned by ECD calculations. Compounds 1–6possess an unprecedented chemical skeleton featuring a decalin ring and a tetramic acid moiety. Compound 11significantly inhibited the growth of Candida albicansand Aspergillus fumigatuswith minimum inhibitory concentration (MIC) of 3.13 and 1.56 μM, respectively, and was further confirmed to be a new chitin synthesis inhibitor. Compound 5exhibited the strongest activity against the growth of both Staphylococcus aureusand MRSA with MIC value of 0.97 μM. In the light of a co-occurrence of 3-acyl tetramic acids and biogenetically related pyridine alkaloids, the biosynthetic pathway for 1–12was postulated.

The solventogenic bacterium Clostridium acetobutylicumis an important species of the Clostridiumcommunity. To develop a fundamental tool that is useful for biological studies of C. acetobutylicum, we established a high resolution proteome reference map for this species. We identified 1206 spots representing 564 different proteins by mass spectrometry, covering approximately 50% of major metabolic pathways. To better understand the relationship between butanol tolerance and butanol yield, we performed a comparative proteomic analysis between the wild type strain DSM 1731 and the mutant Rh8, which has higher butanol tolerance and higher butanol yield. Comparative proteomic analysis of two strains at acidogenic and solventogenic phases revealed 102 differentially expressed proteins that are mainly involved in protein folding, solvent formation, amino acid metabolism, protein synthesis, nucleotide metabolism, transport, and others. Hierarchical clustering analysis revealed that over 70% of the 102 differentially expressed proteins in mutant Rh8 were either upregulated (e.g., chaperones and solvent formation related) or downregulated (e.g., amino acid metabolism and protein synthesis related) in both acidogenic and solventogenic phase, which, respectively, are only upregulated or downregulated in solventogenic phase in the wild type strain. This suggests that Rh8 cells have evolved a mechanism to prepare themselves for butanol challenge before butanol is produced, leading to an increased butanol yield. This is the first report on the comparative proteome analysis of a mutant strain and a base strain of C. acetobutylicum. The fundamental proteomic data and analyses will be useful for further elucidating the biological mechanism of butanol tolerance and/or enhanced butanol production.