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Background: Streptococcus mutans (S. mutans) contributes to caries. The biofilm formed by S. mutans exhibits greater resistance to drugs and host immune defenses than the planktonic form of the bacteria. The objective of this study was to evaluate the anti-biofilm effect of cordycepin from the perspective of metabolomics. Methods: The minimum inhibitory concentration (MIC) was determined to evaluate the antimicrobial effect of cordycepin on planktonic S. mutans. The 24-h biofilm was treated with 128 µg/mL of cordycepin for 10 min at the 8- or 20-h time points. Biofilm biomass and metabolism were assessed using crystal violet and MTT assays and cordycepin cytotoxicity was evaluated in human oral keratinocytes (HOK) using CCK-8 assays. The live bacterial rate and the biofilm volume were assessed by confocal laser scanning microscopy. Metabolic changes in the biofilm collected at different times during with cordycepin were analyzed by metabolomics and verified by quantitative real-time PCR. Results: The results showed that treatment with 128 µg/mL cordycepin reduced both the biomass and metabolic activity of the biofilm without killing the bacteria, and cordycepin at this concentration showed good biocompatibility. Metabolomics analysis showed that differentially abundant metabolites following cordycepin treatment were mainly related to purine and nucleotide metabolism. After immediate treatment with cordycepin, genes related to purine and nucleotide metabolism were downregulated, and the levels of various metabolites changed significantly. However, the effect was reversible. After continuing culture for 4 h, the changes in genes and most metabolites were reversed, although the levels of 2'-deoxyadenosine, 2'-deoxyinosine, and adenine remained significantly different. Conclusions: Cordycepin has the effect of anti-biofilm of S. mutans, mainly related to purine and nucleotide metabolism. [ABSTRACT FROM AUTHOR]

Although sarcopenia has been a serious public health concern worldwide in recent years, its effective prevention and intervention measures are still lacking. The latest research has found that autophagy dysfunction is an essential mechanism in the pathogenesis of sarcopenia. And meanwhile, increasing studies have shown that phytonutrients consumption is positively correlated with the maintenance of skeletal muscle mass and strength, which involves the regulation of the autophagy pathway. However, due to the opposite environmental-dependent effect of autophagy in sarcopenia, targeting autophagy by phytonutrients as the treatment of sarcopenia is sometimes considered controversial. Thus, in this review, based on the illustration of the relationship between autophagy and skeletal muscle and the complex changes of autophagy in sarcopenia, the phytonutrients ameliorating sarcopenia by regulating autophagy are reviewed with emphasis, and the possible underlying mechanisms are systematically summarized. Despite some controversies, most current studies support the idea that maintaining basal and functional autophagy contributes to the treatment of sarcopenia. Several phytonutrients exhibit substantial beneficial effects on sarcopenia by targeting autophagy, with polyphenols (especially catechins and urolithin A) considered to be of potentially effective clinical relevance. Hence, the development of phytonutrients is a promising approach to the treatment of sarcopenia and its complications. [ABSTRACT FROM AUTHOR]

Surface processes of CO2 reduction on Pt(210), Pt(310), and Pt(510) electrodes were studied by cyclic voltammetry. Different surface structures of these platinum single crystal electrodes were obtained by various treatment conditions. The experimental results illustrated that the electrocatalytic activity of Pt single crystal electrodes towards CO2 reduction is decreased in an order of Pt(210)>Pt(310)>Pt(510), i.e., with the decrease of (110) step density on well-defined surfaces. When the surfaces were reconstructed due to oxygen adsorption, the catalytic activity of all the three electrodes has been enhanced to a certain extent. Although the activity order remains unchanged, the electrocatalytic activity has been enhanced more significantly as the density of (110) step sites is more intensive on the Pt single crystal surface. It has revealed that the more open the surface structure is, the more active the Pt single crystal electrode will be, and the easier for the electrode to be transformed into a surface structure that exhibits higher activity under external inductions. However, the relatively ordered surfaces of Pt single crystal electrode are comparatively stable under the same external inductions. The present study has gained knowledge on the interaction between CO2 and Pt single crystal electrode surfaces at a microscopic level, and thrown new insight into understanding the surface processes of electrocatalytic reduction of CO2. [ABSTRACT FROM AUTHOR]

Title compounds are prepared from 1,4-diaryl-1,3-butadiynes (I) by reaction with H2O, primary amines (III) or Na2S, respectively. [ABSTRACT FROM AUTHOR]

Mitochondrial dysfunction increasingly becomes a target for promoting healthy aging and longevity. The dysfunction of mitochondria with age ultimately leads to a decline in physical functions. Among them, biogenesis dysfunction and the imbalances in the metabolism of reactive oxygen species and mitochondria as signaling organelles in the aging process have aroused our attention. Dietary intervention in mitochondrial dysfunction and physical decline during aging processes is essential, and greater attention should be directed toward healthful legume intake. Legumes are constantly under investigation for their nutritional and bioactive properties, and their consumption may yield antiaging and mitochondria-protecting benefits. This review summarizes mitochondrial dysfunction with age, discusses the benefits of legumes on mitochondrial function, and introduces the potential role of legumes in managing aging-related physical decline. Additionally, it reveals the benefits of legume intake for the elderly and offers a viable approach to developing legume-based functional food., (© 2024 Institute of Food Technologists®.)

Streptococcus mutans ( S. mutans ) is one of the primary pathogens responsible for dental caries. Streptococcus gordonii ( S. gordonii ) is one of the early colonizers of dental plaque and can compete with S. mutans for growth. In the present analysis, we explored key target genes against S. gordonii in S. mutans using 80 S. mutans clinical isolates with varying capabilities against S. gordonii . A principal coordinate analysis revealed significant genetic diversity differences between antagonistic and non-antagonistic groups. Genomic comparisons revealed 33 and 61 genes that were, respectively, positively and negatively correlated with S. mutans against S. gordonii , with RNA-sequencing (RNA-seq) highlighting 11 and 43 genes that were, respectively, upregulated and downregulated in the antagonistic group. Through a combination of these results and antiSMASH analysis, we selected 16 genes for qRT-PCR validation in which the expression levels of SMU_137 (malate dehydrogenase, mleS), SMU_138 (malate permease, mleP), SMU_139 (oxalate decarboxylase, oxdC), and SMU_140 (glutathione reductase) were consistent with RNA-seq results. SMU_1315c-1317c (SMU_1315c transport-related gene) and SMU_1908c-1909c were, respectively, downregulated and upregulated in the antagonistic group. The expression patterns of adjacent genes were closely related, with correlation coefficient values greater than 0.9. These data reveal new targets (SMU_137-140, SMU_1315c-1317c, and SMU_1908c-1909c) for investigating the critical gene clusters against S. gordonii in S. mutans clinical isolates., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liu, Sun, Liu, Hu, Xu, Zheng, Wang, Zeng and Zhang.)

Introduction. Streptococcus mutans is an important cariogenic microbe. Hypothesis/Gap Statement. The potential characteristics of S. mutans isolates from site-specific dental plaque are still not clear. Aim. This study aimed to investigate the phenotypic and genetic characteristics of S. mutans isolates from site-specific dental plaque in China. Methodology. We used S. mutans isolated from children with early-childhood caries (ECC) and caries-free children to compare the phenotypic and genetic characteristics of S. mutans from site-specific dental plaque samples. The ECC subjects presented two sites: a cavitated lesion and a sound surface. The caries-free subjects presented one sound surface. Growth pattern, biofilm, decrease in pH, extracellular polysaccharide, expression levels of virulence-related genes, multilocus sequence typing (MLST) and phylogenetic trees were evaluated among these three sites. Results. The phenotypes detected between the cavitated and sound surfaces of ECC children were similar. However, the capacity for biofilm formation, pH drop and expression levels of genes ( gtfB and spaP ) of S. mutans in the caries-free group were lower compared with those of the ECC group. We identified 44 new alleles and 77 new sequence types. More than 90 % of the children with ECC shared an identical sequence type. The distribution of sequence types among different subjects showed diversity, and child-to-child transmission was detected. Conclusions. This is the first report of MLST on site-specific dental plaques in a single subject, and indicates that S. mutans isolated from site-specific dental plaque of a single subject showed similar phenotypes as a result of the isolates were closely related.

Matrix metalloproteinase 14 (MMP14) has been shown to play a significant role in several types of cancers, but little is known about the function of MMP14 in nasopharyngeal carcinoma (NPC) carcinogenesis. The aim of this study was to investigate the role of MMP14 in NPC using NPC tumor samples or tissue microarray. We have shown that MMP14 was increased in NPC samples compared with normal nasopharynx (NP) tissues in microarray data (GSE13597). Both MMP14 mRNA and protein expression were markedly higher in NPC tissues than in NP tissues. High levels of MMP14 protein were found positively correlate with the status of late clinical stages of tumor and tumor with lymph node metastasis. Moreover, we have shown that MMP14 expression promoted the cell migration and invasion of NPC cells in vitro and regulated the expression of EMT-associated genes. Our data demonstrated that MMP14 plays an important role in regulation of migration and invasion of NPC cells, and constitutes a potential novel therapeutic target for NPC.