The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis.

PURPOSE: Previous surveys have reported that children with vitamin D deficiency were likely to suffer from early childhood caries (ECC). The aim of this systematic review and meta-analysis was to determine 1. whether the status of vitamin D is intrinsically related to the occurrence of ECC and 2. the optimal level of vitamin D for the prevention of ECC. MATERIALS AND METHODS: The database of PubMed, Web of Science, Cochrane, Embase and Google scholar were searched for targeted literature. The eligibility criteria were observational studies in which children with ECC were compared to children without ECC in terms of their vitamin D status. Applying the Newcastle-Ottawa tool, study selection, data extraction, and risk of bias assessment were performed by 2 reviewers independently. Meta-analysis was performed using the Cochrane Collaboration's Review Manager 5.4 software. RESULTS: 501 articles were retrieved from the electronic databases; 11 studies were finally included in systematic review, 10 studies of which were submitted to meta-analysis. The 25(OH)D levels in the ECC group were statistically significantly lower compared with that in the caries-free group (WMD = -13.96, 95% CI: [-19.88,-8.03], p < 0.001), especially in regard to the association between S-ECC and vitamin D (WMD = -18.64, 95% CI: [-20.06,-17.22], p < 0.001). The subgroup analyses in terms of geographical region demonstrated that children with a level of 25(OH)D of 50-75 nmol/l were more likely to have ECC than those with over 75 nmol/l (OR = 1.42, 95% CI: [1.26,1.60], p < 0.001), with data from Asia and Europe combined for analysis Conclusions: The level of vitamin D was lower in children with ECC than in caries-free children, and the correlation between S-ECC and vitamin D was even stronger. The optimal 25(OH)D level for preventing occurrence and development of ECC was ≥ 75 nmol/l. Thus, clinicians should view the development of early caries also from a systemic perspective.

Structural properties and biological activities of the extracellular polysaccharide of Bacillus subtilis LZ13-4.

The remarkable functional characteristics of Bacillus subtilis extracellular polysaccharides (BSPS) are of great interest. Therefore, in the present study, BSPS was isolated and characterized to obtain two fractions, BSPS-1 and BSPS-2, respectively, and to investigate their biological activities. BSPS-1 contained fructose, glucose, and galactose (molar ratio: 25.27:43.37:31.36), while BSPS-2 contained fructose with only trace amounts of glucose, galactose, and mannose (molar ratio: 55.08:19.03:19.21:6.68), and their respective average molecular weights were 16.9 kDa and 202.67 kDa. With a 93.55 % clearance of ABTS•+ at a concentration of 2 mg/mL of BSPS-1, the antioxidant activity revealed that BSPS-1 had greater antioxidant activity than BSPS-2 and that both were concentration-dependent. The inhibitory effect on HepG2 cells demonstrated that BSPS-1 and BSPS-2 significantly inhibited the proliferation of HepG2 and increased the expression of apoptotic proteins, causing apoptosis. The inhibition rate on HepG2 cells was dose-dependent and reached 52.7 % and 40.3 % after 48 h of action. BSPS-2 and 800 µg/mL BSPS-1 growth was inhibited in the G1/G0 phase, while 200 and 400 µg/mL BSPS-1 growth was inhibited in the S phase. In conclusion, the study of the BSPS's structure and properties can offer a theoretical foundation for real-world industrial applications.

Antimicrobial peptides: An alternative to traditional antibiotics.

As antibiotic-resistant bacteria and genes continue to emerge, the identification of effective alternatives to traditional antibiotics has become a pressing issue. Antimicrobial peptides are favored for their safety, low residue, and low resistance properties, and their unique antimicrobial mechanisms show significant potential in combating antibiotic resistance. However, the high production cost and weak activity of antimicrobial peptides limit their application. Moreover, traditional laboratory methods for identifying and designing new antimicrobial peptides are time-consuming and labor-intensive, hindering their development. Currently, novel technologies, such as artificial intelligence (AI) are being employed to develop and design new antimicrobial peptide resources, offering new opportunities for the advancement of antimicrobial peptides. This article summarizes the basic characteristics and antimicrobial mechanisms of antimicrobial peptides, as well as their advantages and limitations, and explores the application of AI in antimicrobial peptides prediction amd design. This highlights the crucial role of AI in enhancing the efficiency of antimicrobial peptide research and provides a reference for antimicrobial drug development.

Biofilm tolerance, resistance and infections increasing threat of public health.

Microbial biofilms can cause chronic infection. In the clinical setting, the biofilm-related infections usually persist and reoccur; the main reason is the increased antibiotic resistance of biofilms. Traditional antibiotic therapy is not effective and might increase the threat of antibiotic resistance to public health. Therefore, it is urgent to study the tolerance and resistance mechanism of biofilms to antibiotics and find effective therapies for biofilm-related infections. The tolerance mechanism and host reaction of biofilm to antibiotics are reviewed, and bacterial biofilm related diseases formed by human pathogens are discussed thoroughly. The review also explored the role of biofilms in the development of bacterial resistance mechanisms and proposed therapeutic intervention strategies for biofilm related diseases.

Identification, Characterization, and Receptor Binding Mechanism of New Umami Peptides from Traditional Fermented Soybean Paste (Dajiang).

Dajiang, a traditional Chinese condiment, is made from fermented soybeans. It is highly popular among consumers as a result of its delicious umami flavor, which mainly originates from umami peptides. To examine the mechanism of umami taste in Dajiang, we selected Dajiang samples with strong umami taste and subjected them to purification and identification analysis using ethanol precipitation, gel chromatography, reversed-phase high-performance liquid chromatography, and ultraperformance liquid chromatography-tandem mass spectrometry. Subsequently, on the basis of toxicity and umami prediction analysis, we screened, synthesized, and characterized three novel bean umami peptides in Dajiang: TLGGPTTL, 758.4174 Da; GALEQILQ, 870.4811 Da; and HSISDLQ, 911.4713 Da. Their sensory threshold values were 0.25, 0.40, and 0.17 mmol/L, respectively. Furthermore, molecular docking results showed that hydrogen-bonding and hydrophobic interactions are important interaction forces in the binding of umami peptide to taste receptors. Ser147 and Glu148 of the T1R3 taste receptor are important amino acid residues for binding of the three umami peptides. This study uncovers the mechanism of umami-peptide-driven flavor in fermented soybean products.

Engineered Plant-Derived Nanovesicles Facilitate Tumor Therapy: Natural Bioactivity Plus Drug Controlled Release Platform.

Tumors are the second-most common disease in the world, killing people at an alarming rate. As issues with drug resistance, lack of targeting, and severe side effects are revealed, there is a growing demand for precision-targeted drug delivery systems. Plant-derived nanovesicles (PDNVs), which arecomposed of proteins, lipids, RNA, and metabolites, are widely distributed and readily accessible. The potential for anti-proliferative, pro-apoptotic, and drug-resistant-reversing effects on tumor cells, as well as the ability to alter the tumor microenvironment (TME) by modulating tumor-specific immune cells, make PDNVs promising anti-tumor therapeutics. With a lipid bilayer structure that allows drug loading and a transmembrane capacity readily endocytosed by cells, PDNVs are also expected to become a new drug delivery platform. Exogenous modifications of PDNVs enhance their circulating stability, tumor targeting ability, high cell endocytosis rate, and controlled-release capacity. In this review, we summarize PDNVs' natural antitumor activity, as well as engineered PDNVs as efficient precision-targeted drug delivery tools that enhance therapeutic effects. Additionally, we discuss critical considerations related to the issues raised in this area, which will encourage researchers to improve PDNVs as better anti-tumor therapeutics for clinic applications.

A new decontamination method for Bacillus subtilisin pasteurized milk: Thermosonication treatment.

Thermosonication (TS) is a novel and viable technique employed to replace conventional thermal processing. TS treatment combined with pasteurization was used to kill the residual heat-resistant Bacillus in pasteurized milk and extend the shelf life of pasteurized milk and compared with High Temperture Shoort Time (HTST) pasteurization to study its decontamination effect on Bacillus subtilis and the quality of treated milk. The results showed that after 40 kHz, 240 W, 25 min ultrasonic treatment and 50 °C heating decontamination treatment, the number of B. subtilis in the medium and milk medium decreased by 4.17 log CFU/mL and 4.09 log CFU/mL respectively. The results of cell membrane permeability showed that the leakage of DNA and protein in the HTST-TS group increased by 52.3 % and 34 %, respectively, when compared to that in the HTST group. In addition, transmission electron microscopy (TEM) analysis showed that the bacterial cell membrane of the HTST-TS group swelled up, the cell wall was ruptured, and the cell content was accumulated in the cells. The results showed that HTST-TS treatment significantly inhibited the activities of ATPase (47 %), succinate dehydrogenase (SDH) (68.6 %), and malate dehydrogenase (MDH) (54.4 %). The physical and chemical sensory evaluation of milk treated with HTST-TS showed that HTST-TS treatment could improve the L* value (2.24 %), zeta potential (64.19 %), and colloidal particle size (14.49 %) of milk but had no significant effect on oral sensitivity. In conclusion, this study provides new insights, which may be helpful in implementing this new combined decontamination method in the dairy industry to improve the quality of pasteurized milk and extend the its shelf life.

Formation, characterization, and antigenicity of lecithin-ß-conglycinin complexes.

Lipid binding has been proposed to represent a functional property of many allergenic proteins. This study investigated the formation, characterization, and antigenicity of lecithin-ß-conglycinin complexes. The results indicate that lecithin was combined with ß-conglycinin via static quenching and primarily driven by hydrogen bonds and van der Waals forces. In addition, heat treatment reduced the antigenicity of complexes, as evidenced by changes in molecular weight and secondary and tertiary structures. It revealed that large aggregates developed and more hydrophobic regions were exposed for complexes after heat treatment, as well as a decrease in the ß-sheet contents and an increase in the ß-turn and random coil contents. Furthermore, the average particle size of the complexes increased with increased temperature treatment, and the morphology of the complexes exhibited an amorphous polymer. These findings shedlight on the interaction between lecithin and ß-conglycinin and help us understand the role of lecithin in allergic reactions.

Identification, taste characterization, and molecular docking study of a novel microbiota-derived umami peptide.

Umami peptides are an important taste substance in fermented foods. However, in the absence of known microbiota-derived umami peptides, the understanding of the umami mechanism remains unclear. Tetragenococcus halophilus, a dominant fermentation bacteria, may be an important source of umami peptides. Accordingly, T. halophilus fermentation broth was fractioned by ethanol precipitation, gel chromatography, and reverse phase-high performance liquid chromatography. The isolated peptide fraction with the most intense umami taste was screened by amino acid composition and sensory analyses. Finally, three novel microbiota-derived peptides (DFE, LAGE, and QLQ) were identified, synthesized, and characterized for taste. Among them, only DFE had umami and umami-enhancing abilities improving multiple tastes. Molecular docking studies indicated that DEF binds to T1R1/T1R3 receptors through hydrogen bonding and electrostatic interactions involving receptor residues Ser332, Ser256, ASN41, His125, etc. This study highlights the critical role of microbiota-derived peptides in the umami taste of fermented foods.

Iron deficiency anemia associated factors and early childhood caries in Qingdao.

BACKGROUND: Iron deficiency anemia (IDA) has been shown to be related to early childhood caries (ECC). However, data on the relationship, if any, between IDA-associated factors and ECC remain scant. This study aimed to explore the interplay between IDA-associated factors and ECC. METHODS: This study randomly sampled a total of 1598 children in Qingdao city, and analyzed the severity of ECC using decayed-missing-filled teeth index, while the rate of caries was analyzed following the WHO recommendations. The correlation between IDA and ECC was analyzed by both the chi-square test and Mann-Whitney U test. In addition, we designed an electronic questionnaire and employed the disordered multi-classification logistic regression to interrogate the relationship between the IDA-associated factors and ECC. RESULTS: Children with IDA had higher rates and severe ECC than those without IDA (p < 0.001). Children who were breastfed until 2 years old had a higher risk of IDA and ECC, compared to those who were not {OR 3.453 (1.681-7.094)}. Compared with children who had no history of IDA at the age of 2 years or below, those with IDA history had a higher risk of IDA and ECC {OR 8.762 (3.648-21.041)}. In addition, children who had a maternal history of IDA at pregnancy were at a higher risk of IDA and ECC compared to those who had no IDA history at pregnancy {OR 4.913 (2.934-8.226)}. Our data showed that children from a family with an annual income lower than 50,000 Renminbi (RMB) had a higher risk of IDA and ECC compared to those with an annual family income higher than 200,000 RMB {OR 3.421 (1.505-7.775)}. On the other hand, compared with children taking iron supplements, children who did not were at a higher risk of ECC and IDA {OR 5.602 (1.858-16.896)}. CONCLUSION: Factors such as low family income, history of IDA in children aged 2 years or younger, IDA history during pregnancy, children breastfed until 2 years old, and those not taking iron supplements were significantly associated with the occurrence of ECC and IDA.

Iron deficiency and early childhood caries: a systematic review and meta-analysis.

BACKGROUNDS: Previous surveys have found that children with iron deficiency (ID) were likely to suffer from early childhood caries (ECC). We aimed to assess the scientific evidence about whether ID is intrinsically related to ECC. METHODS: The medical subject headings (MeSH) terms and free words were searched on PubMed, Web of Science, Cochrane, China National Knowledge Infrastructure, Wanfang, and the Database for Chinese Technical Periodicals from March 2020 to September 2020. Two researchers independently screened the articles. Data extraction and cross-checking were performed for the studies that met the inclusion criteria. Meta-analysis was performed using the Cochrane Collaboration's Review Manager 5.3 software. RESULTS: After excluding duplication and irrelevant literature, 12 case-control studies were included in the study. The meta-analysis demonstrated that children with ECC were more likely to have ID (odds ratio [OR] = 2.63, 95% confidence interval [CI]: [1.85, 3.73], P < 0.001). There was no statistically significant association found between the level of serum ferritin and ECC (weighted mean difference (WMD) = -5.80, 95% CI: [-11.97, 0.37], P = 0.07). Children with ECC were more likely to have iron-deficiency anemia (OR = 2.74, 95% CI: [2.41,3.11], P < 0.001). The hemoglobin (HGB) levels in the ECC group were significantly lower compared with that in the ECC-free group (WMD = -9.96, 95% CI: [-15.45, -4.46], P = 0.0004). The mean corpuscular volume (MCV) levels in the ECC group were significantly lower compared with that in the ECC-free group (WMD = -3.72, 95% CI: [-6.65, -0.79], P = 0.01). CONCLUSIONS: ID was more prevalent in children with ECC, and the markers of iron status in the ECC group, such as serum ferritin, HGB, and MCV, were relatively lower than the ECC-free group.

Comparative proteomic analysis of three Lactobacillus plantarum strains under salt stress by iTRAQ.

BACKGROUND: Lactobacillus plantarum, a common species of lactic acid bacteria, is used to improve the flavor of traditional fermented food. Under salt stress, different strains of L. plantarum can respond differently. In this work, proteomics and bioinformatics analysis of L. plantarum strains (ATCC14917, FS5-5, and 208) grown under salt stress (240 g L-1 sodium chloride (NaCl)) were investigated based on the isobaric tags for relative and absolute quantitation method. RESULTS: Although 171 differentially expressed proteins (DEPs) were observed, only 44, 57, and 112 DEPs were identified in the strains ATCC14917, FS5-5, and 208 respectively. There were 33, 191, and 179 specific DEPs in ATCC14917 versus FS5-5, in 208 versus FS5-5, and in strain 208 versus ATCC14917 in 240 g L-1 NaCl. These DEPs indicate that the three strains, from pickles, fermented soybean paste, and fermented milk, may have different salt stress responses. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes analysis showed that most DEPs observed were involved in protein biosynthesis, nucleotide metabolism, and sugar metabolism. Twenty-six significantly different DEPs that were possibly associated with salt response were selected and further analyzed for gene expression level and pattern by quantitative reverse transcription polymerase chain reaction. Pyruvate kinase and cysteine desulfurase had similar expression patterns in all three strains; glutamate decarboxylase expression was upregulated in FS5-5 and significantly upregulated in strain 208; RNA polymerase subunit alpha was downregulated in FS5-5 but upregulated in strain 208. CONCLUSIONS: These results also showed that the salt stress response of strain 208 may involve higher numbers of genes than the other strains. This research provides a theoretical basis for improvement of salt tolerance of L. plantarum in industrial production. © 2020 Society of Chemical Industry.

Antifungal Activity of Magnesium Oxide Nanoparticles: Effect on the Growth and Key Virulence Factors of Candida albicans.

The aim of this research was to study the effects of different concentrations of magnesium oxide nanoparticles (MgO NPs) on the growth and key virulence factors of Candida albicans (C. albicans). The minimum inhibitory concentration (MIC) of MgO NPs against C. albicans was determined by the micro-broth dilution method. A time-kill curve of MgO NPs and C. albicans was established to investigate the ageing effect of MgO NPs on C. albicans. Crystal violet staining, the MTT assay, and inverted fluorescence microscopy were employed to determine the effects of MgO NPs on C. albicans adhesion, two-phase morphological transformation, biofilm biomass, and metabolic activity. The time-kill curve showed that MgO NPs had fungicidal and antifungal activity against C. albicans in a time- and concentration-dependent manner. Semi-quantitative crystal violet staining and MTT assays showed that MgO NPs significantly inhibited C. albicans biofilm formation and metabolic activity, and the difference was statistically significant (p < 0.001). Inverted fluorescence microscopy showed that MgO NPs could inhibit the formation of C. albicans biofilm hyphae. Adhesion experiments showed that MgO NPs significantly inhibited the initial adhesion of C. albicans (p < 0.001). This study demonstrates that MgO NPs can effectively inhibit the growth, initial adhesion, two-phase morphological transformation, and biofilm formation of C. albicans and is an antifungal candidate.