Terpene produced by coexpression of the TPS and P450 genes from Lavandula angustifolia protects plants from herbivore attacks during budding stages.

To deter herbivore attacks, plants employ a diverse array of volatile compounds, particularly during the early developmental stages. The highly expressed genes LaTPS7, LaTPS8, and LaCYP71D582 were identified during the budding phases of Lavandula angustifolia. In vitro studies revealed that LaTPS7 generated nine distinct compounds, including camphene, myrcene, and limonene. LaTPS8 enzymatically converted eight volatiles by utilizing geranyl diphosphate and nerolidyl diphosphate as substrates. Overexpression of plastid-localized LaTPS7 in Nicotiana benthamiana resulted in the production of limonene. Furthermore, the endoplasmic reticulum-associated enzyme LaCYP71D582 potentially converted limonene into carveol. In N. benthamiana, LaTPS8 is responsible for the synthesis of α-pinene and sylvestrene. Furthermore, leaves transfected with LaTPS7 and leaves cotransfected with LaTPS7 and LaCYP71D582 exhibited a repellent effect on aphids, with an approximate rate of 70%. In comparison, leaves with an empty vector displayed a repellent rate of approximately 20%. Conversely, tobacco leaves expressing LaTPS7 attracted ladybugs at a rate of 48.33%, while leaves coexpressing LaTPS7 and LaCYP71D582 attracted ladybugs at a slightly higher rate of 58.33%. Subsequent authentic standard tests confirmed that limonene and carveol repel Myzus persicae while attracting Harmonia axyridis. The promoter activity of LaTPS7 and LaCYP71D582 was evaluated in Arabidopsis thaliana using GUS staining, and it was observed that wounding stimulated the expression of LaTPS7. The volatile compounds produced by LaTPS7, LaTPS8, and LaCYP71D582 play a crucial role in plant defence mechanisms. In practical applications, employing biological control measures based on plant-based approaches can promote human and environmental health.

Decoupling subgenomes within hybrid lavandin provide new insights into speciation and monoterpenoid diversification of Lavandula.

Polyploidization and transposon elements contribute to shape plant genome diversity and secondary metabolic variation in some edible crops. However, the specific contribution of these variations to the chemo-diversity of Lamiaceae, particularly in economic shrubs, is still poorly documented. The rich essential oils (EOs) of Lavandula plants are distinguished by monoterpenoids among the main EO-producing species, L. angustifolia (LA), L. × intermedia (LX) and L. latifolia (LL). Herein, the first allele-aware chromosome-level genome was assembled using a lavandin cultivar 'Super' and its hybrid origin was verified by two complete subgenomes (LX-LA and LX-LL). Genome-wide phylogenetics confirmed that LL, like LA, underwent two lineage-specific WGDs after the γ triplication event, and their speciation occurred after the last WGD. Chloroplast phylogenetic analysis indicated LA was the maternal source of 'Super', which produced premium EO (higher linalyl/lavandulyl acetate and lower 1,8-cineole and camphor) close to LA. Gene expression, especially the monoterpenoid biosynthetic genes, showed bias to LX-LA alleles. Asymmetric transposon insertions in two decoupling 'Super' subgenomes were responsible for speciation and monoterpenoid divergence of the progenitors. Both hybrid and parental evolutionary analysis revealed that LTR (long terminal repeat) retrotransposon associated with AAT gene loss cause no linalyl/lavandulyl acetate production in LL, and multi-BDH copies retained by tandem duplication and DNA transposon resulted in higher camphor accumulation of LL. Advances in allelic variations of monoterpenoids have the potential to revolutionize future lavandin breeding and EO production.

Integrated metabolomics and transcriptomics reveal glyphosate based-herbicide induced reproductive toxicity through disturbing energy and nucleotide metabolism in mice testes.

Glyphosate is a widely used herbicide that has deleterious effects on animal reproduction. However, details regarding the systematic mechanisms of glyphosate-induced reproductive toxicity are limited. This study aimed to investigate the toxic effects of glyphosate-based herbicide (GBH) on reproduction in mice exposed to 0 (control group), 50 (low-dose group), 250 (middle-dose group), and 500 (high-dose group) mg/kg/day GBH for 30 days. Toxicological parameters, metabolomics, and transcriptomics were performed to reveal GBH-induced reproductive toxicity. Our findings demonstrated that GBH exposure damaged mitochondrial pyknosis and the nuclear membrane of spermatogonia. GBH triggered a significant increase in sperm malformations in the high-dose group. Omics data showed that GBH impaired the Krebs cycle and respiratory chain, blocked pyruvate metabolism and glycolysis/gluconeogenesis, and influenced the pentose phosphate pathway and nucleotide synthesis and metabolism. Overall, the multi-omics results revealed systematic and comprehensive evidence of the adverse effects of GBH exposure, providing new insights into the reproductive toxicity of organophosphorus pesticides.

Multivariate prognostic analysis of direct pulp capping using a bioceramic material in mature permanent teeth with carious pulp exposure: a retrospective cohort study.

OBJECTIVES: On the basis of a large sample size and a long follow-up period, the objectives of this study were to evaluate the outcomes of direct pulp capping (DPC) in mature permanent teeth with carious pulp exposure using a kind of bioaggregate putty (BP) which commercially named iRoot BP Plus (Innovative Bioceramix, Inc., Vancouver, Canada) and to analyze the potential prognostic factors. MATERIALS AND METHODS: The design of this research was retrospective regarding treatment procedures and prospective regarding the assessment of outcomes. The preoperative diagnosis of the teeth was either normal pulp or reversible pulpitis. Results were assessed based on clinical and radiographic examinations with at least 12 months of follow-up after DPC. No symptoms or signs, a positive response to electric pulp testing, a normal response to cold pulp testing and radiographs showing no abnormalities were considered to indicate success. Kaplan-Meier survival analysis was used to calculate the cumulative survival of teeth after DPC. Univariate and multivariate Cox proportional hazard regressions were used to analyze potential prognostic factors. RESULTS: Three hundred thirty-four patients, including a total of 354 teeth, were available for the final clinical examination. The follow-up period ranged from 12 to 85 months, with an average of 27.0 ± 0.8 months. The total success rate was 85% (302/354), and the cumulative survival rates at 1, 2, 3, 4, and 5 years were 92%, 87%, 83%, 76%, and 72%, respectively. Univariate analysis indicated a significantly increased risk of failure in patients aged above 40 years and those treated by resident operators (P ≤ 0.01), with hazard ratios of 2.18 and 2.27, respectively. CONCLUSIONS: Under appropriate indication selection and treatment procedures, long-term success is possible in mature permanent teeth with carious pulp exposure by DPC using iRoot BP Plus. Patient age and operator experience are potential prognostic factors. CLINICAL RELEVANCE: Clinical data on iRoot BP Plus as a pulp capping medicament in mature permanent teeth with carious pulp exposure is lacking. This study indicated the efficacy of BP in DPC. Younger patient and sophisticated operator are beneficial for the outcome of DPC.

Comprehensive Analysis of Secondary Metabolites of Four Medicinal Thyme Species Used in Folk Medicine and Their Antioxidant Activities In Vitro.

Thyme is a colloquial term for number of aromatic species belonging to the genus Thymus L., known for their expressed biological activities and therefore used worldwide for seasoning and in folk medicine. In the present paper, the content of the total polyphenols (TP), total flavonoids (TF), and antioxidant capacity were assessed in the extracts of four traditionally used thyme species. Moreover, a comprehensive metabolomic study of thyme bioactive compounds was performed, and the obtained data were processed using multivariate statistical tests. The results clearly demonstrated the positive correlation between the content of the TP, TF, and antioxidant activity, and TF was more significant than TP. The findings revealed that four selected thyme species contained 528 secondary metabolites, including 289 flavonoids and 146 phenolic acids. Thymus marschallianus had a higher concentration of active ingredients, which improve its antioxidant capacity. Differentially accumulated metabolites were formed by complex pathways such as flavonoid, flavone, flavonol, isoflavonoid, and anthocyanin biosynthesis. Correlation analysis showed that 59 metabolites (including 28 flavonoids, 18 phenolic acids, and 7 terpenoid compounds) were significantly correlated with obtained values of the antioxidant capacity. The results suggested that selected thyme species exhibit a great diversity in antioxidant-related components, whereas flavonoids may be responsible for the high antioxidant capacity of all studied thyme species. The present study greatly expands our understanding of the complex phytochemical profiles and related applications of selected medicinal plants.

Splicing mutations in AMELX and ENAM cause amelogenesis imperfecta.

BACKGROUND: Amelogenesis imperfecta (AI) is a developmental enamel defect affecting the structure of enamel, esthetic appearance, and the tooth masticatory function. Gene mutations are reported to be relevant to AI. However, the mechanism underlying AI caused by different mutations is still unclear. This study aimed to reveal the molecular pathogenesis in AI families with 2 novel pre-mRNA splicing mutations. METHODS: Two Chinese families with AI were recruited. Whole-exome sequencing and Sanger sequencing were performed to identify mutations in candidate genes. Minigene splicing assays were performed to analyze the mutation effects on mRNA splicing alteration. Furthermore, three-dimensional structures of mutant proteins were predicted by AlphaFold2 to evaluate the detrimental effect. RESULTS: The affected enamel in family 1 was thin, rough, and stained, which was diagnosed as hypoplastic-hypomature AI. Genomic analysis revealed a novel splicing mutation (NM_001142.2: c.570 + 1G > A) in the intron 6 of amelogenin (AMELX) gene in family 1, resulting in a partial intron 6 retention effect. The proband in family 2 exhibited a typical hypoplastic AI, and the splicing mutation (NM_031889.2: c.123 + 4 A > G) in the intron 4 of enamelin (ENAM) gene was observed in the proband and her father. This mutation led to exon 4 skipping. The predicted structures showed that there were obvious differences in the mutation proteins compared with wild type, leading to impaired function of mutant proteins. CONCLUSIONS: In this study, we identified two new splicing mutations in AMELX and ENAM genes, which cause hypoplastic-hypomature and hypoplastic AI, respectively. These results expand the spectrum of genes causing AI and broaden our understanding of molecular genetic pathology of enamel formation.

Decomposing socioeconomic inequalities in dental caries among Chinese adults: findings from the 4th national oral health survey.

OBJECTIVE: This cross-sectional study aimed to investigate socioeconomic inequalities in dental caries among adults (35 years and older) in China and explore the contributions of various factors to these inequalities. METHODS: This study included 10,983 adults (3,674 aged 35-44 years, 3,769 aged 55-64 years and 3,540 aged 65-74 years) who participated in the 4th National Oral Health Survey (2015-2016) in China. Dental caries status was evaluated by the decayed, missing and filled teeth (DMFT) index. Concentration indices (CIs) were applied to quantify the different degrees of socioeconomic-related inequality in DMFT, decayed teeth with crown or root caries (DT), missing teeth due to caries or other reasons (MT), and filled teeth without any primary or secondary caries (FT) among adults of different age groups. Decomposition analyses were conducted to identify the determinants and their associations with inequalities in DMFT. RESULTS: The significant negative CI indicated that DMFT for the total sample were concentrated among socioeconomically disadvantaged adults (CI = - 0.06; 95% confidence interval [CI], - 0.073 to - 0.047). The CIs for DMFT for adults aged 55-64 and 65-74 years were - 0.038 (95% CI, - 0.057 to - 0.018) and - 0.039 (95% CI, - 0.056 to - 0.023), respectively, while the CI for DMFT for adults aged 35-44 years was not statistically significant (CI = - 0.002; 95% CI, - 0.022 to 0.018). The concentration indices of DT were negative and concentrated in disadvantaged populations, while FT showed pro-rich inequalities in all age groups. Decomposition analyses showed that age, education level, toothbrushing frequency, income and type of insurance contributed substantially to socioeconomic inequalities, accounting for 47.9%, 29.9%, 24.5%,19.1%, and 15.3%, respectively. CONCLUSION: Dental caries was disproportionately concentrated among socioeconomically disadvantaged adults in China. The results of these decomposition analyses are informative for policy-makers attempting to develop targeted health policy recommendations to reduce dental caries inequalities in China.

The transcription factor LaMYC4 from lavender regulates volatile Terpenoid biosynthesis.

BACKGROUND: The basic helix-loop-helix (bHLH) transcription factors (TFs), as one of the largest families of TFs, are essential regulators of plant terpenoid biosynthesis and response to stresses. Lavender has more than 75 volatile terpenoids, yet few TFs have been identified to be involved in the terpenoid biosynthesis. RESULTS: Based on RNA-Seq, reverse transcription-quantitative polymerase chain reaction, and transgenic technology, this study characterized the stress-responsive transcription factor LaMYC4 regulates terpenoid biosynthesis. Methyl jasmonate (MeJA) treatment increased volatile terpenoid emission, and the differentially expressed gene LaMYC4 was isolated. LaMYC4 expression level was higher in leaf than in other tissues. The expression of LaMYC4 decreased during flower development. The promoter of LaMYC4 contained hormone and stress-responsive regulatory elements and was responsive to various treatments, including UV, MeJA treatment, drought, low temperature, Pseudomonas syringae infection, and NaCl treatment. LaMYC4 overexpression increased the levels of sesquiterpenoids, including caryophyllenes, in Arabidopsis and tobacco plants. Furthermore, the expression of crucial node genes involved in terpenoid biosynthesis and glandular trichome number and size increased in transgenic tobacco. CONCLUSIONS: We have shown that the stress-responsive MYC TF LaMYC4 from 'Jingxun 2' lavender regulates volatile terpenoid synthesis. This study is the first to describe the cloning of LaMYC4, and the results help understand the role of LaMYC4 in terpenoid biosynthesis.

Time-series transcriptome provides insights into the gene regulation network involved in the volatile terpenoid metabolism during the flower development of lavender.

BACKGROUND: Essential oils (EOs) of Lavandula angustifolia, mainly consist of monoterpenoids and sesquiterpenoids, are of great commercial value. The multi-flower spiciform thyrse of lavender not only determines the output of EOs but also reflects an environmental adaption strategy. With the flower development and blossom in turn, the fluctuation of the volatile terpenoids displayed a regular change at each axis. However, the molecular mechanism underlying the regulation of volatile terpenoids during the process of flowering is poorly understood in lavender. Here, we combine metabolite and RNA-Seq analyses of flowers of five developmental stages at first- and second-axis (FFDSFSA) and initial flower bud (FB0) to discover the active terpenoid biosynthesis as well as flowering-related genes. RESULTS: A total of 56 mono- and sesquiterpenoids were identified in the EOs of L. angustifolia 'JX-2'. FB0' EO consists of 55 compounds and the two highest compounds, ß-trans-ocimene (20.57%) and (+)-R-limonene (17.00%), can get rid of 74.71 and 78.41% aphids in Y-tube olfactometer experiments, respectively. With sequential and successive blossoms, temporally regulated volatiles were linked to pollinator attraction in field and olfaction bioassays. In three characteristic compounds of FFDSFSA' EOs, linalyl acetate (72.73%) and lavandulyl acetate (72.09%) attracted more bees than linalool (45.35%). Many transcripts related to flowering time and volatile terpenoid metabolism expressed differently during the flower development. Similar metabolic and transcriptomic profiles were observed when florets from the two axes were maintained at the same maturity grade. Besides both compounds and differentially expressed genes were rich in FB0, most volatile compounds were significantly correlated with FB0-specific gene module. Most key regulators related to flowering and terpenoid metabolism were interconnected in the subnetwork of FB0-specific module, suggesting the cross-talk between the two biological processes to some degree. CONCLUSIONS: Characteristic compounds and gene expression profile of FB0 exhibit ecological value in pest control. The precise control of each-axis flowering and regular emissions at transcriptional and metabolic level are important to pollinators attraction for lavender. Our study sheds new light on lavender maximizes its fitness from "gene-volatile terpenoid-insect" three layers.

Regulation of cellulase expression, sporulation, and morphogenesis by velvet family proteins in Trichoderma reesei.

Homologs of the velvet protein family are encoded by the ve1, vel2, and vel3 genes in Trichoderma reesei. To test their regulatory functions, the velvet protein-coding genes were disrupted, generating Δve1, Δvel2, and Δvel3 strains. The phenotypic features of these strains were examined to identify their functions in morphogenesis, sporulation, and cellulase expression. The three velvet-deficient strains produced more hyphal branches, indicating that velvet family proteins participate in the morphogenesis in T. reesei. Deletion of ve1 and vel3 did not affect biomass accumulation, while deletion of vel2 led to a significantly hampered growth when cellulose was used as the sole carbon source in the medium. The deletion of either ve1 or vel2 led to the sharp decrease of sporulation as well as a global downregulation of cellulase-coding genes. In contrast, although the expression of cellulase-coding genes of the ∆vel3 strain was downregulated in the dark, their expression in light condition was unaffected. Sporulation was hampered in the ∆vel3 strain. These results suggest that Ve1 and Vel2 play major roles, whereas Vel3 plays a minor role in sporulation, morphogenesis, and cellulase expression.

Promoting bond durability by a novel fabricated bioactive dentin adhesive.

OBJECTIVE: To prepare a bioactive dentin adhesive and investigate its effect on promoting bonding durability of dentin. METHODS: The mineralization of the bioactive glass with high phosphorus (10.8 mol% P2O5-54.2 mol% SiO2-35 mol% CaO, named PSC) and its ability to induce type I collagen mineralization were observed by SEM and TEM. The Control-Bond and the bioactive dentin adhesive containing 20 wt% PSC particles (PSC-Bond) were prepared, and their degree of conversion (DC), microtensile bond strength (µTBS), film thickness and mineralization performance were evaluated. To evaluate the bonding durability, dentin bonding samples were prepared by Control-Bond and PSC-Bond, and mineralizated in simulated body fluid for 24 h, 3 months, and 6 months. Then, the long-term bond strength and microleakage at the adhesive interface of dentin bonding samples were evaluated by microtensile testing and semiquantitative ELIASA respectively. RESULTS: The PSC showed superior mineralization at 24 h and induced type I collagen mineralization to some extent under weakly alkaline conditions. For PSC-Bond, DC was 62.65 ± 1.20%, µTBS was 39.25 ± 4.24 MPa and film thickness was 17.00 ± 2.61 µm. PSC-Bond also formed hydroxyapatite and maintained good mineralization at the bonding interface. At 24 h, no significant differences in µTBS and interface microleakage were observed between the Control-Bond and PSC-Bond groups. After 6 months of aging, the µTBS was significantly higher and the interface microleakage was significantly lower of PSC-Bond group than those of Control-Bond group. SIGNIFICANCE: PSC-Bond maintained bond strength stability and reduced interface microleakage to some extent, possibly reducing the occurrence of secondary caries, while maintaining long-term effectiveness of adhesive restorations.

Genome-wide identification and expression of BAHD acyltransferase gene family shed novel insights into the regulation of linalyl acetate and lavandulyl acetate in lavender.

The BAHD acyltransferase superfamily has a variety of biological functions, especially in catalyzing the synthesis of ester compounds and improving plant stress resistance. Linalyl acetate and lavandulyl acetate, the most important volatile esters in lavender, are generated by LaBAHDs. However, the systematic identification, expression characteristics of LaBAHD genes and their correlations with ester formation remain elusive. Here, 166 LaBAHD genes were identified from the lavender genome. Based on detailed phylogenetic analysis, the LaBAHD family genes were divided into five groups, among which the LaBAHDs involved in volatile ester biosynthesis belong to the IIIa and Va clades. Whole-genome duplications (WGDs) and tandem duplications (TDs) jointly drive the expansion of LaBAHD superfamily. The promoter regions of LaBAHDs contained a variety of stress- and hormone-related motifs, as well as binding sites with five types of transcription factors (TFs). Then, linalyl acetate- and lavandulyl acetate-regulated coexpression modules were established and some candidate TFs that may function in inducing ester formation were identified. Based on the correlation analysis between the ester contents and expression profiles of BAHD genes in different tissues, five candidate genes were screened for further examination. Drought, salt and MeJA treatments increased the accumulation of linalyl acetate and lavandulyl acetate, and induced the expression of LaBAHDs. Our results indicated that LaBAHD57, LaBAHD63, LaBAHD104, LaBAHD105 and LaBAHD119 are crucial candidate genes involved in linalyl acetate and lavandulyl acetate biosynthesis. Our findings offer a theoretical foundation for further studying the specific biological functions of LaBAHD family and improving the quality of lavender essential oil.

LaMYC7, a positive regulator of linalool and caryophyllene biosynthesis, confers plant resistance to Pseudomonas syringae.

Linalool and caryophyllene are the main monoterpene and sesquiterpene compounds in lavender; however, the genes regulating their biosynthesis still remain many unknowns. Here, we identified LaMYC7, a positive regulator of linalool and caryophyllene biosynthesis, confers plant resistance to Pseudomonas syringae. LaMYC7 was highly expressed in glandular trichomes, and LaMYC7 overexpression could significantly increase the linalool and caryophyllene contents and reduce susceptibility to P. syringae in Nicotiana. In addition, the linalool possessed antimicrobial activity against P. syringae growth and acted dose-dependently. Further analysis demonstrated that LaMYC7 directly bound to the promoter region of LaTPS76, which encodes the terpene synthase (TPS) for caryophyllene biosynthesis, and that LaTPS76 was highly expressed in glandular trichomes. Notably, the LaMYC7 promoter contained hormone and stress-responsive regulatory elements and responded to various treatments, including ultraviolet, low temperature, salt, drought, methyl jasmonate, and P. syringae infection treatments. Under these treatments, the changes in the linalool and caryophyllene contents were similar to those in LaMYC7 transcript abundance. Based on the results, LaMYC7 could respond to P. syringae infection in addition to being involved in linalool and caryophyllene biosynthesis. Thus, the MYC transcription factor gene LaMYC7 can be used in the breeding of high-yielding linalool and caryophyllene lavender varieties with pathogen resistance.

Heparin-Functionalized Bioactive Glass to Harvest Endogenous Growth Factors for Pulp Regeneration.

Pulp and periapical diseases can lead to the cessation of tooth development, resulting in compromised tooth structure and functions. Despite numerous efforts to induce pulp regeneration, effective strategies are still lacking. Growth factors (GFs) hold considerable promise in pulp regeneration due to their diverse cellular regulatory properties. However, the limited half-lives and susceptibility to degradation of exogenous GFs necessitate the administration of supra-physiological doses, leading to undesirable side effects. In this research, a heparin-functionalized bioactive glass (CaO-P2O5-SiO2-Heparin, abbreviated as PSC-Heparin) with strong bioactivity and a stable neutral pH is developed as a promising candidate to addressing challenges in pulp regeneration. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis reveal the successful synthesis of PSC-Heparin. Scanning electron microscopy and X-ray diffraction show the hydroxyapatite formation can be observed on the surface of PSC-Heparin after soaking in simulated body fluid for 12 h. PSC-Heparin is capable of harvesting various endogenous GFs and sustainably releasing them over an extended duration by the enzyme-linked immunosorbent assay. Cytological experiments show that developed PSC-Heparin can facilitate the adhesion, migration, proliferation, and odontogenic differentiation of stem cells from apical papillae. Notably, the histological analysis of subcutaneous implantation in nude mice demonstrates PSC-Heparin is capable of promoting the odontoblast-like layers and pulp-dentin complex formation without the addition of exogenous GFs, which is vital for clinical applications. This work highlights an effective strategy of harvesting endogenous GFs and avoiding the involvement of exogenous GFs to achieve pulp-dentin complex regeneration, which may open a new horizon for regenerative endodontic therapy.

[Growth ability of human dental pulp cells on three bioactive scaffolds].

OBJECTIVE: To investigate the proliferation and differentiation of the human dental pulp cells (hDPCs) on the bioactive scaffolds. METHODS: Primary HDPCs were harvested from impacted third molars of healthy adult individuals (18-25 years of age) by enzyme digestion, expanded and cultured. The cells used for this investigation were the 4 th passage. Immunohistochemical methods were used to verify that the cells were dental pulp cells. The expression of stromal precursor antigen-1 (STRO-1) was determined by flow cytometry. Three different types of scaffolds were used: collagen (COL), collagen / bioglass (COL-BG) and collagen / bioglass / polycaprolactone (COL-BG-PCL). Cell proliferation on the scaffolds was determined using a MTT assay at hour 6, on days 1, 3, 5, 7, 14 and 21. On day 14, the scaffolds were stained with the alkaline phosphatase (ALP) staining kit. RESULTS: The tested cells had STRO-1 positive cells. The proliferation of HDPCs was significantly higher on the COL-BG scaffold and COL-BG-PCL scaffold as compared with COL scaffold (P<0.05). Especially on days 14 and 21, the optical density value of bioglass composite scaffold were 5 times that of the COL scaffold. The ALP positive staining area was observed more extensively on the COL-BG scaffold and COL-BG-PCL scaffold than on the COL scaffold. CONCLUSION: As comparison with the COL scaffold, HDPCs' proliferation and differentiation present more activity on the COL-BG and COL-BG-PCL scaffolds.

Effect of a bioactive glass-based root canal sealer on root fracture resistance ability.

Background/purpose: The root fracture resistance of endodontically treated teeth is decreased significantly, and it is more likely to fracture. This study aimed to evaluate the effect of a novel root canal sealer based on bioactive glass (BG) on root fracture resistance and explore its mechanism. Materials and methods: The BG-based root canal sealer (BG Sealer) was prepared by mixing a kind of bioactive glass (10.8% P2O5, 54.2% SiO2, 35% CaO, mol.%, named PSC), zirconia (ZrO2) powder, sodium alginate (SA) and phosphate solution (PS). A pH meter was used to measure the pH of simulated body fluid (SBF) after immersion with BG Sealer at different time. After preparing the samples of BG sealer with a diameter of 4 mm and a height of 6 mm, the compressive strength was tested by a universal testing machine. The scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to detect and analyze the mineral status of root canal systems filled with BG Sealer. The push out test was used to measure the push out bond strength of BG Sealer. The fracture resistance of root canals filled with BG Sealer was detected by the compressive loading test. Bioceramic root canal sealer iRoot SP was set as the control group. Results: (1) Physicochemical properties: The pH value of SBF immersed with BG Sealer increased slightly up to 7.68, while the pH of SBF immersed with iRoot SP increased to 12.08. The compressive strength of the novel BG Sealer was 4.62 ± 1.70 MPa, which was lower than that of iRoot SP (P < 0.05). (2) Mineralization: The hydroxyapatite layers were observed on the surface of BG Sealer and iRoot SP after being immersed in SBF for 4 weeks. BG Sealer and iRoot SP were both able to penetrate into the dentin tubules, duplicate the morphology of root canals well, and form a layer of hydroxyapatite. (3) Adhesion to dentin: There was no significant difference between the push out bond strength of the novel BG Sealer and iRoot SP (P > 0.05). (4) Fracture resistance: After immersion in SBF for 4 weeks, the fracture resistance of roots filled with BG Sealer and iRoot SP was 454.16 ± 155.39 N and 445.50 ± 164.73 N, respectively, both of which were not statistically different from that of the roots unprepared and unfilled (394.07 ± 62.12 N) (P > 0.05), whereas higher than that of the roots prepared and unfilled (235.36 ± 83.80 N) (P < 0.05). Conclusion: The novel BG Sealer has good adhesion to the root dentin, can penetrate into the dentin tubules to generate minerals, and meanwhile can improve the fracture resistance of the roots after root canal treatment. It is expected to be a bioactive root canal sealer with good clinical application prospects.

The additive effects of bioactive glasses and photobiomodulation on enhancing bone regeneration.

Bioactive glasses (BG) have been generally used in bone defects repair for its good osteoinductivity and osteoconductivity. However, the early angiogenesis of BG in the repair of large-sized bone defects may not be sufficient enough to support new bone formation, resulting in the failure of bone repair. Photobiomodulation (PBM) therapy, which is superior on promoting early angiogenesis, may contribute to the angiogenesis of BG and further enhance the repair of bone defects. Therefore, we applied BG and PBM in combination and preliminarily investigated their additive effects on bone regeneration both in vitro and in vivo. The in vitro results revealed that BG combined with PBM remarkably enhanced human bone marrow mesenchymal stem cells proliferation, osteogenic-related genes expression and mineralization, which was better than applying BG or PBM respectively. For in vivo studies, the histological staining results showed that BG induced new bone formation in the interior of defects and promoted new bone reconstruction at 6 weeks post-operation. The micro-computed tomography results further confirmed that BG combined with PBM accelerated bone formation and maturation, improved the speed and quality of bone regeneration, and promoted bone repair. In conclusion, with the optimum BG and PBM parameters, BG combined with PBM generated additive effects on promoting bone regeneration.

Glyphosate based-herbicide disrupts energy metabolism and activates inflammatory response through oxidative stress in mice liver.

Glyphosate, the most widely used herbicide worldwide, has been reported to cause hepatotoxicity. However, these systematic mechanisms remain poorly understood. Here, we investigated the effects of glyphosate-based herbicides (GBH) on liver toxicity in mice exposed to 0, 50, 250, and 500 mg/kg/day GBH for 30 d. Pathological and ultrastructural changes, serum biochemical indicators, oxidative stress state, and transcriptome and key protein alterations were performed to describe the hepatic responses to GBH. GBH induced hepatocytes structural alterations, vacuolation, and inflammatory, mitochondrial swelling and vacuolization; damaged liver function and aggravated oxidative stress; blocked the respiratory chain, promoted gluconeogenesis, fatty acid synthesis and elongation, and activated complement and coagulation cascades system (CCCS) in the liver. Moreover, SOD, H2O2, and MDA were negatively correlated with the CxI and CxIV genes, but positively correlated with the genes in glucolipid metabolism and CCCS pathways; however, the opposite results were observed for CAT, GSH-Px, and T-AOC. Overall, this study revealed the systematic mechanism underlying hepatotoxicity caused by GBH, providing new insights into understanding the hepatotoxicity of organophosphorus pesticide.

Novel dentin sialophosphoprotein gene frameshift mutations affect dentin mineralization.

OBJECTIVE: This study aimed to identify candidate genes for inheritable dentin defects in three Chinese pedigrees and characterize the property of affected teeth. DESIGN: Clinical and radiological features were recorded for the affected individuals. Genomic DNA obtained from peripheral venous blood or saliva were analyzed by whole-exome sequencing. The density and microhardness of affected dentin was measured. Scanning electron microscopy (SEM) was also performed to obtain the microstructure phenotype. RESULTS: 1) General appearance: the affected dentitions shared yellowish-brown or milky color. Radiographs showed that the pulp cavity and root canals were obliterated in varying degrees or exhibited a pulp aspect in the 'thistle tube'. Some patients exhibited periapical infections without pulpal exposure, and some affected individuals showed shortened, abnormally thin roots accompanied by severe alveolar bone loss. 2) Genomic analysis: three new frameshift mutations (NM_014208.3: c.2833delA, c.2852delGand c.3239delA) were identified in exon 5 of dentin sialophosphoprotein (DSPP) gene, altering dentin phosphoprotein (DPP) as result. In vitro studies showed that the density and microhardness of affected dentin were decreased, the dentinal tubules were sparse and arranged disorderly, and the dentinal-enamel-junction (DEJ) was abnormal. CONCLUSIONS: In this study, we identified three novel frameshift mutations of dentin sialophosphoprotein gene related to inherited dentin defects. These mutations are speculated to cause abnormal coding of dentin phosphoprotein C-terminus, which affect dentin mineralization. These results expand the spectrum of dentin sialophosphoprotein gene mutations causing inheritable dentin defects and broaden our understanding of the biological mechanisms by which dentin forms.

Effective Improvement of the Oxidative Stability of Acer truncatum Bunge Seed Oil, a New Woody Oil Food Resource, by Rosemary Extract.

Acer truncatum Bunge is a versatile, oil-producing, woody tree natively and widely distributed in northern China. In 2011, The People's Republic of China's Ministry of Health certified Acer truncatum seed oil (Aoil) as a new food resource. Unsaturated fatty acids account for up to 92% of the entire Aoil. When Aoil is processed or stored, it can easily oxidize. In this study, the effects of rosemary (Rosmarinus officinalis L.) extract on the oxidation stability of Aoil were analysed from multiple angles. The results of radical scavenging ability, malondialdehyde, and free fatty acid reveal that rosemary crude extract (RCE), rosmarinic acid (RA), and carnosic acid (CA) can significantly inhibit the oxidation of Aoil, and CA has the best oxidative stability for Aoil among the tested components of the crude rosemary. The delayed oxidation ability of CA for Aoil was slightly weaker than that of tert-butylhydroquinone (TBHQ), but stronger than that of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α-tocopherol (α-T), which was confirmed by microstructures, kinematic viscosity, Aoil weight change, and functional group. Additionally, CA-enriched Aoil had the smallest content of volatile lipid oxidation products. Moreover, lecithin-CA particles were added to enhance the oxidative stability of Aoil. These findings show that CA is a potent antioxidant, capable of successfully preventing Aoil oxidation.