The mechanical, wear, antibacterial properties and biocompatibility of injectable restorative materials under wet challenge.

OBJECTIVES: To evaluate the mechanical, wear, antibacterial properties, and biocompatibility of injectable composite materials. METHODS: Two injectable composite resins (GU and BI), one flowable composite resin (FS), and one flowable compomer (DF), in A2 shade, were tested. Mechanical properties were tested via three-point bending test immediately after preparation and after 1-day, 7-day, 14-day, and 30-day water storage. Under water-PMMA slurry immersion, specimens were subjected to a 3-body wear test (10,000 cycles) against stainless steel balls, while the roughness, wear depth, and volume loss were recorded. After 1-day and 3-day MC3T3-E1 cell culture, cell viability was evaluated with CCK-8 test kits, while the cell morphology was observed under CLSM and SEM. Antibacterial properties on S. mutans were assessed via CFU counting, CLSM, and SEM observation. SPSS 26.0 was used for statistical analysis (α = 0.05). RESULTS: The mechanical properties were material-dependent and sensitive to water storage. Flexural strength ranked GU > FS > BI > DF at all testing levels. Three nanocomposites had better wear properties than DF. No significant difference on 1-day cell viability was found, but DF showed significantly lower cell proliferation than nanocomposites on 3-day assessment. GU and FS had more favourable cell adhesion and morphology. CFU counting revealed no significant difference, while FS presented a slightly thicker biofilm and BI showed relatively lower bacteria density. CONCLUSIONS: Injectable nanocomposites outperformed the compomer regarding mechanical properties, wear resistance, and biocompatibility. The tested materials presented comparable antibacterial behaviours. Flowable resin-based composites' performances are affected by multiple factors, and their compositions can be attributed. CLINICAL SIGNIFICANCE: A profound understanding of the mechanical, wear, and biological properties of the restorative material is imperative for the clinical success of dental restorations. The current study demonstrated superior properties of highly filled injectable composite resins, which imply their wider indications and better long-term clinical performances.

Transcription factors NtHD9 and NtHD12 control long glandular trichome formation via jasmonate signaling.

Glandular trichomes are universal epidermal structures that produce abundant specialized metabolites. However, knowledge of the initiation of glandular heads in glandular trichomes is limited. Herein, we found an intrinsic link of morphogenesis between glandular trichomes and non-glandular trichomes. Two novel homeodomain leucine zipper II members in tobacco (Nicotiana tabacum), NtHD9 and NtHD12, played important roles in long glandular trichome formation: NtHD9 was responsible for glandular head formation, while NtHD12 simultaneously controlled the formation of stalks and glandular heads. DAP-seq analysis suggested that NtHD9 can bind to the KKGCATTWAWTR motif of the cytochromes P450 94C1 (NtCYP94C1) promoter, which is involved in jasmonoyl-isoleucine oxidation. RNA-seq analysis of non-transformed tobacco and nthd9 plants revealed that NtHD9 modulates the expression of jasmonate (JA) signaling- and six trichome development-related genes. Notably, MeJA treatment restored the morphogenesis of long glandular trichomes in nthd9 and nthd12 plants, and the size of glandular heads increased with increasing MeJA concentration. However, the phenotype of long glandular trichome absence in double mutants of NtHD9 and NtHD12 could not be restored by MeJA. Our data demonstrate that NtHD9 and NtHD12 have distinct major functions yet overlapping roles in long glandular trichome formation via JA signaling.

Construction of Z-scheme CdS/Ag/TiO2 NTs photocatalysts for photocatalytic dye degradation and hydrogen evolution.

The ternary CdS/Ag/TiO2 NTs photocatalysts with indirect Z-scheme heterojunctions were synthesized by the photoreduction deposition of Ag and successive ionic layer adsorption and reaction (SILAR) of CdS on TiO2 nanotube arrays (TiO2 NTs). The elemental composition, microstructure, photoresponse and photoelectrochemical property of the photocatalyst were systematically characterized. The results proved that compared with binary heterojunction, the light absorption range of the ternary CdS/Ag/TiO2 NTs photocatalyst was significantly extended, and the photoelectron transportation efficiency was improved. Under sunlight irradiation, the photocatalytic capacity was verified by investigating the photodegradation of MB and RhB dyes. The CdS/Ag/TiO2 NTs exhibited the optimal photocatalytic performance with the degradation efficiency of 82.24% for RhB and 100% for MB. The synthesized CdS/Ag/TiO2 NTs had high photocatalytic hydrogen evolution capacity and stability, and the hydrogen production reached 806.33 µmol·cm-2. Based on the results of electron spin resonance spectroscopy (ESR) and free radical trapping, the photocatalytic reaction mechanism was explained. The synthesis of ternary CdS/Ag/TiO2 NTs provides a practical reference and guidance for designing high-efficient photocatalysts with Z-scheme heterojunctions toward solar energy development for H2 generation, pollutant remediation and photoelectric conversion.