Small Molecule Nitazoxanide Inhibits Osteogenic Differentiation and Promotes Adipogenic Differentiation of Bone Marrow Mesenchymal Stem Cells.

OBJECTIVE: To investigate the potential effect of small molecule nitazoxanide (NTZ) on the osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). METHODS: Cell counting Kit-8 assay was used to examine the effect of NTZ on proliferation of BMSCs. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analysis were used to measure the expression of osteogenic and adipogenic marker gene. Alkaline phosphatase (ALP) staining and activity assay and Alizarin Red S (ARS) staining were used to investigate the effect of NTZ on osteogenesis. Oil red O (ORO) staining assay was used to assess the impact of NTZ on adipogenesis. RESULTS: NTZ significantly suppressed the osteogenic differentiation but promoted the adipogenic differentiation of BMSCs. Mechanistically, NTZ regulated osteogenic/adipogenic differentiation of BMSCs by inhibiting the Wnt/ß-catenin signalling pathway. The addition of Wnt/ß-catenin signalling pathway activator, lithium chloride, could reverse the effect of NTZ on BMSCs. CONCLUSION: NTZ affected osteogenic and adipogenic differentiation of BMSCs with the involvement of Wnt/ß-catenin signalling pathway. This finding expanded the understanding of NTZ pharmacology and indicated that NTZ might have an adverse effect on bone homeostasis.

Glide path enlargement of curved molar canals using HyFlex EDM glide path file versus PathFile: a comparative study of preparation time and postoperative pain.

BACKGROUND: This randomized clinical trial aimed to compare the preparation time and severity of postoperative pain between HyFlex Electric Discharge Machine (EDM) glide path file (GPF) and PathFile. METHODS: Eighty patients whose molar teeth had at least one severely curved canal were treated by the same specialist. After access cavity preparation, the patients were randomly assigned to receive glide path enlargement with either HyFlex EDM GPF or PathFile. ProTaper Next X1 and X2 files were used to prepare the canals. The time of preparation was assessed and the severity of postoperative pain over the next 7 days was recorded. The preparation time and the postoperative pain scores were compared using the Linear Mixed Models (P ≤ 0.05). RESULTS: Glide path enlargement time was significantly shorter with HyFlex EDM GPF (27.828 ± 2.345 s) than with PathFile (48.942 ± 2.864 s) (P < 0.001). The highest postoperative pain score was recorded on the first day and the pain decreased over time in both groups. HyFlex EDM GPF group patients reported significantly less postoperative pain than PathFile group patients overall (P < 0.001). CONCLUSIONS: Postoperative pain and glide path preparation time could be reduced by using HyFlex EDM GPF system. Trial registration PKUSSNCT, PKUSSNCT-17B12, Registered 24 October 2017.

One-dimensional terahertz dielectric gradient metasurface for broadband spoof surface plasmon polaritons couplers: publisher's note.

This publisher's note contains corrections to Opt. Lett.46, 290 (2021)OPLEDP0146-959210.1364/OL.412229.

One-dimensional terahertz dielectric gradient metasurface for broadband spoof surface plasmon polaritons couplers.

At present, most of the gradient metasurfaces used to construct surface plasmon polaritons (SPPs)/spoof SPPs (SSPs) couplers are usually compact metal antennas working under reflection and transmission. In reflection mode, meta-couplers link propagating waves and surface waves (SWs), and SWs will undergo significant scattering before coupling to an Eigen SPP in the target system. In transmission mode, metal meta-couplers will encounter complex multilayer designing at the microwave/terahertz region and metal absorption loss at optical frequencies. In this Letter, to the best of our knowledge, a novel design using dielectric gradient metasurfaces instead of metal metasurface couplers is proposed to excite broadband SSPs on the metal groove array. We demonstrate that the well-designed phase dielectric gradient metasurface converts the normal incident terahertz wave to the predetermined angle in the dielectric substrate and then excites the broadband SSPs with the transmission coupling between the dielectric meta-coupler and SSPs surface. This research may open up new avenues in simple and broadband plane dielectric meta-couplers for SSPs in ultra-thin and compact functional devices for versatile applications.

Phase transformation behaviors and mechanical properties of NiTi endodontic files after gold heat treatment and blue heat treatment.

WaveOne Gold, ProTaper Gold, Reciproc Blue, ProTaper Next, WaveOne and ProTaper files were selected to compare the phase transformation behaviors and mechanical properties of nickel-titanium (NiTi) rotary files after gold heat and blue heat treatments. The reverse transformation finishing point temperatures of WaveOne Gold, ProTaper Gold, ProTaper Next and WaveOne were higher than those of the other two instruments investigated. At a deflection of 0.5 mm, the loads were significantly varied except for ProTaper Next and ProTaper Gold. At a deflection of 3.0 mm, the loads of Reciproc Blue and WaveOne Gold were significantly varied compared to WaveOne and ProTaper. Cycles to failure were reduced in the order of WaveOne Gold, Reciproc Blue, ProTaper Gold, ProTaper Next, WaveOne and ProTaper. NiTi instruments after gold heat and blue heat treatments exhibited significantly higher bending properties and cyclic fatigue resistances, representing an improved performance over traditional and M-wire instruments.

FHA2 is a plant-specific ISWI subunit responsible for stamen development and plant fertility.

Imitation Switch (ISWI) chromatin remodelers are known to function in diverse multi-subunit complexes in yeast and animals. However, the constitution and function of ISWI complexes in Arabidopsis thaliana remain unclear. In this study, we identified forkhead-associated domain 2 (FHA2) as a plant-specific subunit of an ISWI chromatin-remodeling complex in Arabidopsis. By in vivo and in vitro analyses, we demonstrated that FHA2 directly binds to RLT1 and RLT2, two redundant subunits of the ISWI complex in Arabidopsis. The stamen filament is shorter in the fha2 and rlt1/2 mutants than in the wild type, whereas their pistil lengths are comparable. The shorter filament, which is due to reduced cell size, results in insufficient pollination and reduced fertility. The rlt1/2 mutant shows an early-flowering phenotype, whereas the phenotype is not shared by the fha2 mutant. Consistent with the functional specificity of FHA2, our RNA-seq analysis indicated that the fha2 mutant affects a subset of RLT1/2-regulated genes that does not include genes involved in the regulation of flowering time. This study demonstrates that FHA2 functions as a previously uncharacterized subunit of the Arabidopsis ISWI complex and is exclusively involved in regulating stamen development and plant fertility.

A plant-specific SWR1 chromatin-remodeling complex couples histone H2A.Z deposition with nucleosome sliding.

Deposition of H2A.Z in chromatin is known to be mediated by a conserved SWR1 chromatin-remodeling complex in eukaryotes. However, little is known about whether and how the SWR1 complex cooperates with other chromatin regulators. Using immunoprecipitation followed by mass spectrometry, we found all known components of the Arabidopsis thaliana SWR1 complex and additionally identified the following three classes of previously uncharacterized plant-specific SWR1 components: MBD9, a methyl-CpG-binding domain-containing protein; CHR11 and CHR17 (CHR11/17), ISWI chromatin remodelers responsible for nucleosome sliding; and TRA1a and TRA1b, accessory subunits of the conserved NuA4 histone acetyltransferase complex. MBD9 directly interacts with CHR11/17 and the SWR1 catalytic subunit PIE1, and is responsible for the association of CHR11/17 with the SWR1 complex. MBD9, TRA1a, and TRA1b function as canonical components of the SWR1 complex to mediate H2A.Z deposition. CHR11/17 are not only responsible for nucleosome sliding but also involved in H2A.Z deposition. These results indicate that the association of the SWR1 complex with CHR11/17 may facilitate the coupling of H2A.Z deposition with nucleosome sliding, thereby co-regulating gene expression, development, and flowering time.

The PEAT protein complexes are required for histone deacetylation and heterochromatin silencing.

In eukaryotes, heterochromatin regions are typically subjected to transcriptional silencing. DNA methylation has an important role in such silencing and has been studied extensively. However, little is known about how methylated heterochromatin regions are subjected to silencing. We conducted a genetic screen and identified an epcr (enhancer of polycomb-related) mutant that releases heterochromatin silencing in Arabidopsis thaliana We demonstrated that EPCR1 functions redundantly with its paralog EPCR2 and interacts with PWWP domain-containing proteins (PWWPs), AT-rich interaction domain-containing proteins (ARIDs), and telomere repeat binding proteins (TRBs), thus forming multiple functionally redundant protein complexes named PEAT (PWWPs-EPCRs-ARIDs-TRBs). The PEAT complexes mediate histone deacetylation and heterochromatin condensation and thereby facilitate heterochromatin silencing. In heterochromatin regions, the production of small interfering RNAs (siRNAs) and DNA methylation is repressed by the PEAT complexes. The study reveals how histone deacetylation, heterochromatin condensation, siRNA production, and DNA methylation interplay with each other and thereby maintain heterochromatin silencing.

Post endodontic pain following single-visit root canal preparation with rotary vs reciprocating instruments: a meta-analysis of randomized clinical trials.

BACKGROUND: In endodontic therapy, continuous rotary instrumentation reduced debris compared to reciprocal instrumentation, which might affect the incidence of post-endodontic pain (PP). The aim of our study was to assess whether PP incidence and levels were influenced by the choice of rotary or reciprocal instruments. METHODS: In this meta-analysis the Pubmed and EM databases were searched for prospective clinical randomized trials published before April 20, 2016, using combinations of the keywords: root canal preparation/instrumentation/treatment/therapy; post-operative/endodontic pain; reciprocal and rotary instruments. RESULTS: Three studies were included, involving a total of 1,317 patients, 659 treated with reciprocating instruments and 658 treated with rotary instruments. PP was reported in 139 patients in the reciprocating group and 172 in the rotary group. The PP incidence odds ratio was 1.27 with 95% confidence interval (CI) (0.25, 6.52) favoring rotary instruments. The mild, moderate and severe PP levels odds ratios were 0.31 (0.11, 0.84), 2.24 (0.66, 7.59) and 11.71 (0.63, 218.15), respectively. No evidence of publication bias was found. CONCLUSIONS: Rotary instrument choice in endodontic therapy is associated with a lower incidence of PP than reciprocating instruments, while reciprocating instruments are associated with less mild PP incidence.

The Arabidopsis acetylated histone-binding protein BRAT1 forms a complex with BRP1 and prevents transcriptional silencing.

Transposable elements and other repetitive DNA sequences are usually subject to DNA methylation and transcriptional silencing. However, anti-silencing mechanisms that promote transcription in these regions are not well understood. Here, we describe an anti-silencing factor, Bromodomain and ATPase domain-containing protein 1 (BRAT1), which we identified by a genetic screen in Arabidopsis thaliana. BRAT1 interacts with an ATPase domain-containing protein, BRP1 (BRAT1 Partner 1), and both prevent transcriptional silencing at methylated genomic regions. Although BRAT1 mediates DNA demethylation at a small set of loci targeted by the 5-methylcytosine DNA glycosylase ROS1, the involvement of BRAT1 in anti-silencing is largely independent of DNA demethylation. We also demonstrate that the bromodomain of BRAT1 binds to acetylated histone, which may facilitate the prevention of transcriptional silencing. Thus, BRAT1 represents a potential link between histone acetylation and transcriptional anti-silencing at methylated genomic regions, which may be conserved in eukaryotes.

Modification of polyethylene with Pluronics F127 for improvement of blood compatibility.

In order to improve blood compatibility of polyethylene (PE) film, the Pluronics F127 additives in the PE film were then crosslinked to be stably entrapped in the PE matrix. The crosslinking was done by free radicals produced from the decomposition of dicumyl peroxide (DCP) in the film through heating (120 degrees C). Surface properties of the Pluronics F127 additive-containing PE films were investigated by Fourier transform infrared spectroscopy (FTIR), electron spectroscopy for chemical analysis (ESCA) and water contact angle (WCA) measurements. The blood compatibility of the Pluronics F127 additive-containing films was evaluated by platelet-rich plasma and blood-cell adhesion tests, respectively. And the results were observed by scanning electron microscopy. The blood compatibility of the prepared Pluronics F127 additive-containing film is better than that of blank PE film. These results suggest that the blood compatibility of Pluronics F127 additive-containing films make them suitable biomaterials for some applications.

[Prevalence of dental erosion and associated drinks in 12-year-old population of Beijing].

OBJECTIVE: To investigate the prevalence of dental erosion and associated drinks in 12-year-old adolescence of Beijing. METHODS: A random sample of 12-year-old adolescence of Beijing (n=844) was examined for dental erosion and required to fill a questionnaire of acidic drink intake. The grade criteria suitable for the survey of the dental erosion was used in the study. RESULTS: The prevalence of dental erosion was 61.8%, of which mild enamel was 74.1%, severe enamel erosion 24.9% and dentine erosion 1.0%. Statistic analysis showed that a large amount of intake of carbonated drink or juice were risk factors. CONCLUSIONS: Attention should be paid to the prevalence of dental erosion among Chinese adolescence.

[Pilot study of dental erosion and associated factors in university student volunteers].

OBJECTIVE: To investigate dental erosion and associated etiologic factors among students from one university. METHODS: A total of 179 student volunteers from one university were examined clinically for their dental erosion. Each was required to complete a questionnaire regarding potentially associated etiologic factors. A modified criteria was used to grade the severity of dental erosion. RESULTS: The prevalence of dental erosion of this group was 45.8%, mostly in enamel. Facial surfaces of anterior teeth were most vulnerable to erosion. Statistic analysis indicated that acidic diets, such as carbonated drink, fruit juice, fruit drink and banana were risk factors to dental erosion. CONCLUSIONS: The findings strongly suggest that much attention should be given to dental erosion which was probably associated with acidic diet.