A hnRNPA2B1 agonist effectively inhibits HBV and SARS-CoV-2 omicron in vivo

The twenty-first century has already recorded more than ten major epidemics or pandemics of viral disease, including the devastating COVID-19. Novel effective antivirals with broad-spectrum coverage are urgently needed. Herein, we reported a novel broad-spectrum antiviral compound PAC5. Oral administration of PAC5 eliminated HBV cccDNA and reduced the large antigen load in distinct mouse models of HBV infection. Strikingly, oral administration of PAC5 in a hamster model of SARS-CoV-2 omicron (BA.1) infection significantly decreases viral loads and attenuates lung inflammation. Mechanistically, PAC5 binds to a pocket near Asp49 in the RNA recognition motif of hnRNPA2B1. PAC5-bound hnRNPA2B1 is extensively activated and translocated to the cytoplasm where it initiates the TBK1-IRF3 pathway, leading to the production of type I IFNs with antiviral activity. Our results indicate that PAC5 is a novel small-molecule agonist of hnRNPA2B1, which may have a role in dealing with emerging infectious diseases now and in the future.

The potential effect of proanthocyanidins on the stability of resin-dentin bonds against thermal cycling / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the potential effect of proanthocyanidins (PA), a natural cross-linker, on the stability of resin-dentin bonds against thermal cycling.</p><p><b>METHODS</b>Ten percent, 15% PA-based preconditioners, and 5% glutaraldehyde were prepared for the transient pretreatment of demineralized dentin before bonding. Specimens without pretreatment were used as negative controls (n = 4 teeth for each group). Microtensile bond strength, failure mode, micromorphologies of resin-dentin interface and the collagen degradation of bonded specimens after thermal cycling were evaluated.</p><p><b>RESULTS</b>After thermal cycling, the microtensile bond strength values of resin-dentin bond in groups pretreated with 15% PA for 120 s and 60 s [(23.09 ± 3.19) and (21.88 ± 3.49) MPa] were significantly higher than that in control group [(15.47 ± 3.78) MPa] (P < 0.05). Mixed fractures were the most prevalent failure mode. Specimens with pretreatment presented compact hybrid layer, while some narrow gaps were found in hybrid layer of non-treated specimens. Collagen biodegradation rates in groups with pretreatment were significantly lower than that in control group (P < 0.05). Among them, specimens pretreated by 15% PA preconditioner for 120 s exhibited the lowest biodegradation rates [(0.316 ± 0.019) mg/g].</p><p><b>CONCLUSIONS</b>The application of natural cross-linker PA on demineralized dentin reduced the bond degradation against aging by thermal cycling, and can be helpful to create more durable bonds to dentin.</p>

A study on the bonding properties of four resin cements / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the dentin and enamel bonding strength and resin-dentin interfaces of four resin cements.</p><p><b>METHODS</b>Twenty-four sound freshly extracted molars were sectioned with low-speed saw under running water. Two mesial-distal enamel disc and two buccal-lingual dentin discs were sectioned from each molar. Four resin cements (A group: Panavia(TM) F; B group: RelyX(TM) ARC; C group: RelyX(TM) Unicem; D group: Clearfil(TM) SA Cement) were applied to the surface of these enamel and dentin discs according to manufacturers' guidance. The bonded specimen were prepared for shear bond strength test and sectioned occluso-gingivally into two slabs for scanning electron microscopy (SEM) observation.</p><p><b>RESULTS</b>The bonding strength between resin and enamel in B group [(29.38 ± 6.28) MPa] was higher than that in D group [(27.25 ± 7.03) MPa], and both of them were significantly higher than those in A [(22.92 ± 7.13) MPa] and C group [(10.92 ± 3.41) MPa] (P < 0.05). The highest dentin bonding strength was shown in B group [(27.28 ± 6.79) MPa], followed by A [(14.23 ± 6.39) MPa], D [(10.09 ± 3.26) MPa] and C group [(6.43 ± 1.60) MPa, P < 0.05].</p><p><b>CONCLUSIONS</b>The four resin cements have different enamel or dentin bonding properties.</p>

Measurement and comparison of the spectral transmittance of cerinate porcelain and human enamel / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To measure the spectral transmittance of Cerinate porcelain veneer and enamel in different color and different thickness.</p><p><b>METHODS</b>Samples of Cerinate porcelain veneers were prepared in different thickness (0.50 mm, 0.75 mm, 1.00 mm) and different Vita shade (A1, A2, A3). Enamel samples in shade A2 were made with three thickness (0.50 mm, 0.75 mm, 1.00 mm). A spectrophotometer with spectra range (380-800 nm) was employed to measure the spectral transmittance.</p><p><b>RESULTS</b>Spectral transmittance decreased with the increasing in the thickness of specimens and decreasing in the color darkness. The transmittance of Cerinate porcelain veneer material and enamel in the same color and same thickness hadn't significant difference.</p><p><b>CONCLUSION</b>The key factor to spectral transmittance of porcelain veneer materials is veneer's thickness, and the color of the materials has also some influence on it. Cerinate porcelain veneers can properly recover the transparency of teeth.</p>

Comparison of dentin nanoleakage among six adhesives / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the nanoleakage appearance in 6 dentin adhesives.</p><p><b>METHODS</b>Superficial occlusal dentin of 12 human molars without caries extracted freshly was exposed with 600-grit SiC papers under running water. Six adhesives were applied to dentin surfaces according to the manufacturers' instructions. The bonded teeth were sectioned occluso-gingivally into 0.9-mm-thick serial slabs that were stored in ammoniacal silver nitrate solution in the dark for 24 h and prepared for transmission electron microscope. The extent of nanoleakage among 6 dentin adhesives was measured and compared using one-way ANOVA.</p><p><b>RESULTS</b>The nanoleakage was observed obviously at the dentin-resin interfaces of all 6 adhesives. The average dentin nanoleakage values of Group A [BangDuo, (16.09 +/- 2.08)%], Group B [Single Bond, (13.39 +/- 1.81)%], and Group C [Prime&Bond NT, (11.27 +/- 1.94)%] were all significantly different (P < 0.05). There was no significant difference in the dentin nanoleakage between Group D [B(1), (12.13 +/- 2.11)%] and Group E [Clearfil SE Bond, (12.35 +/- 2.60)%], but both of them were lower than Group F [Adper Prompt, (14.93 +/- 2.67)%].</p><p><b>CONCLUSIONS</b>The nanoleakage phenomena at the dentin-resin interface were all observed diversely in the contemporary dental adhesives.</p>

Clinical evaluation of 546 tetracycline-stained teeth treated with Cerinate laminate veneers / 中华口腔医学杂志

<p><b>OBJECTIVE</b>The purpose of this study was to evaluate the clinical result of 546 tetracycline-stained teeth corrected with Cerinate porcelain laminate veneer system for esthetic purpose.</p><p><b>METHODS</b>546 tetracycline-stained teeth were corrected with Cerinate porcelain veneer system, and bonded with Ultra Bond resin cement. The restorations were recalled after 0.5 year, 1.5 years and 2.5 years, respectively. modified Ryge criteria were used to evaluate the veneers marginal adaptation, interfacial staining, secondary caries, postoperative sensitivity and the patients' satisfaction with the shade of the restorations.</p><p><b>RESULTS</b>this study found that 99% veneers had excellent marginal adaptations; and less than 1% veneers were rebonded after debond in the first half year application; the color of the veneers was stable and no evident staining was found. Almost all patients were satisfied with their restoration color after 1 year's application.</p><p><b>CONCLUSION</b>The research indicated that Cerinate porcelain veneer restoration system is a reliable and ideal choice for the correction of tetracycline-stained teeth.</p>