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The use of dental resin composites adapted to computer-aided design/computer-aided manufacturing (CAD/CAM) processes for indirect tooth restoration has increased. A key factor for a successful tooth restoration is the bond between the CAD/CAM composite crown and abutment tooth, achieved using resin-based cement. However, the optimal pairing of the resin cement and CAD/CAM composites remains unclear. This study aimed to identify the optimal combination of a CAD/CAM composite and resin cement for bonding. A commercial methyl methacrylate (MMA)-based resin cement (Super-Bond (SB)) and four other composite-based resin cements (PANAVIA V5; PV, Multilink Automix (MA), ResiCem EX (RC), and RelyX Universal Resin Cement (RX)) were tested experimentally. For the CAD/CAM composites, a commercial polymer-infiltrated ceramic network (PICN)-based composite (VITA ENAMIC (VE)) and two dispersed filler (DF)-based composites (SHOFU BLOCK HC (SH) and CERASMART300 (CE)) were used. Each composite block underwent cutting, polishing, and alumina sandblasting. This was followed by characterization using scanning electron microscopy, inorganic content measurement, surface free energy (SFE) analysis, and shear bond strength (SBS) testing. The results demonstrated that the inorganic content and total SFE of the VE composite were the highest among the examined composites. Furthermore, it bonded highly effectively to all the resin cements. This indicated that PICN-based composites exhibit unique bonding features with resin cements. Additionally, the SBS test results indicated that MMA-based resin cement bonds effectively with both DF- and PICN-based composites. The combination of the PICN-based composite and MMA-based resin cement showed the best bonding performance. [ABSTRACT FROM AUTHOR]

Objectives Orthodontic mechanical force on the periodontal ligament induces extracellular adenosine triphosphate (ATP) release. However, mechanosensitive molecules have not been confirmed functionally in periodontal ligament cells. In the present study, we examined the roles of mechanosensitive PIEZO channels in the mechanically stimulated release of ATP in human periodontal ligament fibroblasts (HPdLFs). Materials and methods To examine PIEZO expression in HPdLFs, we performed reverse transcription–quantitative polymerase chain reaction, fluorescent immunostaining, and Ca2+ imaging. ATP concentrations were measured in culture medium after applications of the PIEZO1 agonist Yoda1 and compression force in a newly developed in vitro weight-loaded cell model (IVWLC) using balance weights and a 48-well plate. The mechanosensitive channel inhibitor GsMTx4 and the ATP-releasing route inhibitors clodronic acid, meclofenamic acid, and probenecid were used. To suppress PIEZO1 expression, short interference RNA (siRNA) treatment of the PIEZO1 gene was performed. Results PIEZO1 mRNA was expressed more abundantly than PIEZO2 mRNA in HPdLFs. HPdLF cell bodies were immunoreactive to anti-PIEZO1 antibody. Yoda1 increased intracellular Ca2+ and extracellular ATP concentrations in a dose-dependent manner. ATP release was inhibited by GsMTx4 and inhibitors of ATP release routes. In the IVWLC, HPdLFs released ATP in response to compression force but not in response to hypoxic stimulation that was simultaneously applied to cells. Mechanically stimulated ATP release was inhibited by GsMTx4, inhibitors of ATP-releasing routes and siRNA treatment of PIEZO1. Conclusions PIEZO1 on the cell membranes of HPdLFs is activated by compression force and then induces ATP release via intracellular Ca2+-dependent exocytosis and ATP-permeable channels. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons consisting of two or three rubicene substructures were designed as π‐conjugated compounds embedding five‐membered rings. The target compounds with t‐butyl groups were synthesized by the Scholl reaction of precursors consisting of 9,10‐diphenylanthracene units, even though a partially precyclized precursor was required for the synthesis of the trimer. These compounds were isolated as stable and dark blue solids. Single‐crystal X‐ray analysis and DFT calculations revealed the planar aromatic framework of these compounds. In the electronic spectra, the absorption and emission bands were considerably red‐shifted compared with those of the reference rubicene compound. In particular, the emission band of the trimer extended to the near‐IR region while retaining the emissive property. The narrowed HOMO‐LUMO gap with the extension of the π‐conjugation was confirmed by cyclic voltammetry and DFT calculations. [ABSTRACT FROM AUTHOR]

Stream habitat is distributed discontinuously, which restricts the dispersal of animals among streams. Freshwater decapod crustaceans have poor dispersal ability and thus may suffer high extinction risk in the face of habitat destruction and other forces. Here, the ecological characteristics of two freshwater decapods, the threatened crayfish Cambaroides japonicus (de Haan, 1841) and the widespread crab Geothelphusa dehaani (White, 1847), were compared. The objective of the study was to determine which characteristics are most likely to limit the distribution of C. japonicus.Environmental DNA sampling was conducted to detect C. japonicus and G. dehaani populations, and environmental characteristics were measured to identify suitable stream habitat. Phylogenetic divergence and genetic differentiation among populations were examined. Using species distribution modelling, the future distributions of both species under climate change were predicted.Stream habitats harbouring C. japonicus tended to be supplied with more beech leaves and fewer cedar leaves, whereas those of G. dehaani were relatively wide, indicating that C. japonicus favours upstream areas in natural broad‐leaved forest. The results also showed greater genetic divergence among populations of C. japonicus than those of G. dehaani. Modelling indicated that most areas within the current distribution of C. japonicus were predicted to be areas with low distribution probability under a future climate scenario.To protect C. japonicus, further loss of local populations should be prevented to allow for the maintenance of high genetic diversity among populations, which may provide the evolutionary capability of surviving under future climate conditions. To prevent further loss of C. japonicus populations, natural deciduous forests in mountainous areas need to be preserved. C. japonicus can be the indicator species within the freshwater environment in these forests. Conservation measures for C. japonicus should also be effective for the conservation of the other freshwater invertebrates in upstream areas. [ABSTRACT FROM AUTHOR]

Introduction: Knee osteoarthritis (KOA), the most common form of osteoarthritis (OA) is a considerable health concern worldwide. Platelet-rich plasma (PRP) is a common therapeutic option for KOA. Different types of PRPs have varying efficacies. However, a comparative analysis of the qualities of these PRPs is lacking. Methods: Two types of PRPs, including autologous protein solution (APS), and leukocyte-poor PRP (LP-PRP) along with whole blood (WB) and platelet-poor plasma (PPP) were characterized for platelet content, leukocyte content, and composition in 10 healthy volunteers (HV) (the controlled laboratory study) and 16 KOA patients (a retrospective observational study). Additionally, the levels of the platelet-derived growth factor (PDGF)-BB, and different cytokines were estimated in HV. Results: In HV, the concentrations of platelets and leukocytes, levels of different cytokines, including interleukin 1 receptor antagonist (IL-1Ra), soluble TNF receptor type II (sTNF-RII), and IL-1β, and the ratio of IL-1Ra/IL-1β were significantly higher in APS, whereas the PDGF-BB was higher in LP-PRP than APS. In KOA patients, a higher concentration of platelets was observed in LP-PRP, and a higher concentration of leukocytes was observed in APS than LP-PRP. Following the PAW classification system, LP-PRP was classified as P2-B type in HV (51.3 × 104/μl) and KOA (53.4 × 104/μl), whereas APS was classified as P3-A type in HV (110.1 × 104/μl) and P2-A type in KOA (29.0 × 104/μl). In a retrospective observational study, the KOA patients who underwent APS injection had a higher incidence of arthralgia, and this arthralgia lasted for a longer time than LP-PRP injection in the same individual. Discussion: The quality of the two PRPs differed distinctively depending on their preparation methods, which might affect their clinical efficacies and adverse events. Therefore, the characterization of these parameters should be prioritized while choosing PRP.

Poly-ether-ether-ketone (PEEK) is commonly employed in dental prostheses owing to its excellent mechanical properties; however, it is limited by its low bond strength with dental resin cement. This study aimed to clarify the type of resin cement most suitable for bonding to PEEK: methyl methacrylate (MMA)-based resin cement or composite-based resin cement. For this purpose, two MMA-based resin cements (Super-Bond EX and MULTIBOND II) and five composite-based resin cements (Block HC Cem, RelyX Universal Resin Cement, G-CEM LinkForce, Panavia V5, and Multilink Automix) were used in combination with appropriate adhesive primers. A PEEK block (SHOFU PEEK) was initially cut, polished, and sandblasted with alumina. The sandblasted PEEK was then bonded to resin cement with adhesive primer according to the manufacturer's instructions. The resulting specimens were immersed in water at 37 °C for 24 h, followed by thermocycling. Subsequently, the tensile bond strengths (TBSs) of the specimens were measured; the TBSs of the composite-based resin cements after thermocycling were found to be zero (G-CEM LinkForce, Panavia V5, and Multilink Automix), 0.03 ± 0.04 (RelyX Universal Resin Cement), or 1.6 ± 2.7 (Block HC Cem), whereas those of Super-Bond and MULTIBOND were 11.9 ± 2.6 and 4.8 ± 2.3 MPa, respectively. The results demonstrated that MMA-based resin cements exhibited stronger bonding to PEEK than composite-based resin cements. [ABSTRACT FROM AUTHOR]

A 44‐year‐old woman who was quarantined for 5 days after the diagnosis of coronavirus disease of 2019 (COVID‐19) was transferred to our hospital with the complaint of chest pain. The patient was unvaccinated. Electrocardiography revealed ST elevation in the lateral leads. Echocardiographic biventricular dysfunction with oedematous wall thickening was identified. Cardiac enzyme levels were elevated; however, C‐reactive protein (CRP) levels, and the coronary angiogram were normal. The patient required mechanical circulatory support to stabilize haemodynamics and was treated with remdesivir, baricitinib, and intravenous methylprednisolone. She recovered after 13 days of mechanical support. Serial cardiac magnetic resonance imaging revealed acute myocardial oedema and subsequent fibrosis. An endomyocardial biopsy on admission showed mild interstitial inflammatory infiltrates with endomyocardial fibrous thickening and mild interstitial fibrosis of the myocardium. Normal CRP levels suggested minor involvement of interleukin (IL)‐6, supporting the efficacy of baricitinib. [ABSTRACT FROM AUTHOR]

Background: The outbreak of the 2019 novel coronavirus disease (COVID-19) led to an enforced quarantine period and limited training and match activities for athletes. Purpose: To report the influence of the COVID-19 pandemic on the occurrence of injury in Japanese male professional soccer players. Study Design: Descriptive epidemiology study. Methods: In total, 21 clubs in the 2019 season and 28 clubs in the 2020 season from the Japan Professional Football League were prospectively followed, and 16 clubs in 2019 and 24 clubs in 2020 were analyzed in this study. Individual training, match exposure, and time-loss injuries were recorded using an electronic data capture system. The influence of COVID-19–related suspension during the 2020 season was retrospectively investigated via comparisons with the 2019 season. Results: Total activity time included 114,001 hours in training and 16,339 hours in matches in 2019 and 170,798 hours in training and 25,411 hours in matches in 2020. The mean training interruption period caused by COVID-19 in 2020 was 39.9 days (range, 3-65 days), and the mean game-interruption period was 70.1 days (range, 58-79 days). The total number of injuries was 1495 in 2019 and 1701 in 2020. The overall injury incidence per 1000 hours of exposure was 5.7 in 2019 and 5.8 in 2020. The overall injury burden per 1000 hours of exposure was 155.5 days in 2019 and 130.2 days in 2020. The muscle injury incidence was highest in May 2020, immediately after the suspension period. Conclusion: The overall injury incidence did not differ between 2019 and 2020. However, muscle injury incidence notably increased in the 2 months after the COVID-19 pandemic suspension period. [ABSTRACT FROM AUTHOR]