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Intramyocardial hydrogel injection is a promising therapy to prevent negative remodeling following myocardial infarction (MI). In this study, we report a mechanism for in-situ gel formation without external stimulation, resulting in an injectable and tissue-retainable hydrogel for MI treatment, and investigate its therapeutic outcomes. A liquid-like polymeric solution comprising poly(3-acrylamidophenylboronic acid- co -acrylamide) (BAAm), polyvinyl alcohol (PVA), and sorbitol (S) increases the viscous modulus by reducing the pre-added sorbitol concentration is developed. This solution achieves a sol-gel transition in-vitro in heart tissue by spontaneously diffusing the sorbitol. After intramyocardial injection, the BAAm/PVA/S with lower initial viscous modulus widely spreads in the myocardium and gelate compared to a viscoelastic alginate (ALG) hydrogel and is retained longer than the BAAm/S solution. Serial echocardiogram analyses prove that injecting the BAAm/PVA/S into the hearts of subacute MI rats significantly increases the fraction shortening and ejection shortening and attenuates the expansion of systolic LV diameter for up to 21 d after injection compared to the saline injection as a control, but the ALG injection does not. In addition, histological evaluation shows that only the BAAm/PVA/S decreases the infarct size and increases the wall thickness 21 d after injection. The BAAm/PVA/S intramyocardial injection is better at restraining systolic ventricular dilatation and cardiac failure in the rat MI model than in the control groups. Our findings highlight an effective injectable hydrogel therapy for MI by optimizing injectability-dependent distribution and retention of injected material. In-situ gelling material is a promising strategy for intramyocardial hydrogel injection therapy for myocardial infarction (MI). Since the sol-gel transition of reported materials is driven by external stimulation such as temperature, pH, or ultraviolet, their application in vivo remains challenging. In this study, we first reported a synthetic in-situ gelling material (BAAm/PVA/S) whose gelation is stimulated by spontaneously reducing pre-added sorbitol after contacting the heart tissue. The BAAm/PVA/S solution spreads evenly, and is retained for at least 21 d in the heart tissue. Our study demonstrated that intramyocardial injection of the BAAm/PVA/S with more extensive distribution and longer retention had better effects on preventing LV dilation and improving cardiac function after MI than that of viscoelastic ALG and saline solution. We expect that these findings provide fundamental information for the optimum design of injectable biomaterials for treating MI. [Display omitted] [ABSTRACT FROM AUTHOR]

Decellularized vessels (DVs) have the potential to serve as available grafts for small-diameter vascular (<6 mm) reconstruction. However, the absence of functional endothelia makes them likely to trigger platelet aggregation and thrombosis. Luminal surface modification is an efficient approach to prevent thrombosis and promote endothelialization. Previously, we identified a hemocompatible peptide, HGGVRLY, that showed endothelial affinity and antiplatelet ability. By conjugating HGGVRLY with a phenylazide group, we generated a photoreactive peptide that can be modified onto multiple materials, including non-denatured extracellular matrices. To preserve the natural collagen of DVs as much as possible, we used a lower ultrahydrostatic pressure than that previously reported to prepare decellularized grafts. The photoreactive HGGVRLY peptide could be modified onto DV grafts via UV exposure for only 2 min. Modified DVs showed improved endothelial affinity and antiplatelet ability in vitro. When rat abdominal aortas were replaced with DVs, modified DVs with more natural collagen demonstrated the highest patent rate after 10 weeks. Moreover, the photoreactive peptide remained on the lumen surface of DVs over two months after implantation. Therefore, the photoreactive peptide could be efficiently and sustainably modified onto DVs with more natural collagens, resulting in improved hemocompatibility. We employed a relatively lower ultrahydrostatic pressure to prepare decellularized vessels (DVs) with less denatured collagens to provide a more favorable environment for cell migration and proliferation. The hemocompatibility of DV luminal surface can be enhanced by peptide modification, but undenatured collagens are difficult to modify. We innovatively introduce a phenylazide group into the hemocompatible peptide HGGVRLY, which we previously identified to possess endothelial affinity and antiplatelet ability, to generate a photoreactive peptide. The photoreactive peptide can be efficiently and stably modified onto DVs with more natural collagens. DV grafts modified with photoreactive peptide exhibit enhanced in vivo patency. Furthermore, the sustainability of photoreactive peptide modification on DV grafts within bloodstream is evident after two months of transplantation. [Display omitted] [ABSTRACT FROM AUTHOR]

Thalidomide, an angiogenesis inhibitor, has recently been used to treat malignant canine tumors. This study retrospectively investigated the adverse events (AEs) of thalidomide administered to tumor-bearing dogs. We investigated the pharmacokinetics of thalidomide after administration and the rate of body weight change before and after administration. The initial thalidomide dose was 5 mg/kg per os once daily, which was increased to 10 mg/kg once daily in dogs with no significant AEs. Pharmacokinetics were measured in four dogs after the 5 mg/kg or 10 mg/kg dose. We evaluated AEs related to clinical signs in 51 patients; 9/51 had lethargy, 6/51 had tremor, 4/51 had dizziness, 31/51 had decreased appetite, 8/51 had vomiting, and 16/49 had soft stool/diarrhea. We evaluated hematologic toxicity in 44 patients with grade 3 or higher adverse events; 1/44 had thrombocytopenia, 1/44 had increased blood urea nitrogen concentrations, and 5/44 had increased alanine aminotransferase activities. The mean thalidomide blood levels were Cmax=1.4 ± 0.7 μg/mL (Area under the curve [AUC]0–24=8.5 ± 4.7 μg•hr /mL) and Cmax=3.2 ± 2.1 μg/ mL (AUC0–24=22.0 ± 14.7 μg•hr/mL) in the 5 mg/kg and 10 mg/kg groups, respectively. The Cmax and AUC in the 10 mg/kg group were comparable to the effective blood concentrations seen in humans administered thalidomide. The weight fluctuation rates were assessed in 24 dogs approximately 1 month after the start of thalidomide administration; more than half showed weight maintenance or gain. Most AEs were clinically acceptable; however, peripheral nerve signs were seen in some dogs. [ABSTRACT FROM AUTHOR]

Retroperitoneal hemangiosarcoma (RPHSA) is a rare tumor in dogs with a poorly understood prognosis after surgery. The objectives of this study were to investigate the clinical features and prognosis of canine RPHSA that had undergone surgical resection. In this single-center, retrospective cohort study, we reviewed the medical records of dogs that had undergone surgical resection for retroperitoneal tumors and received a histopathologic diagnosis of HSA between 2005 and 2021. The median progression-free survival (PFS) and overall survival (OS) were 77.5 days and 168 days, respectively. In the present study, canine RPHSA had an aggressive biological behavior similar to visceral HSA. Further studies in larger canine populations are needed to evaluate the efficacy of adjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to clarify the effect of occlusal force on appropriate optical interocclusal registration in clinical practice, considering periodontal ligament and jawbone deformation. Methods: Forty participants with natural, healthy dentition were enrolled (19 men and 21 women; mean age, 27.7 ± 2.0 years). A TRIOS3 intraoral scanner was used to scan the right lateral first premolar to the second molar areas of the upper and lower jaws. During scanning for interocclusal registration, participants were instructed to "bite normally," "bite lightly," and "bite strongly" to obtain data for the three occlusal patterns. The standard triangulated language (STL) data for each occlusion condition were superimposed using the appropriate software, following which the tooth displacement was calculated. The conventional method was also used to record the occlusal contact area for a silicone model using a dental contact analyzer. Results: Tooth displacement was significantly lower for the strong-bite condition than for the weak-bite condition (0.018 mm vs. 0.028 mm, P<0.05). As the occlusal force increased, the occlusal contact area also increased, and significant differences were observed among the different occlusal conditions (P<0.05). Conclusions: Occlusal contact area changed depending on the bite force when using the silicone impression or optical intraoral scanning methods. Moreover, using optical impression methods in "strong bite force" may reduce the deviation and allow for stable interocclusal registration. [ABSTRACT FROM AUTHOR]

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Three patients, aged 2 years 0 months, 2 years 2 months, and 6 years 1 month at the time of plain old balloon angioplasty (POBA), developed an aneurysm in the left anterior descending coronary branch after suffering from Kawasaki disease. POBA was subsequently performed due to 99 % stenosis proximal to the aneurysm. There was no restenosis within a few years after percutaneous coronary intervention, and there was no evidence of ischemia, although 75 % restenosis occurred in two patients after 7 years. Although calcified lesions are more likely to occur 6 years after the onset of Kawasaki disease, none of the patients in this study had calcified lesions within 4 years of Kawasaki disease onset, and good results were obtained with POBA alone. POBA can be safely performed in children and is an effective treatment for improving myocardial ischemia if calcification has not progressed. Plain old balloon angioplasty (POBA) can be performed effectively and safely for Kawasaki disease coronary artery stenosis in early childhood if calcification is minimal, with little restenosis for at least several years. POBA is a useful tool in the treatment of coronary artery stenosis in early childhood. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the relationship between the bond strength of stainless steel with two types of resin cements (MMA- and composite-based) on bovine enamel depending on the directionality of the applied force. The specimens were either placed in water or subjected to thermal cycles (TC), and the shear or tensile bond strengths (SBS or TBS) were determined. The SBS showed significantly greater than the TBS for both types of cement, and the SBS and TBS for composite-based cement had larger than MMA-based one. No significant difference in SBS was observed in the cements even after being subjected to TC. Cohesive failures of the cement and bovine enamel in the composite-based group, while adhesive failures were observed in MMA-based one. Consequently, the direction of the force at both cements affected the retention of stainless steel, and MMA-based cement was preferred when prioritizing less enamel damages. [ABSTRACT FROM AUTHOR]

The recent literature on maxillary implant overdenture (IOD) was reviewed in order to clarify its predictability and establish treatment guidelines. Electronic searches were performed using PubMed, and articles about maxillary IOD written after 1990 were reviewed, focusing on the following items: I. implant survival rate, II. maxillary IOD survival rate, III. number of implants, IV. attachment type, V. follow-up period, VI. implant system, and VII. opposing dentition. The review revealed an implant survival rate of 61-100% and an overdenture survival rate of 72.4-100%. The attachments used included bars, balls, locators, and telescope crowns. The minimum and maximum observation periods were 12 months and 120 months, respectively, and the number of implants used for supporting IOD ranged from 2 to 8. At present, there is no strong evidence to indicate that maxillary IOD is clearly superior for all the items examined. However, the existing data indicate that maxillary IOD has almost the same therapeutic effect as fixed implant superstructures, and is a treatment option that can be actively adopted for patients in whom fixed superstructures cannot be applied for various reasons. [ABSTRACT FROM AUTHOR]

Background: This study was performed to evaluate the impact of upgrade of radiotherapy system, including launch of intensity-modulated radiation therapy (IMRT), on the therapeutic outcomes. Materials and methods: Patients with head and neck (H&N) squamous cell carcinoma (SCC) who underwent postoperative radiotherapy at our hospital between June 2009 and July 2019 were retrospectively reviewed. In July 2014, we converted the radiotherapy technique for these patients from a 3-dimensional conformal radiotherapy (3D-CRT) to IMRT, along with the adoption of a meticulous planning policy and a few advanced procedures, including online imaging guidance. Results: A total of 136 patients (57 treated with the previous system and 79 treated with the upgraded system) were reviewed. There were significantly more patients with extracapsular extension in the upgraded-system group than the previous-system group (p = 0.0021). There were significantly fewer patients with ≥ Grade 2 acute and late adverse events in the upgraded-system group than the previous-system group. The differences in progression-free survival (PFS), distant metastasis-free survival (DFFS), locoregional progression-free survival (LRPFS), and overall survival (OS) between the two groups were not statistically significant (p = 0.8962, 0.9926, 0.6244, and 0.4827, respectively). Multivariate analysis revealed that the upgrade had neither positive nor negative impact on survival outcomes. Extracapsular extension was independently associated with decreased LRPFS and OS (p = 0.0499 and 0.0392, respectively). Conclusions: The IMRT-centered upgrade was beneficial for the postoperative patients with H&N SCC, because survival outcomes were sustained with less toxicities. [ABSTRACT FROM AUTHOR]

This narrative review aims to provide an overview of recent studies and case reports on three-dimensional (3D) printing, and to verify the applicability of 3D printers in the field of dental prostheses. This review was performed by conducting a search of PubMed. The clinical application of fabricating a prosthesis made with cobalt-chromium is considered possible depending on the material and hardware of the 3D printer. However, it is currently difficult to assess the clinical use of 3D-printed zirconia crowns. Further research is required, such as verification of materials used, margin morphology, and hardware. Clinically acceptable results have been reported for patterns using 3D printers. Interim restorations made using a 3D printer have been reported with good results that are considered clinically usable. Dentures made with 3D printers need further verification in terms of strength and deformation. Custom trays made with 3D printers are clinically useful, however, issues remain with design time and effort. Although several studies have reported the usefulness of 3D printers, further verification is required since 3D printers are still considered new technology. [ABSTRACT FROM AUTHOR]

Background: SGLT2i (sodium-glucose cotransporter 2 inhibitor), a class of anti-diabetic medications, is shown to reduce blood pressure (BP) in hypertensive patients with type 2 diabetes. Mechanisms underlying this action are unknown but SGLT2i-induced sympathoinhibition is thought to play a role. Whether SGLT2i reduces BP and sympathetic nerve activity (SNA) in a nondiabetic prehypertension model is unknown.Methods: Accordingly, we assessed changes in conscious BP using radiotelemetry and alterations in mean arterial pressure and renal SNA during simulated exercise in nondiabetic spontaneously hypertensive rats during chronic administration of a diet containing dapagliflozin (0.5 mg/kg per day) versus a control diet.Results: We found that dapagliflozin had no effect on fasting blood glucose, insulin, or hemoglobin A1C levels. However, dapagliflozin reduced BP in young (8-week old) spontaneously hypertensive rats as well as attenuated the age-related rise in BP in adult spontaneously hypertensive rat up to 17-weeks of age. The rises in mean arterial pressure and renal SNA during simulated exercise (exercise pressor reflex activation by hindlimb muscle contraction) were significantly reduced after 4 weeks of dapagliflozin (Δmean arterial pressure: 10±7 versus 25±14 mm Hg, Δrenal SNA: 31±17% versus 68±39%, P<0.05). Similarly, rises in mean arterial pressure and renal SNA during mechanoreflex stimulation by passive hindlimb stretching were also attenuated by dapagliflozin. Heart weight was significantly decreased in dapagliflozin compared with the control group.Conclusions: These data demonstrate a novel role for SGLT2i in reducing resting BP as well as the activity of skeletal muscle reflexes, independent of glycemic control. Our study may have important clinical implications for preventing hypertension and hypertensive heart disease in young prehypertensive individuals. [ABSTRACT FROM AUTHOR]

• Only 10.8% of healthcare providers (HCPs) who experienced work restriction were truly infected. • All infected HCPs restricted from working by symptom-based strategy. • There were no unexpectedly infected HCPs among those without work restriction. • Only 41.8% of HCPs with COVID-19-like symptoms restricted working. • Work restriction of HCPs with symptoms is the first step of infection prevention. Effectiveness of restricting healthcare providers (HCPs) from working based on the coronavirus disease 2019 (COVID-19)-like symptoms should be evaluated. A total of 495 HCPs in a tertiary care hospital in Tokyo, Japan, participated in this study between June and July in 2020. Analysis of serum anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody to identify infected HCPs, questionnaire surveys, and medical record reviews were conducted to evaluate the appropriateness of symptom-based work restriction for 10 days. Five participants (1.0%) were identified as infected. Forty-six participants (9.3%) experienced work restriction and all 5 infected participants (10.8%) restricted working, even though the real-time reverse transcription-polymerase chain reaction was positive only in 4 participants (80.0%). There were no unexpectedly infected participants among those who did not experience work restriction. However, only 46 of 110 HCPs with COVID-19-like symptoms (41.8%) restricted themselves from working. Symptom-based work restriction strategy successfully prevented infected HCPs to work, but showed low specificity to identify truly infected HCPs, and their low adherence to the strategy was revealed. HCPs with COVID-19-like symptoms should restrict working as the first step of infection prevention, but the strategy to identify truly infected HCPs is necessary. [ABSTRACT FROM AUTHOR]