Weight loss and functional decline in older Japanese people: A cohort study using large-scale claims data

BACKGROUND

The association between weight loss and subsequent functional decline is uncertain. The study aims to elucidate the association between weight loss over a year and subsequent functional decline requiring assistance in performing their activities of daily living in older individuals.

METHODS

The study used data from the publicly funded Long-Term Care Insurance service in Japan, which provides coverage for long-term care services for individuals unable to perform activities of daily living due to physical or cognitive impairment. The study enrolled people born in or before 1949, who underwent health checkups in both 2014 and 2015. The participants were followed from 2015 to the worsening of functional decline requiring long-term care services, death, or February 28, 2019, whichever occurred first. The risk of subsequent functional decline in each weight loss category was estimated using a Cox regression model adjusted for age, sex, baseline body mass index, smoking, and Charlson comorbidity index.

RESULTS

We identified 67,452 eligible individuals from the database. The median follow-up period was 1,284 days. The hazard ratios (95 % confidence interval) of functional decline for -1 %, -2 %, -3 %, -4 %, and ≤-5% weight change compared to 0 % weight change were 1.17 (1.03-1.32), 1.26 (1.11-1.43), 1.29 (1.12-1.49), 1.61 (1.39-1.87), and 1.79 (1.58-1.99), respectively.

CONCLUSIONS AND IMPLICATIONS

Older people with weight loss of 1 % or more were at risk of functional decline. Close weight monitoring may serve as an easy and inexpensive means of identifying older individuals at risk of functional decline.

Inhibition of cysteine protease disturbs the topological relationship between bone resorption and formation in vitro

INTRODUCTION

Osteoporosis is a global health issue. Bisphosphonates that are commonly used to treat osteoporosis suppress both bone resorption and subsequent bone formation. Inhibition of cathepsin K, a cysteine proteinase secreted by osteoclasts, was reported to suppress bone resorption while preserving or increasing bone formation. Analyses of the different effects of antiresorptive reagents such as bisphosphonates and cysteine proteinase inhibitors will contribute to the understanding of the mechanisms underlying bone remodeling.

MATERIALS AND METHODS

Our team has developed an in vitro system in which bone remodeling can be temporally observed at the cellular level by 2-photon microscopy. We used this system in the present study to examine the effects of the cysteine proteinase inhibitor E-64 and those of zoledronic acid on bone remodeling.

RESULTS

In the control group, the amount of the reduction and the increase in the matrix were correlated in each region of interest, indicating the topological and quantitative coordination of bone resorption and formation. Parameters for osteoblasts, osteoclasts, and matrix resorption/formation were also correlated. E-64 disrupted the correlation between resorption and formation by potentially inhibiting the emergence of spherical osteoblasts, which are speculated to be reversal cells in the resorption sites.

CONCLUSION

These new findings help clarify coupling mechanisms and will contribute to the development of new drugs for osteoporosis.

Persistent magnetic coherence in magnets

When excited, the magnetization in a magnet precesses around the field in an anticlockwise manner on a timescale governed by viscous magnetization damping, after which any information carried by the initial actuation seems to be lost. This damping appears to be a fundamental bottleneck for the use of magnets in information processing. However, here we demonstrate the recall of the magnetization-precession phase after times that exceed the damping timescale by two orders of magnitude using dedicated two-colour microwave pump-probe experiments for a Y3Fe5O12 microstructured film. Time-resolved magnetization state tomography confirms the persistent magnetic coherence by revealing a double-exponential decay of magnetization correlation. We attribute persistent magnetic coherence to a feedback effect, that is, coherent coupling of the uniform precession with long-lived excitations at the minima of the spin-wave dispersion relation. Our finding liberates magnetic systems from the strong damping in nanostructures that has limited their use in coherent information storage and processing.

A clinical presentation of markerless augmented reality assisted surgery for resection of a dentigerous cyst in the maxillary sinus

Dentigerous cysts (DC) in the maxillary sinus are rare and pose challenges for effective treatment. Despite various available surgical techniques, a definitive approach remains debated. This study introduces a markerless Augmented Reality Assisted Surgery (ARAS) system that utilizes tooth image recognition and surgical simulation to enhance the precision of maxillary sinus DC extractions. Using advanced technology, such as 3-dimensional (3D) intraoral scanning and CT imaging for accurate data capture, the system aligns virtual models with patient anatomy without external markers, demonstrating a minimally invasive surgical solution. The ARAS system enabled precise surgical planning and realization of a DC extraction in the maxillary sinus by creating a bone window in direct contact with the cyst, assisting in complete removal with minimal risk to adjacent structures. The ARAS system may aid surgeons in visualizing patient anatomy during surgery, with overlays of relevant medical images, aiding in precise localization and minimizing tissue damage.

miR-92a-3p-inspired shRNA exhibits pro-chondrogenic and chondrocyte protective effects in osteoarthritis treatment through targeting SMAD6/7

INTRODUCTION

Osteoarthritis (OA) compromises patients' quality of life and requires further study. Although miR-92a-3p was reported to possess chondroprotective effects, the underlying mechanism requires further clarification. The objectives of this study were to elucidate the mechanism by which miR-92a-3p alleviates OA and to examine the efficacy of shRNA-92a-3p, which was designed based on mature miR-92a-3p.

MATERIALS AND METHODS

TargetScan and luciferase reporter assay were used to predict the target of miR-92a-3p. Adipose-derived stem cells (ADSCs) were transfected with miR-92a-3p/miR-NC mimic for the analysis of chondrogenic biomarkers and SMAD proteins. ADSCs and osteoarthritic chondrocytes were transduced with shRNA-92a-3p for the analysis of chondrogenic biomarkers and SMAD proteins. OA was surgically induced in C57BL/6JJcl mice, and ADSCs with/without shRNA-92a-3p transduction were intra-articularly injected for the assessment of cartilage damage.

RESULTS

SMAD6 and SMAD7 were predicted as direct targets of miR-92a-3p by TargetScan and luciferase reporter assay. Transfection of the miR-92a-3p mimic resulted in a decrease in SMAD6 and SMAD7 levels and an increase in phospho-SMAD2/3, phospho-SMAD1/5/9, SOX9, collagen type II, and aggrecan levels in ADSCs. Furthermore, shRNA-92a-3p decreased SMAD6 and SMAD7 levels, and increased phospho-SMAD2/3, phospho-SMAD1/5/9, SOX9, collagen type II, and aggrecan levels in ADSCs and osteoarthritic chondrocytes. Additionally, ADSC-shRNA-92a-3p-EVs reduced the rate of decrease of SOX9, collagen type II, and aggrecan in osteoarthritic chondrocytes. In mice with surgically induced OA, shRNA-92a-3p-treated ADSCs alleviated cartilage damage more effectively than nontreated ADSCs.

CONCLUSIONS

miR-92a-3p and shRNA-92a-3p exhibit therapeutic effects in treating OA by targeting SMAD6 and SMAD7, thereby enhancing TGF-β signaling.

Saturation of Percutaneous Oxygen Decreases with Meal Consumption in Patients with Acute Pneumonia

OBJECTIVE

This study aimed to investigate how respiratory status may be affected during meal consumption in patients with acute pneumonia, mainly aspiration pneumonia, using percutaneous oxygen saturation (SpO2) and pulse rate (PR) measurements.

METHODS

We recruited 44 inpatients at the Towada City Hospital and divided them into 'pneumonia' and 'control' groups. Generalized linear mixed effects model was used for analysis. The pneumonia group comprised 22 patients (mean age 81.2 ± 7.0 years, body mass index [BMI] 21.1 ± 4.0 kg/m2) with 1-3 points A-DROP scores. The control group comprised 22 patients (mean age 80.5 ± 4.9 years, BMI 20.9 ± 2.9 kg/m2) with no obvious respiratory diseases. SpO2 and PR were measured 30 min before, during, and 30 min after meals.

RESULTS

SpO2 was significantly lower during meals in the pneumonia group (-1.60%; 95% confidence interval = -2.76 to -0.44). There were no significant changes in PR during or after meals in the pneumonia group.

CONCLUSIONS

This study suggests pneumonia may worsen respiratory status during meal intake. Patients with pneumonia may be unable to eat adequately due to worsened oxygenation during meals, even in the absence of aspiration. Therefore, it is important to observe whether there is a decrease in respiratory status during meals.

Lipoaspirate stored at a constant low temperature by electric control suppresses intracellular metabolism and maintains high cell viability

Background

Cell therapy is a useful treatment method for wide spectrum of diseases which utilizes the immunosuppressive and regenerative abilities of administered cells. It is essential to build a transport system of tissues from which cells are harvested, because various external factors, such as temperature, time, air pressure, and vibration affect the cell functions isolated from body tissues. In particular, temperature is a critical factor which determines the viability of the cells and organs. In this study, we investigated the optimal temperature during the transportation of lipoaspirates from which adipose -derived stem cells (ASCs) were isolated.

Method

Lipoaspirates obtained by liposuctions (lipomatic or vaser method) were transported in four different temperature zones (4, 20, 32, and 37 °C) in a transport container which is electrically controlled to maintain a constant temperature during transport. Stromal vascular fractions (SVFs) were harvested from the lipoaspirate, and the cell number, viability and proliferation rate and the yield of ASCs were examined. In addition, the metabolic state of the cells was examined.

Results

ASCs from lipoaspirates transported at high temperature significantly decreased cell viability, while those at low temperature maintained high cell viability and showed good cell proliferation. In addition, transportation of lipoaspirates at low temperature resulted in a high level of NAD+/NADH, coenzymes involved in intracellular metabolism, and a low level of lactate in lipoaspirate suppressed the glycolytic system of intracellular metabolism, in ASCs.

Conclusion

The lipoaspirate transported at 4 °C exhibited best results regarding live cell number, viability and cell proliferation in our experiments. This study offers a direction to build a transport system that connects laboratories and hospitals and achieve a beneficial therapy for patients.

Subcutaneously Transplanted Fresh Cartilage in Allogeneic and Xenogeneic Immunocompetent Mouse

Cartilage is considered to be immune privileged in general. Clinically, live cells are removed from subcutaneously transplanted allogeneic cartilage mainly for preservation and for infection control. However, because maintaining cartilage feature requires live chondrocyte, it would be beneficial to subcutaneously transplant cartilage with live chondrocyte even if it was allogeneic. We harvested femoral head from 3-week-old male C57BL/6 mice, subcutaneously transplanted to 6-week-old male mice, BALB/c, BALB/c nu/nu, or C57BL/6-Tg (enhanced green fluorescent protein [EGFP] under the control of the CMV-IE enhancer, chicken beta-actin promoter, rabbit beta-globin genomic DNA [CAG promoter]), as allogeneic, allogeneic immunodeficient control, or syngeneic transplantation. We also transplanted cartilaginous particles from human induced pluripotent stem cells derived from human leukocyte antigen homozygous donor to 6-week-old male mice either BALB/c and BALB/c nu/nu as xenogeneic or xenogeneic immunodeficient control. The transplantation periods were 1, 2, 3, 4, 8, 12, and 24 weeks. As the result, we did not observe exposure of the transplant or apparent macroscopic inflammatory in all samples. Histological analysis suggested that the femoral head showed focal ossification and thinning in syngeneic transplantation. In allogeneic transplantation, slight invasion of CD3 (+) T cell and the denaturation of the cartilage were observed, suggesting immune reaction against allogeneic cartilage. In xenogeneic transplantation, slight invasion of CD3 (+) cell and CD4 (+) cell and the structure of the perichondrium-like tissue got unclear, suggesting slight immune reaction against xenogeneic cartilage. Our findings suggest that we should carefully investigate for appropriate procedure to control immune reaction against allogeneic cartilage with live chondrocyte and to maintain its cartilage feature for long time.

Involvement of Impaired Angiogenesis and Myelosuppression in Antiresorptive-agent Related Osteonecrosis of the Jaw Mouse Model

OBJECTIVE

To explore the involvement of bone marrow cells and angiogenesis in the pathogenesis of antiresorptive agent-related osteonecrosis of the jaw (ARONJ).

METHODS

We performed micro-computed tomography (CT) and histological analyses in an ARONJ mouse model generated using bisphosphonate (BP) and cyclophosphamide (CY).

RESULTS

Micro-CT analysis showed that BP and CY inhibited osteoneogenesis in the extraction socket. Histological analysis at 3 days after tooth extraction showed inhibition of vascular endothelial cell and mesenchymal stem cell mobilization into the extraction socket. When neovascularization of the extraction fossa was observed from as early as 1 day after extraction, it occurred predominantly in the area adjacent to the extraction fossa and close to the bone marrow cavity. In addition, the extraction fossa communicated with the adjacent bone marrow via the vasculature. Histological evaluation of the alveolar bone marrow around the extraction socket showed a decrease in bone marrow cells in the BP + CY group.

CONCLUSION

Both inhibition of angiogenesis and suppression of bone marrow cell mobilization are involved in the pathogenesis of ARONJ.

Abstract 6005: Promoter methylation occurs at high frequencies regardless of mutation status of tumor-associated genes in oral malignancies

Background: Genetic and epigenetic alterations are both important in tumorigenesis. However, their association in oral carcinogenesis has not been fully investigated yet. In this study, we analyzed somatic mutations of tumor-related genes and promoter methylation of tumor-suppressor genes (TSGs) in oral malignancies/premalignancies, and analyzed their association.

Materials and Methods: 39 oral squamous cell carcinomas (OSCCs) and 2 oral epithelial dysplasias (OEDs) were obtained as fresh-frozen?. Somatic mutations of 46 tumor-related genes, 13 TSGs and 33 oncogenes, were analyzed by targeted next-generation sequencing (NGS). Promoter methylation of five TSG: (p16/INK4A, CMTM3, EGFLAM, NKX2-3, and RBP4) were determined by methylation-specific PCR (MSP).

Results: Somatic mutations of tumor-related genes were observed in 63.4% of 41 OSCCs/OEDs. Particularly, mutations of p53 and PIK3CA were observed 39.0% and 31.7%, respectively, of the 41 OSCCs/OEDs. Promoter methylation of p16/INK4A, CMTM3, NKX2-3, RBP4, and EGFLAM were observed in 34.1%, 48.8%, 41.5%, 68.3%, and 36.6%, respectively, of the 41 OSCCs/OEDs. No differences in the frequency of promoter methylation of the five genes were observed between tumors with and without somatic mutations of p53 and PIK3CA.

Conclusions: Promoter methylation was observed at high frequencies regardless of mutation status of p53 and PIK3CA in OSCCs/OEDs. Oral tumorigenesis appears to be difficult to be explained solely by genetic events indicating involvement of epigenetic events.

Citation Format: Masanobu Abe, Kazuto Hoshi, Toshikazu Ushijima. Promoter methylation occurs at high frequencies regardless of mutation status of tumor-associated genes in oral malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6005.

A Comparative Study of Periodontal Health Status between International and Domestic University Students in Japan

BACKGROUND

In our previous study, international university students showed a significantly higher dental caries morbidity rate than domestic students. On the other hand, the periodontal health status of international university students has not been clarified yet. In this study, we compared the periodontal health status of international and domestic university students in Japan.

METHODS

We conducted a retrospective review of the clinical data of the university students that visited a dental clinic in the division for health service promotion at a university in Tokyo for screening between April 2017 and March 2019. Bleeding on probing (BOP), calculus deposition and probing pocket depth (PPD) were investigated.

RESULTS

The records of 231 university students (79 international and 152 domestic university students) were analyzed; 84.8% of international students were from Asian countries (n = 67). The international university students showed a higher percentage of BOP than domestic students (49.4% and 34.2%, respectively: p < 0.05) and they showed more extensive calculus deposition (calculus grading score [CGS]) than domestic university students (1.68 and 1.43, respectively: p < 0.01), despite no significant difference in PPD.

CONCLUSIONS

The current study shows that international university students have poorer periodontal health than domestic students in Japan, even though the result might include many uncertainties and possible biases. To prevent severe periodontitis in the future, regular checkups and thorough oral health care are essential for the university students, especially those from foreign countries.

Risk of post-extraction bleeding with direct oral anticoagulant compared with warfarin: Retrospective cohort study using large scale claims data in Japan

INTRODUCTION

Comparative safety of direct oral anticoagulants vs. warfarin in patients undergoing tooth extraction remains unclear. We compared the incidence of post-extraction bleeding between patients taking warfarin and those taking direct oral anticoagulants (DOACs) using administrative claims data.

MATERIALS AND METHODS

We identified outpatients on anticoagulant therapy who underwent permanent tooth extraction between 2015 and 2020 and categorized them into the warfarin and DOAC groups based on medication prescribed within six months prior to tooth extraction. We used the overlap propensity score weighting method to balance the baseline characteristics between the groups and compared the incidence of post-extraction bleeding within seven days after tooth extraction.

RESULTS

Among 5253 eligible patients, those in the DOAC group (n = 3696) were older and less frequently prescribed antiplatelets than those in the warfarin group (n = 1557). The distribution of tooth extraction type and number of teeth extracted in a single procedure did not differ between the groups. The unadjusted incidences of post-extraction bleeding in the warfarin and DOAC groups were 35 (2.2 %) and 71 (1.9 %), respectively. Moreover, the overlap weighting analysis showed that the adjusted odds ratio of post-extraction bleeding in the DOAC group in comparison with that in the warfarin group was 0.84 (95 % confidence interval, 0.54-1.31).

CONCLUSION

The incidence of post-extraction bleeding in patients taking DOACs was comparable to that in patients taking warfarin. The findings suggest that dentists and physicians should exercise the same degree of caution when extracting teeth in patients on DOACs and those on warfarin in terms of post-extraction bleeding.

Computer-Assisted Preoperative Simulation and Augmented Reality for Extraction of Impacted Supernumerary Teeth: A Clinical Case Report of Two Cases

Delayed eruption, malocclusion, poor oral hygiene, and formation of follicular cysts are some complications associated with an impacted supernumerary tooth (ST). Although surgical extraction is one of the methods to prevent these complications, it can also lead to fractured roots or has a risk of permanent injury to young teeth and gingiva. Recently, computer-assisted preoperative simulation has been helpful in planning the surgery for precise extraction of impacted ST guided with 3-dimensional images. Herein, we present 2 cases of extraction of severely impacted ST guided by preoperative computer-assisted simulation and intraoperative augmented reality. While being minimally invasive, the augmented reality-guided system can precisely highlight the tooth position. The therapeutic aspects of these procedures have also been discussed.

Quantitative analyses of matrices, osteoblasts, and osteoclasts during bone remodeling using an in vitro system

INTRODUCTION

Bone remodeling plays a central role in the maintenance of bone homeostasis. Our group has established an in vitro system by which the cellular events during bone remodeling can be observed longitudinally. This study used this system to quantitatively analyze osteoblasts, osteoclasts, and matrices to elucidate their temporal changes and correlations.

MATERIALS AND METHODS

Osteoblasts from EGFP mice were cultured to form calcified nodules, followed by co-culture with bone marrow macrophages from Tnfrsf11a^Cre/+ x Ai14 mice for 3 weeks (resorption phase). Then cells were cultured with osteoblast differentiation medium for 3 weeks (formation phase). The same sites were observed weekly using 2-photon microscopy. Matrices were detected using second harmonic generation. Parameters related to matrices, osteoblasts, and osteoclasts were quantified and statistically analyzed.

RESULTS

Resorption and replenishment of the matrix were observed at the same sites by 2 photon microscopy. Gross quantification revealed that matrix and osteoblast parameters decreased in the resorption phase and increased in the formation phase, while osteoclast parameters showed the opposite pattern. When one field of view was divided into 16 regions of interest (ROIs) and correlations between parameters were analyzed in each ROI, decreased and increased matrix volumes were moderately correlated. Parameters of matrices and osteoblasts, and those of matrices and osteoclasts exhibited moderate correlations, while those of osteoblasts and osteoclasts were only weakly correlated.

CONCLUSION

Several correlations between cells and matrix during remodeling were demonstrated quantitatively. This system may be a powerful tool for the research of bone remodeling.

Effect of conventional treatment on dental complications and ectopic ossifications among 30 adults with XLH

CONTEXT

Conventional treatment of XLH was reported to prevent dental complications, but whether the preventive effect was different among different types of teeth, including anterior teeth and molar teeth, is uncertain. Evidence of the preventive effect of conventional treatment on ectopic ossifications is also limited.

OBJECTIVE

To compare dental complications and ectopic ossifications among XLH adults with early (< 5 years old) or late (≥5 years old) conventional treatment.

METHODS

This retrospective observational study included a total of 30 adults with XLH using orthopantomograms, spinal computed tomography scans and X-rays of hip/knee joints. Dental complications, including decayed, missing filled (DMF) index and devitalized tooth, apical periodontitis, and periodontitis, were evaluated. The index of ossification of the anterior/posterior longitudinal ligament and yellow ligament (OA/OP/OY index) and the sum of the OA/OP/OY index (OS index) were utilized to evaluate the severity of spinal ligament ossification. The severity of the hip/knee osteophytes was evaluated by the Kellgren-Lawrence (KL) classification.

RESULTS

The number of sound teeth was significantly lower, and the DMF index was significantly higher in patients with late treatment. The severity of dental complications in the anterior tooth and molar tooth, OA/OP/OY/OS index, and KL grade were not significantly different among patients with early treatment and those with late treatment.

CONCLUSION

Early treatment could prevent dental complications but did not prevent ectopic ossification in adult patients with XLH. The difference in the preventive effect was not observed among different types of teeth.

Utility of Multimodality Approach Including Systemic FGF23 Venous Sampling in Localizing Phosphaturic Mesenchymal Tumors

Context

Tumor-induced osteomalacia (TIO) is one of the most common forms of acquired fibroblast growth factor 23 (FGF23)-related hypophosphatemia and is usually caused by phosphaturic mesenchymal tumors (PMTs). Although the complete resection of PMTs can cure TIO, preoperative localization of tumors by standard imaging modalities is often challenging. In addition to ¹⁸F-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography (FDG-PET) and ¹¹¹In-pentetreotide scintigraphy (SRS), systemic FGF23 venous sampling (FGF23VS) has been used to help localize PMTs in specialized institutions.

Objective

This study aimed to evaluate the diagnostic performance of each imaging test and their combinations in localizing PMTs.

Methods

In an observational retrospective study of patients with adult-onset FGF23-related osteomalacia who underwent all 3 imaging studies (FDG-PET, SRS, and FGF23VS), the rate of successful preoperative localization of the tumors was evaluated only in the patients with pathological diagnoses of PMTs, considering the possibility that pathogenesis of patients without identified tumors might be due to other causes such as late-onset hereditary FGF23-related hypophosphatemia.

Results

A total of 30 Japanese patients with TIO (median age, 60 years [range, 28-87 years]; 10 women [33.3%]) were included in the study. The success rate of preoperative localization for each test and combinations of 2 or 3 tests among 18 patients with PMTs was as follows: 72% (FDG-PET), 72% (SRS), 94% (FGF23VS), 89% (FDG-PET, SRS), 100% (FDG-PET, FGF23VS), 94% (SRS, FGF23VS), and 100% (FDG-PET, SRS, and FGF23VS).

Conclusion

We observed the highest localization rate of PMTs in patients with identified PMTs with the combination of FDG-PET and FGF23VS.

Spatiotemporal Analysis of Osteoblast Morphology and Wnt Signal‐Induced Osteoblast Reactivation during Bone Modeling in Vitro

Bone nodule formation by differentiating osteoblasts is considered an in vitro model that mimics bone modeling. However, the details of osteoblast behavior and matrix production during bone nodule formation are poorly understood. Here, we present a spatiotemporal analysis system for evaluating osteoblast morphology and matrix production during bone modeling in vitro via two-photon microscopy. Using this system, a change in osteoblast morphology from cuboidal to flat was observed during the formation of mineralized nodules, and this change was quantified. Areas with high bone formation were densely populated with cuboidal osteoblasts, which were characterized by blebs, protruding structures on their cell membranes. Cuboidal osteoblasts with blebs were highly mobile, and osteoblast blebs exhibited a polar distribution. Furthermore, mimicking romosozumab treatment, when differentiated flattened osteoblasts were stimulated with BIO, a GSK3β inhibitor, they were reactivated to acquire a cuboidal morphology with blebs on their membranes and produced more matrix than nonstimulated cells. Our analysis system is a powerful tool for evaluating the cell morphology and function of osteoblasts during bone modeling. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Clinical findings of triglyceride deposit cardiomyovasculopathy

Background

Triglyceride (TG) deposit cardiomyovasculopathy (TGCV) is a novel cardiovascular disorder and was recently encoded as an orphan disease in Europe (ORPHA code: 565612). Defective intracellular lipolysis results in TG accumulation in the myocardium and coronary arteries in TGCV. The myocardial washout rate (WR) of iodine-123-β-methyl-p-iodophenylpentadecanoic acid (BMIPP) is an essential indicator to evaluate myocardial lipolysis in vivo, and decreased WR (&lt;10%) of BMIPP is one of the essential items of diagnostic criteria for TGCV.

Purpose

To clarify clinical findings of TGCV including comorbid conditions and laboratory findings.

Methods

We enrolled 234 patients who underwent BMIPP scintigraphy between September 2015 and July 2019. The distributions of TGCV in each comorbidity, cardiac functions and laboratory findings were investigated.

Results

In total, 104 patients were diagnosed with definitive TGCV. The BMIPP WR of TGCV patients was −1.37±10.6%. TGCV patients had various comorbid conditions, including coronary artery disease (75%), diabetes mellitus (56%), and heart failure (21%). Left ventricular ejection fraction (LVEF) of TGCV patients was significantly lower than that of non-TGCV patients (38.1±18.0% vs. 43.6±18.9%, p-value=0.026). Moreover, among those who did not take lipid-lowering drugs, there was no difference in the serum TG level between TGCV and non-TGCV patients (TGCV: n=44, 127±84.6 mg/dL, non-TGCV: n=66, 133±70.7 mg/dL, p-value=0.73).

Conclusions

TGCV patients showed multiple coexistence of coronary artery disease, diabetes mellitus, or heart failure with lower LVEF. Serum TG level was not significantly different between TGCV and non-TGCV patients. Serum TG did not affect the intracellular TG accumulation in TGCV patients directly, and this result was consistent with the pathophysiological hypothesis that the TG accumulation in the myocardial cytoplasm is due to intracellular lipase dysfunction.

Funding Acknowledgement

Type of funding sources: None.

Complete Lateral Positioning Enabled Feeding in a Patient with Aspiration Pneumonia

The complete lateral position can be used to widen the lateral pharynx in a direction that facilitates swallowing and reduces the risk of aspiration, even if the patient is unable to eat in the sitting position. Here, we report a case of aspiration pneumonia in a patient who was unable to eat in the sitting position after swallowing endoscopy, but was able to eat in the complete lateral position. By employing complete lateral positioning, more patients may be able to continue oral intake.

Long-term dental outcomes in patients with fibrodysplasia ossificans progressiva: a report of three cases of tooth extraction

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare autosomal dominant disorder characterized by congenital skeletal malformation and progressive heterotopic ossification. In the oral and maxillofacial region, deformity of the temporomandibular joint is a common feature of FOP, as well as restricted mouth opening derived from heterotopic ossification in the masticatory muscles. Since surgical procedures are generally not recommended because of the risk of flare-ups and increased heterotopic ossification, reports of tooth extractions and their outcomes in patients with FOP are limited. The present article reports the long-term oral outcomes of three Japanese patients with FOP, in whom the teeth were deliberately extracted to avoid the risk of oral inflammation causing further heterotopic ossification. The extractions were conducted under local or general anesthesia, and healing of sockets was nonproblematic with the formation of new bone. Undesirable events, including progression of heterotopic ossification in the oral and maxillofacial region and further restriction of mouth opening, were not apparent. The extractions also alleviated the existing inflammation, contributing to maintaining their oral hygiene. These cases suggest that deliberate planning and judicious surgery could induce favorable healing after tooth extractions in patients with FOP, leading to long-term stability of their oral health status.

Hematopoietic-Mesenchymal Signals Regulate the Properties of Mesenchymal Stem Cells

It is well known that the properties of hematopoietic stem/progenitor cells (HSCs), such as their self-renewal ability and multipotency, are maintained through interactions with mesenchymal stem/stromal cells (MSCs). MSCs are rare cells that are present in the bone marrow and are useful for clinical applications due to their functional ability. To obtain the necessary number of cells, MSCs must be cultured to expand, but this causes a remarkable decrease in stem cell properties, such as multipotency and proliferation ability. In this study, we show that the c-Mpl signal, which is related to the maintenance of hematopoietic stem cells, has an important effect on the proliferation and differentiation ability of MSCs. Utilizing a co-culture system comprising MSCs and HSCs, it is suggested that signaling from hematopoietic cells to MSCs supports cell proliferation. Interestingly, the enhanced proliferation ability of the HSCs was decreased in c-Mpl knock-out HSCs (c-Mpl-KO). In addition, the MSCs co-cultured with c-Mpl-KO HSCs had reduced MSC marker expression (PDGFRa and Sca-1) compared to the MSCs co-cultured with c-Mpl-wild-type HSCs. These results suggest that a hematopoietic–mesenchymal signal exists, and that the state of the HSCs is important for the stability of MSC properties.

Systemic Disorders Closely Associated with Malocclusion in Late Adolescence: A Review and Perspective

Oral diseases such as dental caries and periodontal disease are reported to be associated with various systemic diseases such as heart disease, respiratory disease, diabetes, rheumatism, and metabolic syndrome, thus increasing the importance of prevention and early treatment [...].

Superior stemness of a rapidly growing subgroup of isolated human auricular chondrocytes and the potential for use in cartilage regenerative therapy

Introduction

In cartilage regenerative medicine, transplanted chondrocytes contain a mixture of populations, that complicates the regeneration of uniform cartilage tissue. Our group previously reported that chondrocytes with higher chondrogenic ability could be enriched by selection of rapidly growing cells. In this study, the detailed properties of rapidly growing chondrocytes were examined and compared to slowly growing cells.

Methods

Human auricular chondrocytes were fluorescently labeled with carboxyfluorescein succinimidyl ester (CFSE) and analyzed using flow cytometry, focusing on division rates as indicated by fluorescence intensity and cell morphology according to the forward scatter and side scatter. Rapid and slow growing cell groups were harvested on days 2 and 4 after CFSE labeling, and their ability to produce cartilage matrix in vitro was examined. To compare the chondrogenic ability in vivo, the cells were seeded on poly-l-lactic acid scaffolds and transplanted into nude mice. Gene expression differences between the rapid and slow cell groups were investigated by microarray analysis.

Results

On day 2 after CFSE labeling, the rapidly growing cell group showed the highest proliferation rate. The results of pellet culture showed that the rapid cell group produced more glycosaminoglycans per cell than the slow cell group. The amount of glycosaminoglycan production was highest in the rapid cell group on day 2 after CFSE labeling, indicating high chondrogenic ability. Furthermore, microarray, gene ontology, and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed upregulation of genes that promote cell division such as origin recognition complex subunit 1 and downregulation of genes that inhibit cell division such as cyclin dependent kinase inhibitor 1A. Besides cell cycle-related genes, chondrocyte-related genes such as serpin family B member 2, clusterin, bone morphogenetic protein 2, and matrix metalloproteinase 3 were downregulated, while fibroblast growth factor 5 which is involved in stem cell maintenance, and coiled-coil and C2 domain containing 2A, which is required for cilia formation, were upregulated.

Conclusion

The results showed that the rapid cell group proliferated well and had more undifferentiated properties, suggesting a higher stemness. The present findings provide a basis for the use of the rapid cell group in cartilage regeneration.

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Highly-chondrogenic chondrocytes can be enriched based on their high division rate.

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Rapidly dividing cells are smaller and have less granularity.

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Cell cycle-related genes are upregulated in rapidly dividing cells.

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Chondrocyte-related genes are downregulated in rapidly dividing cells.

Hematopoietic progenitor cells specifically induce a unique immune response in dental pulp under conditions of systemic inflammation

Teeth are exposed to various stimuli, including bacterial, thermal, and physical stimuli. Therefore, immune cells present in the normal dental pulp and the immune response to these stimuli have been studied. However, the relationship between systemic inflammation, such as that induced by viral infection, and changes occurring in dental pulp is not well known. This study aimed to investigate the immunological and hematological responses to systemic inflammation in dental pulp. Poly(I:C), a toll-like receptor 3 agonist, was injected into mice every two days to simulate a systemic inflammatory state in which type I interferon (IFN–I) was produced. The untreated normal state was defined as a steady state, and the states of acute and chronic inflammation were defined according to the period of administration. Changes in the abundance and dynamics of hematopoietic and immune cells in dental pulp, bone marrow and peripheral blood were quantitatively investigated in the steady state and under conditions of inflammation induced by IFN-l. We found that dental pulp in the steady state contained only a few hematopoietic cells, but a greater variety of immune cells than previously reported. B cells were also found in the steady state. An increase in multipotent progenitor cell levels was observed in the dental pulp during both acute and chronic inflammation. The increased multipotent progenitor cells in the dental pulp during acute inflammation tended to differentiate into the myeloid lineage. On the other hand, there was an influx of B cells into the dental pulp during chronic inflammation. These results revealed that a unique immune response is induced in the dental pulp by systemic inflammation, which would lead to a significant change in the perspective of dentists on the utility of dental pulp in the management of systemic diseases.

Requirement of direct contact between chondrocytes and macrophages for the maturation of regenerative cartilage

Regenerative cartilage prepared from cultured chondrocytes is generally immature in vitro and matures after transplantation. Although many factors, including host cells and humoral factors, have been shown to affect cartilage maturation in vivo, the requirement of direct cell-cell contact between host and donor cells remains to be verified. In this study, we examined the host cells that promote cartilage maturation via cell-cell contact. Based on analysis of the transplanted chondrocytes, we examined the contribution of endothelial cells and macrophages. Using a semiclosed device that is permeable to tissue fluids while blocking host cells, we selectively transplanted chondrocytes and HUVECs or untreated/M1-polarized/M2-polarized RAW264.7 cells. As a result, untreated RAW264.7 cells induced cartilage regeneration. Furthermore, an in vitro coculture assay indicated communication between chondrocytes and RAW264.7 cells mediated by RNA, suggesting the involvement of extracellular vesicles in this process. These findings provide insights for establishing a method of in vitro cartilage regeneration.

M1-like macrophage contributes to chondrogenesis in vitro

Cartilage tissues have poor self-repairing abilities. Regenerative medicine can be applied to recover cartilage tissue damage in the oral and maxillofacial regions. However, hitherto it has not been possible to predict the maturity of the tissue construction after transplantation or to prepare mature cartilage tissues before transplantation that can meet clinical needs. Macrophages play an important role in cartilage tissue regeneration, although the exact mechanisms remain unknown. In this study, we established and verified an in vitro experimental system for the direct co-culture of cell pellets prepared from mouse auricular chondrocytes and macrophages polarized into four phenotypes (M1-like, M1, M2-like, and M2). We demonstrate that cartilage pellets co-cultured with M1-like promoted collagen type 2 and aggrecan production and induced the most significant increase in chondrogenesis. Furthermore, M1-like shifted to M2 on day 7 of co-culture, suggesting that the cartilage pellet supplied factors that changed the polarization of M1-like. Our findings suggest that cartilage regenerative medicine will be most effective if the maturation of cartilage tissues is induced in vitro by co-culture with M1-like before transplantation.

Implications for clinical dental practice during the coronavirus disease pandemic: A scoping review

PURPOSE

It is over a year since the first case of coronavirus disease (COVID-19) was confirmed in China. This paper reviews and summarizes the characteristics of COVID-19, as understood of December 2020, from a dental perspective.

STUDY SELECTION

The PubMed and Scopus online databases were searched using a combination of free words and Medical Subject Headings terms: "dentist" OR "oral care" AND "COVID-19" OR "SARS-CoV-2."

RESULTS

Older people and those with underlying medical conditions have an increased risk of serious illness due to COVID-19. The virus enters the body by binding to the angiotensin-converting enzyme 2 (ACE2) receptor. It is common for people with COVID-19 to have mild or no symptoms. Moreover, the disease is not contagious in most infected people; it is only highly contagious in some infected people, thereby forming clusters. Due to the large number of virus particles that are shed prior to the onset of symptoms of the disease, retrospective surveys are important. Appropriate personal protective equipment against corona vortices is also important in clinical practice. Although polymerase chain reaction tests are useful for confirming infection in suspected individuals, their reliability is questionable. In addition, concerns regarding long-term sequelae have been reported.

CONCLUSIONS

There are few high-quality reports on the implications of COVID-19 in dental practice. However, reports suggest that insufficient oral hygiene may be a risk factor for infection. Reports that ACE2 receptors are abundant in the oral cavity also suggest the importance of oral care.

Validity of diagnoses and procedures in Japanese dental claims data

BACKGROUND

Dental claims data have been used for epidemiological studies without establishing the validity of the recorded diagnoses or procedures. The present study aimed to examine the accuracy of diagnoses, procedures, operation time, and the number of teeth recorded in dental claims data.

METHODS

We reviewed the charts of 200 patients who visited and 100 patients who were hospitalized in the Department of General Dentistry, Orthodontics, and Oral and Maxillofacial Surgery in an academic hospital between August 2012 and December 2017. The sensitivity and specificity of the dental claims data for five diseases and 15 procedures were evaluated. We assessed the difference in the number of teeth and duration of general anesthesia between claims data and chart reviews.

RESULTS

Sensitivity was more than 86% for six out of seven diagnoses except for pericoronitis (67%). Specificity ranged from 72% (periodontal disease) to 100% (oral cancer for inpatient). The sensitivity of procedures ranged from 10% (scaling for inpatient) to 100%, and the specificity ranged from 6% (food intake on the day of the surgery) to 100%. The mean (standard deviation [SD]) number of teeth in the chart review was 22.6 (6.8), and in the dental claims was 21.6 (8.6). The mean (SD) operation time was 171.2 (120.3) minutes, while the duration of general anesthesia was 270.9 (171.3) minutes.

CONCLUSIONS

The present study is the first study to validate dental claims data, and indicates the extent of usefulness of each diagnosis and procedure for future dental research using administrative data.

Different phenotypes and chondrogenic responses of human menstrual blood and bone marrow mesenchymal stem cells to activin A and TGF-β3

BACKGROUND

Due to its low capacity for self-repair, articular cartilage is highly susceptible to damage and deterioration, which leads to the development of degenerative joint diseases such as osteoarthritis (OA). Menstrual blood-derived mesenchymal stem/stromal cells (MenSCs) are much less characterized, as compared to bone marrow mesenchymal stem/stromal cells (BMMSCs). However, MenSCs seem an attractive alternative to classical BMMSCs due to ease of access and broader differentiation capacity. The aim of this study was to evaluate chondrogenic differentiation potential of MenSCs and BMMSCs stimulated with transforming growth factor β (TGF-β3) and activin A.

METHODS

MenSCs (n = 6) and BMMSCs (n = 5) were isolated from different healthy donors. Expression of cell surface markers CD90, CD73, CD105, CD44, CD45, CD14, CD36, CD55, CD54, CD63, CD106, CD34, CD10, and Notch1 was analyzed by flow cytometry. Cell proliferation capacity was determined using CCK-8 proliferation kit and cell migration ability was evaluated by scratch assay. Adipogenic differentiation capacity was evaluated according to Oil-Red staining and osteogenic differentiation according to Alizarin Red staining. Chondrogenic differentiation (activin A and TGF-β3 stimulation) was investigated in vitro and in vivo (subcutaneous scaffolds in nude BALB/c mice) by expression of chondrogenic genes (collagen type II, aggrecan), GAG assay and histologically. Activin A protein production was evaluated by ELISA during chondrogenic differentiation in monolayer culture.

RESULTS

MenSCs exhibited a higher proliferation rate, as compared to BMMSCs, and a different expression profile of several cell surface markers. Activin A stimulated collagen type II gene expression and glycosaminoglycan synthesis in TGF-β3 treated MenSCs but not in BMMSCs, both in vitro and in vivo, although the effects of TGF-β3 alone were more pronounced in BMMSCs in vitro.

CONCLUSION

These data suggest that activin A exerts differential effects on the induction of chondrogenic differentiation in MenSCs vs. BMMSCs, which implies that different mechanisms of chondrogenic regulation are activated in these cells. Following further optimization of differentiation protocols and the choice of growth factors, potentially including activin A, MenSCs may turn out to be a promising population of stem cells for the development of cell-based therapies with the capacity to stimulate cartilage repair and regeneration in OA and related osteoarticular disorders.

Histochemical and Morphometrical Analyses of Scarless Wound Healing in Mouse Fetal Model

OBJECTIVE

Scar formation is an inevitable outcome after craniofacial surgery in the congenital facial anomaly. Scarless healing is the ultimate treatment after the surgery. Therefore, we elucidate the mechanism underlying scarless healing during fetal development.

METHODS

A full-thickness back skin excision (1 × 0.5 mm) was made at embryonic day 16.5 (E16.5) and 18.5 (E18.5) in fetal C57BL/6J mice and examined the histochemical and morphometrical findings of wound healing after 48 hours.

RESULTS

The wound made at E16.5 showed almost complete re-epithelialization with fine reticular dermal collagen fibers, but not at E18.5. The ratio of CK5 positive area was significantly higher in the wound of E16.5 operation than in the E18.5. The wounds made at E18.5 showed granulation tissue formation which will lead to subsequent scar formation. The collagen fibers tended to be thinner in wound than in normal skin, while the decrease in the number of fibers but the increase in the straightness of fibers were evident in the wound at E18.5.

CONCLUSION

Transition point of scarless healing seemed between E16.5 and E18.5 in mice, which may imply that the potential of epithelial regeneration and matrix formation was changed, possibly due to alteration of cell constitution and decrease in stemness, at that time.

Novel operative technique of advancement urethral meatoplasty utilizing buccal mucosa for Vulvar Paget's disease with urethral invasion: two case reports

BACKGROUND

Vulvar Paget's disease (VPD) is a rare malignant disorder originating in the external genitalia. It occasionally invades into urethral or vaginal mucosa of female, making surgical treatment more complicating. In case of urethral invasion of Paget's cells, systematic mapping biopsy of urethral mucosa is the standard of care to determine the range of surgical resection. Resection of urethral mucosa and simple skin grafting often result in urethral stricture after surgery, which severely deteriorates patient's quality of life.

CASE PRESENTATION

We applied a new technique of advancement urethral meatoplasty using buccal mucosa, in two Japanese cases of VPD with urethral invasion. After broad resection of vulvar skin together with the urethral mucosa, buccal mucosa was implanted between advanced urethral mucosa and skin graft. In both cases, we could prevent urethral stricture one year and two years after surgery, respectively.

CONCLUSION

This technique prevented urethral stricture after surgery and could be a useful technique as part of urethroplasty for VPD.

Establishment of a new technique for the fabrication of regenerative cartilage with a microslicer device to prepare three dimensional diced cartilage

Chondrocytes are utilized to cartilage regeneration by being harvested through enzymatic digestion and expanded by monolayer culture. However, these procedures will cause deterioration and dedifferentiation of the chondrocytes. In addition, scaffolds are often needed to provide the cartilage with mechanical strength and three-dimensional structures. We tried to use diced cartilage prepared using a micro-slicer without digestion, monolayer culture or scaffolds. In this study, an appropriate culture condition to induce the fusion of diced cartilage in vitro and cartilage regeneration in vitro and in vivo was determined to realize a scaffold-free cartilage regeneration. As a result, diced cartilages aggregated when they were cultured more than 5 weeks in the media containing 10% fetal bovine serum (FBS). Diced cartilage cultured for 7 weeks with the media containing 10%, followed by the culture with the media containing insulin-like growth factor-1 for 5 weeks in the ultralow attachment plate showed most prominent cartilage formation both in vitro and in vivo. The volume of regenerated cartilage was 2.14 times larger than that of the original cartilage. These results indicated that large regenerative cartilage from a small amount of cartilage was achieved without deterioration or dedifferentiation.

The usefulness of the decellularized matrix from three-dimensional regenerative cartilage as a scaffold material

In cartilage tissue engineering, research on materials for three-dimensional (3D) scaffold has attracted attention. Decellularized matrix can be one of the candidates for the scaffold material. In this study, decellularization of regenerated cartilage was carried out and its effectiveness as a scaffold material was examined. Three-dimensionally-cultured cartilage constructs in the differentiation medium containing IGF-1 produced more cartilage matrix than those in the proliferation medium. Detergent-enzymatic method (DEM) could decellularize 3D-cultured cartilage constructs only by 1 cycle without breaking down the structure of the constructs. In vitro, newly-seeded chondrocytes were infiltrated and engrafted into decellularized constructs in the proliferation medium, and newly formed fibers were observed around the surface where newly-seeded cells were attached. Recellularized constructs could mature similarly as those without decellularization in vivo. The decellularized 3D-cultured matrix from regenerative cartilage is expected to be used as a scaffold material in the future.

Ear Cartilage Reconstruction Combining Induced Pluripotent Stem Cell-Derived Cartilage and Three-Dimensional Shape-Memory Scaffold

Microtia is a congenital malformation of the auricle. The conventional therapy for microtia is reconstruction of the auricle by using the patient's own costal cartilage. Because it is invasive to harvest costal cartilages, less invasive ways for auricular reconstruction need to be established. Recent reports have indicated a new method for the production of cartilaginous particles from human induced pluripotent stem cells. To adopt this method to create an auricular-shaped regenerative cartilage, a novel scaffold with the property of a three-dimensional shape memory was created. A scaffold with a three-dimensional shape of auricular frames composed of a helix and an antihelix, which was designed to mimic an auricular framework carved from autologous costal cartilage and transplanted in auricular reconstruction, was prepared, filled with cartilaginous particles, and subcutaneously transplanted in nude rats. The auricular-shaped regenerative cartilage maintained the given shape and cartilage features in vivo for 1 year. Our findings suggest a novel approach for auricular reconstruction.

Swallowing evaluation by the Kuchikara Taberu Balance Chart and videoendscopic examination reveals that respiratory conditions, chewing, and position are strongly related to dysphagia

This study focused on the Kuchikara Taberu Balance Chart (KTBC) as a tool for swallowing function evaluation. To clarify the relationship between videoendoscopic (VE) examination of swallowing function and the KTBC, we compared median KTBC scores with and without laryngeal penetration identified by VE. Sixty-five patients with a mean age of 84.3 ± 7.9 years were examined at the Towada City Hospital. The patients were classified into groups based on laryngeal penetration, including 28 patients with and 37 patients without penetration. We found no significant differences in patient backgrounds. The median KTBC score (interquartile range) was 36.5 (31-44.5) in the group with laryngeal penetration and 42 (35-48.5) in the group without penetration, but the scores were not significantly different (level of statistical significance at α = 0.0036 determined by the Bonferroni correction method) when compared with the Mann-Whitney U test (36.5 vs. 42, z = -2.33, p = 0.020). The median respiratory condition (3 vs. 4, z = - 3.23; p < 0.0036), oral preparatory and propulsive phases (3 vs. 4, z = - 2.96; p < 0.0036), and position and endurance (1 vs. 3, z = - 3.25; p < 0.0036) scores were significantly lower in the group with laryngeal penetration. This study revealed a correlation between laryngeal penetration confirmed by VE and KTBC scores. Consequently, respiratory condition, oral preparatory and propulsive phases, and position and endurance may be useful as tools for the assessment of swallowing. In particular, we recommend adding respiratory status to dysphagia screening.

Awareness of Malocclusion Is Closely Associated with Allergic Rhinitis, Asthma, and Arrhythmia in Late Adolescents

Background: Oral infectious diseases are typified by dental caries and periodontal diseases and are known to be associated with various systemic diseases. However, clear associations between occlusal disorders and systemic diseases have not yet been established. We investigated the association between an awareness of malocclusion and common diseases in late adolescence. Methods: We retrospectively reviewed the data of mandatory medical questionnaires that are a legal requirement of the freshman medical checkup. We collected the data of all the students who completed the questionnaires between April 2017 and 2019. The data were analyzed using the χ² test and multivariate analysis was performed with a binomial logistic regression model. Results: The subjects were 9098 students aged 17–19 (mean age 18.3 years). The rate of awareness of malocclusion was 2.14% (195 out of 9098 eligible subjects; 160 males and 35 females). These students had significantly greater rates of allergic rhinitis, asthma, and arrhythmia (p < 0.001). Multivariate analysis revealed significant rates of allergic rhinitis (odds ratio [OR] 2.184, 95% confidence interval [CI]: 1.468–3.250, p < 0.001), asthma (OR 1.843, 95%CI: 1.153–2.945, p = 0.011), and arrhythmia (OR 2.809, 95%CI: 1.083–7.288, p = 0.034) among students with an awareness of malocclusion. Conclusion: We identified close associations between an awareness of malocclusion and systemic diseases including allergic rhinitis, asthma, and arrhythmia in the late adolescent population. These results reinforce the associations between malocclusion and allergic rhinitis and asthma, as well as providing novel insight into the association of malocclusion and arrhythmia. However, further research is necessary to confirm the associations and explore the mechanisms underlying these associations.

Photosensitizer With Illumination Enhances In Vivo Antitumor Effect of Anti-ROBO1 Immunotoxin on Maxillary Sinus Squamous Cell Carcinoma

BACKGROUND/AIM

Head and neck squamous cell carcinoma (HNSCC) is one of the most common types of cancer worldwide. Our study focused on the axon guidance receptor roundabout guidance receptor 1 (ROBO1) as a target for monoclonal antibody therapy of HNSCC. We previously showed that saporin-conjugated anti-ROBO1 (B5209B) immunotoxin (IT-ROBO1) enhanced cytotoxic effects on HNSCC cells in combination with the photosensitizer aluminum phthalocyanine disulphonate (AlPcS2a) and illumination. We examined the effects of this combination therapy in a mouse xenograft model.

MATERIALS AND METHODS

IT-ROBO1 was intraperitoneally administered to HSQ-89 (derived from Japanese maxillary sinus squamous carcinoma, RCB0789; RIKEN, Tsukuba, Japan) xenografted mice. After 3 days, AlPcS2a was injected subcutaneously around the tumor and the area was illuminated at 650 nm for 30 min. The growth of the tumor was evaluated and the effects on the tumor were examined.

RESULTS

Pronounced anti-tumor effects were elicited by the administration of IT-ROBO1 and AlPcS2a with light illumination on tumor size and pathological characteristics.

CONCLUSION

The results showed that photosensitizer treatment with illumination robustly enhanced the antitumor effect of the IT-ROBO1 immunotoxin.

Close Associations of Gum Bleeding with Systemic Diseases in Late Adolescence

BACKGROUND

Though it is well known that periodontal diseases are associated with various systemic diseases in adults, the associations in late adolescents have not been adequately elucidated. We investigated the association between gum bleeding (a major symptom of periodontal diseases) and common systemic diseases in late adolescents: allergic, respiratory, and otorhinolaryngologic diseases.

METHODS

We conducted a retrospective review of the mandatory medical questionnaires administered as a part of legally required freshman medical checkup between April 2017 and April 2019 at the University of Tokyo. Among the total of 9376 sets of responses, 9098 sets from students aged less than 20 were analyzed. An χ2 test and univariate and multivariate binomial logistic regression analyses were performed using SAS ver. 9.4. A value of p < 0.05 was accepted as significant.

RESULTS

According to the questionnaire data, 3321 students (36.5%; 2780 males and 541 females) responded that they experienced gum bleeding whenever they brushed their teeth. These students had significantly higher incidence rates of otitis media/externa and asthma/cough-variant asthma (p = 0.001 and p = 0.006, respectively). The results of the multivariate analysis showed significant rates of the following complications among these students: (1) otitis media/externa (odds ratio (OR) 1.691; 95% confidence interval (CI): 1.193-2.396; p = 0.003), (2) asthma/cough-variant asthma (OR 1.303; 95% CI: 1.091-1.556; p = 0.003), and (3) male gender (OR 1.536; 95% CI: 1.337-1.765; p < 0.001).

CONCLUSIONS

Gum bleeding was closely associated with otitis media/externa and asthma in late adolescents. Our study reinforces new evidence about the association between periodontal diseases and asthma, and it reveals a novel and close association between gum bleeding and otitis media/externa.

Adipose-derived stem cells improve tendon repair and prevent ectopic ossification in tendinopathy by inhibiting inflammation and inducing neovascularization in the early stage of tendon healing

INTRODUCTION

Achilles tendinopathy is characterized by scar formation or ectopic ossification, both of which result in pain and worsened physical function in athletes and older people. Although cell therapy using adipose-derived stem cells (ASCs) has been shown to be effective for tendinopathy, the underlying mechanisms by which ASCs result in tendon healing in vivo have not yet been fully clarified.

METHODS

ASCs were obtained from the fat pads of EGFP transgenic mice by collagenase digestion. C57BL/6 mice were used in a collagenase-induced injury model. ASCs were transplanted into injury sites at 1 week after injury. Tendons were harvested at 9 days, 2 weeks, and 4 weeks after transplantation, and analyzed by histological examination and μCT scanning.

RESULTS

Histological analysis and μCT scanning revealed greater recovery of collagen fibers and suppression of ectopic ossification in the ASC-treated group than in the control group at 2 and 4 weeks after injury. Immunohistochemical analysis identified transplanted ASCs in the tendon core close to peritenon and connective tissue at 2 days and 1 week after transplantation, but not at 3 weeks. Furthermore, while the expression levels of IL-1β, GLUT1, and CA9 were significantly reduced in the ASC group compared to the control group at 9 days after injury, those of VEGF and the number of CD31 positive vessels were significantly increased.

CONCLUSION

The efficacy of ASCs for tendon repair and the prevention of ectopic ossification in Achilles tendinopathy were demonstrated. Our data suggest that ASCs can modulate inflammation and induce neovascularization in the early stage of tendon injury.

Optimization of culture duration of bone marrow cells before transplantation with a β-tricalcium phosphate/recombinant collagen peptide hybrid scaffold

INTRODUCTION

Currently, various kinds of materials are used for the treatment of bone defects. In general, these materials have a problem of formativeness. The three -dimensional (3D) printing technique has been introduced to fabricate artificial bone with arbitrary shapes, but poor bone replacement is still problematic.Our group has created a β⁻tricalcium phosphate (β⁻TCP) scaffold by applying 3D printing technology. This scaffold has an arbitrary shape and an internal structure suitable for cell loading, growth, and colonization. The scaffold was coated with a recombinant collagen peptide (RCP) to promote bone replacement.As indicated by several studies, cells loaded to scaffolds promote bone regeneration, especially when they are induced osteoblastic differentiation before transplantation. In this study, culture duration for bone marrow cells was optimized before being loaded to this new scaffold material.

METHOD

Bone marrow cells isolated from C57BL/6J mice were subjected to osteogenic culture for 4, 7, and 14 days. The differentiation status of the cells was examined by alkaline phosphatase staining, alizarin red staining, and real-time RT-PCR for differentiation markers. In addition, the flow of changes in the abundance of endothelial cells and monocytes was analyzed by flow cytometry according to the culture period of bone marrow cells.Next, cells at days 4, 7, and 14 of culture were placed on a β-TCP/RCP scaffold and implanted subcutaneously into the back of C57BL/6J mice. Grafts were harvested and evaluated histologically 8 weeks later. Finally, Cells cultured for 7 days were also transplanted subperiosteally in the skull of the mouse with scaffolds.

RESULT

Alkaline phosphatase staining was most prominent at 7 days, and alizarin red staining was positive at 14 days. Real-time RT-PCR revealed that Runx2 and Alp peaked at 7 days, while expression of Col1a1 and Bglap was highest at 14 days. Flow cytometry indicated that endothelial cells increased from day 0 to day 7, while monocytes increased continuously from day 0 to day 14. When transplanted into mice, the scaffold with cells cultured for 7 days exhibited the most prominent osteogenesis. The scaffold, which was transplanted subperiosteally in the skull, retained its shape and was replaced with regenerated bone over a large area of the field of view.

CONCLUSION

Osteoblasts before full maturation are most efficient for bone regeneration, and the pre-culture period suitable for cells to be loaded onto a β-TCP/RCP hybrid scaffold is approximately 7 days.This β-TCP/RCP hybrid scaffolds will also be useful for bone augmentation.

Controlling gene activation by enhancers through a drug-inducible topological insulator

While regulation of gene-enhancer interaction is intensively studied, its application remains limited. Here, we reconstituted arrays of CTCF-binding sites and devised a synthetic topological insulator with tetO for chromatin-engineering (STITCH). By coupling STITCH with tetR linked to the KRAB domain to induce heterochromatin and disable the insulation, we developed a drug-inducible system to control gene activation by enhancers. In human induced pluripotent stem cells, STITCH inserted between MYC and the enhancer down-regulated MYC. Progressive mutagenesis of STITCH led to a preferential escalation of the gene-enhancer interaction, corroborating the strong insulation ability of STITCH. STITCH also altered epigenetic states around MYC. Time-course analysis by drug induction uncovered deposition and removal of H3K27me3 repressive marks follows and reflects, but does not precede and determine, the expression change. Finally, STITCH inserted near NEUROG2 impaired the gene activation in differentiating neural progenitor cells. Thus, STITCH should be broadly useful for functional genetic studies.

Controlling the Phenotype of Macrophages Promotes Maturation of Tissue-Engineered Cartilage

Tissue reactions after transplantation can affect the maturation and prognosis of the transplanted engineered tissue in regenerative medicine. Since macrophages are broadly subdivided into two major phenotypes, inflammatory (M1) and anti-inflammatory/wound healing (M2), in this study, we examined the properties of macrophages in transplantation of tissue-engineered cartilage, to clarify their effects on cartilage maturation. Human chondrocytes were embedded in a poly-L-lactic acid scaffold, which was transplanted subcutaneously on the back in athymic mice. When the constructs were analyzed by real-time polymerase chain reaction, interleukin 1 expression was detectable at 4 days, and it reached a peak at 7 days. Interleukin 6 expression was increased at 7 to 11 days, suggesting that M1 macrophages were abundant around this time. On the other hand, expression of markers for M2 macrophages occurred rather later, with Fizz and Ym1 expression peaking at around 11 to 14 days, possibly indicating that polarization of macrophages in tissue-engineered cartilage could shift from M1 to M2 around 11 days after transplantation. When cultured by using the conditioned medium of M2 macrophages, chondrocytes showed significantly increased expression of type 2 collagen, suggesting that M2 macrophages could enhance the maturation of tissue-engineered cartilage. Also, by partially depleting macrophages with clodronate liposomes in the initial period, during which M1 macrophages were dominant, more cartilage matrix accumulated in transplanted constructs at 2 weeks. It was suggested that polarization of macrophages shifted from M1 to M2 in the transplantation of tissue-engineered cartilage, and controlling the polarization could be advantageous for the maturation of transplanted engineered tissues. Impact statement In transplantation of engineered tissues, it is imperative for immune reactions to proceed in a proper and timely manner. In this study, we transplanted tissue-engineered cartilage consisting of a biodegradable polymer scaffold and chondrocytes, and examined the properties of macrophages. It was shown that the polarization of macrophages shifted from inflammatory (M1) to anti-inflammatory/wound healing (M2) around 11 days after transplantation. Partial suppression of macrophages at the early stage of transplantation, which were mainly M1 macrophages, promoted more accumulation of cartilage matrix. This study indicates a possible approach to facilitate cartilage maturation by intervening in the polarity of macrophages.

Glial Fibrillary Acidic Protein as Biomarker Indicates Purity and Property of Auricular Chondrocytes

Instead of the silicone implants previously used for repair and reconstruction of the auricle and nose lost due to accidents and disease, a new treatment method using tissue-engineered cartilage has been attracting attention. The quality of cultured cells is important in this method because it affects treatment outcomes. However, a marker of chondrocytes, particularly auricular chondrocytes, has not yet been established. The objective of this study was to establish an optimal marker to evaluate the quality of cultured auricular chondrocytes as a cell source of regenerative cartilage tissue. Gene expression levels were comprehensively compared using the microarray method between human undifferentiated and dedifferentiated auricular chondrocytes to investigate a candidate quality control index with an expression level that is high in differentiated cells, but markedly decreases in dedifferentiated cells. We identified glial fibrillary acidic protein (GFAP) as a marker that decreased with serial passages in auricular chondrocytes. GFAP was not detected in articular chondrocytes, costal chondrocytes, or fibroblasts, which need to be distinguished from auricular chondrocytes in cell cultures. GFAP mRNA expression was observed in cultured auricular chondrocytes, and GFAP protein levels were also measured in the cell lysates and culture supernatants of these cells. However, GFAP levels detected from mRNA and protein in cell lysates were significantly decreased by increases in the incubation period. In contrast, the amount of protein in the cell supernatant was not affected by the incubation period. Furthermore, the protein level of GFAP in the supernatants of cultured cells correlated with the in vitro and in vivo production of the cartilage matrix by these cells. The productivity of the cartilage matrix in cultured auricular chondrocytes may be predicted by measuring GFAP protein levels in the culture supernatants of these cells. Thus, GFAP is regarded as a marker of the purity and properties of cultured auricular chondrocytes.

Influence of Damage-Associated Molecular Patterns from Chondrocytes in Tissue-Engineered Cartilage

To obtain stable outcomes in regenerative medicine, the quality of cells for transplantation is of great importance. Cellular stress potentially results in the release of damage-associated molecular patterns (DAMPs) and activates immunological responses, affecting the outcome of transplanted tissue. In this study, we intentionally prepared necrotic chondrocytes that would gradually die and release DAMPs and investigated how the maturation of tissue-engineered cartilage was affected. Necrotic chondrocytes were prepared by a conventional heat-treatment method, by which their viability started to decrease after 24 h. When tissue-engineered cartilage containing necrotic chondrocytes was subcutaneously transplanted into C57BL/6J mice, accumulation of cartilage matrix was decreased compared to the control. Meanwhile, immunohistochemical staining demonstrated that localization of macrophages and neutrophils was more apparent in the constructs of necrotic chondrocytes, suggesting that DAMPs from necrotic chondrocytes could prompt migration of more immune cells. Two-dimensional electrophoresis and mass spectrometry identified prelamin as a significant biomolecule released from necrotic chondrocytes. Also, when prelamin was added to a culture of RAW264, Inos and Il1b were increased in accordance with the content of added prelamin. It was suggested that DAMPs from dying chondrocytes could induce inflammatory properties in surrounding macrophages, impairing the maturation of tissue-engineered cartilage. In conclusion, maturation of tissue-engineered cartilage was hampered when less viable chondrocytes releasing DAMPs were included. Impact statement In regenerative medicine, the quality of cells is of great importance to secure clinical safety. During culture, damage of cells could occur, if not critical enough to cause immediate cell death, but still inducing a less viable status. Damage-associated molecular patterns (DAMPs) are released from necrotic cells, but their influence in regenerative medicine has yet to be clarified. In this study, we elucidated how DAMPs from chondrocytes could affect the maturation of tissue-engineered cartilage. Also, possible DAMPs from necrotic chondrocytes were comprehensively analyzed, and prelamin was identified as a significant molecule, which may serve for detecting the existence of necrotic chondrocytes.