COVID-19, stigma, and habituation: evidence from mobility data.

BACKGROUND: The Japanese government has restricted people's going-out behavior by declaring a non-punitive state of emergency several times under COVID-19. This study aims to analyze how multiple policy interventions that impose non-legally binding restrictions on behavior associate with people's going-out. THEORY: This study models the stigma model of self-restraint behavior under the pandemic with habituation effects. The theoretical result indicates that the state of emergency's self-restraint effects weaken with the number of times. METHODS: The empirical analysis examines the impact of emergency declarations on going-out behavior using a prefecture-level daily panel dataset. The dataset includes Google's going-out behavior data, the Japanese government's policy interventions based on emergency declarations, and covariates that affect going-out behavior, such as weather and holidays. RESULTS: First, for multiple emergency declarations from the beginning of the pandemic to 2021, the negative association between emergency declarations and mobility was confirmed in a model that did not distinguish the number of emergency declarations. Second, in the model that considers the number of declarations, the negative association was found to decrease with the number of declarations. CONCLUSION: These empirical analyses are consistent with the results of theoretical analyses, which show that the negative association between people's going-out behavior and emergency declarations decreases in magnitude as the number of declarations increases.

Improvement impact of nudges incorporated in environmental education on students' environmental knowledge, attitudes, and behaviors.

This study conducted randomized controlled trials to evaluate the effectiveness of an environmental education class and the impacts of nudges and boosts implemented in this program on high school students' basic knowledge, attitudes, and behaviors regarding environmental issues in Japan. This environmental education class consisted of a lecture on reducing the use of plastic products for energy conservation in daily life, a board game for learning how to reduce plastic waste, and a worksheet for reflection. Four types of worksheets were randomly distributed: nudges, in which students were asked to set a goal regarding their level of effort in not throwing away plastic products such as plastic bags, wet wipes, and plastic bottles; boosts, in which participants were asked to write an essay to help increase their empathy for the parties impacted by environmental issues; both nudges and boosts; and none (neither nudges nor boosts). After environmental education, an end-line survey was conducted to evaluate the effectiveness of this class. This study found that the environmental education class significantly improved students' basic environmental knowledge and promoted their concerns about plastic waste. Although there was no evidence that nudges and boosts amplify the effects of the environmental education class on the students' knowledge, nudges were successful in making them more concerned about plastic waste. The results showed that students who received nudges or boosts were more likely to refuse free wet wipes offered at convenience stores but were not more likely to refuse plastic bottles. These results also indicated that interventions through environmental education can change students' pro-environmental behaviors only if the cost of behavioral change is low. The environmental education class not only increased students' environmental knowledge and attitudes, but the use of worksheets in administering nudges and boosts ensured the effectiveness of environmental education.

COVID-19 and Stigma: Evolution of Self-restraint Behavior.

Social stigma can effectively prevent people from going out and possibly spreading COVID-19. Using the framework of replicator dynamics, we analyze the interaction between self-restraint behavior, infection with viruses such as COVID-19, and stigma against going out. Our model is analytically solvable with respect to an interior steady state in contrast to the previous model of COVID-19 with stigma. We show that a non-legally binding policy reduces the number of people going out in a steady state.

Histological analysis of dental pulp response in immature or mature teeth after extra-oral subcutaneous transplantation into mice dorsum.

PURPOSE: The aim of this study was to assess the response of dental pulp associated with donor or host cells in the pulp chamber and root canal after extra-oral transplantation. METHODS: Wild type or green fluorescent protein (GFP) transgenic first molars from 3-week, 6-week, and 12-week mice were transplanted into the subcutaneous layer of GFP mice or wild type mice. The teeth were histologically and immunohistochemically examined at 5 weeks after transplantation. RESULTS: Blood vessels present in the original coronal pulp had anastomosed with those from the recipient tissue that had invaded the root canal. Two distinct eosin-stained extracellular matrices were observed in the pulp chamber and root canal. Acellular matrix composed of nestin-positive, odontoblast-like cells invaded from the outside and was seen in the root canal of 3-week teeth. Cellular matrix comprising alkaline phosphatase (ALP)-positive fibroblast-like cells appeared in the original coronal pulp. In the root canal of the 6-week and 12-week teeth, cellular extracellular matrix consisting of ALP-positive fibroblast-like cells had invaded the recipient tissue. CONCLUSION: Dental pulp from immature teeth might be able to regenerate dentin-like tissue. This model could be useful in the development of an optimized vitalization treatment.

Computed tomographic features of synovial chondromatosis of the temporomandibular joint with a few small calcified loose bodies.

OBJECTIVES: The present study aimed to clarify the characteristic computed tomography (CT) features that indicate synovial chondromatosis (SC) with a few small calcified bodies or without calcification on panoramic images, and to discuss their differences from the features of temporomandibular disorder (TMD). METHODS: Panoramic and CT images from 11 patients with histologically verified SC of the temporomandibular joint were investigated. Based on the panoramic images, the patients were classified into a distinct group (5 patients) with typical features of calcified loose bodies and an indistinct group (6 patients) without such bodies. On the CT images, findings for high-density structures suggesting calcified loose bodies, joint space widening, and bony changes in the articular eminence and glenoid fossa (eminence/fossa) and condyle were analyzed. RESULTS: All 5 distinct group patients showed high-density structures on CT images, while 2 of 6 indistinct group patients showed no high-density structures even on soft-tissue window CT images. A significant difference was found for the joint space distance between the affected and unaffected sides. A low-density area relative to the surrounding muscles, suggesting joint space widening, was observed on the affected side in 2 indistinct group patients. All 11 patients regardless of distinct or indistinct classification showed bony changes in the eminence/fossa with predominant findings of extended sclerosis and erosion. CONCLUSION: Eminence/fossa osseous changes including extended sclerosis and erosion may be effective CT features for differentiating SC from TMD even when calcified loose bodies cannot be identified.

COVID-19 with Stigma: Theory and Evidence from Mobility Data.

This study conducts both theoretical and empirical analyses of how non-legally-binding COVID-19 policies affect people's going-out behavior. The theoretical analysis assumes that under a declared state of emergency, the individual going out suffers psychological costs arising from both the risk of infection and the stigma of going out. Our hypothesis states that under a declared state of emergency people refrain from going out because it entails a strong psychological cost. Then, this study estimates a model using regional mobility data and emergency declarations data to analyze self-restraint behavior under a non-legally binding emergency declaration. The results show that, compared with before the declaration of the state of emergency, going-out behavior was suppressed under the state of emergency and after it was lifted even when going out did not result in penalties, which is consistent with the theoretical analysis.

Performance of Schwann cell transplantation into extracted socket after inferior alveolar nerve injury in a novel rat model.

An inferior alveolar nerve (IAN) injury is a common clinical problem that can affect a patients' quality of life. Cellular therapy has been proposed as a promising treatment for this injury. However, the current experimental models for IAN injury require surgery to create bone windows that expose the nerve, and these models do not accurately mimic human IAN injuries. Therefore, in this study, a novel experimental model for IAN injury has been established in rats. Using this model, the effects of Schwann cells and their role in the recovery from IAN injuries were investigated. Schwann cells were isolated from rat sciatic nerves and cultured. The first molar in the mandible was extracted and the IAN was immediately injured for 30 min by inserting an insect pin. Then, the Schwann cells or culture medium were transplanted into the extracted sockets of the cell and injury groups, respectively. After the surgery, the cell group displayed significantly increased sensory reflexes in response to mechanical stimulation, regenerated IAN width, and myelin basic protein-positive myelin sheaths when compared with the injury group. In conclusion, a novel animal experimental model for IAN injury has been developed that does not require the creation of a bone window to evaluate the impacts of cell transplantation and demonstrates that Schwann cell transplantation facilitates the regeneration of injured IANs.

Efficacy of therapeutic exercise for temporomandibular disorders as assessed by magnetic resonance imaging: a case report.

[Purpose] The efficacy of exercise therapy in temporomandibular disorders has been recognized. Here, we present our experience with exercise therapy. [Participant and Methods] A 25-year-old female with a sudden onset of mouth opening limitation in October 2018 was admitted to our hospital in November 2018. Based on our initial findings, the patient was diagnosed with left disc derangement of the temporomandibular joint without reduction. A definitive diagnosis was established following magnetic resonance imaging in December 2018. Subsequently, range-of-motion exercises for the temporomandibular joint as passive movements and self-traction therapy as active movements were conducted. Magnetic resonance imaging was repeated 4 months after the first treatment. [Results] The temporomandibular joint disc remained in anterior dislocation during mouth opening and closing. The mouth opening joint motion was significantly improved compared to the pre-therapy range. The pain-related visual analog scale score also significantly improved. [Conclusion] The range of motion of the temporomandibular joint was improved by range-of-motion exercises for the temporomandibular joint, and was maintained and managed using self-traction therapy. Improvement of the range of motion was confirmed by magnetic resonance imaging.

Clinical guidelines for total temporomandibular joint replacement.

Total joint replacement (TJR) of the temporomandibular joint (TMJ) is a promising surgical procedure and device for treating end-stage diseases of the TMJ. For the functional and aesthetic reconstruction of the oral and maxillofacial head and neck region, TMJ TJR significantly helps maintain the patient's quality of life in terms of a better diet, mastication, speech and social interaction. TMJ TJR was approved by regulatory authorities in 2019 in Japan, thus enabling the clinical application of the TJR system. However, the surgery demands particularly difficult and high-risk procedures, necessitating the prudent selection of indicated patients. The joint committee of the Japanese Society of Oral and Maxillofacial Surgeons and Japanese Society for Temporomandibular Joint is working together to develop an appropriate clinical guideline for TMJ TJR.

Transplantation of human dental pulp stem cells ameliorates diabetic polyneuropathy in streptozotocin-induced diabetic nude mice: the role of angiogenic and neurotrophic factors.

BACKGROUND: Dental pulp stem cells (DPSCs) have high proliferation and multi-differentiation capabilities that maintain their functionality after cryopreservation. In our previous study, we demonstrated that cryopreserved rat DPSCs improved diabetic polyneuropathy and that the efficacy of cryopreserved rat DPSCs was equivalent to that of freshly isolated rat DPSCs. The present study was conducted to evaluate whether transplantation of cryopreserved human DPSCs (hDPSCs) is also effective for the treatment of diabetic polyneuropathy. METHODS: hDPSCs were isolated from human impacted third molars being extracted for orthodontic reasons. Eight weeks after the induction of diabetes in nude mice, hDPSCs (1 × 105/limb) were unilaterally transplanted into the hindlimb skeletal muscle, and vehicle (saline) was injected into the opposite side as a control. The effects of hDPSCs were analyzed at 4 weeks after transplantation. RESULTS: hDPSC transplantation significantly ameliorated reduced sensory perception thresholds, delayed nerve conduction velocity, and decreased the blood flow to the sciatic nerve in diabetic mice 4 weeks post-transplantation. Cultured hDPSCs secreted the vascular endothelial growth factor (VEGF) and nerve growth factor (NGF) proteins. A subset of the transplanted hDPSCs was localized around the muscle bundles and expressed the human VEGF and NGF genes at the transplanted site. The capillary/muscle bundle ratio was significantly increased on the hDPSC-transplanted side of the gastrocnemius muscles in diabetic mice. Neutralizing antibodies against VEGF and NGF negated the effects of hDPSC transplantation on the nerve conduction velocity in diabetic mice, suggesting that VEGF and NGF may play roles in the effects of hDPSC transplantation on diabetic polyneuropathy. CONCLUSIONS: These results suggest that stem cell transplantation with hDPSCs may be efficacious in treating diabetic polyneuropathy via the angiogenic and neurotrophic mechanisms of hDPSC-secreted factors.

Serum Metabolic Profiles of the Tryptophan-Kynurenine Pathway in the high risk subjects of major depressive disorder.

Previous reports have shown that during chronic inflammation, the tryptophan (TRP)-kynurenine (KYN) pathway plays a pivotal role in the onset of depression. The aim of this study was to investigate the characteristics of the serum TRP-KYN pathway metabolite profile in high-risk subjects of major depressive disorder (HRMDD) defined by depression scores. The concentrations of TRP-KYN pathway metabolites {TRP, KYN, 3-hydroxyanthranilic acid (3HAA), 3-hydroxykynurenine (3HK), kynurenic acid (KYNA) and anthranilic acid (AA)} were assessed in serum from HRMDD, chronic pain disorder patients and healthy controls. In serum from HRMDD, elevated levels of AA and decreased levels of TRP were observed, but the levels of other metabolites were not changed. Furthermore, the change in the AA2nd/AA1st ratio in subjects who progressed from a health. y state to a depressive state was correlated with an increase in the CES-D score. The level of IL-1 receptor antagonist (IL-1RA) was negatively correlated with that of AA. Interestingly, we confirmed AA as a possible biomarker for depression-related symptoms, since the metabolite profiles in the chronic pain disorder group and chronic unpredictable mild stress model mice were similar to those in the HRMDD. These results suggest that AA may be an effective marker for HRMDD.

Recovery of sensory function after the implantation of oriented-collagen tube into the resected rat sciatic nerve.

INTRODUCTION: In the present study, we examined the effect of oriented collagen tube (OCT) implantation on the recovery of sensory function of the resected rat sciatic nerve. MATERIALS AND METHODS: After a 10-mm long portion of the sciatic nerve of a rat was resected, an OCT was placed in the site of nerve defect. Recovery of the sensory function was evaluated using Von Frey test every 3 days after surgery. The regenerated tissue were histologically and ultrastructurally analyzed 2 and 4 weeks after the surgery. RESULTS: The sensory reflexes of the OCT group were restored to the level of that of the intact group after 15 days. Hematoxylin and eosin staining revealed the cross-linking between the proximal and distal stumps after 2 weeks. After 4 weeks, Luxol Fast Blue and immunohistochemical staining revealed the presence of myelin sheath from the proximal to distal region of the regenerated tissue and S100B staining confirmed the presence of Schwann cells. Interestingly, no myelin sheath was ultrastructurally observed around the regenerated axons at the central region after 2 weeks. CONCLUSIONS: These results suggest that OCTs facilitate the recovery of sensory function. Additionally, the non-myelinated axons contributed to the recovery of the sensory function.

Reliability of diagnostic imaging for degenerative diseases with osseous changes in the temporomandibular joint with special emphasis on subchondral cyst.

OBJECTIVES: The present study aimed to clarify the reliabilities of four characteristic appearances, subchondral cyst, erosion, generalized sclerosis, and osteophyte, for evaluation of degenerative diseases with osseous changes in the temporomandibular joint (TMJ) using panoramic TMJ projection imaging and computed tomography (CT), and to investigate the imaging features of these modalities for subchondral cyst with reference to its magnetic resonance imaging (MRI) features. METHODS: The reliabilities (κ values) of panoramic TMJ projection and CT images were determined by three radiologists for each characteristic appearance of TMJ osseous changes in 146 condyles. The features of cyst-like areas on CT images with agreement among the three radiologists were investigated for size, location, and continuity with the joint space together with MRI signal intensity and surrounding edema-like lesions. RESULTS: Panoramic TMJ projection images showed moderate and substantial agreements for erosion and osteophyte evaluations, respectively; while CT images showed substantial agreements for subchondral cyst, erosion, and osteophyte evaluations. Cyst-like areas on CT images were predominantly located in the central parts and 69 of 86 (80.2%) areas showed no communication with the joint space. Cyst-like areas with diameters exceeding 2 mm showed high or moderate MRI signal intensities. Edema-like lesions were observed in 10 of 28 (29.4%) condyles. CONCLUSIONS: The reliabilities of panoramic TMJ projection and CT images were clarified for each characteristic appearance. The results support the bone contusion theory for the formation of subchondral cysts in the TMJ. A possible improvement in reliability is suggested relative to MRI findings.

Correlation between prognostic nutritional index and occlusal status in gastric cancer.

OBJECTIVE: Systemic inflammatory responses in cancer patients are important factors for nutrition and prognosis. This study evaluates the association between tooth loss, occlusal status, and prognostic nutritional index (PNI). METHODS: A total of 93 patients with gastric cancer were included. These parameters were investigated the following: stage, body mass index (BMI), total lymphocyte count, C-reactive protein (CRP), PNI, and albumin (ALB). Patients were divided into three groups by Eichner classification (group A had contact in four support zones; group B had in one to three zones or in anterior region; and group C had no contact). PNI assumed 40 or less undernutrition. Multiple regression analysis was performed (PNI, dependent variable; Eichner index, main independent variable), using four independent variables (sex, age, BMI, and CRP) as adjustment factors. RESULTS: The mean ± SD PNI in groups A, B, and C was 43.0 ± 4.7, 41.7 ± 5.2, and 36.7 ± 7.7, respectively. A significant positive correlation was found between the number of teeth, both ALB, and PNI. ALB and PNI differed significantly between groups A and C (ALB, p = .0003; PNI, p = .005). CONCLUSION: We recommend a preoperative dental evaluation for assessing the nutritional status of patients with gastric cancer.

Nasometric Scores in spinal and bulbar muscular atrophy - Effects of palatal lift prosthesis on dysarthria and dysphagia.

Spinal and bulbar muscular atrophy (SBMA) is a hereditary neuromuscular disease affecting only males characterized by progressive muscular atrophy and weakness in bulbar and limb muscles. The present study aimed to evaluate the features of velopharyngeal dysfunction (VPD) in SBMA subjects by an acoustic analysis of speech. Twenty-three genetically confirmed patients with SBMA were enrolled and assessed their speech by measuring the nasalance score with a Nasometer II. The nasalance scores of the SBMA group was higher than that of healthy controls (p = .035) and significantly correlated with the total score of the revised amyotrophic lateral sclerosis functional rating scale (rs = -0.520, p = .011). On the basis of the results of the VPD study, the efficacy of a palatal lift prosthesis (PLP) was assessed in two patients with SBMA to treat their VPD. The PLP improved dysarthria in both cases, although the impact of the prosthesis on dysphagia was not consistent. The present study suggested that the nasalance score is a useful quantitative measurement to evaluate VPD in patients with SBMA. A PLP may improve dysarthria in SBMA patients by reducing VPD, but the clinical application of this procedure should be considered carefully in view of its possible negative effect on dysphagia.

Cheek-splitting technique for marginal mandibulectomy: A novel approach.

When performing marginal mandibulectomy, ensuring complete tumor removal and preventing postoperative iatrogenic mandibular fracture are essential. Pathological fracture can result due to stress concentration at the site requiring acute angle resection. To perform marginal mandibulectomy without making acute angles in patients with a lesion in the molar or more posterior region, a submandibular or transbuccal approach is necessary. Compared to the submandibular approach, the transbuccal approach is considered useful as it reduces operative time and prevents injury to the facial and mental nerves. Additionally, this approach does not leave a scar in the surgical field, which is beneficial in subsequent neck dissection for late neck metastasis. Here, we report 2 cases of lower gingival carcinoma in which satisfactory aesthetic outcomes were achieved with an improved cheek-splitting technique for marginal mandibulectomy using a transbuccal approach, taking into consideration the angle of the mouth, design of the triangular flap, and modiolus. Key words:Mandibular gingival carcinoma, cheek-splitting technique, transbuccal approach, marginal mandibulectomy.

Multiple mucoceles of the lower lip: A case report.

A 2-year-old girl developed three mucoceles on lower lip, probably due to her habit of rolling lower lip behind the maxillary anterior teeth. The spacing in the dentition and mechanical irritation from habitual lip biting may have caused the mucoceles. At 3 years after excision surgery, the patient remained recurrence-free.

Technique for secondary modification after maxillary resection and reconstruction for soft tissue flap fixation before prosthesis addition: a case report.

BACKGROUND: The removal of maxillary carcinoma causes various types of tissue defects, which can be corrected by free flap reconstruction. In flap reconstruction after maxillary cancer resection, ensuring prosthesis stability is frequently difficult owing to the flap's weight. Therefore, a second modification technique is required for improvement of configuration. This case where flap suspension and flap modifying surgery were performed using anchor system for the extensive complete maxillectomy case. CASE PRESENTATION: The patient was a 56-year-old male, who underwent an extensive total maxillectomy and flap reconstruction using the rectus abdominus muscles in May 2005. Postoperatively, due to the difficulties of wearing a maxillary denture, he was transferred to our department with the chief complaint of morphological improvement. The maxillary bone had already been removed from the midline with the rectus abdominus muscle flap sutured directly to the soft palate without oral vestibule, and the flap margin was moving together with the surrounding soft tissue. The flap size was 70 × 50 mm, which was sagging due to its own weight and was in contact with mandibular molars, reducing the volume of the oral cavity without a denture being worn. Flap reduction and lifting the flap were performed under general anesthesia using 3 Mitek anchors implanted in the zygomatic bone, and the anchor suture was placed through the subcutaneous tissue to lift the flap. Postoperatively, the prosthesis was stable. No recurrence of flap sagging or wound infection was seen 3 years after surgery. CONCLUSIONS: The second modification technique after maxillary cancer resection is useful for ensuring prosthesis stability. This method can be used before prosthesis addition. We could obtain remarkable denture stability by flap suspension using anchor system and a flap-modifying operation for the patient who had undergone maxilloecotomy. The denture was stabilized by using anchors for the elevated flap and flap loss technique and by performing vestibuloplasty for support.

Effect of antidepressant treatment on plasma levels of neuroinflammation-associated molecules in patients with somatic symptom disorder with predominant pain around the orofacial region.

OBJECTIVE: Burning mouth syndrome (BMS) and atypical odontalgia (AO) are examples of somatic symptom disorders with predominant pain around the orofacial region. Neuroinflammation is thought to play a role in the mechanisms, but few studies have been conducted. We aimed to better understand the role of neuroinflammation in the pathophysiology and treatment of BMS/AO. METHODS: Plasma levels of 28 neuroinflammation-related molecules were determined in 44 controls and 48 BMS/AO patients both pretreatment and 12-week post-treatment with duloxetine. RESULTS: Baseline plasma levels of interleukin (IL)-1ß (p < .0001), IL-1 receptor antagonist (p < .001), IL-6 (p < .0001), macrophage inflammatory protein-1ß (p < .0001), and platelet-derived growth factor-bb (.04) were significantly higher in patients than in controls. Plasma levels of granulocyte macrophage colony stimulating factor were significantly higher in patients than in controls (p < .001) and decreased with treatment (.009). Plasma levels of eotaxin, monocyte chemoattractant protein-1, and vascular endothelial growth factor decreased significantly with treatment (p < .001, .022, and .029, respectively). CONCLUSIONS: Inflammatory mechanisms may be involved in the pathophysiology and/or treatment response of somatic symptom disorders with predominant pain around the orofacial region.