Publications by authors named "Hayasaki H"

Background: This study investigated the correlation between the prevalence of dental caries and the presence and type of abuse.

Methods: Participants were 534 children admitted for care at two child guidance centers (CGCs) in Niigata, Japan. Data pertaining to abuse, including the reason for temporary protective care and the type of abuse, and the oral examination results of the children, were collected.

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Background: There is growing interest in the development of objective methods for assessing lip-closing function in children.

Objective: To obtain normative data for healthy children in the developmental stages of lip closure function, we quantitatively evaluated oral movements associated with lip closure in children and adults using a composite sensor (CS).

Methods: Twenty-five normal children (11 boys, 14 girls) aged 8.

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Background: We previously reported a novel technique for fabricating dermo-epidermal junction (DEJ)-like micropatterned collagen scaffolds to manufacture an produced oral mucosa equivalent (EVPOME) for clinical translation; however, more biomimetic micropatterns are required to promote oral keratinocyte-based tissue engineering/regenerative medicine. In addition, in-process monitoring for quality control of tissue-engineered products is key to successful clinical outcomes. However, evaluating three-dimensional tissue-engineered constructs such as EVPOME is challenging.

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Alpha-thalassemia X-linked intellectual disability (ATR-X) syndrome affects males and is associated with profound developmental delay, facial dysmorphism, genital abnormalities, and alpha thalassemia. Appropriate oral health management for affected patients is important. The purposes of this report are to describe a case involving six years of oral health management, including training in eating, drinking and swallowing, for a patient with ATR-X syndrome, and to discuss the morphological and functional oral characteristics of this disorder.

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Objectives: Weakening of lip-closing strength (LCS) associated with an incompetent lip seal (ILS) may affect the oral balance between the lip and tongue pressures. The purpose of this study was to evaluate the effects of lip-closing training in children with lower LCS and/or abnormal habits across different age groups and to compare its effects on increasing LCS in children with malocclusion and/or oral habits.

Material And Methods: Lip-closing training was performed by 154 Japanese children aged 3-12 years using a specialized training device at home for 3 months.

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Background/aim: Root length is a critical factor for dental pulp regeneration following tooth replantation. The aim of this study was to analyze the effects of reducing the root length by apicoectomy on the pulp healing process using a model for tooth replantation.

Material And Methods: After extraction of the upper first molars (M1) of 3-week-old mice, the roots from the experimental group (EG) were shortened to half to two-thirds of their length before replantation, whereas in the control group (CG) the extracted teeth were immediately repositioned into their alveolar sockets.

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Background: Understanding the refinement of self-feeding skills is useful for the assessment of oral functional development in children.

Objectives: To determine normative data on lip closing during food intake in the development of independent spoon-feeding in normal children, we tested the hypothesis that lip-closing pressure and spoon operation differ depending on food type.

Methods: Fifteen normal children (eight boys, seven girls; mean age: 6.

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Background: Systemic and local factors may lead to disruption of craniofacial growth and development, causing an imbalance between the orofacial skeleton, muscle and soft tissue, dental occlusion, and the dental arch during growth periods. We aimed to reveal whether the prevalence of incompetent lip seal (ILS) varies with age and region, as well as to clarify the factors related to an ILS, in a national, large-scale epidemiological study.

Methods: We surveyed 3399 children, from 3 to 12 years of age, visiting 66 pediatric dental clinics throughout Japan.

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Pluripotent stem cells are classified as naïve and primed cells, based on their in vitro growth characteristics and potential to differentiate into various types of cells. Human-induced pluripotent stem cells (iPSCs, also known as epiblast stem cells [EpiSCs]) have limited capacity to differentiate and are slightly more differentiated than naïve stem cells (NSCs). Although there are several in vitro protocols that allow iPSCs to differentiate into pancreatic lineage, data concerning generation of β-cells from these iPSCs are limited.

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The present study aimed to develop a more biomimetic tissue-engineered oral mucosa equivalent comprising 1% type I tilapia scale collagen scaffold having microstructures mimicking the dermal-epidermal junction of oral mucosa and oral keratinocytes as graft materials for human use. We designed four micropattern prototypes mimicking the dermal-epidermal junction. Using a semiconductor process and soft lithography, negative molds were fabricated to develop microstructures using both polydimethylsiloxane and silicon substrates.

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Lip closing is an important motor act in food acquisition. Appropriate food capture in anticipatory and early oral stages of feeding is essential for mastication and swallowing. The aim of this study was to investigate the effect of food type and quantity on lip closing pressure during food capture with a spoon, and to identify normal lip function during food acquisition in healthy young adults.

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Human tissue-specific stem cells (hTSCs), found throughout the body, can differentiate into several lineages under appropriate conditions in vitro and in vivo. By transfecting terminally differentiated cells with reprogramming factors, we previously produced induced TSCs from the pancreas and hepatocytes that exhibit additional properties than iPSCs, as exemplified by very low tumour formation after xenogenic transplantation. We hypothesised that hTSCs, being partially reprogrammed in a state just prior to iPSC transition, could be isolated from any terminally differentiated cell type through transient reprogramming factor overexpression.

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Background: Molar incisor hypomineralization (MIH) frequently occurs in children worldwide. However, MIH prevalence throughout Japan has not yet been investigated. The purpose of this study was to clarify MIH prevalence rates and to consider potential regional differences throughout Japan.

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Streptococcus pyogenes is a bacterium that causes systemic diseases such as pharyngitis and toxic shock syndrome. S. pyogenes produces molecules that inhibit the function of the human immune system, thus allowing growth and spread of the pathogen in tissues.

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Objective: Mouth breathing syndrome (MBS) is defined as a set of signs and symptoms that may be completely or incompletely present in subjects who, for various reasons, replace the correct pattern of nasal breathing with an oral or mixed pattern. It is important to identify the relevant factors affecting MBS in order to diagnose its cause since breathing obstructions can result from multiple factors. The purpose of this study is to clarify the relevant factors and the interrelationships between factors affecting MBS among children.

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Streptococcus pyogenes is a bacterium that causes systemic diseases, such as pharyngitis and toxic shock syndrome, via oral- or nasal-cavity infection. S. pyogenes produces various molecules known to function with serum components that lead to bacterial adhesion and invasion in human tissues.

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Objective: Lymphoid enhancer-binding factor-1 (LEF1) is a 48-kD nuclear protein that is expressed in pre-B and T cells. LEF1 is also an important member of the Wnt/β-catenin signaling pathway that plays important roles in the self-renewal and differentiation of embryonic stem cells. We speculated that LEF1 might function in the stem cells from human exfoliated deciduous teeth (SHED).

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Type 1 diabetes occurs due to the autoimmune destruction of pancreatic β-cells in islets. Transplantation of islets is a promising option for the treatment of patients with type 1 diabetes that experience hypoglycemic unawareness despite maximal care, but the present shortage of donor islets hampers such transplantation. Transplantation of insulin-producing cells derived from the patients themselves would be one of the most promising approaches to cure type 1 diabetes.

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Feeder cells are generally required to maintain embryonic stem cells (ESCs)/induced pluripotent stem cells (iPSCs). Mouse embryonic fibroblasts (MEFs) isolated from fetuses and STO mouse stromal cell line are the most widely used feeder cells. The aim of this study was to determine which cells are suitable for establishing iPSCs from human deciduous tooth dental pulp cells (HDDPCs).

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Streptococcus pyogenes produces molecules that inhibit the function of human immune system, thus allowing the pathogen to grow and spread in tissues. It is known that S. pyogenes CAMP factor increases erythrocytosis induced by Staphylococcus aureus β-hemolysin.

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Hyaluronan (HA) and its binding molecules, cartilage link protein (LP) and proteoglycan (PG), are structural components of the hydrated extracellular matrix. Because these molecules play important roles in the tumor microenvironment, we examined the distribution of HA, LP, versican, and aggrecan in salivary gland tumors using histochemical and immunohistochemical methods, including double staining. LP was present in pleomorphic adenoma (PA) and adenoid cystic carcinoma (ACC) tissues, and aggrecan was absent in the malignant tumors that we investigated.

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Radiation necrosis (RN) after intensive radiation therapy is a serious problem. Using human RN specimens, we recently proved that leaky angiogenesis is a major cause of brain edema in RN. In the present study, we investigated the same specimens to speculate on inflammation's effect on the pathophysiology of RN.

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Objective: The aim of this study was to demonstrate the effectiveness of an analysis of tooth brushing cycles using a system that measures tooth brushing motion and brushing force with an accelerometer and strain tension gage attached to a toothbrush.

Background: Mechanical plaque removal with a manual toothbrush remains the primary method of maintaining good oral hygiene for the majority of the population. Because toothbrush motion has not been fully understood, it should be clarified by analysis of tooth brushing cycles.

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STO feeder cells, a line established from mouse SIM embryonic fibroblasts, have been frequently used for establishing embryonic stem cells and maintaining them in an undifferentiated state. There are some reports demonstrating that fibroblastic cells have the ability to phagocytose Gram-positive bacterium (e.g.

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