Dental caries prevalence in children during temporary protective care according to type of abuse.

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. These results were then compared with those of a national survey and analyzed in relation to the presence and type of abuse. RESULTS: The odds ratio for decayed teeth was 4.1, indicating a higher risk in children admitted to the CGCs. However, no significant association was found between the presence of decayed, filled, or caries-experienced teeth and the presence of abuse. A significant positive association was observed between dental caries and one type of abuse, indicating a greater prevalence of dental caries in cases of neglect. The findings of this study suggest that the type of abuse, rather than its presence, is associated with dental caries. CONCLUSIONS: Our findings suggest that proactive support should be provided to children in problematic nurturing environments, regardless of whether they have been subjected to abuse.

Evaluation of oral function using a composite sensor during maximum lip closure and swallowing in normal children and adults.

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 8.8 ± 1.6 years and 25 young adults (13 men, 12 women) aged 27.4 ± 3.9 years were asked to perform test movements, maximal lip closure and swallowing of 3 mL of water. Lip-closing pressure (LP), intraoral baro-pressure (IP) and electromyographic (EMG) activity of the upper orbicularis oris muscle were simultaneously recorded using the CS. RESULTS: EMG activity of the upper orbicularis oris muscle during closure was significantly greater in adults than in children. There were significant positive correlations between integral values of LP and EMG for closure in adults (r = .527, p = .008) but not in children, and significant positive correlations between integral values of LP and IP for swallowing in children (r = .508, p = .010) but not in adults. CONCLUSIONS: The CS may provide an effective tool for evaluating lip function in children acquiring oral function. For the combination of maxillary orbicularis oculus contraction and formation of intraoral negative pressure, EMG activity of the upper orbicularis oris muscle involvement in LP and IP involvement in LP may differ between children and adults.

Lip-closing strength in children is enhanced by lip and facial muscle training.

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. Children with oral habits and/or exhibiting less than standard LCS were included. LCS was measured using a digital strain force gauge at a dental clinic at the beginning (T0) and after each month (after 3 months: T3). RESULTS: Children had higher LCS responses after lip-closing training. The first month of lip-closing training was more effective than the subsequent months. With lip-closing training, the LCS increased from an average of 6.2 N (T0) to 11.4 N (T3) in Group I, 7.9 N (T0) to 12.8 N (T3) in Group II, and 6.8 N to 11.4 N in Group III. Anterior cross bite, including reverse bite, open bite, and tongue thrusting, significantly reduced training effects. CONCLUSION: Our findings showed that lower LCS in children with ILS resulted in greater responses to lip-closing training in a short period, but oral dysfunction, such as abnormal habits, inhibited the positive effects of training. Our results suggest that less detrimental effects of malocclusion and abnormal oral habits lip-closing training enhances LCS in younger children.

Oral Function and Feeding Management in a Child with Alpha Thalassemia X-Linked Intellectual Disability Syndrome.

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. The patient's oral dysfunctions were incompetent lip-closing, inappropriate tongue protrusion, deviation of chewing acquisition, and incompetent oral and pharyngeal bolus propulsion. Other problems included inappropriate ingestion posture, low interest in meals, and poor oral hygiene. A stable oral intake and an improved eating posture were achieved through an intervention; however, the patient's inappropriate tongue protrusion, deviation of chewing acquisition, and incompetent bolus propulsion remained unchanged.

The effects of reducing the root length by apicoectomy on dental pulp revascularization following tooth replantation in mice.

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. To determine the effects of root resection on the survival of inherent pulp cells, this study included tooth transplantation with root resection using wild-type (WT) and green fluorescent protein (GFP) transgenic mice. The M1 of GFP transgenic mice were transplanted into the alveolar socket of the M1 of WT mice. The roots of the right M1 were shortened (EG), whereas the left M1 remained untreated (CG). RESULTS: Apoptotic cells in the EG significantly decreased in number compared with the CG at day 3. Cell proliferative activity in the EG was significantly higher than that in the CG in the root pulp during days 3-5, and nestin-positive odontoblast-like cells began to arrange themselves along the pulp-dentin border in the cusp area at day 5 in the EG but not in the CG. At week 2, tertiary dentin had formed throughout the pulp in the EG, whereas the combined tissue of dentin and bone occupied the pulp space in 60% of the CG. Root resection also positively affected the survival of inherent pulp cells to differentiate into odontoblast-like cells as demonstrated by transplantation using GFP transgenic mice. CONCLUSIONS: Reducing the root length accelerated pulp regeneration following tooth replantation due to the better environment for revascularization.

Lip-closing pressure during food intake from a spoon in normal children.

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: 6.5 years) were asked to eat test foods (2, 3 and 5 g of yogurt and cream cheese) freely with a spoon. Lip-closing pressures and kinematic data on spoon operation were recorded simultaneously with a strain gauge transducer embedded in the spoon and Vicon motion analysis, respectively. RESULTS: In the most common lip-pressure pattern, only positive pressure was generated. In the second most common pattern, negative pressure occurred first, followed by positive pressure; this pattern was seen infrequently. Positive pressure (P < .001), pressure duration (P < .001) and spoon intra-oral time (P < .05) during intake of cream cheese (an adhesive food) were significantly greater than those during intake of yogurt (a non-adhesive food). Pressure onset occurred at the beginning of the spoon withdrawal period or at the turning point from spoon insertion to withdrawal, depending on the food. CONCLUSIONS: Lip-closing force and spoon operation varied depending on food type in preschool and early elementary school children. Our findings suggest the need to consider the importance of food diversity and to pay attention to the spoon withdrawal period when assessing the development and maturation of lip function.

Prevalence of an incompetent lip seal during growth periods throughout Japan: a large-scale, survey-based, cross-sectional study.

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. For this survey, we employed a questionnaire consisting of 44 questions regarding daily health conditions and lifestyle habits. We evaluated the differences in ILS prevalence by age and region (using a Cochran-Armitage test for trend and a Kruskal-Wallis test), and the relationship between ILS and factors investigated in the questionnaire (using Spearman's rank correlation coefficient). RESULTS: We observed that 30.7% of Japanese children exhibited an ILS and that the ILS rate increased with age (p < 0.001). There were no regional differences in the rate of ILS in Japanese children (p = 0.506). We revealed that 12 of 44 survey items exhibited a statistically significant correlation with ILS (p < 0.001), using Spearman's rank correlation coefficient. These items involved orofacial morphology, mouth breathing, and possibly, allergic rhinitis. CONCLUSION: The rate of ILS seems to increase with age in children, throughout Japan. Therefore, this disorder may not self-correct during the growth periods in these children. Guidelines are required for pediatric dentists to recognize ILS among children aged 3-12 years.

Drug-Induced Naïve iPS Cells Exhibit Better Performance than Primed iPS Cells with Respect to the Ability to Differentiate into Pancreatic ß-Cell Lineage.

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 ß-cells from these iPSCs are limited. Based on the pluripotentiality of NSCs, it was hypothesized that NSCs can differentiate into pancreatic ß-cells when placed under an appropriate differentiation induction condition. We examined whether NSCs can be efficiently induced to form potentially pancreatic ß cells after being subjected to an in vitro protocol. Several colonies resembling in vitro-produced ß-cell foci, with ß-cell-specific marker expression, were observed when NSC-derived embryoid bodies (EBs) were induced to differentiate into ß-cell lineage. Conversely, EpiSC-derived EBs failed to form such foci in vitro. Intrapancreatic grafting of the in vitro-formed ß-cell foci into nude mice (BALB/c-nu/nu) generated a cell mass containing insulin-producing cells (IPCs), without noticeable tumorigenesis. These NSCs can be used as a promising resource for curing type 1 diabetes.

Development of microstructured fish scale collagen scaffolds to manufacture a tissue-engineered oral mucosa equivalent.

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. Micropattern configurations of dermal-epidermal junctions manufactured from fish collagen consisting of a fibril network using our micropatterning system were well preserved, although the internal fibril network of the pillar pattern was sparse. Mixing 1% chondroitin sulfate with the collagen matrix minimized tissue-engineered oral mucosa equivalent contraction. Histologic examinations showed a flattening of the vertical dimensions of all microstructures and expansion of their pitches, indicating changes in the originally designed configurations. Nonetheless, histologic examinations revealed that a fully differentiated and stratified epithelial layer was developed on all scaffolds, suggesting that the microstructured fish scale collagen scaffolds have potential in the manufacturing of tissue-engineered oral mucosa equivalents for clinical use; however, enhancement of the mechanical properties of micropatterns is required. Our micropatterning technology can also apply to the development of oral mucosa in vitro models.

Influence of food adhesivity and quantity in lip closing pressure.

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. Twenty young healthy males (age range: 22-30 years) participated in this study. They were asked to eat the test food freely with a spoon. Test foods were yogurt and cream cheese, which were given in quantities of 3, 5 and 10 g in weight; 3 ml water was included as a reference. A strain gauge transducer was embedded in the spoon in advance, and lip closing pressures during food capture were measured and recorded. The Vicon motion analysis system was used to collect three-dimensional kinematic data of spoon operation. Positive pressure with lip closing during capture of adhesive food, such as cream cheese, significantly increased (P < 0.001). Moreover, positive pressure significantly decreased when food quantity increased (P < 0.01), irrespective of food type. Negative pressure that preceded positive pressure appeared more frequently during cream cheese intake and increased when food quantity on the spoon increased (P < 0.001). These findings indicated that participants sucked or squeezed the spoon further during capture of adhesive food. Maximum mouth opening occurred predominantly during the spoon insertion period, while mouth closing occurred predominantly during the spoon withdrawal period. After mouth closing, all subsequent lip pressure events appeared in the withdrawal period. Our results may be useful for comprehending normal lip function during food acquisition in healthy young adults. They may also aid in the diagnosis and management of abnormal lip function in oral hypofunction and dysfunction, which can be examined in future studies.

Repeated human deciduous tooth-derived dental pulp cell reprogramming factor transfection yields multipotent intermediate cells with enhanced iPS cell formation capability.

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. Cytochemical staining of human deciduous tooth-derived dental pulp cells (HDDPCs) and human skin-derived fibroblasts following transfection with Yamanaka's factors demonstrated increased ALP activity, a stem cell marker, three weeks after transfection albeit in a small percentage of clones. Repeated transfections (≤3) led to more efficient iPSC generation, with HDDPCs exhibiting greater multipotentiality at two weeks post-transfection than the parental intact HDDPCs. These results indicated the utility of iPSC technology to isolate TSCs from HDDPCs and fibroblasts. Generally, a step-wise loss of pluripotential phenotypes in ESCs/iPSCs occurs during their differentiation process. Our present findings suggest that the reverse phenomenon can also occur upon repeated introduction of reprogramming factors into differentiated cells such as HDDPCs and fibroblasts.

Prevalence of molar incisor hypomineralization and regional differences throughout Japan.

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. METHODS: A total of 4496 children aged 7-9 years throughout Japan were evaluated in this study. MIH prevalence rates among children were evaluated in eight regions throughout Japan. A child's residence was defined as the mother's residence during pregnancy. The localization of demarcated opacities and enamel breakdown was recorded on a standard code form using a guided record chart. Logistic regression analysis was used to evaluate whether MIH prevalence rates differed among age groups, sex, and regions. RESULTS: The overall prevalence of MIH in Japan was 19.8%. The prevalence of MIH was 14.0% in the Hokkaido region, 11.7% in the Tohoku region, 18.5% in the Kanto Shin-Etsu region, 19.3% in the Tokai Hokuriku region, 22.3% in the Kinki region, 19.8% in the Chugoku region, 28.1% in the Shikoku region, and 25.3% in the Kyushu region. These regional differences were statistically significant. Moreover, MIH prevalence rates decreased with age. No significant sex differences in MIH prevalence rates were demonstrated. CONCLUSIONS: To our knowledge, this is the first MIH study carried out in several regions throughout Japan. Regional differences existed in MIH prevalence rates; particularly, MIH occurred more frequently in children residing in southwestern areas than those in northeastern areas of Japan.

Streptococcus pyogenes CAMP factor promotes calcium ion uptake in RAW264.7 cells.

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. It is known that S. pyogenes CAMP factor induces vacuolation in macrophages; however, the mechanism remains unclear. In the current study, the mechanism by which CAMP factor induces vacuolation in macrophages was investigated. CAMP factor was found to induce calcium ion uptake in murine macrophage RAW264.7 cells. In addition, EDTA inhibited calcium ion uptake and vacuolation in the cells. The L-type voltage-dependent calcium ion channel blockers nifedipine and verapamil reduced vacuolation. Furthermore, the phosphoinositide 3-kinase inhibitors LY294002 and wortmannin also inhibited the vacuolation induced by CAMP factor. Fluorescent microscopy revealed that clathrin localized to the vacuoles. These results suggest that the vacuolation is related to calcium ion uptake by RAW264.7 cells via L-type voltage-dependent calcium ion channels. Therefore, it was concluded that the vacuoles induced by S. pyogenes CAMP factor in macrophages are clathrin-dependent endosomes induced by activation of the phosphoinositide 3-kinase signaling pathway through calcium ion uptake.

An exploratory study of the factors related to mouth breathing syndrome in primary school children.

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. DESIGN: We surveyed 380 elementary school children from 6 to 12 years in age. The questionnaire consisted of 44 questions regarding their daily health conditions and lifestyle habits and was completed by the children's guardians. A factor analysis was performed to classify closely related questions into their respective factors and to examine the strength of the correlation between the newly revealed factors. RESULTS: Twenty-six out of the 44 questions were selected, and they were classified into seven factors. Factors 1-7 were defined as "Incompetent lip seal", "Diseases of the nose and throat", "Eating and drinking habits", "Bad breath", "Problems with swallowing and chewing", "Condition of teeth and gums", and "Dry lips", respectively. There were also correlations between these factors themselves. CONCLUSION: MBS was categorized according to 7 major factors. Because Factor 1 was defined as "Incompetent lip seal", which was representative of the physical appearance of mouth breathers and correlated with other factors, we suggested that MBS should consist of 7 factors in total.

Streptococcus pyogenes CAMP factor promotes bacterial adhesion and invasion in pharyngeal epithelial cells without serum via PI3K/Akt signaling pathway.

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. In this study, we identified a novel S. pyogenes adhesin/invasin. Our results revealed that CAMP factor promoted streptococcal adhesion and invasion in pharyngeal epithelial Detroit562 cells without serum. Recombinant CAMP factor initially localized on the membranes of cells and then became internalized in the cytosol following S. pyogenes infection. Additionally, CAMP factor phosphorylated phosphoinositide 3-kinase and serine-threonine kinase in the cells. ELISA results demonstrate that CAMP factor affected the amount of phosphorylated phosphoinositide 3-kinase and serine-threonine kinase in Detroit562 cells. Furthermore, CAMP factor did not reverse the effect of phosphoinositide 3-kinase knockdown by small interfering RNA in reducing the level of adhesion and invasion of S. pyogenes isogenic cfa-deficient mutant. These results suggested that S. pyogenes CAMP factor activated the phosphoinositide 3-kinase/serine-threonine kinase signaling pathway, promoting S. pyogenes invasion of Detroit562 cells without serum. Our findings suggested that CAMP factor played an important role on adhesion and invasion in pharyngeal epithelial cells.

Isolation and characterization of lymphoid enhancer factor-1-positive deciduous dental pulp stem-like cells after transfection with a piggyBac vector containing LEF1 promoter-driven selection markers.

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/ß-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). In this study, we attempted to isolate such LEF1-positive cells from human deciduous dental pulp cells (HDDPCs) by genetic engineering technology, using the human LEF1 promoter. DESIGN: A piggyBac transposon plasmid (pTA-LEN) was introduced into HDDPCs, using the Neon® transfection system. After G418 selection, the emerging colonies were assessed for EGFP-derived fluorescence by fluorescence microscopy. Reverse transcription polymerase chain reaction (RT-PCR) analysis was performed using RNA isolated from these colonies to examine stem cell-specific transcript expression. Osteoblastic or neuronal differentiation was induced by cultivating the LEF1-positive cells with differentiation-inducing medium. RESULTS: RT-PCR analysis confirmed the expression of several stem cell markers, including OCT3/4, SOX2, REX1, and NANOG, in LEF1-positive HDDPCs, which could be differentiated into osteoblasts and neuronal cells. CONCLUSIONS: The isolated LEF1-positive HDDPCs exhibited the properties of stem cells, suggesting that LEF1 might serve as a marker for SHED.

Tissue-Specific Stem Cells Obtained by Reprogramming of Non-Obese Diabetic (NOD) Mouse-Derived Pancreatic Cells Confer Insulin Production in Response to Glucose.

Type 1 diabetes occurs due to the autoimmune destruction of pancreatic ß-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. Previously, we demonstrated that insulin-producing cells could be produced by transfecting murine pancreatic cells with Yamanaka's reprogramming factors. Non-obese diabetic (NOD) mice are naturally occurring mutant mice defective in insulin production due to autoimmune ablation of pancreatic ß-cells. In this study, we showed that glucose-sensitive insulin-producing cells are successfully generated by transfecting primary pancreatic cells from NOD mice (aged 6 months old) with a plasmid harboring the cDNAs for Oct-3/4, Sox2, Klf4, and c-Myc. Transfection was repeated 4 times in a 2 day-interval. Sixty-five days after final transfection, cobblestone-like colonies appeared. They proliferated in vitro and expressed pluripotency-related genes as well as Pdx1, a transcription factor specific to tissue-specific stem cells for the ß-cell lineage. Transplantation of these cells into nude mice failed to produce teratoma unlike induced pluripotent stem cells (iPSCs). Induction of these cells to the pancreatic ß-cell lineage demonstrated their capability to produce insulin in response to glucose. These findings suggest that functional pancreatic ß-cells can be produced from patients with type 1 diabetes. We call these resultant cells as "induced tissue-specific stem cells from the pancreas" (iTS-P) that could be valuable sources of safe and effective materials for cell-based therapy in type 1 diabetes.

Streptococcus pyogenes CAMP factor attenuates phagocytic activity of RAW 264.7 cells.

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 ß-hemolysin. However, the effects of CAMP factor for immune cells are unclear. In this study, we investigated the effects of CAMP factor to macrophages. Western blotting analysis demonstrated that all examined strains expressed CAMP factor protein. In the presence of calcium or magnesium ion, CAMP factor was significantly released in the supernatant. In addition, both culture supernatant from S. pyogenes strain SSI-9 and recombinant CAMP factor dose-dependently induced vacuolation in RAW 264.7 cells, but the culture supernatant from Δcfa isogenic mutant strain did not. CAMP factor formed oligomers in RAW 264.7 cells in a time-dependent manner. CAMP factor suppressed cell proliferation via G2 phase cell cycle arrest without inducing cell death. Furthermore, CAMP factor reduced the uptake of S. pyogenes and phagocytic activity indicator by RAW 264.7 cells. These results suggest that CAMP factor works as a macrophage dysfunction factor. Therefore, we conclude that CAMP factor allows S. pyogenes to escape the host immune system, and contribute to the spread of streptococcal infection.

Choice of Feeders Is Important When First Establishing iPSCs Derived From Primarily Cultured Human Deciduous Tooth Dental Pulp Cells.

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). Primary cultures of HDDPCs were cotransfected with three plasmids containing human OCT3/4, SOX2/KLF4, or LMYC/LIN28 and pmaxGFP by using a novel electroporation method, and then cultured in an ESC qualified medium for 15 days. Emerging colonies were reseeded onto mitomycin C-treated MEFs or STO cells. The colonies were serially passaged for up to 26 passages. During this period, colony morphology was assessed to determine whether cells exhibited ESC-like morphology and alkaline phosphatase activity to evaluate the state of cellular reprogramming. HDDPCs maintained on MEFs were successfully reprogrammed into iPSCs, whereas those maintained on STO cells were not. Once established, the iPSCs were maintained on STO cells without loss of pluripotency. Our results indicate that MEFs are better feeder cells than STO cells for establishing iPSCs. Feeder choice is a key factor enabling efficient generation of iPSCs.

Analysis of tooth brushing cycles.

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. METHODS: Twenty healthy female dental hygienists participated in this study. Their tooth brushing motions were measured and analyzed using an American Dental Association-approved manual toothbrush to which a three-dimensional (3-D) accelerometer and strain tension gage were attached. 3-D motion and brushing force on the labial surface of the mandibular right central incisor and the lingual surface of the mandibular left first molar were measured, analyzed, and compared. Multilevel linear model analysis was applied to estimate variables and compare motion and forces related to the two tooth surfaces. RESULTS: The analysis of tooth brushing cycles was feasible, and significant differences were detected for durations and 3-D ranges of toothbrush motion as well as brushing force between the two tooth surfaces. CONCLUSION: The analysis used in this study demonstrated an ability to detect characteristics of tooth brushing motion, showing tooth brushing motion to change depending on the brushed location. These results also suggest that more detailed instructions might be required according to patient's oral condition.