157 research outputs found
Dental Approach for Obstructive Sleep Apnea
Obstructive sleep apnea (OSA) is characterized by intermittent upper airway obstruction during sleep. It causes sleep fragmentation from brief arousal and affects social life by excessive daytime sleepiness. Moreover, OSA is considered a risk factor for cardiovascular complications and type 2 diabetes as associated features. The gold standard treatment for OSA is continuous positive airway pressure during sleep. However, if this treatment is frustrating to the patient or the apnea and hypopnea index is low or mild, alternative treatments for OSA must be found. One possible treatment is an oral appliance (OA) to improve the upper airway configuration. Dental clinicians have attempted to improve this respiratory condition caused by OSA by using OA, and at Tokushima University Hospital, OA therapy has been in use since 1993. Nishigawa et al. introduced a method to fabricate an OA and to investigate the effects of this therapy. In the present article, the method of OA fabrication was modified, and its effects were evaluated. Dental clinicians should have some knowledge about the mechanics of sleep and the management of sleep conditions so that they can cooperate closely with medical physicians. Thus, collaboration between the medical and dental fields can help patients attain healthy sleep
Hard X-ray Properties of the Merging Cluster Abell 3667 as Observed with Suzaku
Wide-band Suzaku data on the merging cluster Abell 3667 were examined for
hard X-ray emission in excess to the known thermal component. Suzaku detected
X-ray signals in the wide energy band from 0.5 to 40 keV. The hard X-ray (> 10
keV) flux observed by the HXD around the cluster center cannot be explained by
a simple extension of the thermal emission with average temperature of ~7 keV.
The emission is most likely an emission from a very hot (kT > 13.2 keV) thermal
component around the cluster center, produced via a strong heating process in
the merger. In the north-west radio relic, no signature of non-thermal emission
was observed. Using the HXD, the overall upper-limit flux within a 34'x34'
field-of-view around the relic is derived to be 5.3e-12 erg s-1 cm-2 in the
10-40 keV band, after subtracting the ICM contribution estimated using the XIS
or the XMM-Newton spectra. Directly on the relic region, the upper limit is
further tightened by the XIS data to be less than 7.3e-13 erg s-1 cm-2, when
converted into the 10--40 keV band. The latter value suggest that the average
magnetic field within the relic is higher than 1.6 uG. The non-thermal pressure
due to magnetic fields and relativistic electrons may be as large as ~20% of
the thermal pressure in the region.Comment: 18 pages, 13 figures, to be appeared in PASJ 200
Frontal/Lateral Mandibular Translations-masticatory Movement Relationship
Objective: This study aimed to clarify whether crown restorations with adjusted occlusal surfaces that were formed using frontal/lateral mandibular translations, functioned without interference during mastication.
Materials and Methods: In 10 adult volunteers who had healthy normal dentition, frontal and lateral border movement was measured during unilateral mastication and free mastication, using an ultrasound digital mandibular measuring system (ARCUS digma2). Additionally, precise impressions of the upper and lower dental arch were taken, and dental casts were made. These casts were measured using a CAD/CAM scanning system (ARCTICA). For the fabrication of crown restorations, the functionally generated path technique (FGP technique) was used on the monitor for the lower first and second molar. The movement of the opposite teeth on the occlusal surface during frontal and lateral border movement, during unilateral mastication, and during free mastication was considered the functional occlusal surface. The data of the functional occlusal surface generated by frontal/lateral mandibular translations and that of each of the masticatory functional occlusal surfaces were superimposed using three-dimensional data evaluation software (GOM). The difference between these surfaces was evaluated to determine the interference area, maximum interference difference, and average interference difference.
Results: Interference was present for all functional occlusal surfaces created by mastication as well as those determined by frontal/lateral mandibular translations. The average interference values, in order of free masticatory movement, habitual masticatory side, and non-habitual masticatory side, were as follows. Interference area: 167.5±20.8 mm2, 121.9±28.5 mm2, 144.6±28.0 mm2; maximum interference distance: 345.0±43.1 μm, 189.0±39.9 μm, 309.0 ± 46.8 μm; average interference distance: 130.0±15.7 μm, 64.0±10.6 μm, 130.0±21.9 μm. Statistically significant differences were found for the maximum interference distance and average interference distance (both p<0.05).
Conclusions: The functional occlusal surfaces for each form of mastication demonstrated interference with the functional surface of frontal/lateral mandibular translations. Thus, crown restorations of which the occlusal surfaces were adjusted and formed by frontal/lateral mandibular translations may interfere with mastication
Relationships between thermic effect of food, insulin resistance and autonomic nervous activity
Background: The thermic effect of food (TEF) is higher in lean than in obese human subjects. Objective: Relationships between TEF and insulin resistance during meals, from the point of view of autonomic nervous activity, were evaluated. Methods : Autonomic nervous activity was evaluated in 20 young adults using the spectral analysis of heart rate variability from one hour before to two hours after a meal. Heart rate data were analyzed based on low frequency components (LF power, 0.04 - 0.15Hz),high frequency components (HF power, 0.15-0.40 Hz), and LF/HF ratios. Energy expenditure and the TEF were measured 30 min after a meal. Homeostasis model of insulin resistance index (HOMA-IR) was also measured. Results : The LF/HF ratio was significantly increased 30minafter a meal (p<0.05).No correlation between LF power and HF power with TEF was found, but the LF/HF ratio was significantly and positively correlated with TEF(r=+0.56,p<0.05). Moreover, a significant negative correlation was found between the HOMA-IR and TEF (r=-0.601, p<0.05). Conclusions : The findings suggest that a reduction in insulin sensitivity induces a poor response of sympathetic nervous activity in the postprandial phase and a reduction in postprandial energy expenditure
The somatic mutations in Interferon-γ signal molecules in human uterine leiomyosarcoma
Human uterine leiomyosarcoma (U-LMS) is neoplastic malignancy that typically arises in tissues of mesenchymal origin. The identification of novel molecular mechanism leading to human U-LMS formation and the establishment of new therapies has been hampered by several critical points. We earlier reported that mice with a homozygous deficiency for proteasome beta subunit 9 (Psmb9)/β1i, an interferon (IFN)-γ inducible factor, spontaneously develop U-LMS. The use of research findings of the experiment with mouse model has been successful in increasing our knowledge and understanding of how alterations, in relevant oncogenic, tumour suppressive, and signaling pathways directly impact sarcomagenesis. The IFN-γ pathway is important for control of tumour growth and invasion and has been implicated in several malignant tumours. In this study, experiments with human tissues revealed a defective expression of PSMB9/β1i in human U-LMS that was traced to the IFN-γ pathway and the specific effect of somatic mutations of JANUS KINASE (JAK) 1 molecule or promoter region on the locus cording PSMB9/β1i gene. Understanding the molecular mechanisms of human U-LMS may lead to identification of new diagnostic candidates or therapeutic targets against human U-LMS
Risk factors associated with soft coronary artery plaques in Japanese, as determined by 16 slice multidetector-row computed tomography
Purpose: The acute coronary syndrome is often caused by the rupture of plaques and thrombus formation even without significant stenosis, and patients with soft plaques, but without significant stenosis evidenced by coronary angiography(CAG), often develop an acute coronary syndrome. To address this discrepancy, a qualitative diagnosis of coronary plaques using a 16 slice multidetector-row CT was conducted.
Methods and Results: Volume rendering and cross-sectional MPR images were obtained. Based on the CT values, plaques on the coronary artery wall were classified as lipid-rich soft plaques(CT value50 HU) .
A significant correlation was observed between the percent stenosis determined in crosssectional MPR images and those determined by CAG(r=+0.92, p<0.01). Diffuse plaques with CT values of less than 50 HU often caused stenosis at level of 75% or less, which were not indicated by percutaneous transluminal coronary angioplasty.
Conclusions : Although diffuse soft plaques with CT values less than 50 HU are not an indication of intervention, a risk of an acute coronary syndrome exists, due to rupture. These soft plaques must be stabilized by treatment even when they do not cause significant stenosis, and MDCT is considered to be useful for their evaluation
Clearance of Aspergillus fumigatus is impaired in the airway in allergic inflammation
Background Aspergillus fumigatus (Af) sometimes colonizes and persists within the respiratory tree in some patients with asthma. To date, the precise reasons why the clearance of Af is impaired in patients with asthma remain unknown. Objective To characterize the effects of allergic airway inflammation on clearance of Af. Methods Control and Dermatophagoides farinae (Df) allergen-sensitized BALB/c mice were intranasally infected with Af. After 2 and 9 days of infection, the pathology, fungal burden, and cytokine profile in lung tissue were compared. In a different set of experiments, the phagocytotic activity of alveolar macrophages and the expression of their pathogen recognition receptors also were determined. Results The Af conidia and neutrophilic airway inflammation disappeared by day 9 after infection in control mice. In Df-sensitized mice, Af conidia and neutrophilic and eosinophilic airway inflammation persisted at day 9 after infection. Compared with control mice, Df allergen-sensitized mice showed significant increases in interleukin (IL)-5 and decreases in IL-12 and interferon-γ in lung tissues at day 2 after infection. Most importantly, compared with Af-infected non-Df-sensitized mice, IL-17 in lung tissues was significantly decreased in Df allergen-sensitized Af-infected mice at day 2 after infection but was significantly increased at day 9. Alveolar macrophages isolated from Df allergen-sensitized mice exhibited significant decreases in phagocytotic activity and expression of Toll-like receptor-4 and dectin-1 compared with those from control mice. Conclusion In the airway of patients with allergy, T-helper cell type 2-dominant immunity potentially affects the expression of pathogen recognition receptors and attenuates cellular defense against Af. Prolonged IL-17 production also could play an important role
The effect of G-CSF in a myocardial ischemia reperfusion model rat
Purpose : It has been reported that G-CSF administration improves cardiac function by reducing the area of the infarct in a myocardial infarction model rat. In the present study, myocardial infarction model rats, produced by ligation of the left anterior coronary artery, were prepared. The G-CSF effect for treating cardiac muscle cell disorders by ischemia reperfusion was studied. Methods : Myocardial infarction model rats were produced by ligation of the left anterior descending coronary artery in 12-week-old Wistar rats. G-CSF was administered subcutaneously daily at a dose of 100 μg/kg/day for 5 days to rats with a complete ligation (MI-G group, n=6) and rats in which the ligated coronary artery was reperfused 30 minutes after the ligation (R-G group, n=6). Physiological saline was subcutaneously administered to rats with a complete ligation and reperfusion (MI-C and R-C groups, respectively, n=6 each), as controls. After 4 weeks, the infarct area ratio (%), cardiac function on echocardiography (left ventricular ejection fraction), and a myocardial histopathological diagnosis were carried out and the results compared among the groups. Results : No significant differences were found in the proportion of the residual heart muscle in the infarct lesion, myocardial wall thickness, or left ventricular ejection fraction between the MI-G and MI-C groups. In contrast, the infarct area, myocardial wall thickness, and left ventricular ejection fraction were significantly improved in the R-G group compared to the R-C group (p<0.05). Conclusions : Any inhibitory effect of G-CSF on the infarct lesion was found in the myocardial infarction reperfusion model rat, but only a small effect was found in rats with a complete ligation-induced myocardial infarction. The findings in the present study, therefore, suggest that G-CSF is effective for treating cardiac muscle cell disorders by ischemia reperfusion
Burnout among kindergarten teachers and associated factors
Burnout among kindergarten teachers is a subject of great concern. Although burnout is reported to be significantly associated with turnover intention and work engagement, few studies have examined factors associated with burnout among these teachers. Therefore, in the present study, we performed a cross-sectional survey of burnout and associated factors among kindergarten teachers. We distributed 3363 questionnaires to all 205 authorized kindergartens and childcare institutions in Nagasaki Prefecture and received 1086 responses (response rate: 32.3%). The participants were limited to full-time female class teachers. After excluding survey forms with incomplete content, we ultimately examined valid responses from 442 participants. The survey examined burnout (Maslach Burnout Inventory, MBI), teacher stress (Nursery Teacher’s Stress Scale, NTSS), coping behaviors (Brief Scales for Coping Profile, BSCP), and social support (Social Support Scale, SSS). A multiple regression analysis revealed that all 3 MBI subscales were positively associated with “understanding of how to handle children” on the NTSS and negatively associated with “superiors” on the SSS. “Emotional exhaustion” was significantly associated with “interpersonal relations at work” and “lack of time” on the NTSS, and “avoidance and suppression” on the BSCP. “Depersonalization” was significantly associated with age, “disconnect in working conditions” on the NTSS, and “proactive problem solving” and “venting emotions to others” on the BSCP. “Diminished professional accomplishment” was significantly associated with age, “lack of time” on the NTSS, and “proactive problem solving” and “change in perspective” on the BSCP. These results suggest that support from superiors that enables teachers to better understand children and handle them appropriately is necessary to prevent burnout
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