The potential positive effect of periodontal treatment on brain function activity using functional magnetic resonance imaging analysis.

Background/purpose: There are reports on the relationship between periodontal treatment and the whole body. The purpose of the present study was to investigate the effect of periodontal initial treatment on brain function activity by improving periodontal tissue and the occlusal status of subjects with periodontitis. Materials and methods: The subjects were 13 patients with periodontitis. Following the patient's informed written consent, the periodontal initial treatment provided to the patient included tooth brushing instruction, scaling and root planning, however, occlusal adjustment was not performed at this stage. Periodontal examination, occlusal force examination and fMRI results were also evaluated at the initial and the reevaluation examinations. Results: After the periodontal initial treatment had been performed, periodontal tissue had significantly improved. In addition, cerebral blood flow in the insula and primary motor cortex was also improved, as confirmed by fMRI. Conclusion: This result suggests that the periodontal ligament has recovered and the periodontal ligament neuron have been further subjected to clenching in the insula.

Correlation of Salivary Occult Blood with the Plasma Concentration of Branched-Chain Amino Acids: A Cross-Sectional Study.

BACKGROUND: Plasma branched-chain amino acids (BCAA) levels are predictors of glycometabolic disorders, leading to diabetes. Microbes, including periodontal pathogens, are thought to be associated with elevated plasma BCAA levels. This study aimed to evaluate the relationship between salivary occult blood (SOB) and plasma BCAA levels in middle-aged Japanese individuals. METHODS: Sixty-four Japanese individuals aged ≥ 40 years were recruited for this study, which was conducted in Fukuoka Prefecture, Japan, from August to December 2021. Individuals diagnosed with and/or treated for diabetes were excluded from the study. The body mass index (BMI); plasma concentrations of total, high-density, and low-density lipoprotein cholesterol; triglyceride, glucose, and BCAA; and glycosylated hemoglobin ratio were measured. A basic periodontal examination was performed after the SOB test. RESULTS: The median age of participants (men-20; women-44) was 55 (range, 41-78) years. The plasma BCAA concentration in the SOB-positive group (477 [400-658] µmol/L) was higher than that in the SOB-negative group (432 [307-665] µmol/L). Linear regression analysis revealed that SOB remained independently associated with the plasma BCAA level with statistical significance (ß = 0.17, p = 0.02) after adjusting for sex, age, and BMI. CONCLUSIONS: SOB was positively correlated with plasma BCAA levels in middle-aged Japanese individuals. Thus, SOB may be a predictor of elevated plasma BCAA levels.

The Alteration of Brain Function by the Improvement of Periodontal Tissues and Occlusal State.

Objective: In this study, we have introduced a case in which the effective blood oxygenation level-dependent signal on functional magnetic resonance imaging (fMRI) was altered by the improvement of periodontal tissue and occlusal function in a patient with periodontitis Stage II Grade B. Material and Methods. A 61-year-old female patient requiring periodontal treatment was diagnosed as having periodontitis Stage II Grade B via clinical and radiographic examinations. Her past medical history included type 2 diabetes, hypertension, and hyperlipidemia. Following the patient's informed written consent, the periodontal initial treatment provided to the patient included tooth brushing instruction and scaling and root planing; however, occlusal adjustment was not performed at this stage. Occlusal force and fMRI results were also evaluated at the initial and reevaluation examinations. Results: After the periodontal initial treatment had been performed, it was noted that the patient's periodontal tissue and occlusal force had improved. It was also evident from fMRI that cerebral blood flow had been activated in the insula, primary motor cortex, and premotor cortex. Conclusion: This result suggested that the periodontal ligament had recovered and the periodontal ligament neuron had been further subjected to clenching in the insula so that the muscle spindle sensation impacted the motor cortex.

Swallowing dysfunction and the onset of fever in older residents with special care needs: a thirteen-month longitudinal prospective study.

A decline in swallowing function is frequently observed among older residents in nursing homes. We investigated whether swallowing dysfunction was related to the onset of fever in such individuals. Older residents aged ≥ 65 years from three nursing homes were included in this prospective study conducted from July 2017 to May 2019. The follow-up period was 13 months. The outcome was fever incidence in relation to the swallowing dysfunction. Baseline data on the activities of daily living, cognitive function, swallowing function, respiratory function, tongue pressure, and comorbidity conditions were collected. Dates on which the axillary temperature measured ay of participants was > 37.5 °C during the follow-up period were also recorded. For the statistical analyses, swallowing function assessed by the modified water swallow test (MWST) score was used to divide the participants into three groups: scores ≤ 3, 4, and 5. A total of 52 participants [median age, 89.5 years (67-104)] were enrolled. Kaplan-Meier analysis showed that the average periods until onset of fever in participants with MWST scores of ≤ 3, 4, and 5 were 8.0 (6.0-11.0), 10.0 (7.0-12.0), and 12.0 (10.0-13.0) months, respectively. Cox's proportional hazards regression model revealed that participants with an MWST score ≤ 3 were at a higher risk of fever than those with an MWST score of 5 (hazard ratio 11.5, 95% confidence interval 1.5-63.4, adjusted for possible confounders. The swallowing dysfunction correlated with the risk of fever in older residents of nursing homes.

Tongue cleaning maintains respiratory function in older individuals: A 1-year randomised controlled trial.

OBJECTIVE: The aim of this 1-year longitudinal randomised controlled trial was to evaluate the effectiveness of tongue cleaning on the maintenance of respiratory function in older adults requiring care. METHODS: The participants included 24 residents of two nursing homes in Kitakyushu, Japan. The participants were randomised to receive tongue cleaning with routine oral care (intervention group, n = 12), or routine oral care alone (control group, n = 12). Among the participants, three in the intervention group and four in the control group had cerebrovascular disease history, four in the intervention group and four in the control group had a history of cardiac disease, and five in the intervention group and four in the control group were without medical history. Respiratory function was assessed on the basis of the peak expiratory flow rate (PEFR). Tongue pressure, swallowing function, oral health status, activities of daily living and nutritional status were also measured at baseline and at the end of the 1-year follow-up period. RESULTS: The number of analysed participants in each group was 12. In the control group, the PEFR (1.6 [0.4-4.2] L s-1 vs 1.4 [0.4-3.2] L s-1 , P = .034) and tongue pressure (16.4 [1.7-35.2] kPa vs 8.0 [1.4-38.6] kPa, P = .032) significantly declined after 1-year. However, the PEFR (1.5 [0.8-2.9] L s-1 vs 1.6 [0.7-4.2] L s-1 , P = .366) and tongue pressure (18.1 [4.2-37.1] kPa vs 16.1 [5.2-41] kPa, P = .307) were maintained in the intervention group. The change in the PEFR was significantly greater in the intervention group compared with the control group (0.130 [-0.45-1.70] L s-1 vs -1.70 [-10.00-10.00] L s-1 , P = .028). CONCLUSION: Our findings suggest that tongue cleaning may help maintain tongue and respiratory function in older adults requiring care.

Macrophage-mediated repair of intraepithelial damage in rat oral mucosa.

OBJECTIVE: It is important to protect the patient's oral mucosa from injury caused by inappropriate oral care. We established anin vivo model of intraepithelial injury of the oral mucosa and assessed the effects of inappropriate dental apparatus use on inflammatory response of macrophages in rats. DESIGN: Using this model, swabbing was performed to the labial mucosa of rats with the interdental brush, and the tissue samples were processed for histological evaluation. RESULTS: CD 68-positive macrophage-like cells appeared only in the subepithelial region after intraepithelial injury in the presence and absence of antibiotics. After intraepithelial injury, interleukin-1ß levels did not increase beyond those observed in intact rats. The number of bacteria in the lip increased slightly and decreased promptly. In the ear, intraepithelial injury caused an inflammatory response with macrophages infiltrating into the intraepithelial region as well as the subepithelial region, increased interleukin-1ß production, and high bacterial levels around tissues. CONCLUSION: Our results highlight the importance of protecting against the intraepithelial injury during oral care procedures, and these findings would contribute to oral care risk management in the future.

Statin inhibits the expression of secretory phospholipase A2 and subsequent monocyte chemoattractant protein-1 in human endothelial cells.

Phospholipase A2 (PLA2) changes the phosphatidylcholine contained in low-density lipoprotein (LDL) to lysophosphatidylcholine (LPC), which has various proatherogenic properties. We reported that tumor necrosis factor-alpha (TNFα) enhanced the expression of group V PLA2 (sPLA2-V) in human umbilical vein endothelial cells (HUVECs), and the LPC content in LDL and the monocyte chemoattractant protein-1 (MCP-1) expression were augmented when TNFα-stimulated HUVECs were incubated with LDL. Here, we observed that an HMG-CoA reductase inhibitor, pitavastatin, at the concentration of >1 µM administered 12 hours before TNFα stimulation suppressed the enhancement of sPLA2-V mRNA and protein. Pitavastatin also prevented the enhancement of the LPC content in LDL and the expression of MCP-1 mRNA when TNFα-stimulated HUVECs were incubated with LDL. The administration of geranylgeranyl pyrophosphate restored the expression of sPLA2-V mRNA and protein. The administration of the Rho kinase inhibitor Y-27632 and the transfection of small interfering RNA (siRNA) against sPLA2-V before TNFα stimulation both diminished the TNFα-induced sPLA2-V mRNA expression. Therefore, Y-27632 and siRNA against sPLA2-V also prevented the enhancement of MCP-1 mRNA expression when TNFα-stimulated HUVECs were incubated with LDL. Pitavastatin's inhibitory effect on the expression of sPLA2-V induced by TNFα may be useful to prevent the proatherogenic modification of LDL.

Cognitive function and 10 year mortality in an 85 year-old community-dwelling population.

The relationship between mortality and impaired cognitive function has not been thoroughly investigated in a very elderly community-dwelling population, and little is known about the association of disease-specific mortality with Mini-Mental State Examination (MMSE) subscale scores. Here we evaluated these data in Japanese community-dwelling elderly. In 2003, 85 year-olds (n=207) were enrolled; 205 completed the MMSE for cognitive function and were followed-up for 10 years, during which time 120 participants died, 70 survived, and 17 were lost to follow-up. Thirty-eight deaths were due to cardiovascular disease, 22 to senility, 21 to respiratory disease, and 16 to cancer. All-cause mortality decreased by 4.3% with a 1-point increase in the global MMSE score without adjustment, and it decreased by 6.3% with adjustment for both sex and length of education. Cardiovascular mortality decreased by 7.6% and senility mortality decreased by 9.2% with a 1-point increase in the global MMSE score with adjustment for sex and education. No association was found between respiratory diseases or cancer mortality and global MMSE score. All-cause mortality also decreased with increases in MMSE subscale scores for time orientation, place orientation, delayed recall, naming objects, and listening and obeying. Cardiovascular mortality was also associated with the MMSE subscale of naming objects, and senility mortality was associated with the subscales of time orientation and place orientation. Thus, we found that impaired cognitive function determined by global MMSE score and some MMSE subscale scores were independent predictors of all-cause mortality or mortality due to cardiovascular disease or senility in 85 year-olds.

Serum total cholesterol concentration and 10-year mortality in an 85-year-old population.

Little is known about the association between total cholesterol (TC) and all-cause mortality in the elderly (especially the very elderly). Here we examined the association between TC and all-cause mortality in 207 very elderly (85-year-old) participants. In 2003, we performed a baseline laboratory blood examination, and blood pressure (BP) and body mass index (BMI) measurements, and lifestyle questionnaires were completed by the participants. The participants were followed for the subsequent 10 years. As of 2013, of the 207 participants in 2003, 70 participants had survived, 120 individuals had died, and 17 were lost to follow up. The TC values were divided into high-TC (≥209 mg/dL), intermediate-TC (176-208 mg/dL), and low-TC (≤175 mg/dL) categories. With the Kaplan-Meier method, we found that both the high-TC and intermediate-TC participants survived longer than the low-TC participants. The men with high TC survived longer than those with low TC, but no corresponding difference was found for the women. A multivariate Cox proportional hazards regression model, with adjustment for gender, smoking, alcohol intake, history of stroke or heart disease, serum albumin concentration, BMI, and systolic BP, revealed that the total mortality in the low-TC group was 1.7-fold higher than that in the high-TC group. Mortality, adjusted for the same factors, decreased 0.9% with each 1 mg/dL increase in the serum TC concentration and decreased 0.8% with each 1 mg/dL increase in the serum (low-density lipoprotein) LDL-cholesterol (LDL-C) concentration. Our results indicate an association between lower serum TC concentrations and increased all-cause mortality in a community-dwelling, very elderly population. Mortality decreased with the increases in both TC and LDL-C concentrations, after adjustment for various confounding factors. These findings suggest that low TC and low LDL-C may be independent predictors of high mortality in the very elderly.

High-level activities of daily living and disease-specific mortality during a 12-year follow-up of an octogenarian population.

BACKGROUND: Little is known about the relationship between disease-specific mortality and high-level activities of daily living in the elderly. We examined whether mortality is associated with high-level activities of daily living in an octogenarian population. METHODS: We conducted a population-based cross-sectional and prospective cohort study in 693 older persons aged 80 years and living in Japan's Fukuoka Prefecture. We then evaluated the association between 12-year disease-specific mortality and high-level functional capacity as measured by the Tokyo Metropolitan Institute of Gerontology Index of Competence, which is a standardized multidimensional 13-item instrument; items 1 through 5 are classified as instrumental self-maintenance activity, items 6 through 9 as intellectual activity, items 10 through 13 as social roles activity, and all 13 items together yield total functional capacity. RESULTS: By the 12-year follow-up of the 693 participants, 413 had died, 242 survived, and 38 were unable to be located. Of the 413 who died, 105 died of cardiovascular disease, 73 of respiratory tract disease, 71 of cancer, and 39 of senility. Of the other 125 deaths, 59 were due to other diseases, and the cause of death for 66 participants is not known. The hazard ratio (HR) for all-cause mortality, adjusted for confounding factors with multivariate Cox analyses, fell by 6% (HR 0.937, 95% confidence interval [CI] 0.899-0.978, P = 0.003) with each one-point increase in participants' scores on the Tokyo Metropolitan Institute of Gerontology Index of total functional capacity. With one-point increases in instrumental self-maintenance activity and in intellectual activity, the HRs for all-cause mortality decreased by 14% (HR 0.856, 95% CI 0.787-0.930, P = 0.000) and 12% (HR 0.884, 95% CI 0.794-0.983, P = 0.023), respectively. Respiratory mortality with HR adjustment fell by 11% (HR 0.887, 95% CI 0.804-0.978, P = 0.016) and 24% (HR 0.760, 95% CI 0.627-0.922, P = 0.005) with one-point increases in the scores of total functional capacity and instrumental self-maintenance activity, respectively. Similarly, mortality due to senility fell by 16% (HR 0.838, 95% CI 0.743-0.946, P = 0.004), 29% (HR 0.707, 95% CI 0.564-0.886, P = 0.003), and 29% (HR 0.710, 95% CI 0.522-0.966, P = 0.029) with one-point increases in the scores of total functional capacity, instrumental self-maintenance activity, and intellectual activity, respectively. CONCLUSION: These findings suggest that high-level activities of daily living may be an independent predictor of mortality due to all causes, respiratory disease and senility in older persons.

Activities of daily living dependency and disease-specific mortality during 12-year follow-up in an 80-year-old population.

BACKGROUND AND AIMS: Although total mortality is likely to be higher in elderly individuals with frailty or impaired activities of daily living (ADL), little is known about the relationships between disease-specific mortality and ADL dependency in the elderly. Therefore, we examined whether 12-year disease-specific mortality may be associated with ADL dependency in an 80-year-old population. METHODS: In 1998, of 1,282 community-dwelling residents of Japan's Fukuoka Prefecture, 824 (64.3 %) (309 males and 515 females) participated, the remaining 458 subjects did not participate, and their deaths and causes of death were followed up for 12 years after the baseline examination. ADL dependency was determined according to the guidelines for disabled elderly from the Health, Labor, and Welfare Ministry of Japan, and ADL dependency was measured only at baseline. RESULTS: During the 12-year follow-up, 506 died, 276 did not die, and 42 were lost. Of the 506 who died, 128 died due to cardiovascular disease, 96 to respiratory tract disease, 87 to cancer, and 51 to senility. The subjects were classified into three groups as follows: ADL-1 (independent group, n = 600), ADL-2 (almost-independent group, n = 113), and ADL-3 (dependent group, n = 93).Total-cause mortality was 2.8 times higher in ADL-3 subjects, respiratory disease mortality was 4.1 times higher in ADL-3 subjects, and senility mortality was 5.7 times higher in ADL-3 subjects than in ADL-1 subjects, after adjusting for various confounding factors. There was no association between mortality due to cancer or cardiovascular disease and ADL dependency. CONCLUSIONS: We found an independent association between ADL dependency and mortality due to all causes, respiratory disease or senility, but no association with mortality due to cancer or cardiovascular disease. These findings suggest that improving ADL dependency may reduce all mortality and mortality due to respiratory disease or senility.

Body mass index and disease-specific mortality in an 80-year-old population at the 12-year follow-up.

Although many investigations examined the relationship between body mass index (BMI) and mortality, little is known about the possible associations between BMI and disease-specific mortality in very elderly people. Here we evaluated this association in an 80-year-old population. In 1998, 675 residents in Japan's Fukuoka Prefecture participated. They were followed up for 12 years after the baseline examination; 37 subjects (5.5%) were lost to follow-up. The subjects were divided into six groups by their BMI values: <19.5 (most-thin), 19.5 to <21.1 (relatively thin), 21.1 to <22.5 (thin/normal), 22.5 to <23.8 (normal/overweight), 23.8 to <26.0 (relatively obese), ≥26.0 (most-obese). The most-thin group had the highest mortality from all-causes, and from respiratory disease. The normal/overweight group had the lowest overall mortality among the six BMI groups. These associations were found in the men, but not in the women. The most-obese group did not have higher mortality from all-causes or cardiovascular disease compared to the normal/overweight group. Respiratory disease-related mortality was lowest in the most-obese group. No association was found between BMI group and mortality from cancer. In conclusion, in an 80-year-old Japanese population, mortality from all-causes or respiratory disease was highest in the most-lean group (BMI <19.5), and mortality from all-causes or cardiovascular disease was lowest in the group with BMI 22.5 to <23.8.

Oral health in patients on haemodialysis for diabetic nephropathy and chronic glomerulonephritis.

OBJECTIVE: The objective of this study was to clarify differences in oral health status between patients who needed haemodialysis (HD) owing to diabetic nephropathy (DN) and chronic glomerulonephritis (CGN). MATERIALS AND METHODS: Ninety-eight HD patients who were 50-70 years old were selected as the study subjects [DN group (29 subjects) and CGN group (69 subjects)] to compare with 106 control subjects (control group) not undergoing HD. All HD subjects underwent oral- and systemic-related examination just before HD therapy. RESULTS: The mean number of teeth present in the DN group was significantly less than in the CGN and control groups. The mean percentage of sites with bleeding on probing in the DN group was greater than in the CGN and control groups. The mean salivary flow rate in the DN and CGN groups was significantly lower compared with the control group. CONCLUSION: The patients undergoing HD for DN were found to have fewer teeth and worse periodontal health compared with those undergoing HD for CGN and with the control subjects not undergoing HD. Furthermore, the dental and periodontal health of the patients undergoing HD for CGN was comparable to that of the controls. CLINICAL RELEVANCE: For effective measures of prevention and improvement of oral health in HD patients, clinicians should be aware of the differences in the characteristics of the oral health between patients undergoing HD for DN and CGN.

Effects of thirty-times chewing per bite on secretion of glucagon-like peptide-1 in healthy volunteers and type 2 diabetic patients.

Glucagon-like peptide 1 (GLP-1) is secreted from the small intestine to the blood in response to glucose intake during a meal; however, it is not known whether mastication affects GLP-1 secretion. Here, we examined the relationship between mastication and GLP-1 secretion, along with postprandial blood glucose and insulin concentrations. We compared the levels of blood glucose, serum insulin, and plasma active GLP-1 concentrations after young healthy volunteers ate a test meal either by usual eating (control) or in one of three specified ways: 1. unilateral chewing, 2. quick eating, 3. 30-times chewing per bite. Ten volunteers participated in each of the three groups. Plasma active GLP-1 concentrations did not change by unilateral chewing or quick eating, but did increase by the third method, without affecting the concentrations of blood glucose or serum insulin. Next, we tested whether 30-times chewing per bite increased plasma active GLP-1 concentrations in 15 patients with type 2 diabetes mellitus, but there was no difference in results between usual eating and 30-times chewing per bite. This is a pilot trial with a small number of subjects, but is the first study to investigate the relationships between various styles of mastication and the GLP-1 secretion in young healthy volunteers and type 2 diabetic patients.

Telmisartan and N-acetylcysteine suppress group V secretory phospholipase A2 expression in TNFα-stimulated human endothelial cells and reduce associated atherogenicity.

Group V secretory phospholipase A2 (sPLA2-V) hydrolyzes phosphatidylcholine in low-density lipoprotein (LDL) to increase lysophosphatidylcholine (LPC) content. Because in human umbilical vein endothelial cells (HUVEC), tumor necrosis factor alpha (TNFα)-induced sPLA2-V expression, and LPC content in LDL and monocyte chemoattractant protein-1 mRNA were enhanced by incubation of LDL with TNFα-stimulated HUVEC, we investigated whether an angiotensin II receptor type 1 blocker, telmisartan, or an antioxidant drug, N-acetylcysteine (NAC), suppressed TNFα-induced sPLA2-V expression. Telmisartan or NAC administered before and during TNFα stimulation diminished the increase of sPLA2-V mRNA in HUVEC and reduced TNFα-induced sPLA2-V protein at 3 days after TNFα stimulation. Angiotensin II did not induce sPLA2-V mRNA, and a peroxisome proliferator-activated receptor-γ antagonist, GW3335, did not influence the inhibitory effect of telmisartan on TNFα-induced sPLA2-V mRNA. At 3 days after TNFα stimulation, 30 µM telmisartan or 20 mM NAC administered before and during TNFα stimulation prevented the enhancement of LPC content in LDL and monocyte chemoattractant protein-1 mRNA by LDL incubation with TNFα-stimulated HUVEC. A 2-month treatment with telmisartan in 29 hypertensive type 2 diabetic patients significantly reduced LPC content in circulating LDL. Telmisartan's suppressive effect on TNFα-induced sPLA2-V expression may have beneficial effects in preventing proatherogenic changes of LDL.

Physical fitness and 6.5-year mortality in an 85-year-old community-dwelling population.

Although poor physical fitness is known to be associated with increased mortality in adult and elderly populations, this association is not conclusive in very elderly. The purpose of the present study was to evaluate the association for a very old community-dwelling population. The participants (90 males, 117 females) were 85-year-old individuals residing in Fukuoka, Japan. Baseline examinations including muscle strength of the handgrip and leg extension, one-leg standing, leg stepping rate, and walking were performed in 2003 and these subjects were followed for 6.5 years. During the follow-up period, 81 individuals (49 males and 32 females) died. Handgrip strength and leg extension strength at age 85 were stronger in surviving men than in non-survivors. Total mortality adjusted for both gender and serum level of total cholesterol fell 5-6% with a 1-kg increase in the handgrip strength of a single hand or both hands. Total mortality also decreased 2% with a 1 kg increase in the leg extension strength of both legs. With adjustment for gender and total cholesterol, mortality fell by 57% in participants of the walking test and fell by 45% in participants of the stepping-rate test compared to mortality in nonparticipants. No association was found between mortality and participation in the handgrip strength test, leg extension strength test, or one-leg standing time test. In conclusion, not only poor muscle strength in handgrip or leg extension, but also nonparticipation in walking test or leg-stepping test were independent predictors of total mortality in a very elderly population.

Correlations between health status and OralChroma™-determined volatile sulfide levels in mouth air of the elderly.

Dimethyl sulfide (DMS), a volatile sulfur compound (VSC) found in mouth air, is thought to be associated with systemic diseases; this in contrast to the two other VSCs found in mouth air: hydrogen sulfide and methyl mercaptan (MM). This study aimed to validate the relationship between DMS in mouth air and oral and systemic factors. The subjects were 393 elderly Japanese volunteers participating in an oral and systemic health survey. They were surveyed for the concentration of VSC components in their mouth air and for their oral and systemic health status. Using logistic regression models, the prevalence of DMS in mouth air above the organoleptic threshold level (OTL) was found to be significantly associated with high-density lipoprotein (HDL) cholesterol level, medical history of colon polyps and asthma, being female, and the presence of MM in mouth air above the OTL. Our data suggest that systemic factors, such as a high serum HDL cholesterol level and a medical history of asthma and colon polyps, might be more prominent in subjects with elevated DMS. The differences, although statistically significant, are quite small. They also indicate that an oral factor, such as a high MM mouth-air level also influences the DMS mouth-air level in addition to systemic factors.

Perspectives on a new educational system for dental hygiene students in Japan.

The purpose of this article is to report changes to dental hygiene education in Japan and to evaluate the successful implementation of these changes in 2010. The legislative change that began in 2005 revised the length of education for dental hygiene students from two years to three or four years (the mandate was three years), which has led to a dramatic change in program curriculum. After a five-year moratorium, a new curriculum has been established for dental hygiene education in Japan. The new curriculum provides students the requisite knowledge to effectively perform the latest dental hygiene procedures. Although the change of the educational system from the present mandatory three-year to the new four-year programs poses many administrative problems, we believe this shift will ultimately provide a more thorough and in-depth education for students.

Expression of secretory phospholipase A 2 in insulitis of human transplanted pancreas and its insulinotropic effect on isolated rat islets.

The expression of secretory phospholipase A 2 (sPLA 2) is induced by inflammatory stimuli in various cells, and sPLA 2 contribute to produce proinflammatory lipid mediators via hydrolyzing plasma membrane phospholipids into free fatty acid and lysophospholipid. We studied the expression of group IIA sPLA 2 in human islets of transplanted pancreas before and after the recurrence of type 1 diabetes mellitus in a case study. In addition, the effects of exogenous sPLA 2 in isolated rat islets were investigated. Expression of group IIA sPLAs was immunohistochemicaly investigated in the pancreas graft biopsy specimens. Insulin secretion was evaluated by static incubation with different concentrations of snake venom sPLA 2. Intracellular free Ca ( 2) + concentration was measured with Fura 2 and lysophosphatidylcholine (LPC) contents in islets were determined by electrospray ionization-liquid chromatography/mass spectrometry. Group IIA sPLA 2 was not expressed in islets without insulitis before the recurrence, whereas it was diffusely expressed in islets after the recurrence with insulitis. There were cells co-expressing group IIA sPLA 2 and insulin. sPLA 2 dose-dependently induced insulin secretion in isolated rat islets, which was completely prevented by a specific sPLA 2 inhibitor indoxam. The application of sPLA 2 did not affect intracellular free Ca ( 2) + concentration in ß cells. On the other hand, LPC contents in islets were significantly increased in sPLA 2-treated islets compared with untreated islets. Incubation with indoxam suppressed the sPLA 2-induced increase of LPC. In conclusion, the present study suggests that group IIA sPLA 2 may be expressed in islets during insulitis in humans. Although sPLA 2 induced insulin secretion in vitro probably via the production of lysophospholipid, the significance of this enzyme expression in insulitis remains elusive.

Relationship between tooth loss and mortality in 80-year-old Japanese community-dwelling subjects.

BACKGROUND: Findings from several studies suggest associations between tooth loss and health outcomes, including malnutrition, poor quality of life, and mortality, in older individuals. However, limited information is available regarding whether those associations remain true in very elderly subjects after adequately considering confounding factors such as sex and smoking status. Herein, we determined whether the number of teeth in 80-year-old subjects is an independent predictor of mortality. METHODS: We initially contacted 1282 80-year-old community-dwelling individuals born in 1917, of whom 697 responded and participated in a baseline study, with follow-up examinations conducted 4 and 5.5 years later. Data from interviews and medical and oral examinations were obtained, and oral health was determined according to the number of teeth remaining in the oral cavity. RESULTS: A total of 108 and 157 subjects died in 4 years and 5.5 years, respectively, after the baseline study. Tooth loss was significantly associated with mortality at age 85.5, but not at age 84, after adjusting for potential confounders. When the analysis was stratified by sex, we found a stronger association in females in follow-up examinations conducted at both 4- and 5.5 years. On the other hand, the effect of tooth loss on mortality was not significantly different between smokers and non-smokers. CONCLUSION: Tooth loss is a significant predictor of mortality independent of health factors, socio-economic status, and lifestyle in octogenarians, with a stronger association in females.