The association between masticatory ability and lower Timed Up & Go Test performance among community-dwelling Japanese aging men and women: The Toon Health Study.

Objectives: Few studies examined the association between deterioration of masticatory ability assessed by objective marker and physical function. Therefore, we examined the association between salivary flow rate which is one of the objective and surrogate marker of masticatory ability and lower Timed Up & Go (TUG) performance which is one of major measurement of physical function among aging Japanese. Methods: This cross-sectional study enrolled 464 Japanese aged 60-84 years old. Participants chewed tasteless and odorless gum for 5 min, calculated stimulated salivary flow rate (g/min) during all chews. The 3 m TUG was conducted, and 75th percentile value (6.8 s for men and 7.0 s for women) or higher was defined as lower TUG performance. Logistic regression analysis was used to examine the association between stimulated salivary flow rate and lower TUG performance. Results: We found that the stimulated salivary flow rate tended to be negatively associated with the TUG time. We also observed significant negative association between stimulated salivary flow rate and lower TUG performance; the multivariable-adjusted OR (95% confidence interval, CIs) of lower TUG performance for the highest quartile of stimulated salivary flow rate compared with the lowest quartile was 0.34 (0.16-0.69, P for trend = 0.02). Further adjusting for BMI, the association was attenuated but remaind significant; the OR (95% CIs) in highest quartile was 0.37 (0.18-0.76, P for trend = 0.04). Conclusions: Higher stimulated salivary flow, which means well masticatory ability, was inversely associated with lower TUG performance in the aging Japanese population.

Effect of ensiled total mixed rations containing sake lees on digestion, nitrogen use, and plasma metabolite concentrations in sheep.

Sake lees are a byproduct of Japanese rice wine and used as ruminant feed with high protein and ethanol contents. This study aimed to explore the effects of ensiled total mixed ration (TMR) containing sake lees on rumen fermentation, digestion, nitrogen (N) use, and plasma metabolites in sheep. Four mature wethers were assigned to a 4 × 4 Latin square design with a factorial arrangement of ensiling treatment (non-ensiled or ensiled TMR) and types of sake lees (traditional or liquefied). Although dietary ethanol consumption was higher in sheep fed ensiled TMR, ruminal and plasma concentrations of methanol and ethanol increased after feeding in all dietary treatments, which was accompanied by the increased plasma concentrations of formate. The intake and digestion of dry matter and N were lower in sheep fed ensiled TMR than in those fed non-ensiled TMR. The plasma concentrations of most amino acids decreased in sheep fed ensiled TMR. Although plasma methionine, serine, and glycine concentrations were not altered by diet, homocysteine concentration was the highest in sheep fed ensiled TMR containing traditional sake lees. The negative impacts of ensiling treatment on N digestion and amino acid utilization should be considered for formulating ensiled TMR containing sake lees.

Salivary Alpha-Amylase Activity in Relation to Cardiometabolic Status in Japanese Adults without History of Cardiovascular Disease.

AIMS: Stress is known to be a potential contributor to the development of diabetes and hypertension. However, the biological mechanisms underlying the association between cardiometabolic risk markers and the biological stress response have not yet been determined. Therefore, we examined salivary alpha-amylase and heart rate variability in relation to cardiometabolic status in a sample of healthy Japanese men and women. METHODS: Participants (473 men and 1,029 women aged 30-84) underwent a 75 g oral glucose tolerance test after a 10-hr fast. The homeostasis model assessment index for insulin resistance was based on fasting and 2-hr postload glucose and insulin concentrations. Sitting blood pressure was measured twice after rest. A saliva sample was collected in the morning and salivary alpha-amylase was assayed. A 5-min heart rate variability recording was evaluated using time-domain indices of standard deviations of normal-to-normal intervals and root mean square of successive differences. Multivariate linear regression models were used to estimate associations between salivary alpha-amylase and each outcome measure. RESULTS: Salivary alpha-amylase was associated with fasting glucose (ß=0.008; 95% CI=0.002, 0.014), 2-hr postload glucose (ß=0.023; 95% CI=0.004, 0.041), homeostasis model assessment index for insulin resistance (ß=0.032; 95%CI=0.000, 0.064), systolic (ß=1.603; 95% CI=0.479, 2.726) and diastolic (ß=0.906; 95% CI=0.212, 1.600) blood pressures among women. These associations remained significant after further adjustment for heart rate variability measures. CONCLUSIONS: The elevation of salivary alpha-amylase may reflect a dysfunction of the sympathetic nervous system associated with cardiometabolic abnormalities in women.

Effect of non-surgical periodontal therapy on insulin resistance and insulin sensitivity among individuals with borderline diabetes: A randomized controlled trial.

OBJECTIVE: To investigate the effect of non-surgical periodontal therapy on insulin resistance and sensitivity among individuals with borderline diabetes not receiving medications. METHODS: A crossover, randomized controlled trial was conducted among participants with borderline diabetes diagnosed by a 75-g oral glucose tolerance test. Participants were randomly assigned to either an early or later intervention group. The early intervention group underwent non-surgical periodontal therapy of scaling and root planing during the first 6 months, followed by a 6-month non-intervention period. The order was reversed in the later intervention group. Primary outcomes included: fasting or post-load serum glucose and insulin, body mass index (BMI), HOMA-IR, HOMA-ß, and Matsuda Index. RESULTS: Seventy-four participants were randomized, and 71 participants completed the trial. There were no significant differences between groups in glucose and insulin concentrations during the intervention and non-intervention periods. When analyzed within groups by median-split of bleeding on probing (BOP) levels before intervention, the lower BOP group showed improved changes in BMI, HOMA-IR, HOMA-ß, and Matsuda Index (P < 0.05). Further, we observed a positive correlation between baseline BOP and change in BMI (P = 0.06). Change in BMI was positively correlated with changes in HbA1c, HOMA-IR, and HOMA-ß (P < 0.05), and inversely correlated with change in Matsuda Index (P = 0.001). CONCLUSIONS: Periodontal therapy had no significant effect on markers related to insulin and glucose metabolism among individuals with borderline diabetes. However, participants with a lower BOP (%) showed significant improvements in BMI, fasting serum insulin, HOMA-IR, HOMA-ß and Matsuda Index. CLINICAL SIGNIFICANCE: Among individuals diagnosed with borderline diabetes, those who had <37% of a lower BOP (%) showed potential improvements in BMI, fasting serum insulin, HOMA-IR, HOMA-ß and Matsuda Index following non-surgical periodontal therapy.

The impact of masticatory ability as evaluated by salivary flow rates on obesity in Japanese: The Toon health study.

OBJECTIVE: This study examined the associations of masticatory ability evaluated by chewing-gum-stimulated salivary flow rate with anthropometric indices among a general Japanese population. METHODS: In total, 921 Japanese men and women aged 30-79 years participated in this cross-sectional study. Saliva production was stimulated by 5 min of gum chewing, then collected; salivary flow rate was calculated as g/min. Overweight, abdominal obesity in terms of waist circumference (WC), and waist-hip ratio (WHR), and elevated skinfold thickness statuses were determined. RESULTS: The multivariable odds ratio and 95% confidence intervals of overweight, abdominal obesity (WC, WHR), and elevated skinfold thickness status for highest vs. lowest quartile of salivary flow rate were 0.59 (0.37-0.95, P for trend = 0.02), 0.65 (0.43-0.98, P = 0.03), 0.54 (0.35-0.83, P < 0.01), and 0.61 (0.39-0.96, P < 0.01), respectively. The linear trends of multivariable-adjusted means of BMI, WC, WHR, and skinfold thickness according to quartiles of salivary flow rate did not vary after stratification by overweight status. CONCLUSIONS: Higher stimulated salivary flow rate, a surrogate marker for mastication ability, was associated with lower prevalence of overweight, abdominal obesity (whether WC- or WHR-defined), and elevated skinfold thickness among the general Japanese population.

Role of macrophage migration inhibitory factor in otitis media with effusion in adults.

Otitis media with effusion (OME) is one of the most common ear diseases. Bacterial endotoxins and several inflammatory cytokines appear to be involved in the pathogenesis of OME in children; however, little is known of the immunological aspects of the onset of OME in adults. We sought to determine the presence of macrophage migration inhibitory factor (MIF) as well as interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), RANTES (regulated upon activation, normal T-cell expressed and presumably secreted), and endotoxin in middle ear effusions (MEEs) from adult patients with OME. In addition, the levels of MIF in MEEs from adults and children were compared. MEE was obtained from 95 adults and 11 children. The levels of MIF, IL-1beta, TNF-alpha, and RANTES were determined by enzyme-linked immunosorbent assay, and the concentrations of endotoxin and total protein were determined by the Endospec assay and bicinchoninic acid assay, respectively. MIF was detected in 97.9% of the MEEs from adults, while endotoxin, IL-1beta, TNF-alpha, and RANTES were detected in 96.8, 12.6, 5.3, and 43.9%, respectively. In addition, the level of MIF was significantly higher than those of endotoxin, IL-1beta, and TNF-alpha. A positive correlation between the levels of MIF and endotoxin was observed. MIF and endotoxin were detected in 81.8 and 72.7%, respectively, of the MEEs from the children. The level of MIF was significantly higher in the children, and conversely that of endotoxin was significantly higher in the adults. These results suggest that the interaction between MIF and endotoxin may promote fluid collection in the middle ear, particularly in adults.