27 research outputs found
The Tokyo Oldest Old Survey on Total Health (TOOTH): A longitudinal cohort study of multidimensional components of health and well-being
<p>Abstract</p> <p>Background</p> <p>With the rapid worldwide increase in the oldest old population, considerable concern has arisen about the social and economic burden of diseases and disability in this age group. Understanding of multidimensional structure of health and its life-course trajectory is an essential prerequisite for effective health care delivery. Therefore, we organized an interdisciplinary research team consisting of geriatricians, dentists, psychologists, sociologists, and epidemiologists to conduct a longitudinal observational study.</p> <p>Methods/Design</p> <p>For the Tokyo Oldest Old Survey on Total Health (TOOTH) study, a random sample of inhabitants of the city of Tokyo, aged 85 years or older, was drawn from the basic city registry. The baseline comprehensive assessment consists of an in-home interview, a self-administered questionnaire, and a medical/dental examination. To perform a wide variety of biomedical measurements, including carotid ultrasonography and a detailed dental examination, participants were invited to our study center at Keio University Hospital. For those who were not able to visit the study center, we provided the option of a home-based examination, in which participants were simultaneously visited by a geriatrician and a dentist. Of 2875 eligible individuals, a total of 1152 people were recruited, of which 542 completed both the in-home interview and the medical/dental examination, with 442 completed the in-home interview only, and another 168 completed self or proxy-administered data collection only. Carotid ultrasonography was completed in 458 subjects, which was 99.6% of the clinic visitors (n = 460). Masticatory assessment using a colour-changeable chewing gum was completed in 421 subjects, a 91.5% of the clinic visitors.</p> <p>Discussion</p> <p>Our results demonstrated the feasibility of a new comprehensive study that incorporated non-invasive measurements of subclinical diseases and a detailed dental examination aiming at community-dwelling individuals aged 85 years or older. The bimodal recruitment strategy is critically important to capture a broad range of health profiles among the oldest old. Results form the TOOTH study will help develop new models of health promotion, which are expected to contribute to an improvement in lifelong health and well-being.</p> <p>Trial Registration</p> <p>This study has been registered in the UMIN-Clinical Trial Registry (CTR), ID: UMIN000001842.</p
Human mandibular shape is associated with masticatory muscle force
Understanding how and to what extent forces applied to the mandible by the masticatory muscles influence its form, is of considerable importance from clinical, anthropological and evolutionary perspectives. This study investigates these questions. Head CT scans of 382 adults were utilized to measure masseter and temporalis muscle cross-sectional areas (CSA) as a surrogate for muscle force, and 17 mandibular anthropometric measurements. Sixty-two mandibles of young individuals (20-40 years) whose scans were without artefacts (e.g., due to tooth filling) were segmented and landmarked for geometric morphometric analysis. The association between shape and muscle CSA (controlled for size) was assessed using two-block partial least squares analysis. Correlations were computed between mandibular variables and muscle CSAs (all controlled for size). A significant association was found between mandibular shape and muscle CSAs, i.e. larger CSAs are associated with a wider more trapezoidal ramus, more massive coronoid, more rectangular body and a more curved basal arch. Linear measurements yielded low correlations with muscle CSAs. In conclusion, this study demonstrates an association between mandibular muscle force and mandibular shape, which is not as readily identified from linear measurements. Retrodiction of masticatory muscle force and so of mandibular loading is therefore best based on overall mandibular shape
Association between maximum occlusal force and 3-year all-cause mortality in community-dwelling elderly people
Role of GABA(A) receptors in the retrorubral field and ventral pallidum in rat jaw movements elicited by dopaminergic stimulation of the nucleus accumbens shell.
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48513.pdf (publisher's version ) (Closed access)The role of gamma-aminobutyric acid (GABA)(A) receptors in the retrorubral field in the production of rat repetitive jaw movements was examined, as this nucleus receives a GABAergic, inhibitory input from the nucleus accumbens and is connected with the parvicellular reticular formation, a region that is directly connected with the orofacial motor nuclei. The GABA(A) receptor antagonist bicuculline (150 ng/0.2 microl per side) significantly produced repetitive jaw movements when injected bilaterally into the retrorubral field, but not the ventral pallidum. The effects of bicuculline were GABA(A) receptor specific, because the effects were abolished by muscimol, a GABA(A) receptor agonist, given into the same site. The bicuculline-induced jaw movements differed qualitatively from those elicited by injection of a mixture of (+/-)-6-chloro-7,8-dihydroxy-3-allyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benz azepine-7,8-diol (SKF 82958; 5 microg) and quinpirole (10 microg), agonist at dopamine D1 and D2 receptors respectively, into the nucleus accumbens shell. Nevertheless, bilateral injections of muscimol (10 ng, 25 ng and 50 ng/0.2 microl per side) into the retrorubral field significantly inhibited jaw movements evoked by the dopamine D1/D2 receptor stimulation in the nucleus accumbens shell. Bilateral injections of bicuculline (50 ng and 150 ng/0.2 microl per side) also reduced the dopamine D1/D2 receptor-mediated jaw movements. Essentially similar effects were obtained when muscimol and bicuculline were given into the ventral pallidum, a region that is also known to receive GABAergic inhibitory inputs from the nucleus accumbens. In conclusion, GABA(A) receptor blockade in the retrorubral field elicits characteristic repetitive jaw movements, and the GABA(A) receptors in that region as well as in the ventral pallidum modulate the accumbens-specific, dopamine D1/D2 receptor-mediated jaw movements
Role of GABA B receptors in the endomorphin-1-, but not endomorphin-2-, induced dopamine efflux in the nucleus accumbens of freely moving rats.
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71132.pdf (publisher's version ) (Closed access)In vivo microdialysis was used to study the effects of the locally applied GABA B receptor antagonist 2-hydroxysaclofen and GABA B receptor agonist baclofen on the basal dopamine efflux as well as on the endomorphin-1- and endomorphin-2-induced dopamine efflux in the nucleus accumbens of freely moving rats. 2-Hydroxysaclofen (100 and 500 nmol) increased basal dopamine efflux. Baclofen (2.5 and 5 nmol) failed to affect basal dopamine efflux. 2-Hydroxysaclofen (1 and 10 nmol) which did not alter the basal dopamine efflux, enhanced the endomorphin-1 (25 nmol)-induced dopamine efflux. Baclofen (2.5 and 5 nmol) failed to affect endomorphin-1 (25 nmol)-induced dopamine efflux, but it counteracted the 2-hydroxysaclofen-induced increase of the endomorphin-1-elicited dopamine efflux. Neither 2-hydroxysaclofen (10 nmol) nor baclofen (5 nmol) affected the endomorphin-2 (25 nmol)-induced dopamine efflux. The doses mentioned are the total amount of drug over the infusion period that varied across the drugs (25 or 50 min). These results suggest that accumbal GABA B receptor plays an inhibitory role on the basal as well as the endomorphin-1-elicited accumbal dopamine efflux. The present results support our earlier reported notion that endomorphin-1 and endomorphin-2 increase accumbal dopamine efflux by different mechanisms. Finally, it is suggested that a decrease of endogenous accumbal GABA reduces the accumbal GABA B receptor-mediated GABA-ergic inhibition, enhancing thereby the accumbal dopamine efflux
Role of GABAA receptors in the endomorphin-1-, but not endomorphin-2-, induced dopamine efflux in the nucleus accumbens of freely moving rats.
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71133.pdf (publisher's version ) (Closed access)In vivo microdialysis was used to study the effects of the locally applied GABA(A) receptor agonist muscimol and GABA(A) receptor antagonist bicuculline on the basal dopamine efflux as well as on the endomorphin-1- and endomorphin-2-induced dopamine efflux in the nucleus accumbens of freely moving rats. Muscimol (2500 pmol) and bicuculline (5 and 10 nmol) increased basal dopamine efflux. Bicuculline (50 pmol) inhibited the muscimol (2500 pmol)-induced dopamine efflux. Muscimol (250 pmol), but not bicuculline (50 and 500 pmol), enhanced the endomorphin-1 (25 nmol)-induced dopamine efflux. Bicuculline (50 pmol) counteracted the muscimol (250 pmol)-induced increase of the endomorphin-1-elicited dopamine efflux. Neither muscimol (25 and 250 pmol) nor bicuculline (50 and 500 pmol) affected the endomorphin-2 (25 nmol)-induced dopamine efflux. The doses mentioned are the total amount of drug over the infusion period (25 or 50 min) that varied across the drugs. The finding that muscimol and bicuculline increased basal dopamine efflux may imply that these drugs acted at different sites. It is suggested that (1) muscimol acts at GABA(A) receptors on GABA-ergic neurons that exert an inhibitory control of dopaminergic neurons and, accordingly, disinhibits these dopaminergic neurons, and that (2) bicuculline acts directly at GABA(A) receptors on dopaminergic neurons and, accordingly, removes the inhibitory control of these dopaminergic neurons. The finding that an agonist, but not antagonist, of GABA(A) receptors enhanced the endomorphin-1's effects might indicate that endomorphin-1 produced a floor effect at the level of GABA(A) receptors located on presynaptic, dopaminergic terminals. Finally, the present results support our earlier reported notion that endomorphin-1 and endomorphin-2 increase accumbal dopamine efflux by different mechanisms
Analisi della correlazione tra dimensione facciale verticale e muscolo massetere in pazienti in crescita
OBJECTIVES. The aim of the present study was to analyse the anatomical three-dimensional characteristics of mas- seter muscle in growing subjects by using an ultrasound method.
MATERIALS AND METHODS. The sample comprised 60 prepubescent sub- jects. According to the facial divergence (Frankfort-Mandibular plane Angle, FMA) the subjects were divided into three groups with different underlying verti- cal facial patterns: brachyfacial, FMA < 22°; mesofacial, 22°<28°; dolichofacial, FMA >28°. For each subjects, an ultrasound scan was carried out in order to analyse the masseter muscle’s width, thickness, cross-sectional area and volume. RESULTS. Measurements of the whole masseter in dolichofacial patients were significantly smaller when compared with brachyfacial and mesofacial individuals.
CONCLUSIONS. A significant negative cor- relation was found between the ultrasound measurements and the divergence (FMA
Quantitative analysis of the maxilla and the mandible in hyper- and hypodivergent skeletal class II pattern
10.1111/j.1601-6343.2008.01431.xOrthodontics and Craniofacial Research1219-1