求心性の歯周組織感覚入力により誘発された前頭前野の活動は咬合力を抑制する

The prefrontal cortex (PFC) plays an important role in several cognitive functions, such as planning, decision making, and social behavior. We previously reported that periodontal sensory input significantly increases PFC activity during the motor task of maintaining occlusal (biting) force. However, the relationships between periodontal sensation, PFC activity, and the performance of motor tasks, have not been evaluated in detail. Therefore, using functional near-infrared spectroscopy, we investigated PFC activity by monitoring changes in cerebral blood flow (CBF) to specific areas of the PFC that corresponded to changes in occlusal force generated during 4 different biting tasks: 1) occlusion with the central incisor with an interocclusal distance of 5 mm (BI-5 mm); or 2) 10 mm (BI-10 mm); 3) occlusion with the first molars with an interocclusal distance of 5 mm (BM-5 mm), or 4) 10 mm (BM-10 mm). Occlusion of molars generated increased PFC regional CBF as the interocclusal distance decreased (BM-10 mm vs BM-5 mm). No significant differences in CBF during occlusion of incisors were found when comparing 5 mm and 10 mm intercostal distances (BI-5 mm vs BI-10 mm). The mean occlusal force generated by BM-5 mm occlusion was significantly lower than that generated by BM-10 mm occlusion. Taken together, our results suggest that the PFC decreases efferent signaling to motor units, to reduce occlusal force generated when periodontal sensation, which is greater when the interocclusal distance is reduced, is primarily responsible for maintaining occlusal force in the absence of sensations from the temporomandibular joint and muscle spindles

MOTION OF CENTRE OF PRESSURE DURING STANDING ON TIP TOE ON ONE LEG: ASSOCIATION WITH FOREFOOT SHAPE OF CLASSIC BALLET DANCERS

This study clarified how the centre of pressure (COP) is kept in the forefoot area during standing on tip toe on one leg by classical ballet dancers. During standing on tip toe on one leg with ballet shoes, the weight is distributed around the first and second toes and at the distal point of the second metatarsal bone ideally. Thus, the supporting surface during standing on tip toe on one leg would be affected by alignment of the metatarsal bones. Motions of the COP during standing on tip toe on one leg were investigated for ten female recreational dancers and six female professional dancers in classical ballet. The results suggested that balance holding time tended to be longer as the distal points of the metatarsal bones aligned more like a straight line in recreational dancers

A report of three cases of diabetic nephropathy satisfactorily treated with traditional herbal medicine

We reported that three cases of diabetic nephropathy, who had overt proteinuria, were treated satisfactorily not only for their symptoms but also renal nephropathy with traditional herbal medicine over the long term. In Case 1, the level of S-Cr had changed from 1.2 to 2.0 mg/dl over 98 months, in Case 2 from 0.9 to 1.9 mg/dl over 70 months, and in Case 3 from 1.1 to 2.9 mg/dl over 81 months, acceptably moderate increases, meaning that the progression of their renal insufficiency was controlled over the long term. At the same time, the symptoms of hotness, numbness and edema were improved. Diabetic nephropathy with overt proteinuria is known to develop into renal failure after several years. In these cases, traditional herbal medicine was considered responsible for improving their QOL and prolonging the pre-dialysis period of diabetic nephropathy. 顕性蛋白尿期にある糖尿病性腎症の患者に漢方治療を施行した。その結果,随伴する諸症状の改善のみならず長期問,腎機能低下の進行を抑制した3症例を経験したので報告した。症例lでは,98ケ月の観察でS-Cr値はl.2から2.0mg/dl,症例2では70ケ月の観察で,S-Cr値は0.9から1.9mg/dl,症例3では81ケ月の観察で,S-Cr値は1.1から2.9mg/dl,と長期間腎機能低下の進行を抑制した。同時に,手足の火照りやしぴれ感,下肢の浮腫などの症状の軽快も認めた。持続的に蛋白尿を認める顕牲腎症期に至った糖尿病性腎症は数年の経過で,末期腎不全から血液透析に至ると言われている。今回の症例から和漢薬は,糖尿病性腎症における腎機能障害に対して腎機能障害の進行抑制作用を有する可能性が示唆された。このことから,和漢薬は糖尿病に随伴する諸症状を緩和し,QOLを改善するのみでなく,血液透析導人までの期間を延長し,予後を改善したと考えられた

Does Periodontal Tactile Input Uniquely Increase Cerebral Blood Flow in the Prefrontal Cortex?

We previously studied the effect of peripheral sensory information from sensory periodontal ligament receptors on prefrontal cortex (PFC) activity. In the dental field, an alternative dental implant without periodontal sensation can be applied for missing teeth. In this study, we examine whether periodontal tactile input could increase cerebral blood flow (CBF) in the PFC against elderly patients with dental implants lacking periodontal tactile (implant group), elderly individuals with natural teeth (elderly group), and young individuals with natural teeth (young group). The experimental task of maintaining occlusal force as closed-loop stimulation was performed. Compared with the young group, the elderly group showed significantly lower CBF. Contrastingly, compared with the young group, the implant group showed significantly lower CBF. There were no significant differences between the elderly and implant groups. Regarding the mean occlusal force value, compared with the young group and the elderly group, the implant group had a numerically, but not significantly, larger occlusal force exceeding the directed range. In conclusion, the periodontal tactile input does not uniquely increase PFC activity. However, increased CBF in the PFC due to the periodontal tactile input in the posterior region requires existing attention behavior function in the PFC

Application of artificial intelligence in the dental field : A literature review

Purpose: The purpose of this study was to comprehensively review the literature regarding the application of artificial intelligence (AI) in the dental field, focusing on the evaluation criteria and architecture types. Study selection: Electronic databases (PubMed, Cochrane Library, Scopus) were searched. Full-text articles describing the clinical application of AI for the detection, diagnosis, and treatment of lesions and the AI method/architecture were included. Results: The primary search presented 422 studies from 1996 to 2019, and 58 studies were finally selected. Regarding the year of publication, the oldest study, which was reported in 1996, focused on “oral and maxillofacial surgery.” Machine-learning architectures were employed in the selected studies, while approximately half of them (29/58) employed neural networks. Regarding the evaluation criteria, eight studies compared the results obtained by AI with the diagnoses formulated by dentists, while several studies compared two or more architectures in terms of performance. The following parameters were employed for evaluating the AI performance: accuracy, sensitivity, specificity, mean absolute error, root mean squared error, and area under the receiver operating characteristic curve. Conclusion: Application of AI in the dental field has progressed; however, the criteria for evaluating the efficacy of AI have not been clarified. It is necessary to obtain better quality data for machine learning to achieve the effective diagnosis of lesions and suitable treatment planning

Effect of Keishi-bukuryo-gan on asymptomatic cerebral infarction for short term

無症候性脳梗塞患者に対する桂枝茯苓丸の効果を検討した。142例(男性32例,女性110例,平均年齢68.9才)を対象とし,副作用のため内服を中止した3例を除く139例に対して,桂枝茯苓丸エキス1日量7.5gを12週間投与した。投与開始時と比較して,改訂長谷川式簡易知能評価スケール,Apathyスケール(やる気スケール),SDS(うつ状態スケール)は有意に改善した。また,頭重感,頭痛,めまいの自覚症状も桂枝茯苓丸の投与により改善し,拡張期血圧は投与前に比べ有意に低下した。これらの結果から,桂枝茯苓丸が無症候性脳梗塞に伴う認知機能の低下,精神症状や自覚症状の悪化に対して有効である可能性が示唆された。 The efficacy of Keishi-bukuryo-gan in patients suffering from asymptomatic cerebral infarction was studied. 142 patients, 32 males and 110 females, with a mean age of 68.9 years, were enrolled and analyzed, and 139 completed the study. They were given Keishi-bukuryo-gan extract (7.5g/day) three times a day for 12 weeks. In comparison to the beginning of the study, Keishi-bukuryo-gan showed improvement with statistical significance in the mean revised version of Hasegawa\u27s dementia scale, Apathy scale and Self-rating depression scale. The number of patients with subjective symptoms as headdullness, headache and dizziness decreased by the treatment with Keishi-bukuryo-gan, and diastolic blood pressure was decreased with statistical significance as compared to the beginning of the study. These results suggest that Keishi-bukuryo-gan is effective against dysfunction of acknowledgment, emotional disorder and subjective symptoms with asymptomatic cerebral infarction

Optical pumping NMR in the compensated semiconductor InP:Fe

The optical pumping NMR effect in the compensated semiconductor InP:Fe has been investigated in terms of the dependences of photon energy (E_p), helicity (sigma+-), and exposure time (tau_L) of infrared lights. The {31}P and {115}In signal enhancements show large sigma+- asymmetries and anomalous oscillations as a function of E_p. We find that (i) the oscillation period as a function of E_p is similar for {31}P and {115}In and almost field independent in spite of significant reduction of the enhancement in higher fields. (ii) A characteristic time for buildup of the {31}P polarization under the light exposure shows strong E_p-dependence, but is almost independent of sigma+-. (iii) The buildup times for {31}P and {115}In are of the same order (10^3 s), although the spin-lattice relaxation times (T_1) are different by more than three orders of magnitude between them. The results are discussed in terms of (1) discrete energy spectra due to donor-acceptor pairs (DAPs) in compensated semiconductors, and (2) interplay between {31}P and dipolar ordered indium nuclei, which are optically induced.Comment: 8 pages, 6 figures, submitted to Physical Review