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Get PDFThe parasympathetic nerves regulate colonic motility and defecation. The vagal nerve controls the right colon and the pelvic nerve permeates the left colon and rectum via the rectal branches of the pelvic plexus (RBPP). This investigation aimed to measure the functional changes of the colon and rectum after RBPP-transection for over six months. RBPP-transection was performed in 15 dogs. Five dogs each were sacrificed immediately, one month, and six months after RBPP-transection. The stool condition, colorectal transit, defecation reflex, colorectal response to electrical stimulation, and pathological degeneration was investigated prior to, one month after, and six months after RBPP-transection. Four of the 5 dogs observed had loose stool one month after RBPP-transection, and one of the 3 had recovered six months later. Half transit time (HTT) at transverse colon got longer in six of the 8 in one month. Six months later, HTT got shorter in three of the 4 than that of one month. Defecation reflex was not observed one month after RBPP-transection, but noted in two of the 5 six months later. These results may suggest that vagal nerve compensates for the oral site of the left colon after denervation of the pelvic nerve which is originally distributed.departmental bulletin pape
Get PDFTo explain the pain and dysfunction of neck during jaw movement associated with malocclusion, the physiologic relationships between jaw and cervical movement should be understood. However the complicated reflex effects made it difficult to investigate the biomechanical relationship between the head-neck components. For this reason we have created a model for mechanical system dynamic analysis of the normal stomatognathic system to assess the biomechanics of the cervical movement and muscle activity during jaw movement. We have also statistically validated the model and quantitatively verified the model to the human subject by the amounts and conditions of cervical muscle activity. During jaw openingclosing phases the movement of the model was highly correlated to the subject with an identical movement. However low consistency was achieved during intercuspid phase. These findings indicate the establishment of a valid system, which can be used to evaluate the biomechanical relationships between jaw and cervical movement. Moreover the model verification of cervical muscle activity indicate the mechanical action of jaw can be the primary factor to modify cervical muscles, and cervical muscles coordinate to resist changes in head balance during jaw movement to maintains head posture.departmental bulletin pape
Get PDFThirteen Japanese patients with hyper-IgM syndrome but normal CD40 ligand were characterized. All patients had mutations in AID (activationinduced cytidine deaminase) gene. Five of them had a missense mutation of Arg112His. In all patients, serum IgG, IgA and IgE levels were undetectable, B cells failed to produce detectable amounts of IgE even if cultured them with anti-CD40 and IL-4. Somatic hypermutation (SHM) was also impaired in their peripheral blood B cells. These results suggest that Arg112 is the hot spot of AID mutation and demonstrate that AID plays indispensable roles in class switch recombination (CSR) and somatic hypermutation (SHM) in human B cells. In addition, serum IgM levels in the patients have been continuously high even after proper intravenous immunogloburin infusion (IVIG) and without infection, indicate that AID has the function to induce spontaneous IgM production in B cells.departmental bulletin pape
Get PDFThe purpose of this study was to examine how the periodontal sensory inputs of working-side maxillary posterior teeth affect nonworking-side anterior temporalis activities at the starting jaw position of the slow-closing phase in mastication. Six subjects with normal occlusion were asked to bite an incisal block to maintain the initial jaw position of the slow-closing phase and to generate jawclosing muscle activities. Bipolar needle electrodes were inserted into the nonworking-side anterior temporalis to record spike discharges from a single motor unit. To stimulate the periodontal mechanoreceptors, mechanical stimulations were applied to the working-side maxillary first molar, first and second premolar in buccopalatal, palato-buccal, and apical directions. Meanwhile, we examined changes in the discharge frequency of the motor unit activities of the nonworking-side anterior temporalis. We found that the palato-buccal stimulation to the working-side maxillary first molar and the apical stimulation to each working-side maxillary posterior tooth significantly increased the nonworking-side anterior temporalis activities; however, palato-buccal and bucco-palatal stimulations applied to the first and second premolar didn't. Thus, differential responses of the nonworking-side anterior temporalis are found by the working-side maxillary first molar and premolar stimulations. These findings may be due to some differences in function between molar and premolar.departmental bulletin pape
Get PDFSpinal cord evoked potentials (SCEPs) measurement is widely used for level diagnosis of spondylotic myelopathy. However, because of the restriction of spatial resolution, SCEPs do not distinguish the neurophysiological activities among tracts in the spinal cord without invasive methods. Magnetic field measurement has the theoretical advantage of high spatial resolution, compared with electric measurement. We recorded spinal cord evoked magnetic fields (SCEFs) in the thoracic spinal cord after stimulation to the motor area in felines, and estimated the source of the magnetic fields. SCEFs showed a quadrupolar pattern, and conducted in a cranial-to-caudal direction at 55 m/sec. According to this result, we estimated that the SCEFs after stimulation to the motor area were generated by the contralateral corticospinal tract. Furthermore, the estimated dipole of the SCEFs after stimulation to the motor area was located on the contralateral side in the spinal cord. These results correspond with the anatomical location of the corticospinal tract of felines, and suggest that magnetic field recording can detect the magnetic source localization of each tract in the spinal cord.departmental bulletin pape
Get PDFNeuronal loss is frequently found in brains of patients with human immunodeficiency virus (HIV)-encephalopathy. Extensive apoptosis of neurons is probably involved in the development of HIV-encephalopathy. The present study was designed to investigate the mechanism of neuronal apoptosis. For this purpose, we examined autopsy brains of two patients with HIV-encephalopathy. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells and active forms of caspase-3- and -8-positive cells, including neurons, were found in the perivascular regions of the brains. In these regions, TNF-related apoptosis-inducing ligand (TRAIL)+ macrophages were also observed. We also examined brains of HIV-1-infected mouse model inoculated with human cells. In these brains, TUNEL+ neurons were also found in the perivascular region, the site where infiltrated HIV-1- infected and TRAIL-expressing macrophages were observed. Using an in vitro-culture system, we also demonstrated that the HIV-1-infected monocyte-derived macrophages preferentially expressed TRAIL and that the addition of HIV-1- infected macrophages or human TRAIL-overexpressing mouse cells to cultured mouse primary neurons/glia resulted in neuronal apoptosis. Our results suggest the involvement of TRAIL expressed on HIV-1-infected macrophages in the induction of neuronal apoptosis in infected brain.departmental bulletin pape
Get PDFThis study examines the effects of denture adhesive on the retention and stability of complete dentures and the masticatory function. The authors estimated the stability of complete dentures from 3-dimensional (3-D) denture movement and rotational denture movement and additionally the masticatory function from cycle time and chewing time. Six edentulous subjects who participated in this study had old and newly fabricated complete dentures. Upper denture movement was recorded using a 3-D motion capture system while chewing 3 kinds of food (peanuts, fish paste, raisins). Both the new and old dentures showed that using a denture adhesive contributes to reducing 3-D denture movement, rotational denture movement and chewing time during chewing the various foods. The cycle time in new and old dentures was statistically unaffected by applying denture adhesive. There was no statistically significant difference in improvement in 3-D denture movement or rotational denture movement between the new and old dentures, for any of the foods. This study observes the overall effect of denture adhesive during use for both dentures. The results of this study suggest that denture adhesive contributes to reducing denture movement and so improves chewing function.departmental bulletin pape
Get PDFThe purpose of this study is to evaluate the masticatory muscle activity and mandibular movement during function in marginal mandibulectomy patients. Three marginal mandibulectomy patients and three healthy subjects participated in this study. The activities of the temporalis (TA) and masseter muscles (MM) on the normal and resected sides during maximum voluntary clenching (MVC) and gum chewing (Gch), and mandibular movement during Gch were analyzed. Paired t-test, Student's t-test and one-way ANOVA were performed at P < 0.05. For MVC, integrated EMG (iEMG) in patients was lower than in healthy subjects. When iEMG of each muscle activity in patients was compared, TA activity on the resected side was greater than that of MM. There were no differences between the normal and resected sides in TA or MM. For Gch, no differences in iEMG, burst or chewing time were found between patients and healthy subjects. MVC was greater than Gch in healthy subjects, but no difference was found in patients. The range of mandibular movement along the X axis in patients was greater than in healthy subjects. Within the limitations of this study, EMG activity in patients during MVC was remarkably lower than that in healthy subjects, and altered mandibular movement was observed.departmental bulletin pape
Get PDFThe purpose of this study was to investigate whether lidocaine could be transported through excised rat skin in vitro using alternating current (AC). In addition, the relationships between factors such as voltage and frequency, and transported lidocaine concentration were studied using the in vitro model. A pair of platinum plate electrodes was installed at opposite ends of two cylindrical glass cells in parallel to the full-thickness rat skin. The donor compartment was filled with 10 % lidocaine hydrochloride, and the receptor compartment with Ringer solution. A sinusoidal wave was applied between the electrodes at 5 kinds of constant voltages at 1 kHz and at 4 kinds of frequencies at 20 volts. Our experimental system was successfully used to quantify the concentration of transported lidocaine induced by AC application. The applied sinusoidal waves evoked the transport of lidocaine through the rat skin at every voltage and frequency protocol. Our results suggest that the applied electric voltage and frequency affect the movement of the lidocaine ions. We conclude that the transdermal delivery of lidocaine by AC iontophoresis has a possibility to use for local anesthesia and the pain management of the skin.departmental bulletin pape
Get PDFIt has been suggested that oral care is essential for improving the quality of life (QOL). The aim of oral care involves not only maintenance of oral health but also enhancement of mastication and appetite by means of improving taste sensitivity. There are, however, few studies that have investigated the effect of oral care on taste sensitivity. In the present study, we focused on tongue brushing among oral care and examined the changes in taste sensitivities by mild tongue brushing in the nursed elderly. Ninety subjects, over 64 years old with ability to communicate, were divided into 2 groups, one was the cared group (subject's tongue was brushed) and the other was the control group (not brushed but rinsed). The thresholds for four primary tastes such as saltiness, sourness, sweetness and bitterness were measured before and after treatments using the whole mouth method. The mean recognition thresholds for salty and sour tastes significantly decreased after tongue brushing in the cared group, while those for all four tastes were not changed after mouth rinsing in the control group. The present result suggests that mild tongue brushing may enhance taste sensitivity of saltiness and sourness in the nursed elderly.departmental bulletin pape