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Get PDFMost chromosomes of cleaving mouse embryos formed spherical structures called as prenucleolar bodies. Embryos stained with fluorescing dyes selective for AT-rich regions of DNA indicated that chromosome centromeres were organized by prenucleolar bodies and that chromosomes at pre-prophase of the cleavage division started to condense with their centromere regions aligned towards the peripheries of spheres. Embryo chromosomes as well as prenucleolar bodies were shown to bind a monoclonal antibody to spliceosomal snRNAs, which are contrasted to the nucleoli or chromosomes of somatic cells. More than 10 prenucleolar bodies were found in the pronuclei at the earliest stage after fertilization and40 of them at most, diploid number of chromosomes of the mouse, in the nuclei of the 2-cell embryos. The number was decreased later in the cell cycles and at the 4-cell stage. Hence, every chromosome of cleaving mouse embryos is highly active in constructing prenucleolar bodies and behaves during the interphase until mitosis as a unit of the body; either as a single unit or as a member of the units fused. In other words, the prenucleolar bodies function as centers orienting chromosome-chromosome configuration in the fertilized eggs.departmental bulletin pape
Get PDFThe purpose of this article is to review the literature on the relationship between occlusal discrepancies and temporomandibular disorders (TMD) and to summarize the guidelines of treating TMD by prosthetic rehabilitation.To date, the relationship between occlusal condition and TMD has not been confirmed, although there is a current trend toward making a weak correlation between occlusal interference and TMD. Furthermore, several types of occlusal discrepancies have been considered as variable features of the norm. But unstable occlusion in the intercuspal position may cause TMD.In cases of restored dentition, the problem is probably different and iatrogenic TMD are not rare. Namely, malformed occlusal surfaces, defects in anterior guidance, occlusal curvature, and vertical dimension may lead to some TMD trouble.According to these recent concepts the treatment modalities of TMD have been changed. Conservative treatments such as counseling, behavioral modification, physical therapy, pharmacotherapy,and interocclusal appliances should be the first choice, and treatments that lead to drastic changes of occlusion are not recommended.departmental bulletin pape
Get PDFThe objective of this study was to elucidate changes in the health-related lifestyle of Mongolian pastoralists in China in connection with their urbanization. A total of 592 people participated in a survey that included a medical examination and an interview questionnaire. Files of 72 pastoral Mongolians, 78 urban Mongolians, 380 urban Han/Man and 21 urban Hui were used for this analysis. Urban Mongolians consumed meat and milk products less frequently than did pastoral populations (p<0.001), and consumed fish and vegetables more frequently than did pastoral populations (p<0.001). Urban Mongolian consumed mutton, beef, rengyo fish, milk, milk tea, curd, butter, yogurt, and sheep milk less frequently (p<0.05) and pork, sword fish, and dried milk more frequently (p<0.05) than pastoral Mongolian. Male pastoral Mongolians were more likely to drink and smoke than were urban Mongolians (p<0.01), urban Han/Man (p<0.01), or urban Hui (p<0.01). The lifestyles of pastoral Mongolians in Inner Mongolia, China have changed in connection with urbanization. Understanding of the traditional pastoral lifestyle and the urban-living acculturation process will contribute to maximizing the positive impacts of urbanization on people’s health in Inner Mongolia.departmental bulletin pape
Get PDFIntestines of mice with colitis caused by dextran sulfate sodium (DSS) contain more Bacteroidaceae cells than untreated controls. We investigated the roles of intestinal bacteria and succinic acid, a by-product of Bacteroidaceae metabolism, in this model of colitis.CBA/J mice were given 3% DSS in water for 14 days. After mice were anesthetized and killed, concentrations of organic acids in stools from the cecum and colon were measured. The resected rectum and colon were washed with sterile saline; some specimens were incubated with imipenem in saline for 1 h to kill bacteria on the surfaces andothers were not. Their homogenates were cultured anaerobically and aerobically. Separately, 1 mL of 20 mM succinic acid was infused into the rectum of mice, whose anal verge was glued. Animals were anesthetized and killed the next day. The rectum and colon were examined histologically.Concentrations of succinate were higher everywhere in the colon of mice with colitis than in controls. Mice with colitis had more Bacteroidaceae cells, especially B. caccae, than controls. Mice given succinate enemas had focal erosions of the mucosa and edema of the submucosa.Succinic acid, produced abundantly by members of the family Bacteroidaceae, especially B. caccae, may be the ulcerogenic agent in DSS colitis.departmental bulletin pape
Get PDFThe orofacial region performs the essential functions of mastication and speech, as well as that of appearance, which for better or worse evokes an instant and instinctive response in other people. In this region, tissue loss caused by surgical resection of a malignant tumor has atremendous negative impact on the patient'squality of life, with deep mental and psychological repercussions. Therefore, from the standpoint of preserving form and function, radiotherapy has a major role to play in the treatment of malignant tumors in the orofacial region. That said, important organs, such as sensory organs, are present in close proximity to each other in this small region. During the irradiation process, therefore, it is important to ensure that the lesion is sufficiently irradiated while simultaneously protecting the surrounding normal tissue. In certain cases of radiotherapy of malignant tumors of the orofacial region, the use of radiotherapy prostheses can help to satisfy a basic principle of radiotherapy: that of delivering a lethal dose to the tumor while mini mizing irradiation to normal tissue. In recent years, medical and dental experts have taken a team approach to creating and employing a variety of radiotherapy prostheses, working towards improving the treatment record for malignanttumors as well as reducing complications in sur rounding normal tissue. As a result, patients treated with radiotherapy prostheses are now able to receive post-radiotherapy prosthodontic treat ment in a dramatically safer and more rapid man ner. It is clear that radiotherapy prostheses con tribute significantly to the improvement of these patients' quality of life.departmental bulletin pape
Get PDFSchool-based dental health activities conducted in Hiraizumi over the past 20 years have remarkably improved the dental health status of schoolchildren. For example, DMFT index of 12-year-old children decreased to 1.5 in 1998,one-half that of the national average. School dental health activities, which were focused on dental health education, resulted in an increase of filled teeth rates, a decrease in the number of missing teeth, and a decline in incisor caries (1979-1986). In addition, the introduction of a school-based fluoride mouth-rinsing program (1986-） showed a positive effect on the prevention of dental caries; a significant decrease was observed in the overall prevalence of dental caries, particularly in the molars.In Japan it seems advantageous to promote the dental health of schoolchildren by school-based programs that combine dental health examination, dental health education and fluoride mouth-rinsing program. Especially, to prevent dental caries in the mandibular first molars more effectively, it is recommended to start fluoride mouth-rinsing at age 5.departmental bulletin pape
Get PDFThe pathophysiology of sensorineural hearing impairment, which is a common clinical disorder, remains yet to be determined. For prelingual hearing loss, epidemiological data show that 1 neonate in 1,000 is born with severe to profound hearing loss, and in half of that number the loss is inherited. Some genes responsible for sensorineural hearing impairment have been cloned during the last several years, and the underlying mechanisms causing hearing impairment have begun to be clarified with the advent of recent developments in molecular genetics. Cases of non-syndromic deafness are classified by the mode of inheritance (DFNA, dominant; DFNB, recessive; DFN, X-linked), with the loci being numbered in the order of discovery. To date, 31autosomal dominant, 28 autosomal recessive, and 6 X-linked non-syndromic sensorineural hearing impairment loci have been mapped, and 17 genes have been cloned (Hereditary Hearing Loss Homepage, http://danallab-www.uia.ac.be.dnalab/hhh/). We have identified mutations in four of those 17 deafness genes in Japanese families. Clinical and genetic findings of the above disorders are reviewed.departmental bulletin pape
Get PDFRespiratory symptoms and hypersensitivity pneumonitis (HP) among mushroom workers have been well documented. Inhalation of shimeji mushroom (Tricholoma conglobatum) spore has been assumed to be the cause of HP amongindoor shimeji cultivating workers. We isolated and partially characterized the allergenic componentsof shimeji. The sera from 9 HP patients, 10 asymptomatic shimeji workers and 15 normal individuals were examined for shimeji specificlgG and lgA antibodies by ELISA using crude shimeji extract. Shimeji specific lgG- and lgA-antibodies were higher in sera from HP patients than in sera from control subjects. Crude shimeji spore extract was separated and purified by HPLC followed by SDS-PAGE, and their antigenic activity was studied by immunoblotting with a pool of sera from patients. Sera from all HP patients showed lgG and lgA antibody activities to 21, 16 and 14 kD proteins extracted from shimeji spore. The 21 kD protein contained internal peptide amino acid sequence of Gly-Gly-Thr-Val-lle-Asn-Leu-Leu-Gly, Gln-Arg-Phe-Glu-Glu and Gln-Gly-lle-Tyr. These results demonstrate that shimeji spore extract contains multiple proteinous components, which have antigenic activity to react withthe sera from HP patients among shimeji workers.These proteins may be the potent sensitizing allergens to cause HP among shimeji cultivating workers.departmental bulletin pape
Get PDFThe purpose of this study was to analyze the vibration of obturator framework designs and investigate the vibration effects of connecting parts of the components. Four designs of maxillary obturator framework were used in this study: a partial palatal plate with continuous bar (A), with a part of continuous bar (B), without continuous bar (C)and without continuous bar and indirect retainer (D). In order to investigate the vibration of each framework (total) and some component parts, the measurement points of the retentive parts were devided into 3 groups; anterior, middle and posterior. The framework was activated by a vibration generator. The vibration of each measurement point was detected with a laser doppler vibrometer. The frequency response signals were conducted by an FFT Analyzer between 220-2000 Hz. The maximum displacement (MDP) and the decay rate (DR) of the vibration were analyzed statistically by ANOVA and Fisher's PLSD (p<0.05). The result showed that in the posterior group, MDP of D was higher than those of A, B and C. Regarding the anterior, middle and total group, the DR of D were lower than A, B and C. It was suggested that D might be clinically unfavorable.departmental bulletin pape
Get PDFA visible light curing sealant was developed for the prevention of caries on the smooth surfaces especially on the proximal surfaces. The sealant is mainly composed of dimethacrylate monomers. It contains a total amount of 2.28 mass% fluoride as poly(methyl methacrylate-co-methacryloyl fluoride) and sodium fluoride. The fluoride-containing sealant could be successfully applied to the proximal surfaces between the first and second primary molars by making access to the interproximal space with an orthodontic separating module. Availability of fluoride was assessed by the concentration of fluoride released into 1 ml of distilled water as a function of time from disks 5 mm in diameter and 0.2 mm in thickness.Ten µg of fluoride was measured on the first day; after 3 days the rate remained fairly constant at about 1 µg/day fora period of 28 days. The fluoride uptake and theimproved acid solubility were investigated in vitro using bovine incisors. The fluoride of the control, that is enamel without sealant treatment, was not detectable. The fluoride incorporated into enamel after 37 hours application was 2100 ppm at 2 µm from the enamel surface. The enamel solubility to acids decreased by the fluoride incorporation.departmental bulletin pape