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Biomedical subjects

S Yamaguchi

Publications and source records attributed to S Yamaguchi.

At least 901 records · Page 50Linked to original sources
PubMed1989

[Group therapy for periodontal disease. 1. Practical application of CPITN and the effects of group therapy].

The purpose of this study was to determine the oral conditions in bakery workers (473 subjects) in addition to the screening system of O'Leary and CPITN, designed for rapid recording of the level of periodontal treatment needs, and to evaluate the periodontal treatments, managed by professional cleaning (scaling) and oral hygiene instruction. The assessment of the prevalence and severity of periodontal disease and resultant treatment needs in this group showed the characteristics of chronic periodontal disease in an advanced stage in persons aged 25-29 and 50-54. 228 patients were selected for treatment for nine months and examined accurately for their periodontal condition. 137 patients continued the following group therapy three times and were reevaluated. Following the group therapy, the oral hygiene status and subjective symptoms of bleeding were improved in all groups, the effectiveness of the treatment on sextants, scoring cord three, four, showed markedly high. To achieve the treatment with few individual appointments, it is necessary to increase our knowledge of how these groups live, depending on the diversity of life style and the differences in ethnic consciousness.

Adult↗
PubMed1989

[Morphological study of periodontal tissues in the initial stage of periodontal disease. Part 1. Application of a morphological measurement and a system for evaluating the periodontal status].

The functional aberration of occlusion, based on the morphology of the alveolar process, causes chronic irritation of the periodontium in addition to the concomitant effect of other local environment factors. This investigation was designed to study the role of morphological characteristics in the periodontal disease process. The periodontal health of 22 subjects was recorded by clinical and roentgenological measurements of the loss of periodontal tissue. The criteria for this selection were no loss of or a crowding of adjoining teeth and no disharmony in occlusal contact. Morphological data were measured around the premolars and molars of lower jaws on the study models individuals, in bucco-lingual width of the alveolar bone in relationship to the width of the crown and the sagittal figure of the Spee curve etc. by using a three-dimensional analyzer. The subjects were categorized as Type II when the records indicated a ratio of the crown width/bone width of 1/1.2. Types I and III, depended on a greater and smaller ratio, respectively. Type W symbolized the alveolar process, of which the interproximal bone showed a considerable curvature mediodistally. Type F showed a flat pattern. The sagittal figure of the Spee curve was divided into four patterns: Pattern A or B, when the cusp of the canine and first premolar leveled over or on the occlusal plane; Pattern C, when the cusp of the canine leveled over and the first premolar under the occlusal plane, and Pattern D, when all cusps, canine, premolar and molar, were under the occlusal plane. The distance from the occlusal plane to the deepest point of the Spee curve was divided into four groups: Pattern a, when the distance was 0-1.0 mm, Pattern b, 1.1-2.0 mm, Pattern c, 2.1-3.0 mm and Pattern d, 3.1-4.0 mm. These results suggest that the morphological evaluation is a useful diagnostic indicators on a rational basis. The morphological characteristics might be related to the presence of periodontal disease and allowed to speculate the pathological changes in established stage, and also to the response to periodontal treatment in the initial stage of periodontal disease.

Alveolar Process↗
PubMed1989

[Morphological study of periodontal tissues in the initial stage of periodontal disease. Part 2. Analysis of morphological measurement and status of periodontal disease].

The morphological characteristics of periodontal tissue in periodontal disease have been interpreted differently by a number of clinical observers. Many have reported that the malposition and functional malocclusion of teeth is injurious to the periodontium. We reported in Part I that a system for evaluating periodontal status was developed for the diagnosis and management of the interproximal area at the initial stage of bone resorption. The patient group consisted of 36 adults, from 21 to 55 years of age. The severity score represented the calculated loss of periodontal support tissues: loss of alveolar bone, evaluated roentgenologically, bone level and pattern in vertical and horizontal form, periodontal pocket and gingival inflammation. Because poor oral hygiene and other factors caused swelling by gingival inflammation, we obtained study specimens from patients with chronic periodontal disease after a few tooth brushing instructions, and scalings during initial therapy in order to detect initial and established pathological changes in periodontal tissue. The purpose of this study was to clarify the relationship between periodontal disease status and morphological diagnostic indicators and different degrees of harmony and disharmony in the lower jaw. In all age groups the average percentage of bone loss and intraosseous defects tended to be higher in the groups categorized as Type III and Type F, and in the area that showed a very deep concave Spee curve to the occlusal plane in Pattern D. We considered that these morphological characteristics might be of secondary importance for diagnosis. Oral local factors were the primary extrinsic factor in the pathogenesis of horizontal and vertical interproximal bone absorption in the area of the premolars and molars.

Alveolar Process↗
PubMed1989

[Age-related cerebral white matter changes on computed tomography].

Changes of cerebral white matter on computed cranial tomography related to aging were studied in 70 subjects aged 30 to 94 years. The subjects had no histories of cerebrovascular accidents and no abnormalities in the central nervous system were shown by physical examinations nd CT scans. We measured the average attenuation values (CT numbers) of each elliptical region (165 pixels, 0.39 cm2) in the bilateral thalamus and twelve areas of deep white matter. Multiple regression analysis was used to assess the effects of age, cranial size and cranial bone CT numbers on the brain CT numbers. We also studied the association between brain CT numbers and brain atrophy, hypertension, diabetes mellitus. CT numbers of frontal white matter surrounding anterior horns decreased with aging in 70 subjects aged 30 to 94 years. No significant correlation between age and brain CT numbers was found in any other region by multivariate analysis, because of the prominent effect of cranial bone CT numbers on brain CT numbers. Although no age-related changes of white matter CT numbers was found in 41 subjects aged 30 to 65 years, there were significant negative correlations between age and white matter CT numbers at all regions in 29 subjects aged 66 to 94 years. Brain atrophy was associated with brain CT numbers. No association was found for hypertension or diabetes mellitus. Brain CT numbers decreased with aging even in neurologically healthy persons in older age. Brain CT numbers also decreased as cerebral atrophy advanced.

Adult↗
PubMed1989

Experimental study on filtrability of polymorphonuclear leukocyte suspensions.

Filtrability of a suspension of polymorphonuclear leukocytes (PMNs) was examined in a Nuclepore membrane filtration system utilizing a gradually reduced pressure difference with or without an additional negative pressure. The filtration process was continuously recorded using a TV-video system for data analysis. The PMN content in the filtrate was directly measured. The pressure-flow relation was analyzed in terms of the relative resistance of the PMN suspension to that of the suspending medium. The relative resistance of the PMN suspension increased with an increase in the filtered volume until it approached infinity at the level of low pressure difference (2.8 - 0 cmH2O). The remarkable increase in flow resistance was closely associated with the plugging of PMNs in the membrane pores. At high pressure differences (12.8 - 10 cmH2O, 7.8 - 5 cmH2O), the relative resistance increased up to finite values, as the filtered volume increased. The variation in the relative resistance was greatly dependent upon the pressure difference or the flow condition. The amount of filtered cell fraction increased with an increase of additional pressure, indicating that the relative resistance was changed according to the rate of PMN plugging and dislodging in the pores of the membrane.

Filtration↗
PubMed1989

[Effects of composite resin materials on gingiva and pulp].

Composite resin materials are now widely used for dental therapy. The purpose of this study was to clarify the effect of composite resins on gingiva and pulp in case of application of them for temporally splint in periodontal treatment. 60 teeth in 6 female dogs ranging between 1 and 2 years of age with healty teeth and gingiva were divieded to 4 groups; (1) 12 teeth, controls; (2) 12 teeth, self-cured composite resin (Clearfil F II, CF II); (3) 18 teeth, light-cured resin (Belfel LX, BLX), curing time 20 sec. and (4) 18 teeth, BLX, 40 sec., and then 48 class V composite resins were restored supragingivally. The experimental procedure were carried out for 5 days and 30 days. Histopathological observations of 60 teeth inclusive of controls were made by applying to specimens with Hematoxylin eosin staining. For the materials and time periods in this study it was found that; 1. Light-cured composite resin was superior to self-cured composite resin on handlings. 2. There were no significant differences in periodontium between the experimentals (BLX, CF II) and controls in 5 days. At the 30 days the histologic score showed more gingivitis for the experimental teeth than for the controls (BLX-40 greater than BLX-20 greater than CF II greater than Cont.). 3. At 5 days hyperemia occurred in some cases of experimentals (both BLX and CF II). The appearance of predentin and changes of odontblastic layer were observed slightly in 30 days. But there were no significant differences between BLX and CF II. 4. The result suggested that applying to composite resin materials for temporally splint, both gingiva and pulp have to be protected.

Animals↗
PubMed1989

[Effects on repaired bone with hydroxyapatite by the changes of dynamics in the alveolar bone].

Hydroxyapatite (HAP) is regarded as a useful material for grafting in procedure aimed at bone replacement. The purpose of this investigation, as a basic experiment, was to demonstrate bone formation in the dental extraction sockets during orthodontic movement of the neighboring teeth in the initial wound healing phase, and to clarify effects of indirect forces through alveolar bone on repairing bone in extraction sockets. Secondary we examined changes in the bone formation in the sockets during the tooth movement which were plugged with HAP granules and compared with the repairing bone without HAP. For this study seven dogs were used and were scarificed according to a schedule yielding observation periods up to 6 weeks. The animals were injected continuously with tetracycline during the experimental period. Undecalcified mesio-distal specimens 65-100 microns of thickness were prepared at first for microradiogram and then subjected to fluorescence microscopy. The observations indicated that the bone formation seemed to be accelerated with HAP implantation, however the alveolar trabeculae around HAP were developed during the tooth movement less than the control. The tooth movement in implanted sites was faster than in the sites without HAP implantation. The decreased response on alveolar bone formation, incident to experimental tooth movement into extraction sockets, was found in the pressure area, mesial part of socketswall. It might be induced by excessive stress during the tooth movement, amplified by the change of bone repairing due to the HAP implantation.

Alveolar Bone Loss↗
PubMed1989

[Analysis of 293 cases of hepatocellular carcinoma of recent ten years--I. Epidemiology, anamnesis and tumor occupying rate].

Two hundred and ninety-three cases of hepatocellular carcinoma (HCC) admitted to the key hospital of the rural area of western Japan, Saga Prefectural Hospital, during 10 years since 1979 to 1988 were analysed retrospectively. The male to female ratio was 3.7 to 1 and the ratio of HBs-Ag positive to negative was 3.5 to 1. The peak of the age distribution was seventh decade. The incidence increased annually, especially in HBs-Ag negative males. Their past history of blood transfusion was considered as an etiology of HCC in 19 (9.9%). The HCC was diagnosed approximately 10 years earlier in habitual drinkers than non-habitual drinkers of both positive and negative HBs-Ag. The incidence of small tumors is associated with the past history of chronic liver disease, negativity of HBs-Ag, lack of symptoms and old age.

Adult↗
PubMed1989

[Analysis of 293 cases of hepatocellular carcinoma of recent ten years--II. Diagnosis, therapy and prognosis].

Two hundred and ninety-three cases of hepatocellular carcinoma (HCC) of recent ten years during 1979 and 1988 were analysed on its diagnosis, therapy and prognosis. Angiography was the most useful diagnostic method for the first 5 years. During recent 5 years and for the tumor with size less than 2 cm, however, ultrasonography was the best method. 24.7% cases showed negative AFP and only 42.5% cases showed the level over 400 ng/ml. According to the tumor occupying-rate at the diagnosis, the number of cases of E1 had increased annually, the other cases being unchanged. 88.6% cases had liver cirrhosis microscopically as being reported previously. As a therapy TAE was most frequently performed, followed by operation, arterial infusion of antitumor drugs et al. The prognosis of the patients depended on the tumor occupying-rate. For the case of E1, the prognosis was the best by the therapy of ethanol injection therapy, operation and TAE. For the cases with tumor of larger than E1, frequent TAE was the best. From these results we concluded that we must make efforts to find small tumors to get the good prognosis.

Adult↗
PubMed1989

Hair aluminium in normal aged and senile dementia of Alzheimer type.

To investigate relationship between aluminium and senile dementia of Alzheimer type (SDAT), hair aluminium concentration was measured by ICP method in 35 cases of SDAT (mean 80 yr.) diagnosed clinically and 71 normal aged volunteers (mean 76 yr.). In normal aged, cerebral blood flow (CBF) also determined by Xe133 inhalation method simultaneously. Mean hair aluminium concentration in SDAT was within normal range of Japanese subjects and significantly lower than that of normal aged controls. There was no significant aging effect to hair aluminium concentration in both groups. Hair calcium and magnesium concentrations were significantly lower in SDAT than that of normal aged. Hair aluminium positively correlated to hair calcium and magnesium in SDAT. Hair aluminium negatively correlated to CBF, and CBF positively correlated to calcium and magnesium concentrations in hair in normal aged. Hair aluminium concentration does not appear to be of use in the diagnosis of SDAT. However, it is undeniable that decreased calcium and magnesium enhance selective accumulation of aluminium in the brain in SDAT. Inverse correlation between hair aluminium and CBF in normal aged suggests that aluminium might have some contribution to aging of the brain.

Affect↗
PubMed1989

[Intermittent intravenous high-dose cyclophosphamide therapy for advanced prostatic cancer with distant metastasis].

Twelve patients with advanced carcinoma of the prostate were treated with intravenous high-dose cyclophosphamide. All were hormone-resistant cases. At an interval of 3-4 weeks, cyclophosphamide was administered intravenously. The standard dosage of cyclophosphamide was 1,000 mg/m2 and a 10% lower dose was administered to patients with liver dysfunction, anemia and elderly patients. The results of 10 patients were evaluable. One case showed objective partial response, 1 case was stable and 8 patients showed objective progression according to the NPCP efficacy evaluation standard. The overall response rate was 20%, which we did not consider satisfactory. As to toxicity of cyclophosphamide, one patient died of severe acute hepatic failure, but in others, complications were mild to tolerable.

Adenocarcinoma↗
PubMed1989

[Effect of perfluorochemicals on experimental cerebral ischemia].

It has been noted that perfluorochemicals (PFC) which were developed as artificial blood substitutes, protect against ischemic brain injury by their ability to serve as oxygen carriers. It is also known that normovolemic hemodilution (HD) improves cerebral blood flow (CBF) and neurological symptoms in cerebral infarction. However, there are few reports concerning the effect of PFC on the collateral circulation via pial anastomoses in cases of middle cerebral artery (MCA) occlusion. The ability to record the pial arterial blood pressure (PAP) without interfering blood flow now makes it possible to measure the segmental resistance of cerebral vessels. By using this method, one can measure collateral vessel resistance through pial anastomoses following MCA occlusion. In this paper, we studied the protective effects of PFC combined with HD on ischemic brain injury with the focus on the collateral circulation via pial anastomoses following occlusion of the MCA. Twenty adult cats were studied: control, 8; HD, 5; Fluosol (Fluosol-DA), 7. The systemic arterial pressure (SAP) and PeCO2 were continuously monitored. Subsequently the MCA was occluded via the transorbital approach. CBF in the ectosylvian gyrus (central area of the ischemic lesion) was measured by the hydrogen clearance method. A small pial artery about 100 microns in diameter on the exposed ectosylvian gyrus was punctured nonocclusively with a micropipette filled with 2 M sodium chloride which was connected to a servo-null micropressure system (Model 900, W-P Instruments, Inc. U.S.A.). The electroencephalogram (EEG) was recorded from the ectosylvian gyrus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[Relation of surface texture of fine finishing diamond point for composite resin and polished surface of composite resin].

Distribution of diamond grain size of seven fine finishing diamond points was measured by a digital image analyzer. Also influence of diamond grain size of fine finishing diamond points on finished surface of two types of visible light cured composite resins (semihybrid type and submicron filler type) were investigated. Diamond grain size was almost from 10 to 100 microns 2 in area. Diamond grain size was closely related to the surface roughness of semihybrid type composite resin, although it was not related to that of submicron filler type composite resin. Surface roughness of a submicron filler type composite resin finished at a low speed was less than that at a high speed. Grain size of diamond point and revolution speed may play an important role in surface texture of composite resin.

Composite Resins↗
PubMed1989

Effect of haemodilution on experimental cerebral ischaemia.

The effect of normovolaemic haemodilution (HD) on cerebral ischaemia after middle cerebral artery occlusion (MCA) was studied. Thirteen adult cats (HD group, 5; control group, 8) were used. Systemic arterial pressure (SAP) was monitored continuously. MCA occlusion was produced by a transorbital approach. Regional cerebral blood flow (rCBF) in the ectosylvian region was measured by a hydrogen clearance method. The electroencephalogram (EEG) was monitored, and spectral power of the EEG was calculated. Pial artery pressure (PAP) in the ectosylvian region was continuously recorded non-occlusively by a micropressure recording device. In the HD group, low-molecular-weight dextran was given normovolaemically from 10 minutes after ischaemia to lower the haematocrit (Ht) to 24%. The rCBF values in the HD group were significantly higher than in the control group after 90 minutes. Upstream resistance [(SAP-PAP)/rCBF] was significantly lower in the HD group than in the control group. Furthermore, downstream resistance (PAP/rCBF) was significantly lower in the HD group than in the control group at the 180-minute point. There was no significant difference between the two groups in the spectral power of the EEG during ischaemia. The Ht was significantly correlated with rCBF in both groups. These results indicate that haemodilution can improve rCBF by lowering the Ht and improving the microcirculation of collateral vessels via pial anastomoses, although it might have insufficient effect on improvement of cerebral function.

Animals↗
PubMed1989

Anticonvulsant activities of 1-phenylcyclohexylamine and its conformationally restricted analog 1,1-pentamethylenetetrahydroisoquinoline.

1-Phenylcyclohexylamine (PCA), an analog of phenyclidine (PCP) in which the piperidine ring is replaced by a primary amino group, and its conformationally restricted analog 1,1-pentamethylenetetrahydroisoquinoline (PM-THIQ) were potent anticonvulsants in the mouse maximal electroshock (MES) seizure test (ED50 values, 7.0 and 14.3 mg/kg, respectively). At higher doses, the drugs caused motor impairment (TD50 values, 16.3 and 43.0 mg/kg) and blocked the behavioral effects and lethality of i.p. injected N-methyl-D-aspartate (NMDA) (ED50 values, 36.3 and 127 mg/kg). The separation in potencies in the MES seizure and motor toxicity tests of PCA and PM-THIQ contrasts with PCP which was equally potent in both tests. Several compounds that were structurally related to PM-THIQ (N-ethyl-PCA, 2-methyl-PCA, N-methyl-PM-THIQ, tetrahydroisoquinoline and benzylamine) also blocked MES seizures and caused motor impairment, but failed to show as great a separation between MES anticonvulsant activity and motor toxicity. None of the compounds protected against seizures induced by the chemoconvulsant pentylenetetrazol at doses that lacked motor toxicity. The drugs were also evaluated for their ability to displace [3H]-1-[1-(2-thienyl)-cyclohexyl]piperidine from binding to high affinity acceptor sites (presumably on NMDA receptor-coupled channels) in rat brain homogenates. The rank order of potencies in the binding assay was similar to that in the behavioral tests, except for 2-methyl-PCA which was behaviorally more potent than expected.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[Primary hyperparathyroidism in a child with parathyroid crisis--review of 24 cases reported in Japan].

A 9-year-old boy, who had been admitted to the Pediatric Department for the examination of IgA nephropathy, was transferred to our urological clinic on Aug. 6, 1985, because of parathyroid crisis. Before urological consultation, he had been complaining of bilateral knee and calcaneal pain, anorexia and abdominal pain, which had persisted for several days. Laboratory data indicated serum Ca of 17.6 mg/dl, iP of 2.3 mg/dl and iPTH of 0.77 ng/ml. Roentgenographic examination such as chest, extremities and neck computed tomography showed no abnormal findings. The final diagnosis was parathyroid crisis caused by primary hyperparathyroidism and neck exploration was carried out on August. 10. Left upper parathyroid gland, which was 1 cm in diameter, was surgically removed. The other three glands were normal in size. Histological examination of the resected parathyroid gland revealed chief cell adenoma. In the post-operative course, serum Ca level was soon reduced to the normal range and bone pain disappeared rapidly. During the follow up period of 2.5 years, the patient was clinically free of recurrence. Only 23 cases of primary hyperparathyroidism in children have been reported in the Japanese literature. The clinical characteristics of these specific cases are that primary hyperparathyroidism in children shows a low incidence of renal lesion, but the complicated bone disease is of higher incidence compared with the adult cases. Histopathologically, parathyroid adenoma was frequently observed (14/19), and the other 5 cases were parathyroid hyperplasia.

Adenoma↗
PubMed1989

[Foreign body in the kidney: a case report and a review of the Japanese literature].

A 50-year-old female was admitted to our hospital with the chief complaint of right lumbago. She had undergone acupuncture for right lumbago several years earlier. Radiography revealed a linear metallic shadow in the right kidney. Computed tomographic scan revealed it to be located in the right renal parenchyma. The foreign body was extracted operatively. Including our case, 43 cases of foreign bodies in the upper urinary tract found in the Japanese literature so far are reviewed.

Acupuncture Therapy↗