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Biomedical subjects

S Kikuchi

Publications and source records attributed to S Kikuchi.

At least 397 records · Page 22Linked to original sources
PubMed1989

Stannous fluoride and its effects on oral microbial adhesive properties in vitro.

The effect of sodium and stannous fluoride compounds on the coherence of Streptococcus mutans was examined. Both commercial and reagent grade preparations were tested on S. mutans, strain 6715. Test fluoride aliquots at various concentrations were added to sucrose suspensions of S. mutans at a starting microbial suspensions equivalent to 25% transmission as read in a spectrophotometer. Test samples were rotated at 35 degrees, 80 rpm in an incubated orbital shaker. Analysis at 560 nm at various time periods, was performed to determine increases in %T as a function of aggregate formation. SnF2 preparations routinely inhibited coherence at concentrations as low as .001%, whereas NaF showed no effects on microbial cell-to-cell coherence.

Bacterial Adhesion↗
PubMed1989

[Experimental study on the effect of replantation of immature permanent teeth on the periapical and periodontal tissues].

Replantation and semi-rigid fixation were performed on canine immature permanent teeth, and one week after replantation the teeth were treated by root filling with calcium hydroxide. The root apex and periodontium of the teeth with replantation were examined for changes regularly during the experiment by microradiographic, fluorescence microscopic, polarizing microscopic and X-ray observation of undecalcified horizontal continual ground sections. The results obtained were as follows: 1) Immediately after replantation, root formation was observed, but its formation was found to cease at a relatively early time. No site of the root showed any inflammatory resorption. 2) The dentine of the teeth with replantation was narrow, and the whole tooth substance showed discoloration due to penetration of calcium hydroxide. 3) the periodontal space surrounding the teeth with replantation was decreased daily by new bone actively formed from the alveolar bone proper and by a thin cementum layer added on the periodontal surface. This change occurred from one week after replantation. 4) The width of the periodontal space of the teeth with replantation, which had been wider than that of a control tooth, was increased and decreased daily at the cervix and root apex and the central part of the root, respectively. 5) Collagen fibers of the periodontal membrane were present in the periodontal space of the teeth with replantation, together with regeneration of the periodontal membrane that had been cut by extraction. 6) There were no changes due to replantation in the two teeth adjacent to the tooth with replantation or the lateral jaw.

Cuspid↗
PubMed1989

[A case of successful repair of a left subclavian arterial aneurysm ruptured into the esophagus--review of 89 cases in Japan].

This report concerns a case of a left arteriosclerotic subclavian arterial aneurysm ruptured into esophagus. A 61-year-old man who complained of fever, dyspnea, and dysphagia was diagnosed by chest X-ray, selective left subclavian arteriogram, and chest CT. Because he vomited a large amount of blood before an operation, we suspected that the aneurysm had ruptured into the esophagus, and therefore performed an emergency operation. The operative procedure consisted of exposing the aneurysm through a median sternotomy incision with the addition of a left supraclavicular incision, proximal and distal ligation, and reconstruction of blood flow by an aorto-left subclavian artery bypass with a Gore-tex prosthetic graft; however the aneurysm was not resected because of adhesion to the surrounding tissues. The post-operative course was uneventful and the patient is now normal and back at work, 2 years after the operation. Subclavian arterial aneurysms are relatively rare among peripheral arterial aneurysms. The common causes of subclavian aneurysms are arteriosclerosis (18%), trauma (14.6%), non specific inflammation (13.5%), and thoracic outlet syndrome (11%). Of the only 15 ruptures in 89 cases that have been reported in Japan, none have ruptured into the esophagus. Subclavian artery aneurysms represent a risk of rupture or peripheral circulatory failure, and consequently, should be considered for surgical treatment.

Aneurysm↗
PubMed1989

[An immunohistological study of local immunity of colorectal cancer].

The surgical specimens from forty-two patients with colorectal cancer were studied by the immunoperoxidase method for immunoglobulin (Ig); the number of Ig containing cells and round cells within the lamina propria adjacent to the tumor was calculated. The results were as follows; 1) Population per 0.025 mm2 of IgA, IgM, IgG containing cells in the adjacent part to the tumor were 15.5 +/- 0.9, 13.6 +/- 1.4, 8.9 +/- 0.4, respectively. 2) IgA containing cells in the adjacent part to the tumor decreased in number compared with the histologically normal part, while IgG containing cells were more frequently observed in the adjacent part. The differences were statistically significant (p less than 0.05). 3) The number of IgG containing cells was closely related to the size of the tumor, and IgM containing cells was in proportion to the presence of the lymph node metastasis. 4) The number of IgG containing cells in the adjacent part differed significantly between rectal cancer and colon cancer; the number being fewer in rectal cancer. 5) The round cells within the adjacent part increased in number, compared to the histologically normal part, and were observed to be more numerous in the localized ulcerative type of cancer than in the invasive ulcerative type. From these results it could be concluded that Ig containing cells play an important role in the local immunity of colorectal cancer.

Adult↗
PubMed1989

[How can we make mass-screening of stomach cancer more efficient using epidemiological results?].

From an observation of personnel we expect epidemiological studies make mass-screening of stomach cancer more efficient and suppose they should be done as to following aspects: (1) To decide the most efficient interval of mass-screening, investigating the frequency distribution of "Saving Duration" on many stomach cancers that is the duration when a stomach cancer is both detectably by screening and curable. (2) To decide who should undergo stomach examination quantifying cancer-risks of individuals with the use of epidemiological results. (3) To make epidemiological studies more sensitive and useful, classifying stomach cancers by microscopic pathological type, macroscopic one or "Saving Duration". (4) To settle a statistical standard of epidemiological results which is demanded for them to be useful in mass-screening.

Adult↗
PubMed1989

[A long-term follow-up study of the histologically confirmed chronic liver diseases in the Juntedo University Hospital].

In order to calculate the survival rate and elucidate the risk factors of liver cancer, 1,034 patients of the chronic liver diseases were followed up for 7.1 years of average. All patients were confirmed histologically from 1973 to 1982 in Juntendo University Hospital as liver cirrhosis (367), liver fibrosis (27), and chronic hepatitis (640). Until the end of 1986, 244 cases were died including 52 cases of liver cancer. The 10 years survival rate by Kaplan-Meier's method ranged from 39.85 for male liver cirrhosis to 80.64 for male chronic hepatitis. The results of proportional hazard model for male liver cirrhosis revealed that drinking alcohol affected negatively to the death from liver cancer, and that cigarette smoking and no history of operation due to portal hypertension affected slightly to it and that HBs antigen, history of blood transfusion and history of acute hepatitis almost have no relation to it.

Alcohol Drinking↗
PubMed1989

[Quantitative analysis of myocardial revascularization on left ventricular diastolic function].

To evaluate the effects of myocardial revascularization on left ventricular diastolic function, we studied three groups of subjects. Group I consisted of 10 patients without any previous myocardial infarction. Group II consisted of 10 patients with previous myocardial infarction. The control group consisted of 8 normal subjects, all with no evidence of cardiac disease as determined by cardiac catheterization. Left ventricular diastolic function was assessed by maximum negative dp/dt, constant T, diastolic compliance and 1/3 fractional filling before and after surgical revascularization. (1) Constant T, maximum negative dp/dt and diastolic compliance: There was no significant difference among groups I, II and the control group preoperatively, and the variables were not improved postoperatively. (2) 1/3 fractional filling: 1/3 fractional fillings in groups I and II were significantly lower (p less than 0.05, p less than 0.01) than the control group preoperatively, and it was significantly improved in group I, but unchanged in group II postoperatively. In conclusion, myocardial revascularization improves left ventricular diastolic function in the patients without previous myocardial infarction. The effects of myocardial revascularization, however, in the patients with prior myocardial infarction do not bring about an enhancement of left ventricular diastolic function.

Adult↗
PubMed1989

[Total graft replacement of the thoracoabdominal aorta with reconstruction of visceral branches, intercostal and lumbar arteries in expanding chronic dissecting aneurysms of the thoracoabdominal aorta].

Four patients with expanding chronic dissecting thoracoabdominal aneurysm underwent total replacement of the thoracoabdominal aorta with reconstruction of all visceral branches, intercostal and lumbar arteries with the aid of femoro-femoral bypass. During aortic cross-clamping, selective celiac and both renal arteries perfusion was performed to prevent the organ ischemia. Somatosensory evoked potentials monitoring or spinal cord evoked potentials monitoring was also performed to detect the spinal cord ischemia. Surgical technique employed in this series was direct anastomosis of onlay patch graft to the normal true lumen from which visceral branches and intercostal and lumbar arteries arise. The celiac artery and left renal artery arise from the false lumen in some cases were reconstructed with graft interposition or direct anastomosis to an opening made in the onlay patch graft. All patients survived the operation, and are leading normal life late in the postoperative period except one who developed partial paraplegia. Total graft replacement of the thoracoabdominal aorta may be a valid technique for the treatment of expanding aneurysms of the dissecting thoracoabdominal aorta.

Adult↗
PubMed1989

[Clinical effects of denopamine in patients with cardiac operations].

Denopamine is a new, orally active, positive inotropic agent. We evaluated its clinical effects in 13 patients who had undergone cardiac operations, 8 were in early postoperative periods and 5 were in late postoperative periods. In the former, denopamine therapy (30 mg/day) were started on the 6-14 th postoperative day in 5 patients so that they might free from catecholamine drip infusion (2-14 micrograms/kg/min), and on the 14-24th postoperative day in 3 patients in order that pleural effusion might reduce. All 5 patients were weaned from catecholamine, and pleural effusion in 3 patients disappeared completely. In the latter, denopamine therapy were indicated so that they might get relief from the symptoms of chronic heart failure. Although they had undergone combined valvular operations, they still remained in NYHA class II or III postoperatively, associated with cardiomegaly, hepatomegaly and atrial fibrillation. Denopamine therapy (15-30 mg/day) were quite effective in improving subjective symptoms but not in reducing cardiomegaly or hepatomegaly. No clinically significant side effects were noticed during 9-14 months of denopamine therapy. We conclude that denopamine is a quite useful cardiotonic agent in the postoperative management of patients with cardiac surgery.

Adult↗
PubMed1988

Combined contrast studies in lumbar spine diseases. Myelography (peridurography) and nerve root infiltration.

Successive performances of the morphologic and functional diagnostic procedures of myelography and/or peridurography along with nerve root infiltration were attempted for evaluating lumbar spine disorders with radicular symptoms. With this combination, the compressed area of the involved nerve root can be specified morphologically and the responsible root level can be assessed functionally. Physical examinations and the above procedures showed that there are three types of cases: cauda equina, radicular, and mixed; and that the responsible level is usually single. The type of decompression procedure can be predetermined, and the extent of decompression can be minimized by the specification of the responsible level and the type of nerve involvement. Symptoms improved in all operated cases after surgery.

Adult↗
PubMed1988

Relationships among genes and gene products of bacteriophage BF23.

Twenty-five gene products of bacteriophage BF23 were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their functions were studied in relation to type I and II genes classified by means of genetic complementation tests. All the type I mutants were defective in the synthesis of a tail protein, L3. In addition, 4 type I gene products, L5 (gp21), L7 (gp20), L8 (gp29), and L9 (gp25), were identified as constituents of tails (gp21 denotes that a protein is a product of gene 21). Three type IIb mutants in genes 10, 14, and 19 diminished substantially the production of late proteins, including tail and head proteins, and the two other type IIb mutants in genes 1 and 2 were defective in the synthesis of both early and late proteins. Of 14 type IIa mutants, at least 6 were defective in phage DNA synthesis and 2 were defective in the synthesis of head proteins. The defect in the head donor activities of type IIa mutants in extract complementation tests was due to the failure of the formation of mature heads containing DNA. The above results support directly the results of the genetic characterization of BF23 genes.

Autoradiography↗
PubMed1988

Regulation of the temporal synthesis of proteins in bacteriophage BF23-infected cells.

Regulation of temporal synthesis of pre-early, early, and late proteins in bacteriophage BF23-infected cells has been studied by using five amber mutants defective in genes 1, 2, 10, 14, and 19. The synthesis of pre-early proteins is negatively regulated by the actions of gene 1, a pre-early gene. The switch from pre-early to early protein synthesis is mainly regulated by the second-step DNA transfer reaction, which is controlled by at least genes 1 and 2. Early proteins can be kinetically and genetically divided into two regulatory classes, designated Ea and Eb. The shutoff of Eb-early protein synthesis is associated with the turn-on of late protein synthesis. This step is controlled by genes 10, 14, and 19. Gene 10 also regulates negatively the synthesis of Ea-early proteins, indicating that this gene has a dual function in the regulation of early protein synthesis. The temporal synthesis of phage-encoded proteins is regulated mainly at the transcriptional level. Evidence is presented indicating that the host RNA polymerase is modified by the interaction with the gene products of genes 2, 10, and 14 (gp2, gp10, and gp14, respectively). gp2 interacts with the enzyme in the earlier stage of infection but is replaced by gp10 in the later stage. This exchange reaction depends on the presence of gp14 and gp19 and is related to the switch from Eb to late protein synthesis. Thus, the regulation of BF23 gene expression occurs in a coordinated manner throughout the development of this phage.

Autoradiography↗
PubMed1988

Audiological characteristics of hearing loss following meningitis.

Meningitis is one of the leading causes of acquired sensorineural hearing loss in childhood, and many retrospective and prospective studies and case reports have been published. However, they have seldom discussed the nature of postmeningitic hearing loss from the audiological point of view. This study reports the results of audiological examinations performed on 5 patients suffering from hearing loss following meningitis. Extremely poor word discrimination scores as compared with pure-tone audiograms were common in all 5 cases. Type IV Békésy tracings were observed in 2 cases. Discrepancies between pure-tone audiograms and subjective hearing sensation and between pure-tone audiograms and ABR recordings were noted in 2 cases. These results suggest that varying degrees of retrocochlear involvement complicating the inner ear damage are the audiological characteristics of hearing loss following meningitis.

Audiometry, Evoked Response↗