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Biomedical subjects

H Aoki

Publications and source records attributed to H Aoki.

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

[Coagulation and fibrinolysis in chronic subdural hematoma. Measurement of fibrinopeptides].

The pathogenesis of chronic subdural hematoma is not fully understood. It is thought that fibrinolytic hyperactivity within the hematoma capsule plays an important role. However, since this hyperactivity has not been found in the systemic blood, accelerated fibrinolysis is thought to occur only locally. To evaluate coagulant and fibrinolytic activities in the peripheral blood, the authors measured fibrinopeptide A (FPA) and fibrinopeptide B beta 15-42 (FPB beta), which are relatively sensitive hematologic factors, in 14 patients with chronic subdural hematoma. Peripheral venous blood was collected within 24 hours before surgery and FPA and FPB beta levels were determined. In the eight cases followed for more than 1 month after surgery, pre- and postoperative FPA and FPB beta values were compared. The possible relationship between preoperative FPB beta and hematoma density as well as elevated intracranial pressure (judged by preoperative computed tomography) was also examined. The following results were obtained: 1) Preoperative FPA and FPB beta values were both statistically significantly elevated suggesting systemic acceleration of coagulant and fibrinolytic activities. FPB beta levels exceeded those of FPA in almost all cases, indicating that fibrinolysis was more dramatically enhanced. 2) Many patients with high FPB beta values had high-density areas on computed tomography scans. 3) Patients with choked disc had high FPB beta values, suggesting a correlation between chronic intracranial hypertension and FPB beta. 4) Postoperatively, there was a marked decrease in FPA values, whereas FPB beta values remained above normal, which may reflect persistence of accelerated systemic fibrinolytic activity in patients with chronic subdural hematoma.

Adult↗
PubMed1989

Interposition of a saphenous vein graft for early recurrent carotid stenosis--report of two cases.

The main cause of recurrent stenosis within 24 months of carotid endarterectomy is myointimal hyperplasia. In these cases, reoperation is technically difficult because there is no true plane of dissection between the recurrent plaque and the remaining vessel wall. The authors present two cases of early recurrent stenosis after carotid endarterectomy, both of which were successfully treated by an interposed saphenous vein graft. In the first case, angiography suggested that the recurrent stenosis was due to atherosclerosis. In the second case, however, myointimal hyperplasia was suspected to be the cause, and this was confirmed by histological examination of the surgical specimen. The authors' experience indicates that anastomosis with an interposed saphenous vein graft is a reliably effective treatment for early recurrent carotid stenosis.

Arterial Occlusive Diseases↗
PubMed1989

Multiple meningiomas of the spinal canal and posterior fossa--case report.

The majority of multiple meningiomas are associated with von Recklinghausen's disease, and those that are not, i.e., true multiple meningiomas, particularly with simultaneous development in the posterior fossa and spinal canal, are very rare. We recently encountered a case of true multiple meningiomas in which the lesions were found simultaneously in the left posterior fossa and the upper thoracic spinal canal. The spinal meningioma consisted mainly of meningotheliomatous components, and that in the posterior fossa of fibroblastic components. Both tumors were surgically removed. The cause of the multiplicity in cases of true multiple meningiomas is unknown. Incidental multiplicity is a consideration when the number of tumors is relatively small. Spinal meningiomas are often undetected in the absence of neurological symptoms. However, even if von Recklinghausen's disease is not present, and particularly when more than two meningiomas have been discovered, the patient must be carefully examined for other tumors.

Aged↗
PubMed1989

Flow-cytometric DNA analysis and immunohistochemical measurement of Ki-67 and BUdR labeling indices in human brain tumors.

Cell proliferation potential was assessed by measuring the labeling indices of the monoclonal antibody Ki-67 and of 5-bromodeoxyuridine (BUdR), and the cellular deoxyribonucleic acid (DNA) content in 48 human brain tumors. The diagnostic and prognostic value of flow-cytometric DNA analysis was also evaluated using ethanol-fixed paraffin-embedded BUdR-labeled specimens; these were the same specimens as were used for measuring the BUdR and Ki-67 labeling indices. Both the Ki-67 and the BUdR labeling indices correlated with the degree of malignancy estimated from conventional histological preparations. The Ki-67 labeling index was 1.7 times greater than the BUdR labeling index. The relationship of DNA aneuploidy to the labeling indices or to morphology in cases of glioma was examined. All of the tumors with an aneuploid line corresponded to malignant glioma classified by histological criteria, although malignant glioma did not always show DNA aneuploidy. In addition, the cases with aneuploid lines showed high BUdR and Ki-67 labeling indices. The cell kinetic data, which indicate the biological character of tumors, allowed prediction of the prognosis of the patients with gliomas. In contrast, despite the presence of an aneuploid line, three of 13 meningiomas showed a benign histological pattern without an aggressive clinical course, and neither the Ki-67 nor the BUdR labeling index was high. These results indicate an unequivocal relationship between DNA aneuploidy and clinical behavior; in general, both labeling indices may prove to be objective indicators of the outcome of patients with brain tumors.

Aneuploidy↗
PubMed1989

FK409, a novel vasodilator isolated from the acid-treated fermentation broth of Streptomyces griseosporeus. I. Taxonomy, fermentation, isolation, and physico-chemical and biological characteristics.

FK409, a novel vasodilator with anti-platelet aggregation activity, has been isolated from the acid-treated fermentation broth of Streptomyces griseosporeus No. 16917, which was cultured on a medium containing NaNO3 for 4 days. FK409 was purified from the culture-filtrate by extraction with ethyl acetate after adjusting the pH to 3.0 with HC1, followed by silica gel chromatography. The molecular formula of this compound was determined to be C8H13N3O4. In vitro, FK409 showed a potent relaxation activity on noradrenaline induced contraction of rat aorta. In addition to the vasodilating activity, this compound also showed potent anti-aggregation activities towards rabbit platelets. In vivo, intravenously administered FK409 resulted in marked blood pressure lowering in rats.

Animals↗
PubMed1989

FK409, a novel vasodilator isolated from the acid-treated fermentation broth of Streptomyces griseosporeus. II. Structure of FK409 and its precursor FR-900411.

In a purification study of novel vasodilator FK409 from the fermentation broth of Streptomyces griseosporeus, we found the existence of FR-900411, a precursor of FK409 in the broth, suggesting that FK409 was derived from FR-900411 via a chemical reaction. We therefore isolated FR-900411 from the broth. The structure of FK409 and FR-900411 were determined to be 1 and 2 respectively, on the basis of spectroscopic and chemical evidence.

Alkadienes↗
PubMed1989

FK409, a novel vasodilator isolated from the acid-treated fermentation broth of Streptomyces griseosporeus. III. Reaction mechanism and synthesis.

FK409 (1), a novel vasodilator, is a semi-artificial fermentation product of Streptomyces griseosporeus No. 16917, which was cultured in a medium containing nitrate. And the acid-treatment of the broth is essential for the generation of FK409. FK409 was considered to be formed via a novel synchronous nitrosation-nitration reaction of FR-900411 (2) which was produced by the strain as a precursor of FK409. The conversion of FK-900411 to FK409 proceeded under acidic conditions with nitrite formed by microbial reduction of nitrate. Total synthesis of FK409 was achieved starting from (E)-2-ethyl-2-butenal (3) via a nitrosation reaction of FR-900411 (2) as a key step.

Alkadienes↗
PubMed1989

Flux growth and crystal structure of pyromorphite.

Single crystals of pyromorphite, Pb5(PO4)3Cl, were grown by standard flux growth technique with excess lead chloride used as the flux. Pyromorphite was first prepared by heating an intimate mixture of lead hydrogen phosphate and lead chloride in the molar ratio 6:4 at 100 degrees C for 1 h. A mixture of 60 wt% of pyromorphite and 40 wt% of lead chloride was heated at 850 degrees C for 15 h and then cooled at the rate of 3.4 degrees C/h. Hexagonal prismatic crystals of length 1 mm were obtained. The chemical composition has close to the theoretical value. The crystal is hexagonal, space group P6(3)/m with a = 9.9981(8), c = 7.344(1) A and Z = 2. The structure was refined to R = 0.058 and Rw = 0.053 with 502 independent reflections. The structure is in principal the same as that of barium chlorapatite; the chlorine ions occupy the (0, 0, 0) position.

Apatites↗
PubMed1989

[Ultrastructural changes induced in rat ameloblasts and enamel by NaF administration, especially the stages of transition and maturation].

Single subcutaneous injections of sodium fluoride (84 mg/kg NaF) were administered to male Wistar rats weighing 100 g each. After 6, 12, and 24 hours and then after 2 and 5 days, the animals were fixed by perfusion with a mixture of 2.5% glutaraldehyde and 2.0% paraformaldehyde; and their upper incisors were subjected to optical microscopy, microradiography, and electron microscopy. 1. Changes in ameloblasts in the matrix-formation stage: Large vacuoles and dark globules, which frequently appeared to be stacked within the cell, could be seen in the distal one-third of the ameloblast 6 hours after NaF injection. These globules and vacuoles disappeared 24 hours after injection. Distortion of the Tomes' processes and separation of the ameloblasts from the enamel surface too could be seen. The separated areas gradually expanded to form cystic cavities, which developed toward the end of the formation stage of amelogenesis. But these cavities never extended to ameloblasts in the transitional stage. 2. Changes in ameloblasts in the transitional stage: Transitional ameloblasts may be divided into 2 stages: the early transitional stage, during which the proximal portion of the Tomes' process persists, and the late transitional stage, during which all trace of the Tomes' process has disappeared and a basement membrane-like structure has been produced. The appearances of ameloblasts in these two stages altered after NaF injection. In the early transitional stage, 6 hours after the injection, large vacuoles and dark globules appeared in the distal portion of the cell. Similar to vacuoles appearing during the matrix-formation stage, these vacuoles and globules disappeared 24 hours after injection. Traces of the Tomes' process, however, persisted and assumed an irregular, wavy form. The adjacent enamel adapted to and interdigitated with the cel surfaces without a structure resembling the basement membrane. NaF injection caused slight changes in the late transitional stage: small vacuoles appeared at the distal ends of the cell and disappeared 24 hours later. 3. Changes in the ameloblasts in the enamel-maturation stage: Six hours after the injection, small vacuoles appeared at the distal portion of the cell close to the striated border which was poorly developed. These vacuoles disappeared, and the striated border resumed its usual features 24 hours after the injection. 4. Changes in the enamel: In the forming enamel, a calciotraumatic line consisting of hypermineralized and hypomineralized layers could be seen. Another hypermineralized line appeared at the enamel surface adjacent to the transitional stage. Electron microscopy showed that this hypermineralized layer consisted of crowded, disoriented, needle-shaped crystals.

Ameloblasts↗
PubMed1989

[Study of objective assessment for pathways in areas of intercuspal position during masticatory movements].

Masicatory function is the result of a highly complicated neuromuscular activity which coordinates in stomatognathie system. Functional directions of masticatory cycles in areas of intercuspal position (IP) were objectively evaluated on each stroke obtained through the Sirognathography Analyzing System (S. G. G./A. S.; Siemens, W. Germany). Twenty seven dantate subjects were selected at random from students and staff members of Kanagawa Dental College. A piece of chewing gum was given to each subject to masticate it for a minute on one side and on the other side respectively. A total of masticatory cycles were successively recorded into S. G. G./A. S.. A statistical analysis, the equal probability for ellipstical variations, was made on the angular measurements from opening and closing phases of each cycle within 3 mm from onset and terminus in areas of IP during masticatory movements. Four characteristic features of angular measurements are presented, namely, subjects who showed different types in position and forms by plotted angles within 80% of total amounts. The following results were obtained from this study. 1. Functional directions of masticatory cycles are clearly recognized in areas of IP from opening and closing phases during masticatory movements. 2. An application of the equal probability for ellipstical variations seems to be efficient for the functional analysis of masticatory cycles. 3. A classification of different types of plotted angles contributes to become a basis for diagnosis of masticatory function and occlusion.

Dental Occlusion↗
PubMed1989

[A clinical study of amino acid metabolism in cancerous hypoproteinemia--the role of branched chain amino acids (BCAA) and appropriate compositions of BCAA in parenteral nutrition].

In order to determine the nutritional effects of BCAA compositions in the treatment of cancerous hypoproteinemia, the appropriate ratio of I-leu: Leu: Val and the proportion of BCAA to Total Amino Acids were investigated. As for results, indices such as the serum albumin, the RBP and N-balance quickly recovered to normal levels when the ratio of I-leu: Leu: Val was 1.0:1.8:1.0 and the proportion o BCAA to TAA was 31%. These composition thus may be suitable for the treatment of cancerous hypoproteinemia.

Amino Acids↗
PubMed1989

[Study on the concentrations of 5-fluorouracil (5-FU), tegafur (ET) and uracil in bile: comparison of UFT or FT].

The serum and bile tegafur (FT), 5-fluorouracil (5-FU) and uracil levels after administration of UFT were assessed in 13 cases of malignant biliary tumor accompanied by biliary obstruction in comparison with FT alone. The serum and bile FT and 5-FU levels showed almost the same transition pattern in both groups, reaching to the plateau in 1-2 weeks and revealing cumulative effect by continual administration. Correlation was obtained between serum and bile levels except for 5-FU level in UFT group (p less than 0.05). Correlation between 5-FU and uracil was obtained in the serum in both groups (p less than 0.05), but no effect of uracil was observed. In bile, correlation was seen only in UFT group (p less than 0.05), and the effect of uracil was observed in bile 5-FU level.

Aged↗
PubMed1989

A novel monoclonal antibody (OPD4) recognizing a helper/inducer T cell subset. Its application to paraffin-embedded tissues.

A novel monoclonal antibody (MAb), OPD4, reactive with a helper/inducer (H/I) subset of T cells in formalin-fixed, paraffin-embedded tissue sections, has been identified through immunization with an activated H/I T cell line, namely DL40. The antibody is an IgG1 antibody and it recognizes an antigen with a molecular weight of 200 kd, corresponding to that of leukocyte common antigen. OPD4+/CD4+ T cells provided better help for pokeweed mitogen-stimulated polyclonal IgG production than OPD4-/CD4+ T cells. OPD4 recognized the H/I T cell subset even in paraffin-embedded tissue sections, but did not recognize nonhematopoietic cells, suppressor/cytotoxic T cells, B cells, monocytes in the peripheral blood, or other normal hematopoietic cells as examined by the flow cytometric and immunoperoxidase methods. Besides the lymphoid cells, OPD4 reacted with a number of histiocytes (epithelioid cells) in tissues from sarcoidosis and tuberculosis. For the neoplastic lesions, OPD4 reacted with approximately half of the cases of T cell lymphomas. Consequently, OPD4 may be useful for the diagnosis and study of malignant lymphomas and other related lesions.

Antibodies, Monoclonal↗
PubMed1989

[Analysis of recurrences of meningiomas following neurosurgical resection].

A clinical and pathological study of 124 surgically treated patients with intracranial meningiomas was carried out to evaluate factors influencing recurrence. The patients ranged in age from 8 years to 75 years. Thirty-five (28.2%) were males and 89 (71.8%) were females. Recurrences occurred in 18 patients, once in eleven, twice in six, four times in one. The period from first surgery to recurrence ranged from 5 months to 84 months (mean 29.9 months). Age, sex, site of tumor, surgical grading, and histology were selected as analytic factors. Simpson's classification was used as surgical grading. All the patients with recurrences were younger than 60 years old, and particularly in the patients who were younger than 40 years the recurrence rate was high. Mean age of the group with recurrence was 41.8 years, which was significantly younger than that of the group without recurrence (52.0 years). In the group with recurrence, ten were males and eight were females. The recurrence rate was 28.6% in males, and was 9.0% in females. Thus the recurrence rate was significantly higher for males than for females (p = 0.016). It also seemed that the period from first surgery to recurrence was earlier for males than for females. The patients with meningiomas at posterior fossa or sphenoid ridge often had recurrences, and the recurrence rate was 29.4% and 21.7%, respectively. But these recurrence rates were not significantly higher than those at other sites. On the contrary, no recurrences occurred at convexity, intraventricle, and olfactory groove.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Cerebral sparganosis mansoni--report of two cases].

Cerebral Sparganosis Mansoni is a very rare disease caused by a larva of Diphyllobothrium and so far, only two cases have been reported. Another two cases are presented in this paper. Case 1: A 64-year-old man was admitted presenting with hypovolition. He has eaten thunder fishes several years before. CT scan revealed an extensive low density area with an enhanced nodular mass around the right basal ganglia. An operation was carried out on the preoperative diagnosis of brain tumor and a granuloma was completely removed. His postoperative course was excellent. The histological examination confirmed the diagnosis of cerebral sparganosis. Case 2: The patients was 60-year-old male showing hypesthesia in the left half of his face. He has often been to South Korea where patients of Sparganosis Mansoni are often reported. Enhanced CT scan demonstrated a small nodular region in the tip of the left temporal lobe. Sparganum Mansoni was identified during surgery and a granuloma was also extirpated. His postoperative course was also excellent. In cases with cerebral parasitism by Sparganum Mansoni, CT scan shows an extensive low density area with a nodular enhancement, but no calcification nor cyst formation. It is quite difficult to differentiate sparganosis from cerebral tumors on CT and laboratory data preoperatively. The diagnosis is usually confirmed by postoperative histological examination. As for the treatment of this disease, no effective chemotherapy is now available and surgical excision is recommended. Actually, four cases with cerebral sparganosis including two of our own demonstrated a satisfactory prognosis by surgical treatments.

Animals↗
PubMed1989

[A clinical evaluation of AMS 700 penile prosthesis in the treatment of impotence].

The AMS 700TM & 700 CXTM penile prosthesis was implanted in 34 organic and mixed-type impotent patients between November, 1984 and July, 1988. The patients' ages ranged between 32 and 70, with an average age of 57.2. Twelve weeks after implantation, the prosthesis was evaluated in terms of patient satisfaction with sexual intercourse and postoperative complications. Twenty three patients (67.7%) were highly satisfied, 7 (20.3%) satisfied, 3 (8.8%) dissatisfied and 1 patient worsened (2.9%). Severe complication was found in two cases, both of them being complicated by infection; as a result the prosthesis was removed. Utility of the prosthesis, e.g. effectiveness and safety was; high utility in 26 cases (76.5%), moderate utility in 7 cases (20.6%), and no favorable in one case (2.9%). Thus, overall effectiveness and safety of the AMS 700 penile prosthesis, with its excellent cosmetic appearance upon implantation, were demonstrated by the above findings.

Adult↗
PubMed1989

[Productive aspergilloma on the inner wall of a cavity].

Fungus ball type pulmonary aspergilloma is easily recognizable on chest X-ray. This is a report on "productive aspergilloma on the inner wall of a cavity" (PAIC), named from our clinical experience in 1980, which grew to form aspergillus strata on partial or overall inner walls of the cavity. Our 5 cases with this type supported the existence of this type and revealed an 18% incidence in patients with pulmonary aspergilloma, characteristic clinical features and immunological reactions, thus pointing to the necessity of early diagnosis and treatment for this type of aspergilloma. The species of aspergillus cultured from the patients with this type of disease was Aspergillus fumigatus.

Adult↗