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Y Isobe

Publications and source records attributed to Y Isobe.

At least 127 records · Page 7Linked to original sources
PubMed1989

[Localization of pancreatic insulinomas by combined radiographic methods].

Seventeen cases with a total of eighteen insulinomas were examined by ultrasonography (US), computed tomography (CT), angiography, percutaneous transhepatic portal and pancreatic venous sampling (PTPS) and intraoperative ultrasonography (IOUS). We discussed about diagnostic accuracy of insulinomas on these diagnostic modalities. Tumor localization was achieved by US in 39%, CT in 72% and angiography in 81%. Although total 15 tumors (83%) can be correctly detected, multiple lesions were not completely ruled out. We recommended the criteria in PTPS as follows: Insulin concentration level above 200 mu U/ml. Or, both of insulin concentration ratio (step-up site/control) above three and elevation of the CPR concentration level on the PTPS. According to these criteria, the accuracy rate was 91%. Overall preoperative diagnostic accuracy was 100%. IOUS allowed us to detect the localization of the tumors completely.

Adenoma, Islet Cell↗
PubMed1989

[Preoperative radiotherapy of bone and soft tissue sarcomas].

UNLABELLED: The role of preoperative radiotherapy was evaluated in 16 cases with soft tissue sarcoma and 13 cases with osteosarcoma. Nine osteosarcoma cases underwent radiotherapy of whole lesion, and 4 cases had radiotherapy only of the surgically incurable portion. There were no local recurrences in M0 cases, but skin necrosis occurred in the whole radiation group. As for the soft tissue sarcomas, local recurrence was not seen in virgin cases, but two cases which had received previous treatment showed local recurrence. There were no cases with severe side effects. CONCLUSION: 1. Partial radiotherapy was effective as preoperative treatment for osteosarcoma. 2. preoperative radiotherapy is better than postoperative radiotherapy from many standpoints.

Adolescent↗
PubMed1989

[Evaluation method of surgical margin in musculoskeletal sarcoma].

The evaluation of surgical margin is useful in determining the curability of surgical treatment of musculoskeletal sarcoma and the degree of possibility to reduce later surgery as part of preoperative therapy. However, at present there has been no worthwhile evaluation method developed for these purposes. In this paper we propose a new evaluation system for surgical margin as drafted by the Bone and Soft Tissue Tumor Committee of JOA. This system was applied in 197 cases at the Cancer Institute Hospital to determine the clinical significance in the treatment of musculoskeletal sarcoma. In this method, surgical margin was classified into four types according to the distance between the surgical margin and the reactive zone of the tumor. The types of surgical margins (in order of surgical extent) are curative margin, wide margin, marginal margin, and intralesional margin. Surgical margin is said to be curative if the margin is more than 5cm outside the reactive zone. It is referred to as wide if the margin is less than 5cm and marginal if the margin is at the reactive zone. In our evaluation, a thin barrier is estimated as a 2cm thickness of normal tissue, a thick barrier as a 3cm thickness of normal tissue, and joint cartilage as 5cm thickness. Moreover, in all cases the surgical margin is considered to be curative if the margin is outside a barrier and there is normal tissue between the barrier and the reactive zone of the tumor. The results of the study were as follows.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Neoplasms↗
PubMed1988

Three-dimensional immunogold localization of alpha-actinin within the cytoskeletal networks of cultured cardiac muscle and nonmuscle cells.

The ultrastructural distribution of alpha-actinin was studied in cultured hamster heart cells by immunogold replica electron microscopy. This technique enabled us to localize alpha-actinin within the cytoskeletal networks at high resolution and in three dimensions. Colloidal gold, indicating the presence of alpha-actinin, was localized on the Z bands of nascent myofibrils in myocytes and on stress fiber bundles in nonmuscle cells. alpha-Actinin staining was also seen on stellate foci, where cytoskeletal filaments converged along the inner myocyte cell membranes. Intermediate filaments were associated with Z bands of myofibrils, stress fibers, and subplasmalemmal actin networks at the specific points where alpha-actinin was localized on these structures. Heavy meromyosin treatment prior to immunostaining confirmed that the thin filaments contained actin. These results suggest that alpha-actinin serves to interlink these various cytoskeletal elements. In addition, this protein may be involved in the initial phases of filament organization during myofibrillogenesis along the inner surface of the myocyte plasma membrane.

Actinin↗
PubMed1988

[Recently experienced ten cases of insulinoma--preoperative diagnosis of localization and intraoperative simultaneous monitoring of glucose and insulin].

We have experienced 10 cases of insulinoma during the last 10 years from 1977 to 1986. All cases had strong hypoglycemic symptoms such as disturbance of consciousness, and insulinoma still tended to be misdiagnosed as epilepsy. The diagnosis of insulinoma was easily available from serum IRI (immunoreactive insulin)/plasma glucose ratio in all of the ten cases. As preoperative procedures for the diagnosis of localization, arteriography, computed tomography and portal blood sampling were positive in 6 of 8, 4 of 6 and 2 of 2 patients, respectively. At operation, all insulinomas could be identified by digital palpation. We performed simple excision of the tumor in 6 patients and distal pancreatectomy in 4 patients. The tumors were solitary and benign in all patients, ranging in size from 1.0 cm to 4.5 cm. Three cases were presented as case reports. In these cases, portal blood sampling and/or intraoperative monitoring of plasma glucose and serum IRI were performed. Portal blood sampling was effective even for a case which was negative in image diagnostic procedures. Furthermore, simultaneous monitoring of plasma glucose and serum IRI by quick radioimmunoassay seemed to be a good guide to the completeness of resection of insulin producing tumors.

Adenoma, Islet Cell↗
PubMed1988

[Pharmacodynamic study of the in vitro clonogenic assay--with reference to dose levels].

To determine the optimal condition of the clonogenic assay, the antitumor activities of 5-fluorouracil (5-FU) in vitro and in vivo were investigated from a pharmacodynamic viewpoint using 8 human carcinoma xenografts. The clonogenic assay was performed by the continuous exposure method, and the antitumor effects were evaluated by the colony survival rates (T/Cs). The in vivo experimental chemotherapy was also performed by the nude mouse system, and the results were evaluated by the T/C ratios of the tumor weights. For pharmacokinetic analyses, the area under the concentration curves (AUCs) of 5-FU in vitro and in vivo were computed. The T/Cs of 5-FU were highly correlated to the AUCs both in vitro and in vivo. By using these AUC-T/C correlations, the concentration of 5-FU in the clonogenic assay to predict the T/C of the maximum tolerated dose in mouse was calculated to be 3 micrograms/ml mathematically. This concentration was then verified by the clonogenic assay, where T/Cs in vitro could successfully correspond to the T/Cs in vivo. (The predictable rate was 87.5%) From these results, this pharmacodynamic comparison between in vitro and in vivo chemosensitivities was thought to be a promising method for determining the conditions of the clonogenic assay.

Animals↗
PubMed1988

[Procedures and results of limb salvage surgery of musculoskeletal sarcoma].

During the 8-year period beginning 1979, 116 cases of musculoskeletal sarcoma were treated by limb salvage operation. Of these, the local recurrence rate was 9% and the postoperative metastatic rate was 28%. The limb salvage rate was about 80%. Limb salvage procedures were generally performed using curative surgical procedures without preoperative adjunctive therapy. However, reduction of the surgical margin to achieve local cure was made possible by combined therapy with preoperative adjunctive chemotherapy or radiotherapy. The wide procedures combined with preoperative adjunctive therapy achieved a local curability rate equal to curative procedures. Marginal procedures following preoperative radiotherapy were also undertaken in those cases in which the tumor was located in an area for which curative or wide procedures were not feasible. Also, similar procedures were performed for patients of advanced age, patients with lung metastasis, patients who refused ablative surgery, and for extirpation of lymph node metastases. Accordingly, we were able to determine which procedures best ensure local curability. Also, the most significant prognostic factor was found to be local recurrence caused by inadequate surgical margin. This was especially true in the treatment of high malignant sarcoma. Moreover, from analysis of recurrent cases, the suggested factors contributing to local recurrence were: the invasive character of the tumor, lymph node metastasis, skip metastasis, tumor dissemination due to pathological fracture, previously performed inadequate surgery, venous invasion, and multicentrical occurrence of certain tumors.

Adult↗
PubMed1988

[Surgical treatment for bone and soft tissue sarcomas of the shoulder part].

Since 1977 we have treated 18 bone sarcomas and 16 soft tissue sarcomas of the shoulder part. For 10 bone sarcomas of the proximal humerus, four fore-quarter amputations, two curative wide resections, and four wide excisions were performed as radical operations. The reconstructive procedures after the six resections were two spacer insertions, one total shoulder replacement, and three arthrodeses with autografts. Considering the functional result, the arthrodesis is the most-recommended method. For eight bone sarcomas of the scapula, three total resections and four partial resections of the scapula, and one debulking operation were performed. For 16 soft tissue sarcomas, we performed two ablative operations, three curative wide resections, five wide excisions, and six conservative operations after adjunctive chemo-and/or radiotherapy. Among all 34 bone and soft tissue sarcomas, the success rate for limb salvage was 74%, while the recurrence rate was 18%. The functional result of the limb salvage operations was far better than that of ablative operations of the shoulder part. In fact the rate of satisfactory ADL (excellent and good) was 81% among the limb salvage cases, while for ablative operations, the ADL ratings were all poor.

Bone Neoplasms↗
PubMed1987

Cell kinetic analysis of human tumor xenografts using anti-bromodeoxyuridine monoclonal antibody.

The cell kinetics of human tumor xenografts serially transplanted into nude mice was examined using bromodeoxyuridine (BrdU) and anti-BrdU monoclonal antibody. After various doses of BrdU were given intraperitoneally into tumor bearing nude mice, the tumors were resected and stained immunohistochemically, using the anti-BrdU monoclonal antibody. The number of stained cells was demonstrated as the labeling index (LI). The optimal condition for BrdU staining was assumed to be 300 mg of BrdU per kg followed by an incubation period of one hour. Since the LI by BrdU closely correlated with that in autoradiography by 3H-TdR, this method is more useful and safer than the conventional autoradiographic study for investigating clinical cell kinetic analysis, as there is no need to use potentially hazardous radioactive compounds and the period of assay is shorter.

Animals↗
PubMed1987

[Anti-inflammatory, analgesic and anti-pyretic activities of a new anti-inflammatory compound, 2-[4-(3-methyl-2-butenyl)phenyl] propionic acid (TA), in experimental animals].

Anti-inflammatory, analgesic and anti-pyretic activities of orally administered TA were investigated in experimental animals. Against acetic acid-induced vascular permeability in mice, carrageenin-induced hind paw edema in rats and ultra-violet ray-induced erythema in guinea pigs, TA produced a dose related inhibition at doses of 40-160 mg/kg, 10-40 mg/kg and 10-40 mg/kg, respectively. TA produced no inhibition against histamine-induced vascular permeability even at a dose of 200 mg/kg in rats. Cotton pellet-induced granuloma and adjuvant-induced arthritis in rats were significantly inhibited by repeated administration of TA at a dose of 50 mg/kg/day for 6 days and 25 mg/kg/day for 6 days, respectively. TA showed a dose related analgesic effect at a dose of 50-200 mg/kg in acetic acid writhing, Randall-Selitto and adjuvant arthritic pain methods. A high dose of TA was needed to produce an analgesic effect in the pressure method using mice. TA produced an anti-pyretic effect against the pyrexia induced by yeast in rats. On the other hand, TA showed no effect against normal body temperature in rats. These results suggest that anti-inflammatory, analgesic and anti-pyretic activities of TA are generally a little weaker than those of ibuprofen, and the mode of action of TA is similar to that of a typical acidic non-steroidal anti-inflammatory drug such as ibuprofen, indomethacin or phenylbutazone. The ulcerogenic activity of TA was about 2 and 4 times weaker than that of ibuprofen in rats and mice, respectively. TA showed a protective effect against gastric necrosis induced by HCl.(ABSTRACT TRUNCATED AT 250 WORDS)

Analgesics↗
PubMed1987

Pharmacodynamic aspects of in vitro and in vivo chemosensitivity tests.

To determine the optimal conditions for clonogenic assay, the antitumor activities of 5-fluorouracil (5-FU) in vitro and in vivo were compared from a pharmacodynamic viewpoint in a human carcinoma xenograft-nude mouse system. In the clonogenic assay, tumor cells were exposed to 5-FU continuously for 2 weeks, and the results of the assay were evaluated in terms of colony survival rates (T/C). Tumor-bearing BALB/c male nude mice were treated with 5-FU, and the results were evaluated in terms of the lowest values of relative mean tumor weights (T/C). To compute the area under the curve (AUC) after administration of 5-FU in vitro and in vivo, agar and serum levels of 5-FU were measured by bioassay. Antitumor activities in terms of T/Cs against a gastric carcinoma strain (H-111) depended highly on the AUCs in vitro and in vivo. The T/C in vitro (z) was correlated with the AUC in vitro (w), z = 58.4 x 0.99331w, and the T/C in vivo (y) was also correlated with the AUC in vivo (x), y = 52.1 x 0.88552x. On the assumption that the T/Cs of these two regression equations were equivalent (y = z), a correlation between w and x was derived. To predict the T/C at the maximum tolerated dose of 5-FU in mice, the optimal drug concentration in vitro was calculated to be 2.7 micrograms/ml, which also proved to be suitable for seven other carcinoma strains. Our experimental system was thought to be adequate for selecting the optimal drug concentration in the clonogenic assay.

Animals↗