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Biomedical subjects

T Okamura

Publications and source records attributed to T Okamura.

At least 595 records · Page 33Linked to original sources
PubMed1988

Results of resection of gastric cancer extending to adjacent organs.

We report the late results of resection in 281 patients with gastric carcinoma extending to adjacent organs. In 92 without incurable factors (peritoneal dissemination, liver metastasis and widespread nodal involvement) the 5-year survival rate was 36.7 per cent in those treated by gastrectomy and complete removal of the invaded organ. This value is significantly higher than the 17.4 per cent recorded in those undergoing gastrectomy alone or with incomplete removal of the invaded organs (P less than 0.05). In 189 patients with incurable factors, the 5-year survival rates were 5.4 and 2.8 per cent respectively in cases of complete and incomplete excisions. This tendency was similar in patients with a single invaded organ and also in those with plural organ involvement. In potentially curable patients treated by complete excision, the probability of long-term survival was statistically better than that following incomplete excision only when the pancreas was involved (P less than 0.05). We recommend complete excision of invaded organs, irrespective of the number or site of organs involved, provided that there is no evidence of incurable factors.

Colonic Neoplasms↗
PubMed1988

The renin-angiotensin system: an overview of its intracellular function.

The enzyme renin has been purified and characterized by structural analysis. Pure renin protein was used to produce a specific antibody to renin, which was useful in demonstrating the presence of a specific renin in many tissues other than kidney. Further, in these cells angiotensins I and II and converting enzyme all were found to coexist with renin by immunohistochemical studies, indicating the local production of renin, angiotensinogen and angiotensins in these cells. Angiotensin II produced in the cultured cells was secreted to the outside of the cells. Secretion of angiotensin II from the angiotensin-producing cells was demonstrated with perfused mesenteric artery. The secretion of angiotensin II from the vascular beds was inhibited by converting enzyme inhibitors, and was stimulated by the adrenergic beta-agonist isoproterenol. These studies demonstrate local production and controlled secretion of angiotensin II and define its physiologic role.

Angiotensin II↗
PubMed1988

The microvascular architecture of human malignant glioma. A scanning electron microscopic study of a vascular cast.

The three-dimensional microvascular architecture of human glioma was investigated. The results of the study, the first of its kind, suggested that the process of vascularization in glioma is based on two patterns. In a large proportion of the glioma, one pattern is similar to the vascularization observed in normal developing fetal and newborn rat brain, while in a small proportion of the glioma, another pattern including complicated vascular protrusion and spiral running, is seen.

Brain Neoplasms↗
PubMed1988

Primary pulmonary hypertension in pregnancy.

Primary pulmonary hypertension (PPH) is an uncommon but serious disease. Most patients with PPH are young women and the disease is more serious and eventful in pregnant women. We have experienced a patient with PPH in pregnancy, who was delivered successfully but died suddenly on the 7th day after the delivery. We report the obstetric course and the clinical management for the delivery of the patient with PPH.

Adult↗
PubMed1988

Lymphadenectomy for cure in patients with early gastric cancer and lymph node metastasis.

The anatomic distribution, size, and histologic mode of involvement of 98 metastatic lymph nodes in 49 of 370 patients were examined to determine to what extent lymphadenectomy should be performed in addition to gastrectomy in patients with early gastric cancer. Nodal involvement in the marginal sinus (30 nodes) and partial medullary sinus (37 nodes) were commonly seen, and the lymph nodes of those types were enlarged compared with 1,086 patients with no metastatic lymph nodes (control group). Lymph nodes of the wide medullary sinus (11 nodes), small nodule (3 nodes), and massive involvement types (17 nodes) did not enlarge compared with those of the other types and those of the control group. Most of the metastatic sites (76.6 percent) were in the perigastric lymph nodes along the lesser and greater curvatures, about a fifth were in the extraperigastric nodes along the left gastric, common hepatic, celiac, and splenic arteries, and the least were in the extraperigastric nodes (3.1 percent) along the hepatoduodenal ligament. Since the rate of macroscopic diagnosis during operation was so poor, regardless of the histologic modes of nodal involvement, and also in cases of metastatic lymph nodes less than 15 mm in widest diameter, for curative operation of patients with early gastric cancer, perigastric and extraperigastric lymph nodes along the main arteries near the stomach should be completely dissected, in addition to resection of the stomach.

Adenocarcinoma↗
PubMed1988

Primary choriocarcinoma of the urinary bladder.

A case of choriocarcinoma of the urinary bladder is presented. A 57-year-old man underwent a cystectomy for transitional cell carcinoma, grade II. Choriocarcinoma was found, in addition to the transitional cell carcinoma, in the removed urinary bladder. After the operation, metastases appeared in both lungs, evolving rapidly despite chemotherapy. The patient died five months after admission. Immunohistochemically, staining for human placental lactogen was strongly positive, and both alpha and beta subunits of human chorionic gonadotropin were weakly positive in the primary site of the removed urinary bladder and in the metastatic foci.

Carcinoma, Transitional Cell↗
PubMed1988

Mechanism underlying relaxations caused by prostaglandins and thromboxane A2 analog in isolated dog arteries.

In helical strips of dog cerebral, coronary, mesenteric, and renal arteries treated with ONO3708, an inhibitor of vasoconstricting prostaglandin (PG) receptors, and previously contracted with serotonin, PGF2 alpha, PGD2 and epithio-methano thromboxane A2 (sTxA2), a TxA2 analog, caused a relaxation. The cerebral arterial relaxation was suppressed by treatment with indomethacin and abolished by diphloretin phosphate (DPP), a PG antagonist. On the other hand, the relaxation of mesenteric arteries was not influenced by indomethacin but was markedly attenuated by DPP. Removal of endothelium did not alter the relaxation. Relaxations of coronary and renal arteries by PGF2 alpha were suppressed by indomethacin and DPP, whereas the PGD2-induced relaxation was not affected by indomethacin but was abolished by DPP. Concentration--relaxation curves for PGI2 were shifted to the right by treatment with DPP. It is concluded that after ablation of the constrictor response, dog cerebral arteries relax in response to PGs and TxA2, probably due mainly to the release of PGI2-like substance from the arterial wall and to the action of PGI2 receptive sites, whereas the mesenteric arterial relaxation appears to be associated with their action on PGI2 receptors in smooth muscle cells. PGF2 alpha-induced relaxations in coronary and renal arteries may result from the release of PGI2, and relaxations by PGD2 from the action on PGI2 receptors.

Animals↗
PubMed1988

Demonstration of three distinct immunological disorders on erythropoiesis in a patient with pure red cell aplasia and autoimmune haemolytic anaemia associated with thymoma.

A patient with pure red cell aplasia (PRCA) and autoimmune haemolytic anaemia (AIHA), associated with a thymoma which had already been removed, was studied in order to investigate the pathogenesis of PRCA and AIHA. The autoantibody eluted from the surface of the patient's red blood cells (RBC) reacted with the large E antigen of the Rh complex. Immunoglobulin-G (IgG) purified from the patient's serum suppressed CFU-E and BFU-E but not CFU-GM colony formation in the presence of complement. This antibody was not adsorbed with large E antigen. T-lymphocytes in the bone marrow suppressing autologous CFU-E and BFU-E colonies were demonstrated. Thus, three distinct immunological disorders on erythropoiesis were present in this patient with PRCA and AIHA associated with thymoma in a thymectomized state.

Anemia, Hemolytic, Autoimmune↗
PubMed1988

Neuroeffector actions of thromboxane B2 in dog isolated mesenteric arteries.

1. Thromboxane (TX) B2 and epithiomethano (sTXA2), in concentrations that were insufficient to alter the basal tone, potentiated contractile responses of helical strips of dog mesenteric arteries to transmural electrical stimulation. The potentiating effect of TXB2 (up to 10(-6) M) was not abolished by diphloretin phosphate (DPP), a prostaglandin antagonist, whereas the potentiation by sTXA2 was abolished by the antagonist. 2. sTXA2 and TXB2 (3 x 10(-6) M or higher) potentiated the responses to noradrenaline, the potentiation being antagonized by DPP. 3. 3H-overflow evoked by transmural stimulation in superfused arterial strips previously soaked in medium containing [3H]-noradrenaline was increased by TXB2, but not altered by sTXA2. 4. TXB2 in low concentrations potentiated the contractile response to adrenergic nerve stimulation, possibly by increasing the release of noradrenaline, while the potentiation by the TXA2 analogue appears to be due to increased sensitivity of the arteries to noradrenaline. Prejunctional effects of TXB2 may be mediated by receptor sites functionally different from those located postjunctionally.

Animals↗
PubMed1988

Prostaglandins involved in contractions by angiotensin II and bradykinin of isolated dog sphincter pupillae.

1. The dog isolated sphincter pupillae contracted in response to acetylcholine, angiotensin II (AII), bradykinin, prostaglandins F2 alpha, D2, E2 and I2, and thionate thromboxane A2 (sTXA2) in a concentration-dependent manner. 2. AII-induced contractions were suppressed by treatment with saralasin, indomethacin, aspirin and diphloretin phosphate (DPP), a prostaglandin receptor antagonist. Contractions induced by bradykinin were also attenuated by indomethacin, aspirin and DPP. The amount of prostaglandin F2 alpha (PGF2 alpha) in the bathing media was increased approximately 41% following stimulation of the preparations by bradykinin. 3. The potency of contractile responses was in the order of PGF2 alpha greater than PGD2 = sTXA2 greater than PGE2 greater than arachidonic acid greater than PGI2. Contractions induced by PGF2 alpha were not significantly affected by treatment with indomethacin and ONO3708, an antagonist of the vasoconstrictor effect of prostaglandins, but appreciably attenuated by DPP. Arachidonic acid-induced contractions were inhibited by indomethacin. 4. Contractions of dog iris sphincter muscle in response to AII and bradykinin may be mediated via substances synthesized by cyclo-oxygenase from arachidonic acid. The distribution and nature of the prostaglandin receptors appear to differ markedly in iris sphincter and vascular smooth muscles.

Angiotensin II↗
PubMed1988

Diagnosis and surgical treatment of spasmodic torticollis of 11th nerve origin.

Of 22 patients with spasmodic torticollis, 7 were treated by microsurgical decompression of the 11th nerve. In these patients, there was an intermittent horizontal torticollis characterized by aggravation of the symptoms when in a resting posture, presenting with a striking contrast to the torticollis of extrapyramidal origin that was alleviated while in the resting posture and aggravated by postural stress. A tight neurovascular contact was observed at the C1 level, occurring between the principal 11th nerve and the vertebral or posterior inferior cerebellar artery. Nerve decompression was achieved in 2 by transposing the compressing artery and in 5 by sectioning at C1 or C2 the branching root of the 11th nerve that had caused the tight cross contact by locking the nerve trunk to the dura mater. The symptoms had improved after an interval of 1 to 4 weeks. After an average follow-up of 3 years, full or satisfactory relief had been obtained in 5 and some improvement had occurred in 2 patients. Possible neural mechanisms related to torticollis of 11th nerve origin are discussed.

Accessory Nerve↗