Biomedical subjects

M Hashimoto

Publications and source records attributed to M Hashimoto.

At least 721 records · Page 40Linked to original sources

PubMed1992

Lymphangioma in the small intestine: report of a case and review of the Japanese literature.

We report herein a rare case of a 53 year old man with a benign lymphangioma of the small intestine. He presented with a complete obstruction of the small intestine and radiological examination revealed a small intestinal tumor. A long intestinal tube was passed, the intestinograms from which detected a submucosal tumor of the small intestine. Partial resection of the small intestine was thus performed and the tumor was found to be located mainly in the submucosa. The final pathological diagnosis was made as cavernous lymphangioma. This case is presented with a description of the roentgen appearance, followed by a review of the Japanese literature.

Adult↗

PubMed1992

Hemodynamic changes after resection of thoracic duct for en bloc resection of esophageal cancer.

An en bloc resection of esophageal cancer is one of the most radical forms of esophagectomy, and includes the resection of the thoracic duct, but a relatively high hospital mortality rate has been reported. There is very little knowledge on the pathophysiological changes after resection of the thoracic duct. We examined 24 patients who underwent en bloc resection. Some patients developed severe tachycardia or shock postoperatively which subsided after a massive infusion of plasma. Analysis of the fluid balance revealed that much more fluid was necessary during surgery and the postoperative 24 h than in patients treated by a standard esophagectomy. Postoperative lymphangiography or CT revealed abnormal collateral lymphatics around the kidneys or in the pelvic cavity. This suggests the development of the lymphaticovenous shunts, which differed depending on the anatomy of each patient. One patient with chronic hepatitis developed uncontrollable ascites. These are important findings which can hopefully reduce the high rate of hospital death after this operation.

Aged↗

PubMed1992

Suppression of pulmonary granulomatous inflammation by immunomodulating agents.

We demonstrated previously that macrophages and macrophage-derived cytokines including lymphocyte-activating factors (LAFs) play a critical role in lung granuloma formation in mice and that granulomas sizes correlated with LAF activity in the lesions. In the present study, we examined the effects of D-penicillamine (D-Pc), 2-acetylthiomethyl-3-(4-methyl-benzoyl)propionic acid (KE-298) and dexamethasone (Dex) on dextran bead-induced lung granulomas in mice. KE-298 is a newly synthesized compound containing sulfur (S) similar to D-Pc. Large granulomas developed, which reached peak intensity within 3 days and declined in size thereafter. Aqueous lung extracts of the mice contained high levels of LAF that were correlated with granuloma sizes. The lesions and local LAF activity were inhibited by administration of these agents. The most potent inhibitor was Dex. The suppressive effect of KE-298 was similar to that of D-Pc. These results suggest that suppression of granulomas may be attributed to inhibition of LAF activity/synthesis by these agents.

Animals↗

PubMed1992

A case of combined primary biliary cirrhosis, ulcerative colitis and chronic myelocytic leukemia.

A rare case of primary biliary cirrhosis, ulcerative colitis and chronic myelocytic leukemia is described in a 49-year-old Japanese diabetic woman. Primary biliary cirrhosis was diagnosed by characteristic liver histology and positive serum mitochondrial antibody test. Ulcerative colitis was diagnosed by typical findings of barium enema and colonoscopy, negative fecal test for pathogens and compatible rectal histology. Chronic myelocytic leukemia was determined by representative hematologic findings and positive result for Ph1 chromosome. This is the first case with combination of primary biliary cirrhosis, ulcerative colitis and chronic myelocytic leukemia.

Colitis, Ulcerative↗

PubMed1992

Overexpression of plant histidinol dehydrogenase using a baculovirus expression vector system.

A cDNA encoding cabbage histidinol dehydrogenase, including the chloroplast transit peptide sequence, was overexpressed using a baculovirus expression vector system. The maximum level of the expression of histidinol dehydrogenase was reached 5 days after infection of the insect cells. Two forms of recombinant histidinol dehydrogenase with molecular masses of 53 and 52 kDa, respectively, were obtained by a one-step purification from the cell homogenate. Compared with the 52-kDa form, the 53-kDa form contained 10 additional amino acids at the N-terminus derived from the transit peptide. By incubating the cell homogenate for 2 h at 30 degrees C, the 53-kDa form could be completely converted to the 52-kDa form. This conversion was blocked by leupeptin. Eighty percent of the converted 52-kDa form had Cys at position 31 at the N-terminal amino acid and the rest had Met 33. Kinetic properties of the recombinant enzyme were virtually identical to those of histidinol dehydrogenase isolated from cabbage plants. The overexpression of recombinant cabbage histidinol dehydrogenase in insect cells, the proteolytic processing of the preprotein next to the N-terminus (compared to the mature cabbage enzyme), and its easy purification allow the preparation of large amounts of the active enzyme for structural and functional studies.

Alcohol Oxidoreductases↗

PubMed1992

Clinical evaluation of the gingiva around single-crystal sapphire endosseous implant after experimental ligature-induced plaque accumulation in monkeys.

This study was performed to evaluate clinical changes of the gingiva with plaque accumulation around the single-crystal sapphire implant. Four implants were inserted into mandibular and maxillary edentulous regions, and the superstructure was inserted 1 month after insertion of the implants in each of nine monkeys. Plaque control was maintained for 3 months after insertion to set up the baseline. Plaque was allowed to accumulate on one side by placing the ligature around the implant and natural teeth without any plaque control, and on the other side plaque control was continued for 9 months. Both the implant and natural teeth on the ligature side showed a significant increase in the clinical parameters of plaque index, gingival index, and probing depth. No significant difference was obtained between the implant and natural teeth. These findings indicate that plaque control is of great importance for maintaining the health of peri-implant gingiva.

Aluminum Oxide↗

PubMed1992

Medulla oblongata germinoma in association with Klinefelter syndrome.

A rare case of medulla oblongata germinoma in a 19-year-old Japanese man with Klinefelter syndrome is presented. Light microscopic examination of the resected specimen showed very few lymphocytes, and an immunohistochemical study for placental alkaline phosphatase was of great diagnostic value. Up to now there have been only five cases of intracranial germ cell tumors in association with Klinefelter syndrome. These tumors were situated along in the midline structure. It is emphasized that endocrinological factors at the time of embryogenesis as well as a genetic malignant potential are important in the pathogenesis of extragonadal germ cell tumors associated with Klinefelter syndrome.

Adult↗

PubMed1992

Specific and abundant secretion of a novel hydroxyproline-rich glycoprotein from salt-adapted winged bean cells.

Winged bean callus was adapted to increasing concentrations of NaCl by sequential transfer to medium with 0, 0.5, 1.0, 1.5, and 2.0% (w/v) NaCl. When the culture media, after cell suspension cultures of callus adapted to 0.5 (SA-0.5), 1.0 (SA-1.0), 1.5 (SA-1.5), or 2.0% (w/v) NaCl (SA-2.0), were analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis, six specific or enhanced polypeptide bands (SAP1, -2, -3, -4, -5, and -6) were observed. SAP1, with a molecular weight of 84,000, was abundantly secreted in suspension cultures of SA-1.0 and SA-1.5, and was observed as the most striking polypeptide band. The SAP1 yield was about 4 mg/g cells fresh weight. SAP1 was abundantly secreted after the suspension culture of SA-1.0 in the presence of AlCl(3), but little was secreted in the presence of KCl, LiCl, CaCl(2), MgCl(2), mannitol, sucrose, or abscisic acid. SAP1 was purified from the culture medium after suspension culture of SA-1.0 in the presence of 1.0% (w/v) NaCl. Two steps, ammonium sulfate fractionation and CM-cellulose chromatography, were sufficient for purification to homogeneity. Finally, about 5 mg of SAP1 could be isolated from 7 g of fresh callus cells. Of the amino-terminal 32 amino acid residues of SAP1, 10 and 5 were found to be hydroxyproline and proline, respectively. SAP1 on an acrylamide gel was stained by the periodic acid-Schiff method. It is interesting that SAP1 has pentahydroxyproline blocks (Hyp(5)) instead of tetrahydroxyproline blocks (Hyp(4)) common to many hydroxyproline-rich glycoproteins in dicotyledons. Thus, this novel hydroxyproline-rich glycoprotein was shown to be abundantly secreted from NaCl-adapted winged bean cells.

Journal Article↗

PubMed1992

Spinal arachnoid cyst in a newborn infant.

A male infant was born with asphyxia following a prolonged breech delivery at 39 weeks of gestation. He had a chylohemothorax from birth. Soon after birth he exhibited flaccid paraplegia with an absence of deep tendon reflexes in the lower extremities. At 17 days of age, magnetic resonance imaging (MRI) disclosed a hypodense area in the thoracic cord between C7 and Th4 in T1-weighted images, and spinal sonography revealed an echo-free space compressing the spinal cord in the same region observed with MRI. A spinal cyst was removed surgically at 24 days of age. The cyst was confirmed by pathology to be a true arachnoid cyst between C7 and Th4. The cause of this cyst may have been a spinal cord injury during the perinatal period.

Arachnoid Cysts↗

PubMed1992

Responses of isolated Japanese monkey tracheal muscle to allergic mediators.

The responsiveness of isolated Japanese monkey (Macaca fuscata) tracheal muscle to antigen, carbachol, histamine, leukotriene C4 (LTC4), U-46619 and substance P (SP) was compared to that of isolated human trachea. Weak but persistent contraction was observed after the addition of antigen to isolated Japanese monkey tracheal muscle passively sensitized with monkey serum containing IgE antibody against Japanese cedar (Cryptomeria japonica) antigen. Unlike monkey tracheal muscle, a fair amount of contraction was caused by the antigen in human tracheal muscle passively sensitized with human atopic serum. When chopped, passively sensitized monkey or human lung tissue was challenged with antigen, a significant level of histamine was released from these tissues. In Japanese monkey tracheal muscle, histamine and SP produced no contraction of tracheal muscle, whereas carbachol, LTC4 and U-46619 caused contraction in a dose-dependent fashion. Contrary to the Japanese monkey, histamine and carbachol caused distinct contraction in tracheal muscle obtained from the cotton-headed tamarin (Saguinus oedipus). In human tracheal muscle, all test substances (carbachol, histamine, LTC4, U-46619 and SP) induced clear contraction. In lung parenchyma obtained from Japanese monkey, histamine induced a weak contraction, and this histamine-induced contraction was also inhibited by pyrilamine (H1 receptor antagonist). These results indicate that antigen-induced contraction of isolated Japanese monkey tracheal muscle, passively sensitized with monkey atopic serum, is not a useful model for human allergic bronchoconstriction in vitro because of the unresponsiveness of tracheal muscle to histamine and SP.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

PubMed1992

Assessment of endothelium-derived relaxing factor from human coronary arteries using the anti-platelet aggregatory effect.

Responses of human and canine washed platelets to thrombin in the presence and absence of human and canine coronary arteries were examined to establish a simple indirect measurement system for endothelium-derived relaxing factor (EDRF). Isolated rings of coronary arteries were obtained from either adult dogs or recipient hearts of cardiac transplant patients. The addition of small segments of canine and human coronary arteries with intact endothelia inhibited thrombin-induced platelet aggregation, but those with disrupted endothelia did not. Pretreatment of human and canine coronary arteries with the cyclo-oxygenase inhibitor indomethacin markedly attenuated the observed effect. The anti-platelet aggregatory effect of indomethacin-pretreated coronary artery was enhanced by acetylcholine or histamine, stimulators of EDRF production, or superoxide dismutase, which prolongs the half-life of EDRF, and inhibited by the EDRF inhibitor hemoglobin. These results suggest that endothelial cells of the human coronary artery, like the canine coronary artery, can produce EDRF which inhibits platelet aggregation, and that this simple experimental model is useful to examine the effect of environmental chemicals on EDRF in the human coronary artery.

Animals↗

PubMed1992

Injury to cultured human vascular endothelial cells by copper (CuSO4).

The effect of copper sulfate (CuSO4) on cultured human vascular endothelial (HVE) cells and cultured human fibroblasts (HAIN-55) was investigated. HVE cells were collected from umbilical veins by enzymatic digestion with collagenase. The viability, subsequent growth and DNA synthesis of both cell types were inhibited concentration-dependently by the addition of copper. The cytotoxic effect of copper on the morphology of these cells was also concentration-dependent. However, the cytotoxic effect of copper on the viability, subsequent growth and DNA synthesis was greater in HVE cells than in HAIN-55 cells. These results suggest that HVE cells are more susceptible to concentration-dependent copper cytotoxicity than HAIN-55 cells are, and that copper could induce vascular endothelial injury, which may be involved in the pathogenesis of cardiovascular disease.

Cardiovascular Diseases↗

PubMed1992

Prostaglandin F2 alpha- and phorbol 12-myristate-13-acetate-stimulated progesterone production by cultured human luteal cells in the mid-luteal phase: prostaglandin F2 alpha increases cytosolic Ca2+ and inositol phosphates.

While prostaglandin F2 alpha (PGF2 alpha) has been thought to be a natural luteolysin in non-primates, a luteolytic effect in the human corpus luteum is less evident. We therefore investigated the action of PGF2 alpha on monolayer cultures of human luteal cells obtained from mid-luteal phase corpora lutea. PGF2 alpha increased basal and human chorionic gonadotrophin (hCG)-stimulated progesterone production by human cultured luteal cells. A potent tumour-promoting phorbol ester, phorbol 12-myristate-13-acetate (PMA), also stimulated progesterone production by cultured human luteal cells. Although human luteal cells were incubated for 24 h with PMA, hCG was still able to stimulate the production of progesterone by PMA-pretreated cells. However, PMA pretreatment blocked the ability of PGF2 alpha to stimulate progesterone production. It is possible that the luteotrophic effect of PGF2 alpha may be mediated, in part, by the activation of protein kinase C. Addition of PGF2 alpha to suspensions of human luteal cells preincubated with myo-[2-3H]inositol promoted an increase in labelled inositol phosphates. PGF2 alpha also rapidly increased intracellular free Ca2+ in human luteal cells loaded with the fluorescent Ca2+ probe, fura-2. We conclude that PGF2 alpha and PMA stimulate progesterone production and that PGF2 alpha increases the intracellular free calcium and inositol phosphates of human cultured luteal cells in the mid-luteal phase.

Calcium↗

PubMed1992

Renal artery aneurysm: the significance of abdominal bruit and use of color Doppler.

A case of renal artery aneurysm is presented. The patient had no hypertension and no signs of arteriosclerosis obliterans or aortitis syndrome, except for abdominal bruit. A saccular aneurysm, 1 cm in diameter, was demonstrated by two-dimensional and color Doppler ultrasound and documented by angiography. The aneurysm was embolized by a steel coil. The abdominal bruit, though uncommon, is a very important bed-side sign of renal artery aneurysm, if the patient exhibits no arteriosclerosis obliterans or aortitis syndrome. Ultrasound Doppler is very useful in screening for aneurysm.

Aneurysm↗

PubMed1992

Hemodynamic changes due to afterload reduction as a predictor of exercise capacity in patients with dilated cardiomyopathy.

Sixteen patients with dilated cardiomyopathy were examined hemodynamically in order to clarify the relationship between the exercise capacity and the effects of afterload reduction at rest using supine graded bicycle exercise testing before and after sublingual administration of 10 mg nifedipine. 1) The integration of work loads was weakly correlated with the stroke index (r = 0.64), heart rate (r = -0.58) and plasma norepinephrine concentration at rest (r = 0.49), but not with the left ventricular ejection fraction, cardiac index, pulmonary arterial diastolic pressure or the mean arterial pressure at rest. 2) Changes in stroke index and heart rate after administration of nifedipine correlated well with the integration of work loads (r = -0.84, r = 0.81, respectively). Thus, in patients with dilated cardiomyopathy changes in stroke volume and heart rate due to afterload reduction at rest were better predictors of exercise capacity than the baseline left ventricular hemodynamic parameters.

Adult↗

PubMed1992

Repeated intracerebral hemorrhage associated with impaired platelet aggregation--report of two cases.

The authors report two cases of hypertensive intracerebral hemorrhage (ICH) repeated at the same site within 1 or 2 days causing death in a 53-year-old male and a 48-year-old female. In both cases, platelet aggregation was significantly impaired. Acquired platelet dysfunction may be important in the expansion of hemorrhage in patients with repeated hypertensive ICH. In such cases administration of normal platelets may be required to prevent devastating hemorrhage.

Blood Platelet Disorders↗

PubMed1992

WS009 A and B, new endothelin receptor antagonists isolated from Streptomyces sp. no. 89009. II. Biological characterization and pharmacological characterization of WS009 A and B.

WS009 A and B, produced by Streptomyces sp. No. 89009, were found to be competitive and specific antagonists against endothelin (ET)-1 receptors in in vitro studies and also active in in vivo studies. Furthermore, WS009 A and B were specific antagonists for vascular ET-1 receptors (ETA receptors) and significantly prevented the accumulation of intracellular inositol 1,4,5-triphosphate (IP3) in endothelin treated rat aorta tissues.

Animals↗

PubMed1992

WS9326A, a novel tachykinin antagonist isolated from Streptomyces violaceusniger no. 9326. I. Taxonomy, fermentation, isolation, physico-chemical properties and biological activities.

Data from several studies suggest that tachykinins may play an important role in the pathophysiology of airway diseases, especially asthma. Our aim is to discover tachykinin antagonists which exhibit therapeutically useful anti-asthmatic activity. In our search for activities inhibiting the binding of [3H]substance P to guinea-pig lung membrane preparations, we have found that the fermentation product, WS9326A, isolated from Streptomyces violaceusniger, is a potent tachykinin receptor antagonist.

Animals↗