Search PubMed⌕ Search

Biomedical subjects

M Hashimoto

Publications and source records attributed to M Hashimoto.

At least 901 records · Page 50Linked to original sources
PubMed1989

Antihypertensive mechanism of alacepril. Effects of its metabolites on the peripheral sympathetic nervous system.

To elucidate the antihypertensive mechanisms of alacepril (DU-1219), the drug itself and its metabolites, desacetylalacepril (DU-1227) and captopril, were examined both in vitro and in vivo for their effects on the sympathetic nerve which innervates the peripheral vessels. 1. In isolated perfused mesenteric preparations from spontaneously hypertensive rats (SHR, DU-1227 (10(-6)-10(-5) mol/l) attenuated dose-dependently the increases in perfusion pressure and in norepinephrine (NE) overflow which were induced by electrical stimulation of periarterial sympathetic nerves (15 Hz). Captopril (10(-6)-10(-5) mol/l) caused a similar attenuation, though to a lesser degree, of the perfusion pressure but did not inhibit the increase in NE overflow. 2. The sympatho-inhibitory effect of DU-1227 in the above experiment was shown to be caused by DU-1227 per se, since no captopril was detected in either the perfusate or tissues perfused with DU-1227. 3. In pithed SHR, alacepril (3 mg/kg) caused as potent an inhibitory effect as captopril (3 mg/kg) on the pressor response to the electrical sympathetic nerve stimulation (3 Hz) at an oral dose about half as that of captopril on the molar basis. The effect of alacepril tended to last longer than that of captopril. However, at higher oral dose levels, the inhibitory effect of alacepril (30 mg/kg) was of the similar extent to that of captopril (30 mg/kg). 4. In pithed SHR which had received bilateral nephrectomy 2 to 8 h previously, alacepril (30 mg/kg p.o.) significantly attenuated the vasopressor response induced by electrical stimulation (1-30 Hz) 1 and 3 h after administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1989

[A case of benign fibrous histiocytoma of the lung in a child].

A case of benign fibrous histiocytoma of the lung in a 8 years old boy was presented. He was first admitted in May, 1983, with recurrent pneumonia. Chest X-ray showed a ill-defined mass in the right lower lobe. Bronchoscopy revealed a round tumor, 1 cm. in maximum diameter, with complete obstruction of the Truncus Intermedius. Endoscopic resection was performed and partial obstruction of the Truncus Intermedius remained. He was re-admitted with pneumonia of the right middle lobe in March, 1986. Bronchoscopy showed severe stenosis of the Truncus Intermedius. Right middle and lower lobectomy was performed. The 4 X 4 X 3 cm tumor was located in the median of the Truncus Intermedius. Microscopically, the lesion composed of fibroblast-like cells and histiocyte-like cells. The patient's post-operative course was uneventful. He has no signs of local recurrence or metastasis. We believe, this is the first reported primary benign fibrous histiocytoma of the lung in a child in Japan.

Bronchial Neoplasms↗
PubMed1989

[Impaired superoxide production by neutrophils in myelodysplastic syndrome: correlation with bone marrow karyotype].

Superoxide (O2-) production by neutrophils was examined in 21 patients with myelodysplastic syndrome (MDS), including 13 with primary MDS (p-MDS) and 8 with therapy-related MDS (t-MDS). O2-production of MDS patients was significantly less than that of healthy controls (2.81 +/- 3.51 vs 6.19 +/- 2.41 nmol/min/10(6) PNMs, p less than 0.005). Although no relationship between pathogenesis (primary or therapy related), FAB type and levels of O2- production was observed, O2- production of 11 patients with abnormal bone marrow karyotypes was significantly reduced than that of 10 other patients with normal karyotypes. Furthermore, five t-MDS patients with monosomy for all or part of chromosome no. 7 (-7 or 7q-) showed the lowest level of O2- production, which was significantly different from the level in the patients with other abnormal karyotypes (0.61 +/- 0.29 vs 1.80 +/- 0.31, p less than 0.001). These results suggest that the long arm of chromosome no. 7 may in part play an important role for O2- production by neutrophils.

Adult↗
PubMed1989

[Angiographic features of malignant fibrous histiocytomas].

The angiographic findings in eight cases with malignant fibrous histiocytomas are described. These lesions were well demarcated and demonstrated fine tumor vessels, homogenous stains with avascular areas presenting central necrosis. But these angiographic findings could not differentiate MFH from synovial sarcoma and fibrosarcoma.

Adult↗
PubMed1989

[Syrinx-like artifact on MR images of the spinal cord].

We evaluated the syrinx like artifact on midline sagittal MR images of cervical spine. This artifact appeared as linear regions of low intensity along the length of the spinal cord. This artifact was frequently seen. And, when it appear as a single midline band, it mimics pathological conditions such as a syrinx. We found that this artifact eliminated by increasing the number of phase encoding steps, or decreasing the field of view. These method were useful for differentiation of artifact from syrinx.

Cervical Vertebrae↗
PubMed1989

Immunohistological identification of T and B cells in normal and malignant tissues of the uterine endometrium.

We examined the state of T and B cells in tissues from 61 cases of endometrial cancer by immunohistochemistry with monoclonal antibodies. In cancer tissues, T cells frequently appear in clusters at the tip of the infiltrating cancer. As to age, both T and B cells were rare in 9 out of 11 cases involving endometrial cancer in patients in their 40s. In the normal endometrium, infiltration of numerous T cells was seen in only 2 out of 27 cases (7.4%). However, it was seen in cancer tissues in 28 out of 61 cases (45.9%). Thus the infiltration of numerous T cells into cancer tissues was confirmed. Within the same uterus, T cells seldom infiltrated into the area of the benign endometrium while T cells were seen in large numbers in the cancer foci. This indicates that T cells infiltrate after having recognized cancer cells. Compared to stages I and II, T cell infiltration tended to decrease in stages III and IV. While no fixed relation was found between the degree of histologic differentiation and T cell infiltration, fewer T cells were observed in the cases where cancer penetrated to the depth of cancer invasion and where it occupied a large area. Thus, it was assumed that in the host-immune defence mechanism in particular, T cell infiltration played a key role in tumor immunology of patients with endometrial cancer.

Adult↗
PubMed1989

Granuloma formation by artificial microparticles in vitro. Macrophages and monokines play a critical role in granuloma formation.

To investigate the basic mechanisms of granuloma formation, in vitro granulomas were induced by culturing murine spleen cells in the presence of artificial microparticles. Large granulomas developed around dextran beads. The lesions were inducible by spleen cells from either normal mice or athymic nude mice. Minimal inflammation was produced around latex beads. The histologic features and time kinetics of granulomas in vitro. Culture supernatants of dextran induced granulomas contained high levels of interleukin-1 (IL-1) activity but not interleukin-2 (IL-2) or interleukin-4 (IL-4) activity. IL-1 activity was correlated with granuloma size. Additionally, granulomas were produced by culturing spleen cells in the presence of agarose beads coupled to recombinant IL-1 or recombinant tumor necrosis factor-alpha (TNF-alpha). Granulomatous lesions also were induced by macrophage-enriched populations in the presence of monokine-coupled beads. Adherent macrophages, but not nonadherent cells, were required for induction of granulomas in vitro. In contrast, very small lesions were seen when spleen cells or adherent cells were cultured in the presence of beads coupled to recombinant IL-2 or recombinant interferon-gamma (IFN-gamma). These results suggest that macrophages and monokines such as IL-1 and TNF-alpha play an essential role in granuloma formation in vitro.

Animals↗
PubMed1989

[A case of mediastinal schwannoma originating from the intrathoracic vagal nerve].

A 46-years-old man was admitted because of an abnormal shadow on X-ray. The operation underwent under the diagnosis of benign tumor in the antero-superior mediastinum. At the operation, the tumor arise from the right intrathoracic vagal nerve and it was resected with the transection of vagal nerve. The histological diagnosis was schwannoma. Postoperative course was uneventful except the slight hoarseness. Intrathoracic vagal tumor is rare and we have found 19 reported cases among Japanese literatures. This case is considered to be the 20th case originated from the intrathoracic vagal nerve in Japan.

Cranial Nerve Neoplasms↗
PubMed1989

[Analysis of ocular circulatory kinetics in glaucoma by the ultrasonic Doppler method].

In order to analyze ocular circulatory kinetics in relation to the stages of progression of primary open-angle glaucoma, the pulse wave of flow velocity in the central retinal artery was measured by the ultrasonic Doppler method. In eyes with glaucoma, the ratio of blood flow velocity of the central retinal artery (fundus artery: FA) to that of the ophthalmic artery (medial frontal artery: OA) was smaller and, at the same time, the pulse rise time (PRT) of the pulse wave of flow velocity was shorter than in normal eyes, a tendency which increased as the disease progressed. The ratio of FA to OA in terms of velocity [V (FA/OA)] showed a significant inverse correlation with the degree of visual field disorder (Kosaki classification) and the ratio in terms of PRT [T (FA/OA)] showed significant inverse correlation with the C/D ratio of the papilla. An ultrasonic Doppler blood flowmeter with 2 frequencies, attached to an integral spectrum analyzer for indicating the direction of blood flow using real time sonography (Vasoflo-3), was used. The investigation was conducted on 100 eyes with primary open-angle glaucoma in 60 patients aged 20-70 years [28 males and 32 females (mean age 64.3 +/- 12.1)], and 60 eyes in 30 normal subjects of the same age (mean age 58.1 +/- 14.3). These results demonstrated that the ultrasonic Doppler method is useful for the observation of ocular circulatory kinetics in eyes with glaucoma.

Adult↗
PubMed1989

A transient hemolytic reaction and stomatocytosis following vinca alkaloid administration.

We analyzed hemolytic reaction following vinca alkaloid administration in patients with acute lymphoblastic leukemia, blast crisis of chronic myelogenous leukemia and malignant lymphoma in the leukemic phase. During the course of chemotherapy in which vinca alkaloids were included, indirect-form dominant hyperbilirubinemia was observed in 21 of the 31 evaluable patients. In 8 patients with hyperbilirubinemia, reticulocytosis coincided with vinca alkaloid administration. Peripheral blood films showed prominent anisocytosis in 4 patients and increased stomatocytes in 10 patients. Red cell membrane studies in patients with hemolysis revealed increased sodium transport and increased activity of Na+, K+-ATPase. These findings were considered to represent the abnormal membrane "leakiness". Thus, vinca alkaloids might induce erythrocytotoxicity, which leads to acquired stomatocytosis with hemolysis in some patients.

Adult↗
PubMed1989

[Acute leukemia complicated by hyperbilirubinemia due to high dose cytosine arabinoside therapy].

A 58-year-old man was admitted to our hospital because of low grade fever and purpura in September. 1987. On admission, his bone marrow aspiration showed nucleated cell count of 48 x 10(4)/mm3 with 94.6% of promyelocyte-like leukemic cells. A diagnosis of acute promyelocytic leukemia was made and he was treated with high dose cytosine arabinoside (HDAra C). After this therapy, serum bilirubin, especially direct bilirubin was increased and hyperbilirubinemia was progressed with normal transaminase levels. He had complicated by pneumonia and died of respiratory failure. Autopsy revealed only cholestasis in the liver with neither hepatic cell necrosis nor cell infiltration. This case was though to be a rare case with cholestatic liver injury due to HDAra C.

Cholestasis, Intrahepatic↗
PubMed1989

[A case of eosinophylic lymphoid granuloma (Kimura's disease) being suspected as cervical tuberculosis].

Although cervical tuberculous lymphadenitis has decreased markedly in accordance with the decline of pulmonary tuberculosis in Japan, a few cases are still found among young people. A thirty-year-old man, being suspected as cervical tuberculous lymphadenitis, underwent a biopsy, and was histologically diagnosed as eosinophilic lymphoid granuloma (Kimura's disease). He had many indurated nodules in the cervical and lower jaw regions (fig. 1). The clinical and biochemical findings were normal except leucocytosis (11,000/mm3) and eosinophilia (19%) in peripheral blood. The histological section showed nodular lesions, composed of collective lymphoid cells with new formation of germinal centers and capillary vessels. Diffuse infiltration of histiocytes, eosinophils and lymphocytes was found through out the lesions. Following daily Predonine medication with decreasing dose from 30 mg to 2.5 mg in one and a half months, the consolidation in the cervical and lower jaw regions became smaller and finally disappeared.

Adult↗
PubMed1989

Interaction of enoxacin with theophylline in rats.

Enoxacin (ENX) has been reported to raise significantly plasma levels of theophylline (TP) in humans. In order to elucidate a mechanism of this interaction, in vivo and in vitro studies were carried out in rats. Concomitant dosing of ENX with TP significantly elongated plasma elimination half-life of TP, which led to a marked increase in the maximum plasma TP level after repeated administrations of both drugs. In rats treated with ENX, urinary excretion of unchanged TP increased and that of TP metabolites comparably decreased. The pharmacokinetic analysis showed that ENX did not change renal clearance of TP and these observed effects of ENX were attributed to reduced metabolic clearance of TP. In the in vitro studies by using liver microsomes, ENX reduced the magnitude of the type II difference spectral interaction of TP with cytochrome P-448 (P-448) and the formation of TP metabolites catalyzed by P-448. These results strongly suggest that the inhibition of the TP binding to the ferric iron of P-448 leads to that of the TP metabolism. The most essential site of ENX to inhibit the TP metabolism was found to be the 4'-nitrogen atom in the 7-piperazinyl group, and the stereochemical structure of ENX was suggested to be responsible for this inhibition.

Animals↗
PubMed1989

[Antibiotics-induced agranulocytosis. Patient's IgG inhibits a GM colony formation].

The pathogenesis of Cefmetazole (CMZ) induced agranulocytosis was investigated in the case of a 40-year-old man who developed agranulocytosis while he was under treatment with CMZ. Although concentration of CMZ in serum is not detected, patient's serum drawn at the time of diagnosis suppressed normal allogeneic marrow GM colonies in vitro. Normal IgG purified from serum had no effect on GM colony formation in vitro. However, patient's IgG purified from serum drawn at the time of diagnosis suppressed normal allogeneic marrow GM colony in vitro without CMZ. These studies suggest that CMZ-induced agranulocytosis is immunologically mediated through an IgG inhibitor which seems to exert its effect on GM colony formation.

Adult↗
PubMed1989

[A case of primary pulmonary cryptococcosis].

A 53-year-old male was admitted because of an abnormal chest roentgenogram showing a solitary tumor shadow in the right upper lung field. Laboratory data was normal. Although examination with the bronchoscope and sputum cytology showed no abnormal findings, a partial resection of the right upper lobe was performed. Microscopic examination of the lesion was cryptococcosis. As another focus was not found by systemic examination, the lesion was disclosed primary pulmonary cryptococcosis. Cryptococcosis is rare but we must think of it when we meet a solitary tumor shadow on the chest roentgenogram.

Cryptococcosis↗