Biomedical subjects

M Maeda

Publications and source records attributed to M Maeda.

At least 955 records · Page 53Linked to original sources

PubMed1990

[Three operated cases of LMT-lesion with chief complaint of syncopal attack].

An urgent aorto-coronary bypass operation (AC-bypass) was made in three patients with unstable angina pectoris, suffering from stenosis of the left main trunk (LMT). All patients were admitted with chief complaints of chest discomfort and syncopal attack. Case 1 was a 71 year-old man who suffered with chest discomfort and syncopal attack. He was admitted to our emergency room by ambulance 40 minutes after the syncopal attack, on January 11, 1989. His blood pressure was 140/96; pulse 84 and regular. The electrocardiogram (ECG) showed right bundle branch block, ST elevation in aVR, aVL and ST depression in all other leads. Coronary arteriogram (CAG) was made urgently and showed 80% stenosis in LMT. The emergency AC-bypass operation was successfully carried out about 3 hours and 10 minutes after the onset of symptoms. Case 2 was a 51 year-old man who suffered from precordial oppression and syncopal attack. He was admitted to our emergency room by ambulance about 1 hour after the attack, on January 17, 1989. His blood pressure was 94/74; pulse 120 and irregular. Chest radiography showed a cardiothoracic ratio of 58% and the ECG disclosed atrial fibrillation, ST elevation in aVR and ST depression in I, II, III, aVF, V1-6. The echocardiogram revealed hypokinetic motion in the antero-lateral wall of the left ventricle. CAG was carried out without delay, and showed 70% stenosis with slit in LMT. An emergency AC-bypass operation was successfully carried out about 3 hours and 50 minutes after the onset of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1990

[A surgical case of aortic regurgitation with Behçet disease].

A case of Behçet disease associated with aortic valve regurgitation treated with aortic valve replacement is reported. The patient was treated successfully with special surgical techniques for prevention of post operative paravalvular leakage and occurrence of pseudo aneurysm because the patient was under long-term steroid therapy for Behçet disease.

Aortic Valve↗

PubMed1990

[A neuron-specific enolase (NSE) positive leiomyosarcoma].

A 40-year-old woman with multiple skin tumors was admitted to our hospital on September 5, 1989. Extensive studies by means of light and electron-microscopic examination and immunohistochemical analysis revealed a neuron-specific enolase (NSE) positive leiomyosarcoma. The level of her elevated serum NSE decreased after receiving her initial chemotherapy, but after the fourth session of chemotherapy, the NSE began to elevate again and she died on December 25, 1989. NSE appears to be a useful marker for determining if the neuronal and neuroendocrine cells are normal. This rare case, however, seems to demonstrate that abnormal, nonneuronal cells like a sarcoma also open metabolic pathways to synthesize NSE.

Adult↗

PubMed1990

[Effects of lumbar or thoracic epidural anesthesia on median nerve somatosensory evoked potentials].

Somatosensory evoked potentials (SSEP) are used increasingly to monitor the integrity of neural pathways in anesthetized patients. To evaluate the influence of epidural anesthesia on the central nervous system, we studied the effects of lumbar or thoracic epidural anesthesia with lidocaine on the median nerve SSEP in 9 patients. The peak latencies (N1, P2, N2) and amplitudes (N1-P2, P2-N2) of the SSEP response over the sensory cortex were recorded before and 15 min after epidural anesthesia. The peak latencies of control and post epidural anesthesia of N1, P1, N2 were 19.2 +/- 1.7 msec, 19.6 +/- 1.6 msec (N1), 24.7 +/- 2.3 msec, 25.7 +/- 2.0 msec (P2), 32.8 +/- 2.8 msec and 34.6 +/- 2.5 msec (N2), respectively. The amplitude of control and post epidural anesthesia of N1-P2, P2-N2 were 4.5 +/- 2.9 microV, 5.9 +/- 6.6 microV (N1-P2), 4.4 +/- 3.2 microV and 5.6 +/- 5.2 microV (P2-N2), respectively. Peak latencies of all components (L1, P2, N2) increased after epidural anesthesia compared with control values. Amplitude of N1-P2 increased significantly following epidural anesthesia compared with control values. The data obtained in this study were contrary to the previous concept that anesthetic agents generally increase the latency of SSEP and decrease their amplitude.

Adult↗

PubMed1990

[Comparative study between film mammography and xeromammography; including specimen radiography].

We retrospectively evaluated preoperative film- and xeromammography of 23 cases with breast cancers, and compared with postoperative specimen radiography to assess tumor delineation and microcalcification detectability. In tumor detection and margin delineation, film mammography was superior to xeromammography, and in microcalcification, film mammography was equal to xeromammography. These results had a effect on the diagnosis of breast cancers.

Breast Neoplasms↗

PubMed1990

[Acute megakaryoblastic leukemia with complex chromosomal aberrations].

A case of acute megakaryoblastic leukemia with complex chromosomal aberrations is reported. A 63-year-old man was admitted to our hospital because of pancytopenia. Bone marrow aspiration resulted in a dry tap and biopsy showed hypoplastic marrow with fibrosis. Blast cells in the peripheral blood were identified as megakaryoblasts because they were positive for electron microscopic platelet peroxidase (PPO). In addition, monoclonal antibody, TP80, to platelet glycoprotein II b-III a reacted with in about 26% of the blast cells. Chromosomal analysis of the peripheral blood revealed a mosaic pattern of a normal karyotype and abnormal ones, including 44, XY, -5, -7, -18, 10q-, +marker.

Chromosome Aberrations↗

PubMed1990

[B-chronic lymphocytic leukemia/prolymphocytic leukemia (CLL/PL)--a case report].

A 48-year-old male was admitted to our hospital on April 20, 1989 because of general fatigue and abdominal fullness. Physical examination showed hepatomegaly, massive splenomegaly, and systemic lymphadenopathy. Hematological findings revealed WBC 73,000/microliters, RBC 289 x 10(4)/microliters, Hb 8.0g/dl, and platelet 9.1 x 10(4)/microliters. WBC differential count demonstrated a mixture of 63% matured small lymphocytes and 32% prolymphocytoid cells. Bone marrow aspiration was unsuccessful with a dry tap. Surface marker analysis of peripheral blood lymphoid cells disclosed that they were positive for anti-HLA-DR, CD 5, CD 19, CD 20, CD 21, CD 25, Sm-IgM, Sm-IgD, and Sm-K. He was diagnosed as B-CLL/PL, and treated with VEPA with partial remission. CLL/PL which was advocated by Melo in 1986 is regarded as a distinct clinical entity intermediate between CLL and PLL in clinical and laboratory features. Our case is interesting with regard to good response to combination chemotherapy, though most cases of CLL/PL have a resistance to standard chemotherapy.

Antigens, CD↗

PubMed1990

[An aggressive angiomyxoma of the vulva].

A case of an aggressive angiomyxoma of the vulva in a 38-year-old lady is reported. The tumor was gelatinous and 12 x 8 x 7 cm in size. Histologically, spindle or stellate-shaped tumor cells and blood vessels were found distributed in a myxoid stroma. It was found that the tumor cells were immunoreactive to vimentin but negative to desmin and smooth muscle specific actin. Ultrastructurally the tumor cells had an intercellular junction, an abundant, rough endemic reticulum, and intracytoplasmic filaments, but no focal densities of the filaments and the basal lamina. These findings have revealed that this tumor consisted of myofibroblastic cells resembling fibroblasts rather than myofibroblasts.

Adult↗

PubMed1990

[Evaluation of MRI for the staging of esophageal cancer].

The usefulness of MRI (magnetic resonance imaging) was evaluated in the diagnosis of the mediastinal invasion of esophageal cancer. MR examination was performed in 30 subjects without esophageal diseases and 23 patients with esophageal cancer. Normal esophagi and cancers were well visualized using T1-weighted image. In the axial section, every normal esophagus was contact to the aorta in the angle of less than 30 degree of the aortic circle. When the contact angle was less than 30 degrees, the stage of the cancer was below a1. When the angle was 30 degrees or greater, the stages were ranged from a0 to a3. In the oblique section orthogonal to the contact plain between the cancer and the aorta, the depth of the aortic invasion could be estimated. The sagittal scan was also helpful in the diagnosis of the invasion to trachea, left main bronchus and left atrium.

Esophageal Neoplasms↗

PubMed1990

[The role of neutrophils in airway hyperresponsiveness in dogs after ozone exposure].

To determine whether neutrophils are involved in airway hyperresponsiveness after ozone exposure, we studied the effect of neutrophil depletion by cyclophosphamide treatment on ozone-induced airway hyperresponsiveness in seven dogs. Airway responsiveness to inhaled methacholine was determined by modified Astograph (7 Hz oscillation method), and the numbers of neutrophils in the peripheral blood, total cell counts and differential cell counts in BALF were measured before and after ozone exposure, and after ozone exposure of dogs undergoing cyclophosphamide treatment. Ozone exposure was carried out for 2 hrs at an ozone level of 3.07 +/- 0.01 ppm (mean +/- SE), and cyclophosphamide (10 mg/kg) was given intravenously daily for five days starting six days before ozone exposure. There was a significant increase in airway responsiveness to inhaled methacholine after ozone exposure in the seven dogs (p less than 0.001), and the numbers of neutrophils in the peripheral blood and the neutrophil counts in BALF increased significantly after ozone exposure (p less than 0.01). After ozone exposure of dogs undergoing cyclophosphamide treatment, the numbers of neutrophils in the peripheral blood decreased significantly (p less than 0.001) and the neutrophil counts in BALF did not increase, but the airway responsiveness to inhaled methacholine increased significantly (p less than 0.01). There was no significant correlation between the degree of the increase in airway responsiveness and the degree of the increase in neutrophil counts in BALF after ozone exposure. These results suggest that neutrophil infiltration into the airway is not necessary for an increase in airway responsiveness after ozone exposure in dogs.

Airway Resistance↗

PubMed1990

[Role of alveolar macrophages and neutrophils in the defense system against infection of Pseudomonas aeruginosa in the respiratory tract and the effect of derivative of muramyl dipeptide].

We investigated the role of alveolar macrophages and neutrophils on the defense system against infection of Pseudomonas aeruginosa (P. aeruginosa) in the lower respiratory tracts of rats. Intratracheal inoculation of formalin-inactivated P. aeruginosa to normal rats showed an increased number of neutrophils in bronchoalveolar lavage (BAL) fluid obtained at 24 hours after the inoculation. This response of neutrophils was induced by intravenous administration of MDP-Lys, which is muramyl dipeptide. Phagocytic activity of neutrophils for P. aeruginosa was higher than that of alveolar macrophages, indicating that neutrophils are essential phagocytes in the defense system against P. aeruginosa infection in the lower respiratory tract. Alveolar macrophages released neutrophil chemotactic factor after phagocytosis of P. aeruginosa. This function of alveolar macrophages was increased by MDP-Lys administration. These results indicated that alveolar macrophages play an important role in neutrophil accumulation by release of neutrophil chemotactic factor after the P. aeruginosa phagocytosis in the lower respiratory tract. Moreover MDP-Lys can amplify the neutrophil-dependent defense system against P. aeruginosa by activation of the alveolar macrophage function in vivo.

Acetylmuramyl-Alanyl-Isoglutamine↗

PubMed1990

[Functional diagnosis of tracheal stenosis and tracheoplasty in non-neoplastic disease].

Over the past ten years we have performed 47 tracheoplasty for non-neoplastic disease. Of the 47 patients, 17 had post-tracheostomy stenosis and 17 tracheobronchial tuberculosis. Non-neoplastic disease causes stenosis in the trachea to various degrees. Provided the lung function of these patients is not reduced, tracheoplasty may not be necessary. Functional diagnosis of the tracheal stenosis is therefore important in determining the indications for tracheoplasty in this condition. Clinically, evaluation of the flow plateau of the flow-volume curve has been utilized as a method for detection of fixed upper airway obstruction and the ratio of FEV1.0 to PEFR is helpful for an assessment of the degree of stenosis. But it has not been explained why the ratio correlates with the degree of stenosis. In this study, fixed-type tracheal stenosis was simulated in seven normal subjects by the use of a mouthpiece with an orifice of variable diameter. We derived the experimental formulae of FEV1.0/PEFR as follows. FEV1.0/Qp = FVC/Qp-e2(FVC/Qp-1.5)/2 Qp = 48.7 alpha 1.12 (1-1.1 alpha) (Qp; the plateau flow of the flow-volume curve) (alpha; the ratio of the cross-sectional area of the stenotic portion to that of normal trachea) The values of FEV1.0/Qp calculated from FVC and alpha using these formulae were equal to or in the neighborhood of the experimental values. On the basis of these calculations we concluded that the ratio FEV1.0/PEFR is helpful in the assessment of the degree of stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1990

[Evaluation of a biliary endoprosthesis using expandable metallic stents].

A biliary endoprosthesis constructed of Gianturco self-expanding metallic stents was placed in twenty-nine patients with obstructive jaundice, 27 malignant and 2 benign. All endoprostheses were placed successfully. External drainage catheters were removed in twenty-seven patients. At the follow-up, ranging from two to 59 weeks, the 30 day mortality rate was 7.4%. Twenty-eight patients had obvious clinical improvement with relief of jaundice. Seven patients experienced recurrent jaundice. In two of these patients, the obstruction was relieved by additional metallic stents. The expandable metallic biliary endoprosthesis is suggested as an effective treatment for biliary obstruction.

Adult↗

PubMed1990

[A case of cholesteatoma extending into the medial petrous bone].

A case of facial nerve palsy caused by cholesteatoma was reported. High-resolution CT was very excellent in delineating the mass extension and bony destruction. The labyrinthine segment of facial canal was thought to be the route of spread of cholesteatoma to the medial petrous bone as this case of poor pneumatized petrous bone.

Adult↗

PubMed1990

[Development of Tc-99m labeled activated carbon microspheres and clinical application].

We have developed Tc-99m labeled activated carbon microspheres (99mTc-CH44) for use in mammary lymphoscintigraphy and detailed analysis of mammary lymph flow. 99mTc-CH44 was prepared according to the EDTA complex method. The labeling rate immediately after preparation was 97.7 +/- 2.6% at 37 degrees C and was 94.9 +/- 2.6% after 24-hour continuous shaking. The release of 99mTcO4- from 99mTc-CH44 was determined in vitro, using a simulation model. In this assay, the 99mTcO4- release rate in one hour was 6.6% and that in 6 hours was 38%. When 2ml (2mCi, 74MBq) of 99mTc-CH44 was injected into the mammary glands of 12 patients with breast tumors, the axillary, subclavian and parasternal lymph nodes of 10 patients were visualized 60 minutes later. In analysis of lymph flow in 25 rats using 99mTc-CH44 the lymph flow from the foot pad through the popliteal to the intraperitoneal lymph nodes was known to have only one route when examined by gross finding and histology. However, the examination using RI-technique indicated two routes. The examination in 9 patients with breast cancer indicated that the use of 99mTc-CH44 allowed detailed analysis of lymph flow. These results suggest that 99mTc-CH44 is useful for the preoperative mammary lymphoscintigraphy and detailed analysis of mammary lymph flow.

Adult↗

PubMed1989

Isolation of a gene that encodes a new retinal protein, archaerhodopsin, from Halobacterium sp. aus-1.

We have cloned and sequenced the gene that encodes archaerhodopsin, a light-driven H+ pump in Halobacterium sp. aus-1 (Mukohata, Y., Sugiyama, Y., Ihara, K., and Yoshida, M. (1988) Biochem. Biophys. Res. Commun. 151, 1339-1345). The nucleotide sequence of this gene contained an open reading frame which corresponded to a protein of 260 amino acids with a molecular mass of 27,851 daltons, including a precursor sequence of 6 amino acids at the amino terminus and 2 amino acids at the carboxyl terminus. The deduced amino acid sequence of archaerhodopsin exhibited 59 and 32% homology to the sequences of bacteriorhodopsin and halorhodopsin, respectively, from Halobacterium halobium. Three charged residues (Asp-121, Asp-218, and Lys-222) are conserved in the transmembrane segments among the three retinal proteins. Residues Asp-91 and Asp-102 which, it has been suggested, may be essential for the pumping of protons (Mogi, T., Stern, L. J., Marti, T., Chao, B. H., and Khorana, H. G. (1988) Proc. Natl. Acad. Sci. U. S. A. 85,4148-4152) are conserved between archaerhodopsin and bacteriorhodopsin.

Amino Acid Sequence↗

PubMed1989

[Partial volume effect in MRI--a phantom study].

According to the direction and the thickness of the imaging slice in tomography, the border between the tissues becomes unclear (partial volume effect). In the present MRI experiment, we examined border area between fat and water components using phantom in order to investigate the partial volume effect in MRI. In spin echo sequences, the intensity of the border area showed a linear relationship with composition of fat and water. Whereas, in inversion recovery and field echo sequences, we found the parameters to produce an extremely low intensity area at the border region between fat and water. This low intensity area was explained by cancellation of NMR signals from fat and water due to the difference in the direction of magnetic vectors. Clinically, partial volume effect can cause of mis-evaluation of walls, small nodules, tumor capsules and the tumor invasion in the use of inversion recovery and field echo sequences.

Magnetic Resonance Imaging↗

PubMed1989

Uni-site catalysis by Escherichia coli F1-ATPase with different numbers of bound nucleotides.

We prepared two types of E. coli F1 by slightly different gel filtration procedures of the purified F1: F1(II) contained about 2 mol, and F1(V) about 5 mol of bound adenine nucleotides per mol of the enzyme. Thus F1(II) had more than 2, possibly 3, vacant catalytic sites, while F1(V) had less than one vacant catalytic site. The rate of ATP hydrolysis in uni-site catalysis (in the presence of inorganic phosphate) was about 3-fold higher with F1(II) than with F1(V), suggesting that ADP and inorganic phosphate bound at the catalytic sites of F1(V) changed the kinetics of uni-site catalysis significantly.

Adenine Nucleotides↗