Biomedical subjects
Publications and source records attributed to K Masuda.
Chondromas of the nasal septum are rare. A case of chondroma originating in the left side of the nasal septum is reported. The patient, a 61-year-old female, presented bilateral nasal obstruction, headache, and nasal bleeding. The tumor was removed surgically through the transpalatal approach under general anesthesia. No recurrence was noticed after 6 months follow-up.
Mesosomes of Staphylococcus aureus 209P were observed to be extruded as tubules upon protoplast formation by electron microscopy and isolated under hypertonic conditions to maintain their structural integrity by differential centrifugation followed by sucrose density gradient centrifugation. Isolated mesosomes were composed of long, branched tubules of irregular sizes and they were shortened during purification. Thin sections of isolated mesosomes showed that the mesosomal tubule was surrounded by a triple-layered membrane and contained ribosome-like particles in diameter of about 15 to 20 nm. These particles were isolated from purified mesosomal preparation by disrupting the mesosomal tubule with deoxycholate and Triton X-100 under hypotonic conditions followed by a linear sucrose density gradient centrifugation. Negatively stained preparations of the isolated particles revealed the same appearance as those of the ribosomes isolated from the cytoplasm. The mesosomal particles sedimented at 70S in sucrose gradients in the presence of 10 mM Mg2+, but they were dissociated into two subparticles, 50S and 30S subunits, upon lowering the Mg2+ concentration to 1 mM. These findings indicate that the mesosomal tubule is packed with ribosomes.
Mesosomes were isolated and purified from Micrococcus luteus under hypertonic conditions throughout preparation processes. The purified mesosomal preparation was composed of closed tubules and vesicles. Electron-dense ribosome-like particles were observed within the isolated mesosomal vesicles by electron microscopy. The ribosome-like particles were isolated from the purified mesosomes by a procedure involving solubilization of the membranes with detergents followed by centrifugation on a linear density gradient of sucrose. The isolated particles have a sedimentation coefficient of 70S in the presence of 10 mM Mg2+, when Mg2+ concentration was lowered to 0.1 mM, the particles were dissociated into two sub-particles of 30S and 50S. The 70S particles had the same appearance as cytoplasmic 70S ribosome particles upon observations of negatively stained preparations. These findings indicate that mesosomal tubules contain ribosomes. The isolated mesosomal ribosomes had the ability for protein synthesis when polyuridylic acid-directed polyphenylalanine synthesis was assayed. The sensitivity of mesosomal ribosomes to inhibitors, chloramphenicol and streptomycin, for protein synthesis was significantly lower than that of both cytoplasmic and cytoplasmic membrane-bound ribosomes. In addition, three penicillin-binding proteins were detected in the mesosomal membranes. One of these was localized predominantly in the mesosomal membranes and the other two were distributed almost equally in both mesosomal and cytoplasmic membranes.
A case of Sweet's syndrome is reported in a patient with Behçet's disease. This association has not been reported outside Japan. The relationship of the two diseases is discussed.
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We examined the efficacy of a new commercial assay procedure (SCC RIABEAD) for estimation of squamous cell carcinoma related antigen (SCC). Intraassay and interassay variance were 4.0-14.6% and 4.6-17.0% respectively. Recovery and dilution tests gave satisfactory results. The normal range was under the level of 1.63 ng/ml. The patients with uterine cervical cancer or squamous cell carcinoma of the lung showed high positive rates. The values of SCC measured by SCC RIABEAD were well-correlated to those by SCC RIAKIT. However, SCC RIABEAD showed lower values in low SCC level and higher values in high SCC level than SCC RIAKIT.
The analysis of kinetic rate constants in the compartment model for [18F]fluorodeoxyglucose (FDG) was undertaken. Four kinetic rate constants were determined with a least square fitting package SALS (Statistical Analysis with Least Squares), using the measured data of 18F activity as a function of time. SALS calculations were found to be easy and quick with high precision. The rate constants and the curves fitted by the k3 and the k4 models were compared in situations with various degree of cerebral glucose metabolism during positron emission tomography (PET) studies. The k4 model in the determination of cerebral metabolic rate for glucose (CMRglu) was much superior than the k3 model in any given situation as it always underestimates the metabolic rate. However, the k3 model produces less variation when the cerebral radioactivity curve shows steady rising pattern.
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The antitumor activity of a novel ansamycin antibiotic, trienomycin A, against various murine tumors was studied with two treatment schedules. The intraperitoneal injection of the antibiotic showed remarkable antitumor activity on sarcoma 180 and P388 leukemia at doses of 160 or 320 mg/kg, showing 151% and 100% increase in life span, respectively. Trienomycin A inhibited the growth of Ehrlich and Meth A cells in vitro at doses of 0.1-0.4 microgram/ml when the cells were exposed to the antibiotic for 72 hours. The incorporation of [3H]thymidine into acid precipitable material in HeLa cells was slightly more marked than that of [3H]uridine and [3H]leucine when the cells were exposed to 0.04 or 0.08 microgram/ml of trienomycin A for 4 hours. It appeared that trienomycin A showed antitumor activity by direct cytotoxic action.
A retrospective study was made of 433 patients with colorectal cancer who were operated on between January, 1971 and September, 1986. Two-hundred and forty-eight synchronous polyps (226 adenomas and 22 carcinomas) were found in 128 patients (29.6%). The incidence of polyps varied according to the patient's age, sex, family history of colorectal cancer, and also according to the macroscopic classification, depth of infiltration, and the number of the primary tumors. Of these, macroscopic classification seemed to be the most important factor determined by multivariate analysis. The incidence of synchronous polyps of the protuberant type were the highest (50%), as compared to the ulcerating type (28%) and the infiltrating type (19%) (p less than 0.03).
Prostaglandins (PGs) and their derivatives have been reported to modulate or inhibit a variety of tumor cells in vitro and in vivo. In the present study, an established retinoblastoma cell line, Y-79, was investigated for 1) its capacity to synthesize PGs and 2) its susceptibility to PGs and their derivative, 64E, exogenously given. The capacity of Y-79 cells to produce PGs was estimated by thin layer chromatography using [1-14C] arachidonic acid as a substrate, and it was found that no detectable amounts of PGD2, PGE2, PGF2 alpha, thromboxane B2, or 6-keto PGF1 alpha were produced by Y-79 cells. Furthermore, the effects of exogenously given PGs (PGA1, A2, D2, E1, E2, F2 alpha, and J2) and 64E on the cell proliferation of Y-79 cells in culture were examined. PGE1, E2, and F2 alpha showed no significant effects on the cell growth of Y-79 cells at all tested doses (1-20 micrograms/ml). On the other hand, PGA1, A2, D2, and J2, and 64E remarkably inhibited the cell growth of Y-79 cells. A dose-response study indicated that 64E was the most effective among these drugs, followed by PGJ2. PGD2, A1, and A2 were less effective than PGJ2. The present data demonstrate that Y-79 cells do not produce endogenous PGs, and that these cells are highly susceptible to exogenous PGs (PGJ2, D2, A1, and A2) as well as 64E.
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The purpose of this study was (1) to analyze the factors responsible for errors in the two-dimensional Doppler echographic measurements of cardiac output (C.O.) and (2) to establish a noninvasive method for measuring C.O. The subjects were 50 cardiac patients who had neither aortic valve disease nor intracardiac shunts. The C.O. was calculated using the following formula: C.O. (l/min) = mean flow velocity (cm/sec) x pi(aortic ring diameter/2)2 (cm2) x 60/10(3) Left ventricular ejection flow velocity was recorded in the center of the aortic ring from the apical approach. Mean velocity was calculated by integration of instantaneous mean velocity in the ejection phase divided by the cardiac cycle length, and was corrected by the Doppler incident angle. The inner diameter of the aortic ring was measured in the parasternal long-axis view at the time of the maximum ejection flow velocity. The following results were obtained: 1. Sources of error in the measurement of cardiac output. 1) Accuracy of instantaneous mean velocity calculating circuit: This calculating circuit was accurate in model experiments using pulsatile flow. 2) Effect of high-pass filter: In model circuits, application of high-pass filter overestimated flow velocity. The higher the cut-off frequency of the high-pass filter, the larger the overestimation. This was probably due to the parabolic flow velocity profile in the circuit. 3) Flow velocity profile in the aortic ring: The flow velocity profile seemed to be flat in the aortic ring except near the anterior aortic wall. Therefore, the effect of the high-pass filter was considered to be negligible in case of clinical application. 4) The effects of shift and size of sample volume: The location of sample volume relative to the aortic valve ring shifted about 7 mm during systole. However, the shift and size of sample volume seemed to have little effect on the measured C.O., because the flow velocity profile was nearly flat in the aortic ring. 5) Ultrasound beam incident angle: From a practical viewpoint, it was necessary to set an incident angle of less than 50 degrees for minimizing the error. We were able to set the angle within 50 degrees in all but one of patients. 6) Diameter of the aortic ring: Two-dimensional echographic measurement of the aortic ring diameter was not so accurate; it seemed to become a major source of error in the calculation of C.O.(ABSTRACT TRUNCATED AT 400 WORDS)