Search PubMed⌕ Search

Biomedical subjects

H Maeda

Publications and source records attributed to H Maeda.

At least 811 records · Page 45Linked to original sources
PubMed1991

[A case of bronchial mucoepidermoid carcinoma in a 8-year-old child treated with right upper sleeve lobectomy].

A 8-year-old boy was admitted to our hospital with complaint of cough and abnormal shadow on chest X-ray. Bronchoscopy and biopsy revealed a bronchial mucoepidermoid carcinoma, which obstructed right main bronchus. Right upper sleeve lobectomy was performed. The histological examination revealed a low grade malignant mucoepidermoid carcinoma. There were no metastases in the mediastinal lymph nodes. He has been healthy with no evidence of recurrence during 4 years after operation.

Anastomosis, Surgical↗
PubMed1991

Pharmacokinetics and optimum dose of disopyramide in patients with chronic renal failure.

The pharmacokinetics and optimum dose for maintenance of disopyramide (DP) which is effective against arrhythmia were studied in patients with chronic renal failure (CRF, n = 10), who had a creatinine clearance (Ccr) less than 30 ml/min. The plasma concentrations (PC) of DP and mono-isopropyl-disopyramide (MDP) an active metabolite of DP, were measured by high performance liquid chromatography. Samples from patients and controls were obtained at 0, 1, 2, 3, 4, 6, 8, 12, 24, 33, and 48 hr after oral administration (OA) of 100 mg DP. The pharmacokinetic parameters were calculated using a two-compartment model. In CRF, the plasma half life (T 1/2) of DP was 5.25 to 22.42 hr (average is 12.45 hr) and that of MDP was 5.09 to 131.66 hr (average is 16.9 hr). In normal controls, the T 1/2 of DP was 6.05 hr, but that of MDP could not be determined the available sensitivity of measurement. T max was 3.11 hr at the total PC of DP and MDP, and C max was 2.48 g/ml on average. In conclusion, the present study revealed that: (1) the PC of a mixture of DP and MDP should rise following OA of DP every 8 or 12 hr in CRF; (2) it is necessary therefore to monitor the accumulation of MDP after rolling OA of DP; and (3) OA of DP every 24 hr can maintain an effective PC.

Administration, Oral↗
PubMed1991

[The effect of aging on respiratory muscle function].

To elucidate the effect of aging on respiratory muscle function, the authors performed respiratory muscle function tests in 116 normal subjects. Respiratory muscle function was evaluated with maximal expiratory mouth pressure at the TLC level (PEmax) and maximal inspiratory mouth pressure at the RV level (PImax). PEmax and PImax in both sexes showed significant correlations with age. PEmax in males was significantly higher than that in females (123.6 +/- 29.7 cmH2O and 79.0 +/- 21.1 cmH2O, p less than 0.01, respectively). PImax in males was also significantly higher than that in females (98.4 +/- 26.0 cmH2O and 71.9 +/- 26.4 cmH2O, p less than 0.01, respectively). PEmax correlated significantly with TLC, and PImax showed a significant inverse correlation with RV/TLC. Furthermore, there was a significant inverse correlation between RV/TLC and age. Our data suggest that inspiratory muscle weakness in aging may be responsible for the increase in RV/TLC.

Adult↗
PubMed1991

[Results of open heart surgery in neonates--comparison between profound hypothermia with circulatory arrest and deep hypothermic bypass].

To investigate factors affecting surgical outcome of open heart surgery in neonates, a retrospective review was carried out on 38 patients operated in the 9 years period from May 1981 to August 1990, in our institution (TAPVR19, TGA7, HLHS7, and others 5). In the former 3 years and 9 month period, 12 patients were operated with the use of profound hypothermia and circulatory arrest (Group I) and in the latest 5 year and 5 month period, continuous deep hypothermic bypass was used in all but for 7 patients with HLHS (Group II). In the group of neonates with TAPVR, operative mortality improved to 7% (1 of 14) in Group II compared to that of 60% (3 of 5) in Group I. CVP and LAP measured immediately after cessation of cardiopulmonary bypass (CPB) were lower in Group II and the value of CPK-MB was significantly lower in Group II. There was a significant negative correlation (r = -0.695, p less than 0.05) between CPB time and urine volume for 72 hours after operation. A significant negative correlation (r = -0.899, p less than 0.01) was also obtained between CPB time and urine volume in the group of 7 neonates with TGA. There was no significant difference in urine volume between patients with TAPVR and TGA despite of significantly longer CPB time in patients with TGA. It is concluded that, 1) improved protection of cardiac and renal function was obtained in neonates operated with the use of continuous deep hypothermic bypass, 2) surgical outcome was influenced by the method of CPB, CPB time and differences in cardiac function ascribed to primary lesions.

Assisted Circulation↗
PubMed1991

[Delay in red blood cell recovery after major ABO incompatible bone marrow transplantation].

In 6 of 27 patients in whom major ABO incompatible marrow was transplanted, the recovery of red blood cells (reticulocyte count greater than or equal to 1%) required more than 50 days after the transplantation. In 3 of them, more than 100 days were required. High titers of pre-transplant anti-A or anti-B agglutinin correlated with the delay in red blood cell recovery (IgM: p less than 0.01, IgG: p less than 0.05). In all of the patients whose pre-transplant IgM titers were 4 or less, and whose IgG titers were 32 or less, the red blood cells recovered within 50 days. Administration of cyclosporine did not correlate with the delay in red blood cell recovery. All the patients finally developed red cell production within 8 months without any treatment.

ABO Blood-Group System↗
PubMed1991

[Measurement of intrahepatic shunt using Rutland method].

Intrahepatic shunt ratio was calculated from the fraction of the uptake constant and the blood background, analyzing the data of 99mTc-(Sn)-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) hepatobiliary imaging by Rutland method. Shunt flow and total hepatic blood flow (THBF) were also calculated from the values for the effective hepatic blood flow (EHBF) estimated from the blood clearance technique. In 15 cases of normal volunteer, the average of the shunt ratio, shunt flow, and THBF were 18.4 +/- 5.4 (S.D.)%, 137.8 +/- 49 ml/min, and 753 +/- 83.2 ml/min, respectively. In 8 cases of chronic hepatitis, the values were 35.2 +/- 2.6%, 276 +/- 55.4 ml/min, and 794.1 +/- 119.4 ml/min, respectively. In 12 cases of liver cirrhosis, the values were 51.4 +/- 12.6%, 353.9 +/- 141.3 ml/min, and 685.6 +/- 174.8 ml/min, respectively. In cases of chronic hepatitis and liver cirrhosis, in comparison with normal cases, the values for the shunt ratio and shunt flow were significantly increased (p less than 0.001) and those for EHBF were significantly decreased (p less than 0.001), but those for THBF were not significantly altered. There was a significant inverse correlation between the shunt ratio and EHBF (r = -0.842) in all 35 cases. This method is considered to be useful for differential diagnosis, estimation of the grade of the diseases, and evaluation of pathophysiology of various diffuse liver diseases.

Chronic Disease↗
PubMed1991

[The influence of the time activity variation on dynamic SPECT images in camera based SPECT].

Image quality of dynamic single photon emission computed tomography (SPECT) using a rotating gamma camera is dependent on the time activity variation of the tracer such as accumulation and excretion in the object's organ. Especially at the early time after injection of radionuclide, artifacts may occur strongly in the SPECT images. Simulated and experimental projection data of line sources and Jaszczak phantom were altered by sequentially weighting the projections with a function that varied linearly with time. With a variation of object activity given by linearly decaying functions, the main effect observed on the SPECT images obtained from simulated line sources was an elliptical deformation on the object. If the changing rate (R (t + 1)-R(t))/R(t) x 100 remained within 20% during acquisition, this deformation of SPECT images of line sources was not noticeable visually and resolution (FWHM) of line sources scarcely was degraded. In renal dynamic SPECT study using 99mTc-DTPA, the image quality of the first scan (30 sec) was considerably degraded. However, the changing rates after the third scan were less than 20% on the mean of 10 kidneys and the image quality was not noticeable visually.

Gamma Cameras↗
PubMed1991

[Clinical efficacy of cefpirome against various infectious diseases in children].

The clinical efficacy and the pharmacokinetics of cefpirome (CPR, HR 810), a new semisynthetic cephalosporin derivative, were investigated in children with various infectious diseases. CPR showed high blood peak levels, relatively long half-life and high levels in urine. Excellent clinical efficacy was obtained in 2/3 cases with pneumonia, 3/4 cases with upper respiratory infection, 2/2 cases with cutaneous and soft tissue infection and 1/1 case with urinary tract infection. The overall efficacy rate was 80%. No clinical adverse effects were observed while slightly elevated GPT and GOT, decreased platelet were detected in 4 cases without clinical problems. CPR should be an useful and safe drug in treating infectious diseases in children.

Adolescent↗
PubMed1990

[Differential diagnosis between nonhyperfunctioning adenoma and adrenal metastasis on adrenocortical scintigraphy].

Adrenocortical scintigraphy using I-131-adosterol was performed in six cases of nonhyperfunctioning adenoma incidentally discovered on CT scans and four cases of adrenal metastasis. In all six cases of nonhyperfunctioning adenoma, there was increased uptake of of the I-131-adosterol on the side of the adrenal mass discovered at CT. In three of four cases of adrenal metastasis, there was no uptake of the I-131-adosterol on the side of the mass detected at CT. Uptake was symmetrical in one case of adrenal metastasis. Adrenocortical scintigraphy is able to differentiate nonhyperfunctioning adenoma from adrenal metastasis in recognition of increased uptake of I-131-adosterol on the side of the adrenal mass discovered on CT scans.

Adenoma↗
PubMed1990

Role of natural killer cells and macrophages in the nonspecific resistance to tumors in mice stimulated with SMANCS, a polymer-conjugated derivative of neocarzinostatin.

Copoly(styrene-maleic acid)-conjugated neocarzinostatin (SMANCS), a lipophilic derivative of the proteinaceous antitumor antibiotic neocarzinostatin, has been reported to stimulate a nonspecific resistance to tumors (NSRT) in solid tumor-bearing mice, in addition to its chemotherapeutic antitumor effect through the arrest of DNA synthesis by direct DNA strand scission. In the present study, splenic or peritoneal effector cells were used to investigate the ability of SMANCS to augment natural killer (NK) cell activity and to generate cytostatic macrophages (A-M phi). Splenic NK cell activity augmented by SMANCS was characterized by cytotoxicity to various target cells, nylon wool nonadherence, and sensitivity to treatment with anti-asialo-GM1 antiserum or monoclonal anti-Thy-1.2 antibody followed by complement. The A-M phi generated by SMANCS stimulation were characterized by their adherence to a plastic surface coated with fetal calf serum and their ability to phagocytize carbonyl-iron. The maximum level of NK cell activity in the spleens of mice was detected 3 days after i.v. injection of SMANCS, and the highest activity of the peritoneal A-M phi was demonstrated in mice 4 days after SMANCS treatment. On the other hand, the NSRT of mice stimulated with SMANCS was not detectable in mice treated with carrageenan or trypan blue, whereas SMANCS-stimulated NSRT was observed in mice treated with anti-asialo-GM1 antiserum. The NSRT that was stimulated with SMANCS was also demonstrated in mice homozygous for the beige mutation and their non-beige littermates, when NK cell-resistant EL-4 thymoma was used as a tumor target. These results suggest that the expression of NSRT of mice stimulated with SMANCS may require the function of A-M phi, although NK cell activity was also augmented in spleens of mice by administration of SMANCS.

Animals↗
PubMed1990

[Quantitative assessment of mineral content in metacarpal bone with Fuji computed radiography].

A new microdensitometry method for quantitative assessment of bone mineral content using Fuji computed radiography (FCR) was developed and the results were compared with those obtained by the conventional film-screen method. Using both methods, X-ray pictures of the 2nd metacarpal bone were taken with a reference aluminum step wedge in nine normal subjects and nine parameters representing the width and density of bone marrow and cortex were calculated in the middle of the bone shaft. Interobserver reproducibility assessed for three parameters was significantly higher in the FCR method than the conventional one. The value of sigma GS computed by the FCR method, that is equivalent to the net bone density of the transverse section of the shaft, showed higher correlation with the one obtained by computed tomography in comparison with the conventional method. In our FCR method, moreover, interobserver reproducibility and accuracy was improved by employing automatic manipulation as much as possible in the process of calculation. The exposure dose in the FCR method could be reduced to half of the one in the conventional method without deteriorating the accuracy. In conclusion, our new microdensitometry method with FCR provides high accuracy and good reproducibility for the measurement of bone mineral content with small exposure dose and is likely to be useful for the long-term follow-up of the osteoporotic patients from the variety of causes.

Adult↗
PubMed1990

[Accuracy of detecting stenotic changes on coronary cineangiograms using computer image processing].

To accurately interpret stenotic changes on coronary cineangiograms, an automatic method of detecting stenotic lesions using computer image processing was developed. First, tracing of artery was performed. The vessel edges were then determined by unilateral Gaussian fitting. The stenotic change was detected on the basis of the reference diameter estimated by Hough transformation. This method was evaluated in 132 segments of 27 arteries in 18 patients. Three observers carried out visual interpretation and computer-aided interpretation. The rate of detection by visual interpretation was 6.1, 28.8 and 20.5%, and by computer-aided interpretation, 39.4, 39.4 and 45.5%. With computer-aided interpretation, the agreement between any two observers on lesions and non-lesions was 40.2% and 59.8%, respectively. Therefore, visual interpretation tended to underestimate the stenotic changes on coronary cineangiograms. We think that computer-aided interpretation increases the reliability of diagnosis on coronary cineangiograms.

Cineangiography↗
PubMed1990

Changes in phospholipid composition and phospholipase D activity during the differentiation of Physarum polycephalum.

Changes in phospholipid composition and phospholipase D activity were observed during a differentiation from haploid myxoamoebae to diploid plasmodia of a true slime mold, Physarum polycephalum. In the amoeboid stage, the main components of phospholipid fraction were phosphatidylethanolamine (PE, 43.3%), phosphatidylcholine (PC, 28.8%) and phosphatidylinositol (PI, 8.0%), but in the plasmodial stage, PC was dominant (40.7%) and other main components were PE (31.5%) and phosphatidic acid (PA, 11.0%). The specific activity of phospholipase D in the plasmodia was 5.7-times higher than that in the myxoamoebae when measured in the presence of Ca2+ at the alkaline pH. In the amoeboid stage, phospholipase A activity (A1 or A2) was detected at the alkaline pH with Ca2+. Phospholipase D activity in the plasmodia was characterized: pH optimum was 6.0; Ca2+ was required for the reaction and Ba2+ could substitute partly for Ca2+; PE was the best substrate for the hydrolytic activity and PC and PI were not appreciably hydrolyzed; and all detergents tested inhibited the enzyme activity.

Calcium↗
PubMed1990

Comparison of the cytotoxic effects of the high- and low-molecular-weight anticancer agents on multidrug-resistant Chinese hamster ovary cells in vitro.

Neocarzinostatin (NCS), styrene-maleic acid copolymer-conjugated neocarzinostatin (SMANCS), and ricin exhibited cytotoxicity against two different types of Chinese hamster ovary cells, parental AUXB1 cells and the multidrug-resistant (MDR) subline CHRC5 cells at the nanomolar range. These doses were much lower than those of the other anticancer drugs tested (micromolar range), even after a short incubation. MDR CHRC5 cells were 20 to 900 times more resistant to Adriamycin, aclacinomycin, vinblastine, and mitomycin C than were AUXB1 cells. However, the resistance of CHRC5 cells to NCS, SMANCS, or ricin was relatively low: the 50% colony inhibitory concentration was only 5 to 10 times higher than that for parental AUXB1 cells. CHRC5 cells were not resistant to 5-fluorouracil and cis-diamminedichloroplatinum(II), but the effective doses of these agents to them were 10(3)-10(6) times higher, and longer incubation times were required to produce the same cytotoxicity as NCS and SMANCS. Furthermore, cell-bound NCS, SMANCS, and ricin were not released from AUXB1 or CHRC5 cells during a 120-min incubation, although Adriamycin was excreted very rapidly from CHRC5 cells after binding and internalization. These results strongly suggest that NCS, SMANCS, and ricin, which are internalized into cells by endocytosis, were not excreted from the cells by active efflux and exhibited a pronounced anticancer effect against MDR cells.

Aclarubicin↗
PubMed1990

CP-82,996, a novel diglycoside polyether antibiotic related to monensin and produced by Actinomadura sp.

A new polyether antibiotic CP-82,996 (C50H86O16) was isolated by solvent extraction from the fermentation broth of Actinomadura sp. (ATCC 53764). Following purification by silica gel column chromatography and crystallization, the structure of CP-82,996 was determined by a single crystal X-ray analysis. The structure is closely related to monensin, but is unique in that it contains two sugar groups, whereas monensin has none. The 1H and 13C NMR chemical shifts and assignments for CP-82,996 were elucidated, and they were compared with those determined previously for monensin. CP-82,996 is active against certain Gram-positive bacteria, and is a very potent anticoccidial agent. It effectively controlled chicken coccidiosis caused by several Eimeria species at 5-10 ppm in feed, and is 10-20 times more potent than monensin.

Animals↗
PubMed1990

CP-60,993, a new dianemycin-like ionophore produced by Streptomyces hygroscopicus ATCC 39305: fermentation, isolation and characterization.

CP-60,993, 19-epi-dianemycin, is a novel polycyclic ether antibiotic produced by Streptomyces hygroscopicus ATCC 39305. Fermentation recovery, purification and crystallization were achieved using standard procedures. CP-60,993 was characterized as a monocarboxylic acid. Elemental analysis suggested a molecular formula of C47H78O14 for the free acid and C47H77O14 Na for the sodium salt. Crystalline from CP-60,993 sodium salt shows the following properties: m.p. 193-205 degrees C, E1%(1 cm) = 157 at 232 nm, [alpha]25 degrees C(D) + 11.0 (c 1, methanol). The structure, determined by MS, PMR and CMR, differs from dianemycin only in the stereochemistry at position 19. This was confirmed by X-ray crystallography carried out on the rubidium salt of CP-60,993. It exhibited activity in vitro against Gram-positive and anaerobic bacteria, efficacy against Eimeria coccidia in vivo in poultry, and stimulation in vitro of rumen propionic acid production.

Aminoglycosides↗