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Biomedical subjects

M Yamamura

Publications and source records attributed to M Yamamura.

At least 199 records · Page 11Linked to original sources

The isoelectric focusing pattern of desialylated alpha 1-antichymotrypsin of heterozygous alpha 1-antichymotrypsin deficiency and of acute phase plasma.

In an attempt to find a molecular marker for the putative abnormal allele in heterozygous alpha 1-antichymotrypsin (ACT) deficiency (a rare trait associated with early emphysema, childhood asthma and chronic "cryptogenic" liver disease) the isoelectric focusing pattern of neuraminidase treated plasma samples from subjects of ACT deficiency families as well as acute phase plasma were compared. There was no difference in the isoform pattern of plasma from ACT deficiency heterozygotes, normal subjects or patients with acute phase response. However, in acute phase plasma there was a disproportional increase in two isoforms, one of which conceivably may be used to mark the early phase of the acute phase response.

Acute-Phase Reaction↗

Heat production as a quantitative parameter for cell differentiation and cell function.

Heat production was measured in relation to cell differentiation and phagocytie function using cells of human monocyte-histiocyte cell line U937. U937 cells differentiated monocytic phagocytes when cultured with lymphokine. Heat production increased as result of differentiation and phagocytosis. An important finding was that the heat increase in differentiated cells and during phagocytosis was directly proportional to the concentration of lymphokine. This strongly suggested that heat production is a quantitative parameter not only for cell differentiation but also for phagocytic function. The measurement of heat produced by mammalian cells can therefore be used to quantitate the differentiation and function of cells.

Body Temperature Regulation↗

Heat production due to intracellular killing activity.

Using Saccharomyces ceravisiae, Candida albicans and Stapylococcus aureus, heat production during phagocytosis was measured in U937 cells which are capable of differentiating to monocytic phagocytes. No increase in heat production of non-differentiated U937 was observed since they were not phagocytic cells. However after differentiation to monocytic phagocytes by lymphokine, U937 cells produced a remarkable amount of heat during phagocytosis. Although Ehrlich ascites tumor cells sensitized with antibody were capable of engulfing S. aureus, no increase in heat nor in superoxide anion production during phagocytosis was detected. It was also found that no heat increase occurred in neutrophils from a patient with chronic granulomatous disease (CGD). It can thus be concluded that the heat production during phagocytosis is due to the intercellular killing process of phagocytic cells.

Animals↗

A study of recording accuracy in linear measurements displayed by sirognathograph.

The recording accuracy of Sirognathograph (Siemens, West Germany) was conducted by means of an experimental apparatus. Diagrams of mandibular border movements in three dimensional directions were performed. The results showed the distortion was not recognized within 5 mm of primary condition in a subject, but slightly between 5 mm and 10 mm. In a distance of more than 15 mm, a considerable distortion was increased until at the maximum opening position.

Dental Equipment↗

[Three-dimensional morphological analysis for craniofacial deformity].

Morphological analysis of the craniofacial deformity has been performed by cephalometric radiography, but even with this method, it is difficult to analyze the cases with complicated deformity. The purpose of the present study is to develop the new 3-D CT morphological analyzing system in order to investigate complicated craniofacial deformity. Using the 67 landmarks, we established the 3 D line drawing method. Then the reproducibility of the landmarks were examined and the clinical cases were investigated. The measurement of landmarks were carried out 10 times by the same operator, and standard deviation of 67 landmarks were calculated. Some landmarks which were difficult to identify showed high value of standard deviation. However, it was almost same value between standard deviation of most of the landmarks and the CT system error. Therefore, location of landmarks in the system were found to be reproducible. This new analyzing system was performed in clinical cases with craniofacial deformity. In such cases, cranium deformity and complicated deformity such as twist-form arrangement of cranium, maxilla and mandible were detected. The 3-D CT morphological analysis is effective for analyzing severe craniofacial deformity which was impossible to recognize with conventional cephalometric analysis.

Cephalometry↗

[A study on display and accuracy of occlusal contacts by means of T-Scan System].

The various methods were introduced in the daily prosthodontic field evaluating occlusal contacts for diagnosis and analysis. Maness in 1987 developed the T-Scan system, which is considered as a new computerized device capable to interpret occlusal contacts information quantitatively. The system is composed of a sensor, sensor frame, handle, cable and system unit. Record and analysis mode made possible the occlusal contacts in three ways, such as the balance plot, the time display and comparison screen. However, accuracy and reproducibility of occlusal marking through this system is still uncertain. Therefore, this preliminary study was conducted on four specific points loaded on a sensor by application of the weight of 0.1 kg through 10 kg. The following results were obtained 1. There exists certain non-sensible areas caused by its constructional feature. 2. The most sensible area can be measured from 0.1 Kg to 2.1 Kg, and therefore, this device is more suitable for recording within lower loadings. 3. Although the system has a certain disadvantage of reproducibility, this contributes to attain diagnosis and treatment of occlusal contacts for a quantitative evaluation.

Dental Occlusion↗

[Primary liver cancer coincident with schistosomiasis japonica].

The etiologic relationship of a parasitic liver disease to primary liver cancer has long been debated, and reported is a case that has been encountered of a primary liver cancer coincident with Schistosomiasis japonica. A fifty-nine year-old-man was diagnosed as having a primary liver cancer complicated with liver cirrhosis. A posterior segmentectomy was performed and a microscopic examination revealed a primary liver cancer with multiple ovae of Schistosoma japonicum in the fibrous stroma of the portal spaces. Discussed is the etiologic relationship of Schistosomiasis japonica to the primary liver cancer.

Carcinoma, Hepatocellular↗

[A double cancer of the gallbladder and common bile duct associated with an anomalous arrangement of the choledocho-pancreatic ductal junction--a case report and a review of the literature].

Reported is the case of a 65-year-old woman who complained of general fatigue and itching. The cancer of the gallbladder and the common bile duct associated with anomalous arrangement of choledocho-pancreatic ductal junction was diagnosed after examination by ERCP, PTCS, US, and CT. The cancer of the common bile duct had metastasized to the pancreas, the portal vein, and the regional lymph nodes and was unresectable. It is well known that an anomalous arrangement of the choledocho-pancreatic ductal junction is highly associated with a cancer of the common bile duct or the gallbladder. But a case that is associated with double cancers is rare and only 6 cases have been reported in the Japanese literature. In addition to a discussion of this case, the literature is reviewed.

Aged↗

Quantitative analysis of nodal involvement with respect to survival rate after curative gastrectomy for carcinoma.

We investigated whether or not the survival rate after curative gastrectomy was related to the total number of lymph nodal metastases and the frequency of the metastases (number of nodes with metastases among number of dissected nodes) in 433 patients with carcinoma of the stomach. Of these patients, 45.3 per cent had lymph nodal metastases, and of a total of 10,130 dissected lymph nodes, 13.0 per cent had metastases. The present findings suggest that both the number and frequency of lymph nodal metastases are closely related to other prognostic factors, such as depth of invasion, histologic type, gross findings, histologic staging and vascular invasion. The five year survival rate significantly decreased as the number and frequency of metastases increased. Thus, it appears the number and frequency of involved lymph nodes are parameters of prognostic significance.

Gastrectomy↗

Ultrastructural alterations in Saccharomyces cerevisiae cells in association with elevated temperature-induced autolysis.

By means of the freeze-etching technique ultrastructural alterations in Saccharomyces cerevisiae cells undergoing autolysis at elevated temperature were studied. Wall surfaces of intact cells were smooth. During autolysis wall surfaces became rough with granules of 20-40 nm diameter. This alteration occurred after extensive disintegration of cytoplasmic organelles and after functional and ultrastructural impairments of the plasma membrane, but well before the rupture of the plasma membrane.

Autolysis↗

Alteration of DNA primase activity by phosphorylation and de-phosphorylation of histone H1.

To investigate the effect of histone H1 on DNA primase activity, partially purified DNA primase from mouse FM3A cells was used. It was found that histone H1 dose dependently inhibited DNA primase. Interestingly phosphorylation of histone H1 reduced the inhibitory activity of the histone. However, de-phosphorylation of the phosphorylated histone H1 resumed the inhibitory activity of DNA primase. These findings lead us to the assumption that phosphorylation and de-phosphorylation of histone may regulate the cell cycle by controlling DNA synthesis through reverse inhibition of DNA primase.

Animals↗

A new compact and cell dense continuous culture system.

A new compact and cell dense continuous culture system was developed. The system consisted of a culture bag, which had two compartments separated by a semipermeable membrane, and an external rotator. Cells were cultured in the inner compartment with medium containing serum or the necessary growth factors. The outer compartment was filled with medium without serum or growth factors. The concentration of cells in culture was normally in the order of 10(7). Due to the large number of cells, sufficient carbon dioxide was produced so that use of a CO2 incubator was unnecessary. The medium in the outer part was frequently changed, but no medium changes were necessary in the inner bag. Using this system, a concentrated yield of antibody as well as a large number of cells could be obtained.

Animals↗

Dual inhibitory effect of bredinin.

Bredinin inhibition of cell growth was investigated in the mouse lymphoma cell line L5178Y. Bredinin caused the accumulation of IMP and the reduction of XMP. It was converted to the 5'-phosphate within the cells. Bredinin 5'-phosphate but not bredinin competitively inhibited both IMP dehydrogenase and GMP synthetase. Thus the inhibition of cell growth is probably due to bredinin 5'-phosphate, which inhibits the consecutive enzyme reactions IMP dehydrogenase and GMP synthetase. These inhibitions result in the accumulation of IMP and the reduction of XMP.

Animals↗

A new high-yield continuous cell-culture system for lymphokine-activated killer cells.

We performed basic studies on a new high-yield culture system (concentrate rotary tissue-culture system) for application to adoptive immunotherapy with lymphokine-activated killer (LAK) cells. Using this system, we demonstrated that up to 2 x 10(7) peripheral blood mononuclear cells/ml could be cultured in interleukin-2 with a sufficient recovery rate and cytotoxicity in short-term cultures (6 days). This system can also be used to proliferate LAK cells to four times the initial cell number with sufficient cytotoxicity for 14 days of culture. Thus, this system allows activation of sufficient numbers of cells to conduct clinical trials on humans.

Culture Techniques↗

Angiomyolipoma of the colon: a new entity in colonic polypoid lesions.

A 67-year-old man with angiomyolipoma on the sigmoid colon is reported. The colonic polyp was pedunculated and diagnosed histologically after endoscopic polypectomy. Angiomyolipoma is one of the benign hamartomas arising principally in the kidneys of patients with or without tuberous sclerosis. Extrarenal angiomyolipoma is rare and this may be the first report of colonic angiomyolipoma.

Aged↗