Biomedical subjects

T Ashihara

Publications and source records attributed to T Ashihara.

At least 19 recordsLinked to original sources

PubMed1992

[Progress in microscopic image analysis and the trend of image cytometry].

Image cytometry has recently developed prominently based on the digital imaging of cell morphology brought about by great advances in microcomputer hardware and software, electronics etc. This method is characterized by the quantitation of both the amount of intracellular bioactive materials and cell morphology, and is expected to further advance many cell analysis techniques involving automated cytology, chromosome image analysis, automated histopathology, viable cell analysis, 3D image construction, etc. The present use is still minimal, and advances in both hardware and software for cyto-histologic recognition are essentially necessary. Perhaps by the end of this century, more sophisticated and faster machines for automated cyto-histologic analysis will appear, replacing many microscopic techniques of presently subjective observation in the biomedical field.

Cell Cycle↗

PubMed1992

[The usefulness of dipyridamole stress myocardial scintigram as a preoperative test for detecting ischemic heart disease before vascular surgery].

We evaluated the usefulness of dipyridamole 201Tl myocardial scintigraphy (DS) for detecting myocardial ischemia in 18 candidate for vascular surgery. DS indicated significant thallium redistribution in 6 patients. Coronary angiography was performed in 5 of these 6 patients and revealed significant coronary artery disease in all patients. As a result, operation was cancelled in 4 patients with severe coronary artery disease. One of these cases died of acute myocardial infarction after being discharged from hospital. One other patient was operated after percutaneous transluminal coronary angioplasty. Another patient was operated knowing that he had significant but mild coronary artery disease. Subsequently, operations were performed in 14 patients. No serious cardiac event occurred in these 14 patients except one case with T wave inversion without myocardial enzyme elevation. Thus, we concluded that DS was a useful method for detecting ischemic heart disease and prevent cardiac event associated with vascular surgery.

Aged↗

PubMed1992

[Analysis of cell proliferation kinetics and the effects of cisplatin on the cell cycle of human gastric cancer cells by autostage cytofluorometry].

Analysis of both cell proliferation kinetics and effects of cis-diamminedichloroplatinum (CDDP) on cell cycle in human gastric cancer cell line (HGC-Y2) by measuring the contents of nuclear DNA, RNA and the Ki-67 antigen using autostage cytofluorometry system was described. In HGC-Y2 cells, RNA content increased during the cell cycle and reached to the maximum at G2/M phase. The results of pulse treatment with CDDP on these cells demonstrated a prolongation of S phase and G2 arrest with increasing of RNA content of these cells. We classified the cells by intranuclear distribution pattern of Ki-67 antigen and thus could identified the cells at G0 and M phases from these classification. The content of Ki-67 antigen was moderate grade at G1 phase and it decreased in the early S phase, then increased gradually during S phase and at the late S phase. It increased rapidly, reaching to the maximum at G2/M phase. After CDDP treatment, the content of Ki-67 antigen increased in the cells in prolonged S phase and in the cells arrested at G2 phase. It was also found that the syntheses of both Ki-67 antigen and RNA were not inhibited by CDDP. These results suggest that the method using autostage cytofluorometry system was useful for the research, on the mechanism of cancer therapy because of making possible to analyze precisely the cell cycle and the influence of anticancer drugs.

Cell Cycle↗

PubMed1991

Pleomorphic xanthoastrocytoma. Ultrastructural, immunohistochemical, and DNA cytofluorometric study of a case.

A case of right frontal pleomorphic xanthoastrocytoma that occurred in a 7-year-old boy is reported clinicopathologically. The patient underwent surgery on September 29, 1988. Histologic diagnosis of pleomorphic xanthoastrocytoma was made because, in addition to the unique pleomorphic histologic features, positive glial fibrillary acidic protein in immunohistochemical staining and characteristic ultrastructural features, i.e., cytoplasmic intermediate fibrils and lipid vacuoles, basal lamina, and abundant reticulin networks were demonstrated. The DNA cytofluorometric analysis of the nuclei of the tumor cells disclosed the main mode to be diploid with polyploid classes (4, 8, 16, and 32C) without any aneuploidy. Despite the presence of many pleomorphic nuclei, DNA histogram of the tumor disclosed very few DNA synthetic cells indicating a biologically inactive nature of the tumor. The patient is still alive and totally asymptomatic 20 months postoperatively.

Astrocytoma↗

PubMed1991

[The examination of DNA strand breaks induced by peplomycin-using non-radioactive in situ nick translation method].

In situ nick translation (ISNT) is a method to detect DNA single strand break (nick) at each cellular level. In this study, peplomycin (PEP)-induced DNA strand breaks and its repair were examined using non-radioactive ISNT method. Human fibroblasts were cultured with various concentrations of PEP for different durations, and then DNA strand breaks were evaluated by ISNT method. The signal intensity of DNA strand breaks of the PEP-treated fibroblasts was increased in a dose dependent manner. At the fixed concentration of PEP, it reached to a maximum level after 10 min. of culture and remained unchanged for at least 24 hours. In addition, DNA strand breaks induced by PEP was rapidly repaired in 10 min. after washing. Thus, the non-radioactive ISNT is thought to be a quick, sensitive and specific method not only to detect DNA strand breaks but also to observe its repair.

Bleomycin↗

PubMed1991

[Staining of bone canaliculi using decalcified bone tissues].

Recently we were able to stain bone canaliculi using the decalcified bone tissues, according to a modified method of the Bodian staining method, which is commonly used for staining the nerve fibers with silver impregnation of protargol. The bone tissues from normal rabbits, rats, and humans were decalcified with buffered EDTA solution after 10% formalin fixation. The tissues were embedded in paraffin and were sliced at 4 microns then the sections were attached to the gelatin-coated glass slides. These sections were treated first with potassium dichromate followed by 2% protargol solution containing copper. After gold chrolide treatment, they were immersed in oxalic acid. Both the lacunae and canaliculi of osteocytes were stained black in sharp contrast to bone matrix of red purple. Using the present staining method, the bone canaliculi were clearly detectable in fine details without producing apparent artificial damage of soft tissues. The canaliculi showed also markedly complex fine structures. By combining the present staining method with eosin or toluidine blue staining, we were able to recognize even immature osteocytes in enchondral ossification at growth cartilage with fine bone canaliculi. From these results, we conclude that the present method is very useful in histopathological studies of the lacuna-canalicular system of osteocytes in the decalcified bone tissues.

Animals↗

PubMed1991

[A case of lupus erythematosus preceded by right heart failure due to pulmonary hypertension].

A 40-year-old woman was admitted because of increasing exertional dyspnea. Right heart failure was suggested by the presence of hepatomegaly, pretibial edema and also echocardiographic findings. Physical examination and echocardiography showed no evidence of valvular disease or congenital heart disease except for right ventricular dilatation and tricuspid regurgitation. The ventricular septum deviated toward the left ventricle throughout the cardiac cycle, but left ventricular function was preserved. Severe pulmonary hypertension averaging 44 mmHg was revealed by cardiac catheterization. Digital subtraction angiography and pulmonary blood flow scintigraphy showed no evidence of pulmonary artery embolism, and no interstitial pulmonary lesions that might have caused pulmonary hypertension were recognized. Hypergammaglobulinemia suggested an autoimmune disorder, and signs of systemic lupus erythematosus (SLE), such as pleural effusion, proteinuria, lymphocytopenia, LE cell phenomenon and antinuclear antibodies were present. Several autoimmune diseases are known to be causative factors of pulmonary hypertension. However, only ten cases of SLE complicated by pulmonary hypertension have been reported the present one. These cases were characterized by a high incidence of Raynaud's phenomenon and positivity for anti-RNP antibody. In our present case, SLE activity was suppressed using prednisolone, but pulmonary hypertension persisted and the patient eventually died due to right cardiac failure. Judging from the clinical course of the ten reported cases of SLE-pulmonary hypertension, there seems to be no hope of improving the pulmonary hypertension once it has become established. Therefore it is important to detect and cure pulmonary hypertension as early as possible.

Angiography, Digital Subtraction↗

PubMed1991

[The distribution of S-100 protein positive chondrocytes in the human articular cartilages under aging or diseased conditions].

There have been few reports on the localization of S-100 protein positive chondrocytes in the human articular cartilages. We studied 59 articular cartilages of the aged subjects, 65 osteoarthritic (OA) and 39 rheumatoid arthritic (RA) articular cartilages, to detect the histological localization of S-100 protein using immunoperoxidase method (ABC). The results obtained from normal cartilages demonstrated strongly positive cells representing hypertrophic chondrocytes in the perivascular areas of the neonatal articular cartilage and in the deep zone of the infant articular cartilage. The moderately positive cells were found in the intermediate zone of infant and adult articular cartilages. In mild OA, there were many positive chondrocytes in the intermediate zone with erosion of the surface layer, while in moderate or severe OA many strongly positive cells were found in clusters. The hypertrophic cells in the metaplastic cartilage arising from bone marrow in subjects with severe OA, or from pannus after RA were also positive. It is therefore, suggested that S-100 protein may be correlated with the metabolic activity of the cartilage matrix such as collagen and proteoglycan, as reported in the literature. S-100 protein further, appears to be useful for evaluating histologically the activity of cartilage repair in the pathologic human articular cartilages.

Adolescent↗

PubMed1991

[Cytofluorometric analysis of cell proliferation kinetics of the human colorectal cancer].

In order to clarify cell proliferation kinetics of human colorectal cancer, 91 cases were investigated by cytofluorometry and clinicopathological findings. The results showed colorectal cancers could be divided into 3 groups according to the ploidy pattern. Group I was the diploid cell population, group II the polyploid cell populations and group II' the aneuploid cell populations. These ploidy patterns were found not to be related both to the histological types and the gross pathological classification. Most of the intramucosal cancers were found in group I, and the cancers of more advanced growth mainly in groups II and II'. The fraction of diploid cells in the groups I and II' did not show the remarkable change, but in the group II decreased with tumor progression. These results indicate the ploidy patterns appear to change with the submucosal invasion, and also that while the ploidy patterns in the groups I and II' are stable, those in the group II increase the extent of polyploidization with the tumor growth. Lymphatic metastases were found to be more frequent in the group II than in the groups I and II'. It is suggested that the mechanism of lymphatic metastasis would be related to the cell polyploidization.

Adenocarcinoma↗

PubMed1991

[Evaluation of percutaneous transhepatic gallbladder drainage (PTGBD) for acute cholecystitis].

We performed percutaneous transhepatic gallbladder drainage (PTGBD) in 71 of 129 patients with acute cholecystitis. In 70 of 71 patients, clinical symptoms and laboratory data were rapidly improved by PTGBD. In order to evaluate the degree of acute cholecystitis, the clinical symptoms, laboratory data and ultrasonographic findings of these patients were analyzed by the quantification theory of Hayashi. As a result, irregular thickening of the gallbladder wall and gallbladder swelling presented by US and physical findings with Blumberg's sing or defence in the abdomen were most important findings to assess the severity of acute cholecystitis. Based on these data, we originally introduced the Severity Score of this disease and used it a criterion of PTGBD indication. The patients with the score above 0.5 were considered to be indicative for emergent PTGBD. In high risk patients (e.g., the aged or of diabetes mellitus) with the score above 0, this procedure should be indicated. In 24 of 71 patients, Percutaneous Transhepatic Gallbladder Scope (PTGBS) were attempted to retrieve stones, and it was completely successful in 16 patients.

Acute Disease↗

PubMed1991

[Preoperative diagnosis and staging of pancreatic cancer by endoscopic ultrasonography (EUS)--a comparative study with other diagnostic tools].

Endoscopic ultrasonography (EUS), ultrasonography (US), computed tomography (CT), and angiography (Angio) were performed in 26 patients with pancreatic cancer which were all resected. Preoperative findings of each diagnostic tools were compared with histological findings. In order to discuss the effectiveness of each body imagings, the preoperative staging of pancreatic cancer was evaluated in direct invasion to the anterior pancreatic capsule and stomach (S), direct invasion to the duodenum (D), direct invasion to the retroperitoneal adjacent vessels (Rp), and regional lymph node metastasis (N). The overall accuracy rate was 77% with EUS (50% with US, 38% with CT, 56% with Angio) in S, 81% with EUS (44% with US, 38% with CT, 63% with Angio) in D, 77% with EUS (58% with US, 42% with CT, 73% with Angio) in Rp, and 65% with EUS (58% with US, 38% with CT) in N. EUS revealed high accuracy rates because EUS images of the whole pancreas, surrounding organs and major vessels were clearly visualized through the gastroduodenal walls. Also, the accuracy rates of Angio in Rp and US in N were almost the same as those of EUS in Rp and N. However, it was difficult for every procedure to diagnose the retroperitoneal perineural invasion. From these results, EUS is one of the most beneficial procedures for detecting of the extent of cancer. EUS is expected to be popularized in the diagnosis and staging of the pancreatic cancer.

Adult↗

PubMed1991

[A case of cardiomyopathy due to allergic bronchopulmonary aspergillosis].

We report a rare occurrence of cardiomyopathy associated with allergic bronchopulmonary aspergillosis (ABPA). A 49-year-old man with a history of bronchial asthma was referred to the Matsuyama Red Cross Hospital for evaluation of the abnormal shadow on his chest X-ray. Laboratory examination showed blood eosinophilia and marked elevation of serum IgE concentration and IgE antibody to A fumigatus. The immediate and late skin reactivities to A fumigatus antigen were both positive. The diagnosis of ABPA was made. Treatment using prednisolone was effective in ameliorating the symptoms. However, he was admitted again due to dyspnea, edema and anorexia 6 months later. Chest X-ray, ECG, UCG and scintigraphy suggested severe cardiac failure. The clinical diagnosis of hypertrophic cardiomyopathy, and the pathohistological diagnosis of endomyocardial fibrosis were made by cardiac catheterization and biopsy of endocardium. Retrospectively, cardiomegaly had gradually increased during the past several months while peripheral blood eosinophilia had continued. All these data strongly suggested that eosinophilia due to ABPA might cause severe cardiac damage.

Aspergillosis, Allergic Bronchopulmonary↗

PubMed1991

[Prevalence of K-ras gene mutations in human colorectal cancers].

It has been reported that mutations in the human ras gene family convert these genes into active oncogenes. In the present study using in vitro gene amplification by the polymerase chain reaction (PCR) and mutation detection by the oligonucleotide hybridization assay, a total of 86 colorectal cancers were analyzed for the point mutations at codon 12 and 13 of K-ras genes. Mutations were present in 33 of the 86 colorectal cancers examined; 32 of the 33 mutations were at codon 12 of this gene and one of them was at codon 13. There was no apparent correlation between the presence of a ras gene mutation in a carcinoma and its anatomical location, level of differentiation, depth of invasion, degree of lymphnode metastasis or stage of progression, however, the high incidence of K-ras mutations was observed in early stage carcinomas (depth m and sm). This results support the concept that the point mutation of K-ras gene is early event in tumorigenesis of colorectal cancer.

Base Sequence↗

PubMed1990

Characterization of new human pancreatic cancer cell lines which propagate in a protein-free chemically defined medium.

Many human cancer cell lines which have been maintained in fetal bovine serum (FBS)-supplemented medium produce and secrete many substances such as transferrin, alpha 1-antitrypsin, alpha 2-macroglobulin, alkaline phosphatase, gamma-glutamyltranspeptidase, creatine kinase, carcinoembryonic antigen, alpha-fetoprotein, carbohydrate antigen 19/9, and cytokines including colony-stimulating factors and transforming growth factor, and further they may produce small amounts of unknown substances. Usually, small amounts of substances have to be concentrated as highly as possible for detection, but FBS interferes with this procedure. A protein-free culture system is an ideal method for detecting small quantities of substances which originate from cancer cells without interference by FBS. However, we were concerned that protein-free culture may interrupt the production of the substances which have been produced in FBS-supplemented medium. In this study, we investigated the productibility of 46 kinds of well-known substances in ten newly established cell lines derived from human pancreatic cancer. These cell lines were propagated in a protein-free non-FBS-supplemented medium. Of the ten cases, one cell line alone that was derived from acinal cell carcinoma propagated as a semisuspension; on the other hand, nine cell lines that were derived from ductal cell carcinoma propagated as monolayers without piling up. This method prolongs the doubling time, which is not affected by the addition of FBS. The spent media of these cell lines were collected aseptically after the removal of cell debris and concentrated by ultrafiltration using a Pericon cassette followed by lyophilization. Using 46 kinds of available antibodies, we investigated whether or not the substances which react to these antibodies could be detected in the spent media and in the cells by enzyme-linked immunosorbent assay, Western blot analysis, and immunocytochemistry. Among these cell lines, HPC-Y11 produced and secreted the most kinds of substances, and the production of those substances was lowest in HPC-Y0. In conclusion, our protein-free culture system can be available in every laboratory, since this is not only an economical method, but also an effective method for the saving of purification procedures. Moreover, this is a most suitable method for surveying unknown substances derived from cancer cell lines.

Antibodies↗

PubMed1990

Alteration in the sarcolemmal Na(+)-K+ pump of hindquarters resistance arteries in DOCA-salt rats.

It has been suggested that a circulating inhibitor of the Na(+)-K+ pump contributes to the development and maintenance of DOCA-salt hypertension. However, the discordant results have been reported as to whether the sarcolemmal Na(+)-K+ pump in DOCA-salt hypertension is inhibited. Furthermore, no study has examined alteration in the sarcolemmal Na(+)-K+ pump of the true resistance arteries. We examined hindquarters vasoconstriction induced by ouabain (10(-3) M) in the vascularly isolated hindquarters of the DOCA-salt treated or control rats, which were perfused with Krebs-Henseleit solution. Hindquarters vasoconstriction induced by ouabain (10(-3) M) was greater in the prehypertensive and hypertensive DOCA-salt rats than in the corresponding control rats (p less than 0.01). We also examined hindquarters vasoconstriction induced by ouabain (10(-3) M) in the vascularly isolated hindquarters of the normal assay rats which were perfused by the plasma obtained from the DOCA-salt or control rats. The plasma of the prehypertensive and hypertensive DOCA-salt rats attenuated ouabain-induced hindquarters vasoconstriction in the assay rats (p less than 0.01). The plasma of the DOCA-salt rats did not alter nonspecific vasoconstriction caused by barium chloride. These results suggest that the plasma of the prehypertensive and hypertensive DOCA-salt rats had an inhibitor of the sarcolemmal Na(+)-K+ pump of the resistance arteries, but the sarcolemmal Na(+)-K+ pump molecules of the resistance arteries of those rats were increased. The in vivo activity of the sarcolemmal pump of the resistance arteries of the DOCA-salt rats would be determined by the relative influence of increased pump molecules and a circulating pump inhibitor.

Animals↗

PubMed1990

[The expression of ras p21 product in hepatocellular carcinoma].

To elucidate the cell biological significance of ras oncogene, the expression of ras-p21 was analyzed in 53 cases of liver tissues including 34 cases of hepatocellular carcinoma (HCC), by using immunohistochemical method. In result, 22 (65%) cases of 34 HCC and 34 (79%) cases of 43 liver cirrhosis were positive for p21, whereas all of chronic hepatitis and normal livers were negative. Especially, comparative study between the expression of p21 and clinicopathological background of HCC revealed that p21 was prominently expressed in well differentiated form, nodular type, small liver cancer, and the cases showing AFP levels below 400 ng/ml. From these results, it was indicated that ras oncogene might play an important role in malignant transformation of hepatocytes or differentiation of HCC.

Carcinoma, Hepatocellular↗

PubMed1990

[A case of stunned myocardium determined by nuclear cardiac imaging].

A 75 year old woman with acute chest pain was diagnosed as unstable angina. Anterior akinesis of left ventricule and small anterior perfusion defect were found by 99mTc blood pool imaging and 201Tl myocardial imaging. Coronary arteriography showed no organic stenosis, though anterior akinesis was still continued. Furthermore this akinesis and perfusion defect by 201Tl were all disappeared two weeks later. Thus, we determined this case as a stunned myocardium followed by severe angina with transient coronary obstruction.

Aged↗

PubMed1990

[Chronic gastritic changes induced in rats after pyloromyotomy and per os administration of acetic acid-glycerin].

We have experimentally studied whether or not repeated episodes of acute gastric mucosal lesions can induce chronic gastritic changes. Rats received pyloromyotomy and repeated per os administration of acetic acid-glycerin. Gastric mucosal lesions thus induced were studied histopathologically in cardiac glandular areas using morphometric analysis. It was found that pyloromyotomy induced fibrosis between the bottom of the gland and muscularis mucosa. On the other hand, the per os administration of acetic acid-glycerin induced hyperplastic change of mucous neck cells. They were increased in number and in size. Distribution of mucous neck cells were distended vertically to the mucosal surface and towards the bottom of the gland. Greater the amount of acetic acid-glycerin administration, stronger the changes of mucous neck cells, i.e., the distended zone of mucous neck cells spread more and more from the cardiac area. Parietal and chief cells were decreased in number in the course of the mucous neck cell hyperplasia. Branching of glands was occasionally seen in rats receiving greater amount of acetic acid-glycerin. It was concluded that there are basic structural similarity between the gastric mucosal changes induced by repeated episodes of acute gastric mucosal lesions and the change seen in human chronic gastritis. Thus acute gastric mucosal lesions can be one of the cause of chronic gastritis.

Acetates↗