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T Kasuga

Publications and source records attributed to T Kasuga.

At least 127 records · Page 7Linked to original sources
PubMed1986

Histogenesis of the intradermal melanocytic tumor in BDF1 mice induced by topical application of 9,10-dimethyl-1,2-benzanthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA).

The histogenesis of the intradermal melanocytic tumor induced in the skin of 88 female BDF1 mice by DMBA and TPA is studied light-and electron-microscopically. Four types of melanocytes were found in the mouse skin. The epidermal melanocytes transiently appeared several days after topical application of DMBA. Hair follicles turned into anagen phase and follicular melanocytes became apparent by week 3. After week 3, intradermal melanocytes of the perifollicular melanocytic networks (PFM), which were scattered in untreated mouse skin, proliferated to form the intradermal melanocytic tumors, and 267 tumors, composed of oval melanocytes in medullary growth, were induced in all of the 19 treated mice by week 32. Large dendritic melanocytes located deep in the reticular dermis, which did not participate in the formation of the tumor. Only 3 papillomas were induced in 2 of the 19. Light-and electron-microscopically, there was no evidence of migration of epidermal and hair follicular melanocytes into the dermis. Additionally, melanin-producing activity in the cytoplasm of Schwann cell and perineural epithelium was observed. The histogenesis of the intradermal melanocytic tumor was closely related to the melanocytes of the perifollicular melanocytic network (PFM).

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1986

Dynamics of lymphocytic subpopulations in Friend leukemia virus-induced leukemia.

The in vivo roles of the immunosurveillance mechanism of the host against leukemia induced by Friend leukemia virus (FLV) were examined. The significance of T-cells in host defense against FLV-induced leukemia was indicated by the fact that thymus-deprived C57BL/6N-nu/nu mice were sensitive to FLV, although normal C57BL/6N mice were, as already reported by many authors, resistant to FLV. In relation to the role of T-cells on the onset of FLV-induced leukemia, the population dynamics of the lymphocytic subpopulations of the systemic lymphoid organs after FLV injection in FLV-resistant C57BL/6N mice were examined in comparison with the dynamics in FLV-sensitive strains, C57BL/6N-nu/nu mice and normal C3H/HeN mice. In this system, Lyt-1+2- helper T-cells in the spleen of FLV-resistant C57BL/6N mice increased in number after FLV injection. The number of immunoglobulin positive cells did not remarkably change in FLV-resistant C57BL/6N mice after FLV injection, whereas the number increased in the lymph node of FLV-sensitive C3H/HeN mice. The results indicated that a major contribution to the relative susceptibility and resistance of the host to FLV was controlled by the capacity to mobilize T-cells to the spleen in an early stage of disease, although the interaction of these T-cells with other immune cells may play an important role in mediating host resistance to FLV-induced disease.

Animals↗
PubMed1986

Effects of Friend leukemia virus (FLV) inoculation in F1 mice and differentiation of FLV-induced leukemia.

Effects of Friend leukemia virus (FLV) inoculation in F1 specific pathogen free (SPF) mice were examined. Resistance to FLV was dominantly inherited both in F1 hybrid mice (BDF1) (FLV-resistant & FLV-sensitive with polycythemia) and F1 hybrid mice (B6C3F1) (FLV-resistant & FLV-sensitive with anemia). But the population dynamics of the nucleated cell components of F1 mice after FLV inoculation differed from those of FLV-resistant inbred mice. A small number of mature erythroblasts appeared in the peripheral blood of BDF1 mice. In B6C3F1 mice, erythroblastosis with splenomegaly and polycythemia occurred. However, all of these findings in BDF1 and B6C3F1 mice regressed spontaneously. In F1 mice, FLV induced an intermediate reactive pattern of the two patterns that had been induced in the parental strains. The results indicate that FLV may induce leukemia with various degrees of differentiation, according to the genetic difference of the host.

Animals↗
PubMed1985

Neoplastic angioendotheliosis. Immunohistochemical and electron microscopic findings in three cases.

Three cases of neoplastic angioendotheliosis (NAE) presenting with central nervous system (CNS) disease but no skin lesions are described. The histogenesis of the neoplastic cells is discussed. Microscopic examination showed accumulation of neoplastic cells in the vascular system throughout the body and their extravascular proliferation in several organs. Electron microscopic and immunohistochemical studies revealed the presence of Weibel-Palade bodies and factor VIII-related antigen in intravascular and extravascular neoplastic cells in two of the three cases. In the first case the neoplastic cells did not have any T-cell markers. However, in one case no specific markers were found in the neoplastic cells by electron microscopic, enzyme histochemical, or immunohistochemical examination. These findings, although supporting the endothelial origin of the neoplastic cells, indicate the need for further consideration of whether NAE is actually a single disease entity or several different diseases.

Aged↗
PubMed1985

Malignant mixed mesodermal tumor of bladder occurring after radiotherapy for cervical cancer: report of a case.

A rare case of radiation-induced malignant mixed mesodermal tumor of the bladder is reported. A 78-year-old woman complained of hematuria, which originated from a polypoid tumor in the bladder 15 years after radiotherapy for squamous cell carcinoma of the uterine cervix. The bladder tumor recurred 9 months after resection and partial cystectomy then was performed. Histological findings revealed malignant mixed mesodermal tumor composed of carcinomatous and sarcomatous elements. The former element consisted mainly of transitional cell carcinoma with occasional foci of squamous metaplasia and glandular differentiation, while the latter consisted of spindle cell sarcoma showing partly cartilaginous and osseous differentiation. The histogenesis of malignant mixed mesodermal tumor of the bladder also is discussed.

Aged↗
PubMed1985

[Malignant schwannoma arising in Recklinghausen's disease--report of 4 cases].

Four cases of malignant schwannoma arising in Recklinghausen's disease are described. The 4 patients, aged 38, 41, 44 and 38, 2 men and 2 women, had up to child-head-sized tumors in the neck, back, axilla and retroperitoneum. Oncostatic chemotherapy and irradiation were ineffective against the malignant schwannoma. In three, surgically tumor-resected cases, local recurrence and rapid tumor growth occurred. Histologically, malignant schwannoma was characterized by the presence of a few collagen fibers among the tumor cells, but abundant argentaffin fibers. Numerous mast cells are frequently seen in neurofibroma, but almost never in malignant schwannoma. In Case 3, with mild atypism, tumor cells were positive for S100 protein.

Adult↗
PubMed1985

[Ganglioneuromatosis with carcinoid foci in the large bowel].

A rare case of a 27-year-old man who suffered from ganglioneuromatosis with five carcinoid foci arising from the colon and underwent subtotal colectomy is reported. There was no malignancy. The tumors extended to the mucosa and/or submucosa, and in most parts, tumors created polypoid lesions protruding into the intestinal lumen. In the rectum the tumors showed circumscribed extension around the wall. In the sigmoid and descending colon, polypoid lesions were seen on the side opposite from the attachment line of the mesocolon. In one of five carcinoid foci, a transitional pattern between carcinoid and neuroma was investigated.

Adult↗
PubMed1984

Histometrical investigation of the pulmonary artery in severe hepatic disease.

Histological changes of the pulmonary vasculature in comparison with that of the portal vein in necropsy cases of severe hepatic injury that had not been associated with clinical pulmonary hypertension were analysed qualitatively and quantitatively. The main changes of the intra-hepatic portal vein were dilatation (88.3 per cent), thickening of the wall (58.5 per cent) and thrombi (22.3 per cent). The changes of the pulmonary vasculature were limited to muscular type arteries, which showed dilatation (31.9 per cent), thickening of the wall (30.9 per cent) and thrombi (10.6 per cent). Association of wall thickening of the portal vein and the small pulmonary artery was observed in 30.9 per cent, these associations being statistically significant. Coincidence of thrombus formation in the portal vein and pulmonary vasculature was observed only in 4.3 per cent, which was not statistically significant. After the circumferences of the internal and external elastic laminae of small pulmonary arteries and the cross-sectional area of the media were measured, the anatomical radius and wall thickness of each artery were calculated according to Furuyama 's method. The relations between the anatomical radii and wall thickness of small pulmonary arteries in controls and hepatic cirrhosis groups were investigated by analysis of covariance to compare the equality of the two corresponding regression lines. The wall thickness and the ratio of wall thickness to the anatomical radius of small pulmonary arteries were significantly larger in the cirrhotic group than in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1984

Progressive multifocal leukoencephalopathy associated with prolonged hemodialysis treatment.

The association of progressive multifocal leukoencephalopathy (PML) with prolonged hemodialysis treatment (PHT), not previously reported, was observed in a 56-year-old Japanese man who received PHT for 11 years. He suffered from recurrent bouts of fever and progressive neurological signs, such as irritability, speech disturbance, gait disturbance and dysphagia for seven months, and finally fell into a deep coma and died. Clinical signs and symptoms were highly suggestive of progressive dialysis encephalopathy. Necropsy revealed that the PML mainly involved the brainstem and cerebellar white matter. The aluminium content of the brain tissue was lower than that of controls. Possibly the virus causing PML is one of the causes of progressive dialysis encephalopathy, since clinically PML is not easily distinguished from progressive dialysis encephalopathy. It is essential to differentiate PML of viral etiology from progressive dialysis encephalopathy of unknown cause.

Brain↗
PubMed1984

Idiopathic cardiomyopathy: the pathologic roles of arteriolopathy.

Structural alterations and pathologic features of arteriolopathy of the heart were studied in 12 patients with idiopathic cardiomyopathy, five with hypertrophic cardiomyopathy (HOCM), and seven with congestive cardiomyopathy (COCM). The patients, six men and six women, ranged in age from 25 to 66 years. Diagnoses of idiopathic cardiomyopathy were confirmed clinically and at autopsy. Heart weights ranged from 350 to 700 g. Dilatative hypertrophy of both ventricles was observed in four patients, dilatation of both ventricles in six patients, and concentric hypertrophy of the left ventricle in two patients. The ventricular septa ranged in thickness from 7 to 27 mm, and the septal:free wall ratios ranged form 1.0 to 1.8. The lumens of extramural coronary arteries showed less than 30 per cent narrowing. Sections of the heart and all body organs were examined. The myocardia showed microscopic areas of hypertrophy, degeneration and disorganization of muscle cells, interstitial fibrosis, and various features of arteriolopathy. Histometric studies showed that hypertrophy of muscle cells was greater in HOCM than in COCM, that the content of connective tissue in the myocardium was higher in COCM, and that interstitial fibrosis was greater in the epicardial zone than in the endocardial zone in COCM but was greater in the endocardial zone in HOCM. Of the arteriolar changes, those of smooth muscle cells and internal elastic lamina were observed most frequently; no arteriolar narrowing or stenosis was observed in either HOCM or COCM. The correlation between the frequency of arteriolopathy (loss of smooth muscle cells in the media) and myocardial interstitial fibrosis was significant in COCM (P less than 0.05) but not in HOCM. No significant correlations were found between arteriolopathy and age, the duration of symptoms, the cause of death, the heart weight, the thickness of the septum or posterior free wall, the septal:free wall ratio, the presence of disorganized cells in the septum, mural thrombi, the mean muscle cell diameter, or the extent of very hypertrophic cells (P greater than 0.05) in either HOCM or COCM.

Adult↗
PubMed1984

Cardiovascular lesion of carcinoid syndrome. An autopsy case of bronchial carcinoid.

An autopsy case of a 67-year-old Japanese male is presented. He had been suffering from carcinoid syndrome for 5 years and showed a typical picture of carcinoid heart disease. In Japan, carcinoid heart disease is rare and we can find only four reported cases (33% of reported carcinoid syndrome). The patient had high urinary secretion of 5-HIAA and high serum serotonin, and finally he died of heart failure and bronchopneumonia. The primary site of this carcinoid tumor was of the bronchus of the right B10c , and it had large hepatic metastases. Electronmicroscopically, the tumor cells had secretory granules measuring 1500-3500 A in diameter. Immunohistochemically, the tumor cells were markedly positive for human chorionic gonadotropin (hCG) and antidiuretic hormone (ADH) and positive for serotonin, in both the primary site and hepatic metastases. Characteristic fibrous plaques were detected in the right atrium, tricuspid valve, right ventricle, and left atrium. Electron-microscopically, the fibrous plaques consisted of smooth muscle cells and myofibroblasts surrounded by basement membrane-like material. The abundant matrix of the fibrous plaques contained acid mucopolysaccharide, microfibrils and collagen fibers. The same fibrous plaques were also found in hepatic veins. Furthermore, retroperitoneal fibrosis was present, which showed proliferation of myofibroblasts, fibroblasts and immature mesenchymal cells.

Aged↗
PubMed1984

Establishment of human glioblastoma multiforme cell line, G5A.

A new cell line, G5A, was established from a human glioblastoma multiforme of the primary site and maintained for 25 months, subcultivated 36 times. The cloned cells showed morphologically epithelial-like patterns and loss of glial filaments. The cells inoculated in the nude mice produced tumors in 100% of the mice. The plating efficiency of the cell line was 20.9% in a standard culture. The modal chromosome number was 63 with many morphological abnormalities. The generation time was 22.9 hours and the parameters of the cell cycle were clarified by the percent labeled mitosis analysis. No morphological differentiation of the cell line was induced by the chemical differentiation-inducers.

Adult↗
PubMed1984

[Utilization of melanin precursors for experimental chemotherapy of malignant melanoma].

Melanin synthesis is a metabolic pathway unique and specific to melanocytes. It occurs by conversion of tyrosine to dopa and dopaquinone in the presence of tyrosinase. It is highly accelerated in malignant melanoma with a marked increase of tyrosinase activity. This study summarizes the recent progress in experimental chemotherapeutic approaches to malignant melanoma by utilizing melanin precursors, and presents our current results. Our studies indicated (a) that hydroquinone and 4-isopropylcatechol are selectively toxic to melanocytes and melanoma cells, (b) that their actions are mediated through tyrosinase, and (c) that dopa is selectively and highly incorporated into melanoma cells and melanocytes depending on the tyrosinase activity. In addition, our new compounds, i.e., 4-S-cysteinylphenol and 4-S-cysteaminylphenol were highly toxic to melanoma cells, increasing the life span of B16 melanoma bearing mice and decreasing melanoma growth in C57 BL mice. Other synthetic compounds, e.g., cysteinylcatechols and their devivatives, were, however, not toxic to melanoma cells. 4-S-cysteinylphenol and 4-S-cysteaminylphenol appeared to exert their cytotoxicity through the action of tyrosinase present in melanoma cells, thus providing a kind of "guided missile" approach to melanoma chemotherapy.

Animals↗
PubMed1984

[So-called carcinosarcoma of the breast--report of 4 cases].

Four cases of so-called carcinosarcoma of the breast were studied histopathologically. The patients were females aged 44, 37, 44 and 77 who were admitted to the Cancer Institute Hospital for breast tumors. Histologically, the tumors showed proliferation of sarcomatous cells with relatively small amounts of papillotubular carcinoma or scirrhous carcinoma. There were transitions between the sarcomatous portion and carcinoma. Two cases showed squamous metaplasia merging into the sarcomatous component, whereas the other 2 showed transition from adenocarcinoma to sarcomatous element. Lymph nodal metastases in 2 cases were papillotubular carcinoma. One patient died of lung and brain metastases, and autopsy revealed only sarcomatous element.

Adult↗
PubMed1983

[Liver cell carcinoma with extensive proliferation of sarcoma-like neoplastic cells--an autopsy case].

A 73-year-old male was admitted with suspected Grawitz tumor. Aspiration cytology from the tumor was diagnosed as Class V with suspected sarcoma. He died 17 days after admission. Autopsy revealed this to be a massive hepatic tumor occupying over half of the right lobe. It showed protrusion into the right retroperitoneum. Histology of the tumor evidenced widespread proliferation of sarcoma-like neoplastic cells besides a minute area of definite liver cell carcinoma in the center of the tumor mass. Definite transitional features between liver cell carcinoma and a sarcomatous pattern, the latter involving a major part of this tumor, were noted. Thus, we diagnosed this tumor to be liver cell carcinoma with a sarcoma-like histological pattern. The possibility of collision tumor or carcinosarcoma could be ruled out.

Aged↗