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Biomedical subjects

K Kadota

Publications and source records attributed to K Kadota.

At least 145 records · Page 8Linked to original sources

Histological progression of follicular centre cell lymphomas to immunoglobulin-producing tumours in two pigs.

Follicular centre cell lymphomas in two crossbred sows were examined histologically, immunologically and ultrastructurally. In one case, most of the involved tissues showed a diffuse growth pattern and follicular structures were present in some lymph nodes. In some areas, immunoblastoid cells were scattered or focal (immunoblastic transformation) and contained only cytoplasmic IgM (CIgM) or both CIgM and cytoplasmic IgG. In the other case, the neoplastic cells grew diffusely and an incompletely affected lymph node showed separate neoplastic follicles as well as direct transition into a diffuse growth pattern, without the stage of accumulated follicles. Scattered immunoblastoid or plasmacytoid cells with CIgM were present in some sections (plasmacytic differentiation). The origin and histological progression of these neoplasms are discussed and it is suggested that the presence of two immunoglobulins in single neoplastic cells could be the result of heavy chain class switch. As these swine lymphomas resembled human lymphomas they may offer useful models for the study of the latter.

Animals↗

Isolation of Theileria sergenti piroplasms from infected erythrocytes and development of an enzyme-linked immunosorbent assay for serodiagnosis of T sergenti infections.

A method of obtaining a pure suspension of Theileria sergenti piroplasms from infected bovine erythrocytes was developed and the resulting parasites used as antigen in an enzyme-linked immunosorbent assay (ELISA). Piroplasms were freed from infected erythrocytes using the nitrogen cavitation technique and then separated from unbroken erythrocytes by centrifugation at 670 gmax. The parasites in the supernatant were then sedimented by centrifugation at 2700 gmax and the purified fraction examined by electron microscopy. This examination showed that the isolated piroplasms were morphologically intact and that there were few contaminants. SDS-PAGE and spectrophotometric analysis showed that this fraction contained little erythrocyte component. The piroplasms thus obtained were sonicated and treated with Triton X-100 then used for ELISA antigen. The ELISA values had a high correlation with titres obtained using the indirect fluorescent antibody test on sera from cattle infected with T sergenti.

Animals↗

Ultrastructure of swine myelogenous leukaemic cells, with particular reference to intracytoplasmic granules.

Seven cases of swine myeloid leukaemias were investigated by light and electron microscopy. All animals were adult sows. Morphologically these cases were classified as myeloblastic leukaemia with maturation (Cases 1 to 6) and chronic myeloid leukaemia (Case 7). The neoplastic cells were composed of immature promyelocytoid cells in Case 1. In Cases 2, 3, 4 and 5 there were immature or mature promyelocytoid cells containing peroxidase-positive granules. In Case 6, the neoplastic cells consisted of promyelocytoid cells and myelocytoid cells. The latter predominated and contained not only peroxidase-positive granules but also peroxidase-negative ones. The neoplastic cells in Case 7 showed various stages of cell maturation. The morphological characteristics in our cases resembled those in human myeloid leukaemias.

Animals↗

Detection and evaluation of tricuspid regurgitation using a real-time, two-dimensional, color-coded, Doppler flow imaging system: comparison with contrast two-dimensional echocardiography and right ventriculography.

To detect and evaluate regurgitant flow in tricuspid regurgitation (TR) with a newly developed, realtime, 2-dimensional (2-D), color-coded, Doppler flow imaging system (Doppler 2-D echo), 27 patients (18 with suspected TR and 9 normal subjects) were examined and the findings were compared with those obtained using contrast 2-D echocardiography (contrast 2-D echo) and right ventriculography. In 16 of 18 patients with suspected TR, Doppler 2-D echo easily visualized the color-coded regurgitant flow in the right atrium and estimated the severity of TR from the distance of the visible TR jet. On the basis of the QRS synchronized appearance of contrast in the inferior vena cava by the subxiphoid approach or of the negative contrast effect above the tricuspid valve just after the contrast entered the right ventricle with its subsequent back-and-forth movements across the tricuspid valve, Doppler 2-D echo was more sensitive and specific in detecting TR (100% and 100%) than contrast 2-D echo (75% and 82% in the subxiphoid view, 56% and 100% in the 4-chamber view) when the fast Fourier transformation frequency analysis was used as the standard of TR, and it was more sensitive in detecting TR (85%) than contrast 2-D echo (69% in the subxiphoid approach, 46% in the 4-chamber view) when right ventriculography was used as the standard of TR. Additionally, the severity of TR as shown by Doppler 2-D echo correlated fairly well with that shown by right ventriculography. Thus, Doppler 2-D echo is clinically useful for detecting and evaluating TR.

Adult↗

Immunological and ultrastructural observations on swine thymic lymphoma.

A case of swine thymic lymphoma is described. A young pig had a mediastinal mass and bone marrow involvement and the microscopic findings showed peripheral blood involvement. The tumour was composed of small to medium sized lymphoid cells which formed rosettes with sheep erythrocytes and were characterized by narrow cytoplasmic bands, nuclear convolution and clustered dense bodies. Such structural and immunological features resembled those of human thymic lymphomas derived from thymic T-cells.

Animals↗

Ultrastructure and origin of adenocarcinomas detected in the lungs of three cows.

Three types of bovine adenocarcinoma were found in the lungs of 3 cows. Case 1 was a well differentiated adenocarcinoma with mucin granules and microvilli with core filaments seen ultrastructurally. In Case 2, the neoplastic tissue showed a sarcoma-like growth with scattered tubular structures. Many cilia were observed in the tubular structures and a few cilia were found in the anaplastic tissues. Case 3 had epithelial and undifferentiated tissues. A few mucin granules and cilia were observed in the tumours in both lung and kidney. The relationships between these neoplastic cells and bronchial epithelial cells are discussed.

Adenocarcinoma↗

Three types of swine immunoglobulin-producing tumours: lymphoplasmacytic lymphosarcoma, immunoblastic lymphosarcoma and plasmacytoma.

Three types of swine immunoglobulin-producing tumours are described. Case 1 was a lymphoplasmacytic lymphosarcoma, in which IgG was intracellularly identified in the plasmacytoid cells. Case 2 was an immunoblastic lymphosarcoma, the large cells of which possessed intracytoplasmic IgG and well developed RER. Case 3 was diagnosed as a plasmacytoma. There were two distinct immunoglobulins, IgG and IgA, in single plasmacytoid cells and the RER was highly developed. The origins of the three cases are discussed according to the theory of B-lymphocyte differentiation sequences and the origins of B-cell lymphomas. The mechanism of "double producers" is discussed with reference to DNA and RNA.

Animals↗

Quantification of thallium-201 myocardial uptake using serial dynamic imaging at rest and during exercise.

The thallium-201 myocardial uptake ratio was measured using serial dynamic imaging of the initial uptake phase following an intravenous bolus injection. It revealed no significant difference at rest between non-coronary heart disease and coronary artery disease, while it was greater in cases with left ventricular hypertrophy. With exercise loading, this value significantly increased in non-coronary heart disease, whereas less increase was observed in coronary artery disease. This increasing capability was lower in multivessel disease compared with single-vessel disease.

Adult↗

[Intracoronary thrombolysis for high risk patients with acute myocardial infarction].

Fifty-four patients with acute myocardial infarction (AMI) were treated by percutaneous transluminal coronary recanalization (PTCR) within six hours after onset of symptoms or at the time of emergency coronary angiography. Of these, six patients had neither good collaterals nor recanalization, and followed by mechanical failure due to rupture of the left ventricular free wall or interventricular septum in five patients despite antihypertensive therapy. In the remaining 48 patients with good collaterals or recanalization, mechanical failure was statistically infrequent and occurred in only two patients (p less than 0.001). Ninety-four patients treated by PTCR were assessed in terms of mortality, cause of death and their hemodynamic findings. Cardiac deaths occurred in nine patients (9.6%); mechanical failure, in four; and cardiogenic shock due to the occlusion of the left main trunk, in five. Cardiac death was more frequently encountered in the era of the initial stage of PTCR (six of 53 cases: 11.3%) and the main cause was mechanical failure (four of six cases). On the other hand, cardiac death in recent years of PTCR was less (three of 41 cases: 7.3%), and all three had pump failure due to the occlusion of the left main trunk. Risk of mechanical failure was successfully resolved using intra-aortic balloon pumping and beta-blocker in addition to antihypertensive therapy. At the present time, PTCR and other supplementary therapy mentioned above reduced the mortality from mechanical failure and cardiogenic shock, but occlusion of the left main trunk remains an important cause of death in patients with AMI.

Aged↗