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Biomedical subjects

I Watanabe

Publications and source records attributed to I Watanabe.

At least 631 records · Page 35Linked to original sources

Virus-cell interaction in oligodendroglia, astroglia and phagocyte in progressive multifocal leukoencephalopathy. An electron microscopic study.

A 46-year-old female, with an 11 year history of malignant lymphoreticular disease, developed a neurological illness clinically manifested by a focal mass lesion in the left frontal lobe. In biopsied tissue, immunofluorescence study revealed the presence of JC antigen in the glial cells. Histologically, the lesion was characteristic of PML consisting of PML consisting of focal necrosis in the subcortical white matter, numerous fat laden macrophages and marked hypertrophy of oligodendrocytes and astrocytes. By electron microscopy, hypertrophic astrocytes contained intranuclear viral particles consistent with papova virions and aggregates of intracytoplasmic viral particles consisting of a single to several virions tightly surrounded by a single membrane. The membrane appeared to have been derived from that of the cellular vesicles. Fusion of the virus-associated membrane to the astroglial plasmalemma occurred when the virions appeared to shift towards extracellular space. The virioncontaining astrocytes showed cytoplasmic "fibrillar hypertrophy" similar to the characteristic gigantic astroglias of PML. This fact would provide an additional evidence that these gigantic cells, although lacking identifiable viral structures, were the result of anaplastic transformation by JC virus. Many virus-bearing astroglias were noted to be in the early stage of cellular necrosis, of "edematous degeneration". This further indicates that the JC virus is capable of inducing both lytic and abortive astroglial infections. Many oligodendroglias were hypertrophic due to the presence of intranuclear viral particles and markedly increased numbers of microtubules and free ribosomes in the cytoplasm. Membrane-bound intracytoplasmic viral particles were also noted in the oligodendroglias. Some fat laden macrophages contained large intracytoplasmic viral bodies, presumably originating from phagocytized virus-bearing cells.

Astrocytes↗

Vacuolation of oligodendroglia in neoplastic perifocal edema.

Vacuolation of oligodendroglia, a new type of cytopathological change, has been described. The change is observed frequently at the perifocally edematous cerebral white matter adjacent to the metastatic lesions of carcinoma from the lung in all three cases examined. It is also present occasionally in association with astrocytoma. This condition is characterized by swelling of oligodendroglias due to numerous cytoplasmic vacuolations which contain the material identical with that of the extracellular edema fluid. In such cells, the nucleus is displaced and deformed by vacuoles but the nuclear chromatin and envelopes are arranged normally. By occupation of numerous large vacuoles the cytoplasm is divided into small areas, but the individual organelles are only minimally altered. The oligodendroglial vacuolation seems to be a phagocytic response to the edema fluid which contains proteinous macromolecules derived from blood-borne protein and necrotic material of brain tissue and neoplastic cells. The vacuolation may result in some oligodendroglial dysfunction in maintenance of myelin and probably be related with diffuse loss of myelin sheath in the longstanding brain edema secondary to neoplastic invasion. The vacuolated cells can be identified with light and electron microscopes in Epon-embedded sections of surgically removed tissue but not in paraffin sections.

Aged↗

Gold nephropathy. Ultrastructural, fluorescence, and microanalytic studies of two patients.

Renal biopsy specimens from two patients with gold nephropathy showed two distinctly different types of alterations. The first demonstrated lesions suggestive of immunologic injury primarily to the glomerulus and identical with membranous glomerulonephritis. The second had no evidence of immunologic injury, but contained extensive vacuolar degeneration of proximal tubular epithelial cells. Ultrastructurally, the vacuoles contained lipid materials and occupied the basal portion of the cells. Other tubular cells contained numerous "gold-containing" cytosegresomes. In this second specimen, it appeared that the filtered gold had a direct toxic effect on the tubular epithelium and perhaps also on the glomerular capillary wall. These findings suggest that gold nephropathy may indeed be a spectrum of a combination of both direct toxic and immunologic injury to glomeruli and tubules.

Aurothioglucose↗

Follow-up studies of long term survivors after hepatic portoenterostomy for "noncorrectible" biliary atresia.

Fourteen patients with "noncorrectable" biliary atresia are living without jaundice for more than 2 yr after hepatic portoenterostomy or its modification. Retardation of physical growth was observed in one of them, and mental retardation in another, both of which seemed irrelevant to biliary atresia. Serial tests for liver function after operation revealed early recovery of serum bilirubin, transminase, and turbidity, and delayed improvement of alkaline phosphatase. Postoperative needle biopsy of the liver disclosed that changes in hepatic parenchyma and ductular proliferation were rapidly improved after successful operation. Improvement of fibrosis of the liver was delayed, and it was not satisfactory in patients whose preoperative changes in the liver were severe or in whom ascending cholangitis had been a frequent complication. Histologic features of hepatic cirrhosis were observed in the liver in three cases, in two of which there had been frequent episodes of cholangitis. Only one of these showed clinical signs of portal hypertension. Functional and morphologic cure can be achieved in "noncorrectable" biliary atresia by hepatic portoenterostomy or its modifications, although varying degree of hepatic fibrosis may remain according to severity of preoperative changes of the liver and postoperative complication of ascending cholangitis.

Adolescent↗

Pseudomyxoma peritonei: report of an unusual case.

Pseudomyxoma peritonei, a rare disease, is characterized by accumulation of mucinous material in the peritoneal cavity and is commonly caused by ovarian tumors or appendicular lesions. This report presents necropsy findings of an unusual case of pseudomyxoma peritonei caused by dissemination of mucinous adenocarcinoma of the stomach, hitherto unreported in literature.

Cystadenoma↗

Comparison of the cardiac output measurements with electromagnetic flowmeter and dye-dilution technique in dogs, with a note on the comparison between radiocardiography and ear-dye method in man.

There are relatively few studies and opinions are still divided as to the agreement between the electromagnetic flowmeter and dye-dilution technique in measurements of cardiac output in animals. Of 22 pairs of cardiac output measurements performed with an electromagnetic flow probe applied to the root of aorta in open-chest, anesthetized dogs and with peripheral venous injection of indocyanine green dye and an arterial cuvette, the measured points fell within the range of plus or minus 20% on both sides of the line of identity in 19 instances. Studied on 8 human subjects with radiocardiography and ear-dye method performed simultaneously with peripheral venous injection of a mixture of R131ISA and indocyanine green, cardiac output given by ear-dye method was higher than that given by radiocardiography by an average of 9 plus or minus 11 (SD)%. Agreement and disagreement in cardiac output measurements given by electromagnetic flow probe, dye-dilution method with arterial cuvette, dye-dilution method with ear-piece densitometer and radiocardiography were discussed.

Animals↗

The mean circulatory pressure, reproducibility of its measurements and the effect of phenylephrine with a note on the effect of pentobarbital.

With 7 repeated measurements of the mean circulatory pressure (MCP) over a course of 35 minutes in one and the same dog, and also with paired measurements of MCP 10 minutes apart in 6 other dogs, the MCP was shown to be stable and reproducible in anesthetized, open-chest and vagus-intact dogs. Administered to 7 dogs with initial mean arterial blood pressure as low as 64 mmHg in dose of 20 mug/kg intravenously, phenylephrine nearly doubled the mean arterial blood pressure, total peripheral resistance and the MCP, indicating a marked vasoconstrictor effect on the resistance and capacitance blood vessels of the systemic circulation. The effect was transient and there were signs of tachyphylaxis. Influence of a cardiotoxic dose of pentobarbital on the peripheal circulation was discussed.

Animals↗