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Biomedical subjects

T Kanda

Publications and source records attributed to T Kanda.

At least 613 records · Page 34Linked to original sources
PubMed1982

Distal myopathy: histochemical and ultrastructural studies.

In three familial cases and one sporadic case of late-onset distal myopathy, muscle wasting started in the distal portions of the lower extremities. The most striking change seen by light microscopy was the appearance of rimmed vacuoles. These were presumed to be autophagic, because they were found by electron microscopy to contain membranous lamellar structures and other heterogenous materials enclosed by a limiting membrane. On the other hand, lysosomal activity was markedly increased in skeletal muscle. In 6% to 22% of affected muscle fibers there were acid phosphatase-positive granules deep in the sarcoplasm, whereas control muscles had no such granules. The degenerative process in distal myopathy may be different from that in other muscular dystrophies.

Acid Phosphatase↗
PubMed1982

Restricted viral RNA synthesis in establishment of persistent infection in Vero cells with a Sendai virus mutant.

It was previously shown that a temperature-sensitive mutant of Sendai virus, ts-23, readily establishes persistent infection in Vero cells at 37 C, a permissive temperature for growth of the mutant. In the present study, it was demonstrated that the virus yield from ts-23-infected Vero cells at 37 C began to decrease 48 to 72 hr postinfection, after an initial phase of high virus production. Before the decrease in virus production, the formation of viral nucleoprotein declined, although synthesis of all species of viral protein continued. It was suggested that the limited formation of viral nucleoprotein and the decrease in virus production were due to the restriction of viral RNA synthesis which began to occur early after infection in ts-23-infected cells at 37 C. The mutant has a temperature-sensitive defect in RNA polymerase activity and the temperature 37 C, used for establishment of persistent infection, would be a semi-permissive temperature for the RNA polymerase activity of the mutant. The ts-23 mutant interfered with the replication of the parental wild virus in Vero cells at 37 C.

Animals↗
PubMed1982

Experimental parainfluenzavirus infection in mice: fatal illness with atrophy of thymus and spleen in mice caused by a variant of parainfluenza 3 virus.

Intracerebral inoculation of the YN strain of parainfluenza 3 virus was found to induce an acute fatal illness characterized by marked thymic and splenic atrophy in newborn mice. Previously we showed that the YN strain contains three distinct plaque-type variants, LT, SC, and M. Of these, the M-type variant induced this fatal illness, whereas the other two variants induced hydrocephalus.

Animals↗
PubMed1981

Parainfluenza 3 virus: plaque-type variants lacking neuraminidase activity.

Virus clones lacking detectable neuraminidase activity (SC-YN and M-YN) as well as those possessing it (LT-910N and LT-YN) were isolated from bovine strains of parainfluenza 3 virus. LT-910N and LT-YN viruses produced large turbid plaques in MDBK cells, and SC-YN virus produced small clear plaques. Incorporation of a bacterial neuraminidase in agar overlay medium made SC-YN virus form large turbid plaques, whereas it made M-YN virus form large clear plaques. However, M-YN virus formed only pinhole plaques or no plaques in the absence of neuraminidase. The exogenous neuraminidase had little effect on the plaque formation of LT-910N and LT-YN viruses. M-YN virus induced extensive syncytial formation, and SC-YN virus produced less extensive syncytial formation. The exogenous neuraminidase enhanced replication of SC-YN and M-YN viruses and reduced syncytial formation by these viruses. The enzyme had little effect on replication and cytopathic effect of LT-910N and LT-YN viruses. The reason for these effects of the exogenous neuraminidase is discussed.

Animals↗
PubMed1980

Purification and properties of a lower-molecular-weight endo-cellulase from Irpex lacteus (Polyporus tulipiferae).

A new endo-cellulase component of carboxymethyl cellulase (CMCase) type (En-1) was obtained by gel filtration and column chromatography from Driselase, a commerical enzyme preparation from Irpex lacteus (Polyporus tulipiferae). The enzyme behaved as a single protein on polyacrylamide disc electrophoresis in the presence of sodium dodecyl sulfate (SDS). Its molecular weight was estimated to be 15,500 and it contained only 0.73% carbohydrate as glucose. The pattern of its amino acid composition is similar to those of other cellulases in respect of high contents of acidic amino acids, glycine, serine, and threonine. The cellulase was most active at pH 4.0 and was very stable in the pH range of 3.0 to 6.0, but was completely inactivated by heating at 70 degrees C for 10 min. A series of cellooligosacharides, including cellobiose, was formed by this enzyme from sodium carboxymethyl cellulose (CMC) as well as from water-insoluble celluloses. In the hydrolysis of CMC, the increase in the fluidity of the substrate was relatively large as compared with the simultaneous increase in reducing power. From this result and the pattern of hydrolysis products, En-1 was elucidated to be an endo-cellulase, and it showed the highest randomness among the cellulase components obtained so far from Irpex lacteus.

Amino Acids↗
PubMed1980

Modes of action of exo- and endo-cellulases in the degradation of celluloses I and II.

Cotton and Valonia-cellulose (cellulose I) were readily attacked by endo-cellulase of a highly endowise-hydrolysis type, with a sharp decrease in the degree of polymerization, while the simultaneous production of reducing sugar was low. In contrast, viscose rayon and alkali-cellulose (cellulose II) showed little lowering of the degree of polymerization by endo-cellulase, though the effect was slightly greater than with an exo-cellulase, while the simultaneous production of reducing sugar was very high. The synergistic effect of exo- and endo-cellulases on the hydrolysis of cellulose was much higher with cellulose I than with cellulose II. These results can be explained in terms of differences in the polarity of cellulose chains and in the crystallinity and/or ultrastructure of the cellulose fibers.

Cellulase↗
PubMed1980

Isolation and characterization of temperature-sensitive mutants of Sendai virus.

Sixteen temperature-sensitive mutants of Sendai virus were isolated from mutagenized stocks (10 mutants, designated numerically) and persistently infected cultures (6 mutants, designated alphabetically). Based on complementation tests, virion-associated activities, thermal inactivation, and viral RNA and hemadsorbing antigen synthesis as well as virion production in chick lung embryo cells at nonpermissive temperature, these mutants were divided into seven groups as follows. i) HANA group mutants (ts-5, -9, -10, -201), defective in hemagglutinin-neuraminidase protein, complementation group I. ii) F group mutants (ts-18, -108), defective in hemolytic and cell-fusing activity, complementation group II. iii) Ts-43, defective in RNA polymerase activity, complementation group III. iv) Ts-23, defective in RNA polymerase activity, interfered with the other mutants in complementation tests. v) Ts-25, defective in the incorporation of hemagglutinin-neuraminidase protein into the virion at the stage of virus assembly. vi) Ts-110, belongs to F group mutants on one hand, but is considered to carry another undetermined defect. vii) C group (carrier culture-borne group) mutants (ts-a, -b, -c, -d, -e, -f), defective lesion not yet determined and belong to neither complementation group I nor II. Assignment of mutants in groups iv), v), vi), and vii) to complementation groups could not be achieved.

Cell Line↗
PubMed1980

Is normoreninemic essential hypertension caused by disordered central dopaminergic regulation?

Some investigators have reported that plasma prolactin levels are elevated in hypertensive men and that both their hyperprolactinemia and hypertension were controlled by bromocriptine, a dopamine agonist. They concluded that reduced central dopaminergic activity may be a factor in maintaining essential hypertension. We examined the serum prolactin and thyrotropin (TSH) responses to thyrotropin releasing hormone (TRH), metoclopramide (a dopamine antagonist) and bromocriptine in 10 normal and 10 hypertensive normoreninemic men. TRH caused significant increase of both prolactin and TSH and metoclopramide caused significant increase of prolactin in both normals and hypertensives. Bromocriptine suppressed prolactin and TSH significantly in both groups. There were no significant differences in prolactin and TSH levels between the normal and hypertensive groups before or during the tests. These results provide no support for the hypothesis that alterations in the activity of central dopaminergic neurons are involved in the maintenance of the elevated blood pressure of normoreninemic men with essential hypertension.

Bromocriptine↗