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Biomedical subjects

N Yamaguchi

Publications and source records attributed to N Yamaguchi.

At least 865 records · Page 48Linked to original sources
PubMed1980

Association of simian virus 40 T antigen with replicating nucleoprotein complexes of simian virus 40.

An immunoprecipitation assay was established for simian virus 40 T-antigen-bound nucleoprotein complexes by means of precipitation with sera from hamsters bearing simian virus 40-induced tumors. About 80% of simian virus 40 replicating nucleoprotein complexes in various stages of replication were immunoprecipitated. In contrast, less than 21% of mature nucleoprotein complexes were immunoprecipitated. Pulse-chase experiments showed that T antigen was lost from most of the nucleoprotein complexes concurrently with completion of DNA replication. T antigen induced by dl-940, a mutant with a deletion in the region coding for small T antigen, was also associated with most of the replicating nucleoprotein complexes. Once bound with replicating nucleoprotein complexes at the permissive temperature, thermolabile T antigen induced by tsA900 remained associated with the complexes during elongation of the replicating DNA chain at the restrictive temperature. These results suggest that simian virus 40 T antigen (probably large T antigen) associates with nucleoprotein complexes at or before initiation of DNA replication and that the majority of the T antigen dissociates from the nucleoprotein complexes simultaneously with completion of DNA replication.

Antigens, Neoplasm↗
PubMed1980

Effects of polyamines on ethylmorphine N-demethylation in rat liver microsomes.

The time course linearity of ethylmorphine N-demethylation was improved by the addition of polyamines to the reaction mixture. The most remarkable effect on the time course linearity of ethylmorphine N-demethylation was observed when spermine was used. The apparent stimulatory effect of spermine was decreased remarkably by the simultaneous addition of EDTA to inhibit lipid peroxidation. Similar results were observed when an additional lipid peroxidation inhibitor such as Co2+, Mn2+ or 2,2'-bipyridine was used in place of EDTA. Hydrogen peroxide-dependent ethylmorphine N-demethylation activity in rat liver microsomes was not influenced by the addition of spermine. In addition, neither lipid peroxides formation nor the stimulatory effects of polyamines on ethylmorphine N-demethylation was observed in the reconstituted monooxygenase system. These results suggest that the inhibitory effects of polyamines on lipid peroxidation might be responsible for the stimulatory effects on drug oxidations.

Animals↗
PubMed1980

Studies of maternal and fetal 11-deoxycorticosterone, corticosterone,18-hydroxycorticosterone and aldosterone in normal and toxemic pregnancy.

Simultaneous determination of maternal and fetal plasma 11-deoxycorticosterone (DOC), corticosterone (B), 18-hydroxycorticosterone (18OH-B) and aldosterone (ALDO) in normal and toxemic pregnancies was performed by utilizing a newly developed radioimmunoassay. The mean levels of plasma DOC and ALDO in normal term pregnancy were significantly higher than those of nonpregnant women. Comparing the mean levels of umbilical arterial plasma to those in maternal plasma at delivery, DOC and ALDO were consistently higher in the former, while B was higher in the latter, and 18OH-B was largely unchanged. However, no umbilical arteriovenous gradient was found in any corticosteroid measured. In toxemia of pregnancy, the corticosteroid levels in the maternal plasma were lower than those in normal pregnancies, and in umbilical arterial plasma, B was significantly higher and 18OH-B and ALDO remained almost the same as those in normal pregnancy. Thus, it appears that ALDO synthesis in mother in normal term pregnancy was enhanced but in toxemia of pregnancy it was suppressed, while in the fetus, it was enhanced not only in normal pregnancy but also in toxemia of pregnancy.

18-Hydroxycorticosterone↗
PubMed1980

[Mortality rates by causes of deaths in the area aggregated by dyeing factories in Kyoto (author's transl)].

In 1971 and 1973, Yoshida, et al. reported a higher relative risk of urinary bladder cancer among the workers of dyeing factories in Kyoto city. In order to confirm this, death certificates in Kyoto city from 1969 to 1972 were retrospectively investigated. Kyoto city was devided into three areas, that is, areas with high, medium and low clusterings of dyeing factories, and the differences of the mortality rates of all causes of deaths among these three areas were examined. As a result of this study, a statistically significant difference of the mortality rate of bladder cancer could not be found for males. But, the relative risk of bladder cancer in the areas with high and medium clusterings of dyeing factories compared to the area with low was found to be 1.45. Therefore, the relationship between dyeing work and bladder cancer could not necessarily be denied. It is, thus, necessary to carry out a prospective study, by which a more precise result can be obtained. In addition, our study revealed a significantly high mortality rate of skin cancer among the areas with high and medium clusterings of dyeing factories for males, observing a relative risk of 3.88. The observed association between skin cancer and dyeing work should be further studied.

Aged↗
PubMed1979

Recovery from alexia without agraphia: report of an autopsy.

The patient is a 58-year-old Japanese teacher of German literature who suffered twice from cerebrovascular accidents, showing alexia without agraphia. Pathological examination showed an old infarct in the posterior two-thirds of the fusiform and almost the whole lingual gyrus, involving the posterior border of the parahippocampal gyrus in the left hemisphere. The left cuneus and the calcarine cortex were preserved. There was degeneration of the lower third of the splenium of the corpus callosum, extending to its occipital radiation and tapetum on both sides. Comparing clinico-pathological findings of the 31 known autopsy cases, it was proposed that the lesion of the left spleno-lingual system produces alexia without agraphia but it may ameliorate. In addition, when spleno-cuneate system is also involved alexia becomes persistent and it may accompany object agnosia or optic aphasia.

Agraphia↗
PubMed1979

Establishment and characterization of Indian muntjak cell lines transformed with simian virus 40.

Kidney cells of an Indian muntjak were transformed with simian virus 40 (SV40). The transformation efficiency of the tertiary cultures was very high when estimated by the agar suspension culture method. The efficiency was about 0.015% when infected at an input multiplicity of 0.4 p.f.u./cell. Clonal cell lines were established from the colonies in soft agar medium. Most of the cell lines and their subclones produced a small amount of infectious SV40. The SV40 virion antigen-positive cells in a clone increased from 0.2% to about 40% by the treatment with mitomycin C. More than 70% of the cells in two cell lines were normal in G- and C-banded karyotypes, indicating that chromosomal change is not a necessary step in the process of transformation of the Indian muntjak cells with SV40.

Animals↗
PubMed1979

First autopsy report of a multiple sclerosis case in Hokuriku District of Japan.

The first autopsy of a case of multiple sclerosis from the District of Hokuriku was reported. The patient, a 50-year-old house-wife, born in Toyama Prefecture, had noticed a paresthesia of her face, fatigue, numbness and weakness in the right limbs, dimness of vision and gait disturbance at ave 44. Furthermore, in the course of the disease, she had suffered from visual disorder, tetraplegia, hyperreflexia, pyramidal signs and cerebellar syndroms such as dysarthria, nystagmus, intention tremor and ataxia. She also showed symptoms of euphoria and dementia. After a course of six years she died of bronchopneumonia. Remissions and exacerbations were noted four times during her clinical history. Histopathologically, there were many recent and old demyelinating lesions of varying sizes and shapes in all parts of the central nervous system, namely the cerebrum, brainstem, spinal cord and optic nerve. In contrast to the clinical symptoms, the cerebellum itself revealed less plaques than the other areas of the brain. According to the observed distributions of the lesions, our case can be classified as belonging to the optico-cerebro-spinal type in the Ikuta and Zimmerman classification. The demyelinated lesions were characterized by a perivenular distribution of the plaques, lack of tissue necrosis, paucity of inflammatory reaction and marked fibrous gliosis of varying degrees.

Bronchopneumonia↗