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Biomedical subjects

N Yamaguchi

Publications and source records attributed to N Yamaguchi.

At least 793 records · Page 44Linked to original sources
PubMed1984

Prostaglandin D2 inhibits the proliferation of human malignant tumor cells.

The cytotoxic effect of prostaglandin (PG) D2, PGE1 and PGF2 alpha was examined on human osteosarcoma cells (KSu cell line) in vitro, and PGD2 was most effective. DNA, RNA and protein syntheses of KSu cells were also found to be inhibited by PGD2 at a concentration of 5 micrograms/ml. Furthermore, the proliferation of various human malignant tumor cells was inhibited by PGD2 without exception so far. These results suggest that PGD2 shows an anti-neoplastic effect on a variety of human malignant tumor cells.

Antineoplastic Agents↗
PubMed1984

gamma-Glutamyltranspeptidase activity in a human pancreatic cancer cell line (HPC-Y1) in serum-free chemically defined medium.

gamma-Glutamyltranspeptidase (gamma-GTP) activity was found in a human pancreatic cancer cell line, HPC-Y1, cultivated in a serum-free chemically defined medium. The gamma-GTP stained in the cytoplasms as fine granules and was produced constantly in a protein-free chemically defined medium. The detergent- or protease-solubilized gamma-GTP of HPC-Y1 cells in serum-free medium was compared with the gamma-GTPs extracted from HPC-Y1 cells in serum-containing medium, human pancreatic carcinoma and normal human pancreas. Their molecular weights, electrophoretic mobilities, affinity to Concanavalin A-Sepharose and isoelectric points were almost identical. No cancer specific properties in the gamma-GTP derived from human pancreatic carcinoma cell line were found by these analyses. However, the serum-free spent medium of HPC-Y1 cells was useful for purifying the gamma-GTP secreted from the human pancreatic carcinoma cell line, since it is not necessary to separate the contaminated serum components that are usually added for cell cultures and the extraction procedures could induce minor structural change and/or artificial modification of gamma-GTP.

Cell Line↗
PubMed1984

Effect of maternal antigenic stimulation on the active immune response of their offspring. Relationship between the immune reactivity of mother mice and the induction of suppression in their young.

Pregnant mice were stimulated by heterologous erythrocyte and protein antigen, and the active immune responses of their offspring as measured by plaque-forming cells (PFC) were investigated. In offspring derived from mothers immunized by a suitable amount of T-dependent antigen, clear-cut suppression of development of specific PFC in spleen was observed over a significant period after delivery. The mechanism of this suppression was investigated, and the following results were obtained. When the heterologous erythrocyte was used as antigen, the more the specific PFC developed in the mother spleen, the stronger the suppression of PFC observed in their offspring. However, it is worthy of note that passive administration of antibody to pregnant mice did not induce suppression in their young. In case of the protein antigen ovalbumin (OVA), pregnant mice had to be injected with a suitable amount of antigen, along with aluminium hydroxide, for either primary or secondary stimulus to induce the suppression of specific PFC in their offspring. Soluble OVA administered to pregnant mice was not effective for inducing suppression in the offspring. Based on these results, some possible mechanisms are discussed concerning specific PFC suppression in the offspring when pregnant mice are stimulated.

Adjuvants, Immunologic↗
PubMed1984

Two classes of transformation-deficient, immortalization-positive simian virus 40 mutants constructed by making three-base insertions in the T antigen gene.

We constructed two mutants of simian virus 40 (SV40) by introducing a three-base duplication at AvaII cutting sites within the large T antigen coding region, and we examined these mutants for their abilities to replicate in monkey GC7 cells, to transform rat cell line 3Y1 cells, and to transform and immortalize primary cells from newborn rats. Neither of the mutants could replicate in GC7 cells. One mutant with the duplication at 0.335 SV40 map units (m.u.) (inA942) could transform 3Y1 cells, but the other mutant with the duplication at 0.636 m.u. (inA941) could not. The two mutants could not transform primary rat cells but retained immortalization activity. The results suggest that transformation of primary cells by SV40 requires at least two distinct activities of the large T antigen, one of which can be replaced by a cellular function(s) expressed in immortalized 3Y1 cells.

Animals↗
PubMed1984

Correlation between endogenous noradrenaline and glucose released from the liver upon hepatic sympathetic nerve stimulation in anesthetized dogs.

The metabolic role of neurally released noradrenaline (NA) was studied in the liver of anesthetized dogs. Sustained stimulation with various frequencies was directly applied on the anterior plexus of hepatic nerves. Stimulation-induced changes in plasma concentrations of endogenous catecholamines in hepatic venous blood were determined in correlation with concomitant changes in those of glucose (GL). Mean basal values for hepatic venous NA, adrenaline, dopamine, and GL were 0.062, 0.022, 0.032 ng/mL, and 97.9 mg%, respectively. Among these catecholamines, NA was the only one being released significantly during stimulation. While hepatic venous NA increased rapidly during stimulation, being maximum within 3 min, hepatic venous GL increased gradually, reaching a maximum value 5 min after the onset of stimulation. A highly significant correlation (r = 0.90, P less than 0.001) was found between changes in hepatic venous NA and GL concentrations observed during stimulation at various frequencies (2-16 Hz). However, hepatic vasoconstricting responses to stimulation were not correlated with increased hepatic venous GL. An alpha-blockade with phentolamine (2 mg/kg, iv) resulted in diminished release of GL by approximately 50% (P less than 0.05) and reduced hepatic arterial vasoconstriction by approximately 47% (P less than 0.01) upon stimulation (8 Hz, 5 min), even though NA release was markedly enhanced. We conclude that in the dog, NA is the sole catecholamine released within the liver in response to direct hepatic nerve stimulation, and NA thus released mediates the hepatic glycogenolysis via alpha-adrenoceptors.

Animals↗
PubMed1984

CT findings of the interval form of carbon monoxide poisoning compared with neuropathological findings.

Cerebral computed tomography findings were described in 2 clinical cases of the interval form of carbon monoxide poisoning and comparison with postmortem CT finding of an autopsy case was made. There was low density in the bilateral frontal region, centrum semiovale and pallidal parts. In the course of the disease, the degree of low density in the white matter showed a tendency to diminish but it became more apparent in the pallidal parts. Myelinopathic white matter lesion in an autopsy material was recognized as a low density area in CT, which is identical with that seen in clinical cases.

Adult↗
PubMed1984

Separation and characterization of macrophage precursors and of interleukin 2-responding cells from nylon wool-nonadherent murine spleen cells by using Bauhinia purpurea agglutinin.

Precursors of macrophages were found to be enriched in nylon wool-nonadherent cells which are often used as purified T cells. By using a 2-step agglutination sedimentation method with Bauhinia purpurea agglutinin (BPA), the precursors of macrophages which were enabled to proliferate and differentiate by the addition of colony-stimulating factor (CSF) or high concentrations of concanavalin A (Con A) were exclusively separated into a nylon wool-nonadherent, BPA-agglutinated (bottom) fraction. Cells responsive to some kind of factor(s) other than CSF in Con A supernatants (Con A-Sup) were also fractionated into the bottom fraction. Under these conditions, T cells were separated into both BPA-nonagglutinated (top) and agglutinated (bottom) fractions. The proliferative response of the cells in the top fraction was higher than that in the bottom fraction when they were stimulated with an optimal concentration of Con A (3 micrograms/ml). As assessed by the Con A pulse experiments, T cells in the bottom fraction required larger amounts of interleukin 2 (I1-2) than those in the top fraction for proliferation and the growth of T cells in both fractions was completely dependent upon I1-2.

Adhesiveness↗
PubMed1984

Co-localization of SV40 T antigen and p53 with immunological analogues of microtubule-associated protein-1 on the nuclear skeleton.

Rat SV-3Y1 cells were stained with double immunofluorescence. Treatment of cells with detergent and salt removed about 80% of the antigens and revealed immunofluorescent flecks of the SV40 large T antigen and p53 bound to the nuclear skeleton. These flecks exactly corresponded to the fluorescent spots produced by antibodies against microtubule associated protein-1. The MAP-1 analogues may function in the initiation of DNA synthesis through the interaction with T-antigen and p53.

Animals↗
PubMed1984

[A longitudinal study of specific gravities of whole blood in dyestuff plant workers].

Specific gravities of whole blood (GB) have been used widely as a screening test of anemia in industrial surveillance systems in Japan. The recent spread of electronic computers enables us to make effective use of a large quantity of information and GB could be used to screen examinees more accurately if the various factors which can bring about fluctuations in GB or the data obtained through past health examinations are taken into consideration. Time trends of GB can be explained by the combination of the physiological effect of aging, environmental factors such as diet or working conditions, and the birth cohort effect. The present study was aimed to identify the factors which bring about fluctuations in GB through longitudinal as well as cross-sectional observations. The study subjects consisted of 1,105 male workers engaged in dyestuff production work or clerical work at a dyestuff plant located in Tokyo during the period from 1953 to 1976. Though a negative association was found between GB and the age of workers through cross-sectional observations, it was found through longitudinal observations that the individual GB had a tendency to rise during the period in each birth cohort. These facts suggest that some environmental factors acted so as to raise the individual GB during this period in opposition to the physiological effect of aging to lower it. In order to evaluate the associations of educational history, working conditions, age and physique of workers with GB, information on these factors obtained through health examinations in 1960, 1965, 1970 and 1975 was analyzed separately by the multi-dimensional contingency table method. As a result, it was demonstrated that GB was directly related to all of these factors in 1960 and 1965, to age and physique in 1970 and only to age in 1975. These results suggest that environmental factors associated with educational history or working conditions played a greater part in the earlier periods when the average GB was not as high as in the later periods. In summary, the efficiency of GB as a screening test will be considerably improved if the judgment criteria utilize information about these environmental factors as well as the physiological effect of aging based on the information obtained from this study.

Adult↗
PubMed1984

Purification of a lamprey complement protein homologous to the third component of the mammalian complement system.

A lamprey protein homologous to the third component of mammalian complement was isolated from lamprey plasma and was tentatively designated lamprey C3. Lamprey C3 is a major protein in lamprey serum with electrophoretic mobility of beta-globulin and with m.w. of 190,000. It consists of three polypeptide chains (84,000-alpha, 74,000-beta, and 32,000-gamma chains) linked by disulfide bonds. The protein retains a unique internal thiolester bond on the alpha-chain that is cleaved on methylamine treatment or on limited proteolysis with trypsin. Lamprey C3 by itself could not bind to zymosan or rabbit red cells, but it could covalently bind to these substances when activated by other factors present in lamprey serum. The binding of lamprey C3 to activating surfaces is mediated by covalent bonds and is accompanied by limited proteolysis of the alpha-chain. A fragment with an m.w. of 35,000 containing the internal thiolester site was isolated from methylamine-treated lamprey C3 bound to activated thiol-Sepharose by extensive tryptic digestion followed by dithiothreitol treatment. Lamprey C3 functions as the essential factor in phagocytosis of rabbit red cells by lamprey phagocytes. However, it is not involved in naturally occurring hemolytic activity in lamprey serum.

Animals↗
PubMed1984

Health status of Indochinese refugees in Japan: statistical analyses on anemia, eosinophilia and serum alkaline phosphatase.

Detailed statistical analyses were attempted on anemia, eosinophilia and elevation in serum alkaline phosphatase in the Indochinese refugees in Japan. A high statistical correlation was found between hemoglobin concentration and hematocrit for most of the refugees except the Cambodian females. Refugees with parasitic infections, particularly hookworm infection had significantly lower values for hemoglobin concentration and hematocrit. Significant eosinophilia was observed in the refugees infected with hookworms, Strongyloides stercoralis, Rhabditis sp., Endolimax nana and/or Hymenolepis nana. However, these parasites were found in the same subpopulations more frequently than expected by chance. Elevation in serum alkaline phosphatase was observed in young Cambodian immigrants. Analyses showed that the variations of this enzyme could be well predictable by those of enzymes such as serum glutamic oxaloacetic transaminase, which are good markers for liver functions, in Cambodian immigrants, 13-24 of age, whereas no such correlation was observed in non-Cambodians of the same age group.

Adolescent↗
PubMed1984

[A report of self-amputation of the penis with subsequent complication of myiasis].

A 38-year-old male was admitted to our emergency ward on Oct. 27, 1982, because of severe pain at his penoscrotum. Upon physical finding on admission, his penis was found to have been completely amputated 2 cm distally near the root with a razor by himself to commit suicide a few days before admission. On the affected part were much coagulated blood mass and slough and moreover there were 50 maggots about 5 mm long swarming and wrigling, but no bleeding yet and little sign of inflammation. After exclusion of these maggots and cleaning the slashed surface, cutaneous urethrostomy was performed. Postoperative course was favorable but we could not prevent the patient from leaping to his death 45 days after the operation. Self-amputation of the penis with subsequent complication of myiasis is a very rare condition. Since the report of self-amputation of the penis by Matsushita in 1937, this case is the 16 th in Japan. In most cases the patients had mental disorder. In this case the patient was schizoid. On the other hand, 133 cases of myiasis were reported in Japan from 1903 to 1983. In the present case the species that caused myiasis was Lucilia ampullacea. A very rare case of self-amputation of the penis with subsequent complication of myiasis is documented with a review of the literature on this subject.

Adult↗
PubMed1983

Electric convulsive therapy (ECT) increases plasma and red blood cell haloperidol neuroleptic activities.

In nine schizophrenic patients (five males and four females) on haloperidol treatment, plasma and red blood cell (RBC) haloperidol neuroleptic activities were measured before and after ECT by radioreceptor assay. Five patients randomly selected from these patients also served as controls on another occasion and neuroleptic activities in plasma and RBC were examined before and after the premedication only. All patients given ECT showed a considerable increase in plasma and RBC haloperidol neuroleptic activities after ECT (% increase in plasma neuroleptic activity, 28-409%; mean + SD, 136 +/- 155%, P less than 0.005, Wilcoxon test; % increase in RBC neuroleptic activity, 11-121%; mean + SD, 59 +/- 40%, P less than 0.005). However, no significant increase was observed for either plasma or RBC haloperidol neuroleptic activity, when patients were examined after premedication only. It was suggested that ECT induced a transient redistribution of haloperidol. It remains to be studied whether this phenomenon is causally related to the previous observation that the combination therapy of ECT and neuroleptics is more effective in the treatment of schizophrenia than ECT alone.

Adult↗
PubMed1983

Establishment and characterization of a carcinoembryonic antigen (CEA)-producing cell line from a human carcinoma of the exocrine pancreas.

A human carcinoembryonic antigen (CEA)-producing cell line, T3M-4, has been established from explant cultures of a primary human pancreatic exocrine adenocarcinoma transplanted into nude mice. The tumor had metastasized in the patient. The tumor obtained from metastatic lymph nodes was the initial source for implantation in athymic nude mice. In the primary culture, host fibroblasts were eliminated by the use of the antiserum raised against nude mouse cells. T3M-4 cells have been continuously propagated in vitro during the past 26 months. The cells grew in a monolayered sheet with about 31 hours of population doubling time. The cells exhibited epithelial morphologic features resembling the structure of the original tumor, and they showed tumor takes when inoculated into athymic nude mice. Xenografts established from the cell line have retained a similar histology to the original tumor on serial transplantation. Chromosomal analysis revealed the cell line to be a human aneuploid one with a hyperdiploid mode. T3M-4 cells possess the characteristic function of CEA secretion in vitro in culture and in vivo in nude mice bearing the tumors produced by inoculation with the cultured cells. In view of these characteristics, T3M-4 cell line represents a new human pancreatic exocrine adenocarcinoma cell line that produces CEA.

Adenocarcinoma↗