Search PubMed⌕ Search

Biomedical subjects

M Kubo

Publications and source records attributed to M Kubo.

At least 469 records · Page 26Linked to original sources
PubMed1989

mRNA secondary structure in an open reading frame reduces translation efficiency in Bacillus subtilis.

The structural gene for thermostable neutral protease, nprM, has only one stacking region, whose energy is -16.3 kcal/mol (-68.2 kJ/mol). Mutations for increasing (-30.8 kcal/mol [128.9 kJ/mol] and decreasing (-5.0 kcal/mol [-20.9 kJ/mol]) the energy of the stacking region were introduced in nprM on the recombinant plasmid pMK1 by using site-directed mutagenesis without any amino acid substitutions. The resultant plasmids were designated pMK2 and pMK3, respectively. The enzyme productivity of the pMK2 carrier was about 40% lower than that of pMK1, whereas the productivity of the pMK3 carrier was about 5% higher. The higher the stability of the stacking regions, the lower the enzyme productivity that was observed. mRNA concentrations were almost the same in the cells harboring these three plasmids. These results indicate that the secondary structure of mRNA reduces the translation efficiency.

Bacillus subtilis↗
PubMed1989

Studies on medicinal resources from livestock. I. Anti-allergic effects of pig bile. (1).

Anti-allergic activities of animal biles and commercially available bile acids were evaluated in experimental allergic disease models. Pig bile exhibited marked preventive effects on the models of delayed-type hypersensitivity (type IV allergy), picryl chloride-induced contact dermatitis (PC-CD) and sheep red blood cells (SRBC)-induced footpad swelling in mice. Fel ursi (dried bear gallbladder) also had an inhibitory effect on PC-CD, whereas ox bile, chicken bile and bile acids had no effect on ether of the models.

Animals↗
PubMed1989

Inhibitory effect of extracts of muscles of mackerel (Scomber japonicus Houttuyn) on hepatic glycogenolysis in rats.

The effects of extracts of muscles of mackerel (Scomber japonicus; M-ext) on hepatic glycogenolysis were investigated by a rat liver perfusion method. M-ext inhibited glucagon- and cyclic adenosine monophosphate (AMP)-induced glycogenolysis but was ineffective on phenylephrine-induced glycogenolysis. The contents of hepatic glycogen and cyclic AMP, and phosphorylase and glycogen synthase activities in liver were measured after perfusion with glucagon. M-ext inhibited the increase of cyclic AMP and activation of phosphorylase. It is considered that M-ext inhibits hepatic glycogenolysis caused by glucagon through a cyclic AMP-dependent mechanism.

Animals↗
PubMed1989

[Pharmacological study on citrus fruits. I. Anti-allergic effect of fruit of Citrus unshiu Markovich (1)].

A study was carried out to examine the effect of 50% ethanolic extract from green fruit of Citrus unshiu Markovich on type I, II and IV allergic reactions. Forty eight-hour homologous passive cutaneous anaphylaxis (PCA) in rats as a typical model of the type I reaction was significantly inhibited by the oral administration of the extract. Complement-dependent cytolysis of sheep red blood cell as a typical model of the type II reaction was significantly inhibited by incubation with it. Contact dermatitis in mice as a model of the type IV reaction caused by picryl chloride or sheep red blood cell was significantly inhibited by the oral application of it. The anti-allergic actions decreased with the growth of fruit of Citrus unshiu. These results suggested that the 50% ethanolic extract from green fruit of Citrus unshiu have anti-allergic actions against the type I, II and IV reactions.

Animals↗
PubMed1989

[Cytotoxicity of Corylifoliae fructus. I. Isolation of the effective compound and the cytotoxicity].

The ethanol extract of Psoraleae Fructus (Psoralea corylifolia L.) was found to have cytotoxic activity against L929-cells in cell culture. The active compound was isolated by column chromatography on silica gel and identified as bakuchiol by means of spectral evidence. The cytotoxic activity of bakuchiol in cell culture was observed in short time and found to be unreversible. The mechanism of the cytotoxic activity was considered to be due to an injury of cell membrane from electron microscopic observation and hemolytic activity.

Animals↗
PubMed1989

[Cytotoxicity of corylifoliae fructus. II. Cytotoxicity of bakuchiol and the analogues].

Bakuchiol is a major component of Corylifoliae Fructus (Psoralea corylifolia L.) and has been clarified to have cytotoxic activity. The chemical structure-cytotoxic activity relationship of bakuchiol was investigated by means of cytotoxic activity of synthesized analogues of bakuchiol and phenol. It was proved that an alkyl group was necessary for cytotoxic activity. But the double bonds in the unsaturated hydro-carbon group exerted but little influence on the cytotoxic activity. The cytotoxic activity of bakuchiol was the strongest as compared with that of the analogues examined.

Cells, Cultured↗
PubMed1989

[Pharmacological study on Agkistrodon blomhoffii blomhoffii BOIE. I. Effect of the 50% ethanolic extract on experimental gastric ulceration].

Anti-ulcerogenic activities of a 50% ethanolic extract [( M]) from whole body of Agkistrodon blomhoffii blomhoffii BOIE were investigated in rats. [M] at oral doses of 250-500 mg/kg was found to show a prophylactic effect on the water-immersion stress- and ethanol-induced ulcer and a remedial effect on acetic acid-induced ulcer, but not Shay-ulcer in pylorus-ligated rats and indomethacin-induced ulcer. [M] increased the gastric mucosal blood flow in intact rats and improved the decrease of the blood flow in acetic acid-induced ulcer rats. [M] inhibited the decrease in content of hexosamine of gastric mucosa in rats treated with acetic acid. These results suggest that [M] have a prophylactic effect on ulcerogenics, and an anti-ulcer effect by the increase and/or maintenance of gastric mucosal blood flow and hexosamine, but further investigations are required to understand the mechanism involved.

Animals↗
PubMed1989

Encephalitis of cattle caused by Iriki isolate, a new strain belonging to Akabane virus.

A disease characterized by nervous signs was found in 10 calves in two districts in Kagoshima Prefecture, Japan, from October to November, 1984. Histopathological changes of nonpurulent encephalitis were found in every case. An agent, named Iriki isolate, was isolated from the cerebellum of a calf in HmLu-1 cell cultures. All of the affected calves possessed neutralizing antibody to the virus. A high seropositive rate to the virus in cohabiting cattle and cattle kept in the epizootic area, and seroconversion to the virus in 1984, were disclosed. Experimental infection of calves with Iriki isolate produced severe nervous signs and histopathological changes similar to those of the natural infection. These seroepidemiological findings and animal experiments established that Iriki isolate is the causative agent of the disease. Iriki isolate was considered as a variant of Akabane virus since the virus showed cross reaction with Akabane virus in virus neutralization tests.

Animals↗
PubMed1989

[Changes in chewing rhythm during repetitive series of mastication in normal adults as a function of time elapsed and the four basic taste stimuli].

Surface EMG activities in the masseter muscle were recorded from 8 healthy men with normal permanent dentition during habitual chewing of a small cube of synthetic cellulose sponge which had absorbed distilled water. Three parameters of chewing rhythm, viz., cycle time, duration, and interval, were shown as the respective averages of 40 measurements of the EMG traces of a masticatory series of 42 consecutive chewing strokes. Twenty-five recording sessions, in each of which the above masticatory series were repeated 10 times in a day with a 5 minutes' recess between each series, were performed on a subject during continuous 25 days. The amount of scatter in the distribution of 25 cycle time values was great at the 1st masticatory series, gradually decreased to reach a node relatively free from the dispersion at the 5th series, and then gradually increased from the 6th to 10th series. The same phenomenon was observed in all 8 subjects, although there was a small difference among them in the number of the series where the node was apparent. The average of 5 cycle time values was used to compare in the same subject the effect of chewing the cellulose sponge which had absorbed one of the 4 basic taste solutions with the effect of chewing that which had absorbed distilled water. The average value while chewing the sponge which had absorbed 1 M saccharose was significantly lower in the subjects who obtained a relatively large average value during distilled water sponge-chewing, whereas it was significantly greater in those who obtained a relatively small average value while chewing the sponge which had absorbed distilled water. The other 3 taste stimuli induced a significant increase in the average value in most subjects.

Adult↗
PubMed1989

[Effect of Impletol injection into paratonsillar tissue on abnormal sensation in the throat].

If the abnormal sensation, such as a lump or choking, in the throat was mainly caused by inflammatory changes in the palatine tonsils or their surrounding tissues and conveyed via vagal nerve branches distributing there, the sensation might be reduced by topically injected Impletol (Procaine and caffeine in saline solution), i.e. Impletol test for focal tonsillitis. One hundred patients with abnormal sensation in the throat were injected Impletol (Impletol group), 50 patients were injected saline solution alone (Saline group) and 50 patients had injection needle simply inserted into the peritonsillar tissues (Needle group). The Impletol group showed the best result and was followed by Saline group and then Needle group. Namely, the degree of sensation reduced by 80% or more in 38% of the Impletol group and by 50% or more in 62% of them. Those rates were 26% and 60% for Saline group and 28% and 52% for Needle group, respectively. Though the results were indicative of the effectiveness of the Impletol injection for the abnormal sensation in the throat, the difference among these three groups was not statistically significant.

Adult↗
PubMed1989

[A case of massive hepatoma which responded to SMANCS/Lipiodol regimen with intra-arterial infusion].

Transcatheter arterial chemotherapy (SMANCS/lipiodol) was applied to massive hepatoma, which had a high AFP 213,000 ng/ml, A-P shunt, tumor thrombosis and metastatic lung cancer. After 3 months, the AFP value reduced to 18 ng/ml, massive hepatoma and the A-P shunt disappeared, but AFP-negative nodular hepatoma recurred around initial hepatoma. Each time, we injected SMANCS/lipiodol to the recurring hepatoma. The therapy in the initial stage was not so effective. The portal vein was not observed in the initial stage, but appeared after the second dosage. Metastatic lung cancer was declining in the initial dosage and 23 months later disappeared after the third dosage. The massive hepatoma occupied entirely the rt. lobe of the liver. The patient lived for 4 years, had total admission periods of 190 days and could return to life in society. In this case, we considered that transcatheter arterial chemotherapy (SMANCS/lipiodol) had remarkable effects.

Antibiotics, Antineoplastic↗
PubMed1989

[Visible-light cured resin. Selection of reducing agent amine, its appropriate amount and effect on physical properties].

Studies were done to improve the physical properties, especially degree of conversion of visible-light cured resin (VLCR), and accordingly to lower its water sorption and solubility in water. Trial products of VLCR were prepared using various kinds of amine, reducing agent, and the photoinitiator to be mixed with cyclophosphazene monomer, 4 PN-(TF)1-(EMA)7. As amines ethyl-p-dimethylaminobenzoate (DMAB), methacryloxyethyl-p- dimethylaminobenzoate (DMAB-EMA) and methacryloxyglycidyl-p-dimethylaminobenzoate (DMAB-GMA) were used. Of their set products immersed in water and MeOH, their water sorption, solubility in water, MeOH sorption and solubility in MeOH were examined. The resin with DMAB-EMA used was preferable, showing comparatively small solubility. Next, VLCR, with various amounts of DMAB-EMA mixed, 0.5-5.0 in mol ratio to photosensitizer (CQ + DB), and of their set products water sorption, solubility in water, MeOH sorption, solubility in MeOH, THF sorption and their mechanical properties after immersion in water were examined. Immersion of the resin products in water and MeOH for 30 days, lowered the solubility in water and MeOH to a minimum at the mixing ratio of 3.0 in mol ratio. Solubility in MeOH (HPLC) became minimum at 2.0 in mol ratio, and at less than 2.0, the photosensitizer and monomer were dissolved, while at more than 2.0, the photosensitizer and DMAB-EMA were dissolved. THF sorption decreased in accordance with the increase in the mixed amount of DMAB-EMA, became almost constant at more than 3.0 in mol ratio. The compressive strength of set product after immersion in water for 7 days increased in accordance with the increase of the mixed amount of DMAB-EMA, while the transverse strength also increased up to 2.0 in mol ratio. The optimum reducing agent to be mixed with VLCR was DMAB-EMA, and the mixing ratio should be 2.0-3.0 in mol ratio to photosensitizer.

Acrylic Resins↗
PubMed1988

Phosphorylation of calmodulin on threonine residue(s) by cytosol prepared from the adrenal cortex.

During the course of experiments examining Ca2+/calmodulin-dependent protein phosphorylation by cytosol prepared from the outer and inner zones of the guinea pig adrenal cortex, it appeared that the calmodulin added to incubation mixtures was undergoing phosphorylation. This was subsequently confirmed by immunoprecipitation following phenyl-Sepharose purification of the phosphocalmodulin. The phosphorylation of calmodulin was maximal in the absence of calcium, and markedly increased by the presence of poly-basic amino acids. Phosphoamino acid analysis revealed that calmodulin was phosphorylated exclusively on threonine residue(s). It was of interest to note that the phosphorylation of calmodulin was always considerably more intense with the cytosol prepared from the inner adrenocortical zone than with cytosol prepared from the outer zone.

Adrenal Cortex↗
PubMed1988

Analysis of two distinct B cell activation pathways mediated by a monoclonal T helper cell. II. T helper cell secretion of interleukin 4 selectively inhibits antigen-specific B cell activation by cognate, but not noncognate, interactions with T cells.

A single monoclonal T helper (Th) clone can activate B cells in two distinct pathways; a cognate pathway requiring a major histocompatibility complex (MHC)-restricted T-B cell interaction, and a noncognate pathway not requiring an MHC-restricted T-B cell interaction. The present study was undertaken to investigate whether Th cells mediating a given immune response provide further regulatory function to B cells other than helper function. It was demonstrated that conditions of high antigen concentration which activate a noncognate B cell activation pathway simultaneously inhibit IgG responses. The inhibition is shown to be mediated by the T cell factor interleukin 4, produced by activated cloned Th cells. The inhibitory effect of this factor is directed to B cells and is MHC-unrestricted, antigen-nonspecific, and IgG class-specific. In addition to being susceptible to the effects of augmenting cells and suppressor cells, cloned Th cell populations can therefore themselves function as regulatory cells to inhibit IgG responses when stimulated with high dose of specific antigen. These results indicate that Th cells function to regulate B cells both positively and negatively, depending upon the activation conditions.

Animals↗
PubMed1988

Epitopes associated with major histocompatibility complex (MHC) restriction site of T cells. IV. I-J epitopes on MHC-restricted cloned T cells.

We studied the expression of an I-Jk epitope on class II-restricted cloned L3T4+ T cells established from H-2k, H-2b, F1 and semiallogeneic radiation bone marrow chimeras by the inhibition of antigen-induced T cell proliferation and in vitro secondary antibody response, and by the direct immunofluorescence with a monoclonal anti-I-Jk. Both I-Ak- and I-Ek-restricted T cells were shown to carry the identical I-Jk epitope regardless of their genotypic origins, antigen specificity, and helper or suppressor function. None of the I-Ab-restricted clones derived from similar animals showed the I-Jk epitope. This isomorphism, regardless of the restriction specificity for I-Ak or I-Ek, contradicts the idea that I-J is an idiotypic determinant on class II-restricted T cell antigen receptor (TcR). In fact, the I-Jk epitope was not comodulated with TcR/T3 complex when incubated with an anti-T3 antibody, indicating that I-J is a new isomorphic receptor for self different from TcR alpha/beta heterodimers.

Animals↗
PubMed1988

Cholesterol-lowering effect of N-(alpha-methylbenzyl)linoleamide (melinamide) in cholesterol-fed diabetic rats.

Cholesterol loading of diabetic rats is known to induce marked hyperlipoproteinaemia, and we have reported that enhancement of the activity of intestinal acyl-CoA:cholesterol acyltransferase (ACAT), one of the key enzymes involved in cholesterol absorption, might play an important role in the development of hypercholesterolaemia in these animals. In the present study, we have shown that treatment with N-(alpha-methylbenzyl)linoleamide (melinamide), a new hypocholesterolaemic drug, caused a substantial decrease of the enhanced intestinal ACAT activity in diabetic rats, but did not affect intestinal cholesterol esterase activity. Furthermore, marked improvement of hypercholesterolaemia in cholesterol-fed diabetic rats occurred concomitantly with the drug treatment. These results suggest that intestinal ACAT activity is closely related to the serum cholesterol level in diabetic rats, and show that melinamide lowers intestinal ACAT activity.

Animals↗
PubMed1988

Calcium-dependent protein kinase activity and protein phosphorylation in zones of the adrenal cortex.

The guinea pig adrenal cortex is composed of two chromatically distinct concentric zones. The steroidogenic response to ACTH by the two zones is likewise distinct: ACTH stimulates cholesterol side-chain cleavage activity in the outermost zone, but fails to do so in the inner zone. This despite the fact that adenylate cyclase activation by ACTH and cAMP formation are similar for the two zones. To further examine this model, protein kinase activity and protein phosphorylation have been examined. It was found that the cAMP-dependent, Ca2+/phospholipid-dependent, and Ca2+/calmodulin-dependent protein kinase activities were significantly higher in the outer zone than in the inner zone by 70, 60 and 800%, respectively. Although the physiological meaning of a zonal difference in protein kinase activity is not as yet clear, the marked difference in Ca2+/calmodulin-dependent protein kinase activity between the inner and outer zones correlates well with the marked difference in steroidogenesis that exists between the two zones. Of the Ca2+/calmodulin-dependent protein kinases known to exist, there is preliminary evidence to suggest the presence of kinase III in the guinea pig adrenal cortex. Protein phosphorylation induced by the three kinase systems in the two adrenocortical zones revealed notable differences in phosphoprotein patterns. In addition, it was found that exogenous calmodulin was phosphorylated and that the kinase responsible for this was more active in the inner zone.

Adrenal Cortex↗