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T Yabe

Publications and source records attributed to T Yabe.

At least 163 records · Page 9Linked to original sources
PubMed1987

cDNA cloning and sequencing reveals that the electrophoretically constant DR beta 2 molecules, as well as the variable DR beta 1 molecules, from HLA-DR2 subtypes have different amino acid sequences including a hypervariable region for a functionally important epitope.

Two-dimensional gel electrophoresis (2D-PAGE) of DR molecules from three different Dw subtypes (Dw2, Dw12, and FJO) of the HLA-DR2 haplotype reveals that at least two DR beta genes are expressed. Protein mixing experiments demonstrate that one of the two expressed DR beta molecules is electrophoretically variable (referred to as DR beta 1), and the other (DR beta 2) migrates constantly among DR2 subtypes. We have constructed cDNA libraries from Dw12 and FJO homozygous typing cells (HTC DHO for Dw12 and HTC FJO for FJO) and isolated DR beta cDNA clones. Four of these clones (FJO-13, DHO-8, FJO-6, and DHO-7) were sequenced, and the deduced amino acid sequences were compared with each other and with two published amino acid sequences for the DR beta molecules derived from a DR2-Dw2HTC. Prediction of the migration patterns on 2D-PAGE from the amino acid sequences of these and other DR beta molecules allows the tentative designation of the two full-length cDNA (DHO-8 and FJO-13) as coding for DR beta 2 molecules and the other two cDNA (DHO-7 and FJO-6) for DR beta 1 molecules. Amino acid sequence comparisons also show that the constantly migrating DR beta 2 molecules, as well as the electrophoretically variable DR beta 1 molecules, from Dw2, Dw12, and FJO have different primary amino acid sequences, including a clustered difference in the third hypervariable region of the polymorphic first domain.

Amino Acid Sequence↗
PubMed1987

Protein analysis of HLA-DR2.3 haplotype.

The human major histocompatibility antigens (HLA-DR, HLA-DQ, and HLA-DP), consisting of alpha and beta chains, show extensive polymorphism. Based on differences of T-cell responses, the serologically defined DR2 specificity has been divided into Dw2, Dw12, and several putative additional "Dw subtype" specificities (AZH, FJO, and MN2, which we shall designate as "DR2.3", and LD-5a). To investigate the relationships of these specificities, DR and DQ molecules were analyzed by two-dimensional gel electrophoresis (2D-PAGE). The 2D-PAGE patterns of the DR molecules are identical among DR2.3 cells. Three DR beta chain polypeptides are expressed on DR2.3 cells. The electrophoretic mobilities of two of these beta chains are different from those of beta chains from the Dw2 and Dw12 cells. The DR molecules of the LD-5a cells show similar 2D-PAGE patterns with those of DR2.3 cells. The 2D-PAGE patterns of DQ molecules are identical among DR2.3 cells. The electrophoretic mobilities of DQ beta chains are different for Dw2, Dw12, LD-5a, and DR2.3 cells. These results indicate that the AZH, FJO, and MN2 cells have identical or very similar DR and DQ molecules and constitute a third, and relatively homogeneous, subgroup ("DR2.3") of the DR2 specificity. In addition, DR2.3 cells have a unique characteristic in that they express three DR beta chains.

Antibodies, Monoclonal↗
PubMed1987

Circadian rhythm of the liver of male rats pre-treated with phenobarbital--II. Hexobarbital sleeping time and lipids content in liver and serum.

The circadian rhythm of hexobarbital sleeping time and lipids content in liver and serum were studied in 226 male Sprague-Dawley rats pretreated daily at 0800-0900 with 70 mg/kg (study 1 or 3) or 50 mg/kg (study 2) phenobarbital (PB) orally for 7 days. Thereafter, eight (study 1) or five (study 2 and 3) rats each were studied at 4-hr intervals at 1000, 1400, 1800, 2200, 0200, 0600 and 1000 through the following day. The lighting schedule in the colony was 12:12 +/- light:dark (light from 0600 to 1800). The hexobarbital sleeping times of PB-pretreated rats were generally shortened compared to the controls and no circadian rhythm was observed. PB-treatment increased slightly the liver content of cholesterol, and significantly that of triglycerides and phospholipids. Liver cholesterol and phospholipids showed circadian rhythms with peaks during the dark phase. No circadian rhythm of liver triglycerides existed. In serum, levels of triglycerides and phospholipids were slightly lowered by PB-treatment, while levels of cholesterol and beta-lipoprotein were not influenced. Serum values did not exhibit circadian rhythms.

Animals↗
PubMed1986

Predominance of nasal over temporal saccades in fast eye movement.

Quantitative analysis of saccadic eye movement caused by 20 degree amplitude gaze in horizontal plane was undertaken in 131 subjects using the Contraves' computerized oculomotor testing system. All of the subjects were free from any spontaneous nystagmus, neurological symptoms, and abnormalities of vestibular function. Both of the monocular recordings of saccade were made with a 3 sec time constant, 25 Hz high-cut filter, and digitized with a 3.9 msec sampling time. Four parameters i.e., maximum velocity, gain, latency, and duration, were analyzed. The average (S.D.) of each parameter was 337.1 (65.7) degree/sec, 1.00 (0.14), 199.1 (44.0) msec, and 128.3 (20.2) msec, respectively. We discussed the differences between nasal saccade and temporal saccade. The former was faster than the latter in maximum velocity and shorter in duration, while no differences were recognized in latency. It is suggested that the predominance of nasal saccade in fast eye movement is due to the anatomical difference of the vestibulo-ocular pathway between the medial rectus and the lateral rectus. In other words, because the synaptic inputs to the medial rectus are excitatory as opposed to the inhibitory and excitatory the inputs to the lateral rectus, the difference in muscle tone between the two muscles results in a faster maximum velocity of nasal saccades in fast eye movement.

Adult↗
PubMed1986

A possible split of antigen DQw1 identified by antiserum T3516.

One of the human class II antigens DQw1, which was officially recognized at the 9th International Histocompatibility Workshop in 1984, has a comparatively broad spectrum. One multiparous woman's serum was confirmed to have an antibody which shows a reaction pattern of short DQw1 or a split of DQw1. Our analysis was performed with a population study, two-dimensional gel electrophoresis and blocking experiment by monoclonal antibodies.

Antibodies↗
PubMed1985

Long-term survival of functional hepatocytes from adult rat in the presence of phenobarbital in primary culture.

In the presence of phenobarbital (PB) at 3 mM, hepatocytes isolated from adult rats by a collagenase-perfusion technique survived well on plastic dishes for at least 49 days after initiation of primary culture. PB at concentrations less than 3 mM was ineffective for the maintenance of hepatocytes, and the maintenance of them was attained only in the continuous presence of 3 mM PB. The hepatocytes surviving in the presence of 3 mM PB were morphologically indistinguishable from the hepatocytes after 1-day attachment period, except for the presence of prominent nucleoli in the former. Although both the albumin secretion and tyrosine aminotransferase (TAT) activities of the cells decreased gradually up to day 7 with time in culture, both were thereafter maintained at relatively high levels at least up to day 35 of primary culture. The addition of 10 microM dexamethasone caused a 3-5-fold induction in TAT activity, and the cells were capable of responding to the hormone in this manner at least up to day 28 of primary culture. Furthermore, the cells also had glucose-6-phosphatase activity, even though the level of this enzyme activity was relatively low as compared with that of TAT activity. Survival of hepatocytes in the presence of 3 mM PB was further enhanced by simultaneous addition of dexamethasone (10 microM) and insulin (10 micrograms/ml). The sensitivity of hepatocytes to 3'-methyl-4-dimethylaminoazobenzene (0.24 mM) was remarkably reduced by treatment with PB at 3 mM. PB treatment decreased efficiently the falling rate of total cytochrome P-450 content, but did not induce P-450PB, which is the specific form of cytochrome P-450 induced by PB, in primary cultured hepatocytes. On the other hand, 3-methylcholanthrene (MC, 10 microM) caused an increase of both contents of total cytochrome P-450 and P-450MC, which is the specific form of cytochrome P-450 induced by MC, in primary cultured hepatocytes. However, MC was ineffective for the maintenance of hepatocytes in primary culture. The possible biological actions of PB on primary cultured hepatocytes are discussed on the basis of the experimental data obtained.

Albumins↗
PubMed1985

The effect of pH on alkaline phosphatase activity in serum of the rat and other species.

Contrary to other species, optimum pH of alkaline phosphatase (alk.P.) activity was 9.6 in fed male rats of all age groups studies. In 3- or 6-week-old fasted rats, the optimum pH shifted to 9.8-10.0. This shifting of pH did not occur in 11-week-old rats. Heating to 56 degrees C for 10 min shifted the optimum pH in 3-week-old rats to 9.0, in 6-week-old rats to 9.0-9.4, but no change occurred in 11-week-old rats. In other species (mouse, rabbit, and man), the optimum pH was 10.0-10.2, and was not influenced by fasting or heating.

Adult↗