Search PubMed⌕ Search

Biomedical subjects

T Ogata

Publications and source records attributed to T Ogata.

At least 451 records · Page 25Linked to original sources
PubMed1984

Structural proteins of Chikungunya virus.

Polyacrylamide gel analysis of the structural proteins of African and Asian strains of Chikungunya virus, an alphavirus, showed that both strains contain three structural proteins: glycosylated E1 and E2, embedded in the viral envelope, and a nonglycosylated nucleocapsid protein. In pulse-chase experiments the precursor protein PE2 was chased into glycoprotein E2, which migrated slightly faster than did glycoprotein E1. The third Chikungunya glycoprotein, E3, was not associated with mature virions but was released into culture fluids. With glycoproteins E1 and E2, separated by glass wool column chromatography, it was shown that hemagglutinating activity is associated with glycoprotein E1.

Chikungunya virus↗
PubMed1984

Scanning electron microscope studies on the Schwann cells in rat motor endplates with special reference to their finger-like projections.

Three-dimensional structures of the Schwann cell in the rat motor endplate were observed by scanning and transmission electron microscopy. A few Schwann cells lodged over the surface of the motor endplates and their nuclear portion swelled roundly. From the Schwann cell body, a few processes extended downwards, divided several times and covered only the upper orifice of the synaptic groove; they did not cover the surface of the protuberances or the ridges of the sarcolemma which separated the synaptic grooves. The lateral sides and ends of the Schwann cell processes were frilled with finger-like projections. They fixed on the surface of the basal lamina of the sarcolemma and sealed the nerve terminals in the synaptic grooves.

Animals↗
PubMed1983

Occurrence of saxitoxin and other toxins in the liver of the pufferfish Takifugu pardalis.

Highly toxic livers of the pufferfish Takifugu pardalis were extracted with acidic ethanol. The toxins extracted were partially purified by chromatography on Bio-Gel P-2 and then Bio-Rex 70, resulting in separation into three fractions I, II and III. ratios of total mouse units per fraction were approximately 0.1:100:0.01, respectively, with tetrodotoxin (TTX) as standard. By TLC, electrophoresis and a TTX analyzer, Fr. II was identified as TTX and, unexpectedly, Fr. III as saxitoxin, while Fr. I remains unidentified.

Animals↗
PubMed1983

Release of tetrodotoxin and paralytic shellfish poison from puffer liver by RNase.

A nontoxic high-molecular fraction was separated from the extracts of toxic liver of a puffer, Takifugu poecilonotus, by Sephadex G-50 gel filtration. This fraction became toxic when digested with RNase T2. The toxins were partially purified by activated charcoal treatment, followed by chromatography on Bio-Gel P-2 and Bio-Rex 70, and were analyzed by TLC and electrophoresis. The results showed that most of the toxicity is accounted for by tetrodotoxin, and the remainder by saxitoxin and other unidentified toxins. The corresponding high-molecular fraction separated from nontoxic liver of another puffer, T. rubripes, did not release any toxin on RNase digestion.

Animals↗
PubMed1983

Myoclonus, cerebellar disorder, neuropathy, mitochondrial myopathy, and ACTH deficiency.

A 50-year-old Japanese woman with action myoclonus, cerebellar signs, neuropathy with axonal degeneration and onion-bulb formation, muscle atrophy with mitochondrial abnormalities, and isolated ACTH deficiency was reported. Her daughter had myoclonus epilepsy and cerebellar ataxia. Neuropathologic findings included atrophy of the dentate and inferior olivary nuclei, Purkinje's cell loss, and demyelination of the posterior columns and spinocerebellar and pyramidal tracts of the spinal cord, besides severe respirator changes. Lafora's bodies were absent. The present case should be included in the entity "myoclonus epilepsy associated with mitochondrial myopathy."

Adrenocorticotropic Hormone↗
PubMed1983

Regulation of lymphocyte responses in cancer patients. I. Study of cell-surface gangliosides by cholera toxin and their induction of impaired activation.

The gangliosides compose a major portion of the surface membrane structure of the lymphocytes and their expression may relate with functional properties of different lymphocyte subpopulations. In the present study, the binding of the ganglioside GM1 to the human peripheral blood mononuclear cells (PBMC) and their effects on the lymphocyte function were examined. Cholera toxin (CT) was used as an indicator for detection of GM1 on the cell surface. It was shown that the exogenous GM1 binds to normal PBMC and inhibits proliferative responses in vitro by various mitogens (Con A, PHA, PWM). It was also revealed that more than 18 h is required to induce unresponsiveness of lymphocytes by preincubation with GM1, even though GM1 bound very rapidly (10-30 min) to lymphocytes. Some intracellular event may be needed to induce unresponsive state of the lymphocytes by GM1 binding. Moreover, the number of CT binding lymphocytes and the amount of CT bound to each cell showed to increase in the cancer patients. These results suggest that the increase of GM1 in the serum and the lymphocyte surface may be one of the mechanisms of suppressed lymphocyte responsiveness in the various pathological states especially in the cancer patients.

G(M1) Ganglioside↗