PubMed Health⌕ Search

Biomedical subjects

S Baba

Publications and source records attributed to S Baba.

At least 1,063 records · Page 59Linked to original sources
PubMed1980

[The maintenance of insulin secretory response of long-term cultured pancreatic islets to glucose, acetylcholine and epinephrine (author's transl)].

The present study was performed to investigate whether long-term cultured rat pancreatic islets possess a postcultural insulin secretory response to hormones and neurotransmitters in spite of their lack of stimulation during the culture period. We also investigated the method of maintaining the insulin secretory response of islets cultured in a physiological concentration of glucose. The tissue culture media were TCM 199 supplemented with 5.5 mM glucose (A medium), 5.5 mM glucose plus 1 mM adenosine (B medium), 16.7 mM glucose (C medium), and 16.7 mM glucose plus 1 mM adenosine (D medium). Short-term incubation after the culture period of 14 days showed that the islets cultured in B, C and D media maintained the same insulin secretory responsiveness to 8.3 mM glucose and/or 5 microM acetylcholine and also to 1 microM epinephrine as did non-cultured islets. A similar response was found among the islets maintained in B, C and D media. An insulin secretory response to epinephrine and phentolamine was deficient in islets cultured in A medium, whereas it was maintained in those cultured in C medium. The responsiveness of the islets cultured in C medium to the concomitant stimulation by epinephrine and phentolamine was not different from that of the non-cultured islets. It was thus concluded that the addition of adenosine in the culture medium containing the physiological concentration of glucose was as effective in amintaining the insulin secretory ability of the islets as was the culture medium containing a high concentration of glucose, and it was suggested that even the pancreatic islets cultured in these media, though separated from the innervation might preserve acetylcholine and adrenergic receptors similar to freshly isolated islets. Considering the action of adenosine, the necessity of enhancing ATP and C-AMP concentrations in B cells was also suggested in order to maintain the insulin secretory ability of cultured pancreatic islets.

Acetylcholine↗
PubMed1980

Use of stable isotopes in the study of pharmacokinetics of drugs by mass fragmentography II: Detailed examination of pharmacokinetics of a single oral dose of phenytoin in humans.

To study the pharmacokinetics of phenytoin in detail, a mass fragmentographic method was applied for the precise, sensitive, and specific analysis of phenytoin, 5-(4-hydroxyphenyl)-5-phenylhydantoin, and 5-(4-hydroxyphenyl)-5-phenylhydantoin glucuronide in plasma and urine after administration of a single oral dose of phenytoin to two healthy volunteers. Salivary phenytoin concentrations also were measured. Phenytoin and 5-(4-hydroxyphenyl)-5-phenylhydantoin were analyzed after the addition of deuterium-labeled internal standards and conversion to volatile methyl derivatives for mass fragmentographic analysis. The lower limit of detection was approximately 10 ng/ml. The simultaneous pharmacokinetic analysis of the plasma levels and urinary excretion data of phenytoin and its major metabolite, 5-(4-hydroxyphenyl)-5-phenylhydantoin, yielded detailed information about the pharmacokinetics of phenytoin.

Administration, Oral↗
PubMed1980

A study of cases with partial disappearance of the waves in the auditory brain stem response.

Twenty cases which showed partial loss of ABR waves were reported. Only wave I was recorded in 18 ears tested. Wave I and II; I-III; and I-IV responses were observed in four, eight, and five ears tested, respectively. Cases included pontine glioma (8), acoustic tumor (4), West syndrome (2), leukodystrophy (2), facial neurinoma (1), epidermoid tumor (1), pontine bleeding (1), and unknown cause (1). Fourteen of 20 were tumor cases. This fact indicates that if the ABR shows partial loss of waves, the examiner should first suspect the space-occupying lesions of the brain stem.

Brain Neoplasms↗
PubMed1980

Eccrine poroma.

Explore the source record for details and available documents.

Adenoma, Sweat Gland↗
PubMed1980

Cytochemical studies of nuclear DNA and RNA in normal and abnormal keratinizing tissues.

The distribution patterns of nuclear DNA and RNA in normal and abnormal keratinizing tissues of human skin were examined by electron microscopy, using an enzyme digestion technique. We found that the distribution of nucleic acids in the nuclei of epidermal cells during keratinization changes gradually. In the hair cells, particularly in the cells of hair cortex and Henle's layer of inner root sheath, essentially similar findings were observed. On the other hand, the distribution patterns observed in the tumor cells of calcifying epithelioma and the parakeratotic cells of psoriasis were different from each other and different from the distribution patterns of normal keratinizing tissue, hair, and epidermis. It seems that a similar pattern of reorganization of nucleic acids occurs in the nucleic of normal keratinizing cells as the cells keratinize. However, in abnormal tissue, it seems that the reorganization pattern of nucleic acids in the nuclei is different in each case.

Carcinoma, Squamous Cell↗
PubMed1980

Differentiation between endogenous and exogenous testosterone in human plasma and urine after oral administration of deuterium-labeled testosterone by mass fragmentography.

A mass fragmentographic method employing stable isotopically labeled testosterone was employed to simultaneously determine the concentrations of endogenous and exogenous testosterone in the urine and plasma of two healthy male volunteers. After oral administration of 20 mg testosterone-19,19,19-d3, a slight but significant amount of the deuterated testosterone appeared in the plasma and was rapidly cleared. The results show that the exogenous testosterone did not influence the plasma levels or urinary excretion of endogenous testosterone.

Administration, Oral↗
PubMed1980

Absorption, metabolism, and excretion of oral testosterone in humans by mass fragmentography.

A mass fragmentographic method employing stable isotopically labeled testosterone was employed to follow the time course of urinary excretion of the two main testosterone metabolites, androsterone glucuronide and etiocholanolone glucuronide, in humans after the oral administration of 20 mg testosterone-19.19.19-d3. The results indicate that the extensive metabolism of testosterone in the liver could be the reason that the orally administered testosterone appeared in the circulation only in small amounts, even though testosterone was completely absorbed from the gastrointestinal tract.

Administration, Oral↗