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Biomedical subjects

T Uchida

Publications and source records attributed to T Uchida.

At least 1,045 records · Page 58Linked to original sources
PubMed1986

Microinjection of partially purified protein factor restores DNA damage specifically in group A of xeroderma pigmentosum cells.

Microinjection of cell extracts prepared from both human placenta and HeLa cells into xeroderma pigmentosum (XP) cells of complementation group A restores unscheduled DNA synthesis (UDS) in these cells after UV irradiation [de Jonge, A., Vermeulen, W., Klein, B. & Hoeijmakers, J. (1983) EMBO J. 2, 637-641]. These cells also showed normal resistance to UV irradiation. The half-life of the factors in the cell extracts corresponding to the UDS activity (factor A) was 14 hr in XP cells of group A, and the maximal level of UDS was exerted 2 hr after microinjection. The factors were sensitive to protease treatment but not to RNase treatment and were found to be approximately equal to 160 and approximately equal to 90 kDa by gel filtration. These two fractions of the factor(s) acted specifically in XP cells of complementation group A among complementation groups A, B, C, D, F, G, and probably E and H.

DNA Repair↗
PubMed1986

Thermophilic HB8 DNA ligase: effects of polyethylene glycols and polyamines on blunt-end ligation of DNA.

NB8 DNA ligase from an extract of Thermus thermophilus HB8 could catalyze blunt-end ligation in the presence of high concentration of polyethylene glycols (PEG) or in the presence of polyamines. In the presence of high molecular weight PEG 20,000, 6,000, or 1,000 (8-28%), the enzyme catalyzed blunt-end intermolecular joining to yield linear oligomers, but no circular DNA forms. But in the presence of low molecular PEG 400, 200 (8-80%), or the monomer, ethylene glycol (16-80%), the circular forms were also detected by intramolecular ligation. In the presence of polyamines, the blunt-end ligation products were linear oligomers and the optimum concentrations were as follows: caldopentamine (0.05 mM), thermine (0.1-0.2 mM), spermine (0.2 mM), thermospermine (0.4 mM), and sperminediol (0.75 mM). Spermidine and putrescine were less capable of producing oligomers. PEG and polyamines elevated the ligation temperature by HB8 DNA ligase. The optimum temperature of blunt-end ligation was about 65 degrees C.

DNA Ligases↗
PubMed1986

Expression of monocytic and T-lymphocytic phenotype in a variant form of acute promyelocytic leukaemia (M3).

A 46-yr-old woman was diagnosed as having M3 variant leukaemia in FAB subclassification with disseminated intravascular coagulation (DIC) and the 15;17 translocation. Immunologic examinations revealed that the blast cells exhibited monocytic (Ia+, Mo1+, Mo2+, My4+, My7+ and My9+) and T-lymphocytic (OKT11+, Leu4+ and Leu5b+) immunophenotype, with probably a biphenotypic population of cells. Expression of monocytic phenotype on the blast cells suggests that M3 variant includes a subtype with monocytic characteristics, and may be related to the morphologic monocyte-like feature of that of M3 variant.

Antibodies, Monoclonal↗
PubMed1986

Immunocytochemical detection of normal and abnormal megakaryocytes using monoclonal antibody to glycoprotein IIb-IIIa (TP80): the quantitative assay in normal and in leukaemic patients.

We identified bone marrow megakaryocytes by an immunocytochemical technique using a monoclonal antibody (TP80) against platelet glycoprotein IIb-IIIa (GPIIb-IIIa). The immunocytochemical technique using TP80, specific to megakaryocytes, enabled us to observe cellular morphology and immunological reaction under light microscopy, and permitted quantitative assessment of megakaryocytes. In normal marrow, TP80 labelled 22 +/- 5 megakaryocytes/10(4) mononuclear cells (mean +/- 1 SD, n = 14). In addition to typical large megakaryocytes, small immature megakaryocytes (less than or equal to 20 micron) were recognized in 10-15% of total megakaryocytes. 4 out of 18 patients with acute myeloblastic leukaemia and 9 of 10 patients with myelodysplastic syndrome showed increased numbers of megakaryocytes. In these patients, cell size distribution was abnormal, i.e., most of the megakaryocytes consisted of small, atypical megakaryocytes. None of the patients with acute lymphoblastic leukaemia showed increased megakaryocytes. Immunocytochemical identification of megakaryocytes using a specific antibody is useful to quantitate the megakaryocytes and to detect the proliferation of atypical megakaryocytes in several leukaemic conditions.

Acute Disease↗
PubMed1986

In vivo evaluation of ethyl cellulose microcapsules containing ampicillin using rabbits, beagle dogs and humans.

Ampicillin, an orally administered antibiotic, was microencapsulated with different viscosity grades of ethyl cellulose (10, 50 and 100 cps EC) and was orally administered to rabbits, beagle dogs and humans. A significant sustained release pattern was observed in rabbits. While a significant decrease in the area under the plasma concentration curve occurred, and the sustained release pattern was not obtained in beagle dogs. In humans, the extent of the sustained release was intermediate between the pattern observed in beagle dogs and rabbits. The treatment of data by log-log plots yielded a linear relation between half lives of dissolution of ampicillin from microcapsules in vitro (T50) and the ratios of pharmacokinetic parameters of microcapsules to those of powder. In order to explain the difference in the sustained release pattern of rabbits, beagle dogs and humans, a pharmacokinetic model, considering gastric-emptying and intestinal-transit rates of drug formulations, was established and the pharmacokinetic consideration was done on the basis of the model. It seems that success in sustained release of a drug depended on the magnitude of the gastric-emptying and intestinal-transit rate constant (kgi) of microcapsules, in the case of a drug with a small absorption rate constant (ka) as observed with ampicillin. The magnitude of kgi was thought to be in the order of beagle dogs, humans and finally rabbits.

Administration, Oral↗
PubMed1986

[Intracavernous injection of etilefrine hydrochloride in iatrogenic priapism].

Intracavernous injection of etilefrine hydrochloride (1 or 2 mg) was performed on four patients with fully erected penis after intracavernous injection of 40 mg of papaverine hydrochloride. One case needed three injections of etilefrine hydrochloride (1 mg), but the erection disappeared in the other three cases within 10 minutes after a single injection of 2 mg of etilefrine hydrochloride. The injection resulted in complete detumescence and relief of the erection in all cases. These observations strongly suggest that the intracavernous injection of etilefrine hydrochloride is effective in treating not only iatrogenic priapism but also priapism due to other etiologies. Also, it might be useful to control erection time after intracavernous injection therapy for impotence.

Adult↗
PubMed1986

[Mitral component of the first heart sound in complete left bundle branch block: the mechanism of the decreased intensity].

To clarify the mechanism of the reduced intensity of the mitral component of the first heart sound (IM) in complete left bundle branch block (LBBB), electrocardiograms, phonocardiograms, apexcardiograms and mitral valve echograms of 12 patients with LBBB (LBBB group) and 13 normal subjects (normal group) were simultaneously recorded. The first derivative of the apexcardiogram was also studied. One of the 12 patients had an intermittent LBBB. There was no significant difference in the P-Q interval between the two groups. The following results were obtained: 1. In the LBBB group; 1) The intensity of the IM, expressed as a ratio of the amplitude of the IM to that of the aortic component of the second heart sound (IIA) on the apical phonocardiograms, was significantly reduced except in one patient who had a relatively short P-Q interval. 2) The timings of the onset of the upstroke of the apexcardiogram and mitral valve closure were significantly and equally delayed. 3) The amplitude of the mitral valve echogram at the onset of the upstroke of the apexcardiogram (end-diastolic amplitude of the mitral valve) was significantly decreased. The closing velocity of the mitral valve was also decreased. 4) The amplitude ratio (H2/H1) and the rate of rise (A) of the apexcardiogram at the onset of the IM were significantly decreased. 2. The intensity of the IM, H2/H1 and A of the apexcardiogram at the onset of the IM were compared for three cases with nearly equal end-diastolic mitral valve amplitudes in each group. The intensity of the IM was apparently reduced in the LBBB group, compared with that of the normal group, and its intensity correlated inversely with H2/H1 and A. These results indicate that the reduced intensity of the IM in LBBB is caused mainly by the decreased amplitude of the mitral valve excursion at the onset of left ventricular contraction. An additional cause is the decreased tension on the closed mitral valve resulting from the slow rate of left ventricular pressure rise at the onset of the IM.

Adult↗