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Biomedical subjects

T Takeuchi

Publications and source records attributed to T Takeuchi.

At least 1,603 records · Page 89Linked to original sources
PubMed1986

Effect of thyrotropin on conversion of T4 to T3 in perfused rat liver.

The present study was undertaken to elucidate the direct effect of thyrotropin (TSH) on the conversion of thyroxine (T4) to 3,5,3'-triiodothyronine (T3) in the isolated perfused rat liver. The liver was perfused without recirculation with a synthetic medium containing 10 micrograms/dl T4 and the effect of constant infusion of bovine TSH (125 or 250 microU/ml) on the conversion of T4 to T3 was examined. T4 uptake in the perfused liver was not changed by the addition of TSH. The release of T3 (10.3 +/- 1.4 ng/g/30min, mean +/- SD), tissue T3 production (99.5 +/- 21.4 ng/g/30min), net T3 production (102.6 +/- 20.2 ng/g/30min), and the conversion rate of T4 to T3 (14.8 +/- 3.5%) in the liver perfused with 250 microU/ml TSH were significantly higher than those in controls (8.1 +/- 1.2 ng/g/30min, 69.0 +/- 6.8 ng/g/30min, 69.9 +/- 6.1 ng/g/30min, and 10.0 +/- 0.8%), respectively. These results suggest that TSH may directly enhance hepatic conversion of T4 to T3 in rats in vitro.

Animals↗
PubMed1986

Direct coupling of micro high-performance liquid chromatography with fast atom bombardment mass spectrometry. II. Application to gradient elution of bile acids.

A new system without a moving belt has been developed for direct coupling of micro high-performance liquid chromatography with fast atom (xenon or argon) bombardment mass spectrometry. The structure of the interface was basically the same as used previously, but the mass spectrometer was modified by adding both a liquid nitrogen trap between the ion source housing and the diffusion pump, and a position adjuster for the interface. Stable ionization of the solute in a glycerol matrix is achieved at flow-rates below 2 microliter/min. The system was applied to the analysis of bile acids by gradient elution chromatography. Steady baselines were observed in the mass chromatograms.

Bile Acids and Salts↗
PubMed1986

[Evaluation of the dopaminergic neuroendocrine control of prolactin release during labor in humans].

Eight women with normal term pregnancy were i.v. administered 10 mg Metoclopramide (M), dopamine antagonist, before and during labor. Serum prolactin (PRL), TSH, GH and cortisol levels were measured at -30, 0, 30 and 60 minutes after M administration by specific radioimmunoassay. Basal serum PRL levels before labor, 287.5 +/- 28.6 ng/ml (mean +/- S.E.), significantly declined during labor to 237.0 +/- 22.4 and 216.4 +/- 22.9 ng/ml (p less than 0.05 at both) at 0 and 30 minutes before M administration, respectively. The increments in serum PRL at 30 and 60 minutes after M administration during labor (209.5 +/- 33.9 and 120.0 +/- 27.1 ng/ml, respectively) were not significantly different from those before labor (202.1 +/- 48.7 and 89.9 +/- 30.1 ng/ml, respectively), suggesting that the decline in serum PRL levels during labor is not due to the dopaminergic control. Basal serum TSH and GH levels were not significantly changed by labor and M administration either before or during labor. Serum cortisol levels tended to increase during labor, but these changes were not significant. The data suggest that the PRL releases from the pituitary during labor are not controlled by the dopaminergic mechanism.

Adult↗
PubMed1986

DNA-daunorubicin complexes specifically suppress in vitro spontaneous anti-DNA antibody production in lymphocytes of patients with systemic lupus erythematosus.

Elevated production of anti-DNA antibody in patients with systemic lupus erythematosus (SLE) is a central problem in the pathogenesis of tissue injury. In the present study, we attempted to manipulate anti-DNA antibody production through the antigen-cytotoxic drug conjugates, DNA-daunorubicin complexes. The effect of DNA-daunorubicin complexes was determined by examining SLE lymphocytes for spontaneous in vitro production of anti-DNA antibody. These complexes, at 2 micrograms/ml, suppressed anti-DNA antibody production, but not total IgG production, which suggests that specific suppression of anti-DNA antibody production was achieved at this concentration. We believe that the DNA-daunorubicin complexes affected mainly B cells, since such suppression was obtained by treating B cells, as well as B plus T cells. Furthermore, the complexes had no effect on the proliferative responses of SLE T cells to DNA, phytohemagglutinin, or concanavalin A. These results indicate that DNA-daunorubicin complexes may have the potential for selectively suppressing anti-DNA antibody production in patients with SLE.

Antibodies, Antinuclear↗
PubMed1986

Effects of the lethal yellow (Ay) and recessive yellow (e) genes on the population of epidermal melanocytes in newborn mice.

Very few melanocytes can be detected by the DOPA reaction in the dorsal epidermis of newborn lethal yellow mice (Ay/a). Nevertheless, the epidermis contains a considerable number of melanoblasts (cells positive for the combined DOPA-premelanin reaction). On the other hand, numerous melanocytes as well as melanoblasts are found in the dorsal epidermis of black mice (a/a). The number of epidermal melanoblasts is smaller in (Ay/a than in a/a mice even though the same number of melanocytes is found in the dermis of these animals. It seems probable that the product of the A y gene suppresses either the differentiation or the proliferation of epidermal melanoblasts. The number of melanoblasts plus melanocytes in day-17 embryos from a cross between Ay/a and a/a mice shows a bimodal distribution. It seems possible that half of the embryos were Ay/a and possessed a reduced number of melanoblasts and melanocytes. This result seems to suggest that the Ay gene is active at this embryonic stage. In contrast to the case for the epidermis from Ay/a mice, numerous DOPA-positive melanocytes were detected in the epidermis from e/e mice. However, the total number of melanoblasts plus melanocytes in e/e epidermis did not differ from that in Ay/a epidermis, suggesting that the mode of action of the e gene in the epidermis is different from that of the Ay gene.

Animals↗
PubMed1986

Treatment of childhood acute lymphoblastic leukemia with intermediate-dose cytosine arabinoside and adriamycin.

Eight pediatric patients with acute lymphoblastic leukemia (ALL) were treated with intermediate-dose cytosine arabinoside (ID-AraC, 1 g/m2) in combination with adriamycin except one patient. Of the eight patients, four refractory to the initial induction therapy and one in bone marrow relapse gained complete remission with two to three cycles of this therapy. Four of the five patients have been in continuous remission for 4 to 24 months with the maintenance therapy of monthly administration of ID-AraC. One patient in central nervous system (CNS) relapse has continued in remission from CNS leukemia after two cycles of the therapy. Side effects of ID-AraC and adriamycin were generally mild to moderate and tolerable in all children. These results suggest that the use of ID-AraC and adriamycin might prove effective in the treatment of ALL refractory to other regimens.

Adolescent↗
PubMed1986

Clinical evaluation of gamma-seminoprotein in prostate cancer.

Gamma-seminoprotein (gamma-Sm), a potential new marker for prostate cancer, has been evaluated with a sandwich-type enzyme immunoassay (EIA). This assay system has been confirmed to have a sensitivity and detectable range of 3.0 and 3.0-100 ng/ml, respectively, with a high reproducibility (approximately equal to 6% coefficient of variation between assays). A total of 256 serum samples were drawn from normal Japanese subjects for detection of gamma-Sm. Serum gamma-Sm was undetectable (less than 3.0 ng/ml) in 26 samples from 26 females. In 230 male cases, serum gamma-Sm levels ranged from less than 3.0 to 4.0 ng/ml. These values were not related to age. An upper normal limit of 3.6 ng/ml was calculated for 99 percentile Japanese males (n = 103) over 50 years of age. Serum gamma-Sm was detected in 192 untreated male patients with urological diseases. Gamma Sm levels (mean +/- SD) in each disease were as follows: prostate cancer (n = 64) 11.0 +/- 17.9 ng/ml; benign prostatic hypertrophy (n = 50), 3.02 +/- 0.113; bladder cancer (n = 58), 3.13 +/- 0.514; and renal adenocarcinoma (n = 30), 3.26 +/- 1.01. Serum gamma-Sm levels were statistically higher (p less than 0.05) in the prostate cancer group, however, there was no statistical difference in gamma-Sm levels among clinical stages or histopathologic grades. Furthermore, serum gamma-Sm values showed no correlation (r = 0.3870) with prostatic acid phosphatase (PAP), but were slightly correlated to prostate antigen (PA) levels (r = 0.6980) in patients with prostate cancer. These results suggest that gamma-Sm is a potential tumor marker of prostate cancer and that serially detected serum gamma-Sm levels could be used to monitor the disease.

Adenocarcinoma↗
PubMed1986

Evaluation of two equivalent regimens (BID, QID) of cimetidine to raise intragastric pH over a 24-hour period in patients with duodenal ulcer.

We evaluated two equivalent regimens of cimetidine to raise intragastric pH over a 24-hr period, using a glass pH electrode in five patients with duodenal ulcer. Each patient received the following drug in a randomized fashion: cimetidine 200 mg after each meal and at bedtime (200 mg qid), cimetidine 400 mg after breakfast and at bedtime (400 mg bid), or placebo tablets (control). Mean intragastric acidity for 24 hr was suppressed by 44.0% in 200 mg qid, and by 73.7% in 400 mg bid of control. In particular, nocturnal gastric acidity was suppressed by 63.1% and 91.3% in 200 mg qid and 400 mg bid, respectively. Thus, 400 mg bid was more effective in lowering gastric acidity than 200 mg qid, although the total daily dose of cimetidine in the two regimens was the same.

Adult↗
PubMed1986

Release of cholecystokinin and exocrine pancreatic secretion in response to an elemental diet in human subjects.

We investigated in human volunteers the effects of an elemental diet (ED) containing amino acids on release of endogenous cholecystokinin (CCK) using a highly sensitive and specific radioimmunoassay of CCK and exocrine pancreatic secretion using a dye dilution technique with polyethylene glycol 4000 as a nonabsorbable marker. Intrajejunal administration of ED at three different infusion rates (12.5, 25, and 50 ml/30 min) resulted in a significant increase in plasma CCK concentration in a dose-related manner. Plasma concentrations of gastrin or secretin, however, did not change. Pancreatic secretion of protein, amylase, and bicarbonate also increased significantly. The change in pancreatic secretion of protein, amylase, and bicarbonate output paralleled that of the circulating CCK level but not that of plasma secretin. Thus, the dose of amino acid contained in ED recommended for clinical use can significantly stimulate the release of CCK from the upper small intestine, raising the plasma concentration of CCK. This level can evoke a significant increase in exocrine pancreatic secretion.

Adult↗
PubMed1986

Comparison of fatty acids and lipids of smolting hatchery-fed and wild Atlantic salmon Salmo salar.

In Atlantic Canada the Atlantic salmon Salmo salar change from the parr stage to the smolt stage while still in fresh water, preparatory to migration to salt water. In some stocks this takes place during the second overwintering. In several hatcheries where the water temperature drops to 0-0.5 C and the ponds ice over, there is a high incidence of erosion of the dorsal and pectoral fins and sometimes of the caudal fin. No disease organism has been identified, and the lesions heal over in most cases. Dietary fatty acids were thought to be a factor. A detailed study of lipid recoveries and classes has shown that in the skins of abnormal fish the total lipid is 7.8% compared to 4.7% in control fish. Unexpectedly, an analysis of one lot of healthy smoltstage wild fish showed that whole bodies have only a quarter of the lipid of comparable hatchery fish. Comparison of fatty acids showed that wild fish lipids include a higher proportion of arachidonic acid than those of the hatchery fish. In the latter, linoleic acid is provided readily by diet but the elongation to arachidonic acid evidently does not proceed. These results suggest that the smolt lipid is involved intimately with either the cause of the dermal lesion or is a defense mechanism, possibly mediated through oxygenase activity.

Aging↗
PubMed1986

Effects of cyclic nucleotides, betazole hydrochloride and acetylcholine on pepsinogen secretion from isolated rabbit gastric mucosa.

The effects of dibutyryl cyclic AMP (db-cAMP), dibutyryl cyclic GMP (db-cGMP), betazole hydrochloride (betazole) and acetylcholine (ach.) on pepsinogen secretion from isolated rabbit gastric mucosa were studied using an organ culture system. The 10(-3) M db-cAMP, but not db-cGMP of any concentration, produced a significant enhancement of pepsinogen secretion into the culture medium. In the presence of aminophylline (phosphodiesterase inhibitor), betazole stimulated pepsinogen secretion at concentrations of 10(-8), 10(-6) and 10(-4) M. The 10(-4) M betazole stimulated pepsinogen secretion most strongly (208% of control) and 10(-6) M betazole induced submaximal secretion (137% of control). Ach. stimulated pepsinogen secretion at 10(-8), 10(-6), 10(-4) and 10(-2) M. The peak secretion occurred at 10(-4) M ach. (303% of control). Betazole (with aminophylline) against a background of 10(-6) M ach. (submaximal stimulation dose), produced an intense stimulation of pepsinogen secretion at the concentrations of 10(-8), 10(-6) and 10(-4) M, and the secretion rate expressed as percent of control were 277, 350 and 329%, respectively. These responses were not considered the additive action by betazole and ach. but the potential interaction between the two agents in pepsinogen secretion. From these findings, we conclude that betazole-ach. interdependency exists in in vitro pepsinogen secretion.

Acetylcholine↗
PubMed1986

Delta and spindle components in compressed spectral array during nocturnal sleep in infants with cerebral palsy.

The correlations between the delta and spindle components in compressed spectral array in 21 mentally retarded children with cerebral palsy (CP) (from 4 months to 5 years of age) and 32 reference mentally retarded children of no abnormality with the exception of psychomotor retardation (from 4 months to 12 years of age) were studied throughout nocturnal sleep. In 11 (52%) out of 21 CP cases and 27 (84%) out of 32 reference cases, periodic changes of delta and spindle rhythm powers were noted in sleep EEG (group A). In 5 (24%) other cases in CP and 5 (16%) reference cases delta but not spindle rhythm powers were found (group B), and in the remaining 5 (24%) CP cases neither delta nor spindle rhythm powers were found throughout nocturnal sleep (groups C). A significant decrease in the developmental quotient (DQ) was found in group C as compared with group A in both CP and reference cases. Moreover, a significant decrease in DQ was also found in group B as compared with group A of reference cases.

Cerebral Palsy↗
PubMed1986

Do protozoa conceal a high potency of nucleoside triphosphate hydrolysis present in Toxoplasma gondii?

ATP hydrolytic activity in whole cell homogenates of some protozoa was assayed in the presence or absence of dithiothreitol. The activities in all protozoan cell homogenates, except Toxoplasma gondii, ranged from 0.6 to 32 mumol/mg protein/hr, irrespective of the presence or absence of dithiothreitol. A remarkably higher activity, 11,690 mumol/mg protein/hr, was observed for T. gondii in the presence of dithiothreitol. These results indicate that the higher ATP hydrolytic potency observed for T. gondii is not universal to protozoa, rather it is unique to T. gondii.

Adenosine Triphosphate↗
PubMed1986

Serum and urinary carnitine and organic acids in Reye syndrome and Reye-like syndrome.

Free and acyl-carnitine in serum and urine, and urinary organic acids were measured in 6 patients with Reye syndrome and Reye-like syndrome. The free and total carnitine concentrations were significantly reduced in serum during the acute phases of the diseases. Thus, the ratio of acylcarnitine to free carnitine was significantly increased. Urinary excretion of acylcarnitine was greatly increased, and the acylcarnitine to total carnitine ratio was therefore greater than in controls. The urinary organic acids comprised large amounts of lactic acid, dicarboxylic acids and ketone bodies. It is suggested that carnitine deficiency is induced as more carnitine is consumed to buffer the increased amount of toxic acyl-CoA compounds metabolized from free fatty acids and the many organic acids. These results indicate that administration of L-carnitine should generally be considered in patients with Reye syndrome and Reye-like syndrome.

Acids↗
PubMed1986

Quantitative analysis of mouse tyrosinase by enzyme-linked immunosorbent assay.

A sensitive, specific, competitive enzyme-linked immunosorbent assay (ELISA) was developed for quantitative analysis of tyrosinase. Binding sites of anti-tyrosinase antibodies were competed for by purified tyrosinase adsorbed onto microtiter plates and a known (standard) or unknown (sample) amount of tyrosinase in solution. Adsorbed antibodies were detected by goat anti-rabbit IgG F(ab')2 labeled with peroxidase. A sensitivity range of 2.1 to 14 ng (30-200 fmol)/well was obtained. SDS was found to be the most suitable detergent for solubilizing the enzyme. Tyrosinase was extracted from B16 mouse melanoma and assayed by the ELISA. The tyrosinase content per mg melanoma protein was 505 +/- 106 (S.D.) ng. This assay is not only useful for measuring the content of normal tyrosinase in crude extracts but also is possibly applicable to detecting the unprocessed tyrosinases.

Animals↗
PubMed1986

Effect of licorice extract (Fm100) on release of secretin and exocrine pancreatic secretion in humans.

We investigated the effect of a fraction of licorice extract (Fm100) on release of endogenous secretin in seven human volunteers using radioimmunoassay and exocrine pancreatic secretion using a dye dilution technique with polyethylene glycol 4000 as a non-absorbable marker. Intrajejunal administration of Fm100 (pH 6.5) in three different doses (200, 400, and 800 mg/30 min) resulted in significant increases in both plasma secretin concentration and pancreatic bicarbonate output in a dose-dependent manner (r = 0.737, p less than 0.001, and r = 0.483, p less than 0.01, respectively). However, it did not influence pancreatic secretion of protein or amylase. The correlation between plasma secretin concentrations and bicarbonate outputs was also significant (r = 0.483; p less than 0.01). These results indicate that endogenous secretin is released by Fm100 in humans and suggest strongly that the increased pancreatic bicarbonate secretion is attributable to the increased plasma concentration of secretin.

Adult↗
PubMed1986

Direct demonstration of immunoregulatory T-cell defects in patients with systemic lupus erythematosus.

The present study was undertaken to determine directly whether immunoregulatory T cells have a defective suppressor function in patients with systemic lupus erythematosus (SLE), and whether anti-T-cell antibodies are essential for immunoregulatory T-cell defects. Peripheral blood T cells and T-cell subsets were determined in 52 SLE patients. The ratio of T4 to T8 cells was distributed over a wider range in patients with SLE than in the controls. Patients with SLE were divided into three groups (low, normal and high) by the T4/T8 ratio. Lymphocytes from 12 SLE patients (7 with low and 5 with high T4/T8 ratios) were studied extensively. Their disease was inactive or in remission. Anti-T-cell antibodies were not detected, and yet the patients had immunological abnormalities characterized by the presence of antinuclear antibodies and hypergammaglobulinaemia. The SLE patients with high T4/T8 ratios had a decreased number of T8 cells, and defective suppressor-effector cells. In contrast, patients with low T4/T8 ratios had decreased T4 cells and/or increased T8 cells, and defective suppressor-inducer cells. Two patients with low T4/T8 ratios had both suppressor-effector and suppressor-inducer cell defects. These results indicate that immunoregulatory circuits in SLE patients are heterogeneous and that immunoregulatory defects exist even when the disease is inactive or in remission. Anti-T-cell antibodies were not essential for such immunoregulatory defects. Thus, immunoregulatory T-cell defects and the development of SLE may be independent conditions due to other unknown causes.

Adult↗