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Biomedical subjects

S Takagi

Publications and source records attributed to S Takagi.

At least 415 records · Page 23Linked to original sources
PubMed1990

Oral supplementation of vitamin K for pregnant women and effects on levels of plasma vitamin K and PIVKA-II in the neonate.

Levels of plasma vitamin K1 (VK1) and vitamin K2 (VK2) and protein-induced vitamin K absence-II (PIVKA-II) were measured in Japanese mothers and their newborn (N = 33). Twenty milligrams of VK1 (N = 11) or VK2 (N = 12) were given orally to randomly selected mothers 7 to 10 days prior to delivery. Means of plasma VK1 and VK2 concentrations were significantly higher in VK1 (p less than 0.01) and VK2 (p less than 0.01) treated mothers than in the controls at delivery, respectively. Similarly, these levels were significantly elevated in cord plasma in VK1 (p less than 0.05) and VK2 (p less than 0.05) treated groups, compared with findings in the control group, although there was a large concentration gradient between maternal and cord plasma (mostly less than one-tenth). A significant positive correlation was found in VK1 concentration between maternal and cord plasma (N = 33, p less than 0.01), and the proportion of PIVKA-II-positive infants was significantly lower in the VK treated groups than in the control group at birth (p less than 0.05). On the fifth postnatal day, mean levels of VK1 (p less than 0.01) and VK2 (p less than 0.01) in breast milk were significantly higher in the VK1 and VK2 treated mothers than in the control mothers, respectively. In the control group, 9 of 10 infants had a positive PIVKA-II, but no one in the treated groups was positive, thereby indicating significant differences between control and treated groups (p less than 0.01 and p less than 0.01, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1990

Cooperative regulation of cytoplasmic streaming and ca fluxes by pfr and photosynthesis in vallisneria mesophyll cells.

In mesophyll cells of Vallisneria gigantea Graebner, Ca(2+) regulates the induction and cessation of cytoplasmic streaming. Streaming is induced when the level of calcium in the cytoplasm is lowered through light-accelerated release of Ca(2+) from the cells (S Takagi, R Nagai [1988] Plant Physiol 88: 228-232). We have now initiated an investigation on the nature of the photoreceptor(s) that are involved in the regulation of Ca(2+) movements across the cell membrane and of streaming. Streaming is induced only when phytochrome exists in the phytochrome-far redabsorbing form (Pfr)-and photosynthesis is allowed to take place for at least 4 minutes. The former effect is typically photoreversible by red and far-red light, and phytochrome is spectro-photometrically detectable in the crude extract from the leaves. The latter effect is assessed in terms of the wavelength dependency and the effects of diuron and atrazine, two inhibitors of photosynthesis. A similar requirement for Pfr and photosynthesis is found to be associated with the acceleration of Ca(2+) efflux in the protoplasts. The results suggest that phytochrome and photosynthetic pigment(s) cooperatively regulate cytoplasmic streaming via modulation of the Ca(2+) transport in the cell membrane.

Journal Article↗
PubMed1990

Supraventricular tachycardia in acquired rubella infection: a case report.

A 6-year-old boy developed supraventricular tachycardia nine days after onset of the exanthem of clinical rubella. The diagnosis of rubella virus infection was confirmed serologically. Except in the neonatal period, only eight cases of cardiac involvement in acquired rubella infection have been previously reported. During epidemics, rubella virus infection should be considered in patients who manifest cardiac symptoms and signs of unknown etiology.

Child↗
PubMed1990

Effects of demethylchlortetracycline phototoxicity on the structure and functions of rat liver mitochondria.

The phototoxic effects of demethylchlortetracycline (DMCT) with UVA radiation on isolated rat liver mitochondria were studied. DMCT at concentration of 21.5 microM with 5.53 x 10(-2) J cm-3 of UVA was found to be a potent uncoupler of oxidative phosphorylation. DMCT alone also uncoupled mitochondria but at higher concentrations (105 microM). ATPase activity was remarkably induced in mitochondria exposed to DMCT (21.5 microM) plus UVA (120% of DNP-stimulated ATPase activity). Content of ATP in such mitochondria when measured after addition of ADP was much smaller than that in control mitochondria. Ultrastructurally, mitochondria treated either with DMCT (21.5 microM) or with UVA alone stayed in the condensed configuration. On the other hand, uncoupled mitochondria treated with DMCT plus UVA became swollen and were changed into the orthodox configuration.

Animals↗
PubMed1990

Thionamides and arsenite inhibit specific T3 binding to the hepatic nuclear receptor.

Methimazole (MMI) and propylthiouracil (PTU) are widely used for the treatment of Graves' disease. However, no studies have been reported on the action of these drugs on binding of L-triiodothyronine (T3) to the nuclear receptor. T3 receptors of rat liver nuclei, prepared by differential centrifugation, were extracted with 0.4 M KCl and 5 mM dithiothreitol (DTT). In the assessment of T3 binding to the DTT-reduced receptor, the hepatic nuclear extract was chromatographed on Superose 6 to remove DTT and isolate proteins of relative mass approximately 50,000 (chromatographed nuclear receptors (CNRs)), prior to the addition of [125I]T3 of high specific activity (3300 microCi/micrograms; 1 Ci = 37 GBq). MMI or PTU at 2 mM reduced specific T3 binding to CNR by 84% and 85%, respectively. The inhibitory effects of these reagents and 2 mM sodium arsenite (which complexes dithiols) were additive. Scatchard analyses indicated that neither MMI nor PTU (at 2 mM) significantly altered the affinity constant (Ka) (from 2.41 x 10(9) to 1.74 x 10(9) M-1 for PTU and 1.79 x 10(9) M-1 for MMI), while they both decreased (p less than 0.02) maximal binding capacity (from 0.36 +/- 0.02 to 0.19 +/- 0.02 pmol/mg protein for MMI and 0.17 +/- 0.02 pmol/mg protein for PTU). Dose-response curves showed that 50% inhibition was attained at 0.6 mM PTU or 1.0 mM MMI with approximately 25% inhibition by both at 0.1 mM. Artefactual binding effects by MMI and PTU on [125I]T3 were excluded by chromatography experiments. Similar results were obtained using nuclear receptors prepared from livers of hyperthyroid rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Enhanced root fluoride uptake by monocalcium phosphate monohydrate gels.

Application of monocalcium phosphate monohydrate (MCPM) gel, which produces small amounts of dicalcium phosphate dihydrate in enamel, was previously shown to increase the enamel reactivity with fluoride (F). This study was conducted to determine whether the MCPM gel treatment is also effective in enhancing F uptake by root surfaces of human teeth. The results show that samples receiving daily treatments with MCPM gel for 10 min followed by immersion in a 1-ppm F solution for 5 days acquired a significantly greater amount of F compared to the controls which had the same exposure to the F solution. Because the F solution was undersaturated with respect to calcium fluoride (CaF2), the F incorporated into the root is apparently apatitic and not CaF2. This experimental treatment should be feasible in the clinical situation since only a short treatment time was required and delivery of the MCPM gel to specific sites was relatively easy.

Calcium Phosphates↗
PubMed1990

Assessment of loosely-bound and firmly-bound fluoride uptake by tooth enamel from topically applied fluoride treatments.

The amounts of loosely-bound fluoride (F) deposited on human enamel by two topical F treatments were measured with use of a constant-composition F washing method. Enamel biopsies conducted before treatment and after the washing were used for determination of the firmly-bound F uptake. The results showed that (1) the washing system did not remove F from untreated enamel surface, (2) a four-minute application of an acidulated phosphate fluoride (APF) gel deposited 27.2 (2.4) (mean, S.E.) micrograms of loosely-bound F per cm2 of enamel surface and 186 (111) ppm of firmly-bound F in the outer 10 microns of enamel, and (3) a four-minute application of a pH-2.1 dicalcium phosphate dihydrate (DCPD)-forming solution followed by APF produced 44.9 (3.1) micrograms/cm2 of loosely-bound F and 1280 (354) ppm of firmly-bound F in the outer 10 microns of enamel. The results showed that the DCPD pre-treatment effectively enhanced the enamel reactivity with F, so that the DCPD-APF treated enamel acquired greater amounts of both loosely-bound F and firmly-bound F than did samples treated with APF alone.

Acidulated Phosphate Fluoride↗
PubMed1990

Setting reactions and compressive strengths of calcium phosphate cements.

Setting reactions and compressive strengths of a self-hardening calcium phosphate cement (CPC) were investigated. The CPC consists of tetracalcium phosphate (TTCP) and anhydrous dicalcium phosphate (DCPA). The cement specimens were prepared by mixing 0.7 g of the powder (TTCP 72.9 wt% + DCPA 27.1 wt%) with 0.175 mL of the liquid (25 mmol/L H3PO4 and 1.32 mmol/L sodium fluoride). The specimens were removed from the molds at pre-determined time intervals after being mixed, and their compressive strengths were measured. Immediately afterward, the fractured specimens were rapidly frozen in ethanol (-80 degrees C), lyophilized, and examined by powder x-ray diffraction and scanning electron microscopy (SEM). The results showed that (1) hydroxyapatite was the only reaction product; (2) the reaction was nearly completed within four h, during which both the reaction product and compressive strength increased linearly with time, resulting in a strong correlation between the two; and (3) fully set CPC consisted primarily of small rod-like crystals and some platy crystals.

Calcium Phosphates↗
PubMed1990

The changes of antioxidative enzyme activities in equine erythrocytes following exercise.

The change in activities of 3 major antioxidative enzymes in equine erythrocytes, superoxide dismutase (SOD), glutathione peroxidase (GSHpx), and catalase, was investigated in order to evaluate the effect of exercise. Blood samples were obtained from 11 thoroughbred horses before and immediately after vigorous exercise which induced the increase of plasma lipid peroxide (Lpx) concentration from 1.16 +/- 0.40 nmol/ml to 1.29 +/- 0.34 nmol/ml. Following the exercise, the GSHpx activity in erythrocytes was significantly reduced from 69 +/- 10 IU/gHb to 65 +/- 8 IU/gHb, whereas SOD and catalase activities were not changed. Effects of an antioxidative compound, containing selenium and vitamin E(Se-E), on the response of antioxidative enzyme activities following the exercise were examined. Seven horses were injected intramuscularly with Se-E(Se:25 mg, vitamin E:54.8 mg) and received the same vigorous exercise. After Se-E treatment, plasma Lpx levels before the exercise were decreased from 1.24 +/- 0.09 nmol/ml to 0.86 +/- 0.03 nmol/ml, however, SOD, GSHpx, and catalase activities were not varied. The Se-E treatment slightly prevented the decrease in GSHpx activity and the increase in plasma Lpx level after the exercise, having no effect on SOD and catalase activities. These results suggested that the changes of GSHpx activity in erythrocytes might reflect the protective condition against exercise-induced lipid peroxidation.

Animals↗
PubMed1990

Chronic toxicity of 2-methyl-4-chlorophenoxyacetic acid (MCPA) in mice.

One of the phenoxy herbicides, 2-methyl-4-chlorophenoxyacetic acid (MCPA) was soaked with pellet dissolved by corn oil and given to ICR male mice for 18 months at levels of 40, 200, 1,000 and 5,000 ppm (about 3.9, 19.0, 95.6 and 566.4 mg/kg/day, respectively). The animals were then placed on a control diet for 12 months. Treatment with 5,000 ppm of MCPA resulted in a significantly decreased survival rate of the mice. Histopathological examination of mice treated with 40 ppm MCPA revealed the occurrence of leukemia which showed neoplastic infiltration in the liver. No adverse effect of the gallbladder, except for papillary proliferation, was noted at all the dose levels of the experimental groups.

2-Methyl-4-chlorophenoxyacetic Acid↗
PubMed1990

Selenium contents in human gallbladder bile.

The selenium contents in human gallbladder bile were analyzed. Thirty-seven subjects were studied; 22 patients with cholelithiasis in Niigata Prefecture and 15 patients (13 with cholelithiasis and 2 with gallbladder polypus) in Kochi Prefecture. Five ml of bile was withdrawn with a syringe from the gallbladder during the operation and stored at -20 degrees C until analysis. For the analysis by gas chromatograph with an electron-capture detector, 0.2 ml of sample was used. The mean selenium contents in bile were 269 +/- 39.0 (mean +/- S.D.) ng/ml for the subjects in Niigata and 285 +/- 84.4 ng/ml in Kochi; without significant difference. Of 37 samples analyzed, the mean content was 276 +/- 61.0 ng/ml.

Adult↗
PubMed1990

HLA antigens in cancer of the gallbladder.

Thirty one patients with gallbladder cancer (GBC) and 32 healthy controls were typed using antisera against 12 HLA-A, 31 HLA-B, 7 HLA-C and 13 HLA-DR antigens. The DR4 frequency of 61.3% (19/31) in GBC was significantly different from that of 28.1% (9/32) in the control (p = 0.00794 by Fisher's exact test). The relative risk and the etiologic fraction were 4.0 and 0.46, respectively.

Adult↗
PubMed1990

Tuberculoma of the cerebellum--case report.

A 25-year-old female presented with a 1-month history of headache and vomiting. Computed tomography revealed several enhanced nodules with surrounding edema in the right cerebellum. A T2-weighted magnetic resonance image showed heterogeneous high signal intensity throughout the right cerebellar hemisphere. A tuberculin skin test was positive and the erythrocyte sedimentation rate was slightly high, but there was no other clinical evidence of a tuberculous process. The histological diagnosis of the surgical specimen was tuberculoma. The combination of surgery and antituberculosis chemotherapy eradicated the cerebellar lesions.

Adult↗
PubMed1990

Structural analyses of sugar chains from ricin A-chain variant.

Two glycopeptides were isolated from a tryptic digest of ricin A-chain variant by gel filtration and reversed-phase HPLC. Their amino acid compositions and sequences showed that Asn-10 and Asn-236 are glycosylated. The sugar chains were liberated from these glycopeptides by hydrazynolysis, N-acetylated, and pyridylaminated. Component analysis and comparison of elution positions of the purified pyridylamino (PA-) sugar chains with those of authentic PA-sugar chains from the major ricin A-chain by reversed-phase HPLC and size fractionation HPLC suggested that both sugar chains linked to Asn-10 and Asn-236 of the ricin A-chain variant are M3FX, identical to that linked to Asn-10 of the major ricin A-chain.

Carbohydrate Conformation↗
PubMed1990

Structures of sugar chains of water-soluble glycoproteins in developing castor bean cotyledons.

The structures of sugar chains from the water-soluble glycoproteins in developing castor beans have been identified. The structural analyses were done by a fluorescence method combined with exoglycosidase digestions and 1H-NMR spectroscopy. The identified structures fell into two categories; one was an oligomannose-type, the other xylomannose-type or xylose-containing type. Among these oligosaccharides, Man3Fuc1Xyl1GlcNAc2 (M3FX; 38%) and Man6GlcNAc2 (M6B; 22%) were the major structures. The higher mannose-content oligosaccharides (Man8-7GlcNAc2) were only 4.1%, and the further-modified structures (GNM3FX, M2FX) than M3FX were 22% of the total.

Carbohydrate Sequence↗
PubMed1990

[Factors of gastric lesions following after transcatheter arterial embolization for primary hepatoma].

To clarify the influence of Transcatheter Arterial Embolization (TAE) on the stomach, endoscopic examination was carried out before and after TAE. Forty-six TAE were performed in 27 patients with primary hepatoma. New gastric lesions, erosions and ulcers, were developed in 25 of 46 TAE. There was no significant relationship between the incidence of the lesions in the cases with esophageal varices (15/24) and the cases without (10/22) and there was no significant relationship between the incidence of the lesions after the first TAE (12/22) and after the second TAE (5/14). Period between the first and the second TAE had no statistical influence on the lesions after the second TAE. Hepatic functions (Child's classification; Rmax, K, R15 of ICG; serum total protein; serum albumin; total bilirubin; prothrombin time; hepaplastin test) before TAE were not statistically related to the appearance of the gastric lesions following TAE (Table 1). On the other hand, the cases which showed apparent effects of TAE including 0.2 time decrease of AFP had the more gastric lesions (P less than 0.05) (Table 2). The cases with upper abdominal pain after TAE had more gastric lesions (24/38) than the cases without (2/8) (P less than 0.05). But the cases undergone TAE with high possibility of the influx of gelatin sponge pieces, lipiodol or anticancer agents into the supplying vessels for the stomach did not exhibit significant incidence of the lesions (Table 3). Thus, when TAE is followed by a 0.2 time decrease in AFP, it is necessary to pay more attention to the gastric lesions. The prophylactic administration of H2 antagonist before or just after TAE did not seem useful to prevent the gastric lesions. These findings suggest that the influx of gelatin sponge pieces, lipiodol or anticancer agents to the stomach does not always cause gastric ulcer or erosion.

Aged↗
PubMed1990

[Clinical study of S 6472 in urinary tract infection].

Clinical studies on S 6472, a longer lasting preparation of cefaclor (CCL), were performed and the following results were obtained. S 6472 was administered orally to 102 patients with urinary tract infections including 16 with acute uncomplicated pyelonephritis, 32 with acute uncomplicated cystitis, 31 with complicated pyelonephritis and 23 with complicated cystitis. 95 patients were treated with 375 mg of S 6472 2 times daily and 7 patients were treated with 750 mg of S 6472 2 times daily. The overall clinical efficacy was evaluated on the basis of the criteria proposed by the Japanese UTI Committee. 1. Clinical efficacies in 11 cases of acute uncomplicated pyelonephritis were excellent in 10 and moderate in 1, with an overall efficacy rate of 100%. Bacteriologically, all 12 strains identified in the acute uncomplicated pyelonephritis cases were eradicated, with an eradication rate of 100%. 2. Clinical efficacies in 21 cases of acute uncomplicated cystitis were excellent in 17, moderate in 3 and poor in 1, with an overall efficacy rate of 95%. As to bacteriological responses, 22 strains identified in the acute uncomplicated cystitis cases (except 1 of Escherichia coli) were eradicated, with an eradication rate of 95%. 3. Clinical responses in 43 cases of complicated urinary tract infections were excellent in 20, moderate in 15 and poor in 8, with an overall efficacy rate of 81%. Bacteriologically, 39 strains, including only one strain of P. aeruginosa, in the complicated urinary tract infection cases (except 4 of E. coli, 1 of Klebsiella pneumoniae, 1 of Enterococcus faecalis and 2 of Enterobacter cloacae) were eradicated, with an eradication rate of 83%. As side effects, slight stomatitis and gastric discomfort were noted in 1 patient each but we were able to continue the medication. Abnormal laboratory test values found were: 1 case of a slight and transient increase of lymphocytes in peripheral blood and 1 case of a slight and transient increase of serum creatinine level.

Administration, Oral↗