Search PubMed⌕ Search

Biomedical subjects

H Terada

Publications and source records attributed to H Terada.

At least 253 records · Page 14Linked to original sources

Effect of lard and corn oil intake on serum lipids in young men.

An experimental diet with lard (30 g/day for 7 days) and corn oil (30 g/day for 7 days) on high carbohydrate (basal diet) was given to four healthy Japanese young men and the effect of diets containing different fat on serum lipids was examined. Serum total cholesterol was increased significantly from a basal diet of 106 +/- 23 to 141 +/- 26 mg/dl on lard diet, and then decreased significantly (p less than 0.05) to 111 +/- 22 mg/dl on corn oil diet. Serum triglycerides increased significantly (p less than 0.01) from 66 +/- 38 to 173 +/- 32 mg/dl on basal diet. Serum HDL-cholesterol was decreased significantly (p less than 0.01) from 41.9 +/- 1.6 to 31.2 +/- 3.8 mg/dl on lard diet and increased significantly (p less than 0.05) to 41.9 +/- 4.6 mg/dl on corn oil diet. Serum HDL-cholesterol fraction was decreased significantly (p less than 0.01) from 41.6 +/- 4.9 to 28.1 +/- 3.2% on basal diets, but increased significantly (p less than 0.05) to 44.3 +/- 3.1% on lard diet, and then decreased to 36.3 +/- 2.5% on corn oil diet. Serum HDL phospholipid fraction decreased significantly (p less than 0.05) from 62.5 +/- 6.7 to 50.7 +/- 1.8% on basal diet and increased significantly (p less than 0.05) to 60.4 +/- 1.0% on lard and corn oil diet. Serum phospholipids did not change by experimental diets. It is concluded that lard and corn oil have different and specific roles in lipid metabolism.

Adult↗

[Neutrophil dysfunction in chronic neutrophilic leukemia without rearrangements of bcr and immunoglobulin heavy chain genes].

A 67-year-old man was admitted to our hospital with abdominal distension due to hepatosplenomegaly. The peripheral blood revealed Hb content 6.5 g/dl, platelet count 4.7 x 10(4)/microliter, and WBC count 105.8 x 10(3)/microliter with 88% of mature neutrophils. The neutrophil alkaline phosphatase score was 421. Bone marrow aspiration revealed hypercellularity with increased megakaryocytes and myeloid hyperplasia. 46, XY, del 20(q 11) without Philadelphia chromosome was identified by cytogenetic study. The patient was diagnosed as having chronic neutrophilic leukemia and was successfully treated with busulfan, but he died of atypical mycobacteriosis about 20 months later. Analysis of neutrophil function demonstrated diminution of deformability, random mobility, and chemotaxis, but almost normal phagocytosis and bactericidal capacity. Southern analysis showed no rearrangements of breakpoint cluster region (bcr) gene and immunoglobulin heavy chain gene.

Aged↗

[ATP and ADP of platelets in chronic myeloproliferative disorders and multiple myeloma].

The content of platelet adenine nucleotide in chronic myeloproliferative disorders (CMPD) and multiple myeloma (MM) was measured by a luciferin-luciferase method by Holmsen and Weiss. The release of ATP and ADP from platelet during aggregation induced by collagen and epinephrine were analyzed. The total 42 investigated cases consisted of 11 cases of polycythemia vera (PV), 7 cases of essential thrombocythemia (ET), 7 cases of chronic myeloid leukemia (CML), 9 cases of blastic crisis of CML (BC-CML), and 8 cases of multiple myeloma (MM). The healthy control was 19 cases. In CMPD and MM, the amount of ATP was normal in spite of decrease of ADP; therefore, the ratio of ATP/ADP increased. On the other hand, the ATP significantly increased in BC-CML. MM revealed a remarkable increase of ATP release due to the aggregation by collagen and epinephrine. The maximal rate of aggregation of collagen and epinephrine using Lumi-aggregometer indicated a positive relationship with the ATP release by the Holmsen and Weiss' method. The platelet volume in CMPD increased showing correlation with ATP content and not with ADP. In conclusion, CMPD and MM are regarded as acquired qualitative disorders of platelets or secondary storage pool diseases from the view points of the abnormalities in ATP, ADP contents and their release. However, BC-CML and MM revealed some different change from that of CMPD.

Adenosine Diphosphate↗

Structural requirements of salicylanilides for uncoupling activity in mitochondria: quantitative analysis of structure-uncoupling relationships.

The uncoupling activities of more than 20 salicylanilides were measured in rat liver mitochondria. The activities, expressed as the minimum concentrations required for full release of state-4 respiration, ranged over three orders of magnitude. The acid dissociation constant, pKA, and the partition coefficient between octanol and water (Poct) of some of the salicylanilides were determined. These two parameters were found to be well expressed in terms of the Hammett constant, sigma, and the hydrophobic substituent coefficient, II, respectively. The pKA and log Poct values of all the salicylanilides were predicted according to these relationships. Furthermore, the capacity factor, k', on high-performance liquid chromatography was determined on glyceryl-coated-controlled pore glass (gly-CPG). Values of log k' correlated well with those of log Poct. The uncoupling activities of the salicylanilides were analyzed in terms of these three parameters. Both hydrophobic and electron-withdrawing properties were found to be essential for induction of potent uncoupling activity. The correlations using log k' were better than those using log Poct.

Animals↗

A sigmoidal relationship between liver stearoyl CoA desaturase activity and serum hormone concentrations caused by streptozocin and its antagonists.

Stearoyl CoA desaturase activity in liver microsomes, and insulin, thyroxine, and triiodothyronine levels in serum were measured after administration of streptozocin (STZ) and its antagonists to rats. The effect of STZ, which caused hyperglycemia and inhibited the desaturase activity, was antagonized by 2-desoxyglucose and 3-O-methyl-glucose; 1-O-methyl-3-desoxyglucose and 1-O-methyl-3-O-methylglucose were without any effect. The enzyme activity plotted against insulin levels showed a broad sigmoidal curve, whereas the activities versus thyroid hormone levels showed steeper sigmoidal curves.

Animals↗

Effect of arylidene-cyclopentenedione radiosensitizers on ATP synthesis in mitochondria: action as potent inhibitors of phosphate transport.

The effects of the arylidene-cyclopentenedione radiosensitizers, KIH-200, 201 and 202 on ATP synthesis in mitochondria were examined. In spite of the close similarity of their chemical structure to that of the most potent known weakly acidic uncoupler, SF 6847, they did not show any uncoupling activity at concentrations of up to 50 microM. However, these three compounds were found to have very potent inhibitory effects on Pi-transport into mitochondria, all causing 50% inhibition (I50%) at about 7 microM. Thus they are much more potent than the commonly used Pi-transport inhibitors N-ethylmaleimide (I50% = about 40 microM), and mersalyl (I50% = about 30 microM). They may act as SH-reagents, and inhibit Pi-transport by modifying an SH-group(s) in the Pi-transporter.

Adenosine Triphosphate↗

Unique action of a modified weakly acidic uncoupler without an acidic group, methylated SF 6847, as an inhibitor of oxidative phosphorylation with no uncoupling activity: possible identity of uncoupler binding protein.

The potent weakly acidic uncoupler SF 6847 was modified by methylation of its phenolic OH group, and the effect of the resulting derivative, with no acid-dissociable group, on oxidative phosphorylation in rat liver mitochondria was examined. The methylated SF 6847 did not induce uncoupling at up to 40 microM, while SF 6847 uncoupled oxidative phosphorylation completely at about 20 nM, indicating that the acid-dissociable group is essential for uncoupling. The O-methylated SF 6847 at 20 microM did, however, inhibit state 3 respiration of mitochondria, although it did not inhibit electron-flow through the respiratory chain, ATPase activated by weakly acidic uncouplers or Pi-ATP exchange. At the same concentration, it also inhibited ATP synthesis in submitochondrial particles. These features are different from those of known inhibitors of oxidative phosphorylation. Thus, O-methylated SF 6847 is a unique inhibitor of oxidative phosphorylation. The possible identity of the uncoupler binding protein is discussed on the basis of these results.

Adenosine Triphosphate↗

Quantitative assessment of cerebral blood flow using technetium-99m-hexamethyl-propyleneamine oxime: Part I, Design of a mathematical model.

To design a mathematical model for quantifying cerebral blood flow using 99mTc-hexamethyl-propyleneamine oxime (HM-PAO), basic studies were performed in animals and human volunteers. Microautoradiography revealed that HM-PAO crossed the blood-brain barrier. Thin layer chromatographic studies demonstrated the rapid disappearance of free HM-PAO in the brain tissue. Back diffusion from brain to blood was found negligible. From these observations, the familiar microsphere model was employed in the measurements of blood flow with HM-PAO. This, however, resulted in much lower flow values than simultaneously obtained values with the labeled microspheres. This underestimation was ascribed to the high affinity of HM-PAO to blood cells and serum protein. Taking the binding of HM-PAO to blood components into consideration, the following model equation was designed for quantifying cerebral blood flow: Ce(t) = Ca(t)-kCa(t)*exp(-kt), Cb(T) = F integral of T0 Ce(t)dt, where Ce and Ca are the free HM-PAO concentration in the intravascular space and the arterial whole-blood concentration of HM-PAO, respectively, as a function of time (t), Cb is the brain activity concentration, k is the rate constant for the binding of HM-PAO to the blood components, F is the blood flow value, T is time of measurement, and * denotes the operation of convolution. In clinical studies, Ca(t) and Cb(T) are obtainable from a dynamic single photon emission computerized tomographic study of the brain and multiple arterial blood sampling, respectively. The values for F and k can be estimated using a nonlinear least squares fitting method.

Animals↗

Genetic analysis of developmental mechanisms in hydra. XVIII. Mechanism for elimination of the interstitial cell lineage in the mutant strain Sf-1.

The interstitial cell lineage in mutant strain sf-1 of hydra is temperature sensitive and is lost rapidly from tissue when the animal is cultured at a restrictive temperature of 23 degrees C or higher. The mechanism responsible for this cell elimination process was investigated. Sf-1 polyps were treated at a restrictive temperature of 27 degrees C for varying lengths of time, their tissues were macerated, and the resultant dissociated cells were examined for evidence of phagocytosis after Feulgen staining. It was found that large phagocytic vacuoles were present in the cytoplasm of some epithelial cells. These vacuoles contained partially degraded cells, whose nuclei had highly-condensed and intensely Feulgen-positive chromatin granules. This indicated that, as in colchicine-treated (Campbell, 1976) or starved (Bosch and David, 1984) wild-type hydra, the epithelial cells in strain sf-1 engulfed and disintegrated other cells in the phagocytic vacuoles. The incidence of phagocytosis was higher in sf-1 tissue maintained at elevated temperature than in sf-1 tissue maintained at normal temperature. However, the observed incidence was relatively low (maximally 0.14 phagocytosed cells per epithelial cell) and appeared to be too low to account for the very rapid interstitial cell loss occurring in this strain. We concluded that elimination of the interstitial cell lineage at a restrictive temperature in strain sf-1 takes place in part by phagocytosis and in part by other yet-unidentified mechanisms (cf., Marcum et al., 1980).

Animals↗

Electrical oscillation and fluctuation in phospholipid membranes. Phospholipids can form a channel without protein.

Fluctuations and/or step-wise changes in membrane potential and electrical current were observed in bilayer membranes of dioleoylphosphatidylcholine (DOPC) in the absence of any channel protein. The DOPC membranes consisted of three types: black lipid membranes, pipette-clamp membranes and lipid membranes transferred to porous filter paper by conventional Langmuir-Blodgett techniques. This finding is significant since phospholipids are the main constituents of biomembranes. Lipid molecules with a cis double bond in their carbon skeleton are suggested to be important in the gating or excitation of biomembranes.

Electric Conductivity↗

Determination of flow and rate constants in a kinetic model of [99mTc]-hexamethyl-propylene amine oxime in the human brain.

The values for flow and rate constants for a kinetic model of [99mTc]-hexamethylpropyleneamine oxime (HM-PAO) distribution in the human brain were determined. The single-pass extraction ratio of HM-PAO was also determined in the rat brain by the indicator diffusion method; a value of 0.90 +/- 0.02 (mean +/- SEM, n = 5) was obtained. Time course data of brain activity and arterial blood activity of the tracer were fitted to a four compartment model: Values of blood flow and the first-order rate constants for backdiffusion of the diffusible tracer from brain to blood (k2), conversion of the lipophilic tracer to the hydrophilic one in brain (k3), and conversion of the diffusible tracer to the nondiffusible one in blood (k5) were determined. Conversion of hydrophilic tracer back to a lipophilic form in both blood and brain was assumed to be negligible during the course of the experiment. The values obtained for blood flow, k2, and k3 were, respectively, 0.40 +/- 0.03 ml/g/min, 0.38 +/- 0.04 min-1, and 0.92 +/- 0.05 min-1 in the gray matter (n = 4), and 0.23 +/- 0.01 ml/g/min, 0.17 +/- 0.01 min-1, and 1.01 +/- 0.05 min-1 in the white matter (n = 2) in patients with cerebrovascular disorder. The k5 value was 1.14 +/- 0.06 min-1 (n = 4). These experimentally determined values agree well with the theoretical ones previously reported by Lassen et al. The results suggest the relative constancy of the k3 and k5 values and the more prominent initial backdiffusion of the lipophilic HM-PAO from brain to blood in high flow regions compared to low flow regions.

Animals↗

Direct autoradiographic comparison of 99Tcm-HMPAO with 125I-IMP in experimental brain ischaemia.

Local cerebral blood flow (LCBF) images of HMPAO and IMP were directly compared in experimental brain ischaemia in the same rats using a double-tracer autoradiographic technique. Both images were identical in distribution throughout the whole flow areas. However, LCBF values were much lower in HMPAO than in IMP. The results suggest that HMPAO acts as a chemical microembolus in rat brain in both low and high flow areas; however, a quantitative flow measurement is difficult in an HMPAO study.

Amphetamines↗

Effect of the plasticizer di-(2-ethylhexyl)phthalate on oxidative phosphorylation in rat liver mitochondria: modification of the function of the adenine nucleotide translocator.

The effect of di-(2-ethylhexyl)phthalate (DEHP) on oxidative phosphorylation of isolated rat liver mitochondria was investigated. DEHP at concentrations of 20-1000 microM had no effect on state 4 respiration, but at 40 microM, DEHP decreased the rate of state 3 respiration by about 20%. Although DEHP had no effect on electron transport through the respiratory chain, it decreased the rate of adenosine triphosphate (ATP) synthesis. Its inhibition of ATP synthesis showed a similar concentration dependence to that of state 3 respiration. Furthermore, DEHP at 40 microM inhibited the uptake of [3H]adenosine diphosphate into mitochondria. DEHP also retarded the action of cationic uncoupling agents, which are known to modify the 29000-dalton protein involved in adenine nucleotide exchange. These results suggest that DEHP affects the activity of adenine nucleotide exchange and consequently partially decreases the rate of state 3 respiration. The action of DEHP on the 29000-dalton protein involves a protective effect against mitochondrial damage induced by hydrophobic cations or heavy metal cations.

Adenosine Diphosphate↗