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Biomedical subjects

M Iwai

Publications and source records attributed to M Iwai.

At least 217 records · Page 12Linked to original sources
PubMed1987

Possible involvement of eicosanoids in the actions of sympathetic hepatic nerves on carbohydrate metabolism and hemodynamics in perfused rat liver.

In isolated rat liver perfused at constant pressure with Krebs-Henseleit buffer containing 5 mM glucose, 2 mM lactate, 0.2 mM pyruvate and 0.1% bovine serum albumin, perivascular nerve stimulation (20 V, 20 Hz, 2 ms) and infusion of ATP (100 microM), noradrenaline (1 microM) or arachidonic acid (100 microM) caused an increase in glucose and lactate output and a reduction of perfusion flow. The metabolic effects of nerve stimulation but not those of ATP and noradrenaline were inhibited strongly by the phospholipase A2 inhibitor bromophenacyl bromide (BPB, 20 microM) and the cyclooxygenase inhibitor indomethacin (Indo, 20 microM) and only slightly by the lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA, 20 microM). In contrast, the hemodynamic effects not only of nerve stimulation but also of ATP and noradrenaline were inhibited strongly by BPB and Indo and slightly by NDGA. The metabolic and hemodynamic actions of arachidonate were inhibited specifically by Indo. These results suggest that the effects of nerve stimulation were at least partially mediated or modulated by eicosanoids, especially by prostanoids.

Acetophenones↗
PubMed1987

Effect of ventromedial hypothalamic stimulation on blood flow of brown adipose tissue in rats.

The changes in regional blood flows to the rat's interscapular brown adipose tissue and several other tissues during electrical stimulation of the ventromedial hypothalamus (VMH) were studied using radioactively labelled microspheres. Measurement of blood flow was carried out, along with monitoring heart rate, under anesthesia and at thermoneutrality. During VMH stimulation the heart rate was clearly augmented and cardiac output increased about 45%. Regional blood flows were significantly increased in response to VMH stimulation in interscapular brown adipose tissue, adrenal glands, diaphragm and gastrocnemius muscles. The response of interscapular brown adipose tissue was the most prominent (approx. fifty-fold increase). Blood flows tended to decrease in spleen, lungs and kidneys during VMH stimulation, but did not change in liver or in other visceral organs. These observations suggest that the VMH is concerned with the regulation of regional blood flow to brown adipose tissue and contributes to thermogenesis in this tissue.

Adipose Tissue, Brown↗
PubMed1987

Biological significance of AFP-positive cells in rat livers with hyperplastic nodules induced by 3'-Me-DAB; combined immunocytochemical and radioautographical studies.

We investigated alpha-fetoprotein (AFP)-positive cells in 3'-Me-DAB hepatocarcinogenesis. In the early stage of 3'-Me-DAB hepatocarcinogenesis immunoreaction of AFP was detected in proliferating cholangiolar "oval" cells and in the late stage, AFP-positive cells, differing from oval cells, were detected in clusters in rat liver with hyperplastic nodules. The clusters of AFP-positive cells were morphologically classified into two different types of foci and one type of nodule. The combined techniques of immunocytochemistry and ratioautography revealed that AFP-positive foci and nodule had more 3H-thymidine labeling index than did areas without AFP-positive cells in liver with hyperplastic nodules; also one type of AFP-positive foci had a higher labeling index than the other type and in AFP-positive nodules there was active cell proliferation; but AFP-positive foci or nodules had less 3H-thymidine labeling than AFP-positive hepatoma cells. These findings suggested that AFP-positive foci and nodule had different biological significance in development of hepatocellular carcinoma and that AFP-positive foci with higher labeling index and AFP-positive nodule should be surveyed as preneoplastic population.

Animals↗
PubMed1987

Increased cholesterol concentration in intermediate density lipoprotein fraction of normolipidemic non-insulin-dependent diabetics.

There is increasing agreement about the atherogenicity of intermediate density lipoprotein (IDL). In order to determine whether normocholesterolemic diabetics are at a higher risk of atherosclerosis, cholesterol concentrations in three subclasses of triglyceride-rich lipoprotein fraction (Sf 12-400) were examined. Their plasma triglyceride and cholesterol levels were limited to below 150 and 250 mg/dl, respectively. They were divided into 3 groups according to their treatment: insulin injection (group I), sulphonylurea (group S) and diet alone (group D). Age-matched healthy normolipidemic non-obese subjects served as controls (group C). Triglyceride-rich lipoproteins were separated by ultracentrifugation: very low density lipoprotein (VLDL), Sf 60-400; intermediate density lipoprotein (IDL1), Sf 20-60; IDL2; Sf 12-20. Cholesterol concentrations in total plasma, VLDL, IDL2 and high density lipoprotein (HDL) were all identical in every group. A significant increase in cholesterol concentration was found in IDL1 of groups S and D. Low density lipoprotein-cholesterol of group I was also increased. These findings indicate an increased risk factor in normolipidemic diabetics.

Adult↗
PubMed1987

[Treatment of hepatocellular carcinoma with tumor thrombus in the main portal branch--analysis of five cases showing regression of the tumor thrombus].

Twenty-five cases of hepatocellular carcinoma with tumor thrombus in the first branch or trunk of the portal vein were treated with one-shot chemotherapy or transcatheter arterial embolization (TAE). Five of them showed regression of the tumor thrombus and survived 14 months on average. In these five cases, residual liver function was maintained at a good level. It was revealed that TAE was effective not only for tumors but also for tumor thrombi. But in cases with such tumor thrombus, normal liver tissue would be damaged by TAE. Therefore, residual liver function seems to be the most significant factor in choosing therapy.

Adult↗
PubMed1986

Effect of CS-514, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, on lipoprotein and apolipoprotein in plasma of hypercholesterolemic diabetics.

CS-514, one of the derivatives of ML-236B which is an inhibitor of endogenous cholesterol synthesis, has been previously shown to effectively reduce low density lipoprotein (LDL) cholesterol in dogs, rabbits and humans. We determined the effect of CS-514 on glucose, lipid, lipoprotein and apolipoprotein (apo) levels in plasma of 8 hypercholesterolemic diabetics (2 males). Total and LDL cholesterol and apo B levels were significantly decreased (P less than 0.005) 3 months after CS-514 treatment. High density lipoprotein (HDL) cholesterol was increased (P less than 0.05). Fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) did not change throughout the observation period. No clinically serious adverse effects were experienced by the patients. We conclude that CS-514 can be a useful drug in the treatment of hypercholesterolemic diabetics and is remarkably free of any evidence of toxicity or unwanted side effects even in diabetics.

Apolipoproteins↗
PubMed1986

Studies on pharmacological activation of human serum immunoglobulin G by chemical modification and active subfragments. IV. Induction of anti-inflammatory activity by chemical cleavage of interchain disulfide bonds in human immunoglobulin G and pharmacological activity of alkylated subfragments.

Commercially available human serum immunoglobulin G (IgG, native IgG) was separated into two fractions (Fr.I and II) using a diethylaminoethyl cellulose column. Heavy and light chains containing fractions were obtained from these two fractions after carboxamide-methylation. Thus, these fractions were subjected to an anti-inflammatory screening procedure and were shown to have a potent inhibitory activity against rat carrageenin induced paw edema, while no effect was observed in native IgG, Fr.I or II. The reduction and alkylation of the interchain disulfide bonds were essential to induce the anti-inflammatory activity. The anti-inflammatory activity of alkylated heavy and light chains of Fr.I (Fr.I-H and I-L) was also noted in subacute inflammation caused by the felt pellet and croton oil granuloma methods. Moreover, strong membrane stabilizing activities of Fr.I-H and I-L were demonstrated in vitro using rat red blood cell membrane and liver lysosomal membrane.

Alkylation↗
PubMed1986

[Acute myelogenous leukemia with only a 5q-chromosome abnormality].

A 68-year-old man with acute myelogenous leukemia (M2) was induced to complete remission by chemotherapy consisting of BH-AC and ACM-A on the 180th hospital day. Prior to therapy, chromosome analysis revealed 46, XY, del(5)(q22q33). No additional chromosome abnormalities were noted. Though 5q- was first associated with a preleukemic state, it is now known to be found in several different hematological disease. It has been suggested that patients with only a 5q- abnormality might have a better prognosis than those with a 5q- plus additional chromosome abnormalities. 5q- usually results from an interstitial deletion with break and fusion points at 5q11 or 12, 5q14 or 15, 5q22 and 5q33 or 35. The c-fms oncogene is located in the vicinity of band 5q34, so that a chromosome break at 5q33 or 34 may play an important role in the hematological disorders with 5q- chromosome abnormality.

Aged↗