Hyperthyroidism or increased thyroid function has been reported in many patients with trophoblastic tumors. In these cases, greatly increased human chorionic gonadotropin (hCG) levels and suppressed TSH levels suggest that hCG has thyrotropic activity. Recent investigations have clarified the structural homology not only in the hCG and TSH molecules but also in their receptors, and this homology suggests the basis for the reactivity of hCG with the TSH receptor. The clinical significance of the thyrotropic action of hCG is now also recognized in normal pregnancy and hyperemesis gravidarum. Highly purified hLH binds to recombinant hTSH receptor and is about 10 times as potent as purified hCG in increasing cAMP. The beta-subunits of hCG and hLH share 85% sequence identity in their first 114 amino acids but differ in the carboxy-terminal peptide because hCG beta contains a 31-amino acid extension (beta-CTP). A recombinant mutant hCG that lacks beta-CTP showed almost identical potency to LH on stimulation of recombinant hTSH receptor. If intact hCG were as potent as hLH in regard to its thyrotropic activity, most pregnant women would become thyrotoxic. One of the roles of the beta-CTP may be to prevent overt hyperthyroidism in the first trimester of pregnancy when a large amount of hCG is produced by the placenta. Nicked hCG preparations, obtained from patients with trophoblastic disease or by enzymatic digestion of intact hCG, showed approximately 1.5- to 2-fold stimulation of recombinant hTSH receptor compared with intact hCG. This suggests that the thyrotropic activity of hCG may be influenced by the metabolism of the hCG molecule itself. Deglycosylation and/or desialylation of hCG enhances its thyrotropic potency. Basic hCG isoforms with lower sialic acid content extracted from hydatidiform moles were more potent in activating adenylate cyclase, and showed high bioactivity/immunoactivity (B/I) ratio in CHO cells expressing human TSH receptors. This is consistent with the finding that the beta-CTP truncated hCG with higher thyrotropic potency is substantially deglycosylated and desialylated in the beta-subunit relative to intact hCG because all four O-linked glycosylation sites occur within the missing C-terminal extension. The desialylated hCG variant also interacts directly with recombinant hTSH receptors transfected into human thyroid cancer cells. There is thyroid-stimulating activity in sera of normal pregnant women, and this correlates with serum hCG levels. The thyroid gland of normal pregnant women may be stimulated by hCG to secrete slightly excessive quantities of T4 and induce a slight suppression of TSH, perhaps being about 1 mU/L less than nongravid levels, but not high enough to induce overt hyperthyroidism. Maternal thyroid glands may secrete more thyroid hormone during early pregnancy in response to the thyrotropic activity of hCG that overrides the normal operation of the hypothalamic-pituitary-thyroid feedback system. Biochemical hyperthyroidism associated with hyperemesis gravidarum has been att...

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Patients' age, low preoperative kana-hiroi test score, and low preoperative rSO2 were important risk factors for postoperative delirium.

Plant tannins, including hydrolysable and condensed varieties, are well known antioxidants in medicinal plants, foods, and edible fruits. Their diverse biological properties and potential for disease prevention have been demonstrated by various in vitro and in vivo assays. A number of ellagitannins, the largest group of hydrolysable tannins, have been isolated from dicotyledoneous angiosperms and characterized. This diverse class of tannins is sub-grouped into simple ellagitannins, C-glycosidic ellagitannins, complex tannins (condensates of C-glycosidic tannins with flavan-3-ol), and oligomers up to pentamers. This review outlines and describes the chemotaxonomic significance of structural features in various types of ellagitannins found in plants belonging to the Myrtaceae, Onagraceae, and Melastomataceae families, which are all included in the order Myrtales. Any biological activities that have been reported, including antitumor and antibacterial effects as well as enzyme inhibition, are also reviewed.

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To determine the possible involvement of brain amiloride-sensitive Na+channels in Na+-induced hypertension, we investigated the effects of benzamil hydrochloride, a specific blocker of these Na+channels, on the acute pressor mechanisms of intracerebroventricular infusion of hypertonic NaCl and the continuous pressor mechanisms of Na+-induced chronic hypertension, such as deoxycorticosterone acetate-salt hypertensive or stroke-prone spontaneous hypertensive rats, and of non-Na+-induced hypertension, such as renovascular hypertensive rats. Intracerebroventricular preinjection with benzamil (1 or 10 nmol/kg) abolished the increase in mean arterial pressure, heart rate, abdominal sympathetic discharge, and plasma vasopressin concentration induced by an acute increase in cerebrospinal Na+ concentrations at intracerebroventricular infusion of 1.5 M hypertonic NaCl. Continuous intracerebroventricular infusion of benzamil (1 or 10 nmol ⋅ kg−1 ⋅ day−1) for 7 days attenuated Na+-induced chronic hypertension in both deoxycorticosterone acetate-salt and stroke-prone spontaneous hypertensive rats, accompanied by reduction of urinary excretion of vasopressin and norepinephrine but not in renovascular hypertensive rats. Intravenous infusion of benzamil (10 nmol ⋅ kg−1 ⋅ day−1) for 7 days affected neither arterial pressure nor urinary excretion of vasopressin and norepinephrine in either model of hypertension. Benzamil-blockable brain amiloride-sensitive Na+ channels are expected to function as one of the Na+receptors in the brain and to be involved in the pressor mechanism of Na+-induced hypertension.

Four hydrolyzable tannins [oenothein B (1), eugeniflorin D(2) (2), and tellimagrandins I (3) and II (4)], two related polyphenolic compounds [gallic acid (5) and quinic acid 3,5-di-O-gallate (6)], and four myricetin glycosides [myricetins 3-O-beta-D-xyloside (7), 3-O-beta-D-galactoside (8), 3-O-beta-D-galactoside 6''-O-gallate (9), and 3-O-alpha-L-rhamnoside (10)] were isolated from the leaves of Myrtus communis. Antioxidant activities of the isolated compounds were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay.

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