Fluorophotometric enzyme immunoassay of thyroid-stimulating hormone.

A method for enzyme immunoassay of thyroid-stimulating hormone (TSH) is described, TSH was conjugated with horseradish peroxidase according to periodate oxidation method. Separation of the bound and free was obtained by double-antibody solid-phase technique using Sepharose 4B-anti-rabbit immunogiobulin G (IgG)-geat IgG. The fluorescence reaction using tyramine and hydrogen peroxide as substrates was used for the determination of enzyme activity in order to increase the sensitivity of enzyme immunoassay. The standard curve for serum TSH was satisfactory to recognize TSH concentrations as 0.06 μU/tube. TSH values obtained by this method correlated well with those obtained by radioimmunoassay (r, 0.96). The coefficients of variation were 1.8 to 5.3% (within assay) and 5.1 to 10.5% (between assay). The method is about equal to radioimmunoassay with respect to sensitivity. Since it requires minimal equipment and is less expensive than radioimmunoassay, it is possible to perform routine assays even in laboratories with limited facilities.     

Phylogenetic study of the oxytocin-like immunoreactive system in invertebrates

1. A phylogenetic study of oxytocin (OXT)-like immunoreactive cells was performed by the PAP method in the central nervous system of invertebrates. 2. The immunoreactivity was detected in the nerve cells of Hydra magnipapillata of the Coelenterata; Neanthes japonica and Pheretima communissima of the Annelida; Oncidium verrucosum, Limax marginatus and Meretrix lamarckii of the Mollusca; and Baratha brassica of the Arthropoda. 3. No immunoreactive cells were found in Bipalium sp. of the Platyhelminthes; Pomacea canaliculata, Aplysia kurodai, Bradybaena similaris and Achatina fulica of the Mollusca; and Gnorimosphaeroma rayi, Procambarus clarkii, Hemigrapsus sanguineus, Helice tridens and Gryllus bimaculatus of the Arthropoda; Asterina pectinifera of the Echinodermata; and Halocynthia roretzi of the Protochordata. 4. These results demonstrate that an OXT-immunoreactive substance is widely present not only in vertebrates but also in invertebrates. 5. OXT seems to have been introduced into these invertebrates at an early stage of their phylogenetic history.     

Effects of some protein kinases, cyclic nucleotides and specific inhibitors of phosphorylation on the mitotic cycle of Physarum polycephalum

The true slime mould Physarum polycephalum was treated with various agents by spraying them upon the cell surface 4 hrs before the second synchronous mitosis. The onset of mitosis was considerably approximated after the plasmodium treatment with protein kinases from rat hepatoma or Ph. polycephalum at the late G2 phase. The catalytic and regulatory subunits of cAMP-dependent pig brain protein kinase caused retardation of mitosis, while the holoenzyme, casein kinase and alkaline phosphatase did not affect the timing of mitosis. The cyclic nucleotides and inhibitors of their metabolic enzymes were used to investigate the role of phosphorylation processes in the mitotic cycle.     

In vitro assessment of the selectivities of various beta-adrenergic blocking agents

Intrinsic sympathomimetic- and membrane activities of beta-adrenoceptor blocking agents are of little or no clinical significance. A selective blockade of cardiac receptors has important therapeutic consequences, especially in the treatment of patients with obstructive airways diseases. Profound depression of miocardial contractility can be deleterious in patients with cardiac muscle damage and the use of beta-adrenergic blockers with a quantitative selectivity towards chronotropism may become an important consideration. The effects of a number of beta-sympatholytics have been determined on isolated cardiac preparations (beta₁-adrenergic receptors) and tracheal preparations (beta₂-adrenergic receptors) of guinea-pigs. Results indicate that prindolol is the most selective blocker of the beta₁ chronotropic receptors whilst atenolol could be classified as being the most cardioselective beta-adrenergic blocker investigated. Butoxamine, on the other hand, proved to be the most beta₂-selective one.     

An extensive hairy root production precedes shoot regeneration in protoplast-derived calli of cauliflower (Brassica oleracea var. botrytis)

Summary Protoplasts isolated from mesophyll tissues of cauliflower (Brassica oleraceavar. botrytis) were induced to divide in culture, with 2% of them producing calli. Upon transfer to a regeneration medium containing a low auxin/cytokinin balance (0.02mg/l 1-naphthaleneacetic and 2mg/l 6-benzylaminopurine), they displayed an extensive production of hairy roots before the regeneration of shoots. Negative effects of root differentiation on the subsequent caulogenesis by such calli were not observed, since 97% of the calli regenerated hairy roots and 93% gave shoots.Abbreviations NAA 1-naphthaleneacetic acid - BAP 6-benzylaminopurine - 2,4 D 2,4-dichlorophenoxyacetic acid - GA3 gibberellic acid - MES 2-N-morpholinoethane sulfonate