Effects of Ca2+ and Mg2+ on motility of sea urchin spermatozoa

Summary Swimming speed of sea urchin spermatozoa, measured by a light scattering technique, did not change with 0-20 mM Ca²⁺ in the medium. The speed was maximum at the normal concentration of Mg²⁺ (49 mM) in sea water.Supported by grants-in-aid from the Ministry of Education, Science and Culture, Japan, and a grant from the Ford Foundation.     

Cytotoxicity of new cytochalasans fromChaetomium globosum

Zusammenfassung Nachweis, dass CHCl₃-Rohextrakte aus Myzelien und Filtraten der Zuchtmedien vonChaetomium globosum Kunze ex Fries einen akuten toxischen Effect auf HeLa-Zellen in vitro, sowie auf Mäuse zeigten. Chaetoglobosine die aus Mycelium-Rohextrakt isoliert wurden und chemisch zu den Cytochalasanen gehören, induzierten in HeLa-Zellen eine Polynukleierung und multipolare Kernverteilung. Auch beim Chaetogobosin wird eine Mikrofilament-Schädigung angenommen.     

Histochemical and ultrastructural modifications of mice endometrium, vagina and pituitary following zeranol treatment

The histochemical and ultrastructural changes produced by zeranol treatment on the endometrium and the gonadotropic FSH cells of the adenohypophysis have been investigated in mice at the prepuberal and virginal stages. Modifications similar to those induced by estrogen treatment were observed. It is concluded that both estrogens and zeranol share the same activity on the tissues examined.     

Structure of an antibody combining site by magnetic resonance.

The structure of the combining site of the DNP binding IgA mouse myeloma protein MOPC 315 has been determined by a combination of high resolution nuclear magnetic resonance, electron spin resonance, model building and chemical modifications. This approach yields that general dimensions of the site, its polarity and asymmetry features, the assignment of the DNP-contact residues and their three-dimensional coordinates.     

Immunochemical identification of vitellogenin in the serum of the newtTriturus cristatus

Summary The hematic yolk precursor — vitellogenin — has been identified immunochemically in the serum of estrogenized females of the newtTriturus cristatus by employing an antiserum prepared against yolk proteins.