A genetic study of intergradation betweenMytilus edulis andMytilus galloprovincialis

Summary A study of geographic variation at 2 diagnostic allozyme loci in the musselsMytilus edulis andM. galloprovincialis reveals considerable spatial variation, both in allele frequencies and in the extent of intergradation.This work was supported in part by grant GR3/2452 from the NERC. We thank M. Hunt, A. Dunn and M. Newton for technical assistance and the many people who gave advice or helped in the collection of specimens.     

A genetic study of intergradation between Mytilus edulis and Mytilus galloprovincialis

A study of geographic variation at 2 diagnostic allozyme loci in the mussels Mytilus edultis and M. galloprovincialis reveals considerable spatial variation, both in allele frequencies and in the extent of intergradation.     

Paramyosin-Struktur und Sperrtonus,Untersuchungen am Byssusretraktor vonMytilus edulis mit dem Interferenz-Kontrast-Mikroskop

Summary Surviving muscle fibres of a molluscan smooth muscle (ABRM) in catch exhibit a characteristic pattern of longitudinal stripes when examined with theNomarski technique (Differential interference contrast). The pattern appears to be due to aggregated paramyosin-filaments; it disappears after abolishing the catch with 5-hydroxytryptamine or — in freeze-dried preparation — after raising the pH of the ATP-salt solution.     

Untersuchungen an Bariumtitanat-Einkristallen

Summary It was possible to produce bariumtitanate monocrystals with ferroelectric qualities, which is shown in the temperature curve of the dielectric constant, in the resonance frequency, and also in hysteresis phenomena.     

The occurrence of filamentous banded elements as components ofMytilus galloprovincialis byssus

Résumé L'examen au microscope électronique de sections ultra-minces de différentes portions du byssus deMytilus galloprovincialis a révélé pour la première fois la présence de structures filamenteuses périodiques (FBE). Leur période a une longueur de 1000 Å en moyenne, elle est symétrique et comporte deux fractions: A et B. Il est possible que ces structures correspondent à une organisation particulière de la protéine collagène.     

Untersuchungen an saponinhaltigen Homogenaten

Summary These investigations are a contribution to the study of problems caused by homogenisation. It is shown that saponines in homogenates of leaves of Viola tricolor really react with the suspended chloroplasts.     

Demonstration of vitamin D3 metabolism inmytilus edulis

Summary Radiolabeled vitamin D₃ was converted into several polar metabolites upon incubation with tissue homogenates from the common musselMytilus edulis. Chromatographic analysis indicated that the metabolites have chromatographic mobilities different from those of known standards. The results suggest that vitamin D₃ is metabolized in mussels via pathways that differ from the vertebrate systems.Acknowledgments. The authors thank Dr Pirjo Rantamäki for the mussels and F. Hoffmann-La Roche & Co. for supplying the vitamin D₃ metabolite standards. This work was supported by a grant from the Magnus Ehrnrooth Foundation to T. K.     

The lectins fromAgaricus edulis. Isolation and characterization

Summary 2 lectins from the mushroomAgaricus edulis were isolated, after heating the crude extract at 75°C, by ion exchange chromatography and gel chromatography using QAE-Sephadex A-50 and Sephadex G₇₅. Some hemagglutinating and physicochemical properties of the agglutinins are reported.     

Zytologische Untersuchungen an der Reblaus-Blattgalle

Summary Up to 9 types of cell nuclei, distinguished by their size, were found in the tissue of galls, which are produced by the vine louse. The growth of the cell nuclei probably proceeds in a series of prophase-like intermediate stages from one type of nuclei size to the next largest by means of endomitotic or endomitosis-like processes.     

Elektronenmikroskopische Untersuchungen an den Herzklappen

Summary The heart values of the rabbit were examined by electronmicroscope. The endothelium consists of a single layer of flat cells. Adjacent cells may overlap over extensive areas. The endothelial cells contain numerous tonofilaments. This structure is functionally and dynamically interpreted. The subendothelial connective tissue is called spongiosa. The fibrosa consists of bundles of collagenous fibres.     

Untersuchungen zur biologischen Wirksamkeit eines A-homo-Testosteronacetates

Summary The biological efficiency of a high purified A-homo-testosterone-acetate was tested on male mice. We found no inhibition of the gonadotropic partial-function of the anterior pituitary by the substance; and furthermore no substitution of testosterone deficit after castration was possible.     

Vergleichende Untersuchungen an Proteinen von Influenzaviren

Summary Evidence is mainly indirect that certain animal RNA viruses integrate host material into their envelope. For example, influenza adapted to Ehrlich ascites tumor is immunogenic against the tumor cells in mice. However, even in polyacrylamide, it was impossible to find significant differences in protein composition of influenza WSA grown in different hosts, whereas differences between strains could easily be detected. The conclusion is that host protein integration is improbable.

---

---

Arbeit mit Unterstützung des Schweizerischen Nationalfonds zur Förderung der wissenschaftlichen Forschung (Kredit Nr. 5254.3). Frl.U. Kohler danke ich für Mitarbeit und Herstellung der Skizzen.     

Untersuchungen zur Neurosekretion beiAcheta domesticus L

Summary PAF-positive material, which is found in the brain and stomatogastric system of adultAcheta domesticus, can in addition be demonstrated in the Nervus corporis allati II. In the suboesophageal ganglion and the ventral nerve cord 3 different types of neurosecretory cells are described.     

Interferenzmikroskopische Untersuchungen an Medulloblastom- und Glioblastomzellen

Summary The dry mass per unit area (g/µ²) for nucleus and cytoplasma was determinated by interference microscope from 1043 glioblastoma cells of 5 various glioblastomas and from 439 medulloblastoma cells of 4 various medulloblastomas. The values obtained from the glioblastoma cells are significantly higher than the values of medulloblastoma cells.

---

---

Mit dankenswerter Unterstützung der Deutschen Forschungs gemeinschaft.     

Experimentelle Untersuchungen zur Pathogenese des Kontaktekzems

Summary The mechanism of development of contact eczema, which might serve as a working hypothesis for other clinical forms of eczema, is not yet fully understood. An attempt was made, by means of sensitization with Dinitrochlorobenzol in guinea-pigs, to determine the time and place of the pathogenetic phenomena, as well as the organs and tissues affected. Experiments on skin-explants permitted the separate investigation of the different systems, i.e. the blood, nerve and lymphe, presumed to be involved.It was ascertained that the lymphatic system is absolutely essential for the development of sensitization, and the blood path for its generalized spread.

---

---

Ausführliche Publikation erscheint demnächst in Dermatologica, Basel.     

Enzymhistochemische Untersuchungen am Subfornikalorgan der Ratte

Summary In the rat, thirst leads to an increase of glucose-6-phosphate-dehydrogenase activity in the subfornical organ, and to a decrease in choroid plexus.     

Untersuchungen zur Thermodynamik des peripheren Sehprozesses

Summary In a range from 6 to 30°C, the influence of temperature on the relation between the light intensity and the amplitude of the b-wave of the exposure potential has been investigated for the isolated frog retina. Between 10 and 25°C, the gross activation energy of the response to light leads to a temperature coefficient which shows that the formation of the b-wave is mainly checked by diffusion processes. While at 6°C the b-wave has vanished, a complete delayed off-response can still be registered.     

ZNS-aktive Phenylpropylamine vonCatha edulis FORSK. (Celastraceae) kenyanischer Herkunft

Summary The phenylpropylamine fraction ofCatha edulis FORSK. grown in Kenya has been investigated. The major components have been found to be (S)-(–)--aminopropiophenone (1), (+)-norpseudoephedrine (2) and(–)-norephedrine (3). Quantitative ratios of1, 2, 3 in tissues of different age are discussed.

---

ZNS-aktive Phenylpropylamine vonCatha edulis FORSK. (Celastraceae) kenyanischer Herkunft