A combined micro-and semi-micro colorimetric determination of long-chain fatty acids from plant cutin

Summary Re-examination of the colorimetric fatty acid determination with copper nitrate, followed by complex formation with DIECA has shown that the method is not reliable if applied as described by Duncombe (1962, 1963): The Cu concentration is too high, the DIECA concentration much too low and the wavelength chosen (440 m) is suitable only for very low fatty acid concentrations.According to the results reported here the following alterations have to be adopted: The concentration of the copper nitrate solution should be 3%, a 0.5% solution of DIECA in butanol has to be used and measurements should be done at 492 m. The method described here offers the opportunity to determine fatty acid concentrations in the semi-micro range by measuring the filtered chloroform phase directly at 691 m, covering a range between 175 g/ml to 1.2 mg/ml. If the concentration turns out to be lower than 200 g F. A./ml, the same sample can be used for a micro-determination (up to 200 g/ml) at 492 m, after formation of the yellowish-brown complex by addition of 0.1 ml 0.5% butanolic DIECA solution to 1.0 ml of the chloroform phase.The method has been applied to determine the amount of free F. A. in cutin layers and cutin powder, revealing that the latter contains 5.6 times more free F. A. than the intact material. The free F. A. within the polymer seem to serve as interconnections for the main units of the cutin polylipid.     

MORPHOLOGICAL AND BIOCHEMICAL CORRELATES OF CEREBRAL MICROSOMES : I. Isolation and Chemical Characterization

Microsomal fractions, both homogeneous in appearance and functionally operative, were isolated from a homogenate of rat cerebral cortex by fractionation in water. The preparations thus obtained contain the membranous elements of the endoplasmic reticulum, synaptic vesicles, and ribosomes. Esterase, ATPase, and glutamine synthetase were found to be present and fully functional in the microsomal fractions isolated in water. The contamination of the water-isolated microsomal fractions by mitochondria and lysosomes was found to be considerably lower than in microsomal pellets isolated in sucrose. The contamination by nerve ending particles, as judged by electron microscopy and by the levels of soluble lactic dehydrogenase entrapped in the cytoplasm of the particles, was also low. Most of the contamination by mitochondria and nerve ending particles could be removed by treatment of the microsomal pellet with 150 mM NaCl. Resistant to elution by this treatment is the lysosomal contamination as well as microsomal esterase and ATPase. Glutamine synthetase, on the other hand, was almost totally solubilized. Microsomal preparations isolated in water are also shown to contain amounts of protein, RNA, phospholipid, and ganglioside comparable to those found in microsomal preparations isolated in sucrose.     

Die Ausdrucksbewegungen der Sichelente,Anas falcata L.

Zusammenfassung Die Ausdrucksbewegungen der Sichelente,Anas (Eunetta) falcata Georgi, werden beschrieben, soweit möglich vorläufig analysiert und mit denen nächstverwandter Arten, vor allem denen vonAnas (Nettium) crecca crecca L.,Anas (Chaulelasmus) strepera L. undAnas (Mareca) penelope L. verglichen. Dieser Vergleich ergibt, genau wie der morphologischer Merkmale des Gefieders und der Knochentrommel, eine systematische Stellung vonfalcata genau zwischen den drei genannten Arten, näher den beiden erstgenannten als der dritten. Die Verteilung der Merkmal-Gemeinsamkeiten einerseits mitcrecca, andererseits mitstrepera, läßt den Schluß zu, daß die drei Arten divergent aus einer gemeinsamen Ahnenform entstanden seien. Keine gemeinsamen Merkmale, die bei anderen Arten fehlen, verbinden die drei genannten Formen zu einer Gruppe.Beim Gesellschaftsspiel der Sichelerpel sind, im Gegensatz zu dem aller anderen bisher daraufhin untersuchten Schwimmentenarten, alle beteiligten Bewegungsweisen, einschließlich des einleitenden Schüttelns, zur Ente hin orientiert, die hier, wie beicrecca undstrepera, am Spiel der Erpel sehr regen Anteil nimmt. Dagegen fehlen solche Bewegungen, die durch Ritualisierung aus Angriffsverhalten entstanden sind, beim Gesellschaftsspiel völlig, spielen aber eine große Rolle, analog dem Triumphgeschrei der Gänse und Tadorninen, beim Zusammenhalt der bereits verpaarten Tiere.     

DECREASE IN NUCLEAR FEULGEN-POSITIVE MATERIAL (DNA) UPON AGING IN IN VITRO STORAGE OF BOVINE SPERMATOZOA

The Feulgen-DNA content of sperm cells from 5 bulls was studied by means of microspectrophotometry after storage at 5°C for 2, 3, 5, and 10 days in a yolk-citrate diluent permitting slow aerobic metabolism. A subsample of sperm cells from each bull was subjected to the Feulgen technique on each of the storage days selected. The cells sampled on each of these days received a standard 12 minute, 60°C hydrolysis. Absorption measurements at 546 mµof the individual cells indicated a marked progressive decrease in the Feulgen-DNA content of the stored spermatozoa. The loss of 30 per cent of the initial DNA at the end of 5 days' storage was highly significant statistically. This decrease approximately parallels the known decrease in fertility of stored sperm cells, as well as the increase in apparent embryonic mortality resulting from the use of similarly aged spermatozoa for artificial insemination.     

THE ETIOLOGY OF SCHIZOPHRENIA—A Review

The causes and the nature of the psychiatric disorder labeled schizophrenia remain vexingly obscure. Perhaps as an expression of a still extant body-mind controversy, most of the experiments and statements made toward an elucidation of the problem follow one or the other of two opposing postulations: (a) That its origin is genetico-organic; (b) that it is environmental. In a review of the outstanding “facts” for either argument, it is notable that they presuppose not only a difference in theoretical frameworks, but two radically distinct outlooks. This is reflected in therapy, a field in which organicists and environmentalists stand even further apart; the organicist, relying heavily on electroshock and drugs, hopes to counteract a hypothetical body malfunction, and the environmentalist, through psychotherapy, attempts to make it possible for the patient to disentangle his own conflicting feelings and reaction patterns.Between the two an eclectic position seems hardly tenable. For, in spite of voluminous research and speculation, it has not been possible to build a bridge between the two camps and integrate different outlooks which, at times, have brought psychiatry almost to the point of schism.     

Electron Microscope Study of the Human Neuromuscular Junction

A preliminary electron microscope study of human neuromuscular junction is presented. The biopsy material was taken from the palmarus longus, and fixed routinely in osmium tetroxide and embedded in methacrylate. The structure of the motor endings and the relationship of the synaptic vesicles to the axolemmal membrane are described. The synaptic clefts are filled with an homogeneous material in continuity with the basement membrane covering the muscle fiber. The subneural apparatus is described, and special attention is paid to a vesicular component present in the sarcoplasm of the junctional area, which differs from synaptic vesicles and is presumed to be a derivate of the sarcoplasmic reticulum.     

Ueber den stand der Agrarmeteorologischen Forschung in der Deutschen Demokratischen Republik

Ohne Zusammenfassung     

The inconsistencies of present-day mathematical-physical methods pertaining to current generators in volume conductors used in electrocardiography

The present-day practices of electrocardiography and vectorardiography are based upon the theory that the surface potential differences can be assumed to be due to a single dipole inside the body. It is shown in this paper that a dipole cannot account for all the surface potentials due to realistic current generators, and hence the determination of the current generator from surface potential measurements based upon such a theory will lead to inconsistent representations of the heart for one and the same subject. To demonstrate this point two eccentric dipoles of different strengths and locations representing two muscle fibers are taken to be the current generator in a homogeneous spherical conductor. The exact surface potentials are then expressed by means of the “interior sphere theorem” of the authors. With these expressions the magnitude, direction, and location of the resultant dipole are determined by the method of D. Gabor and C. V. Nelson (J. App. Physics,25, 413–16, 1954). The surface potentials due to this resultant dipole are again exactly expressed by means of the “interior sphere theorem” and compared with those due to the eccentric dipoles assumed. It can be seen that the differences can be considerable. It is suggested that the multipole model of the authors (Bull. Math. Biophysics,20, 203–16, 1958) be used as a more accurate and the only unique representation of the heart. This investigation was supported by the National Heart Institute under a research grant H-2263(c).     

L'excursion en Provence (Sud-Est de la France) de la Societe Internationale de Phytosociologie

Conclusions La Provence apparaît, en définitive, comme un territoire des plus variés aux divers points de vue climatique, édaphique, biotique.C'est une région d'autant plus favorable aux études phytosociologiques que la variété des milieux s'y double d'une brutalité souvent étonnante des contrastes, conduisant à la juxtaposition parfois extrêmement précise d'associations végétales très différentes, dont les limites peuvent alors être cartographiquement figurées avec une très suffisante exactitude.Cette vigueur des contrastes est surtout marquée en Provence calcaire où les divers termes des séries évolutives dérivant du Quercetum ilicis climacique ou y conduisant, se juxtaposent souvent sans transition de quelque importance.Les contrastes sont cependant moins accusés en Provence cristalline et dans la Basse-Vallée du Rhône.En Crau comme en Camargue, les associations végétales se juxtaposent souvent en ceintures parallèles ou concentriques — elles s'individualisent alors facilement —, souvent en mosaïques irrégulières, au grè des variations locales des deux facteurs déterminants: l'eau en Crau, le sel en Camargue.En Provence cristalline, les Maures étant surtout faites de roches se délitant facilement (grès, micaschistes et phyllades) sous un climat chaud et humide, le sol se reconstitue facilement après sa destruction partielle par l'érosion; les contrastes sont moins tranchés; on observe des transitions nombreuses entre les divers termes des séries évolutives, dont les limites ne peuvent être fixées qu'approximativement. Nous y avons notamment abordé le problème de la forêt de chêne-liège dont la signification est loin d'être connue, non seulement en Provence mais sur toute l'étendue de son aire, en Afrique du Nord, en Espagne, au Portugal, en France méridionale, en Italie et dans les Iles de la Méditerranée occidentale.En provence cristalline, il est certain que l'homme en a considérablement assuré l'extension, directement pour l'utilisation du liège, indirectement par la coupe et le feu, et, en bien des points de la Méditerranée occidentale, le chêne-liège se présente comme une essence cultivée.Par ailleurs rien ne permet de mettre en doute son indigénat. Mais, dans les conditions actuelles du milieu en Provence cristalline:le chêne vert est possible partout;dans les conditions naturelles de la concurrence vitale le chêne vert l'emporte sur le chêne-liège.Si, donc, la forêt originelle a comporté le chêne-liège, ce ne peut être qu'à l'état d'essence secondaire et seulement en quelques points où une faible couverture forestière lui permettait de cohabiter avec le chêne vert.Les documents cartographiques au I/20 000^e tendent à montrer, d'aileurs que, dans les conditions naturelles de reconstitution de la forêt ou dans le peuplement naturel des sols neufs (Isthme de Giens), c'est la chênaie de chêne vert, non la chênaie de chêne-liège qui s'installe.Les grandes unités phytosociologiques de la Provence paraissent être maintenant convenablement définies floristiquement; il convient donc d'en poursuivre l'étude écologique, dont certains aspects seulement les plus apparents—mais peut-être pas toujours les plus actifs-, ont été abordés.Notons enfin la démonstration faite, au cours de l'excursion, de la parfaite application possible des méthodes phytosociologiques à l'étude des groupements marins et la nécessité, particulièrement apparente en milieu marin, de considérer tout autant les animaux que les végétaux. L'avenir est bien aux biocénoses dont les grands traits ont été mis en évidence, quant à la côte de la presqu'île de Giens, par Roger Molinier.Reçu par la rédaction le 20. XII. 1958.avec la collaboration de ROGER MOLINIER pour la partie marine et G. TALLON pour la Camargue.