Ultrastructural study of patch-graft re-endothelialization

Summary On the 8th post-operative day, an endothelial layer covers the venous patch luminal part when the adventitia of the patch is sutured to a 5–8 mm-long arteriotomy performed in the common carotid of the rat. The probable origin of this secondary endothelium is discussed.Supported by a grant from Banco Urquijo, Madrid, Spain.     

Pharmacologic study of several alpha-adrenolytics

Six alpha-adrenoceptor blocking agents have been investigated in dogs and rats. 170 150 and 170 153 have been found the most potent of these agents. At low doses (0,1 microgram/kg) they reversed the pressor response to low doses of adrenaline (0,1 and 0,3 microgram/kg) and suppressed the response to high doses of adrenaline. They reduced the pressor response to noradrenaline. In addition, in dogs 170 150 increased the tachycardia caused by stimulation of the cardiac nerve. The compound prevented and reversed the inhibition caused by clonidine on the effects of cardiac nerve stimulation. 170 153 did not increase the tachycardia caused by cardiac nerve stimulation, but it prevented and reversed the inhibitory effects of clonidine on this stimulation. The results show that 170 150 and 170 153 are potent alpha-adrenoceptor blocking agents acting on both pre and post-synaptic alpha-adrenoceptors which could be interesting pharmacological tools.     

Morphological study of paramyxovirus Yucaipa]

Paramyxovirus Yucaipa exhibits a dramatic polymorphism. One can observe round particles, 250 nm in diameter, and numerous filamentous forms, some of which are 1800 nm long.     

Immuno-electronmicroscopic study of human EA rosettes

Summary The immuno-electronmicroscopic study of human EA rosettes, using ferritin-labelled anti-human IgG antiserum, showed clusters of ferritin granules at the points of contact between erythrocytes and lymphoid cells, indicating that the links between Fc fragment of IgG on the surface of erythrocytes and specific receptor on the surface of lymphoid cell correspond to the sites of morphological interaction between the 2 cell types.recipient of a Grant of the Italian Consiglio Nazionale Ricerche.     

Fourier transformation study of corneal stroma

The various patterns observed by generating Fourier transforms of the fixed normal corneal stroma are described. The patterns are analysed in terms of the dimensions of the stromal fibers, the dimensional and directional order of the fiber distribution and the order of the fiber-fiber functions by proteoglycans.     

A study of transamination system inFusarium

Zusammenfassung AusFusarium lycopersici wurde ein Enzympräparat gewonnen, welches Glutaminsäure durch Transaminierung aus -Ketoglutarsäure bildete. Von den geprüften 20 Aminosäuren dienten die folgenden als Donatoren der Aminogruppe: Tyrosin, Ornithin, Alanin, Methionin, Leucin, Isoleucin, Prolin, Phenylalanin, Tryptophan, Valin und Asparaginsäure. Das Transaminasesystem scheint nicht an Strukturen des Cytoplasmas gebunden zu sein. Die Resultate stimmen im Prinzip mit jenen überein, welche beiNeurospora und bei Hefen gefunden wurden.     

Comparative study of sleep cycles in rodents

Zusammenfassung Bei Nagetieren (Kaninchen, Ratte, Maus) vergleichbarer Gehirnorganisation sind die Schlafcyclen, die durch regelmässiges Alternieren von (a) generalisierter langsamer unregelmässiger hochvoltiger Aktivität und (b) neokortikaler Desynchronisierung und regelmässiger hippocampaler -Aktivität charakterisiert sind, um so schneller, je kleiner die Tiere sind. Dies zeigt, dass der Mechanismus des Alternierens der Schlafphasen von Stoffwechselfaktoren, die im unteren Teil des Hirnstammes liegen, kontrolliert ist.     

A microradiographic study of ovarian dermoid teeth

Zusammenfassung Die Struktur von Zähnen aus ovarialen Dermoidzysten wurde mikroradiographisch mit Röntgenstrahlen untersucht, deren Wellenlängen dem eng begrenzten Absorptionsmaximum von Calcium entsprachen. Dabei zeigten sich im Dentin viele interglobuläre Räume, eine Erweiterung der hypokalzifizierten juxtapulpalen Zone und eine unregelmässige Oberfläche der Pulpa, die auf grossen, vaskulären Ausbuchtungen beruhte. Es wird angenommen, dass diese Erscheinungen auf einer durch die vaskuläre Abnormalität der Pulpa bedingten Störung der Mineralisation beruhen.     

A morphological study of delayed muscle soreness

Summary Biopsies, taken up to 1 week postexercise, from the soleus muscles of 5 healthy males (20–34 years old) suffering from pronounced exercise-induced delayed muscle soreness were analyzed morphologically. There was no evidence for ischemic tissue injury or mechanical fibre disruption. However, at the subcellular level frequent myofibrillar disturbances, especially with regard to the Z-bands, were noted. Thus, the contractile machinery of overloaded muscle fibres seemed to be partially distorted several days following exercise.     

Ultrastructural study of vanadocytes in Ascidia malaca

Summary The ultrastructural aspects of vanadocytes, found in the circulating blood of Ascidia malaca, were studied in formaline-fixed material. The results indicate that the diverse morphological aspects of vanadophores reported here, are probably concerned with different metabolic stages of vanadine.This work was supported by a grant from the University of Naples at the Zoological Station of Naples.     

A histochemical study of denervated marsupial hemidiaphragm

Summary The marsupial (quokka) hemidiaphragm showed postdenervation hypertrophy and subsequent atrophy. The type II muscle fibres hypertrophied up to 20 days postoperation and then regressed. However, the type I fibres hypertrophied throughout the experimental period (100 days) studied. Unlike denervated eutherian hemidiaphragm, fibre-splitting was absent in the denervated marsupial muscle. An enhancement of the ATPase reaction in the denervated type I fibres may be due to dedifferentiation. Presumably innervation exerts a negative control and prevents increase of type I fibre size in the normal hemidiaphragm.I am grateful to Dr O.M. Sola and Professor B.A. Kakulas for their help and encouragement.