Isolamento di Schizomiceti cellulositici,Attinomiceti, Eumiceti dall' intestino delle Termiti e ricerche sulla attivita' cellulositica degli Attinomiceti

Riassunto Gli AA. sono riusciti ad isolare, per la prima volta, Schizomiceti cellulositici del genere Cytophaga ed Attinomiceti del genere Actinomyces, dall'intestino delle Termiti. Sono altresí isolate alcune specie fungine, come era già noto. Gli Attinomiceti isolati non dimostrano di possedera capacità di attaccare la cellulosa, analogamente a quanto accade per altri ceppi di diversa provenienza degli stessi microrganismi.Gli AA. confrontano e discutono i loro resultati con quelli di altri AA. tendenti ad attribuire ai Protozoi simbionti delle Termiti una attività cellulositica, che ad essi non sembra sufficientemente provata. Gli AA. ritengono che tale attività si debba, invece, attribuire ai Batteri simbionti dei Protozoi e a quelli aderenti alle pareti dell'intestino delle Termiti stesse.

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Summary From the intestinal apparatus of the Termites were isolated, for the first time, cellulositic bacteria of the genus Cytophaga, in addition to ray-fungi of the genus Actinomyces and species of true fungi previously known. The cellulositic activity of Actinomyces has not been, instead, experimentally demostrated.The results obtained are discussed in relation to the presumed cellulositic activity of Protozoa symbiotic of the Termite ants.

     

Attività acetilcolinesterasica nel ganglio ciliare di cane

Summary The authors have studied the histochemical localization of acetylcholinesterase activity in the dog's ciliary ganglion by using the modified Koelle and Friedenwald technique. For better localisation of the structures stained by the histochemical method, some sections were in addition submitted to the Feulgen reaction, stained with Neutral red or impregnated according to the method of Bielschowsky.The results showed that if the pH of the incubating medium was 6,4, the pre- and postganglionic nerve branches as well as the nerve cell bodies react with a mean intensity only; the pericellular capsules, the sheathes formed by the satellite cells round the short processes and round the proximal part of the axone as well as the neurilemma of the nerve fibers between the ganglionic cells react as if they were the site of a very high enzymatic activity.At pH 5,2 of the incubating medium the authors observed the copper sulphide precipitate due to enzymatic activity to form a pattern resembling fibrillar woofs, sheathes, cords and rings of various dimensions; it now seems to be situated close to the ganglionic cell bodies and to the arches of its fenestrations and the precipitations appear to be in intimate contact with the deep side of the satellite cell sheath.The authors believe that the different results obtained in the first case may be explained by admitting that at pH 6,4 a massive staining of the satellite cells' capsules and sheathes may occur as the result of diffusion of the enzyme or of intermediate products from the preganglionic nerve fibers, which are the site of high acetylcholinesterase activity.     

Il ciclo del batterio simbionte di Blattella germanica (L.)

Résumé L'Auteur a étudié le cycle de la bactérie symbiote deBlattella germanica (L.) au cours de sa transmission éréditaire. Dans la fase de migration ovarienne, les bactéries font issue des bactériocytes de la femelle et franchissent, en un point encore mal connu, la paroi des tubes ovariens pour constituer une couche superficielle autour de l'oeuf.Au cours de la phase embryonnaire les bactéries convergent tout d'abord au centre du vitellus; puis lorsque à partir du mésoderme prennent naissance les lobes adipeux, les bactéries émigrent vers l'embryon, traversent l'entoderme et le sinus épineural et pénétrant dans le cytoplasme de diverses cellules mésodermiques transforment celles-ci en bactériocytes.

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L'argomento di questa ricerca mi è stato suggerito dal Prof. Raffaele Ciferri, ordinario di Botanica in questa Università, come parte a me assegnata di un complesso di ricerche, in collaborazione, sui simbionti del blattidi.     

Synthesis of thiazole and selenazole derivatives with affinity for the odorant-binding protein.

Three new ligands for odorant-binding proteins (OBPs) have been prepared, to be used in protein structure studies: the photoaffinity label 2-azido-4-butyl-5-propylthiazole, the NMR probe 2-trifluoromethyl-4-butyl-5-propylthiazole and the X-ray probe 2-amino-4-butyl-5-propylselenazole. All three compounds bind the bovine OBP with dissociation constants in the micromolar range.     

Trans-ethnic variation in germline variants of patients with renal cell carcinoma

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Cell cycle reactivation in cultured pea embryo axes. Effect of abscisic acid

Summary We used cultured pea embryo axes to study the effect of exogenous abscisic acid (ABA) on the reactivation of cell proliferation at germination. ABA (100 μM) was administered in a complete medium or in a medium without KNO₃ (the main source of K⁺ in the complete medium). In the presence of ABA, only a few meristematic root tip nuclei progressed through the cell cycle during the first 24 h of germination. Compared to the control the percentage of G₀/G₁ cells remained high. In the absence of KNO₃, the inhibitory effect of ABA on the cell cycle increased and the transition from G₁ to S was almost completely inhibited after 24 h of germination. Moreover, the amount of a 47 kDa nuclear protein remained high in embryos treated with ABA whereas it decreased in the control.     

Die Systematik der Actinomyceten

Summary Before the modern definition of the genereActinomyces, Micromonospora andProacgtinomyces, a historical-critical review of Actinomycetes (ray-fungi), based on personal, present and past, researches, has been made. A modern, analytical key for all Families, Subfamilies and Genera of Actinomycetales Buchanan, has been furnished. Of particular-importance is the discussion on the reproductive bodies and on the general morphology, fundamental for the taxonomy of Actinomycetes.A few selected, most important species are accurately described (with sinonimy) and discussed from the historic-experimental points of view, namely:Actinomyces Bostroemi, A. albus, A. sulpureus, A. carneus, A. Madurae, A. viridis, A. melanosporeus, A. innominatus andProactinomyces asteroides.

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Sumario El Autor, después de una sintesis histórico-critica sobre los Actinomicetos, en base a sus proprias buscas experimentales actuales y passadas, formula la moderne diagnosis de los génerosActinomyces, Micromonospora, Proactinomuces. etc., integrando, además, su estudio con una llave analitica moderna de todas las Familias, Subfamilias y Generos de los Actinomycetales Buchanan. De particular impprtancia es la discusión sobre la naturaleza de los cuerpos reproductivos de los Actinomicetos, y, màs generalmente, de la morfologia que está a la base de su sistematica.El Autor incluye la descripción cuidadosa de unas principales especies, reexaminadas desde el punto de vista historico-experimental, con sus ocmpleta sinonimia. Estas especies sonActinomyces Bostroemi, A. albus, A. sulphureus, A. carneus, A. Madurae,A. viridis, A. melanosporeus, A. innominatus, yProactinomyces asteroides.

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Riassunto L'autore, dopo una sintesi storico-critica sugli Actinomiceti, sulla base di proprie ricerche sperimentali recenti e passate, formula la diagnosi moderna dei generiActinomyces, Micromonospora, Proactinomyces, ecc. fornendo inoltre una moderna chiave sistematica per tutte le Famiglie, Sottofamiglie, e Generi degli Actinomycetales Buchanan. Di particolare importanza è la discussione sulla natura dei corpi riproduttivi degli Actinomiceti ed in genere sulla morfologia che sta a base della sistematica.Include la descrizione accurata di alcune delle principali specie, revisionate dal punto di vista storico-critico e sperimentale; queste specie sono provviste della completa sinonimia (Actinomyces Bostroemi, A. albus, A. sulpkureus, A. carneus, A. Madurae, A. viridis, A. melanosporeus, A. innominatus, Proactinomyces asieroides).

     

Cell cycle kinetic analysis with flow cytometry in pea root meristem synchronized with aphidicolin

Meristematic cells in pea root were synchronized after treatment with aphidicolin. Flow cytometric analysis of DNA content variations revealed a variety of information: ca 50% of the cells were synchronized in the first part of the S phase; kinetic studies of the S-phase traverse revealed an increase of the DNA synthesis rate from early to late S; some of the cells in the meristem were non-cycling, arrested in Gl (19%) and G2 (12%). The possibility of using such a synchronized system in cytogenetic and biomolecular studies is discussed.