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Biomedical subjects

G Parisi

Publications and source records attributed to G Parisi.

At least 91 records · Page 5Linked to original sources

A simple model for the immune network.

In this note I present a simple model for the idiotypic network among antibodies and study its relevance for the maintenance of immunological memory; in particular, the memory capacity of such a model is studied. Some of the similarities with the spin glass model and with neural networks are discussed.

Animals↗

[Further characterization of the orange carotenoid protein extracted from the marine demosponge Axinella verrucosa].

The orange coloration of the marine sponge A. verrucosa is provided by some carotenoids widespread in the ectosome and mesohyl of this sponge. These carotenoids are bound to a glyco(lipo)protein forming a non covalent complex. Six carotenoids are bound to the glyco(lipo)protein, but only alpha-carotene was identified by HPLC. The aminoacid composition is quite different from those previously reported in Porifera. The content of Ser and Gly and the total polar residues are high. The presence of Met and Pro was not evidenced. Some unusual aminoacids were detected, of which only Taurine was probably identified.

Amino Acids↗

[Caroteno-protein complexes in Axinella verrucosa (Porifera: Demospongae)].

Carotenoproteins are common to a wide variety of animals, most notably invertebrates although other animal groups have been shown to have these complexes as well. In a previous paper alpha-carotene, renieratene, isorenieratene and an unknown isomer of renieratene were isolated, but at present nothing is known about nature of the carotenoid-protein complexes in A. verrucosa. In this paper we report our results about a carotenoid-protein complex extracted by TRITON X-100 and purified by Sephadex G 200 Fine and DEAE-Sephacel chromatography. This carotenoprotein had a molecular weight of ca. 390,000 dalton (Gel electrophoresis). SDS PAGE plate showed only a single polypeptide chain of ca. 50,000 dalton. The proteic band separated by PAGE plate electrophoresis showed the presence of lipids and glycids when stained respectively by Sudan Black B and by Schiff's reagent. The extract obtained without TRITON X-100 showed the presence of a similar carotenoid-protein complex, but because of the low proteic concentration this result should be confirmed.

Animals↗

Cystic meningiomas. Report of seven cases.

Seven patients with cystic meningioma are reported. The computerized tomography appearance of these meningiomas may mimic that of a glial or metastatic tumor with cystic or necrotic changes, and lead to an incorrect presumptive diagnosis. Radiological evaluation and recognition are important for the surgical removal of these potentially curable neoplasms.

Adolescent↗

Effects of L-carnitine on adriamycin-induced cardiomyopathy in rabbit.

The authors conducted an investigation in order to ascertain whether or not L-carnitine, by promoting the utilization of FFA for energy and neutralizing FFA toxicity occurring after ischaemia, could prevent or confine adriamycin-induced cardiotoxicity in rabbits. The results show that L-carnitine determines a higher survival rate and reduced onset of cardiomyopathy. Histopathological examination of myocardial tissue under light and electron microscopy revealed a marked decrease in mitochondrial lesions.

Animals↗

[Spectrophotometric study of several rhodamines commonly used in microscopy (1)].

Rhodamines, commonly used in microscopic studies, are basic dyes derived from xanthene. They have recently been used for the quantitative analysis of important cations, as well as in the vital staining of mitochondria of normal or pathological cells and also in the routine staining procedures. These applications may require a knowledge of the spectral behaviour of rhodamines. Here we report the visible and ultraviolet absorption spectra, together with the excitation and fluorescence spectra of the chromatographically pure samples of rhodamine B, rhodamine 6G and violamine R.

Microscopy↗

[Spectrophotometric study of several rhodamines commonly used in microscopy (2)].

From the examination of the visible and ultraviolet spectra, together with the excitation and fluorescence spectra of the chromatographically pure samples of rhodamine B, rhodamine 6G and violamine R, it is possible to establish the nature of the chromophores in the samples we have studied. In particular there is a report on the possible structures of resonance of rhodamine B, from which it is possible to understand the spectral behaviour of the rhodamines we have studied.

Microscopy↗