1,721,003 research outputs found
Dermotossicità di una preparazione di nematocisti di Carybdea marsupialis
No full textCarybdea marsupialis (Cnidaria, Cubozoa), a jellyfish found in the Adriatic Sea only in recent years, was previously considered innocuous and only recently has been described by us as dermotoxic to man. In the present study we evaluated the activity of a purified preparation of nematocysts of Carybdea marsupialis in men. A crude nematocystic fraction was tested by prick and patch test in 7 volunteers and by scratch-patch test in 20. In the prick test 0.1 ml of the suspension of nematocysts was applied on forearms, and then a slight prick was made with a needle at the centre of the drop. The reaction was read after 20 min. In the patch test 0.1 ml of nematocysts suspension were applied on forearms and covered by a suitable patch-tape. The reaction was read after 48 and 96 hrs. The scratch patch test consisted in producing a net (1 cm x 1 cm) of 3 vertical and 3 horizontal lines with a needle on the forearms without making it bleed. Then, 0.1 ml of the suspension were put on the scratched area and covered with a patch tape. The reaction was read after 48 and 96 hrs. All volunteers were also tested with distilled water. All the 7 subjects tested by prick and patch test resulted negative, while various degrees of erythema were observed only in 4 subjects tested by scratch-patch test. Our results confirm that Corybdea marsupialis is dermotoxic, even if only subjects with particularly sensitive skin suffer from its sting. This study shows that the procedure of purification we used is valid to maintain the dermotoxic activity of the preparation. The nematocysts separated from their cellular matrix appear unable to penetrate the intact skin, but maintain their capacity to release venom. In fact the purified preparation was inactive if tested in the prick and in the patch test. In contrast, its dermotoxic action was present when the skin barrier was altered as in the scratch-patch test. Therefore, scratch-patch test represents the most suitable method to evaluate the dermotoxicity of purified nematocysts
The effect of seawater temperature on the swimming activity of Pelagia noctiluca (Forsskål)
No full textAurelia polyps and medusae (Scyphozoa; Semaeostomeae; Ulmaridae) in the Northern Adriatic: their cnidome and ecology
No full textNematocysts play an important role in capturing prey; it was suggested that the feeding ecology of animals may result in cnidome variations. We examined nematocysts of polyps and medusae of Aurelia sp. 8 from the Northern Adriatic to detect differences/similarities in cnidome and habitats, and the results show that potential prey of these two phases of the life cycle are very different. Our observations on the nematocysts isolated from the marginal tentacles and oral arms of medusa have shown the presence of four types of nematocysts (in order of decreasing abundance): heterotrichous microbasic eurytele; atrichous isorhiza haploneme; heterotrichous isorhiza haploneme; heterothricous microbasic mastigophore (typeAI) and (A typeII). This last type is very rare (with a rel. freq. << 0.1%), and unexpected. In the polyps (tentacular crown and column) were found three types of nematocysts (in order of decreasing abundance): heterotrichous isorhiza haploneme; heterotrichous microbasic eurytele; atrichous isorhiza haploneme. The atrichous type is localized, being rare-absent in the tentacles, common in the peristomial area and in the column. Prey preferences of northern Adriatic Aurelia polyps and medusae are largely unknown. We attempted to elucidate their dietary habits using available information about stable carbon and nitrogen isotope ratios
Aspetti preliminari della morfologia degli otoliti di Leuciscus cephalus (Linnaeus, 1758) (Osteichthyes, Cyprinidae)
No full textCell-mediated sensitization to jellyfish antigens confirmed by positive patch test to Olindias sambaquiensis preparations
No full textBiology of pike, Esox lucius (Esocidae), in the lower plain of Friuli-Venezia Giulia (north-eastern Italy)
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Ciclo riproduttivo annuale femminile di Platichthys flesus italicus (Gunther, 1862) nella laguna di Marano
No full textAtti del 63° Congresso Nazionale UZI (Unione Zoologica Italiana), Rende (CS) 22-26 settembre 200
Anomalie nel ciclo riproduttivo del luccio, Esox lucius, nella pianura friulana (Torviscosa, Udine)
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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