1,721,047 research outputs found
On the distribution in Italy of the neartic hopper Acanalonia conica (Say) Hemiptera: Acanaloniidae), with ecological notes
No full textZephyr’s wings: Tiepolo’s imagination or the antlion Pseudimares Kimmins, 1933 (Neuroptera, Myrmeleontidae) as his model?
No full textWhen Giambattista Tiepolo, in his painting ‘Triumph of Zephyr and Flora’, gave Zephyr dragonfly- like wings with eyespots, was he inspired by pure imagination or did he have an insect he had previously seen in mind: the rare and astonishing Pseudimares? It is impossible to be sure. The authors of the present note point out the innovatory characteristic of the pictorial arrangement adopted by Tiepolo for the wings, compared with stylistic elements which were fashionable before and during his epoch, and suggest the reasons why we cannot rule out that the artist could have been inspired by a model, a specimen of Pseudimares, two centuries before the scientific discovery of this very rare antlion, at present only known from Iran and Morocco. A short account is provided on the bio-ecological significance of the eyespots found on insect wings
State of the art on Neuropterida of Sicily and Malta
No full textSicily, the largest Mediterranean island, is surrounded by many small islands (Aeolian Islands, Ustica, Aegadian Islands, Pantelleria, Linosa, Lampedusa, Maltese Islands), some of which forming archipelagoes. The authors, after a historical sketch of the research on Neuropterida in Sicily (sensu lato), analyze the biodiversity of the area, highlighting the species richness and providing an up-to-date check-list. The lack of knowledge on some of the most paradigmatic communities of Neuropterida is discussed in relation to their various habitats. The distributional patterns of Sicilian Neuropterida are interpreted in order to obtain a biogeographical characterization of the area. It is confirmed that the location of Sicily and its surrounding islands forms a bridge between north and south and a door from the W Mediterranean region to the oriental Mediterranean basin
Myrmeleon mariaemathildae n. sp.: a new Mediterranean pit-building antlion (Neuropterida Myrmeleontidae)
No full textBile acid structure and intestinal absorption in the animal model
No full textA close structure-activity relationship exists between the transport of bile acids (BA) in the liver and intestine; hepatic and intestinal BA transport can be evaluated and compared by using perfused liver and perfused intestine in the rabbit. The passive intestinal absorption is limited to the unconjugated BA, which occurs throughout the small bowel and colon, and is conditioned by the apical membrane lipid composition. A higher diffusion component is found in the terminal ileum compared to the jejunum, and seems to be related to the higher cholesterol-to-phospholipid ratio of the ileal brush border membranes. The active transport system is well characterized and the brush border membrane receptor, cytosolic BA binding proteins and basolateral anion exchange protein have been identified. Recently, the ileal BA transporter has been cloned from the hamster and human ileum and the main cytosolic BA binding protein was cloned from the rat ileum. In the liver, the active transport predominates on the passive diffusion both for conjugated and unconjugated BA. The maximal transport capacity in the liver is tenfold higher than in the intestine, while the Km values are of the same order of magnitude, i.e. in the millimolar range. Neither system operates at its maximum transport rate with prevalent concentrations of BA in portal blood or luminal content
The Neuropterida of Triveneto (Northern Italy): an updated faunal checklist with some zoogeographical remarks
No full textNew insights in the physiology and molecular basis of the intestinal bile acid absorption
No full textIntestinal bile acid absorption is a fundamental step in the enterohepatic circulation and metabolism of these endogenous compounds. The physiology of the active, sodium coupled transport system for bile acids in the terminal ileum has been extensively studied and characterized. Structure-activity studies have elucidated the requirements for the ileal transport system, and studies with photolabile bile acid derivatives identified the putative ileal bile acid transport proteins. Characterization of the functional sites of the transport system elucidated some of the possible mechanisms which allow the interaction of bile acids and sodium ions with the ileal transporter. Considerable progress has been made during recent years, after the ileal apical and cytosolic bile acid transport proteins have been cloned and characterized. The role of point mutations in bile acid malabsorption has been studied, and the knowledge of the amino acid sequence of the transport proteins will be of help in the investigation of the transport mechanisms
Larvae of Gymnocnemia variegata (Schneider, 1845) and Megistopus flavicornis (Rossi, 1790) (Neuroptera Myrmeleontidae)
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