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Anillinus cornelli Sokolov and Carlton, new species
No full textAnillinus cornelli Sokolov and Carlton, new species (Fig. 23, Map fig. 42) Holotype (USNM). Male labeled / NC Gaston Co. Crowders Mt St Pk 23 VI82 JF Cornell pine log litter 982 VI23-3 / HOLOTYPE, Anillinus cornelli Sokolov and Carlton, des. 2004/. Paratypes (11). Three males and 1 female, same data as holotype; 1 male labeled / SC York Co nr Kings Mt Kings Mt St Pk 20 V 72 JF Cornell / (JFC); 1 male labeled / SC York Co Kings Mt St Pk nr Kings Mt 9 I 83 JF Cornell Ulogs stones stream Debr 983-I-9-2C/; 5 males labeled / SC York Co Kings Mt St Pk Oct 28, 89 JF Cornell 989- X-28-3/ (JFC). Specific Epithet. The species is named after Jim Cornell, collector of the type series and many other specimens of the genus. Description. Medium-sized for genus (ABL range, 1.61–2.08 mm, mean, 1.90 mm, n ¼ 10). Habitus moderately convex, ovoid (WE/ABL, 0.38); head normally proportioned for genus (WH/ WPm, 0.80); pronotum and elytra relatively narrow (WPm/WE, 0.75). Color of body brunneus, appendages testaceous. Microsculpture of head limited to small triangular area at middle of vertex and frontal impressions, absent from disc of pronotum. Pronotum moderately convex, and transverse (WPm/LP, 1.16), with margins rectilinear and slightly constricted posteriad (WPm/WPp, 1.10). Anterior angles evident, slightly prominent. Posterior angles slightly obtuse (1058). Width between posterior angles slightly greater than width between anterior angles (WPa/WPp, 0.91). Elytra moderately convex, moderately depressed along suture, of normal length for genus (LE/ ABL, 0.54), with traces of 2–3 interneurs. Humeri moderately prominent, slightly rounded. Vestiture of elytra relatively short (less than one-fourth the length of the discal setae). Males with metafemora simple. Median lobe (Fig. 23) arcuate, twisted, with small, narrowly rounded apex. Internal sac with copulatory pieces of dorsal and ventral sclerites. Dorsal sclerite strongly arched near midpoint of median lobe, apex extending far beyond internal sac when fully extended. Ventral sclerite formed from three elongate subapical tubercles. Distribution. This species is known from two nearby localities in Gaston County, North Carolina (Crowders Mountain State Park) and York County, South Carolina (Kings Mountain State Park) (Fig. 42). Habitat. The holotype was collected in pine log litter. Differential Diagnosis. Anillinus cornelli is ovoid in form without microsculpture on the forebody (Table 2, group VIII of litter species). It is distinguished from all other species in this group (for which males are known) by the form of the median lobe and armature of the internal sac. This species is apparently allopatric with respect to other described species of Anillinus and likely is sympatric with at least one species of Serranillus. From A. loweae it differs by the absence of microsculpture at the disc of pronotum and in lacking head microsculpture, except a small triangle at the middle of the vertex, and by the distinctive aedeagus. Anillinus cornelli is similar to A. murrayae in habitus and the general shape of the main dorsal copulatory sclerite of the aedeagus and may represent its allopatric sister taxon. In A. cornelli that structure is more strongly arched and elongate than it is in A. murrayae. Also, the accessory aedeagal sclerites of the two species are quite different, with A. cornelli lacking the ventral blade-like sclerite and clusters of spines. Anillinus cornelli also differs in having the male metafemora not expanded (i.e., evenly convex along posterior margin) and the tubercles along the posterior margin are much smaller and are visible only under very high magnification and strong illumination.Published as part of Sokolov, Igor M., Carlton, Christopher & Cornell, James F., 2004, Review of Anillinus, with Descriptions of 17 New Species and a Key to Soil and Litter Species (Coleoptera: Carabidae: Trechinae: Bembidiini), pp. 185-233 in The Coleopterists Bulletin 58 (2) on pages 209-210, DOI: 10.1649/61
Squalene: strong points and weaknesses[Squalene pregi e difetti]
No full textSqualene typically represents isoprene derived structures. In nature, squalene can be found in the plant kingdom, as well as in the animal kingdom, and even in archibacteria. In fact, squalene is an important structure which in the course of time has specialized, focusing on mostly structural and metabolic specific functions. In plant cell membranes, squalene probably modulates cation backscattering but its main characteristic is the fact that it cannot be employed as an energy source and that it can metabolically transform into cyclized structures such as hopanoids and steroids. In animal cells, squalene mostly acts as a substrate for the synthesis of cholesterol. Squalene is present in many kinds of food and it is likely to give a variable exogenous contribution. Therefore, its administration can increase the levels of all the intermediates and of the esterificated forms of sterols before cholesterol. Not only squalene does act as an intermediate of the cholesterol synthesis but it also stimulates the acyl-coenzyme A (cholesterol acyltransferase), which governs the esterification of cholesterol and which is also related to the levels of triglycerides. There is a sort of barrier between food squalene and cholesterol; such barrier makes their relationship finely articulated and involves the absorption and elimination of cholesterol itself. Therefore, a powerful administration or a supply of squalene do not produce an immediate cholesterol levels increase: there is no direct connection. Thus squalene's second major role is to regulate the processes of cholesterol absorption, synthesis, esterification and elimination. As far as lipoproteins are concerned, squalene's action can be considered similar to that of triglycerides. In fact, a close connection between squalene and triglycerides must be supposed, as far as the esterification processes related to the latter are concerned. The concentration of squalene in the deposits rich in triglycerides is such that it is unlikely to perform truly stoichiometric functions, such as the spacing between different lipidic chains, while squalene may act as a coenzyme. The fact that high levels of squalene can be observed in coronary heart diseases, particularly in menopausal women, must be evaluated with extreme care because that is probably a reactive growth which tends to increase the option of sterol esterification to counterbalance hyperlipoproteinemia. Therefore, the Mediterranean diet, provided it is not too rich in calories and it makes a balanced use of olive oil, rises in value since it seems to allow that kind of regulation. Squalene's antioxidant action is important too, especially on the skin, where its concentrations are extremely high thanks to its plentiful secretion through sebum. According to some in vitro tests on cellular cultures, squalene's antioxidant action is similar to that of the all-trans retinol. It is a summation of the quencher action of each isoprene unity. These last characteristics of squalene make it possible for us to use it as a human antioxidant, both for topic and systemic applications
Effect of a polyglucosamine on the body weight of male rats: Mechanisms of action
No full textPolyglucosamine (PG) is a low-molecular-weight chitosan (125. kDa) mixed with vitamin C and tartaric acid in standardised proportions. The aim of this study was to determine its effect on the body weight of male rats and clarify the mechanism of action. Three groups of 12 young male rats were fed a standard diet, or a diet containing PG (1% or 2%), for nine weeks. Body weight, food and water intake, and total cholesterol and triglyceride levels were measured before and at the end of treatment; low-density (LDL) and high-density lipoproteins (HDL), the amount of faeces, and their lipid, glucose and acetate content were also measured at the end of treatment.Total body weight increased by 234 ± 44.2. g in the controls, 233 ± 32.4. g in the rats fed PG 1%, and 206 ± 32.8 in those fed PG 2%; the weight increase was significantly less only in the PG 2% group, with the greatest difference being reached after four weeks (p< 0.01). Food intake was similar in all three groups. Twenty-four hour faecal weight/body weight was significantly higher (p< 0.05) in the animals treated with PG 2% than in the controls; faecal lipid, acetate, glucose and water content were also significantly higher in the PG 2% group. There was no significant change in the plasma lipid profiles of any of the groups.Dietary PG 2% reduces body weight, increases faecal weight (and faecal lipid and water content), and makes available fats and glucose as fuel for colon bacteria, as indicated by the higher acetate content
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