Sympatric occurrence of Culex pipiens (Diptera,Culicidae) biotypes pipiens,molestus and their hybrids in Portugal,Western Europe: feeding patterns and habitat determinants

Culex (Culex) pipiens (Diptera: Culicidae) has two recognized biotypes, pipiens and molestus, which differ in physiology and behaviour; this difference may influence vectorial capacity for West Nile virus (WNV). Our goal was first to determine the presence of Cx. pipiens populations in 31 locations in Portugal and to subsequently analyse their host‐feeding preferences and habitat determinants. Molecular identification of Cx. pipiens forms and their hybrids was performed in 97 females; bloodmeal sources were identified in 59 engorged specimens. Overall, 61.9% of specimens were identified as Cx. pipiens f. pipiens, 20.6% as Cx. pipiens f. molestus, and 17.5% as hybrid forms. Culex pipiens f. pipiens fed preferentially on birds, and Cx. pipiens f. molestus on humans. Hybrid forms fed mostly on birds, but human bloodmeals were common. With reference to habitat, Cx. pipiens f. pipiens and hybrid forms were positively correlated with peri‐urban habitats. Our results confirm the sympatric presence of different Cx. pipiens biotypes in 14 of the 31 locations studied. Peri‐urban areas were a common habitat of all biotypes and may represent zones of hybridization. The feeding preferences and sympatric distribution of the Cx. pipiens biotypes observed in Portugal favour the epizootic circulation of WNV and the occurrence of disease outbreaks of WNV.     

Molecular polarity dependence of the transformed steroid effect on Na,K-ATPase

The transformed steroids containing an additional cycle E (delta-lactone or 16.23-pyranone) or 23-carbethoxy side chain (1.10(-5) M) inhibit Na,K-ATPase from pig kidney medulla. The steroid structure has a noticeable effect on ATPase inhibiton varying from 9 to 35%. The data obtained suggest that the position, stereochemistry and the uneven distribution of polar substituents in the steroid molecule are essential for ATPase inhibition by steroid aglycons.     

The effect of the distribution of polar groups in a steroid molecule on its inhibition of Na+,K+-ATPase

Transformed steroids having oxidized side chains in the D ring site and varying by polarity of the substituent at the ring A C(3)-position--acetates, glucosides or with free hydroxyls--in the concentration range 1 X 10(-4) - 1 X 10(-7) M were found to inhibit Na+, K+-ATPase. The extent of inhibition decreases with the rise in the polarity of the A region of the steroid molecule. With the compound devoid of polar groups in the D region an increase in the inhibitory activity is observed on passing from 3-acetate to 3-glucoside. The data obtained confirm the relationship between the extent of Na+, K+-ATPase inhibition and biphilicity of the molecule.     

Hypoderma actaeon: an emerging myiasis in roe deer (Capreolus capreolus)

Subcutaneous larvae of Hypoderma spp. (Diptera: Oestridae) were detected in the dorsal region in 10 roe deer, Capreolus capreolus (Artiodactyla: Cervidae), hunted in central Spain between January and March 2016. All larvae were found in the inner side of the hide during the skinning of the animals. The study of the morphological features of eight larvae of different stages collected from two animals allowed the identification of Hypoderma actaeon Brauer. The small size (4–5 mm) of some of the first instars suggests that the internal lifecycle of H. actaeon may be exclusively subcutaneous. This is the first confirmation of H. actaeon in roe deer; however, further studies to assess the spread of the parasite and to follow the evolution of this myiasis in roe deer are needed.     

The Lower Devonian conodont Pedavis pesavis and the pesavis Zone

Valenzuela-Ríos, 7.1. 1994 10 15 The Lower Devonian conodont Pedavis pesavis and the pesavis Zone.
Records from Europe and Western North America suggest that a diversification of Pedavis faunas took place around the base of what has been called the pesavis Zone. This level is reviewed in comparison to sequences in Western North America and Spain. Hitherto, two different taxa, Pedavis pesavis S.S. and Pedavis striatus (= Icriodus pesavis of Klapper 1969) have been used indiscriminately in defining the base of the pesavis Zone. This revision points out that the chronostratigraphic problems derived from an unknown phylogenetic history of both P. striatus and P. pesavis remain still unsolved, and thii fact challenges the continued use of either taxon as a zonal index for dating and correlating purposes. To improve this situation a new biostratigraphic unit above the delta Zone is proposed, the pandora beta - gilberti unit. This unit is unambiguosly defined, and thus it now enables accurate correlation on a global-scale basis above the delta Zone. Conodonts, biostratigraphy, Lower Devonian, Pyrenees, Nevada .     

New species of yeast from soil--Candida podzolica sp. n]

A new species of Candida podzolica is described. This species is widely distributed in podzolic and soddy-podzolic soils of the forest zone and in krasnozem. The yeast belongs to the nitrate-negative species of the genus Candida Berkhout, which do not ferment sugars, and is similar to the species C. humicola and C. curvata inhabiting soil. C. podzolica has a peculiar shape of the cells and does not produce films in liquid media. Extracellular polysaccharides contain glucose, mannose, galactose, and xylose; G+C in DNA is 62 mole percent.     

Structural basis of steroid compounds interaction with "digitalis"-receptor sites of Na,K-dependent ATPase

Twenty-two Steroid molecules have been tested for the inhibition Na,K-dependent ATPase at 10(-7)-10(-4) M concentrations. At the 10(-5) M concentration of the investigated molecules, inhibition ranged from 8 to 36%. To explain the structure-inhibition % relationship, we determined the value of heteropolarity or biphilicity moment of these molecules. This value would appear to be dependent on the space location and hydrophilicity of the molecule elementary fragments, and to the degree of their water accessibility; however, it is independent of the hydrophilicity of the molecules as a whole. On the basis of the obtained data, details of Na,K-ATPase digitalis-receptor structure and the mechanism of the glycoside-receptor interaction are discussed.