ATP and ADP hydrolysis in cell membranes from rat myometrium

Extracellular nucleotides affect female reproductive functions, fertilization, and pregnancy. The aim of this study was to investigate biochemical characteristics of ATP and ADP hydrolysis and identify E-NTPDases in myometrial cell membranes from Wistar albino rats. The apparent K _m values were 506.4?±?62.1 and 638.8?±?31.3?μM, with a calculated V _max (app) of 3,973.0?±?279.5 and 2,853.9?±?79.8?nmol/min/mg for ATP and ADP, respectively. The enzyme activity described here has common properties characteristic for NTPDases: divalent cation dependence; alkaline pH optimum for both substrates, insensitivity to some of classical ATPase inhibitors (ouabain, oligomycine, theophylline, levamisole) and significant inhibition by suramine and high concentration of sodium azides (5?mM). According to similar apparent K_m values for both substrates, the ATP/ADP hydrolysis ratio, and Chevillard competition plot, NTPDase1 is dominant ATP/ADP hydrolyzing enzyme in myometrial cell membranes. RT-PCR analysis revealed expression of three members of ectonucleoside triphosphate diphosphohydrolase family (NTPDase 1, 2, and 8) in rat uterus. These findings may further elucidate the role of NTPDases and ATP in reproductive physiology.     

The quest for Y-chromosomal markers - methodological strategies for mammalian non-model organisms

Tracing maternal and paternal lineages independently to explore breeding systems and dispersal strategies in natural populations has been high on the wish-list of evolutionary biologists. As males are the heterogametic sex in mammals, such sex-specific patterns can be indirectly observed when Y chromosome polymorphism is combined with mitochondrial sequence information. Over the past decade, Y-chromosomal markers applied to human populations have revealed remarkable differences in the demographic history and behaviour between the sexes. However, with a few exceptions, genetic data tracing the paternal line are lacking in most other mammalian species. This deficit can be attributed to the difficulty of developing Y-specific genetic markers in non-model organisms and the general low levels of polymorphisms observed on the Y chromosome. Here, we present an overview of the currently employed strategies for developing paternal markers in mammals. Moreover, we review the practical feasibility and requirements of various methodological strategies and highlight their future prospects when combined with new molecular techniques such as next generation sequencing.     

Über das gelbe Pigment der Ganglienzellen,seine kolloid-chemischen und topographischen Beziehungen zu andern Zellstrukturen und eine elektive Methode zu seiner Darstellung

Zusammenfassung Das gelbe Pigment der Ganglienzellen besteht aus einer (wahrscheinlich eiweißartigen) Grundsubstanz, einer in gewissen organischen Lösungsmitteln löslichen, mit Fettfarbstoffen färbbaren Substanz und einem gelben Farbstoff, welcher der Grundsubstanz anhaftet.Die Grundsubstanz färbt sich mit basischen Farbstoffen primär. Diese Färbung ist im Gegensatz zur primären Färbung derNissl-Schollen nicht alkoholbeständig und muß daher fixiert werden.Die Grundsubstanz des Pigments und ihre Färbbarkeit sind alkalibeständig, während die primäre Färbbarkeit derNissl-Schollen in alkalischen Bädern verschwindet. Daher kann man nach Aufhebung der Färbbarkeit derNissl-Schollen eine elektive Färbung des Pigments mit basischen Farbstoffen und an ein und derselben Zelle nacheinander dasNissl-Bild und das Pigmentbild erhalten.Der p_H-Bereich, in welchem sich elektiv dieNissl-Schollen und elektiv die Pigmentgranula färben, ist deutlich verschieden. Am weitesten im Sauren liegt der isoelektrische Punkt derNissl-Substanz, dann kommt derjenige der Pigmentgrundsubstanz, und schon nahe dem Neutralpunkt liegt derjenige der Ganglienzellgrundsubstanz und der Fibrillen.Topographisch stimmt die Lage der großen Pigmentflecke mit den ausgesparten gelblichen Stellen desNissl-Bildes überein. Kleinere Pigmentstellen können aber vomNissl-Bild überdeckt sein.     

The in vitro physiological phenotype of tomato resistance to Fusarium oxysporum f. sp. lycopersici

Summary With the aim of dissecting host-parasite interaction processes in the system Lycopersicon aesculentum-Fusarium oxysporum f. sp. lycopersici we have isolated plant cell mutants having single-step alterations in their defense response. A previous analysis of the physiological phenotypes of mutant cell clones suggested that recognition is the crucial event for active defence, and that polysaccharide content, fungal growth inhibition, peroxidase induction in in vitro dual culture and ion leakage induced by cultural filtrates of the pathogen can be markers of resistance. In this paper we present the results of a similar analysis carried out on cell cultures from one susceptible (Red River), one tolerant (UC 105) and three resistant (Davis UC 82, Heinz, UC 90) tomato cultivars. Our data confirm that the differences in the parameters considered are correlated with resistance versus susceptibility in vivo. Therefore, these parameters can be used for early screening in selection programmes. These data, together with those obtained on isolated cell mutants, suggest that the selection in vitro for altered fungal recognition and/or polysaccharide or callose content may lead to in vivo — resistant genotypes. The data are thoroughly discussed with particular attention paid to the importance of polysaccharides in active defense initiation.     

Clinical importance of the lens opacities classification system III (LOCS III) in phacoemulsification

The aim of this study was to compare the correlation of features of cataracts graded by the Lens Opacities Classification System, version III (LOCS III) with recorded operative characteristics during the phacoemulsification. The retrospective study included 245 cases operated on by a single surgeon from October 2003 to March 2004. The cataract was graded at the biomicroscope using the 4 grading scales of the lens opacities classification system, version III (LOCS III); nuclear opalescence (NO), nuclear color (CO), cortical cataract (C) and posterior subcapsular cataract (P). We recorded 2 intraoperative characteristics: machine measured phacoemulsification time, and average machine power. The machine recorded phacoemulsification time and average power correlated positively with the estimated nuclear color (NC) scale and nuclear opaclescence (NO) scale. Grading within categories of cortical cataract (C) and posterior subcapsular cataract (P) did not correlate with any of the operative variables. Exponentially, greater phacoemulsification energy was required as NC and NO increased. LOCS III grading system enables the surgeon to anticipate potential pitfalls and to adapt the operative technique to the individual patient.