Gender differences in a Drosophila transcriptomic model of chronic pentylenetetrazole induced behavioral deficit

A male Drosophila model of locomotor deficit induced by chronic pentylenetetrazole (PTZ), a proconvulsant used to model epileptogenesis in rodents, has recently been described. Antiepileptic drugs (AEDs) ameliorate development of this behavioral abnormality. Time-series of microarray profiling of heads of male flies treated with PTZ has shown epileptogenesis-like transcriptomic perturbation in the fly model. Gender differences are known to exist in neurological and psychiatric conditions including epileptogenesis. We describe here the effects of chronic PTZ in Drosophila females, and compare the results with the male model. As in males, chronic PTZ was found found to cause a decreased climbing speed in females. In males, overrepresentation of Wnt, MAPK, TGF-beta, JAK-STAT, Cell communication, and Dorso-Ventral axis formation pathways in downregulated genes was previously described. Of these, female genes showed enrichment only for Dorso-Ventral axis formation. Most significant, ribosomal pathway was uniquely overrepresented in genes downregulated in females. Gender differences thus exist in the Drosophila model. Gender neutral, Dorso-Ventral axis formation may be considered as the candidate causal pathway in chronic pentylenetetrazole induced behavioral deficit. Prior evidence of developmental mechanisms in epileptogenesis underscores the usefulness of fly model. Gender specific pathways may provide a lead for understanding brain dimorphism in neuropsychiatric disorders

Generalized Newton's Method based on Graphical Derivatives

This paper concerns developing a numerical method of the Newton type to solve systems of nonlinear equations described by nonsmooth continuous functions. We propose and justify a new generalized Newton algorithm based on graphical derivatives, which have never been used to derive a Newton-type method for solving nonsmooth equations. Based on advanced techniques of variational analysis and generalized differentiation, we establish the well-posedness of the algorithm, its local superlinear convergence, and its global convergence of the Kantorovich type. Our convergence results hold with no semismoothness assumption, which is illustrated by examples. The algorithm and main results obtained in the paper are compared with well-recognized semismooth and $B$-differentiable versions of Newton's method for nonsmooth Lipschitzian equations

Glycosylated Oligo(ethynylene)s via a Pd/Zn-Mediated Cross-Coupling Reaction

The synthesis of higher oligo(ethynylene)s represents a challenge in modern organic chemistry, because of their decreasing stability with increasing length and side-product formation during the reaction. Recently, we reported the development of a mild and convenient sp–sp carbon heterocoupling protocol for the preparation of glycosylated oligo(ethynylene)s based on the Negishi reaction. The application of this protocol in combination with a one-step desilylation-bromination allowedfor the sequential synthesis of glycosylated oligo(ethynylene)s up to the octayne

Do we use the appropriate controls for the identification of informative methylation markers for early cancer detection?

It is possible to miss potential DNA methylation markers of tumorigenesis because profiling results are initially filtered on the basis of inappropriate controls