Differential flight muscle development in workers, queens and males of the eusocial bees, Apis mellifera and Scaptotrigona postica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Annexin 1: differential expression in tumor and mast cells in human larynx cancer

Annexin 1 protein (ANXA1) expression was evaluated in tumor and mast cells in human larynx cancer and control epithelium. The effect of the exogenous ANXA1 (peptide Ac 2-26) was also examined during the cellular growth of the Hep-2 human larynx epidermoid carcinoma cell line. This peptide inhibited the proliferation of the Hep-2 cells within 144 hr. In surgical tissue specimens from 20 patients with larynx cancer, ultrastructural immunocytochemistry analysis showed in vivo down-regulation of ANXA1 expression in the tumor and increased in mast cells and Hep-2 cells treated with peptide Ac2-26. Combined in vivo and in vitro analysis demonstrated that ANXA1 plays a regulatory role in laryngeal cancer cell growth. We believe that a better understanding of the regulatory mechanisms of ANXA1 in tumor and mast cells may lead to future biological targets for the therapeutic intervention of human larynx cancer. (c) 2007 Wiley-Liss, Inc.

Differential distribution of some extracellular matrix fibers in an experimentally denervated rat megaileum

Absence of enteric neurons is associated with thickening of the intestinal muscularis externa in Chagas' disease. The thickening is due to hyperplasia and hypertrophy of the smooth muscle cells and increased extracellular matrix components. The influence of the nervous system on the structure of the smooth muscle cells and its associated matrix has been poorly investigated. An experimental model of denervation of the ileum in rats was performed by application of the surfactant agent benzalkonium chloride that selectively destroys the myenteric plexus. Three months later, ileal tissue samples were obtained and studied by histochemistry and transmission electron microsocopy. Sham operated rats were used as controls. The diameter of collagen fibrils was evaluated in electron micrographs. The histopathological analysis showed thickening of the muscular layer. The thin and weakly arranged collagen and reticulin fibers surrounding the smooth muscle cells, observed in control cases by Picrosirius polarization (PSP) stain method, corresponded to a population of loosely packed thin collagen fibrils of uniform diameters (mean = 29.16 nm) at the ultrastructural level. In contrast, the thick and strongly birefringent fibers around the muscle cells, observed in the treated group, stained by PSP, corresponded to densely packed thicker fibrils with large variation in diameter (mean = 39.41 nm). Comparison of the data demonstrated statistically significant difference between the groups suggesting that the replacement of loosely arranged reticulin fibers by fibrous tissue (with typical collagen fiber), may alter the biomechanical function resulting in impairment of muscular contraction. (c) 2007 Elsevier Ltd. All rights reserved.

Periodic solutions of abstract neutral functional differential equations

We characterize the existence of periodic solutions of some abstract neutral functional differential equations with finite and infinite delay when the underlying space is a UMD space. (C) 2011 Elsevier B.V. All rights reserved.

Searching for molecular markers in head and neck squamous cell carcinomas (HNSCC) by statistical and bioinformatic analysis of larynx-derived SAGE libraries

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Lie symmetry analysis and reductions of a two-dimensional integrable generalization of the Camassa-Holm equation

In this Letter we investigate Lie symmetries of a (2 + 1)-dimensional integrable generalization of the Camassa-Holm (CH) equation. Through the similarity reductions we obtain four different (1 + 1)-dimensional systems of partial differential equations in which one of them turns out to be a (1 + 1)-dimensional CH equation. We establish their integrability by providing the Lax pair for all of them. Further, we present a brief analysis for some types of particular solutions which include the cuspon, peakon and soliton solutions for the two-dimensional generalization of the CH equation. (C) 2000 Published by Elsevier B.V. B.V.

Symmetry analysis of an integrable reaction-diffusion equation

In this paper, we investigate the invariance and integrability properties of an integrable two-component reaction-diffusion equation. We perform Painleve analysis for both the reaction-diffusion equation modelled by a coupled nonlinear partial differential equations and its general similarity reduced ordinary differential equation and confirm its integrability. Further, we perform Lie symmetry analysis for this model. Interestingly our investigations reveals a rich variety of particular solutions, which have not been reported in the literature, for this model. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Stability results for impulsive functional differential equations with infinite delay

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Crystallization study of molybdate phosphate glasses by thermal analysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A thermal analysis study of dithizone and dithizonates of mercury, silver and bismuth

Foram preparados os ditizonatos de Hg (I), Ag (I) e Bi (III). Termogravimetria (TG), termogravimetria derivada (DTG), calorimetria exploratória diferencial (DSC), difratometria de raios X pelo método do pó e análise elementar foram usados para caracterizar e para estudar a estabilidade térmica e a decomposição térmica da ditizona e destes ditizonatos.

Comparative analysis of differentially expressed sequence tags of sweet orange and mandarin infected with Xylella fastidiosa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Application of voltammetric technique to the analysis of indanthrene dye in alkaline solution

The Indanthrene Olive Green B (C.I. Vat Green 3; C.I. 69500), VG3 dye, a vat dye bearing an anthraquinonoid group and a ketonic group, can be detected by differential pulse voltammetry in alkaline solution using glassy carbon electrode. on the adsorbed form the dyes are reduced into three cathodic steps at -0.54 V, -0.65 V and -0.93 V vs Ag/AgCl. The leuco form generated after previous electrolysis at controlled potential of -1 V can be detected by voltammetry due to its reoxidation peak at -0.08 V. An analytical method is proposed for determining the vat dye using modified glassy carbon electrode by electrochemical activation in alkaline medium. Linear relationship was observed between l(Pu) vs concentration from I X 10(-5) mol L-1 to 6.0 X 10(-4) mol L-1. The detection limit was calculated to be 9.3 X 10(-6) mol L-1. (c) 2005 Elsevier Ltd. All rights reserved.

SYNAPTONEMAL COMPLEX-ANALYSIS OF THE SEX BIVALENT IN GOATS

Synaptonemal complex (SC) analysis of XY pairing in the goat (Capra hircus; 2n = 60) was investigated by electron microscopy for the first time in this species. Synapsis of the X and Y chromosomes begins during the mid-late zygotene stage as the autosomes complete their pairing. Only a small portion of the total length of the Y is paired with the X chromosome at this time. By the early pachytene, almost 90% of the Y is paired with the X. All the observed stages of the sex bivalent pairing showed the structural difference between the differential and pairing regions. In the pairing region, a synaptonemal complex is formed, while in the differential region the chromosome axes remain free.

Differential pulse polarographic determination of clotrimazole after derivatization with Procion Red HE-3B

Clotrimazole was shown to react at room temperature in Britton Robinson buffer pH 2 with the reactive dye Procion Red HE-3B. The product exhibited a differential pulse polarographic peak at -0.38 V, which was well separated from the peaks of the reactive dye at -0.08, -0.80 and -0.95 V, and this allowed the indirect determination of clotrimazole in the presence of excess of the reactive dye. The method has been applied satisfactorily to the determination of clotrimazole in pharmaceutical formulations, calibration graphs are rectilinear up to at least 40 mug ml(-1). The detection limit was calculated to be 2.6 mug ml(-1) (3 sigma). (C) 2002 Elsevier B.V. B.V. All rights reserved.

Electrochemical study of hydroxychloroquine and its determination in plaquenil by differential pulse voltammetry

Hydroxychloroquine (HCQ) is a halogenated aminoquinoline that presents wide biological activity, often being used as an antimalarial drug. The electrochemical reduction of HCQ was investigated by cyclic voltammetry and chronoamperometry using glassy carbon electrodes. By cyclic voltammetry, in acid medium, only the cathodic peak was observed. The electrochemical behavior of this peak is dependent on pH and the electrodic process occurs through an ErCi mechanism. The electron number (le) consumed in the reduction of HCQ was obtained by chronoamperometry. A method for the electrochemical determination of HCQ in pharmaceutical tablets was developed using differential pulse voltammetry. The detection limit reached was 11.2 mug ml(-1) of HCQ with a relative standard deviation of 0.46%. A spectrophotometric study of HCQ has been also carried out utilizing a band at 343 nm. The obtained detection limit and the relative standard deviation were 0.1 mug ml(-1) and 0.36%, respectively. The electrochemical methods are sufficiently accurate and precise to be applied for HCQ determination, in laboratorial routine, which can be used to determine the drug at low level. (C) 2003 Elsevier B.V. B.V. All rights reserved.