37 research outputs found

    In Vitro and In Vivo Anti-Schistosomal Activity of the Alkylphospholipid Analog Edelfosine

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    BACKGROUND: Schistosomiasis is a parasitic disease caused by trematodes of the genus Schistosoma. Five species of Schistosoma are known to infect humans, out of which S. haematobium is the most prevalent, causing the chronic parasitic disease schistosomiasis that still represents a major problem of public health in many regions of the world and especially in tropical areas, leading to serious manifestations and mortality in developing countries. Since the 1970s, praziquantel (PZQ) is the drug of choice for the treatment of schistosomiasis, but concerns about relying on a single drug to treat millions of people, and the potential appearance of drug resistance, make identification of alternative schistosomiasis chemotherapies a high priority. Alkylphospholipid analogs (APLs), together with their prototypic molecule edelfosine (EDLF), are a family of synthetic antineoplastic compounds that show additional pharmacological actions, including antiparasitic activities against several protozoan parasites. METHODOLOGY/PRINCIPAL FINDINGS: We found APLs ranked edelfosine> perifosine> erucylphosphocholine> miltefosine for their in vitro schistosomicidal activity against adult S. mansoni worms. Edelfosine accumulated mainly in the worm tegument, and led to tegumental alterations, membrane permeabilization, motility impairment, blockade of male-female pairing as well as induction of apoptosis-like processes in cells in the close vicinity to the tegument. Edelfosine oral treatment also showed in vivo schistosomicidal activity and decreased significantly the egg burden in the liver, a key event in schistosomiasis. CONCLUSIONS/SIGNIFICANCE: Our data show that edelfosine is the most potent APL in killing S. mansoni adult worms in vitro. Edelfosine schistosomicidal activity seems to depend on its action on the tegumental structure, leading to tegumental damage, membrane permeabilization and apoptosis-like cell death. Oral administration of edelfosine diminished worm and egg burdens in S. mansoni-infected CD1 mice. Here we report that edelfosine showed promising antischistosomal properties in vitro and in vivo

    Chandra Spectral Measurements Of The O Supergiant ζ Puppis Indicate A Surprising Increase In The Wind Mass-Loss Rate Over 18 Yr

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    New long Chandra grating observations of the O supergiant ζ Pup show not only a brightening of the X-ray emission line flux of 13 per cent in the 18 yr since Chandra’s first observing cycle, but also clear evidence – at more than 4σ significance – of increased wind absorption signatures in its Doppler-broadened line profiles. We demonstrate this with non-parametric analysis of the profiles as well as Gaussian fitting and then use line-profile model fitting to derive a mass-loss rate of 2.47 ± 0.09 × 10−6[Math Processing Error]⁠, which is a 40 per cent increase over the value obtained from the cycle 1 data. The increase in the individual emission line fluxes is greater for short-wavelength lines than long-wavelength lines, as would be expected if a uniform increase in line emission is accompanied by an increase in the wavelength-dependent absorption by the cold wind in which the shock-heated plasma is embedded

    AUTOMATIC EXTRACTION OF DUNES FROM GOOGLE EARTH IMAGES NEW APPROACH TO STUDY THE DUNES MIGRATION IN THE LAÂYOUNE CITY OF MOROCCO

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    In desert environments, the sandy dune movements are considered as the main threat to the livelihoods and productivity of people living in Laâyoune city, South of Morocco. Studying dunes at a large scale requires intensive fieldwork and a huge dataset. But this task is not always easy because of the high cost and the limited availability of data. In this paper we present a new approach to study and evaluate the dune dynamic using Google earth archive image acquired from 2005, 2011, 2012, and 2013. To achieve this goal, an area with 3577 meter square including 40 barchan dunes, were selected, and the barchan dunes were automatically extracted from these images using Geographic Information System (GIS) and spatial analysis techniques provided by image processing software. The result shows not only the dune shape but also direction of dunes movements, and distance separating dunes. The obtained direction is ranging from North east to South west. The average rate of movement of the extracted dunes between 2005 and 2013 was calculated and is estimated at 32m per year. Validation of these dunes movement of the Laâyoune city was confirmed by the field data and previous studies

    A New Compact Rectangular Planar Antenna for THz Applications

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    Análise do líquido cérebro-espinhal de três doenças do sistema nervoso central de cães

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    RESUMO: Foi realizado um estudo retrospectivo do líquido cérebro-espinhal de cães (LCE), atendidos pelo Serviço de Neurologia do Hospital Veterinário da Instituição, de 2004 a 2015, com o objetivo de analisar os resultados de cães com sinais neurológicos, comparar as alterações encontradas em dois locais de colheita no mesmo paciente e verificar se esse exame auxiliou o clínico em reforçar a suspeita clínica das principais doenças do sistema nervoso central. A pleocitose linfocítica esteve presente em 78,3% (29/37) das amostras de cães com cinomose e em 23,2% (10/43) de cães com DDIV. Houve dissociação albuminocitológica (DAC) em 73% (19/26) das amostras de cães com tumores IC e em 64,3% (9/14) de cães com tumores envolvendo a ME. Em cães com DDIV, houve significância estatística (p<0,05) entre o grau de disfunção neurológica e o total de células nucleadas (TCN) e total de proteínas (TP). Em 29 cães, houve a colheita do LCE da cisterna magna e da cisterna lombar e em 12 (41,4%) os resultados foram diferentes entre as duas amostras colhidas do mesmo cão, onde dois (6,9%) apresentaram alteração na amostra colhida cranial à lesão. Pode-se concluir que a pleocitose linfocítica foi a principal alteração encontrada no LCE de cães com cinomose e DDIV e DAC nas neoplasias, IC e ME, cães acometidos pela DDIV apresentaram sinais neurológicos mais severos conforme o TCN e o TP aumentaram e o LCE sofreu alteração, mesmo colhido cranial ao local da lesão e auxiliou o clínico em reforçar a suspeita clínica, mas não confirmou, as principais doenças neurológicas em cães
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