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rootworm contamination, of which the important advantages of the former modeling methods (visual calculation methods, sticky insect traps) are their low costs and their easy and quick application. These methods provide a relative estimate for population

Open access
Acta Chromatographica
Authors: A. Ochoa, J. Fechine, J.C. Escalona, J. García, S.G. dos Santos, and M. Sobral da Silva

Excoecaria lucida Sw. is an evergreen shrub widely distributed in Cuba and throughout the Caribbean region. In spite of its extended traditional use as antiasthmatic and antimicrobial by the local population, scientific reports on the species are almost nonexistent. This paper focuses on the isolation and characterization of compounds present in the crude extract of E. lucida Sw. leaves through the combined use of chromatographic and spectroscopic techniques (medium pressure liquid chromatography, thin-layer chromatography, gas chromatography, nuclear magnetic resonance 1H, and mass spectrometry). A total of 15 nonpolar substances were identified in the four main fractions obtained; some of these substances could be related with the antimicrobial properties attributed to the species.

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Prions of the baker’s yeast Saccharomyces cerevisiae allow for the inheritance of complex traits based solely on the acquisition of cytoplasmic protein aggregates and confer distinctive phenotypes to the cells which harbor them, creating heterogeneity within an otherwise clonal cell population. These phenotypes typically arise from a loss-of-function of the prion-forming protein that is unable to perform its normal cellular function( s) while sequestered in prion amyloid aggregates, but the specific biochemical consequences of prion infection are poorly understood. To begin to address this issue, we initiated a direct investigation into the potential control that yeast prions exert over fungal lipid content by utilizing the prions [URE3] and [PSI +], the first two prions discovered in yeast. We utilized silica gel high-performance thin-layer chromatography (HPTLC)—densitometry to conduct pair-wise quantifications of the relative levels of free sterols, free fatty acids, and triacylglycerols [petroleum ether—diethyl ether—acetic acid (80:20:1) mobile phase, phosphomolybdic acid (PMA) detection reagent]; steryl esters and squalene (hexane—petroleum ether—diethyl ether—acetic acid (50:20;5:1), PMA]; and phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol (chloroform– diethyl ether—acetic acid (65:25:4.5), cupric sulfate—phosphoric acid) in otherwise clonal prion-infected ([PSI +] or [URE3]) and prion-free ([psi ] or [ure-o]) cells in two growth phases: log-phase and stationary phase. Our analysis revealed multiple statistically significant differences (p < 0.00625) between prion-infected and prion-free cells. Interestingly, prion-induced changes varied dramatically by growth phase, indicating that prions exert differential influences on cell physiology between log and stationary growth. Further experimental replication and extension of the analysis to other prions is expected to resolve additional physiological effects of prion infection. This investigation demonstrates that HPTLC—densitometry is an effective method for studying prion-induced alterations in lipid content in yeast.

Open access

. , E vans , R. E. , L azorchak , J. M. & F lick , R. W. 2007 . Collapse of a fish population after exposure to a synthetic estrogen , Proceedings of the National Academy of Sciences of the United States of America . 104 . ( 21

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Northern Algeria is widely used by local population as food additive and in Algerian folk medicine for its antitussive, antiseptic, expectorant, anti-helmintic, and anti-spasmodic properties [ 3 ]. The herbal plant, like other production, can be

Open access
Acta Chromatographica
Authors: Samiuela Lee, Christa E. Nath, Ben W. R. Balzer, Craig R. Lewis, Toby N. Trahair, Antoinette C. Anazodo, and Peter J. Shaw

later confirmed in a population pharmacokinetic analysis [ 3 ] and in a recent exposure–response analysis that was conducted in 225 adults with ALK-positive non-small-cell lung cancer in which steady-state trough concentration was used as the clinically

Open access

SPSS (ver: 13) statistical package. Results and Discussion Technological developments and increasing population are accompanied by growing interest and demand to the innovations in the field of health. In this context

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of PCBs. However, sample size was insufficient, and further investigation is required to assess the exposure of the Japanese population to PCBs. Acknowledgment These studies were supported by grants for

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), occupy a large share of the pharmaceutical market due to the increase in the elderly population, many of whom have hypertension. BBs are competitive antagonists at β-adrenergic receptor sites and are used to treat cardiovascular disorders, such as

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Introduction Tobacco smoke contains numerous hazardous components and contributes to serious adverse outcomes [ 1 ]. In Jordan, tobacco smoking is widely popular among the general population. In 2015, the World Health

Open access