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61.
Vera Lucia Lanchote Maria Paula C Marques Osvaldo Massaiti Takayanagui Roberto de Carvalho Fernanda Orsi Paias Pierina Sueli Bonato 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,709(2):528
A high-performance liquid chromatographic method has been developed for the simultaneous determination of albendazole sulfoxide (ABZSO) enantiomers and albendazole sulfone (ABZSO2) in human plasma. The resolution of ABZSO enantiomers and ABZSO2 was obtained on a Chiralpak® AD column using hexane–isopropanol–ethanol (81:14.25:4.75, v/v/v) as the mobile phase. The drugs were detected by fluorescence (λexc=280 nm, λem=320 nm). The drugs were extracted from 500 μl plasma with ethyl acetate, and after solvent evaporation, the residues were dissolved in the mobile phase and chromatographed. The method was precise and accurate for the three compounds, as judged by the coefficients of variation and relative errors observed. Linear standard curves were obtained in the concentration range of 5–2500 ng/ml for ABZSO enantiomers and 1–500 ng/ml for ABZSO2. A typical plasma concentration–time profile is presented for one patient under treatment for neurocysticercosis. 相似文献
62.
Jaime Gutiérrez Cristian A. Droppelmann Osvaldo Contreras Chiaki Takahashi Enrique Brandan 《PloS one》2015,10(8)
Fibroblasts are critical for wound contraction; a pivotal step in wound healing. They produce and modify the extracellular matrix (ECM) required for the proper tissue remodeling. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) is a key regulator of ECM homeostasis and turnover. However, its role in wound contraction is presently unknown. Here we describe that Transforming growth factor type β1 (TGF-β1), one of the main pro-fibrotic wound-healing promoting factors, decreases RECK expression in fibroblasts through the Smad and JNK dependent pathways. This TGF-β1 dependent downregulation of RECK occurs with the concomitant increase of β1-integrin, which is required for fibroblasts adhesion and wound contraction through the activation of focal adhesion kinase (FAK). Loss and gain RECK expression experiments performed in different types of fibroblasts indicate that RECK downregulation mediates TGF-β1 dependent β1-integrin expression. Also, reduced levels of RECK potentiate TGF-β1 effects over fibroblasts FAK-dependent contraction, without affecting its cognate signaling. The above results were confirmed on fibroblasts derived from the Reck
+/- mice compared to wild type-derived fibroblasts. We observed that Reck
+/- mice heal dermal wounds more efficiently than wild type mice. Our results reveal a critical role for RECK in skin wound contraction as a key mediator in the axis: TGF-β1—RECK- β1-integrin. 相似文献
63.
Claudio Stalder Agostina Vertino Antonietta Rosso Andres Rüggeberg Claudius Pirkenseer Jorge E. Spangenberg Silvia Spezzaferri Osvaldo Camozzi Sacha Rappo Irka Hajdas 《PloS one》2015,10(10)
Cold-water coral (CWC) ecosystems occur worldwide and play a major role in the ocean''s carbonate budget and atmospheric CO2 balance since the Danian (~65 m.y. ago). However their temporal and spatial evolution against climatic and oceanographic variability is still unclear. For the first time, we combine the main macrofaunal components of a sediment core from a CWC mound of the Melilla Mounds Field in the Eastern Alboran Sea with the associated microfauna and we highlight the importance of foraminifera and ostracods as indicators of CWC mound evolution in the paleorecord. Abundances of macrofauna along the core reveal alternating periods dominated by distinct CWC taxa (mostly Lophelia pertusa, Madrepora oculata) that correspond to major shifts in foraminiferal and ostracod assemblages. The period dominated by M. oculata coincides with a period characterized by increased export of refractory organic matter to the seafloor and rather unstable oceanographic conditions at the benthic boundary layer with periodically decreased water energy and oxygenation, variable bottom water temperature/density and increased sediment flow. The microfaunal and geochemical data strongly suggest that M. oculata and in particular Dendrophylliidae show a higher tolerance to environmental changes than L. pertusa. Finally, we show evidence for sustained CWC growth during the Alleröd-Younger-Dryas in the Eastern Alboran Sea and that this period corresponds to stable benthic conditions with cold/dense and well oxygenated bottom waters, high fluxes of labile organic matter and relatively strong bottom currents 相似文献
64.
Araucaria trees as host plants of the longhorned beetle Huequenia livida (Coleoptera: Cerambycidae) in Argentina are reviewed. Araucaria araucana is its natural host plant in SW Argentina, but the larvae also developed in dead branches of A. angustifolia and A. bidwillii (new host plant records), when both plants were kept in the same rearing cage with the natural host plant. Pinus contorta var. murrayana, also mentioned from Argentina, may be a recently adopted secondary host. A winter and a summer generation of H. livida was documented for the first time. Huequenia livida exceeds the actual natural distribution of A. araucana following the distribution of cultivated A. araucana and Pinus trees. 相似文献
65.
Osvaldo Zagordi Rolf Klein Martin D?umer Niko Beerenwinkel 《Nucleic acids research》2010,38(21):7400-7409
Next-generation sequencing technologies can be used to analyse genetically heterogeneous samples at unprecedented detail. The high coverage achievable with these methods enables the detection of many low-frequency variants. However, sequencing errors complicate the analysis of mixed populations and result in inflated estimates of genetic diversity. We developed a probabilistic Bayesian approach to minimize the effect of errors on the detection of minority variants. We applied it to pyrosequencing data obtained from a 1.5-kb-fragment of the HIV-1 gag/pol gene in two control and two clinical samples. The effect of PCR amplification was analysed. Error correction resulted in a two- and five-fold decrease of the pyrosequencing base substitution rate, from 0.05% to 0.03% and from 0.25% to 0.05% in the non-PCR and PCR-amplified samples, respectively. We were able to detect viral clones as rare as 0.1% with perfect sequence reconstruction. Probabilistic haplotype inference outperforms the counting-based calling method in both precision and recall. Genetic diversity observed within and between two clinical samples resulted in various patterns of phenotypic drug resistance and suggests a close epidemiological link. We conclude that pyrosequencing can be used to investigate genetically diverse samples with high accuracy if technical errors are properly treated. 相似文献
66.
Sabio y García JV Bigi F Rossetti O Campos E 《Microbes and infection / Institut Pasteur》2010,12(14-15):1236-1243
Immunodominant MPB83 antigen from Mycobacterium bovis was expressed as a chimeric protein fused to either β-galactosidase, outer membrane lipoprotein OMP19 or periplasmic protein BP26 in gram-negative Brucella abortus S19, in all cases driven by each gene's own promoter. All fusion proteins were successfully expressed and localized in the expected subcellular fraction. Moreover, OMP19-MPB83 was processed as a lipoprotein when expressed in B. abortus. Splenocytes from BALB/c mice immunized with the recombinant S19 strains carrying the genes coding for the heterologous antigens in replicative plasmids, showed equally specific INF-γ production in response to MPB83 stimulation. Association to the lipid moiety of OMP19 presented no advantage in terms of immunogenicity for MPB83. In contrast, fusion to BP26, which was encoded by an integrative plasmid, resulted in a weaker immune response. None of the constructions affected the survival rate or the infection pattern of Brucella. We concluded that B. abortus S19 is an appropriate candidate for the expression of M. bovis antigens both associated to the membrane or cytosolic fraction and may provide the basis for a future combined vaccine for bovine brucellosis and tuberculosis. 相似文献
67.
Aranapakam M. Venkatesan Zecheng Chen Osvaldo Dos Santos Christoph Dehnhardt Efren Delos Santos Semiramis Ayral-Kaloustian Robert Mallon Irwin Hollander Larry Feldberg Judy Lucas Ker Yu Inder Chaudhary Tarek S. Mansour 《Bioorganic & medicinal chemistry letters》2010,20(19):5869-5873
A series of mono-morpholino 1,3,5-triazine derivatives (8a–8q) bearing a 3-oxa-8-azabicyclo[3.2.1]octane were prepared and evaluated for PI3-kinase/mTOR activity. Replacement of one of the bis-morpholines in lead compound 1 (PKI-587) with 3-oxa-8-azabicyclo[3.2.1]octane and reduction of the molecular weight yielded 8m (PKI-179), an orally efficacious dual PI3-kinase/mTOR inhibitor. The in vitro activity, in vivo efficacy, and PK properties of 8m are discussed. 相似文献
68.
Angel Casacó Irene Beausoleil Bárbara Gonzalez Patricia Luaces Avelina León María E. Arteaga Pavel Prado Valia Rodríguez Aylén Pérez Grisel Guevara Ana M. Bada Nuris Ledón Dasha Fuentes Consuelo González Osvaldo Hernandez Romy Orphee Diuris Blanco Miriam García‐Osuma Alcides Ballester‐Labrada 《Journal of medical primatology》2010,39(3):177-186
Background The purpose of this study is to better characterize the hematological, biochemical, respiratory, cardiovascular and electroneurophysiological parameters in young adult Cercopithecus aethiops sabaeus of both sexes. The rhesus and cynomolgus monkeys are widely used as experimental primate models. However, only few articles have been published testing toxicological effects of pharmaceuticals on African green monkey. Methods The present study was carried out with the recompilation of all parameters recorded before the first drug administration in five sub‐chronic or chronic toxicological studies performed on 66 Cercopithecus aethiops sabaeus, born in Cuba. Results This study provides hematological, biochemical, respiratory, cardiovascular and electroneurophysiological data for both choosing animals to be included into experiments and monitoring these parameters during the study. Conclusions We conclude that this study provides valuable integrated data for determining the health status, including electroneurophysiological parameters, data not previously reported for this species, of the African green monkey. 相似文献
69.
Luiz Henrique Saes Zobiole Edicléia Aparecida Bonini Rubem Silvério de OliveiraJr. Robert John Kremer Osvaldo Ferrarese-Filho 《Acta Physiologiae Plantarum》2010,32(5):831-837
Farmers report that some glyphosate-resistant soybean varieties are visually injured by glyphosate. Glyphosate is the main
herbicide that directly affects the synthesis of secondary compounds. In this work, we evaluated the effect of increasing
rates of glyphosate on lignin and amino acid content, photosynthetic parameters and dry biomass in the early maturity group
cultivar BRS 242 GR soybean. Plants were grown in half-strength complete nutrient solution and subjected to various rates
of glyphosate either as a single or in sequential applications. All parameters evaluated were affected by increasing glyphosate
rates. The effects were more pronounced as glyphosate rates increased, and were more intense with a single total application
than sequential applications at lower rates. 相似文献
70.
Serra DO Lücking G Weiland F Schulz S Görg A Yantorno OM Ehling-Schulz M 《Proteomics》2008,8(23-24):4995-5010
Proteome analysis was combined with whole-cell metabolic fingerprinting to gain insight into the physiology of mature biofilm in Bordetella pertussis, the agent responsible for whooping cough. Recent reports indicate that B. pertussis adopts a sessile biofilm as a strategy to persistently colonize the human host. However, since research in the past mainly focused on the planktonic lifestyle of B. pertussis, knowledge on biofilm formation of this important human pathogen is still limited. Comparative studies were carried out by combining 2-DE and Fourier transform infrared (FT-IR) spectroscopy with multivariate statistical methods. These complementary approaches demonstrated that biofilm development has a distinctive impact on B. pertussis physiology. Results from MALDI-TOF/MS identification of proteins together with results from FT-IR spectroscopy revealed the biosynthesis of a putative acidic-type polysaccharide polymer as the most distinctive trait of B. pertussis life in a biofilm. Additionally, expression of proteins known to be involved in cellular regulatory circuits, cell attachment and virulence was altered in sessile cells, which strongly suggests a significant impact of biofilm development on B. pertussis pathogenesis. In summary, our work showed that the combination of proteomics and FT-IR spectroscopy with multivariate statistical analysis provides a powerful tool to gain further insight into bacterial lifestyles. 相似文献