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111.
Nicolli Bellotti de Souza Isabel M de Andrade Paula F Carneiro Guilherme AM Jardim Isadora MM de Melo Eufranio N da Silva Júnior Antoniana Ursine Krettli 《Memórias do Instituto Oswaldo Cruz》2014,109(5):546-552
Due to the recent advances of atovaquone, a naphthoquinone, through clinical trials
as treatment for malarial infection, 19 quinone derivatives with previously reported
structures were also evaluated for blood schizonticide activity against the malaria
parasite Plasmodium falciparum. These compounds include 2-hydroxy-3-methylamino
naphthoquinones (2-9), lapachol (10), nor-lapachol (11), iso-lapachol (12), phthiocol
(13) and phenazines (12-20). Their cytotoxicities were also evaluated against human
hepatoma and normal monkey kidney cell lines. Compounds 2 and 5 showed the highest
activity against P. falciparum chloroquine-resistant blood-stage parasites (clone
W2), indicated by their low inhibitory concentration for 50% (IC50) of
parasite growth. The therapeutic potential of the active compounds was evaluated
according to the selectivity index, which is a ratio of the cytotoxicity minimum
lethal dose which eliminates 50% of cells and the in vitro IC50.
Naphthoquinones 2 and 5, with activities similar to the reference antimalarial
chloroquine, were also active against malaria in mice and suppressed parasitaemia by
more than 60% in contrast to compound 11 which was inactive. Based on their in vitro
and in vivo activities, compounds 2 and 5 are considered promising molecules for
antimalarial treatment and warrant further study. 相似文献
112.
Camila Carlos Mathias M Pires Nancy C Stoppe Elayse M Hachich Maria IZ Sato Tânia AT Gomes Luiz A Amaral Laura MM Ottoboni 《BMC microbiology》2010,10(1):161
Background
Escherichia coli strains are commonly found in the gut microflora of warm-blooded animals. These strains can be assigned to one of the four main phylogenetic groups, A, B1, B2 and D, which can be divided into seven subgroups (A0, A1, B1, B22, B23, D1 and D2), according to the combination of the three genetic markers chuA, yjaA and DNA fragment TspE4.C2. Distinct studies have demonstrated that these phylo-groups differ in the presence of virulence factors, ecological niches and life-history. Therefore, the aim of this work was to analyze the distribution of these E. coli phylo-groups in 94 human strains, 13 chicken strains, 50 cow strains, 16 goat strains, 39 pig strains and 29 sheep strains and to verify the potential of this analysis to investigate the source of fecal contamination. 相似文献113.
The anti-algal activity of five macrophyte extracts on the cyanobacterium Microcystis aeruginosa in Egypt was investigated in 2013. Extract activity varied according to plant type, extracting solvent and its concentration. The highest inhibitory activity was achieved with ethanol extract at a concentration of 80 mg l?1, followed by chloroformic extracts, at 60 mg l?1. Methanolic extracts of Eichhornia crassipes and Polygonum tomentosum inhibited growth of Microcystis aeruginosa at all concentrations. Acetonic extracts inhibited algal growth at 60 mg l?1, except for the extract of Ceratophyllum subdemersum, which showed stimulation of M. aeruginosa growth. Eichhornia crassipes ethanolic extract exerted the most powerful inhibition by more than five-fold, 570.17%, followed by those of P. tomentosum, Saccharum spontaneum, Ceratophyllum demersum and C. subdemersum, 559.48, 553.99, 544.11 and 366.51%, respectively. Phytochemical screening for the tested plant extracts revealed the presence of biologically active substances of different concentrations, with P. tomentosum having the highest polyphenols, 1.95% of dry weight. 相似文献
114.
115.
This paper unfolds the events, the people and the times that led up to the
founding of AChemS and fashioned its character during its early formative
years. It describes the path over which AChemS came, going from the
original assertions and denials for the need of such an organization to its
later inception and nascent development. This narration highlights such
topics as the debate over the need for AChemS, the role of National Science
Foundation in the founding of AChemS, the derivation of the Association's
name, the choice of Sarasota and the Hyatt House as the meeting site, the
generation of the programs for the early annual meetings, the adoption of
the bylaws, the process of incorporation and tax deferment, and the birth
of the Givaudan Lectureship. Most emphatically highlighted, however, is the
enthusiasm, commitment and hard work that the members of the chemosensory
research community displayed in bringing AChemS to fruition.
相似文献
116.
Nicole Walch Theresa Scharl Edit Felfldi Dominik G. Sauer Michael Melcher Friedrich Leisch Astrid Dürauer Alois Jungbauer 《Biotechnology journal》2019,14(7)
Regulatory recommendations for quality by design instead of quality by testing raise increasing interest in new sensor technologies. An online monitoring system for downstream processes is developed, which is based on an array of online detectors. Besides standard detectors (UV, pH, and conductivity), our chromatographic workstation is equipped with a fluorescence and a mid‐infrared spectrometer, a light scattering, and a refractive index detector. The combination of these sensors enables the prediction of specific protein concentration and various purity attributes, such as high molecular weight impurities, DNA and host cell protein content during the elution phase of a chromatographic antibody capture process. Prediction models solely based on online signals are set up providing real‐time predictions. No mechanistic models or information about the chromatographic runs is used. These predictions allow online pooling decisions replacing time‐ and labor‐intensive laboratory measurements. Different process variations, such as changes in the column load or elution buffer, are introduced to test the predictive power of the models. Extrapolation of the models worked well when the column load is changed, whereas model adjustment is necessary when the elution conditions are changed considerably. 相似文献