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661.
Irene Anastasia Nicolò Ilacqua Andrea Raimondi Philippe Lemieux Rana Ghandehari-Alavijeh Guilhem Faure Sergei L. Mekhedov Kevin J. Williams Federico Caicci Giorgio Valle Marta Giacomello Ariel D. Quiroga Richard Lehner Michael J. Miksis Katalin Toth Thomas Q. de Aguiar Vallim Eugene V. Koonin Luca Scorrano Luca Pellegrini 《Cell reports》2021,34(11):108873
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662.
Julia Penna Coutinho Anna Caroline Campos Aguiar Pierre Alexandre dos Santos Joaquim Corsino Lima Maria Gabrielle Lima Rocha Carlos Leomar Zani Tania Maria Almeida Alves Ant?nio Euzébio Goulart Santana Maria de Meneses Pereira Antoniana Ursine Krettli 《Memórias do Instituto Oswaldo Cruz》2013,108(8):974-982
Infusions of Aspidosperma nitidum (Apocynaceae) wood bark are used
to treat fever and malaria in the Amazon Region. Several species of this family are
known to possess indole alkaloids and other classes of secondary metabolites, whereas
terpenoids, an inositol and the indole alkaloids harmane-3 acid and braznitidumine
have been described in A. nitidum . In the present study, extracts
from the wood bark, leaves and branches of this species were prepared for assays
against malaria parasites and cytotoxicity testing using human hepatoma and normal
monkey kidney cells. The wood bark extracts were active against Plasmodium
falciparum and showed a low cytotoxicity in vitro, whereas the leaf and
branch extracts and the pure alkaloid braznitidumine were inactive. A crude methanol
extract was subjected to acid-base fractionation aimed at obtaining alkaloid-rich
fractions, which were active at low concentrations against P.
falciparum and in mice infected with and sensitive Plasmodium
berghei parasites. Our data validate the antimalarial usefulness of
A. nitidum wood bark, a remedy that can most likely help to
control malaria. However, the molecules responsible for this antimalarial activity
have not yet been identified. Considering their high selectivity index, the
alkaloid-rich fractions from the plant bark might be useful in the development of new
antimalarials. 相似文献
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666.
Danielle Caroline Manenti Jackson Araújo Matheus Hideki Kihara Maeda Moana Lima Tavares-Esashika Paulo Hugo Aguiar Anderson Rotter Meda Tatsuya Nagata Eliezer Rodrigues de Souto 《The Annals of applied biology》2023,182(2):216-225
Cotton blue disease (CBD) and atypical-CBD are the most important viral diseases of cotton plants in the southern region of South America. Common and atypical strains of cotton leafroll dwarf virus (CLRDV and CLRDV-at, respectively) are thought to be causative agents of CBD and atypical-CBD, respectively. Inoculation of test plants via aphid vectors is difficult, as is determining strains via molecular diagnosis; accordingly, it is difficult for breeders to evaluate the effects of blue disease-associated virus infections in cotton lineages. In the present study, we attempted to circumvent these difficulties by producing six full-length cDNA infectious clones from CLRDV and CLRDV-at strains using the Gibson Assembly protocol. For inoculation of the infectious clones, a vacuum chamber-mediated agroinfiltration protocol was adapted and applied. Using this protocol, 90%–100% of cotton plants became infected with the clones, which was not possible via syringe-based agroinfiltration. A genotyping protocol based on RT-qPCR targeting a specific region of the virus P0 protein was also developed, allowing rapid differentiation of CLRDV and CLRDV-at. Applying this protocol to 68 field samples revealed that CLRDV-at was dominant (50%) over CLRDV (5.8%) in single virus infections. These preliminary results imply that CLRDV-at might occupy the ecological niche of CLRDV in the cotton fields of Brazil. 相似文献
667.
Luiz Fernando Ferreira Mario Aguiar Georgia Pompeu Tâmara Guido Messias Regina Rosim Monteiro 《World journal of microbiology & biotechnology》2010,26(9):1613-1621
Vinasse is a highly colored effluent with a high pollutant potential when disposed in the environment. Assays for decolorization
of vinasse were performed, selecting the fungus Pleurotus sajor-caju CCB 020. The discoloration was cocominant with the increase of the activities of laccase, manganese-peroxidase and peroxidases.
P. sajor-caju demonstrated a rise in biomass production (1.06 g 100 ml−1), and the enzyme activities such as laccase (varying from 400 to 450 IU l−1) reached between the 9th and 10th day of growth and for MnP at the 12th day of cultivation (varying from 60 to 100 IU l−1). It was concluded that the system P. sajor-caju/vinasse can be utilized as a bioprocess for color removal and degradation of complex vinasse compounds. It was observed an
improvement in the characteristics and detoxification allowing its utilization as reused water, laccase and manganese-peroxidase
enzymes production and for fungal biomass production with a high nutritional value. 相似文献
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669.
We experimentally and theoretically investigated the persistence of hosts and parasitoids interacting in a metapopulation structure consisting of ephemeral local patches (MELPs). We used a host–parasitoid system consisting of necrophagous Diptera species and their pupal parasitoids. The basal resources used by the host species were assumed to be ephemeral, supporting only one generation of individuals before completely disappearing from the environment. We experimentally measured the host–parasitoid persistence and the effects of local demographic processes in two scenarios: 1) constant occurrence of basal resources at a single site (no dispersion or colonization of other sites) and 2) variable occurrence of basal resources between two sites (colonization of a new patch requiring species dispersal). The experimental setup and findings were then formalized into a mathematical model describing the interaction dynamics in a MELP structure. We evaluated the contribution of several factors to the host–parasitoid coexistence, such as resource allocation probability (probability of resource appearance in a site), variation in resource size and number of sites available to receive resources in the MELP. We found that demographic fluctuations and environmental stochasticity affected the density of migrants, patch habitat connectivity, persistence and spatial distribution of interacting species. 相似文献
670.
F. R. SCARANO FLS H. M. DUARTE G. RÔÇAS S. M. B. BARRETO E. F. AMADO F. REINERT T. WENDT A. MANTOVANI H. R. P. LIMA C. F. BARROS 《Botanical journal of the Linnean Society. Linnean Society of London》2002,140(4):391-401
The clonal tank-bromeliad Aechmea bromeliifolia (Rudge) Baker was found in four different habitats in a restinga (vegetation mosaic on sandy coastal plains), of south-eastern Brazil. These habitats (swamp forest, dry forest, dry shrubland and herbaceous marsh) lie within a few hundred metres of each other along a gradient extending inland from the coast, and differ markedly in terms of light and flood regime. We compared ramet morphology, leaf anatomy and physiology, and population parameters to examine the amplitude of trait variation of this widespread species in the studied restinga. This integrated approach allowed us to examine which variation conferred acclimation and which was merely a stress symptom. A . bromeliifolia showed site-specific differences in abundance, distribution, rosette size and shape, leaf anatomical arrangement and photochemical efficiency (potential quantum yield; F v / F m ) during the day. Most of the variation found seemed to be related to the interaction of light and flooding. The lowest number and size of ramets at the exposed, dry shrubland was matched by a marked leaf photoinhibition, which suggested poor acclimation to local levels of light intensity and limited water supply. In the other habitats, the morpho-physiological parameters measured suggested adequate foraging behaviour and site acclimation. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society, 2002, 140 , 391-401. 相似文献