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991.
992.
Oscar Dias Thiago O. Basso Isabel Rocha Eugénio C. Ferreira Andreas K. Gombert 《Antonie van Leeuwenhoek》2018,111(2):183-195
The yeast Kluyveromyces lactis has received attention both from academia and industry due to some important features, such as its capacity to grow in lactose-based media, its safe status, its suitability for large-scale cultivation and for heterologous protein synthesis. It has also been considered as a model organism for genomics and metabolic regulation. Despite this, very few studies were carried out hitherto under strictly controlled conditions, such as those found in a chemostat. Here we report a set of quantitative physiological data generated during chemostat cultivations with the K. lactis CBS 2359 strain, obtained under glucose-limiting and fully aerobic conditions. This dataset serve as a basis for the comparison of K. lactis with the model yeast Saccharomyces cerevisiae in terms of their elemental compositions, as well as for future metabolic flux analysis and metabolic modelling studies with K. lactis. 相似文献
993.
994.
Mariana Volpe Arnoni Claudete Rodrigues Paula Marcos Ereno Auler Cirilo Cesar Naozuka Simões Shirley Nakano Maria Walderez Szeszs Márcia de Souza Carvalho Melhem Virgínia Bodelão Richini Pereira Hans Garcia Garces Eduardo Bagagli Eriques Gonçalves Silva Melissa Ferreira de Macêdo Luciana da Silva Ruiz 《Mycopathologia》2018,183(6):941-949
Fusarium species have emerged as responsible for a broad spectrum of infections, including superficial, locally invasive and disseminated ones, especially in the hospital environment. Since there are few reports of invasive and disseminated fusariosis in children, the aim of this study was to report four cases of nosocomial infection caused by this microorganism in children with cancer hospitalized in a public children’s hospital located in Brazil. Two of these patients were female and two were male. All patients presented febrile neutropenia, while three patients had acute lymphocytic leukemia and one patient had Wilms’ tumor as underlying disease. In two cases, fungi were isolated from blood and identified as Fusarium oxysporum species complex after phenotypic and genotypic studies, while in two other cases fungi were isolated from skin biopsies and identified as Fusarium solani species complex. One patient died 12 days after the onset of cutaneous lesions. All isolates, after susceptibility testing, presented high levels of minimum inhibitory concentration for itraconazole, voriconazole and amphotericin B. Considering the emergence of filamentous fungi as etiologic agents of nosocomial infections, health professionals should be aware of the problems these infections, especially fungal ones, may cause to debilitated patients. 相似文献
995.
Linette Kadri Romain Ferru-Clément Amélie Bacle Laurie-Anne Payet Anne Cantereau Reynald Hélye Frédéric Becq Christophe Jayle Clarisse Vandebrouck Thierry Ferreira 《生物化学与生物物理学报:疾病的分子基础》2018,1864(9):3069-3084
Maintaining the equilibrium between saturated and unsaturated fatty acids within membrane phospholipids (PLs) is crucial to sustain the optimal membrane biophysical properties, compatible with selective organelle-based processes. Lipointoxication is a pathological condition under which saturated PLs tend to accumulate within the cell at the expense of unsaturated species, with major impacts on organelle function. Here, we show that human bronchial epithelial cells extracted from lungs of patients with Obstructive Pulmonary Diseases (OPDs), i. e. Cystic Fibrosis (CF) individuals and Smokers, display a characteristic lipointoxication signature, with excessive amounts of saturated PLs. Reconstitution of this signature in cellulo and in silico revealed that such an imbalance results in altered membrane properties and in a dramatic disorganization of the intracellular network of bronchial epithelial cells, in a process which can account for several OPD traits. Such features include Endoplasmic Reticulum-stress, constitutive IL8 secretion, bronchoconstriction and, ultimately, epithelial cell death by apoptosis. We also demonstrate that a recently-identified lipid-like molecule, which has been shown to behave as a “membrane-reshaper”, counters all the lipointoxication hallmarks tested. Altogether, these insights highlight the modulation of membrane properties as a potential new strategy to heal and prevent highly detrimental symptoms associated with OPDs. 相似文献
996.
Global change, including invasive species introduction, has already had observable effects on migrant bird species, from northern breeding areas to wintering grounds. In this study we analyze the response of the Eurasian oystercatcher abundance to the density of an invasive clam species (Corbicula fluminea) and its potential role as biological control. As a case study, the oystercatcher population fluctuations over a 30‐yr time period, coupled with video‐recorded estimates of its feeding behavior on C. fluminea, and results from an exclosure experiment, were analyzed in the NW of the Iberian Peninsula. Results showed that oystercatchers exert a top‐down control over C. fluminea density. In addition, oystercatchers doubled its wintering numbers in a C. fluminea invaded estuary where they actively feed upon this invasive clam. Given that, the facilitative interaction between the invasive C. fluminea and the migratory Eurasian oystercatcher seems to respond to bottom‐up forces. Altogether, our results suggest that control measures applied to long term biological invasions must be carefully analyzed since non‐native species may be sustaining dependent native communities. 相似文献
997.
Raiza Brandão Peres Asma Inam Ullah Ludmila Ferreira de Almeida Fiuza Patricia Bernardino Silva Marcos M. Batista Olivia Corcoran Tummala Rama Krishna Reddy Maria de Nazaré Correia Soeiro 《Bioorganic & medicinal chemistry letters》2018,28(11):2018-2022
Chagas disease is a neglected pathology responsible for about 12,000 deaths every year across Latin America. Although six million people are infected by the Trypanosoma cruzi, current therapeutic options are limited, highlighting the need for new drugs. Here we report the preliminary structure activity relationships of a small library of 17 novel pyridyl sulfonamide derivatives. Analogues 4 and 15 displayed significant potency against intracellular amastigotes with EC50 of 5.4?µM and 8.6?µM. In cytotoxicity assays using mice fibroblast L929 cell lines, both compounds indicated low toxicity with decent selectivity indices (SI) >36 and?>23 respectively. Hence these compounds represent good starting points for further lead optimization. 相似文献
998.
Attraction and vibration: Effects of previous exposure and type of food resource in the perception of allocolonial odors in termites 下载免费PDF全文
Dinamarta V. Ferreira Paulo F. Cristaldo Marcos L. C. Rocha Daniela L. Santana Lucineide Santos Paulo S. S. Lima Ana P. A. Araújo 《Ethology : formerly Zeitschrift fur Tierpsychologie》2018,124(10):743-750
Social insects have an efficient recognition system that guarantees social cohesion and protection against intruders in their colonies and territories. However, the energy costs in constant conflicts with neighboring colonies could promote a reduction in the fitness of colonies. Here, we evaluated the effect of previous exposure to allocolonial odor and the consumption of similar food resources on aggressive behavior and choice of allocolonial cues in Nasutitermes aff. coxipoensis (Termitidae: Nasutitermitinae). Our results showed that intercolonial aggressiveness was not affected by previous exposure to allocolonial odor and by the consumption of similar food resources. However, individuals previously exposed to allocolonial odor were more attracted to these odors than individuals who had no prior exposure to allocolonial odor. In addition, individuals from colonies of N. aff. coxipoensis that use similar food resources increased alertness via a greater number of vibration than individuals who consumed different food resources. In general, our results indicate that colonies of N. aff coxipoensis perceive allocolonial cues that have been previously exposed and that the consumption of similar resources triggers an alert signal between individuals. Additional studies are necessary to assess how widespread this capacity of perception is present among the different Isoptera groups and the consequences of colony recognition odor cues on termite space use. 相似文献
999.
Population parameters and reproduction of the piranha Serrasalmus marginatus in the Negro river,Pantanal, Brazil 下载免费PDF全文
Wagner Vicentin Karina Keyla Tondato Fabiane Silva Ferreira Fábio Edir dos Santos Costa Yzel Rondon Súarez 《Zeitschrift fur angewandte Ichthyologie》2018,34(5):1136-1144
This paper aimed to define the reproductive period and population parameters of Serrasalmus marginatus relative to local environmental features, such as day length, rainfall and mean river level. The study site was a floodplain in the Negro river, Pantanal, Brazil, and samples were collected bimonthly using gill nets and cast nets with meshes from 1.5 to 8 cm between adjacent knots. The reproduction period, as determined by gonadosomatic index (GSI) and percentage of gonad stages, varied significantly along the year (F4,116 = 77.5; p < 0.01), but it was well defined from October to December. Reproduction period was positively correlated with rainfall (rs = 0.97; p < 0.01) and photoperiod (rs = 0.92; p = 0.02), but not with the rise of river level (rs = 0.10; p = 0.86). Rainfall and photoperiod may act as predictive factors, providing cues to fish to begin reproduction in order to find the best conditions for offspring in the following months, during the flooding season, when the river level reaches its peak and extends to the plain. We have herein reported the first population parameters described for this species in the Brazilian Pantanal, including growth rate (k = 0.53/year), asymptotic length (L∞ = 32.74), lifespan (A0.95 = 5.65) and mortality (M = 1.11), showing that this population has better growth performance when compared to data reported for this same species in the Paraná river since the population in the Negro river is characterized by lower growth and mortality rates, and S. marginatus achieved longer lengths and lifespan. This latter parameter was compatible with six cohorts estimated by Electronic Length Frequency Analysis (ELEFAN). The size at first maturity (L50 = 18.26 cm A50 = 1.56 years) was also larger and later than the population in the Paraná river, likely a consequence of the the lower mortality and the maintenance of larger specimens in the Negro river. 相似文献
1000.
L.-T. Dinis A. C. Malheiro A. Luzio H. Fraga H. Ferreira I. Gonçalves G. Pinto C. M. Correia J. Moutinho-Pereira 《Photosynthetica》2018,56(2):641-651
Knowledge about short-term climate change adaptation strategies for Mediterranean vineyards is needed in order to improve grapevine physiology and yield-quality attributes. We investigated effects of kaolin-particle film suspension on water relations, photosynthesis and oxidative stress of field-grown grapevines in the Douro region (northern Portugal) in 2012 and 2013. Kaolin suspension decreased leaf temperature by 18% and increased leaf water potential (up to 40.7% in 2013). Maximum photochemical quantum efficiency of PSII was higher and the minimal chlorophyll fluorescence was lower in the plants sprayed by kaolin. Two months after application, net photosynthesis and stomatal conductance at midday increased by 58.7 and 28.4%, respectively, in treated plants. In the same period, kaolin treatment increased photochemical reflectance, photosynthetic pigments, soluble proteins, soluble sugars, and starch concentrations, while decreased total phenols and thiobarbituric acid-reactive substances. Kaolin application can be an operational tool to alleviate summer stresses, which ameliorates grapevine physiology and consequently leads to a higher yield. 相似文献