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91.
Marina de Toledo Ferraz Dellias Clóvis Daniel Borges Mário Lúcio Lopes Sandra Helena da Cruz Henrique Vianna de Amorim Siu Mui Tsai 《Antonie van Leeuwenhoek》2018,111(9):1631-1644
Industrial ethanol fermentation is subject to bacterial contamination that causes significant economic losses in ethanol fuel plants. Chronic contamination has been associated with biofilms that are normally more resistant to antimicrobials and cleaning efforts than planktonic cells. In this study, contaminant species of Lactobacillus isolated from biofilms (source of sessile cells) and wine (source of planktonic cells) from industrial and pilot-scale fermentations were compared regarding their ability to form biofilms and their sensitivity to different antimicrobials. Fifty lactobacilli were isolated and the most abundant species were Lactobacillus casei, Lactobacillus fermentum and Lactobacillus plantarum. The majority of the isolates (87.8%) were able to produce biofilms in pure culture. The capability to form biofilms and sensitivity to virginiamycin, monensin and beta-acids from hops, showed inter- and intra-specific variability. In the pilot-scale fermentation, Lactobacillus brevis, L. casei and the majority of L. plantarum isolates were less sensitive to beta-acids than their counterparts from wine; L. brevis isolates from biofilms were also less sensitive to monensin when compared to the wine isolates. Biofilm formation and sensitivity to beta-acids showed a positive and negative correlation for L. casei and L. plantarum, respectively. 相似文献
92.
Deividi C. S. Soares José L. R. Portela Daniel H. Roos Nathane R. Rodrigues Karen K. Gomes Giulianna E. Macedo Thais Posser Jeferson L. Franco Waseem Hassan Robson L. Puntel 《Molecular and cellular biochemistry》2018,442(1-2):129-142
PTZ is a convulsive agent that acts via selective blockage of GABAA receptor channels, whereas 4-AP leads to a convulsive episode via blockage of K+ channels. However, the mechanism(s) by which pentylenetetrazole (PTZ) and 4-aminopyridine (4-AP) cause toxicity to Drosophila melanogaster needs to be properly explored, once it will help in establishing an alternative model for development of proper therapeutic strategies and also to counteract the changes associated with exposure to both epileptic drugs. For the purpose, we investigated the effects of exposure (48 h) to PTZ (60 mM) and/or 4-AP (20 mM) on survival, locomotor performance, and biochemical markers in the body and/or head of flies. 4-AP-fed flies presented a higher incidence of mortality and a worse performance in the open field test as compared to non-treated flies. 4-AP also caused a significant increase in the reactive species (RS) and protein carbonyl (PC) content in the body and head. Also a significant increase in catalase and acetylcholinesterase (AChE) activities was observed in the body. In the same vein, PTZ exposure resulted in a significant increase in RS, thiobarbituric acid reactive substances (TBARS), PC content, and catalase activity in the body. PTZ exposure also caused a significant increase in AChE activity both in body and head. It is important to note that PTZ-treated flies also down-regulated the NRF2 expression. Moreover, both 4AP- and PTZ-fed flies presented a significant decrease in MTT reduction, down-regulation, and inhibition of SOD in body. However, SOD was significantly more active in the head of both 4-AP and PTZ-treated flies. Our findings provide evidence regarding the toxicological potential of both PTZ and/or 4-AP to flies. This model will help in decoding the underlying toxicological mechanisms of the stated drugs. It will also help to properly investigate the therapeutic strategies and to counteract the drastic changes associated with both epileptogenic drugs. 相似文献
93.
Cunha Joana T. Costa Carlos E. Ferraz Luís Romaní Aloia Johansson Björn Sá-Correia Isabel Domingues Lucília 《Applied microbiology and biotechnology》2018,102(10):4589-4600
Applied Microbiology and Biotechnology - Acetic acid tolerance and xylose consumption are desirable traits for yeast strains used in industrial biotechnological processes. In this work,... 相似文献
94.
Maria Luiza S. Mello Flvia S. Kubrusly M. A. F. Randi Vera Lúcia C. C. Rodrigues A. N. Ferraz Filho 《Entomologia Experimentalis et Applicata》1995,74(3):209-218
The nuclear phenotypes and survival of the hemipteran,Triatoma infestans (Hemiptera, Reduviidae), were studied in specimens treated with copper sulfate and methylmercury. The objective was to determine
whether changes in chromatin supraorganization and insect survival similar to those promoted by other stressing agents could
also be induced by heavy metals. At the concentrations used, copper sulfate and methylmercury were toxic to the cells, mainly
inducing nuclear degenrration in the Malpighian tubules and being lethal to a large part of the insect population. Although
some individual resistance was found, especially in fasted specimens, heavy metals were found to be much more lethal than
was, for instance, a thermal shock at 0°C for 12 h. The nuclear phenotypes detected after heavy metal treatment were similar
to those reported under other stressing conditions. However, the frequency at which nuclei exhibited aspects of heterochromatin
unraveling was much higher than that found in fasted and thermal-shocked specimens, and was independent of the heavy metal
type used. If this phenotype represents an attempt to improve opportunities for extensive cell and insect survival, it was
not sufficiently effective. In 5th instar nymphs, the effect of CuSO4 on chromatin supraorganization was detected at early steps of spermatogenesis but not in the cells which were at late spermiogenesis
when the metal was administered. This is probably due to changes in nuclear protein composition and to the tightly packed
state of the DNA-protein complexes occurring at spermiogenesis, which may protect chromatin from damages. However, when CuSO4 was supplied to 4th instar nymphs, it slowed down the spermiogenesis process, possibly due to several factors including Cu2+ binding to DNA phosphates. 相似文献
95.
The integration of alien plants in mutualistic plant–hummingbird networks across the Americas: the importance of species traits and insularity
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Pietro K. Maruyama Jeferson Vizentin‐Bugoni Jesper Sonne Ana M. Martín González Matthias Schleuning Andréa C. Araujo Andrea C. Baquero Juliana Cardona Paola Cardona Peter A. Cotton Glauco Kohler Carlos Lara Tiago Malucelli Oscar Humberto Marín‐Gómez Jeff Ollerton Ana M. Rui Allan Timmermann Isabela G. Varassin Thais B. Zanata Carsten Rahbek Marlies Sazima Bo Dalsgaard 《Diversity & distributions》2016,22(6):672-681
96.
97.
Francini?K.?J.?Yatsu Greice?S.?Borghetti Fagner?Magalh?es Humberto?G.?Ferraz Eloir?Paulo?Schenkel Valquiria?L.?BassaniEmail author 《AAPS PharmSciTech》2016,17(2):358-367
Several studies have shown the potential use of Ilex paraguariensis in developing products with the aim to protect biological systems against oxidative stress-mediated damages. In the same way, technological studies have demonstrated the feasibility of obtaining dry products, by spray-drying process, from aqueous extracts of I. paraguariensis in laboratory. The present work was designed to develop pellets by extrusion/spheronization process, from an I. paraguariensis spray-dried powder. The pellets were characterized with respect to their chemical, physical, and technological properties, and the thermal and the photostability of the main polyphenol constituents were investigated. The pellets exhibited adequate size, shape, and high process yield (78.7%), as well as a good recovery of the total polyphenols (>95%) and a good dissolution in water (89.44 to 100.05%). The polyphenols were stable against light when conditioned in amber glass bottles; unstable against heat when the samples were conditioned either in open glass bottles or in hermetically sealed glass bottles and demonstrated to be hygroscopic and sensible to the temperature, especially when stored in permeable flasks. These findings pointed to the relevance of reducing the residual moisture content of pellets as well as of conditioning them in opaque humidity tight packages under low temperatures. The feasibility of obtaining pellets from an I. paraguariensis spray-dried powder using extrusion/spheronization technique was, for the first time, demonstrated. This finding represents a novelty for the herbal products in both pharmaceutical and food fields. 相似文献
98.
Hercules R. Freitas Gabriel Ferraz Gustavo C. Ferreira Victor T. Ribeiro-Resende Luciana B. Chiarini José Luiz M. do Nascimento Karen Renata H. Matos Oliveira Tiago de Lima Pereira Leonardo G. B. Ferreira Regina C. Kubrusly Robson X. Faria Anderson Manoel Herculano Ricardo A. de Melo Reis 《PloS one》2016,11(4)
Neuroglia interactions are essential for the nervous system and in the retina Müller cells interact with most of the neurons in a symbiotic manner. Glutathione (GSH) is a low-molecular weight compound that undertakes major antioxidant roles in neurons and glia, however, whether this compound could act as a signaling molecule in neurons and/or glia is currently unknown. Here we used embryonic avian retina to obtain mixed retinal cells or purified Müller glia cells in culture to evaluate calcium shifts induced by GSH. A dose response curve (0.1–10mM) showed that 5–10mM GSH, induced calcium shifts exclusively in glial cells (later labeled and identified as 2M6 positive cells), while neurons responded to 50mM KCl (labeled as βIII tubulin positive cells). BBG 100nM, a P2X7 blocker, inhibited the effects of GSH on Müller glia. However, addition of DNQX 70μM and MK-801 20μM, non-NMDA and NMDA blockers, had no effect on GSH calcium induced shift. Oxidized glutathione (GSSG) at 5mM failed to induce calcium mobilization in glia cells, indicating that the antioxidant and/or structural features of GSH are essential to promote elevations in cytoplasmic calcium levels. Indeed, a short GSH pulse (60s) protects Müller glia from oxidative damage after 30 min of incubation with 0.1% H2O2. Finally, GSH induced GABA release from chick embryonic retina, mixed neuron-glia or from Müller cell cultures, which were inhibited by BBG or in the absence of sodium. GSH also induced propidium iodide uptake in Müller cells in culture in a P2X7 receptor dependent manner. Our data suggest that GSH, in addition to antioxidant effects, could act signaling calcium shifts at the millimolar range particularly in Müller glia, and could regulate the release of GABA, with additional protective effects on retinal neuron-glial circuit. 相似文献
99.
Biodegradation of softwood ( Pinus radiata ) by the ascomycete Chrysonilia sitophila was dependent on the nitrogen and glucose concentrations in the culture medium. Optimization studies of the delignification process, in which the nitrogen (0–50mmol/l NH+ 4 ) and glucose (0–2%) concentrations were varied, showed a maximal value of 17·8% for sawdust degradation in cultures containing 10 mmol/l NH4 + and 1·0% glucose. Solubility of the decayed sawdust in 1% NaOH at maximal delignification conditions showed a threefold increase and changes in the thermogravimetric pattern were also observed. Biodegraded wood chips showed significant decreases of the 280 and 310 nm characteristic lignin bands in the u.v. reflectance spectra. 相似文献
100.
C A Ferraz de Carvalho 《Acta anatomica》1987,129(1):15-21
The elastic, elaunin and oxytalan fibres in the tunica mucosa and tela submucosa of veins of the human lower oesophagus were studied in 30 necropsy and biopsy specimens using appropriate histological and ultrastructural methodologies. Elaunin fibres predominate in the veins endowed with muscle cells. Scattered oxytalan and elastic fibres were also observed, the latter being more numerous at the vein periphery. No noteworthy fibre arrangement was encountered in veins lacking muscle cells. Those fibres disposed around the veins were considered to belong to the connective tissue of the tunica mucosa and tela submucosa in which they are embedded. The veins of the lower oesophagus seem to be of low elasticity, which may be related to a blockage mechanism described for the gastro-oesophageal blood stream in cases of portal hypertension. 相似文献