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1.
Sci Rep ; 13(1): 12491, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528129

RESUMO

Animal venoms are rich sources of neuroactive compounds, including anti-inflammatory, antiepileptic, and antinociceptive molecules. Our study identified a protonectin peptide from the wasp Parachartergus fraternus' venom using mass spectrometry and cDNA library construction. Using this peptide as a template, we designed a new peptide, protonectin-F, which exhibited higher antinociceptive activity and less motor impairment compared to protonectin. In drug interaction experiments with naloxone and AM251, Protonectin-F's activity was decreased by opioid and cannabinoid antagonism, two critical antinociception pathways. Further experiments revealed that this effect is most likely not induced by direct action on receptors but by activation of the descending pain control pathway. We noted that protonectin-F induced less tolerance in mice after repeated administration than morphine. Protonectin-F was also able to decrease TNF-α production in vitro and modulate the inflammatory response, which can further contribute to its antinociceptive activity. These findings suggest that protonectin-F may be a potential molecule for developing drugs to treat pain disorders with fewer adverse effects. Our results reinforce the biotechnological importance of animal venom for developing new molecules of clinical interest.


Assuntos
Peptídeos , Venenos de Vespas , Camundongos , Animais , Venenos de Vespas/química , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Morfina/farmacologia , Analgésicos Opioides , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Dor/tratamento farmacológico , Analgésicos/farmacologia , Analgésicos/uso terapêutico
2.
Front Mol Biosci ; 10: 1073721, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36950526

RESUMO

The cotton boll weevil (CBW) (Anthonomus grandis) is one of the major insect pests of cotton in Brazil. Currently, CBW control is mainly achieved by insecticide application, which is costly and insufficient to ensure effective crop protection. RNA interference (RNAi) has been used in gene function analysis and the development of insect control methods. However, some insect species respond poorly to RNAi, limiting the widespread application of this approach. Therefore, nanoparticles have been explored as an option to increase RNAi efficiency in recalcitrant insects. Herein, we investigated the potential of chitosan-tripolyphosphate (CS-TPP) and polyethylenimine (PEI) nanoparticles as a dsRNA carrier system to improve RNAi efficiency in the CBW. Different formulations of the nanoparticles with dsRNAs targeting genes associated with juvenile hormone metabolism, such as juvenile hormone diol kinase (JHDK), juvenile hormone epoxide hydrolase (JHEH), and methyl farnesoate hydrolase (MFE), were tested. The formulations were delivered to CBW larvae through injection (0.05-2 µg), and the expression of the target genes was evaluated using RT-qPCR. PEI nanoparticles increased targeted gene silencing compared with naked dsRNAs (up to 80%), whereas CS-TPP-dsRNA nanoparticles decreased gene silencing (0%-20%) or led to the same level of gene silencing as the naked dsRNAs (up to 50%). We next evaluated the effects of targeting a single gene or simultaneously targeting two genes via the injection of naked dsRNAs or dsRNAs complexed with PEI (500 ng) on CBW survival and phenotypes. Overall, the gene expression analysis showed that the treatments with PEI targeting either a single gene or multiple genes induced greater gene silencing than naked dsRNA (∼60%). In addition, the injection of dsJHEH/JHDK, either naked or complexed with PEI, significantly affected CBW survival (18% for PEI nanoparticles and 47% for naked dsRNA) and metamorphosis. Phenotypic alterations, such as uncompleted pupation or malformed pupae, suggested that JHEH and JHDK are involved in developmental regulation. Moreover, CBW larvae treated with dsJHEH/JHDK + PEI (1,000 ng/g) exhibited significantly lower survival rate (55%) than those that were fed the same combination of naked dsRNAs (30%). Our findings demonstrated that PEI nanoparticles can be used as an effective tool for evaluating the biological role of target genes in the CBW as they increase the RNAi response.

3.
Front Vet Sci ; 10: 1032429, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937008

RESUMO

A better understanding of the nutritional requirements of sheep, especially in terms of minerals, is crucial for improving production. We estimated the net requirements for Ca, P, K, Mg, and Na for gain (NCag, NPg, NKg, NMgg, and NNag) and maintenance (NCam, NPm, NKm, NMgm, and NNam) in male and female hair sheep. Six datasets with 248 individual records of hair sheep (139 non-castrated males, 75 castrated males and 34 females) were used to estimate the net macromineral requirements for gain. To estimate the net macromineral requirements for maintenance, 52 observations (26 non-castrated and 26 castrated males) were used. A meta-analytical approach was applied, using non-linear mixed effects models and the study as a random effect. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe mineral requirements with a low level of model selection uncertainty. The adopted criteria allowed the choice of the best models to represent the macromineral requirements. The chosen models explained the observed variability in the sex, and the choices were based on a low level of uncertainty (w ≥ 0.90). Irrespective of sex, NCag and NPg decreased with increasing BW from 10 to 30 kg and average daily gain (ADG) of 150 g/day, ranging from 1.71-1.38; 1.83-1.57; 1.82-1.51 of Ca and 0.86-0.66; 0.92-0.78; 0.92-0.75 of P for non-castrated males, castrated males, and females, respectively. The NKg remained constant, with mean values of 0.26 g/day. The NNag range was 0.17 to 0.14 g/day for non-castrated males, 0.20 to 0.25 g/day for females, and constant (0.18 g/day) for castrated males with an increase in BW from 10 to 30 kg and an ADG of 150 g/day. Macromineral requirements for maintenance (mg/kg BW) and retention (%) were 23.70 and 54.30 for Ca, 25.33 and 79.80 for P, 11.74 and 5.00 for K, 2.63 and 8.50 for Mg, and 7.01 and 8.10 for Na for males. The International Committees did not provide inferences about the sex influence on mineral requirements. Our study indicates that sex is one factor that influences the macromineral requirements for gain. The information generated in this study can be used to optimize the mineral management of hair sheep in the growing phase in tropical regions.

4.
Insects ; 12(12)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34940218

RESUMO

The coffee leaf miner (CLM) Leucoptera coffeella moth is a major threat to coffee production. Insect damage is related to the feeding behavior of the larvae on the leaf. During the immature life stages, the insect feeds in the mesophyll triggering necrosis and causing loss of photosynthetic capacity, defoliation and significant yield loss to coffee crops. Chemical control is used to support the coffee production chain, though market requirements move toward conscious consumption claiming for more sustainable methods. In this overview, we discuss aspects about the CLM concerning biology, history, geographical distribution, economic impacts, and the most relevant control strategies in progress. Insights to develop an integrated approach for a safer and eco-friendly control of the CLM are discussed here, including bio-extracts, nanotechnology, pheromones, and tolerant cultivars.

5.
Macromol Mater Eng ; 306(1)2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34539237

RESUMO

In order to better understand the relationship between Flagelliform (Flag) spider silk molecular structural organization and the mechanisms of fiber assembly, it was designed and produced the Nephilengys cruentata Flag spidroin analogue rNcFlag2222. The recombinant proteins are composed by the elastic repetitive glycine-rich motifs (GPGGX/GGX) and the spacer region, rich in hydrophilic charged amino acids, present at the native silk spidroin. Using different approaches for nanomolecular protein analysis, the structural data of rNcFlag2222 recombinant proteins were compared in its fibrillar and in its fully solvated states. Based on the results was possible to identify the molecular structural dynamics of NcFlag2222 prior to and after fiber formation. Overal rNcFlag2222 shows a mixture of semiflexible and rigid conformations, characterized mostly by the presence of PPII, ß-turn and ß-sheet. These results agree with previous studies and bring insights about the molecular mechanisms that might driven Flag silk fibers assembly and elastomeric behavior.

6.
Plant J ; 107(6): 1681-1696, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34231270

RESUMO

Plant expansins are structural cell wall-loosening proteins implicated in several developmental processes and responses to environmental constraints and pathogen infection. To date, there is limited information about the biological function of expansins-like B (EXLBs), one of the smallest and less-studied subfamilies of plant expansins. In the present study, we conducted a functional analysis of the wild Arachis AdEXLB8 gene in transgenic tobacco (Nicotiana tabacum) plants to clarify its putative role in mediating defense responses to abiotic and biotic stresses. First, its cell wall localization was confirmed in plants expressing an AdEXLB8:eGFP fusion protein, while nanomechanical assays indicated cell wall reorganization and reassembly due to AdEXLB8 overexpression without compromising the phenotype. We further demonstrated that AdEXLB8 increased tolerance not only to isolated abiotic (drought) and biotic (Sclerotinia sclerotiorum and Meloidogyne incognita) stresses but also to their combination. The jasmonate and abscisic acid signaling pathways were clearly favored in transgenic plants, showing an activated antioxidative defense system. In addition to modifications in the biomechanical properties of the cell wall, we propose that AdEXLB8 overexpression interferes with phytohormone dynamics leading to a defense primed state, which culminates in plant defense responses against isolated and combined abiotic and biotic stresses.


Assuntos
Arachis/genética , Nicotiana/fisiologia , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Ácido Abscísico/metabolismo , Animais , Ascomicetos/patogenicidade , Fenômenos Biomecânicos , Parede Celular/genética , Parede Celular/metabolismo , Ciclopentanos/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Células Vegetais/metabolismo , Folhas de Planta/fisiologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Nicotiana/citologia , Nicotiana/genética , Nicotiana/microbiologia , Tylenchoidea/patogenicidade
7.
Front Vet Sci ; 8: 676956, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34179169

RESUMO

The aim of this study was to estimate the energy and protein requirements for maintenance and growth of lambs. A total of 35 crossbreed Dorper × Santa Ines lambs [31 ± 1.28 kg of initial body weight (BW) and 4 months old] were distributed in a completely randomized design with three treatments groups (ad libitum, 30 and 60% of feed restriction). Five lambs were slaughtered at the beginning of the experimental trial as a reference group to estimate the initial empty BW (EBW) and body composition. When the animals of the ad libitum treatment reached a BW average of 47.2 kg, at day 84 of trial, all lambs were slaughtered. The feed restriction promoted reduction in body fat (P < 0.001) and energy concentration (P < 0.001), while protein showed a quadratic response (P = 0.05). The equations obtained for NEg and NPg requirements were 0.2984 × EBW0.75 × EBWG0.8069 and 248.617 × EBW-0.15546, respectively. The net energy (NEm) and protein (NPm) for maintenance were 71.00 kcal/kg EBW0.75/day and 1.76 g/kg EBW0.75/day, respectively. In conclusion, the NEg and NPg requirement for lambs with 30 kg of BW and 200 g of average daily gain (ADG) were 0.736 Mcal/day and 24.38 g/day, respectively. Our findings indicate that the NEm for crossbreed Dorper × Santa Ines lambs is similar to those recommended by the international committees; however, we support the hypothesis that the requirements for gain are lower.

8.
J Nanosci Nanotechnol ; 19(12): 7826-7832, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31196295

RESUMO

Rattlesnakes are easily recognized by a rattle on the tail. Despite the advances in molecular, morphological, and evolutionary studies about several aspects of rattles, there are no studies elucidating these nanoscale topographical features using high-resolution techniques. Here we propose a set of approaches to show these micro/nano surface features searching for patterns or hidden signatures. The results showed that the older rattle ring (segment 8) presented higher roughness values when compared to other segments. Cluster analysis allowed the observation of similarities/differences among some groups, which reinforced the strong discrepancy of the segment 8 when compared to the others and enable possible topographical transitions among each segment features, considering their linkages and Euclidean distances. Attractive forces and surface hardness were also significant increased on segment 8, while adhesion was significantly decreased on the segments 5, 6, and 7 compared to segment 1 (P < 0.05). Fourier transform infrared spectroscopy showed typical profiles of keratin spectra considering the amino acids present in this protein structure. Energy dispersive spectroscopy results indicated possible different molecular composition on each segment. These set of approaches applied on the present study represents an array of new possibilities towards the qualitative and quantitative analyses of this type of biomaterials enabling to address several structural, chemical and mechanical questions ongoing on scientific world.


Assuntos
Crotalus , Nanoestruturas , Animais , Materiais Biocompatíveis , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
9.
Food Res Int ; 122: 123-128, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229063

RESUMO

The aim of the present study concerns the development, characterization and sensory evaluation of a dual-functional whey hydrolysate. Four concentrations of commercial pepsin (0.48%, 0.95%, 1.43%, 1.91% w/w) were evaluated. The hydrolyses curves and the Reversed-Phase High Performance Liquid Chromatography analyses showed a direct relationship between enzyme concentration and degree of hydrolysis. Through mass spectrometry 21 peptides were identified and 5 of them have never been described in the literature before. The hydrolysate produced (PC3) induced a vascular relaxation of 65.02% in phenylephrine-contracted rat aortic rings. PC3 powder presented a homogeneous aspect with a mean particle size of 86.39 µm, high water solubility (>92%) in a wide pH range (1-12) and an increase of 33% in oil absorption capacity, when compared to the unhydrolyzed product. Sensory analysis showed a high acceptance (7.6 in a 9-point hedonic scale) of the hydrolysate among 100 consumers. The results brought the possibility of developing a whey hydrolysate with high vasorelaxant activity, great technological properties and sensory appeal, as an interesting dual-functional ingredient to be incorporated into food products.


Assuntos
Comportamento do Consumidor/estatística & dados numéricos , Hidrolisados de Proteína/química , Proteínas do Soro do Leite/química , Animais , Aorta/efeitos dos fármacos , Bovinos , Cromatografia de Fase Reversa , Manipulação de Alimentos , Humanos , Hidrólise , Espectrometria de Massas , Hidrolisados de Proteína/farmacologia , Ratos , Vasodilatadores/química , Vasodilatadores/farmacologia
10.
J Sci Food Agric ; 99(9): 4248-4259, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30801730

RESUMO

BACKGROUND: Silver nanoparticles (AgNPs), particularly those entrapped in polymeric nanosystems, have arisen as options for managing plant bacterial diseases. Among the biopolymers useful for the entrapment of AgNPs, chitosan is promising because of its low cost, good biocompatibility, antimicrobial properties and biodegradability. The present study aimed: (i) to greenly-synthesize AgNPs using different concentrations of aqueous extract of tomato leaves followed by entrapment of AgNPs with chitosan (CH-AgNPs); (ii) to characterize the optical, structural and biological properties of the nanosystems produced; (iii) to evaluate the antimicrobial activities of AgNPs and nanomaterials; and (iv) to assess the effectiveness of AgNPs and nanomaterials for controlling tomato bacterial wilt caused by Ralstonia solanacearum. RESULTS: Spherical and oval AgNPs had incipient colloidal instability, although the concentration of the tomato leaf extract influenced both size (< 87 nm) and the polydispersity index. Nanomaterials (< 271 nm in size) were characterized by a highly stable matrix of chitosan containing polydisperse AgNPs. Free AgNPs and CH-AgNPs were stable for up to 30 days, with no significant alteration in physicochemical parameters. The AgNPs and nanomaterials had antibacterial activity and decreased bacterial growth at micromolar concentrations after 48 h. Morphological changes in R. solanacearum cells were observed after treatment with CH-AgNPs. The application of CH-AgNPs at 256 µmol L-1 reduced the incidence of bacterial wilt in a partially resistant tomato genotype but not in the susceptible line. CONCLUSION: Greenly-synthesized chitosan-derived nanomaterials containing AgNPs produced with leaf extracts from their own species appear to comprise a promising and sustainable alternative in an integrated management approach aiming to reduce the yield losses caused by bacterial wilt. © 2019 Society of Chemical Industry.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Quitosana/química , Química Verde/métodos , Doenças das Plantas/microbiologia , Extratos Vegetais/química , Prata/farmacologia , Solanum lycopersicum/química , Antibacterianos/química , Portadores de Fármacos/química , Composição de Medicamentos , Solanum lycopersicum/microbiologia , Nanoestruturas/química , Folhas de Planta/química , Ralstonia/efeitos dos fármacos , Ralstonia/crescimento & desenvolvimento , Prata/química
11.
J Proteomics ; 192: 299-310, 2019 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-30267876

RESUMO

Peanut wild relatives (Arachis spp.) have high genetic diversity and are important sources of resistance to biotic and abiotic stresses. In this study, proteins were analyzed in root tissues of A. duranensis submitted to a progressive water deficit in soil and the differential abundance was compared to transcript expression profiles obtained by RNA-seq and qRT-PCR. Using a 2-DE approach, a total of 31 proteins were identified, most of which were associated with stress response and drought perception. These comprised a chitinase-2 (unique to stressed condition), an MLP-like protein, a glycine-rich protein DOT1-like, a maturase K and heat shock-related proteins (HSP70 - an isoform unique to the control, and HSP17.3). Other proteins unique to the control condition comprised a transcription initiation factor IIF subunit alpha-like protein, a SRPBCC ligand-binding domain superfamily protein, an Adenine phosphoribosyl transferase, a Leo1-like protein, a Cobalamine-independent methionine synthase and a Transmembrane emp24 domain-containing protein p24delta9-like. Correlation of mRNA expression and corresponding protein abundance was observed for 15 of the identified proteins, with genes encoding the majority of proteins (14) negatively regulated in stressed roots. Proteins identified in this study offer potential for the genetic improvement of cultivated peanut for drought tolerance. SIGNIFICANCE: The comparison of protein abundance and corresponding transcript expression levels (RNA-seq and qRT-PCR) revealed that 15 of the identified proteins showed similar expression behavior, with the majority (14 proteins) negatively regulated in stressed roots. Chitinase-2 (Cht2) was the only protein with an upregulation behavior in all approaches. These proteins appear to play an important role in drought tolerance in A. duranensis and may be further explored in peanut genetic breeding programs.


Assuntos
Arachis/metabolismo , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/biossíntese , Raízes de Plantas/metabolismo , Arachis/genética , Desidratação/genética , Desidratação/metabolismo , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Raízes de Plantas/genética , Proteômica
12.
J Phys Chem A ; 122(34): 6842-6851, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30074796

RESUMO

The photophysical behavior and reactive oxygen species (ROS) generation by chloroaluminum phthalocyanine (AlClPc) are evaluated by steady state absorption/emission, transient emission, and electron paramagnetic resonance spectroscopies in the presence of graphene oxide (GO), reduced graphene oxide (RGO), and carboxylated nanographene oxide (NGO). AlClPc and graphene oxides form a supramolecular structure stabilized by π-π interactions, which quantitatively quenches fluorescence emission and suppresses ROS generation. These effects occur even when graphenes are previously functionalized with Pluronic F-127. A small part of quenching is due to an inner filter effect, in which graphene oxides compete with AlClPc for light absorption. Nonetheless, most of the (static) quenching arises on the formation of a nonemissive ground state complex between AlClPc and graphene oxides. The efficiency of graphene oxides on the fluorescence quenching and ROS generation suppression follows the order: GO < NGO < RGO.

13.
Peptides ; 106: 37-44, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29933027

RESUMO

A previously undescribed six residues long peptide His-Arg-Phe-Leu-Arg-His was identified and purified from the skin secretion of the amphibian Phyllomedusa centralis. A synthetic analogue carboxyamidated HRFLRH-NH2 showed structural changes induced by CO2 and metal ions in aqueous solution when analyzed by NMR. The present work reports NMR structures for the carboxyamidated hexapeptide in the presence CO2, Zn2+ and Cd2+, suggesting possible affinity regions on the polypeptide chain for each ligand. The NMR structures were optimized by DFT to identify probable biding sites of these species in the polypeptide structure. To our best knowledge, this is the first time that a putative CO2 binding site is described on a peptide structure obtained in aqueous conditions, at room temperature.


Assuntos
Proteínas de Anfíbios/química , Anuros/fisiologia , Dióxido de Carbono/química , Cátions Bivalentes/química , Oligopeptídeos/química , Pele/metabolismo , Proteínas de Anfíbios/isolamento & purificação , Animais , Sítios de Ligação , Cádmio/química , Ligantes , Oligopeptídeos/isolamento & purificação , Conformação Proteica , Zinco/química
14.
Artigo em Inglês | MEDLINE | ID: mdl-28540041

RESUMO

BACKGROUND: An experiment was conducted to evaluate the effects of feed restriction (FR) and sex on the quantitative and qualitative carcass traits of Morada Nova lambs. Thirty-five animals with an initial body weight of 14.5 ± 0.89 kg and age of 120 d were used in a completely randomized study with a 3 × 3 factorial scheme consisting of three sexes (11 entire males, 12 castrated males and 12 females) and three levels of feeding (ad libitum - AL and 30% and 60% FR). RESULTS: Entire males presented greater hot and cold carcass weights (P < 0.05), followed by castrated males and females. However, the hot carcass yield was higher for females and castrated males than for entire males. Luminosity values were influenced (P < 0.05) by sex, with entire males presenting higher values than castrated males and females. Females showed higher (P < 0.05) concentrations of linoleic acid and arachidonic acid in the meat of the longissimus thoracis muscle. The meat of animals submitted to AL intake and 30% FR showed similar (P > 0.05) concentrations, and the concentrations of palmitic acid, palmitoleic acid, stearic acid, oleic acid and conjugated linoleic acid were higher (P < 0.05) than those of animals with 60% FR. The meat of females had a higher ω6/ω3 ratio and lower h/H ratio, and females had greater levels of feeding. The meat of animals on the 60% FR diet had a greater ω6/ω3 ratio, lower h/H ratio and lower concentration of desirable fatty acids in addition to a greater atherogenicity index (AI) and thrombogenicity index (TI). CONCLUSION: Lambs of different sexes had carcasses with different quantitative traits without total influence on the chemical and physical meat characteristics. The lipid profile of the meat was less favorable to consumer health when the animals were female or submitted to 60% feed restriction.

15.
Int J Antimicrob Agents ; 49(2): 167-175, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28108242

RESUMO

Mastoparans, a class of peptides found in wasp venom, have significant effects following a sting as well as useful applications in clinical practice. Among these is their potential use in the control of micro-organisms that cause infectious diseases with a significant impact on society. Thus, the present study describes the isolation and identification of a mastoparan peptide from the venom of the social wasp Pseudopolybia vespiceps and evaluated its antimicrobial profile against bacteria (Staphylococcus aureus and Mycobacterium abscessus subsp. massiliense), fungi (Candida albicans and Cryptococcus neoformans) and in vivo S. aureus infection. The membrane pore-forming ability was also assessed. The mastoparan reduced in vitro and ex vivo mycobacterial growth by 80% at 12.5 µM in infected peritoneal macrophages but did not affect the shape of bacterial cells at the dose tested (6.25 µM). The peptide also showed potent action against S. aureus in vitro (EC50 and EC90 values of 1.83 µM and 2.90 µM, respectively) and reduced the in vivo bacterial load after 6 days of topical treatment (5 mg/kg). Antifungal activity was significant, with EC50 and EC90 values of 12.9 µM and 15.3 µM, respectively, for C. albicans, and 11 µM and 22.70 µM, respectively, for C. neoformans. Peptides are currently attracting interest for their potential in the design of antimicrobial drugs, particularly due to the difficulty of micro-organisms in developing resistance to them. In this respect, Polybia-MPII proved to be highly effective, with a lower haemolysis rate compared with peptides of the same family.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Peptídeos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Venenos de Vespas/farmacologia , Vespas/química , Administração Tópica , Animais , Anti-Infecciosos/isolamento & purificação , Modelos Animais de Doenças , Feminino , Voluntários Saudáveis , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Macrófagos Peritoneais/microbiologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Peptídeos/isolamento & purificação , Resultado do Tratamento , Venenos de Vespas/isolamento & purificação
16.
J Hazard Mater ; 324(Pt B): 634-644, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27889181

RESUMO

Discarded PE-based products pose a social and environmental threat because of their recalcitrance to degradation, a consequence of the unique set of PE's physicochemical properties. In this study we isolated nine novel PE-degrading bacteria from plastic debris found in soil of the savanna-like Brazilian Cerrado. These bacterial strains from the genera Comamonas, Delftia, and Stenotrophomonas showed metabolic activity and cellular viability after a 90-day incubation with PE as the sole carbon source. ATR/FTIR indicated that biodegraded PE undergone oxidation, vinylene formation, chain scission, among other chemical changes. Considerable nanoroughness shifts and vast damages to the micrometric surface were confirmed by AFM and SEM. Further, phase imaging revealed a 46.7% decrease in the viscous area of biodegraded PE whereas Raman spectroscopy confirmed a loss in its crystalline content, suggesting the assimilation of smaller fragments. Intriguingly, biodegraded PE chemical fingerprint suggests that these strains use novel biochemical strategies in the biodegradation process. Our results indicate that these microbes are capable of degrading unpretreated PE of very high molecular weight (191,000gmol-1) and survive for long periods under this condition, suggesting not only practical applications in waste management and environmental decontamination, but also future directions to understand the unraveled metabolism of synthetic polymers.


Assuntos
Comamonas/metabolismo , Delftia/metabolismo , Polietileno/análise , Poluentes do Solo/análise , Stenotrophomonas/metabolismo , Aderência Bacteriana , Brasil , Comamonas/isolamento & purificação , Delftia/isolamento & purificação , Viabilidade Microbiana , Óleo Mineral/análise , Óleo Mineral/metabolismo , Modelos Teóricos , Polietileno/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Stenotrophomonas/isolamento & purificação
17.
Front Immunol ; 8: 1890, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29375557

RESUMO

Although antibiotic-induced dysbiosis has been demonstrated to exacerbate intestinal inflammation, it has been suggested that antibiotic prophylaxis may be beneficial in certain clinical conditions such as acute pancreatitis (AP). However, whether broad-spectrum antibiotics, such as meropenem, influence the dissemination of multidrug-resistant (MDR) bacteria during severe AP has not been addressed. In the currently study, a mouse model of obstructive severe AP was employed to investigate the effects of pretreatment with meropenem on bacteria spreading and disease outcome. As expected, animals subjected to biliopancreatic duct obstruction developed severe AP. Surprisingly, pretreatment with meropenem accelerated the mortality of AP mice (survival median of 2 days) when compared to saline-pretreated AP mice (survival median of 7 days). Early mortality was associated with the translocation of MDR strains, mainly Enterococcus gallinarum into the blood stream. Induction of AP in mice with guts that were enriched with E. gallinarum recapitulated the increased mortality rate observed in the meropenem-pretreated AP mice. Furthermore, naïve mice challenged with a mouse or a clinical strain of E. gallinarum succumbed to infection through a mechanism involving toll-like receptor-2. These results confirm that broad-spectrum antibiotics may lead to indirect detrimental effects during inflammatory disease and reveal an intestinal pathobiont that is associated with the meropenem pretreatment during obstructive AP in mice.

18.
Int. J. Antimicrob. Agents ; 49(2): 167-175, 2017.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15472

RESUMO

Mastoparans, a class of peptides found in wasp venom, have significant effects following a sting as well as useful applications in clinical practice. Among these is their potential use in the control of microorganisms that cause infectious diseases with a significant impact on society. Thus, the present study describes the isolation and identification of a mastoparan peptide from the venom of the social wasp Pseudopolybia vespiceps and evaluated its antimicrobial profile against bacteria (Staphylococcus aureus and Mycobacterium abscessus subsp. massiliense), fungi (Candida albicans and Cryptococcus neoformans) and in vivo S. aureus infection. The membrane pore-forming ability was also assessed. The mastoparan reduced in vitro and ex vivo mycobacterial growth by 80% at 12.5 mu M in infected peritoneal macrophages but did not affect the shape of bacterial cells at the dose tested (6.25 mu M). The peptide also showed potent action against S. aureus in vitro (EC50 and EC90 values of 1.83 mu M and 2.90 mu M, respectively) and reduced the in vivo bacterial load after 6 days of topical treatment (5 mg/kg). Antifungal activity was significant, with EC50 and EC90 values of 12.9 mu M and 15.3 mu M, respectively, for C. albicans, and 11 mu M and 22.70 mu M, respectively, for C. neoformans. Peptides are currently attracting interest for their potential in the design of antimicrobial drugs, particularly due to the difficulty of micro-organisms in developing resistance to them. In this respect, Polybia-MPII proved to be highly effective, with a lower haemolysis rate compared with peptides of the same family.

19.
J Food Sci ; 81(9): C2143-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27472154

RESUMO

This study evaluates the effect of cashew nut meal (CNM), whole cottonseed (WCS), and calcium salts of long-chain fatty acids (Ca-LCFA) on the fatty acid profiles of meat from hair lambs. Thirty-five 60-d-old, male, noncastrated Santa Ines lambs with an initial average body weight of 13.00 ± 1.80 kg were used in a randomized complete-block design with 7 blocks and 5 treatments. The experimental treatments consisted of a control diet (CON) without supplemental lipids and 4 test diets with different lipid supplements that were selected according to the degree of protection from ruminal hydrogenation and their polyunsaturated fatty acid richness. The tests diets included the following modifications: supplementation with WCS, supplementation with CNM, supplementation with both cottonseed and CNM (CSCNM), and supplementation with Ca-LCFA. The C18:1n9c content was highest in the meat of the animals fed the CNM diet (42.00%). The meat from lambs fed the WCS and Ca-LCFA diets had higher C18:0 contents (25.23 and 22.80%, respectively). The C16:1 content was higher in the meat from the animals fed the CNM and CON diets (1.54 and 1.49%, respectively). C18:2c9t11 concentration was higher in the meat from the animals fed the Ca-LCFA and CNM diets. The estimated enzyme activity of Δ9-desaturase C18 was highest in the muscles of the lambs fed the CON, CNM, and CSCNM diets. The use of cashew nuts in the diet resulted in an increase in the C18:2c9t11 content of the lamb meat, which improved the nutritional characteristics of the fat.


Assuntos
Anacardium/química , Óleo de Sementes de Algodão/química , Ácidos Graxos Insaturados/análise , Nozes/química , Carne Vermelha/análise , Ração Animal/análise , Animais , Peso Corporal , Dieta/veterinária , Análise de Alimentos , Masculino , Músculo Esquelético/química , Ovinos
20.
Front Microbiol ; 6: 616, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26150808

RESUMO

The dimorphic fungi Paracoccidioides spp. are the etiological agents of paracoccidioidomycosis (PCM), a mycosis of high incidence in Brazil. The toxicity of drug treatment and the emergence of resistant organisms have led to research for new candidates for drugs. In this study, we demonstrate that the natural product argentilactone was not cytotoxic or genotoxic to MRC5 cells at the IC50 concentration to the fungus. We also verified the proteomic profile of Paracoccidioides lutzii after incubation with argentilactone using a label free quantitative proteome nanoUPLC-MS(E). The results of this study indicated that the fungus has a global metabolic adaptation in the presence of argentilactone. Enzymes of important pathways, such as glycolysis, the Krebs cycle and the glyoxylate cycle, were repressed, which drove the metabolism to the methylcytrate cycle and beta-oxidation. Proteins involved in cell rescue, defense and stress response were induced. In this study, alternative metabolic pathways adopted by the fungi were elucidated, helping to elucidate the course of action of the compound studied.

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