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1.
Toxicon ; 217: 41-45, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940358

RESUMO

The mixed quality evidence about non-front-fanged snake bites has included unsupported speculation and presumption; the possible role of atopy and/or primary hypersensitivity have often been prematurely discounted. Described is a medically insignificant bite by a captive African emerald snake, Hapsidophrys smaragdinus Schlegel, 1837 (Colubridae, Colubrinae) that caused the development of moderate Type IV hypersensitivity; the 44-year-old male victim experienced persistent pruritis and an erythematous bite site maculopapular dermatitis that slowly resolved and required 6 days for full resolution. The victim had received several previous medically insignificant bites from non-front-fanged snakes. Brief comparison is made with a previously reported case consistent with a mixed clinical picture of local mild envenoming and hypersensitivity from a bite by another colubrine, the coin snake (Hemmorhois nummifer). This case highlights slowly accumulating evidence supporting the risk of acquired and primary hypersensitivity to some snakebites in susceptible individuals. In order to provide accurate medical risk profiles for less-known snake species it is essential that the case of any patient developing acute or delayed effects from bites by these species is formally documented. The need for further attention to atopic risks, especially in private collectors, is emphasised with consideration of venom/other ophidian product-induced anaphylaxis.


Assuntos
Colubridae , Dermatite Atópica , Mordeduras de Serpentes , Adulto , Animais , Documentação , Humanos , Masculino , Mordeduras de Serpentes/veterinária , Venenos de Serpentes
2.
NPJ Biofilms Microbiomes ; 8(1): 58, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35835775

RESUMO

Here we report two antimicrobial peptides (AMPs), HG2 and HG4 identified from a rumen microbiome metagenomic dataset, with activity against multidrug-resistant (MDR) bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA) strains, a major hospital and community-acquired pathogen. We employed the classifier model design to analyse, visualise, and interpret AMP activities. This approach allowed in silico discrimination of promising lead AMP candidates for experimental evaluation. The lead AMPs, HG2 and HG4, are fast-acting and show anti-biofilm and anti-inflammatory activities in vitro and demonstrated little toxicity to human primary cell lines. The peptides were effective in vivo within a Galleria mellonella model of MRSA USA300 infection. In terms of mechanism of action, HG2 and HG4 appear to interact with the cytoplasmic membrane of target cells and may inhibit other cellular processes, whilst preferentially binding to bacterial lipids over human cell lipids. Therefore, these AMPs may offer additional therapeutic templates for MDR bacterial infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/farmacologia , Lipídeos/farmacologia , Lipídeos/uso terapêutico , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/metabolismo
4.
Data Brief ; 40: 107728, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34977304

RESUMO

This report presents survey data about the socioeconomic conditions and governance of informal workers in Cali, Colombia during the COVID-19 pandemic. Conducted with 750 street vendors via telephone, the survey explores eight interrelated topics: demographics, households and children, economic activities, income and expenses, access to financial services and debt, institutional trust, health, and subjective wellbeing. These data are valuable for two reasons. First, they allow for an analysis of the social and economic consequences of the pandemic for a population group that remains understudied and neglected by social policy. Second, they allow for an understanding of the governance of informal work during crises and possible paths to promote greater inclusion. Taken together, the data presented here provide tools for conducting academic and policy-relevant analysis about informal workers, the long-term consequences of COVID-19 in the global South, and how recovery from the pandemic can be made more inclusive and sustainable.

5.
Data Brief ; 37: 107268, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34401414

RESUMO

This analysis presents data collected through an online survey about the quality of life, health, subjective wellbeing, and government perception in four cities in Colombia during the COVID-19 crisis. Four universities and a local newspaper promoted the survey to assess how the pandemic affected the population's quality of life in a broad range of social and economic aspects. Respondents were adults (+18 years old) living in the largest Colombia cities: Bogotá, Medellín, Cali, and Barranquilla, totaling 1637 complete observations. Researchers used snowballing sampling strategy, social networks, a web page, and an advertisement in the partner newspaper for data collection. This data set helps to conduct social research and policy reports about the consequences of the pandemic. The data enclosed in this paper includes socioeconomic variables, income reduction, employment, household composition, teleworking, indebtedness, physical and mental health, physical activity behavior, subjective wellbeing, affective and communal relationships, institutional trust, and perception of government performance during COVID-19. We aim at contributing to a better understating of the consequences of the pandemic in Colombia and general in the Global South through the collection and dissemination of data for academic and policy purposes.

6.
Toxicon ; 200: 92-95, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34280410

RESUMO

The first reported snakebite by an African snake-eater, Polemon spp. (Atractaspididae, Aparallactinae); Local envenoming by Reinhardt's snake-eater, Polemon acanthias (Reinhardt, 1860). Toxicon XX, xxx. A 51-yr-old male herpetologist was bitten on the left index finger by a captive male Polemon acanthias while manually removing fragments of incompletely shed skin from the specimen. The snake sustained its bite for approximately 2 mins, advancing its jaws several times. The victim rapidly developed moderate pain, erythema, progressive edema that ultimately extended to the left wrist; a blister later developed in the wound site, as well as joint stiffness in the bitten and adjacent two fingers that limited flexion and extension. These effects regressed during the week following the bite, but recurred thereafter and were similar to the effects that developed immediately post-envenoming. There were no systemic signs or symptoms. The victim sought medical advice and was treated with broad-spectrum antibiotics, antihistamines and wound care; no laboratory investigations were conducted. He improved during the subsequent month with complete resolution in 5 and one-half weeks. This is the first documented bite by a Polemon spp. and the victim's clinical course suggests the development of local effects from venom components. The phylogenetic relationship of Polemon spp. with the burrowing asps (Atractaspis spp.) and the similarity of some of the features of this local envenoming by P. acanthias with mild/moderate envenoming by some Atractaspis spp., suggests that none of these snakes should be handled; they should be considered capable of inflicting potentially serious envenoming.


Assuntos
Mordeduras de Serpentes , Animais , Antivenenos/uso terapêutico , Venenos Elapídicos , Elapidae , Masculino , Filogenia , Mordeduras de Serpentes/tratamento farmacológico
7.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806791

RESUMO

The world is on the verge of a major antibiotic crisis as the emergence of resistant bacteria is increasing, and very few novel molecules have been discovered since the 1960s. In this context, scientists have been exploring alternatives to conventional antibiotics, such as ribosomally synthesized and post-translationally modified peptides (RiPPs). Interestingly, the highly potent in vitro antibacterial activity and safety of ruminococcin C1, a recently discovered RiPP belonging to the sactipeptide subclass, has been demonstrated. The present results show that ruminococcin C1 is efficient at curing infection and at protecting challenged mice from Clostridium perfringens with a lower dose than the conventional antibiotic vancomycin. Moreover, antimicrobial peptide (AMP) is also effective against this pathogen in the complex microbial community of the gut environment, with a selective impact on a few bacterial genera, while maintaining a global homeostasis of the microbiome. In addition, ruminococcin C1 exhibits other biological activities that could be beneficial for human health, as well as other fields of applications. Overall, this study, by using an in vivo infection approach, confirms the antimicrobial clinical potential and highlights the multiple functional properties of ruminococcin C1, thus extending its therapeutic interest.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Peptídeos/farmacologia , Antibacterianos/química , Antifúngicos/farmacologia , Bacteriocinas/química , Biofilmes/efeitos dos fármacos , Clostridiales/metabolismo , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/microbiologia , Clostridium perfringens/efeitos dos fármacos , Humanos , Peptídeos/química , Processamento de Proteína Pós-Traducional
8.
Pacing Clin Electrophysiol ; 44(5): 843-855, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33742449

RESUMO

BACKGROUND: Predictors of high-degree atrioventricular block (HAVB) after transcatheter aortic valve replacement (TAVR) are recognized, but the electrophysiological study's (EPS) role is still a subject to debate. The objective of our study was to determine factors associated with PPM implantation including the potential role of EPS before and/or after TAVR. METHODS AND RESULTS: Seventy four consecutive patients (pts) were included and 21 pts (28.4%) received a PPM during the immediate postoperative follow-ups (until Day 5): HAVB in 15 pts (71.4%), prophylactic implantation due to a documented increased HV interval ≥ 95-100 ms plus LBBB in 2 pts (9.5%), a high-degree HV block evidenced at the EPS plus LBBB in 3 pts (14.3%) and one additional patient was implanted for AV-block in presence of AFib (4.8%). In the multivariate model 1 including parameters before TAVR, both prosthesis diameter and PR lengthening remained significantly associated with PPM as well RBBB. In the multivariate model 2 including parameters after TAVR, only HV remained significantly associated with the risk of PPM (OR = 1.15 (1.05-1.26), p = .004). When all the significant variables in models 1 and 2 were analyzed together in model 3, only HV after TAVR remained significantly associated with an increased risk of PPM. CONCLUSIONS: In this prospective observational study, it was revealed that a Day 4-5 EPS is likely to more precisely stratify the risk of PPM implantation regarding its ability to discover asymptomatic severe infra-hisian conduction disturbances particularly in presence of LBBB. Multivariate analysis confirmed the prognostic value of HV alteration.


Assuntos
Bloqueio Atrioventricular/etiologia , Doença do Sistema de Condução Cardíaco/etiologia , Técnicas Eletrofisiológicas Cardíacas , Marca-Passo Artificial , Complicações Pós-Operatórias/etiologia , Substituição da Valva Aórtica Transcateter , Idoso de 80 Anos ou mais , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Doença do Sistema de Condução Cardíaco/fisiopatologia , Doença do Sistema de Condução Cardíaco/terapia , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/terapia , Prognóstico , Estudos Prospectivos , Medição de Risco
9.
Food Chem ; 350: 129222, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33607411

RESUMO

The reaction pathways were investigated by which a fungoid chitosan (CsG) may protect against photooxidative decay of model solutions and a sulphite-free white wine. Samples containing CsG were dark incubated for 2 days before exposure to fluorescent lighting for up to 21 days in the presence of wine like (+)-catechin and/or iron doses. In both systems CsG at winemaking doses significantly reduced the photoproduction of acetaldehyde and, to a better extent, glyoxylic acid, two key reactive aldehydes implicated in wine oxidative spoilage. After 21 days, CsG was two-fold more effective than sulphur dioxide in preventing glyoxylic acid formation and minimizing the browning of white wine. Among the antioxidant mechanisms involved in CsG protective effect, iron chelation, and hydrogen peroxide quenching were demonstrated. Besides, the previously unreported tartrate displacement from the [iron(III)-tartrate] complex was revealed as an additional inhibitory mechanism of CsG under photo-Fenton oxidation conditions.


Assuntos
Aldeídos/química , Quitosana/química , Processos Fotoquímicos , Vinho/análise , Antioxidantes/química , Catequina/química , Glioxilatos/química , Oxirredução , Dióxido de Enxofre/química , Tartaratos/química
10.
Front Microbiol ; 11: 579521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281771

RESUMO

Plant α-galactosides belonging to the raffinose family oligosaccharides (RFOs) and considered as prebiotics, are commonly degraded by α-galactosidases produced by the human gut microbiome. In this environment, the Ruminococcus gnavus E1 symbiont-well-known for various benefit-is able to produce an original RgAgaSK bifunctional enzyme. This enzyme contains an hydrolytic α-galactosidase domain linked to an ATP dependent extra-domain, specifically involved in the α-galactoside hydrolysis and the phosphorylation of the glucose, respectively. However, the multi-modular relationships between both catalytic domains remained hitherto unexplored and has been, consequently, herein investigated. Biochemical characterization of heterologously expressed enzymes either in full-form or in separated domains revealed similar kinetic parameters. These results were supported by molecular modeling studies performed on the whole enzyme in complex with different RFOs. Further enzymatic analysis associated with kinetic degradation of various substrates followed by high pressure anionic exchange chromatography revealed that catalytic efficiency decreased as the number of D-galactosyl moieties branched onto the oligosaccharide increased, suggesting a preference of RgAgaSK for RFO's short chains. A wide prevalence and abundance study on a human metagenomic library showed a high prevalence of the RgAgaSK encoding gene whatever the health status of the individuals. Finally, phylogeny and synteny studies suggested a limited spread by horizontal transfer of the clusters' containing RgAgaSK to only few species of Firmicutes, highlighting the importance of these undispersed tandem activities in the human gut microbiome.

11.
Proc Natl Acad Sci U S A ; 117(32): 19168-19177, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32719135

RESUMO

The emergence of superbugs developing resistance to antibiotics and the resurgence of microbial infections have led scientists to start an antimicrobial arms race. In this context, we have previously identified an active RiPP, the Ruminococcin C1, naturally produced by Ruminococcus gnavus E1, a symbiont of the healthy human intestinal microbiota. This RiPP, subclassified as a sactipeptide, requires the host digestive system to become active against pathogenic Clostridia and multidrug-resistant strains. Here we report its unique compact structure on the basis of four intramolecular thioether bridges with reversed stereochemistry introduced posttranslationally by a specific radical-SAM sactisynthase. This structure confers to the Ruminococcin C1 important clinical properties including stability to digestive conditions and physicochemical treatments, a higher affinity for bacteria than simulated intestinal epithelium, a valuable activity at therapeutic doses on a range of clinical pathogens, mediated by energy resources disruption, and finally safety for human gut tissues.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Clostridiales/química , Peptídeos/química , Peptídeos/farmacologia , Antibacterianos/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Peptídeos/isolamento & purificação
12.
Cancer Chemother Pharmacol ; 85(2): 425-432, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31974652

RESUMO

Activated cap-dependent translation promotes cancer by stimulating translation of mRNAs encoding malignancy-promoting proteins. The nucleoside monophosphate Protide, 4Ei-10, undergoes intracellular uptake and conversion by Hint1 to form 7-Cl-Ph-Ethyl-GMP. 7-Cl-Ph-Ethyl-GMP is an analog of cap and inhibits protein translation by binding and sequestering eIF4E thus blocking eIF4E from binding to the mRNA cap. The effects of inhibiting translation initiation by disruption of the eIF4F complex with 4Ei-10 were examined in malignant mesothelioma (MM). In a cell-free assay system, formation of the eIF4F complex was disabled in response to exposure to 4Ei-10. Treatment of MM with 4Ei-10 resulted in decreased cell proliferation, increased sensitivity to pemetrexed and altered expression of malignancy-related proteins. In light of these findings, suppression of translation initiation by small molecule inhibitors like 4Ei-10 alone or in combination with pemetrexed represents an encouraging strategy meriting further evaluation in the treatment of MM.


Assuntos
Antineoplásicos/farmacologia , Carcinogênese/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mesotelioma/tratamento farmacológico , Mesotelioma/genética , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Fator de Iniciação 4F em Eucariotos/genética , Humanos , Mesotelioma Maligno , Pemetrexede/farmacologia , RNA Mensageiro/genética , Bibliotecas de Moléculas Pequenas/farmacologia
13.
Toxicon ; 173: 1-4, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31726079

RESUMO

Snakebite envenoming is a relevant public health problem in French Guiana, and Bothrops atrox is responsible for the vast majority of envenomings in this overseas French territory. The preclinical efficacy of freeze-dried antivenoms manufactured in Costa Rica (Polival-ICP®) and Mexico (Antivipmyn Tri®) was assessed against the lethal, hemorrhagic, in vitro coagulant, and myotoxic effects of Bothrops atrox venom from French Guiana. Antivenoms differ in protein concentration and in the type of active principle (IgG and F (ab')2, respectively). Polival-ICP® showed significantly higher neutralizing activity against lethal, hemorrhagic and in vitro coagulant activities of the venom. Antivenoms neutralized myotoxic effect to a similar extent. In the case of lethal activity, Antivipmyn Tri® did not neutralize the effect at the highest antivenom level tested (1 mg venom/mL antivenom).


Assuntos
Antivenenos/farmacologia , Bothrops , Mordeduras de Serpentes , Animais , Antivenenos/uso terapêutico , Costa Rica , Guiana Francesa , Hemorragia , México
14.
Eur J Med Chem ; 183: 111708, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31550659

RESUMO

A series of substituted di-indolglyoxylamido-spermine analogues were prepared and evaluated for intrinsic antimicrobial properties and the ability to enhance antibiotic action. As a compound class, intrinsic activity was typically observed towards Gram-positive bacteria and the fungus Cryptococcus neoformans, with notable exceptions being the 5-bromo- and 6-chloro-indole analogues which also exhibited modest activity (MIC 34-50 µM) towards the Gram-negative bacteria Escherichia coli and Klebsiella pneumoniae. Several analogues enhanced the activity of doxycycline towards the Gram-negative bacteria Pseudomonas aeruginosa, E. coli, K. pneumoniae and Acinetobacter baumannii. Of particular note was the identification of five antibiotic enhancing analogues (5-Br, 7-F, 5-Me, 7-Me, 7-OMe) which also exhibited low to no cytotoxicity and red blood cell haemolytic properties. The mechanisms of action of the 5-Br and 7-F analogues were attributed to the ability to disrupt the integrity of, and depolarize, bacterial membranes.


Assuntos
Antibacterianos/química , Indóis/química , Espermina/análogos & derivados , Espermina/química , Antibacterianos/farmacologia , Linhagem Celular , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Cefalosporinas/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Hemólise , Humanos , Hidrólise , Indóis/farmacologia , Testes de Sensibilidade Microbiana , Transdução de Sinais , Espermina/farmacologia
15.
Bioorg Med Chem ; 27(10): 2090-2099, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30975502

RESUMO

The combination of increased incidence of drug-resistant strains of bacteria and a lack of novel drugs in development creates an urgency for the search for new antimicrobials. Initial screening of compounds from an in-house library identified two 6-bromoindolglyoxylamide polyamine derivatives (3 and 4) that exhibited intrinsic antimicrobial activity towards Gram-positive bacteria, Staphylococcus aureus and S. intermedius with polyamine 3 also displaying in vitro antibiotic enhancing properties against the resistant Gram-negative bacterium Pseudomonas aeruginosa. A series of 6-bromo derivatives (5-15) were prepared and biologically evaluated, identifying analogues with enhanced antibacterial activity towards Escherichia coli and with moderate to excellent antifungal properties. Polyamine 3, which includes a spermine chain, was the most potent of the series - its mechanism of action was attributed to rapid membrane permeabilization and depolarization in both Gram-positive and Gram-negative bacteria.


Assuntos
Antibacterianos/química , Anti-Infecciosos/química , Poliaminas/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Linhagem Celular , Sobrevivência Celular , Farmacorresistência Bacteriana/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Indóis/química , Testes de Sensibilidade Microbiana , Poliaminas/farmacologia
16.
J Evol Biol ; 31(12): 1782-1793, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30193402

RESUMO

The phylogenetic relationships between the three main clades of worm snakes remain controversial. This question is, however, crucial to elucidate the origin of the successful snake radiation, as these burrowing and miniaturized wormlike organisms represent the earliest branching clades within the snake tree. The present molecular phylogenetic study, intended to minimize the amount of missing data, provides fully resolved inter-subfamilial relationships among Typhlopidae. It also brings robust evidence that worm snakes (Scolecophidia) are paraphyletic, with the scolecophidian family Anomalepididae recovered with strong support as sister clade to the 'typical snakes' (Alethinophidia). Ancestral state reconstructions applied to three different traits strongly associated to a burrowing life-style (scolecoidy, absence of retinal cones and microstomy) provide results in favour of a burrowing origin of snakes, and suggest that worm snakes might be the only extant fossorial representatives of the primordial snake incursion towards an underground environment.


Assuntos
Evolução Biológica , Especiação Genética , Serpentes/genética , Animais , Filogenia , Serpentes/classificação , Fatores de Tempo
17.
Ecotoxicology ; 27(10): 1331-1340, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30244326

RESUMO

Aquatic organisms are exposed to a myriad of chemical compounds, with particular concerns focused on endocrine disruptors. Growing scientific evidence indicates that these compounds interfere with normal endocrine function and could affect the reproductive system of humans and wildlife. We analyzed the proportion of masculinized females, defined by elongation and fusion of the anal fin rays, and the extent of masculinization, masculinization index, defined by anal fin length divided by the standard length, of Cnesterodon decemmaculatus resident to areas of agricultural and urban-industrial activities in the Arroyo Colorado basin. Additionally, a bioassay was carried out to assess the potential effects of masculinization on reproductive success, measured as the number of viable progenies, using pregnant females from the site downstream of the urban-industrial zone. Masculinized females were observed in all sampling sites, particularly downstream of the urban-industrial area, where over 80% of females presented abnormal sexual characteristics and the highest masculinization index was registered. In the laboratory, masculinized adult females showed male mating behavior, and survival of their progeny was lower than those of normal females. To our knowledge, this is the first report of endocrine disruption in field-collected C. decemmaculatus, and the first evaluation of the reproductive success of masculinized females. Finally, our results support C. decemmaculatus as an excellent sentinel species due to its wide distribution, easy culture in laboratory conditions, and its potential capability to respond to sources of pollution, particularly endocrine disruptors.


Assuntos
Ciprinodontiformes/fisiologia , Disruptores Endócrinos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Feminino
18.
ChemMedChem ; 13(10): 1018-1027, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29465814

RESUMO

The emergence of multidrug-resistant bacteria and pathogens has created an urgent need for the development of new antibiotics. Herein we report our investigations into the broad-spectrum activity of an easily prepared water-soluble polyaminosterol compound, namely claramine A1, against both drug-sensitive and drug-resistant Gram-negative and Gram-positive bacterial strains. We also report its peculiar mechanism of action, which differs from that of all the other well-known classes of antibiotics, toward Gram-negative and Gram-positive bacteria. Given their low cytotoxicity, this class of compounds based on claramine A1 could constitute an effective response to combat the emergence of multidrug-resistant bacteria and nosocomial diseases.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Colestanos/química , Colestanos/farmacologia , Espermina/análogos & derivados , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Larva/efeitos dos fármacos , Testes para Micronúcleos , Estrutura Molecular , Mariposas/efeitos dos fármacos , Espermina/química , Espermina/farmacologia , Relação Estrutura-Atividade
19.
Sci Rep ; 7(1): 5880, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28724959

RESUMO

The metabolic effects of an oral supplementation with a Curcuma longa extract, at a dose nutritionally relevant with common human use, on hepatic metabolism in rats fed a high fructose and saturated fatty acid (HFS) diet was evaluated. High-resolution magic-angle spinning NMR and GC/MS in combination with multivariate analysis have been employed to characterize the NMR metabolite profiles and fatty acid composition of liver tissue respectively. The results showed a clear discrimination between HFS groups and controls involving metabolites such as glucose, glycogen, amino acids, acetate, choline, lysophosphatidylcholine, phosphatidylethanolamine, and ß-hydroxybutyrate as well as an increase of MUFAs and a decrease of n-6 and n-3 PUFAs. Although the administration of CL did not counteract deleterious effects of the HFS diet, some metabolites, namely some n-6 PUFA and n-3 PUFA, and betaine were found to increase significantly in liver samples from rats having received extract of curcuma compared to those fed the HFS diet alone. This result suggests that curcuminoids may affect the transmethylation pathway and/or osmotic regulation. CL extract supplementation in rats appears to increase some of the natural defences preventing the development of fatty liver by acting on the choline metabolism to increase fat export from the liver.


Assuntos
Suplementos Nutricionais , Fígado/metabolismo , Extratos Vegetais/farmacologia , Animais , Betaína/metabolismo , Colina/metabolismo , Curcuma , Dieta Hiperlipídica , Análise Discriminante , Ácidos Graxos , Frutose , Glutationa/metabolismo , Análise dos Mínimos Quadrados , Masculino , Malondialdeído/metabolismo , Análise Multivariada , Espectroscopia de Prótons por Ressonância Magnética , Ratos Sprague-Dawley , Triglicerídeos/metabolismo
20.
Talanta ; 170: 119-127, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28501147

RESUMO

Myeloperoxidase (MPO) is a key enzyme derived from leukocytes which is associated with the initiation and progression of many inflammatory diseases. Increased levels of MPO may contribute to cellular dysfunction and tissues injury by producing highly reactive oxidants such as hypochlorous acid (HOCl). Myeloperoxidase-generated HOCl is therefore considered as a relevant biomarker of oxidative stress-related damage and its quantitation is of great importance to the study of disease progression. In this context, the current study describes a rapid, sensitive and homogeneous fluorescence-based method for detecting the MPO chlorination activity in biological samples. This assay utilizes 7-hydroxy-2-oxo-2H-chromene-8-carbaldehyde oxime as a selective probe for HOCl detection, and is adapted to 96-well microplates to allow high-throughput quantitation of active MPO. The ability of the method to monitor HOCl release was further investigated in hyperglycemic streptozotocin-treated diabetic rats. The data proved that the present assay has a reliable performance when quantitating the active MPO in the plasma of diabetic animals, a feature of inflammatory disease found concomitant with an elevation of protein carbonyls levels and lipid peroxidation and which was negatively correlated with the ratio of reduced-to-oxidized glutathione.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Ensaios Enzimáticos/métodos , Ácido Hipocloroso/metabolismo , Estresse Oxidativo , Peroxidase/metabolismo , Animais , Células HL-60 , Halogenação , Humanos , Masculino , Peroxidase/sangue , Ratos , Espectrometria de Fluorescência
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