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1.
Braz J Med Biol Res ; 56: e12404, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37042868

RESUMO

Secondary metabolites produced by endophytes are an excellent source of biologically active compounds. The newly isolated natural products terezine E and 14-hydroxyterezine D are endophytic metabolites exhibiting anticancer activity recently identified by our team (https://doi.org/10.1080/14786419.2018.1489393). In our current study, we evaluated their affinity for binding to the active site of histone deacetylase (PDB ID: 4CBT) and matrix metalloproteinase 9 (PDB ID: 4H3X) by molecular docking using AutoDock Vina software after having tested their cytotoxic activities on three cell lines (human ductal breast epithelial tumor cells (T47D)-HCC1937), human hepatocarcinoma cell line (HepG2)-HB8065), and human colorectal carcinoma cells (HCT-116)-TCP1006, purchased from ATCC, USA)). Additionally, their antimicrobial activities were investigated, and their minimum inhibitory concentration (MIC) values were determined against P. notatum and S. aureus by the broth microdilution method. Higher cytotoxicity was observed for terezine E against all tested cell lines compared to 14-hydroxyterezine D. Molecular docking results supported the high cytotoxicity of terezine E and showed higher binding affinity with 4CBT with an energy score of 9 kcal/mol. Terezine E showed higher antibacterial and antifungal activities than 14-hydroxyrerezine D: MIC values were 15.45 and 21.73 µg/mL against S. aureus and 8.61 and 11.54 µg/mL against P. notatum, respectively.


Assuntos
Antibacterianos , Staphylococcus aureus , Humanos , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
2.
Braz. j. med. biol. res ; 56: e12404, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1430018

RESUMO

Secondary metabolites produced by endophytes are an excellent source of biologically active compounds. The newly isolated natural products terezine E and 14-hydroxyterezine D are endophytic metabolites exhibiting anticancer activity recently identified by our team (https://doi.org/10.1080/14786419.2018.1489393). In our current study, we evaluated their affinity for binding to the active site of histone deacetylase (PDB ID: 4CBT) and matrix metalloproteinase 9 (PDB ID: 4H3X) by molecular docking using AutoDock Vina software after having tested their cytotoxic activities on three cell lines (human ductal breast epithelial tumor cells (T47D)-HCC1937), human hepatocarcinoma cell line (HepG2)-HB8065), and human colorectal carcinoma cells (HCT-116)-TCP1006, purchased from ATCC, USA)). Additionally, their antimicrobial activities were investigated, and their minimum inhibitory concentration (MIC) values were determined against P. notatum and S. aureus by the broth microdilution method. Higher cytotoxicity was observed for terezine E against all tested cell lines compared to 14-hydroxyterezine D. Molecular docking results supported the high cytotoxicity of terezine E and showed higher binding affinity with 4CBT with an energy score of 9 kcal/mol. Terezine E showed higher antibacterial and antifungal activities than 14-hydroxyrerezine D: MIC values were 15.45 and 21.73 µg/mL against S. aureus and 8.61 and 11.54 µg/mL against P. notatum, respectively.

3.
Malar J ; 18(1): 424, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842893

RESUMO

BACKGROUND: Malaria remains a major public health problem, affecting mainly low-and middle-income countries. The management of this parasitic disease is challenged by ever increasing drug resistance. This study, investigated the therapeutic efficacy, tolerability and safety of artemether-lumefantrine (AL) and artesunate-amodiaquine (AS-AQ), used as first-line drugs to treat uncomplicated malaria in Lambaréné, Gabon. METHODS: A non-randomized clinical trial was conducted between October 2017 and March 2018 to assess safety, clinical and parasitological efficacy of fixed-doses of AL and AS-AQ administered to treat uncomplicated Plasmodium falciparum malaria in children aged from 6 months to 12 years. After 50 children were treated with AL, another 50 children received ASAQ. The 2009 World Health Organization protocol for monitoring of the efficacy of anti­malarial drugs was followed. Molecular markers msp1 and msp2 were used to differentiate recrudescence and reinfection. For the investigation of artemisinin resistant markers, gene mutations in Pfk13 were screened. RESULTS: Per-protocol analysis on day 28 showed a PCR corrected cure rate of 97% (95% CI 86-100) and 95% (95% CI 84-99) for AL and AS-AQ, respectively. The most frequent adverse event in both groups was asthenia. No mutations in the kelch-13 gene associated with artemisinin resistance were identified. All participants had completed microscopic parasite clearance by day 3 post-treatment. CONCLUSION: This study showed that AL and AS-AQ remain efficacious, well-tolerated, and are safe to treat uncomplicated malaria in children from Lambaréné. However, a regular monitoring of efficacy and a study of molecular markers of drug resistance to artemisinin in field isolates is essential. Trial registration ANZCTR, ACTRN12616001600437. Registered 18 November, http://www.anzctr.org.au/TrialSearch.aspx?searchTxt=ACTRN12616001600437p&isBasic=True.


Assuntos
Amodiaquina/uso terapêutico , Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Artemisininas/uso terapêutico , Monitoramento de Medicamentos/estatística & dados numéricos , Malária Falciparum/tratamento farmacológico , Criança , Pré-Escolar , Combinação de Medicamentos , Feminino , Gabão , Humanos , Lactente , Masculino , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/isolamento & purificação , Proteínas de Protozoários/genética
4.
J Neonatal Perinatal Med ; 11(2): 185-190, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29991143

RESUMO

BACKGROUND: Angiogenin is a small protein encoded by the ANG gene. It is activated by tissue hypoxia, and is known to be a potent stimulator of angiogenesis. The role of angiogenic factors in the pathogenesis of HIE is poorly understood, yet, angiogenin may be part of the molecular mechanisms underlying HIE. OBJECTIVE: Our objective was to explore the predictive value of angiogenin as a biochemical marker in early hypoxic ischemic encephalopathy staging. STUDY DESIGN: We prospectively studied 36 full term HIE neonates and 20 non- asphyxia neonates. Cord blood samples from all subjects immediately at delivery were withdrawn. Neurological examination and grading of HIE were performed during the first day of life. RESULTS: Concentrations of cord blood angiogenin were increased in infants with asphyxia when compared txht o controls (P = 0). Within the asphyxia group, the median cord blood angiogenin was significantly higher in stage III encephalopathy patient compared to stage I and stage II (p = 0). There was a negative correlation between pH, HCo3 level and angiogenin in stage II and stage III. CONCLUSION: Angiogenin helps in assessing the severity of HIE in neonates and is promising marker predicting the stage of hypoxia-ischemia so treatment may be initiated earlier.


Assuntos
Biomarcadores/sangue , Sangue Fetal/metabolismo , Hipóxia-Isquemia Encefálica/sangue , Ribonuclease Pancreático/sangue , Peso ao Nascer , Feminino , Humanos , Hipóxia-Isquemia Encefálica/fisiopatologia , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Índice de Gravidade de Doença
5.
Langmuir ; 31(24): 6791-6, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-26035626

RESUMO

The stability of model surfactant bilayers from the poly(ethylene glycol) mono-n-dodecyl ether (C12Ej) family was probed. The surfactant bilayers were formed by the adhesion of emulsion droplets. We generated C12Ej bilayers by forming water-in-oil (w/o) emulsions with saline water droplets, covered by the surfactant, in a silicone and octane oil mixture. Using microfluidics, we studied the stability of those bilayers. C12E1 allowed only short-lived bilayers whereas C12E2 bilayers were stable over a wide range of oil mixtures. At high C12E2 concentration, a two-phase region was displayed in the phase diagram: bilayers formed by the adhesion of two water droplets and Janus-like particles consisting of adhering aqueous and amphiphilic droplets. C12E8 and C12E25 did not mediate bilayer formation and caused phase inversion leading to o/w emulsion. With intermediate C12E4 and C12E5 surfactants, both w/o and o/w emulsions were unstable. We provided the titration of the C12E2 bilayer with C12E4 and C12E5 to study and predict their stability behavior.


Assuntos
Bicamadas Lipídicas/química , Polietilenoglicóis/química , Tensoativos/química , Emulsões/química , Tamanho da Partícula , Propriedades de Superfície
6.
Lab Chip ; 14(18): 3494-7, 2014 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-25025528

RESUMO

Common methods for fabrication of polyelectrolyte microcapsules rely on a multi-step process. We propose a single-step approach to generate polyelectrolyte microcapsules with 1-2 µm shells based on polyelectrolyte complexation across a water/oil droplet interface and study the effect of parameters controlling the polyelectrolyte complexation on shell thickness.


Assuntos
Cápsulas/química , Cápsulas/síntese química , Eletrólitos/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
7.
Obesity (Silver Spring) ; 21(10): 2099-111, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23418049

RESUMO

OBJECTIVE: Metabolic Syndrome (MetS) is a phenotype cluster predisposing to type 2 diabetes and cardiovascular disease. We conducted a study to elucidate the genetic basis underlying linkage signals for multiple representative traits of MetS that we had previously identified at two significant QTLs on chromosomes 3q27 and 17p12. DESIGN AND METHODS: We performed QTL-specific genomic and transcriptomic analyses in 1,137 individuals from 85 extended families that contributed to the original linkage. We tested in SOLAR association of MetS phenotypes with QTL-specific haplotype-tagging SNPs as well as transcriptional profiles of peripheral blood mononuclear cells (PBMCs). RESULTS: SNPs significantly associated with MetS phenotypes under the prior hypothesis of linkage mapped to seven genes at 3q27 and seven at 17p12. Prioritization based on biologic relevance, SNP association, and expression analyses identified two genes: insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) at 3q27 and tumor necrosis factor receptor 13B (TNFRSF13B) at 17p12. Prioritized genes could influence cell-cell adhesion and adipocyte differentiation, insulin/glucose responsiveness, cytokine effectiveness, plasma lipid levels, and lipoprotein densities. CONCLUSIONS: Using an approach combining genomic, transcriptomic, and bioinformatic data we identified novel candidate genes for MetS.


Assuntos
Pleiotropia Genética , Síndrome Metabólica/genética , Locos de Características Quantitativas , Adipócitos/citologia , Adipócitos/metabolismo , Adulto , Composição Corporal , Índice de Massa Corporal , Adesão Celular , Diferenciação Celular , Cromossomos Humanos/genética , Cromossomos Humanos/metabolismo , Estudos de Coortes , Biologia Computacional , Feminino , Perfilação da Expressão Gênica , Estudos de Associação Genética , Ligação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transcriptoma , Proteína Transmembrana Ativadora e Interagente do CAML/genética , Proteína Transmembrana Ativadora e Interagente do CAML/metabolismo , Adulto Jovem
8.
Langmuir ; 28(15): 6291-8, 2012 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-22439743

RESUMO

Water drops dispersed in chloroform and stabilized with phospholipids become adhesive if a bad solvent for lipids, such as silicone oil, is added to the continuous phase. In this way, two sticking drops are separated by a bilayer of phospholipids. By using microfluidic technologies, we probe the stability and properties of such membranes likewise encountered in foams or vesicles. We first establish the stability diagram of adhering drop pairs as a function of the continuous phase composition. We found two regimes of destabilization of the bilayer. The first one concerns a competition between the dynamics of adhesion and the transport of surfactants toward the interfaces that leads to a dilute surfactant coverage. The second one corresponds to a dense surface coverage where the lifetime distribution of the bilayer exponentially decreases as a signature of a nucleation process. In the stable regime, we observe the propagation of adhesion among a concentrated collection of drops. This is another remarkable illustration of the suction consequence when two close deformable objects are pulled apart. Moreover, the present experimental strategy offers a novel way to study the phase diagrams of bilayers from a single phospholipid to a mixture of phospholipids. Indeed, we detect phase transitions at a liquid-liquid interface that are ruled by the amount of bad solvent. Finally, we probe the transport of water molecules through the bilayer and show that its permeability is linked to the adhesion energy that reflects its fluidity.

9.
Phys Rev Lett ; 107(6): 068301, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21902373

RESUMO

Water-in-oil emulsion drops are formed and stabilized with phospholipids which can adhere and form a bilayer. Using microfluidics, adhesive drop pairs are then trapped and submitted to an ac electric field. We observe three distinct states as a function of the adhesion energy and the electric field intensity. The pair can be either stable, though slightly deformed, or unzip and separate, or coalesce. The frontiers between the different states directly reflect vesicle detachment forces and electroporation theories. The experimental approach that we propose for probing liquid interface wetting between monolayers allows us to finely tuned the tension in the bilayer and gives access to bilayer unzipping.


Assuntos
Adesivos/química , Eletricidade , Emulsões/química , Bicamadas Lipídicas/química , Fusão de Membrana , Fosfolipídeos/química , Termodinâmica , Fatores de Tempo , Água/química
10.
Phys Rev Lett ; 102(18): 188304, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19518918

RESUMO

By using microfluidic chips, we investigate the stability regarding coalescence of droplet pairs under an electric field as a function of drop separation and ac field intensity. Three different regimes are found: stable, coalescence, and partial merging. From this, we identify the two breaking scenarios of a one dimensional train of droplets: in one case the coalescence front propagates; in the other case, in which pairs belong to the partial merging regime, the coalescence front can become heterogeneous. From these findings, we can propose a destruction mechanism for a macroscopic emulsion, which includes the packing condition for which total and immediate destruction is effective.

11.
Phys Rev Lett ; 100(2): 024501, 2008 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-18232876

RESUMO

The destabilization process of an emulsion under flow is investigated in a microfluidic device. The experimental approach enables us to generate a periodic train of droplet pairs, and thus to isolate and analyze the basic step of the destabilization, namely, the coalescence of two droplets which collide. We demonstrate a counterintuitive phenomenon: coalescence occurs during the separation phase and not during the impact. Separation induces the formation of two facing nipples in the contact area that hastens the connection of the interfaces prior to fusion. Moreover, droplet pairs initially stabilized by surfactants can be destabilized by forcing the separation. Finally, we note that the fusion mechanism is responsible for a cascade of coalescence events in a compact system of droplets where the separation is driven by surface tension.

12.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-118128

RESUMO

This study is an attempt to determine the incidence of low birth weight [LBW] in Lebanon. Biometric, biomedical and sociobehavioural parameters were investigated. The incidence of LBW showed an upward trend from 1986 to 1990; a peak was observed in 1990 at the height of the war, but rates fell in 1991. Infants born with weights of 2500 to 2999 grams represented about a quarter of live births, although the mean birth weight was higher. The length of gestation was associated with birth weight. More information is needed regarding birth weights at the country level. This would require elimination of the problem of nonhospital births and improvement of the registration system for vital events and of prenatal records


Assuntos
Indicadores Básicos de Saúde , Peso ao Nascer , Recém-Nascido de Baixo Peso
13.
J Basic Microbiol ; 29(3): 131-9, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2746472

RESUMO

The cytogenetic effects of fungal metabolites produced by 113 strains belonging to 36 fungal species and isolated form 5 substrates of commercial poultry feedstuffs were tested for their effect on the growing root meristems of Allium cepa. The fungal metabolites of Paecilomyces canescens, Aspergillus fumigatus, Syncephalastrum racemosum, Aspergillus terreus and Mucor hiemalis strongly suppressed cell division. Metabolites from other strains had less effect on cell division but permitted the appearance of several abnormalities through different mitotic stages. In general, chromosomal aberrations were more obvious with metabolites of Aspergillus species, Mucor circinelloides and Cladosporium cladosporioides. The mutagenic effects produced by these fungal metabolites reflect the risk that might take place through the consumption of these contaminated feedstuffs.


Assuntos
Ração Animal , Micotoxinas/toxicidade , Aves Domésticas , Animais , Divisão Celular/efeitos dos fármacos , Aberrações Cromossômicas , Egito , Contaminação de Alimentos
14.
Mycopathologia ; 89(1): 35-41, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3982490

RESUMO

The fungal flora of wheat flour and baladi bread in upper Egypt were investigated. Most of the isolated fungal species belong to the genus Aspergillus. The presence of non heat resistant fungi of the both flat surfaces of baladi bread, came from contamination after baking and from improper handling at homes. Among the heat resistant fungi, A. fumigatus and A. niger, were recorded to inhabit the spongy crumb although the high temperature of baking process which reached approximately 100 degrees C in the center of the bread. The mutagenic effects of the fungal metabolites of the extract of mouldy Egypt were investigated. Most of the isolated fungal species all stages of mitotic division. The most interesting effect of these fungal metabolites were the induction of tripolar and quadripolar spindle. Multinucleate and polyploid cells were also observed under relatively high concentrations. It was noticed that at either higher concentrations or lower concentrations with long exposure, damaged cells were observed. The hazards involved through the consumption of individuals to such mouldy bread, is accumulation of possible deleterious effects from both long and short term exposure to these toxic metabolites.


Assuntos
Aspergillus/isolamento & purificação , Pão , Microbiologia de Alimentos , Mutação , Micotoxinas/farmacologia , Aspergillus/metabolismo , Aberrações Cromossômicas , Egito , Mitose , Testes de Mutagenicidade , Micotoxinas/biossíntese , Células Vegetais , Plantas/genética
15.
Mycopathologia ; 88(1): 23-6, 1984 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-6440019

RESUMO

The aim of this study was to test infertility of the Egyptian cotton leaf-worm, Spodoptera littoralis. Three concentrations, 0.8, 1.6 and 2.0 micrograms/larva of aflatoxin B-1 and G-1 were applied to the final instar of the larval period. Both B-1 and G-1 induced mutagenic effects on spermatogenesis and morphogenesis which consequently reflected in infertility of Spodoptera littoralis. The phenomenon of mutagenicity was more obvious in larvae treated with G-1 rather than in those treated with B-1. The two analogues were also capable of inducing malformations in sperms. These abnormalities were transmitted to and inherited by the progeny.


Assuntos
Aflatoxinas/farmacologia , Lepidópteros/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Mutagênicos , Aflatoxina B1 , Animais , Larva/efeitos dos fármacos , Masculino , Mariposas/genética , Mutação , Espermatócitos/efeitos dos fármacos
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