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1.
Anal Chim Acta ; 1232: 340469, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36257759

RESUMO

Several areas such as microbiology, botany, and medicine use genetic information and computational tools to organize, classify and analyze data. However, only recently has it been possible to obtain the chemical ontology of metabolites computationally. The systematic classification of metabolites into classes opens the way for adapting methods that previously used genetic taxonomy to now accept chemical ontology. Community ecology tools are ideal for this adaptation as they have mature methods and enable exploratory data analysis with established statistical tools. This study introduces the Metabology approach, which transforms metabolites into an ecosystem where the metabolites (species) are related by chemical ontology. In the present work, we demonstrate the applicability of this new approach using publicly available data from a metabolomics study of human plasma that searched for prognostic markers of COVID-19, and in an untargeted metabolomics study carried out by our laboratory using Lasiodiplodia theobromae fungal pathogen supernatants.


Assuntos
COVID-19 , Ecossistema , Humanos , Metabolômica/métodos
2.
J Photochem Photobiol B ; 211: 112010, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32890891

RESUMO

Nanotechnology, when applied to PDT's, allows the encapsulation of ZnPc in nanocarriers, producing thus nanoemulsions that permit the use of ZnPc as photosensitizers. The Enterococcus faecalis and methicillin-resistant Staphylococcus aureus (MRSA) are microorganisms present in biofilms which can cause resistant endodontic infections. The objective of this work is the development and characterization of clove essential oil nanoemulsions containing ZnPc. The formulations were developed according to factorial experimental planning and characterized by the determination of the mean drop size, Polydispersity Index (PdI), content, organoleptic characteristics, stability, morphology, cytotoxicity in the dark and evaluation of the photobiological activity. The experimental planning was able to indicate the maximum amount of ZnPc that could be encapsulated in the nanoemulsion while maintaining droplet size <50 nm and PdI < 0.2. The surface plots for the response variables indicated a robust region for the combination of Pluronic® F-127 and clove oil factors. The result of this study was the choice of the nanoemulsion containing ZnPc solution at 5%, clove oil at 5%, Pluronic® F-127 at 10% and will be codified as ZnPc-NE. The nanoemulsion presented a mean diameter of 30.52 nm, PDI < 0.2 and a concentration of 17.5 µg/mL, as well as stability at room temperature for 180 days. TEM showed that the drops are spherical with nanometric size, which corroborates the results of dynamic light scattering. Concerning the photobiological activity, the ZnPc-NE exhibited MIC 1.09 µg/mL for Enterococcus faecalis and 0.065 µg/mL for MRSA (Methicillin-resistant Staphylococcus aureus). ZnPc-NE showed higher photobiological activity than free ZnPc. Besides, cytotoxicity studies showed that blank-NE (nanoemulsions without PS) showed good antimicrobial activity. Thus, clove oil nanoemulsion is an excellent nanocarrier to promote the photobiological activity of the ZnPc against pathogenic microorganisms.


Assuntos
Anti-Infecciosos/química , Emulsões/química , Indóis/química , Nanocápsulas/química , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Administração Oral , Anti-Infecciosos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Óleo de Cravo/química , Composição de Medicamentos , Enterococcus faecalis/efeitos dos fármacos , Humanos , Indóis/farmacologia , Isoindóis , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Poloxâmero/química , Compostos de Zinco
3.
Drug Deliv Transl Res ; 10(6): 1552-1570, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32676952

RESUMO

Leishmaniasis is a neglected infectious disease caused by protozoan parasites from Leishmania genus species, affecting millions of people, in several countries. The current available treatment for cutaneous leishmaniasis (CL) has presented many side effects. In this way, micro- and nanotechnology are important processes, since they may be useful for release profile modulation of CL drugs improving their bioavailability. Amphotericin B (AmB) is a macrolide antibiotic used as a second-choice treatment. This study aimed the development of oil-water nanoemulsions (NEs) containing AmB for topical administration to treat CL. Furthermore, NEs were characterized by their droplet size, morphology, drug content, stability, in vitro release profile, and ex vivo skin permeation. In vitro anti-leishmanial activity using Leishmania amazonensis promastigotes was also evaluated. NEs containing AmB presented droplet size lower than 60 nm with a polydispersity index lower than 0.5. The best AmB-NEs were submitted to stability tests and these formulations presented excellent results after 365 days under refrigeration, confirming the maintenance of the drug content higher than 95%. AmB-NEs displayed slow and controlled AmB kinetic release and low skin permeation. These formulations presented lower cytotoxicity in comparison with free AmB and higher anti-leishmanial effect against L. amazonensis promastigotes. Therefore, the selected AmB-NE formulations, especially AmB-NE01, presented promising results as novel alternatives for CL treatment. Graphical abstract.


Assuntos
Anfotericina B , Antiprotozoários , Leishmaniose Cutânea , Administração Cutânea , Anfotericina B/farmacologia , Animais , Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Camundongos , Células RAW 264.7 , Suínos
4.
J Microbiol Methods ; 175: 105948, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32446912

RESUMO

This article presents a new qualitative method to detect enzyme activity replacing the conventional Agar-Petri dishes. This new method is a simple rapid and low-cost technique that uses 24-well microplates. The detection of hydrolases producing microorganisms in bioprospecting studies by qualitative methods is time consuming, costly and requires a large quantity of strains or enzymatic extracts. Tests with different substrate concentrations (0 to 20 g/L) in agar solution for the enzymatic hydrolysis analysis were performed to determine the best substrate concentrations in 24-well microplates. Other quantitative and analytical methods, such as enzymatic assays and thin layer chromatography, were performed to validate this new method and to compare the relationship between enzymatic activity and substrate degradation. Statistically relevant results were observed for amylase, endoglucanase and polygalacturonase enzymes, even when there was a low substrate concentration in agar, where the halo diameter was high. The results also indicated that the concentrations for efficient enzyme index measurements were 4 g/L carboxymethylcellulose for endoglucanase detection and 8 g/L for amylase and polygalacturonase assays. The results were presented according to the traditional methods for detection of enzymatic activity. This new method can be used as a general test for the detection of important industrial hydrolases. It is a faster and less costly alternative for screening microbial enzyme producing microorganisms and is useful for studying the production of microbial enzymes under different growing conditions.


Assuntos
Amilases/química , Bacillus subtilis/enzimologia , Celulase/química , Ensaios Enzimáticos/métodos , Kluyveromyces/enzimologia , Poligalacturonase/química , Hidrólise
5.
ACS Med Chem Lett ; 10(4): 413-418, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30996772

RESUMO

Trypanosoma cruzi and Leishmania spp. are protozoa of the Trypanosomatidae family, respectively, responsible of the neglected tropical disorders (NTDs) Chagas disease and leishmaniasis. The present pharmacotherapy is often ineffective and exhibits serious side effects. The metalloenzyme carbonic anhydrases (CAs, EC 4.2.1.1) recently identified in these protozoans (α-TcCA and ß-LdcCA) are novel promising targets for chemotherapeutic interventions. Herein, we report a series of N-nitrosulfonamides, as a novel chemotype to yield the target CA isoform selective inhibition over ubiquitous human isozymes. Two derivatives selected among the most active and selective ones for TcCA/LdcCA over off-target CAs were progressed as silver salts to in vitro studies with various developmental forms and spp of Trypanosoma cruzi and leishmania. Excellent values of parasites growth inhibition (IC50) were observed, with some selectivity index (over cytotoxicity for macrophages and Vero cells) being comparable or better than reference drugs. These findings make N-nitrosulfonamides and their salts promising lead compounds for a rational optimization of innovative agents for the treatment of Chagas disease and leishmaniasis based on CA inhibition.

6.
J Enzyme Inhib Med Chem ; 33(1): 850-857, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29708476

RESUMO

The ß-carbonic anhydrase (CA, EC 4.2.1.1) from Leishmania spp. (LdcCA) is effectively inhibited by aromatic/heterocyclic sulphonamides, in the low nanomolar range, but no in vitro antileishmanial activity was detected for such compounds. We formulated some of these sulphonamides as nanoemulsions (NEs) in clove oil, and tested them in vitro against Leishmania infantum MHOM/BR/1974/PP75 and Leishmania amazonensis IFLA/BR/1967/PH8 strains. Interesting inhibitory concentrations IC50 were observed for some of the sulphonamides NEs, with IC50 as low as 3.90 µM (NE-3F) and 2.24 µM (NE-5B) for L. amazonensis and 3.47 µM (NE-5B) for L. infantum. Some of the investigated NEs displayed toxicity for macrophages beyond the parasites. For the same nonoemulsions, a selective index (SI) greater than for Amphotericin B. Haemolytic assay using human red blood cells indicate that the NEs were less cytotoxic than amphotericin B, a widely used antifungal agent. NEs demonstrated to be an excellent strategy for increasing the penetration of these hydrophilic drugs through membranes, with a huge increase of efficacy over the sulphonamide CA inhibitor (CAI) alone.


Assuntos
Antiprotozoários/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Leishmania/efeitos dos fármacos , Nanoestruturas/química , Sulfonamidas/farmacologia , Antiprotozoários/síntese química , Antiprotozoários/química , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Emulsões/síntese química , Emulsões/química , Emulsões/farmacologia , Leishmania/enzimologia , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química
7.
J Enzyme Inhib Med Chem ; 33(1): 139-146, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29192555

RESUMO

Sulfonamide carbonic anhydrase (CA, EC 4.2.1.1) inhibitors targeting the α-class enzyme from the protozoan pathogen Trypanosoma cruzi, responsible of Chagas disease, were recently reported. Although many such derivatives showed low nanomolar activity in vitro, they were inefficient anti-T. cruzi agents in vivo. Here, we show that by formulating such sulfonamides as nanoemulsions in clove (Eugenia caryophyllus) oil, highly efficient anti-protozoan effects are observed against two different strains of T. cruzi. These effects are probably due to an enhanced permeation of the enzyme inhibitor through the nanoemulsion formulation, interfering in this way with the life cycle of the pathogen either by inhibiting pH regulation or carboxylating reactions in which bicarbonate/CO2 are involved. This type of formulation of sulfonamides with T. cruzi CA inhibitory effects may lead to novel therapeutic approaches against this orphan disease.


Assuntos
Antiprotozoários/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Nanoestruturas/química , Sulfonamidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Apoptose/efeitos dos fármacos , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Anidrases Carbônicas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Emulsões/síntese química , Emulsões/química , Emulsões/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Células RAW 264.7 , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Trypanosoma cruzi/crescimento & desenvolvimento
8.
Nanotechnology ; 28(6): 065101, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28071592

RESUMO

Photodynamic therapy (PDT) combines light with photosensitizers (PS) for production of reactive oxygen species (ROS) that can kill infectious microorganisms such as bacteria, fungi and protozoa. The application of nanotechnology has enabled the advancement of PDT because many PS are insoluble in water, necessitating a nanocarrier as a physiologically acceptable carrier. Nanoemulsions are efficient nanocarriers for solubilizing liposoluble drugs, like the PS, in water. Cutaneous (CL) and mucocutaneous leishmaniasis (ML) are caused by different species of the genus Leishmania, transmitted to humans by sandfly bites. Parasites are hosted in skin macrophages producing ulcerative lesions. Thus, a topical treatment, effective and inexpensive, for CL and ML is preferable to systemic interventions. There are topical treatments like paromomycin and amphotericin B, but they have many local side effects or a very high cost, limiting their use. This work aimed to develop a zinc phthalocyanine (photosensitizer) oil-in-water nanoemulsion, essential clove oil and polymeric surfactant (Pluronic® F127) for the formulation of a topical delivery system for use in PDT against Leishmania amazonensis and Leishmania infantum. The nanoemulsion was produced by a high-energy method and characterized by size, polydispersity, morphology, pH, content and stability studies. The toxicity in the dark and the photobiological activity of the formulations were evaluated in vitro for Leishmania and macrophages. The formulation presented was pH compatible with topical use, approximately 30 nm in size, with a polydispersity index ≤0.1 and remained stable at room and refrigerator temperature during the stability study (60 days). The zinc phthalocyanine nanoemulsion is effective in PDT against Leishmania spp.; use against skin infections can be a future application of this topical formulation, avoiding the use of oral or injectable medications, decreasing systemic adverse effects.


Assuntos
Portadores de Fármacos , Indóis/farmacologia , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Administração Cutânea , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Óleo de Cravo/química , Composição de Medicamentos/métodos , Emulsões , Concentração de Íons de Hidrogênio , Indóis/química , Isoindóis , Leishmania infantum/crescimento & desenvolvimento , Leishmania infantum/efeitos da radiação , Leishmania mexicana/crescimento & desenvolvimento , Leishmania mexicana/efeitos da radiação , Luz , Camundongos , Testes de Sensibilidade Microbiana , Nanoestruturas/química , Óxido Nítrico , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Poloxâmero/química , Células RAW 264.7 , Compostos de Zinco
9.
Toxins (Basel) ; 8(11)2016 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-27809242

RESUMO

Piperine is an abundant amide extracted from black pepper seeds which has been shown to have protective effects against cytotoxic and genotoxic carcinogenesis induced by certain chemical carcinogens and aflatoxin B1 (AFB1) in vitro. The aim of this work was to study, in vivo, the antigenotoxic potential of feed-added piperine on broiler chickens experimentally intoxicated with AFB1, using micronucleus and comet assays. The antigenotoxicity assessment of 9-day-old chicks was performed on a total of 60 chickens divided into four groups of 15 broilers each: (C) control, (P) 60 mg·piperine kg-1 feed, (A) 0.5 mg·AFB1·kg-1 body weight, (daily by oral route), and (P + A) co-treatment with piperine and AFB1. The experiment was conducted for 26 days. Chicks intoxicated with AFB1 showed significant genotoxic effects in the first 24 h post intoxication, and the effects remained in the other periods analyzed (48, 72, and 96 h and 26 days of treatment). The DNA damage in peripheral blood cells, the number of erythrocytes with micronuclei, and polychromatic-to-normochromatic erythrocyte ratio were significantly reduced or absent in the piperine/AFB1 group. No significant differences were observed between the group piperine/AFB1 and the control and piperine-alone groups. The addition 60 mg·kg-1 of piperine to the diet of the broiler chicks was safe, promoting beneficial effects in poultry health with respect to the toxic effects 0.5 mg·AFB1·kg-1 body weight.


Assuntos
Aflatoxina B1/toxicidade , Alcaloides/farmacologia , Anticarcinógenos/farmacologia , Benzodioxóis/farmacologia , Carcinógenos/toxicidade , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Ração Animal , Animais , Galinhas , Ensaio Cometa , Dano ao DNA , Dieta/veterinária , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Testes para Micronúcleos , Aumento de Peso/efeitos dos fármacos
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