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1.
Fitoterapia ; 175: 105949, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38583636

RESUMO

Aristolochia plants are emblematic from an ethnopharmacological viewpoint and are know to possess numerous biological properties, including antiseptic. However, the medicinal potential of these species is debatable because of their representative chemical constituents, aristolochic acids (AAs) and aristolactams (ALs), which are associated, for instance, with nephropathy and cancer. These contrasting issues have stimulated the development of approaches intended to detoxification of aristoloquiaceous biomasses, among which is included the bioconversion method using larvae of the specialist phytophagous insect Battus polydamas, previously shown to be viable for chemical diversification and to reduce toxicity. Thus, eleven Aristolochia spp. were bioconverted, and the antimicrobial activities of the plant methanolic extracts and its respective bioconversion products were evaluated. The best results were found for Aristolochia esperanzae, Aristolochia gibertii, and Aristolochia ringens against Bacillus cereus, with MIC ranging from 7.8 to 31.25 µg/mL. These three species were selected for chemical, antioxidant, cytotoxic, hemolytic, and mutagenic analyses. Chemical analysis revealed 65 compounds, 21 of them possible bioconversion products. The extracts showed potential to inhibit the formation and degradation of B. cereus biofilms. Extracts of A. gibertii and its bioconverted biomass showed antioxidant activity comparable to dibutylhydroxytoluene (BHT) standard. Bioconversion decreased the hemolytic activity of A. esperanzae and the cytotoxicities of A. esperanzae and A. gibertii. None of the extracts was found to be mutagenic. The bioactivities of the fecal extracts were maintained, and biocompatibility was improved. Therefore, the results obtained in this study reveal positive expectations about the natural detoxification process of the Aristolochia species.

2.
Int J Biol Macromol ; 235: 123905, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870650

RESUMO

Anadenanthera colubrina, popularly known as white angico, is a species extensively cultivated in Brazil, mainly in the cerrado region, including the state of Piauí. This study examines the development of films composed of white angico gum (WAG) and chitosan (CHI) and containing chlorhexidine (CHX), an antimicrobial agent. The solvent casting method was used to prepare films. Different combinations and concentrations of WAG and CHI were used to obtain films with good physicochemical characteristics. Properties such as the in vitro swelling ratio, the disintegration time, folding endurance, and the drug content were determined. The selected formulations were characterised by scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction, and the CHX release time and antimicrobial activity were evaluated. CHX showed a homogenous distribution in all CHI/WAG film formulations. The optimised films showed good physicochemical properties with 80% CHX release over 26 h, which is considered promising for local treatment of severe lesions in the mouth. Cytotoxicity tests of the films did not show toxicity. The antimicrobial and antifungal effects were very effective against the tested microorganisms.


Assuntos
Anti-Infecciosos , Quitosana , Clorexidina/farmacologia , Clorexidina/química , Quitosana/química , Anti-Infecciosos/farmacologia , Antifúngicos , Brasil , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Mater Sci Eng C Mater Biol Appl ; 130: 112440, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34702525

RESUMO

Erythrosine is a dye approved for medical use that has shown promising photodynamic activity, allowing for the inactivation of microorganisms and activity against malignant cells. Despite the great photodynamic potential, erythrosine exhibits hydrophilicity, negatively impacting its action in biological membranes. Therefore, the incorporation of erythrosine in micellar polymeric systems, such as poloxamers, may overcome this limitation. Moreover, using bioadhesive and thermoresponsive polymers to combine in situ gelation and bioadhesion may enhance retention of this topically applied drug. In this work, mucoadhesive and thermoresponsive micellar systems were prepared containing erythrosine in two states: the native form (ERI) and the disodium salt (ERIs). The systems were evaluated based on the effect of ERI/ERIs on the micellar structure of the binary polymer mixtures. Optimised combinations of poloxamer 407 (polox407) and mucoadhesive sodium carboxymethylcellulose (NaCMC) or hydroxypropyl methylcellulose (HPMC) were used as micellar systems for ERI or ERIs delivery. The systems were studied with respect to theoretical interactions, qualitative composition, morphology, and micellar properties. In silico modelling indicated a higher interaction of the drug with poly(ethylene oxide) (PEO) than poly(propylene oxide) (PPO) fragments of polox407. Systems containing NaCMC displayed a repulsive effect in the presence of erythrosine, due to the polymer's charge density. Both systems could convert the photosensitizer in its monomeric form, ensuring photodynamic activity. In these mixtures, crystallinity, critical micellar temperature and enthalpy of polox407 micellisation were reduced, and micellar size, evaluated by transmission electron microscopy (TEM), showed low impact of ERI/ERIs in HPMC preparations. Aiming toward photodynamic applications, the findings showed how ERI or ERIs can affect the micellar formation of gels composed of 17.5% (w/w) polox407 and 3% (w/w) HPMC or 1% (w/w) NaCMC, important for understating their behaviour and future utilisation as erythrosine delivery systems.


Assuntos
Eritrosina , Poloxâmero , Celulose , Simulação por Computador , Derivados da Hipromelose
4.
Process Saf Environ Prot ; 144: 177-185, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32834561

RESUMO

The increase of the industrialization process brought the growth of pollutant emissions into the atmosphere. At the same time, the demand for advances in aerosol filtration is evolving towards more sustainable technologies. Electrospinning is gaining notoriety, once it enables to produce polymeric nanofibers with different additives and also the obtaining of small pore sizes and fiber diameters; desirable features for air filtration materials. Therefore, this work aims to evaluate the filtration performance of cellulose acetate (CA) nanofibers and cationic surfactant cetylpyridinium bromide (CPB) produced by electrospinning technique for retention of aerosol nanoparticles. The pressure drop and collection efficiency measurements of sodium chloride (NaCl) aerosol particles (diameters from 7 to 300 nm) were performed using Scanning Mobility Particle Sizer (SMPS). The average diameter of the electrospun nanofibers used was 239 nm, ranging from 113 to 398 nm. Experimental results indicated that the nanofibers showed good permeability (10-11 m2) and high-efficiency filtration for aerosol nanoparticles (about 100 %), which can include black carbon (BC) and the new coronavirus. The pressure drop was 1.8 kPa at 1.6 cm s-1, which is similar to reported for some high-efficiency nanofiber filters. In addition, it also retains BC particles present in air, which was about 90 % for 375 nm and about 60 % for the 880 nm wavelength. Finally, this research provided information for future designs of indoor air filters and filter media for facial masks with renewable, non-toxic biodegradable, and potential antibacterial characteristics.

5.
Alcohol Clin Exp Res ; 44(3): 660-668, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31984499

RESUMO

BACKGROUND: Fetal alcohol syndrome (FAS) is a disorder caused by alterations in embryo-fetal development due to prenatal alcohol exposure. It is estimated that between 0.5 and 2 per 1,000 individuals are born with FAS every year. In Brazil, there are few studies addressing the extent of the problem of FAS/fetal alcohol spectrum disorders (FASD); these studies are confined to limited geographic areas. Therefore, we decided to perform a health needs assessment for FAS/FASD in Brazil. METHODS: To estimate the prevalence of FAS and FASD in Brazil, we used information from the literature, which estimates between 0.5 and 2/1,000 births per year for FAS and 10 to 50/1,000 for FASD. RESULTS: We estimated that approximately 1,500 to 6,000 children are born with FAS every year. Considering the whole population, the prevalence would be 95,377 to 380,000 affected people. However, when we consider FASD as a whole, we estimate that between 1,900,000 and 9,500,000 Brazilians might suffer the more severe consequences of alcohol exposure during pregnancy and be living with FASD. CONCLUSION: The results of the current study indicate that FAS and FASD are prevalent disorders in Brazil, and more policies targeting alcohol intake during pregnancy must be developed.


Assuntos
Transtornos do Espectro Alcoólico Fetal/epidemiologia , Avaliação das Necessidades , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/legislação & jurisprudência , Bebidas Alcoólicas/legislação & jurisprudência , Brasil/epidemiologia , Atenção à Saúde , Feminino , Humanos , Gravidez , Fatores Socioeconômicos
6.
An Bras Dermatol ; 91(1): 87-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26982785

RESUMO

Rare cases of hypertrichosis have been associated with topically applied minoxidil. We present the first reported case in the Brazilian literature of generalized hypertrichosis affecting a 5-year-old child, following use of minoxidil 5%, 20 drops a day, for hair loss. The laboratory investigation excluded hyperandrogenism and thyroid dysfunction. Topical minoxidil should be used with caution in children.


Assuntos
Hipertricose/induzido quimicamente , Minoxidil/efeitos adversos , Vasodilatadores/efeitos adversos , Administração Cutânea , Alopecia/tratamento farmacológico , Criança , Feminino , Humanos
7.
Zookeys ; (546): 105-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26798308

RESUMO

Butterflies and moths are found in all terrestrial environments and require efforts for a better understanding of its mega-diversity. These taxa have been the subject of several studies involving phylogeny, ecology and environmental impacts. Nevertheless, several areas in the tropics remain unexplored, resulting in gaps in the taxonomic composition and distribution of butterflies in endemic environments. Therefore, a survey of the butterfly fauna of the Bodoquena Plateau in Brazil was conducted. This area consists of tropical Atlantic Forests, with marginal influences of Savannah, Chaco and Pantanal. Sampling was carried out in 20 locations using Van Someren Rydon traps and insect nets between November 2009 and April 2015. Active collection of individuals was conducted from 9:00 to 17:00h, totaling 240 hours of sampling effort. In total, we registered 768 individuals belonging to 146 species of 98 genera, six families and 18 subfamilies. Nymphalidae was the richest family (84 species), followed by Hesperiidae (22 species), Riodinidae (14 species), Pieridae (12) Papilionidae (11 species) and Lycaenidae (five species). We sampled 239 nymphalids in traps, with 48 species, 30 genera, 15 tribes and five subfamilies. The most common species were Eunica macris (Godart, 1824), Dynamine artemisia (Fabricius, 1793) and Memphis moruus (Fabricius, 1775). Therefore, this study contributes to the knowledge of the Neotropical butterfly diversity and distribution, providing 37 new records and supporting the use of wildlife inventories as important tools for the knowledge of tropical forests biodiversity and conservation.

8.
An Bras Dermatol ; 88(6): 925-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24474101

RESUMO

BACKGROUND: Prevalence of tattoos is around 10-26% in men and 10-22% in women, and can involve negative effects such as: regret, removal attempts, physical and biological changes of the skin and association with some viral diseases. OBJECTIVE: to determine the prevalence, characteristics and factors associated with tattoos in recruiters joining the military. METHODS: the recruiters were examined by dermatologists that documented the presence or absence of tattoos, as well as their sizes, colors, designs and patterns, and whether they needed a parent's consent to get a tattoo. RESULTS: 1,968 recruiters were examined and the prevalence of tattoos was 10.82% (213), 141 (66.20%) had a single tattoo, 44 (20.66%) two tattoos, 15 (7.04%) three tattoos, 9 (4.23%) four tattoos, and 4 (1.88%) had more than four. Of the total sample, 168 (80.77%) reported getting the first tattoo before the age of 18. 158 (74.53%) were monochromatic. In relation to size, 108 (50.70%) had tattoos of up to 10 cm, 75 (35.21%) had tattoos measuring between 11-20 cm, while 30 had ones over 21 cm (14.09%). CONCLUSIONS: The population studied had a high prevalence of tattoos for their age, the percentage of complex (large and polychromatic) tattoos was also high.


Assuntos
Tatuagem/estatística & dados numéricos , Adolescente , Fatores Etários , Brasil , Estudos Transversais , Escolaridade , Humanos , Masculino , Militares/estatística & dados numéricos , Comportamento Social , Inquéritos e Questionários , Tatuagem/efeitos adversos
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