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1.
Braz J Biol ; 84: e275974, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39046047

RESUMO

The therapeutic potential of medicinal plants is known as an alternative in treatment of human affections; in effect, the conventional application of these medicinal sources has several limitations like low bioavailability, solubility and stability, which affect its pharmacological efficacy. In recent decades, extraordinary advances have been made in new drug delivery systems using nanocarriers. This work consisted in determining the in vitro antifungal activity of the methanolic extract of Euphorbia tirucalli formulated in polymeric nanoparticles. The antifungal activity was determined by the microdilution method in 96-well microplates, applying nanoparticles loaded with plant extract (NP-Ext) obtained by nanoprecipitation on clinical isolates of Trichophyton rubrum and T. interdigitalis. Regarding the nanoparticles, the lots used did not present significant differences in their physicochemical characteristics, with a size of 91.885 ± 1.621nm, polydispersity index of 0.152 ± 0.025 and Z-potential of -6.047 ± 0.987. The quantification of the extract in the polymeric matrix was determined by infrared spectroscopy (FTIR), where an efficiency and encapsulation percentage of 22.15 ± 0.82 and 2.95 ± 0.11, respectively, were obtained. The in vitro antifungal activity of the crude and formulated extract was obtained calculating the Minimum Inhibitory Concentration (MIC) of each one; a MIC of 125 µg/mL was obtained against T. rubrum and T. interdigitalis with the crude extract, while a MIC value of 55.55 and 0.1 µg/mL was obtained with NP-Ext, respectively, against these same. Conclusions: biological activity is closely linked to the phytochemical profile of the extract; while the improvement of said potential with the NP-Ext with the dosage form was directly related to the physicochemical characteristics of the nanocarrier.


Assuntos
Antifúngicos , Euphorbia , Testes de Sensibilidade Microbiana , Nanopartículas , Extratos Vegetais , Euphorbia/química , Antifúngicos/farmacologia , Antifúngicos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Nanopartículas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Trichophyton/efeitos dos fármacos , Polímeros/farmacologia , Polímeros/química , Arthrodermataceae
2.
Arch Soc Esp Oftalmol (Engl Ed) ; 97(7): 363-369, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35577741

RESUMO

PURPOSE: Interleukin-6 (IL-6) is a proinflammatory cytokine with pleiotropic effects which has been related to primary open angle glaucoma (POAG) due to its particular effect of protecting the retinal ganglion cells (RGc) from the apoptosis. Different single nucleotide polymorphisms (SNP) have been associated with POAG. The aim of this study was to determine whether an association between IL-6 rs1800795 (-174 G>C) SNP and a higher risk for POAG is present in western Mexican population. METHODS: One hundred and sixty-five unrelated Mexican mestizo patients with POAG and 108 control subjects were included. Genomic DNA was extracted from leukocytes and purified, followed by genotyping and amplification by polymerase chain reaction (PCR) with Taqman Biosystem probes. Allelic and genotypic diversity was evaluated between cases and control subjects. RESULTS: There was no statistically significant association between allele and genotype frequencies, neither with dominant nor recessive genetic association models (p > 0.05). CONCLUSION: Even though there is a role of IL6 in the pathophysiology of POAG, our results ruled out the association between IL-6 and the rs1800795 SNP showing not to be an index of higher risk for POAG in Mexican population.


Assuntos
Glaucoma de Ângulo Aberto , Interleucina-6 , Polimorfismo de Nucleotídeo Único , Frequência do Gene , Genótipo , Glaucoma de Ângulo Aberto/genética , Humanos , Interleucina-6/genética , México/epidemiologia
3.
Nat Commun ; 11(1): 3759, 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753582

RESUMO

Almost all chemical elements have been made by nucleosynthetic reactions in various kind of stars and have been accumulated along our cosmic history. Among those elements, the origin of phosphorus is of extreme interest because it is known to be essential for life such as we know on Earth. However, current models of (Galactic) chemical evolution under-predict the phosphorus we observe in our Solar System. Here we report the discovery of 15 phosphorus-rich stars with unusual overabundances of O, Mg, Si, Al, and Ce. Phosphorus-rich stars likely inherit their peculiar chemistry from another nearby stellar source but their intriguing chemical abundance pattern challenge the present stellar nucleosynthesis theoretical predictions. Specific effects such as rotation or advanced nucleosynthesis in convective-reactive regions in massive stars represent the most promising alternatives to explain the existence of phosphorus-rich stars. The phosphorus-rich stars progenitors may significantly contribute to the phosphorus present on Earth today.

4.
Semergen ; 46(4): 270-276, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-32044200

RESUMO

Urticaria is a common cause for patient consultations in Primary Care (PC). However, the optimal approach to managing urticaria in PC is controversial and not well-established. For this reason, there is a clear need to clarify the causes of urticaria and to develop treatment protocols to improve urticaria management in the PC setting. The present work has been developed with this objective. A group of experts in PC and dermatology, with specific expertise in treating urticaria, have reviewed the main clinical guidelines and publications on urticaria in order to develop clear, interdisciplinary recommendations on managing urticaria. In this article, consensus-based recommendations are presented that include simple, practical diagnostic, and treatment algorithms. These guidelines will help to optimise the management of patients with urticaria, increasing their quality of life and reducing the socioeconomic costs associated with this illness.


Assuntos
Urticária , Doença Crônica , Consenso , Humanos , Atenção Primária à Saúde , Qualidade de Vida , Encaminhamento e Consulta
6.
Artigo em Inglês | MEDLINE | ID: mdl-23603577

RESUMO

A series of 33 different polycyclic aromatic hydrocarbons (PAHs) were studied by far infrared spectroscopy (terahertz spectroscopy) in the spectral range comprised between 600 and 50 cm(-1). In addition to common PAHs like naphthalene, anthracene, phenanthrene, fluoranthene, picene, pyrene, benzo[α]pyrene, and perylene, also quite unusual PAHs were studied like tetracene, pentacene, acenaphtene, acenaphtylene, triphenylene, and decacyclene. A series of alkylated naphthalenes and anthracenes were studied as well as methypyrene. Partially or totally hydrogenated PAHs were also object of the present investigation, ranging from tetrahydronaphthalene (tetralin) to decahydronaphthalene (decalin), 9,10-dihydroanthracene, 9,10-dihydrophenanthrene, hexahydropyrene, and dodecahydrotriphenylene. Finally, the large and quite rare PAHs coronene, quaterrylene, hexabenzocoronene, and dicoronylene were studied by far infrared spectroscopy. The resulting reference spectra were used in the interpretation of the chemical structure of asphaltenes (as extracted from a heavy petroleum fraction and from bitumen), the chemical structures of other petroleum fractions known as DAE (distillate aromatic extract) and RAE (residual aromatic extract), and a possible interpretation of components of the chemical structure of anthracite coal. Asphaltenes, heavy petroleum fractions, and coal were proposed as model compounds for the interpretation of the emission spectra of certain proto-planetary nebulae (PPNe) with a good matching in the mid infrared between the band pattern of the PPNe emission spectra and the spectra of these oil fractions or coal. Although this study was finalized in an astrochemical context, it may find application also in the petroleum and coal chemistry.


Assuntos
Petróleo , Hidrocarbonetos Policíclicos Aromáticos/química , Antracenos/química , Carvão Mineral , Hidrogenação , Naftalenos/química , Compostos Policíclicos/química , Pirenos/química , Espectrofotometria Infravermelho
7.
Science ; 314(5806): 1751-4, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17095658

RESUMO

A long-debated issue concerning the nucleosynthesis of neutron-rich elements in asymptotic giant branch (AGB) stars is the identification of the neutron source. We report intermediate-mass (4 to 8 solar masses) AGB stars in our Galaxy that are rubidium-rich as a result of overproduction of the long-lived radioactive isotope (87)Rb, as predicted theoretically 40 years ago. This finding represents direct observational evidence that the (22)Ne(alpha,n)(25)Mg reaction must be the dominant neutron source in these stars. These stars challenge our understanding of the late stages of the evolution of intermediate-mass stars and would have promoted a highly variable Rb/Sr environment in the early solar nebula.

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