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1.
Respir Med Case Rep ; 38: 101674, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35637916

RESUMO

Coronavirus disease-2019 (COVID-19) is a systemic disorder with the lung and the vasculature being the preferred targets. Patients with interstitial lung diseases represent a category at high risk of progression in the case of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 infection, and as such deserve special attention. We first describe the combination of acute exacerbation and pulmonary embolism in an elderly ILD patient after booster anti-COVID-19 mRNA vaccination. Vaccines availability had significantly and safety impacted COVID-19 morbidity and mortality worldwide. Immunization against COVID-19 is indisputable but must not be separated from the awareness of potential adverse effects in fragile patients.

4.
J Nutr Sci Vitaminol (Tokyo) ; 65(Supplement): S54-S58, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31619647

RESUMO

In this research the incapsulation of ferulic acid (FA) in advanced systems of protection with the aim of improving its stability and photostability was studied. Lipoparticles and polymeric microparticles as incapsulation systems were prepared and characterized. Lipoparticles were completely of natural origin, while microparticles were obtained using chitosan as natural polymer. In both systems FA stability was greatly increased and its organoleptic properties in the emulsions did not change.


Assuntos
Ácidos Cumáricos/isolamento & purificação , Composição de Medicamentos/métodos , Tecnologia de Alimentos/métodos , Oryza/química , Quitosana , Emulsões , Humanos , Polímeros
5.
Pharm Dev Technol ; 20(7): 782-790, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24854342

RESUMO

We propose a new approach for photoprotection. 4-Methylbenzylidene camphor (4-MBC), one of the most widely used UV filters, was encapsulated in microspheres, with a view to overcoming problems (percutaneous absorption, photodegradation and lack of lasting effect) arising with organic sunscreens, and to achieve safe photoprotection. We focused on this filter in the light of the Cosmetics Europe opinion concerning its possible effects on the thyroid gland. Microspheres were prepared by emulsification-solvent evaporation, using different amounts of 4-MBC and characterized for morphology, encapsulation efficiency and particle size. The particles were then mixed in O/W emulsions. The in vitro sun protection factors, in vitro release and photostability were investigated and compared with emulsions containing the free sunscreen. The new microspheres offer good morphology and loading (up to 40%), and the same photoprotection as the free filter while at the same time protecting it from photodegradation. The systems also give a slower release from the emulsions.

6.
J Agric Food Chem ; 60(1): 74-80, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22142033

RESUMO

Several new multifunctional molecules derived from natural sources such as amino acids and hydroxycinnamic acids were synthesized. They exhibit various activities such as emulsifying, UV-protecting, and radical scavenging, thereby conforming to the latest requirements for cosmetic ingredients. The synthesis comprises only a few steps: (i) the amino acid, the acid groups of which are protected by esterification, is coupled with ferulic or caffeic acid; (ii) the p-hydroxyl group of the cinnamic derivative reacts with dodecyl bromide in the presence of potassium carbonate (the resulting compounds are highly lipophilic and tested as water/oil (W/O) emulsifiers); (iii) these molecules, by deprotonating the acid groups of the amino acids, with successive salification, are more hydrophilic, with stronger O/W emulsifying properties. The new multifunctional surfactants might prove useful for the treatment of multiple skin conditions, including loss of cellular antioxidants, damage from free radicals, damage from UV, and others.


Assuntos
Hidroxibenzoatos/química , Tensoativos/síntese química , Ácidos Cafeicos/química , Esterificação , Estrutura Molecular , Tensoativos/química
7.
Comput Biol Chem ; 35(3): 159-68, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21704262

RESUMO

To gain structural insight on the interactions between odorants and the human olfactory receptor, we did homology modelling of the receptor structure, followed by molecular docking simulation with ligands. Molecular dynamics simulation on the structures resulting from docking served to estimate the binding free energy of the various odorant families. A correlation with the odorous properties of the ligands is proposed. We also investigated which residues were involved in the binding of a set of properly synthesised ligands and which were required for fitting inside the binding pocket. Olfactive stimulation of the olfactory receptor with odorous molecules was also investigated, using calcium imaging or electrophysiological recordings.


Assuntos
Receptores Odorantes/química , Receptores Odorantes/metabolismo , Algoritmos , Sítios de Ligação , Biologia Computacional , Humanos , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Estrutura Molecular , Odorantes/análise
8.
J Pharm Biomed Anal ; 46(4): 645-52, 2008 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-18207688

RESUMO

Ferulic acid (FA) is a highly effective antioxidant and photo-protective agent, already approved in Japan as a sunscreen, but it is poorly suited for cosmetic application because of its low physicochemical stability. We prepared the inclusion complex of FA with alpha-cyclodextrin by co-precipitation from an aqueous solution, and used (1)H NMR and molecular dynamics to investigate the most probable structure of the inclusion complex. In rotating frame nuclear Overhouser effect spectroscopy (ROESY) experiments FA penetrated the alpha-CD hydrophobic cavity with the alpha,beta-unsaturated part of the molecule and some of its aromatic skeleton. In proton chemical shift measurements of FA and alpha-cyclodextrins we determined the stoichiometry of the association complex (1:1) by Job's method, and its stability constant (K(1:1) 1162+/-140 M(-1)) and described the molecular dynamics of the complex on the basis of theoretical studies. Encapsulation with alpha-cyclodextrin improves (i) the chemical stability of FA against UVB stress (10 MED [Minimal Erythemal Dose: 1 MED=25 mJ/cm(2) for skin phototype II: 30]), since no degradation products are formed after irradiation, and (ii) the bioavailability of FA on the skin, slowing its delivery (Strainer cell model).


Assuntos
Antioxidantes/química , Ácidos Cumáricos/química , alfa-Ciclodextrinas/química , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/administração & dosagem , Estabilidade de Medicamentos , Luz , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Solubilidade , Difração de Raios X , alfa-Ciclodextrinas/administração & dosagem , alfa-Ciclodextrinas/análise
9.
J Pharm Biomed Anal ; 40(4): 875-81, 2006 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-16239093

RESUMO

Ferulic acid (FA) is a well-known antioxidant of natural source with promising properties as photoprotective agent (approved in Japan as sunscreen) and its derivatives (alkyl ferulates) are under screening for the prevention of photoinduced skin tumours. In the present work we describe the preparation of a solid inclusion complex between ferulic acid and gamma-cyclodextrin (gamma-CD) and its characterization by different analytical techniques: differential scanning calorimetry (DSC), X-ray diffractometry (XRD), nuclear magnetic resonance spectroscopy (1H NMR) and by supporting information of molecular modelling. All these approaches indicate that ferulic acid is able to form an association complex with gamma-CD but only 1H NMR and molecular modelling studies give an unequivocal evidence that the antioxidant molecule is embedded into the gamma-CD cavity to form an inclusion complex. In detail it is entrapped inside the hydrophobic core of gamma-CD with the lipophilic aromatic ring and the ethylenic moieties, leaving the more polar functional groups close to wider rim or outside the cavity.


Assuntos
Antioxidantes/química , Ácidos Cumáricos/química , Excipientes/química , gama-Ciclodextrinas/química , Varredura Diferencial de Calorimetria , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Modelos Moleculares
10.
J Agric Food Chem ; 52(21): 6425-32, 2004 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-15479002

RESUMO

The antioxidant activity of some esters of ferulic acid with the linear fatty alcohols C7, C8 (branched and linear), C9, C11, C12, C13, C15, C16, and C18 has been studied in homogeneous and heterogeneous phases. Whereas in homogeneous phase all of the alkyl ferulates possessed similar radical-scavenging abilities, in rat liver microsomes they showed striking differences, the more effective being C12 (7) (IC50 = 11.03 M), linear C8 (3) (IC50 = 12.40 microM), C13 (8) (IC50 = 18.60 microM), and C9 (5) (IC50 = 19.74 microM), followed by C7 (2), C15 (9), C11 (6), branched C8 (4), C16 (10), and C18 (11) (ferulic acid was the less active, IC50 = 243.84 microM). All of the molecules showed similar partition coefficients in an octanol-buffer system. Three-dimensional studies (NMR in solution, modeling in vacuo) indicate that this behavior might be due to a different anchorage of the molecules with the ester side chain to the microsomal phospholipid bilayer and to a consequent different orientation/positioning of the scavenging phenoxy group outside the membrane surface against the flux of oxy radicals.


Assuntos
Antioxidantes/farmacologia , Ácidos Cumáricos/farmacologia , Ésteres/farmacologia , Alquilação , Animais , Antioxidantes/química , Compostos de Bifenilo , Ácidos Cumáricos/química , Ésteres/química , Álcoois Graxos/química , Álcoois Graxos/farmacologia , Espectroscopia de Ressonância Magnética , Masculino , Microssomos Hepáticos/química , Peróxidos/química , Picratos/química , Ratos , Ratos Wistar
11.
J Pharm Biomed Anal ; 35(5): 1241-9, 2004 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-15336368

RESUMO

With the aim to search and design more effective and safe antioxidant molecules to be used as functional ingredients in cosmetic formulations for UV protection, we evaluated the antioxidant/radical scavenging activities of ferulic acid and of some alkyl ferulates in both acellular and cellular systems. Ferulic acid esters, equipotent as antioxidant in homogeneous phase, showed when tested in membranous systems (rat liver microsomes, rat erythrocytes) marked differences in antioxidant potency. The n-C(12) derivative was the most potent, followed by n-C(8), n-C(16) and branched C(8), and then by ferulic acid. A conformational study carried out by NMR and modelling, indicates that the different antioxidant activity of ferulates in membrane models is due to the different spatial conformation and arrangement of the side chain of the molecule, which governs the access and binding to the phospholipid bilayer, the modality of orientation of the scavenging/quenching nucleus (phenol moiety), and hence the overall antioxidant potency of the derivative. These results emphasize the need of analytical studies (NMR and molecular modelling) addressed to the knowledge of the conformational parameters in combination with conventional antioxidant testings for understanding the antioxidant behaviour of a molecule in a biological membrane/system.


Assuntos
Antioxidantes/química , Ácidos Cumáricos/química , Animais , Antioxidantes/farmacologia , Ácidos Cumáricos/farmacologia , Eritrócitos/efeitos dos fármacos , Ésteres/química , Ésteres/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Ratos , Ratos Wistar , Relação Estrutura-Atividade
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