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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5864-5867, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019308

RESUMO

Obesity is a complex disease and its prevalence depends on multiple factors related to the local socioeconomic, cultural and urban context of individuals. Many obesity prevention strategies and policies, however, are horizontal measures that do not depend on context-specific evidence. In this paper we present an overview of BigO (http://bigoprogram.eu), a system designed to collect objective behavioral data from children and adolescent populations as well as their environment in order to support public health authorities in formulating effective, context-specific policies and interventions addressing childhood obesity. We present an overview of the data acquisition, indicator extraction, data exploration and analysis components of the BigO system, as well as an account of its preliminary pilot application in 33 schools and 2 clinics in four European countries, involving over 4,200 participants.


Assuntos
Obesidade Infantil , Saúde Pública , Adolescente , Criança , Europa (Continente) , Humanos , Obesidade Infantil/epidemiologia , Instituições Acadêmicas
2.
Mol Pharm ; 16(6): 2418-2429, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-30991003

RESUMO

Silica mesoporous microparticles loaded with both rhodamine B fluorophore (S1) or hydrocortisone (S2), and capped with an olsalazine derivative, are prepared and fully characterized. Suspensions of S1 and S2 in water at an acidic and a neutral pH show negligible dye/drug release, yet a notable delivery took place when the reducing agent sodium dithionite is added because of hydrolysis of an azo bond in the capping ensemble. Additionally, olsalazine fragmentation induced 5-aminosalicylic acid (5-ASA) release. In vitro digestion models show that S1 and S2 solids are suitable systems to specifically release a pharmaceutical agent in the colon. In vivo pharmacokinetic studies in rats show a preferential rhodamine B release from S1 in the colon. Moreover, a model of ulcerative colitis is induced in rats by oral administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) solutions, which was also used to prove the efficacy of S2 for colitis treatment. The specific delivery of hydrocortisone and 5-ASA from S2 material to the colon tissue in injured rats markedly lowers the colon/body weight ratio and the clinical activity score. Histological studies showed a remarkable reduction in inflammation, as well as an intensive regeneration of the affected tissues.


Assuntos
Colite/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Dióxido de Silício/química , Animais , Hidrocortisona/química , Masculino , Mesalamina/química , Mesalamina/uso terapêutico , Ratos , Ratos Wistar , Rodaminas/química , Rodaminas/uso terapêutico
3.
Int J Pharm ; 561: 93-101, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30817986

RESUMO

A colon targeted drug delivery system for inflammatory bowel diseases (IBD), consisting in budesonide loaded mesoporous silica microparticles functionalized with a selective azo-molecular gate (M-Bud), has been evaluated for in vivo efficacy. Experimental colitis in male Wistar rats was induced by rectal instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS). M-Bud was orally administered to the rats as a suspension in water. Colon/body weight ratio, clinical activity score, and histological evaluation were used as inflammatory indices to measure the performance of the microparticles. The formulation was compared with a suspension prepared from the commercial drug Entocord®. Statistical analyses of all scores indicate that the controlled release of budesonide in colon from M-Bud showed efficacy similar to that of Entocord in the healing of induced colitis in rats.


Assuntos
Budesonida/uso terapêutico , Colite/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Dióxido de Silício/uso terapêutico , Animais , Compostos Azo/química , Compostos Azo/uso terapêutico , Budesonida/química , Colite/induzido quimicamente , Colite/patologia , Masculino , Ratos , Dióxido de Silício/química , Ácido Trinitrobenzenossulfônico
4.
R Soc Open Sci ; 5(8): 180873, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225077

RESUMO

Mesoporous silica microparticles were prepared, loaded with the dye safranin O (M-Saf) or with the drug budesonide (M-Bud) and capped by the grafting of a bulky azo derivative. Cargo release from M-Saf at different pH values (mimicking those found in the gastrointestinal tract) in the absence or presence of sodium dithionite (a reducing agent mimicking azoreductase enzyme present in the colon) was tested. Negligible safranin O release was observed at pH 6.8 and 4.5, whereas a moderate delivery at pH 1.2 was noted and attributed to the hydrolysis of the urea bond that linked the azo derivative onto the external surface of the inorganic scaffold. Moreover, a marked release was observed when sodium dithionite was present and was ascribed to the rupture of the azo bond in the molecular gate. Budesonide release from M-Bud in the presence of sodium dithionite was also assessed by ultraviolet-visible spectroscopy and high performance liquid chromatography measurements. In addition, preliminary in vivo experiments with M-Saf carried out in mice indicated that the chemical integrity of the microparticles remained unaltered in the stomach and the small intestine, and safranin O seemed to be released in the colon.

5.
J Control Release ; 281: 58-69, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29753956

RESUMO

Magnetic mesoporous silica microparticles were loaded with safranin O (S1) and with hydrocortisone (S2) and the outer surface functionalized with a bulky azo derivative bearing urea moieties. Aqueous suspensions of both solids at pH 7.4 showed negligible payload release whereas a marked delivery was observed in the presence of sodium dithionite due to the rupture of the azo bonds. Besides, a moderate cargo release was observed at acidic pH due to the hydrolysis of the urea bonds that linked the azo derivative onto the external surface of the inorganic scaffolds. In vitro digestion models showed that S1 and S2 microparticles could be used for the controlled release of payload in the reducing colon environment (in which azoreductase enzymes are present). On the other hand, in vivo pharmacokinetic studies in rats showed that safranine O release from S1 microparticles was concentrated in colon. The performance of S2 microparticles for the treatment of colitis in rats (induced by oral administration of a 2,4,6-trinitrobenzenesulfonic acid solution) was tested. The controlled release of hydrocortisone from S2 in the colon of injured rats induced marked reduction in colon/body weight ratio and in clinical activity score. Also, histological studies showed a marked decrease in inflammation followed by intensive regeneration and almost normal mucosal structure of the individuals treated with S2. Besides, the use of a magnetic belt increased the therapeutic performances of S2 due to an enhanced retention time of the particles in the colon.


Assuntos
Colo/efeitos dos fármacos , Portadores de Fármacos/química , Doenças Inflamatórias Intestinais/tratamento farmacológico , Nanopartículas de Magnetita/química , Fenazinas/farmacocinética , Dióxido de Silício/química , Animais , Colite/tratamento farmacológico , Colo/metabolismo , Liberação Controlada de Fármacos , Humanos , Magnetismo , Masculino , Ácido Oleico/química , Tamanho da Partícula , Porosidade , Ratos Wistar , Propriedades de Superfície , Ácido Trinitrobenzenossulfônico/química
6.
Molecules ; 23(2)2018 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-29439396

RESUMO

Magnetic micro-sized mesoporous silica particles were used for the preparation of a gated material able to release an entrapped cargo in the presence of an azo-reducing agent and, to some extent, at acidic pH. The magnetic mesoporous microparticles were loaded with safranin O and the external surface was functionalized with an azo derivative 1 (bearing a carbamate linkage) yielding solid S1. Aqueous suspensions of S1 at pH 7.4 showed negligible safranin O release due to the presence of the bulky azo derivative attached onto the external surface of the inorganic scaffold. However, in the presence of sodium dithionite (azoreductive agent), a remarkable safranin O delivery was observed. At acidic pH, a certain safranin O release from S1 was also found. The pH-triggered safranin O delivery was ascribed to the acid-induced hydrolysis of the carbamate moiety that linked the bulky azo derivatives onto the mesoporous inorganic magnetic support. The controlled release behavior of S1 was also tested using a model that simulated the gastro intestinal tract.


Assuntos
Compostos Azo/química , Nanopartículas/química , Dióxido de Silício/química , Cloretos , Colo/metabolismo , Ditionita/química , Portadores de Fármacos , Liberação Controlada de Fármacos , Compostos Férricos , Compostos Ferrosos , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Magnetismo , Microesferas , Oxirredução , Fenazinas/administração & dosagem , Porosidade , Propriedades de Superfície
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