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1.
Sci Rep ; 14(1): 12608, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824182

RESUMO

Changes in dietary patterns and body weight have become a focus of research in undergraduate students. This study compared breakfast consumption, intake of foods high in saturated fat, and BMI between medical and non-medical students. A comparative cross-sectional study was conducted in 4,561 Peruvian university students, of whom 1,464 (32.1%) were from the medical field and 3,097 (67.9%) from the non-medical field. We compared the frequency of breakfast consumption (categorized as regular: 6 to 7 days/week; occasional: 3 to 5 days/week; and rarely or never: 0 to 2 days/week) and the frequency of consumption of foods high in saturated fat. We created simple and multiple linear and Poisson regression models with robust variance to evaluate the association of the mentioned variables with academic fields. Non-medical students (Adjusted Prevalence Ratio [PR] = 0.92, 95% CI 0.86-0.99; p = 0.008) were less likely to eat breakfast regularly compared to medical students. Likewise, consumption of foods high in saturated fats was higher in non-medical students (B = 1.47, 95% CI 0.91-2.04; p < 0.001) compared to medical students. Similarly, the mean BMI of these students was significantly higher than that of medical students (B = 0.33, 95% CI 0.12-0.53; p = 0.002). Although medical students reported relatively healthy eating habits and a lower BMI, there is a widespread need to promote improved diet and lifestyle among the entire university population to reduce the risks of communicable diseases and improve quality of life.


Assuntos
Índice de Massa Corporal , Desjejum , Comportamento Alimentar , Estudantes de Medicina , Humanos , Feminino , Estudos Transversais , Masculino , Estudantes de Medicina/estatística & dados numéricos , Adulto Jovem , Adulto , Estudantes/estatística & dados numéricos , Gorduras na Dieta , Ácidos Graxos , Adolescente , Universidades , Peru
2.
J Drug Target ; 2(4): 309-16, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7858956

RESUMO

A chemical delivery system (CDS) for enhanced delivery of dopamine to brain tissue, based on a dihydropyridine<==>pyridinium salt redox system, was modified to include an activated carbamate ester. The dihydronicotinate moiety was chemically attached to the amino group of dopamine (DA) by acylation with chloroethyl chloroformate, followed by condensation with sodium nicotinate under mild conditions. The product was selectively N-alkylated at the pyridine ring and subjected to regioselective reduction to the corresponding 1,4-dihydropyridine derivative, DA-CDSac. In vitro stability of the new compound was studied in phosphate buffers at mild acidic, physiological, and mild alkaline pH values. Oxidation studies showed facile conversion of the dihydronicotinate, DA-CDSac, is readily converted to the corresponding quaternary salt, both chemically and enzymatically. In vivo studies in rats did not detect sustained increases in brain levels of the quaternary salt after i.v. dosing with DA-CDSac. However, the new CDS appeared to change spontaneous locomotor activity in rats after i.v. administration which may be due to altered central DA neuronal activity.


Assuntos
Carbamatos/metabolismo , Dopamina/administração & dosagem , Sistemas de Liberação de Medicamentos , Acilação , Alquilação , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Carbamatos/química , Carbamatos/farmacocinética , Carbamatos/farmacologia , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Di-Hidropiridinas/química , Di-Hidropiridinas/metabolismo , Dopamina/metabolismo , Dopamina/farmacocinética , Dopamina/farmacologia , Estabilidade de Medicamentos , Ésteres , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Masculino , Atividade Motora/efeitos dos fármacos , Niacina/química , Oxirredução , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
3.
Eur J Med Chem ; 34(7-8): 551-62, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-11278041

RESUMO

Ester prodrugs of aspirin 1a, ibuprofen 1b, naproxen 1c and indomethacin 1d were synthesized using N-Hydroxymethylsuccinimide (HMSI) 3 and N-hydroxymethylisatin (HMIS) 4 as promoieties to reduce their gastrointestinal toxicity and improve bioavailability. Additionally, the kinetics of hydrolysis of the synthesized prodrugs 5a-d and 6a-d were studied at 37 degrees C in non-enzymatic simulated gastric fluid (SGF; hydrochloric acid buffer pH = 1.2); 0.02 M phosphate buffer (pH = 7.4); 80% human plasma and 10% rat liver homogenate. The results indicate higher chemical stability of the ester prodrugs in non-enzymatic SGF (t(1/2) congruent with 6.5-18.6 h) and rapid conversion to the parent drugs in 80% human plasma (t(1/2) congruent with 11.4-235 min) as well as in 10% rat liver homogenates (t(1/2) congruent with 12.0-90.0 min). As a general pattern, the HMSI esters 5a-d revealed higher chemical stability than the corresponding HMIS analogues 6a-d. The pH-rate profile of 5c and 6a indicated maximum stability of the former at pH = 1.2-8.0 and of the latter at pH = 1.2-4.0. The distribution coefficient (D(7.4)) values of the prodrugs 5a-d, 6a-d and the parent drugs 1a-d in an n-octanol/phosphate buffer (pH = 7.4) system indicated enhanced lipophilic properties of the prodrugs. Furthermore, the HMIS ester prodrugs 6a-d are more lipophilic than the corresponding HMSI derivatives 5a-d. In vivo ulcerogenicity studies using scanning electron microscopy on stomach specimens of rats treated with an oral dose for 4 d revealed that the synthesized ester prodrugs are significantly less irritating to gastric mucosa than the parent drugs. These results suggested HMSI and/or HMIS esters possess good potential as prodrugs with an improved therapeutic index for oral delivery of NSAIDs.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Isatina/química , Pró-Fármacos/síntese química , Succinimidas/química , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/uso terapêutico , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Hidrólise , Ratos , Úlcera Gástrica/induzido quimicamente
4.
J Chem Technol Biotechnol ; 53(4): 329-36, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1368196

RESUMO

Some aryl and/or heterocyclic mercaptans were allowed to react with 8-quinolyl chloroacetate (II), 8-quinolinoxyacetyl chloride (IV) and 3-(2'-chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one (X) in dry benzene and/or sodium hydroxide in absolute ethanol to give corresponding 8-quinolyl-alpha-mercaptoacetate (V), 8-quinolinoxythioacetate (VI) and 3-(2'-arylmercaptoethyl)-2-methyl-4-(3H)quinazolin-4-ones or 3-(2'-heterocyclicmercaptoethyl)-2-methyl-4(3H)-quinazolin-4 -ones (XIa-h). The mercaptans V and XI were subjected to oxidation with hydrogen peroxide/acetic acid mixture (1:2) to afford the corresponding sulfones VII and XII. The structures of the synthesized compounds were elucidated by spectroscopic (IR and 1H-NMR) and elemental analyses. Some of these compounds were tested for their antimicrobial activities in comparison with tetracycline as a reference compound.


Assuntos
Anti-Infecciosos/síntese química , Quinazolinas/síntese química , Quinolinas/síntese química , Sulfetos , Sulfonas , 4-Quinolonas , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Fenômenos Químicos , Físico-Química , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Oxirredução , Quinazolinas/química , Quinazolinas/farmacologia , Quinolinas/química , Quinolinas/farmacologia
5.
Pharmazie ; 50(6): 382-7, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7651974

RESUMO

Esters of Cytarabine-N4-carboxylates 2a-i and succinamates 3a-f were synthesized as prodrugs of cytarabine (Ara-C) with the aim of developing improved derivatives for oral or parentral administration. At pH 2 series 2 showed relative higher stability than 3, while both series of esters revealed matched stability at pH 7. All esters were susceptible to enzymatic hydrolysis by rat plasma and liver homogenate with half lives ranged from 0.14 h to 12 d, and showed improved stability against cytidine deaminase. A parabolic relation was shown between Kobs of enzymatic hydrolysis and Vw. All compounds are more lipophilic than the parent drug, Ara-C.


Assuntos
Citarabina/análogos & derivados , Citarabina/síntese química , Pró-Fármacos/síntese química , Animais , Soluções Tampão , Fenômenos Químicos , Físico-Química , Citarabina/farmacocinética , Citidina Desaminase/metabolismo , Meia-Vida , Concentração de Íons de Hidrogênio , Hidrólise , Técnicas In Vitro , Fígado/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Pró-Fármacos/farmacocinética , Ratos , Ratos Wistar , Espectrofotometria Ultravioleta
6.
Inflammopharmacology ; 6(2): 143-57, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-17694371

RESUMO

Paracetamol (acetaminophen) esters [4a-f] of some acidic NSAIDs were synthesized and evaluated as mutual prodrug forms with the aim of improving the therapeutic index through prevention of the gastrointestinal toxicity. The structures of the synthesized esters were confirmed by IR and (1)H-NMR spectroscopy and their purity was established by elemental analyses and TLC. In-vitro stability studies revealed that the synthesized ester prodrugs 4a-f are sufficiently chemically stable in non-enzymatic simulated gastric fluid (hydrochloric acid buffer of pH 1.3 (t (1/2) approximately 15-45 h)) and in phosphate buffer of pH 7.4 (t (1/2) approximately 4-40 h). In 80% human plasma and 10% rat liver homogenate, the mutual prodrugs were found to be susceptible to enzymatic hydrolysis releasing the corresponding NSAID and paracetamol at relatively faster rates (t (1/2) approximately 15-385 min and 1-140 min, respectively). Calculated log P values indicated that the prodrugs 4a-f are more lipophilic than the parent drugs.In-vivo experiments in rabbits showed higher plasma levels of ibuprofen after oral administration of its ester prodrug 4b compared with those resulting from an equivalent amount of the corresponding physical mixture. Moreover, significant improvement in latency of pain threshold in mice has been observed up to 4 h after po administration of 0.02 mmol/kg of the prodrugs, compared with the corresponding physical mixtures. Gross observations and scanning electromicrographs of the stomach showed that the prodrugs induced very little irritancy in the gastric mucosa of mice after oral administration for 4 days. These results suggest that the synthesized mutual ester prodrugs were characterized by a better therapeutic index than the parent drugs.

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