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1.
Food Chem ; 339: 127791, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32860997

RESUMO

Monoterpenes are non-polar secondary metabolites widely used by industry due to their excellent therapeutic, food-ingredient and cosmetic properties. However, their low solubility in water limits their use. In this sense, cyclodextrins (CDs) have been widely used to solve these technological challenges. Thus, this study aims to use (-)-borneol as a monoterpene model to prepare inclusion complexes between ß-CD and hydroxypropyl-ß-CD (HP-ß-CD) through different ways and characterize them in order to choose the best inclusion method to improve physicochemical properties of monoterpenes. To achieve this goal, the samples were prepared by physical mixture (PM), paste complex (PA) and freeze-drying complex (FD) and then, extensively characterized by thermal analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, size particle, X-ray diffraction and nuclear magnetic resonance. The physicochemical results showed that freeze-drying was more effective to form inclusion complexes between (-)-borneol with both CDs. This research highlights the importance of recognizing the best method to prepare inclusion complexes, including food additives as (-)-borneol, to achieve better results in food preparations.


Assuntos
Canfanos/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Varredura Diferencial de Calorimetria , Ingredientes de Alimentos , Liofilização/métodos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Monoterpenos/química , Tamanho da Partícula , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X
2.
Curr Drug Metab ; 18(6): 511-526, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28302028

RESUMO

The discovery of new drugs is generally considered a long and expensive process, which often leads to molecules with low efficacy and high toxicity, which in many cases can be related to metabolism. In an attempt to reduce these failures and the production costs of a new drug, in silico studies have been used to obtain important information about the behavior of these compounds in the metabolism phases: absorption, distribution, metabolism (or biotransformation) and elimination (or excretion). Quantum Mechanical (QM) calculations are based on Schrödinger's equation that can be used to develop models and theoretical parameters able to explain properties observed experimentally. In recent years, there has been an increase in the development of studies involving the application of QM methods to describe properties related to ADMET profile of new compounds. Amongst these, the most commonly used methods are ab initio (Hartree-Fock), Semiempirical (AM1 and PM3) and Density Functional Theory (DFT). The application of these methods allows the modeling of the predicted profile of absorption and elimination of chalcone-chloroquinoline hybrids; the ability of drugs to cross the blood-brain barrier (distribution); proposal of the route for oxidation of several compounds, via CYP450; and to predict the toxicity of pyrethroid analogs. Finally, QM methods can be considered as a valuable tool in the prediction of metabolism when applied to drug discovery.


Assuntos
Modelos Biológicos , Preparações Farmacêuticas/metabolismo , Teoria Quântica , Software
3.
Bioorg Med Chem ; 24(18): 4228-4240, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27475533

RESUMO

In this study, we designed and synthesized a series of thiophen-2-iminothiazolidine derivatives from thiophen-2-thioureic with good anti-Trypanosoma cruzi activity. Several of the final compounds displayed remarkable trypanocidal activity. The ability of the new compounds to inhibit the activity of the enzyme cruzain, the major cysteine protease of T. cruzi, was also explored. The compounds 3b, 4b, 8b and 8c were the most active derivatives against amastigote form, with significant IC50 values between 9.7 and 6.03µM. The 8c derivative showed the highest potency against cruzain (IC50=2.4µM). Molecular docking study showed that this compound can interact with subsites S1 and S2 simultaneously, and the negative values for the theoretical energy binding (Eb=-7.39kcal·mol(-1)) indicates interaction (via dipole-dipole) between the hybridized sulfur sp(3) atom at the thiazolidine ring and Gly66. Finally, the results suggest that the thiophen-2-iminothiazolidines synthesized are important lead compounds for the continuing battle against Chagas disease.


Assuntos
Tiazolidinas/farmacologia , Tiofenos/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Cisteína Endopeptidases , Inibidores de Cisteína Proteinase/síntese química , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/toxicidade , Glicina/química , Camundongos , Simulação de Acoplamento Molecular , Octoxinol , Proteínas de Protozoários/antagonistas & inibidores , Tiazolidinas/síntese química , Tiazolidinas/toxicidade , Tiofenos/síntese química , Tiofenos/toxicidade , Tioureia/análogos & derivados , Tioureia/síntese química , Tioureia/farmacologia , Tioureia/toxicidade , Tripanossomicidas/síntese química , Tripanossomicidas/toxicidade
4.
Arq. bras. med. vet. zootec ; 66(5): 1531-1538, Sep-Oct/2014. tab
Artigo em Português | LILACS | ID: lil-729758

RESUMO

Foram conduzidos dois ensaios para avaliar a utilização do farelo do farelo integral de arroz parboilizado (FIAP) em rações para leitões na fase de creche. No primeiro, foram utilizados 14 suínos machos castrados para a avaliação nutricional do ingrediente em ensaio de digestibilidade. O delineamento experimental foi o inteiramente ao acaso, com dois tratamentos e sete repetições por tratamento. O FIAP apresenta 17,15% de PB, elevado teor em fibras (33,75% de FDN e 15,91% de FDA) e teor reduzido de energia metabolizável, próximo a 2320kcal/kg. No segundo experimento, foram utilizados 60 leitões machos castrados, com o objetivo de avaliar o desempenho zootécnico, a ocorrência de diarreia e a viabilidade econômica do farelo de arroz parboilizado. O delineamento experimental foi em blocos ao acaso, com cinco tratamentos (0, 4, 8, 12 e 16% de inclusão) e seis repetições. Não houve diferença significativa entre o tratamento controle e os tratamentos teste (P>0,05), assim como para a análise de regressão, em que os crescentes níveis de inclusão do ingrediente não resultaram em piora no desempenho (P>0,05). O FIAP pode ser incluído até o nível de 16% em rações para leitões na fase de creche...


Two assays were conducted to evaluate the parboiled rice bran in piglet's diets in the nursery phase. In the first, 14 male castrated piglets were allotted to determine the nutritional value of parboiled rice bran in a digestibility assay. A completely randomized design, with 2 treatments and 7 replicates per treatment were used. The parboiled rice bran presents 17.15% of CP and high fiber content (33.75% of NDF and 15.91% of ADF) and low metabolizable energy (2320kcal/kg). In the second assay, 60 male castrated piglets were used to evaluate the effect of inclusion on productive performance, diarrhea incidence and economic viability of parboiled rice bran. A randomized block design was used, with 5 treatments (0, 4, 8, 12 and 16%) and 6 replicates. There was no difference between treatments and control treatment as well as in regression analysis, and the increasing levels of parboiled rice bran did not reduce the performance of animals. In conclusion, parboiled rice bran can be included up to 16% in diets for piglets in the nursery phase...


Assuntos
Animais , Oryza , Ração Animal/análise , Suínos , Fenômenos Fisiológicos da Nutrição Animal , Diarreia , Economia dos Alimentos
5.
Rev. bras. farmacogn ; 12(supl.1): 110-111, 2002. ilus
Artigo em Inglês | LILACS | ID: lil-528774

RESUMO

This work proposes thermal characterization, of the biflorine, orto-quinon of Capraria biflora L., through the TG and DSC photovisual data. The thermogravimetric results showed that the decomposition reaction biflorine occurs three steps under air atmosphere, The DSC of biflorin presented five peaks relating to phase transitions. The DSC photovisual system demonstrated changes in biflorin.

6.
G Chir ; 20(5): 238-40, 1999 May.
Artigo em Italiano | MEDLINE | ID: mdl-10380366

RESUMO

Infection of implantable cardioverter defibrillator (ICD) is a devastating event. In an effort to more fully understand ICD infection, the authors reviewed patients records recommending a strategy for management based on their satisfactory experience. From March 1993 through May 1998, 85 ICD were implanted in 64 male and 21 female patients. Transmediastinal approach was performed in 8 (9.5%) cases and transvenous in 77 (91.5%). All device-related infections were examined. Seven (8.25%) device-related infections occurred with a mean time interval of 3 months. In all cases bacterial infection was demonstrated. All infections involved the generator with or without other components involvement. First approach was conservative in all cases but it wasn't successful. Then the authors always used a surgical therapy, in 3 cases removing electrodes by traction and in 4 resorting to cardiopulmonary bypass (CPB). Two deaths were registered. Explantation of ICD resolved in all cases infective complications with no early or additional reinfections. In the last cases with devices implanted by transvenous approach and subpectoral generator implant, no infective complications were observed. In authors experience a complete removal of the ICD generator as well as of all its components is to be preferred as soon as the infections develops.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Adulto , Idoso , Desfibriladores Implantáveis/estatística & dados numéricos , Contaminação de Equipamentos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Falha de Prótese , Infecções Relacionadas à Prótese/terapia , Infecções por Pseudomonas/terapia , Estudos Retrospectivos , Infecções Estafilocócicas/terapia
7.
Minerva Ginecol ; 50(6): 265-76, 1998 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-9763819

RESUMO

BACKGROUND: A sample of 100 women was clinically examined for a very various vulvovaginal symptomatology and an individual diagnosis of vulvovaginitis of different aetiology was established. METHODS: All women were treated with antibiotic and/or antimycotic drugs on the basis of individual diagnosis. Sixty women had only this treatment, while 40 women had also a supplementary treatment with a cleanser emulsion characterized by physiologic pH value and an antiseptic activity due to a vegetable extract (Saugella Attiva, Lab. Guieu). The symptomatologic changes due to the two treatments were compared. RESULTS AND CONCLUSIONS: Combined treatment (drug + antiseptic) obtained better results mostly in subjective symptomatology; this combined treatment was very useful in the recovery of the Doderlein population.


Assuntos
Vagina/fisiologia , Vulvovaginite/microbiologia , Adulto , Antifúngicos/uso terapêutico , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Micoses/prevenção & controle , Recidiva , Vagina/química , Vulvovaginite/tratamento farmacológico , Vulvovaginite/prevenção & controle
8.
Eur J Obstet Gynecol Reprod Biol ; 69(2): 109-13, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8902442

RESUMO

The aim of this study was to investigate the short and long term effects of continuous percutaneous administration of estradiol (E2) cream on skeletal turnover in women in surgical postmenopause. Forty women were randomly divided into two groups, one treated with a single daily application of 3 mg/day E2 cream continuously for 12 months, the other receiving placebo cream. Forearm densitometry was performed before and at the end of treatment. Serum E2, osteocalcin (BGP), alkaline posphatase (AP) and urinary N-telopeptide of type I collagen (NTX) were also measured at baseline, month 4 and 12 of the protocol. At month 4, bone turnover was also assessed by evaluating 99mtechnetium-methylene diphosphonate (99mTc-MDP) skeletal uptake. Changes in E2, BGP, AP and NTX as well as 99mTc-MDP skeletal uptake in hormone group vs. placebo were significant after 4 months of treatment. At month 12, proximal site densitometry showed no variation in either group whereas the percentage of variation in distal site measurements resulted significantly different with an increase in the hormone group and a reduction in the placebo group. In conclusion continuous percutaneous administration of E2 cream was effective in rapidly reducing bone turnover in postmenopausal women and in counteracting the accelerated postmenopausal bone loss.


Assuntos
Osso e Ossos/metabolismo , Estradiol/administração & dosagem , Pós-Menopausa/metabolismo , Absorciometria de Fóton , Administração Cutânea , Fosfatase Alcalina/sangue , Fosfatase Alcalina/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/urina , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Creatinina/sangue , Creatinina/metabolismo , Densitometria , Método Duplo-Cego , Estradiol/sangue , Estradiol/metabolismo , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Osteocalcina/sangue , Osteocalcina/efeitos dos fármacos , Osteocalcina/metabolismo , Pós-Menopausa/efeitos dos fármacos , Estudos Prospectivos , Cintilografia , Compostos Radiofarmacêuticos/metabolismo , Absorção Cutânea , Medronato de Tecnécio Tc 99m/metabolismo , Fatores de Tempo
9.
Hepatology ; 5(6): 1201-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4065825

RESUMO

Seven groups of female Sprague-Dawley rats (approximately 200 gm initial body weight) were injected i.p. with a single subcarcinogenic dose of diethylnitrosamine (40 mg per kg body weight) between 8 to 10 hr after partial hepatectomy, and after a recovery period of 3 weeks (herein called induction stage) received 0.05% phenobarbital in the diet for the rest of the experiment (promotion stage). The rats were fed a 20% casein-based diet containing 0.16 ppm of selenium or the same diet supplemented with 4 or 6 ppm of selenium as sodium selenite. The effects of these three dietary regimens were tested when administered 9 to 11 days before and during induction, 1 week before and during promotion or during the entire experiment. Pair-feeding conditions were used to minimize influences due to differences in food intake and growth. Despite similarities in food intakes, the growth rates in groups receiving the 6 ppm-selenium diet during promotion or during the entire experiment were in general significantly lower than in rats fed the 4 ppm-selenium diet or the 0.16 ppm-selenium basal diet. Survival rates were also significantly reduced in rats fed the 4 and 6 ppm-selenium diets during promotion or during the entire experiment. In rats killed at the 19th week for interim assessment of the experiment's progress, the stereologically analyzed numerical and volumetric densities of hepatic premalignant hyperplastic nodules did not differ significantly between groups. All the remaining rats were killed at the 46th week.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Neoplasias Renais/prevenção & controle , Neoplasias Hepáticas Experimentais/prevenção & controle , Selênio/administração & dosagem , Ração Animal , Animais , Peso Corporal/efeitos dos fármacos , Dietilnitrosamina , Feminino , Hepatectomia , Hiperplasia/patologia , Rim/efeitos dos fármacos , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/patologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Selênio/farmacologia , Fatores de Tempo
10.
Nutr Cancer ; 7(1-2): 25-36, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4070005

RESUMO

Four groups of weanling male Wistar rats (Groups A-D) received diethylnitrosamine (DEN, 40 ppm) in their drinking water for four weeks; after a recovery period of two weeks, they received (for the rest of the experiment) phenobarbital (PB, 500 ppm) added to a Torula yeast-based diet containing 0.17 ppm of selenium. Dietary selenium (2 ppm), as sodium selenite, was given to Group B one week before and during DEN treatment, to Group C one week before and during PB treatment, and to Group D during the entire experiment. Groups A and E received the unsupplemented diet, whereas Group E was not treated with DEN or PB. Pair-feeding conditions were used to minimize possible influences of differences in food intake and growth. Rats were killed at the 19th and 24th weeks after the experiment began. No significant differences were found in food and fluid intakes or in growth rates among the groups. Livers in Group E were histologically normal, whereas preneoplastic and neoplastic lesions were found in all other groups. In rats killed at the 19th and 24th weeks, the numerical and the volumetric densities of preneoplastic lesions did not differ significantly between all the groups. Similarly, the incidence of hepatocellular carcinomas only detected at 24 weeks was not significantly different between the groups. These results indicated that in this particular model of hepatocarcinogenesis, the dietary supplementation of 2 ppm of selenium did not modify the development of preneoplasia and carcinomas.


Assuntos
Neoplasias Hepáticas Experimentais/prevenção & controle , Selênio/administração & dosagem , Animais , Peso Corporal/efeitos dos fármacos , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Metildimetilaminoazobenzeno , Tamanho do Órgão/efeitos dos fármacos , Fenobarbital , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/prevenção & controle , Ratos , Ratos Endogâmicos , Ácido Selenioso
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