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1.
Bioorg Chem ; 92: 103243, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31518756

RESUMO

The first total synthesis of juniperanol, the tricyclic sesquiterpenoid enantiomer of α-cedrol is described. The synthesis relies on stereoselective gold-catalyzed Ohloff-type propargylic ester rearrangement performed on a 10 g scale, and a carbocationic cascade in the presence of acetyl methanesulfonate. The ability of juniperanol to interfere in glucose processes in different cell types is described.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucose/metabolismo , Hipoglicemiantes/síntese química , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Juniperus/química , Camundongos , Estrutura Molecular , Madeira/química
2.
Acta Orthop Belg ; 83(1): 1-7, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-29322887

RESUMO

The purpose is to identify risk factors of functional outcome following proximal humerus open reduction and internal fixation. Patients treated for proximal humerus fractures with open reduction and internal fixation were enrolled in a prospective data registry. Patients were evaluated for function using the Disability of the Arm, Shoulder and Hand score for 12 months and as available beyond 12 months. Univariate analyses were conducted to identify variables associated with functional outcome. Significant variables were included in a multivariate regression predicting functional outcome. Demographics and minimum of 12 month follow-up were available for 129 patients (75%). Multiple regression demonstrated postoperative complication (B=8.515 p=0.045), education level (B=-6.269p<0.0005), age (B=0.241p=0.049) and Charlson Comorbidity Index (B=6.578, p=0.001) were all significant predictors of functional outcome. Orthopaedic surgeons can use education level, comorbidities, age, and postoperative complication information to screen patients for worse outcomes, establish expectations, and guide care.


Assuntos
Fixação Interna de Fraturas , Redução Aberta , Fraturas do Ombro/cirurgia , Placas Ósseas , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Medição de Risco , Fatores de Risco , Resultado do Tratamento
3.
Biochim Biophys Acta ; 1541(3): 150-60, 2001 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11755209

RESUMO

Some biological properties of new bifunctional conjugates designed for drug targeting were evaluated through in vitro experiments. Eight peptidylcyclodextrin compounds were used, which correspond to modified beta- or gamma-cyclodextrin (CD) grafted on neuropeptide substance P (SP) or a shorter derivative (SP(4-11)). Using anti-SP and anti-CD antibodies as molecular probes, we showed that the main structural features of the two moieties of these adducts were preserved. Binding experiments, using CHO cells expressing the human SP-specific NK1 receptor, demonstrated the functionality of all peptidylcyclodextrin derivatives, which exhibited IC50 values in a 10(-9)-10(-7) M range. All compounds were able to induce a pharmacological response, triggering phosphatidylinositol turnover with EC50 values in the same range as the natural ligand. Moreover, autoradiography analysis of rat spinal corn sections proved that [125I]SP binding was dose-dependently displaced by one selected compound (a gamma-CD-SP), showing a similar affinity of this adduct for the rat neurokinin 1 receptor. Our observations demonstrate that these peptidylcyclodextrins efficiently target NK1 receptor-expressing cells.


Assuntos
Ciclodextrinas/farmacologia , Sistemas de Liberação de Medicamentos , Receptores da Neurocinina-1/efeitos dos fármacos , Substância P/análogos & derivados , beta-Ciclodextrinas , gama-Ciclodextrinas , Animais , Anticorpos/imunologia , Autorradiografia , Ligação Competitiva , Células CHO , Cricetinae , Ciclodextrinas/química , Ciclodextrinas/imunologia , Desenho de Fármacos , Estrutura Molecular , Receptores da Neurocinina-1/biossíntese , Receptores da Neurocinina-1/genética , Proteínas Recombinantes/biossíntese , Substância P/química , Substância P/imunologia
4.
J Pharm Sci ; 88(3): 302-5, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10052987

RESUMO

We have developed a highly sensitive enzyme immunoassay for 6-monoamino-beta-CD (mono(6-amino-6-deoxy)cyclomaltoheptaose) and its parent compound (beta-CD) with a detection limit in the 100 pg/mL range. The polyclonal antibodies obtained are highly specific for the beta-cyclodextrin core and do not recognize other cyclic cyclodextrins (i.e., alpha- and gamma-CD) or linear analogues. This enzyme immunoassay can be used to quantify 6-monoamino-beta-CD in rat urine and plasma. Using this immunoassay, we have evaluated the main pharmacokinetic parameters of 6-monoamino-beta-CD after iv administration to the rat of a 25 mg/kg dose. Since this method is strictly specific to the native beta-CD form, we have demonstrated that the molecule rapidly disappeared from plasma but is probably distributed in the tissues. The urinary route appears as the predominant way of elimination since almost all the administered drug is recovered in urine. Finally, analysis of the same molecule after oral administration to the rat (25 mg/kg) demonstrates low plasma levels and that about 1% of the administered dose is excreted in urine. These experiments demonstrate the high stability of the beta-CD core irrespective of the method of administration. This immunological method could provide relevant information on the fate of beta-CD and some derivatives for drug delivery using different modes of administration (oral, parenteral, transmucosal, or dermal).


Assuntos
Ciclodextrinas/farmacocinética , beta-Ciclodextrinas , Administração Oral , Animais , Ciclodextrinas/administração & dosagem , Técnicas Imunoenzimáticas , Injeções Intravenosas , Masculino , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade
5.
Carbohydr Res ; 327(4): 385-93, 2000 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-10990023

RESUMO

The mechanism of action of purified apple pectin methylesterase on pectin (degree of methoxylation: DM 75) and methoxylated homogalacturonans (DM 70 and 90) was studied at pH 7.0 (optimal pH of the enzyme) and at pH 4.5 (close to the pH of apple juice). Different interchain distributions of the free carboxyl groups were obtained at pH 7.0 and 4.5: high-performance ion exchange chromatography indicated a typical single chain mechanism at pH 7.0, but a mechanism differing from the single and multiple chain ones at pH 4.5. However, the same intrachain distribution of the newly demethoxylated galacturonic acid residues was observed for both pHs by 1H NMR. The high content of consecutive de-esterified or consecutive esterified galacturonic acid residues suggested that apple PME acted with a multiple attack mechanism on the pectic substrate. The degree of multiple attack of the enzyme was greater than or equal to 10-11.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Rosales/enzimologia , Hidrolases de Éster Carboxílico/química , Cromatografia por Troca Iônica , Esterificação , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Ressonância Magnética , Pectinas/metabolismo , Proteínas de Plantas
6.
Nat Commun ; 4: 2701, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24165568

RESUMO

Liquids exhibit specific properties when they are adsorbed in nanoporous structures. This is particularly true in the context of supercapacitors, for which an anomalous increase in performance has been observed for nanoporous electrodes. This enhancement has been traditionally attributed in experimental studies to the effect of confinement of the ions from the electrolyte inside sub-nanometre pores, which is accompanied by their partial desolvation. Here we perform molecular dynamics simulations of realistic supercapacitors and show that this picture is correct at the microscopic scale. We provide a detailed analysis of the various environments experienced by the ions. We pick out four different adsorption types, and we, respectively, label them as edge, planar, hollow and pocket sites upon increase of the coordination of the molecular species by carbon atoms from the electrode. We show that both the desolvation and the local charge stored on the electrode increase with the degree of confinement.

8.
Pharm Res ; 16(9): 1407-11, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10496657

RESUMO

PURPOSE: Because of its ability to form complexes with drugs, gamma-cyclodextrin is of great potential value in pharmaceutical formulations. The biological fate of y-cyclodextrin must therefore be considered in safety evaluation, using sensitive and specific methods applicable to biological fluids. METHODS: Antibodies were raised against gamma-cyclodextrin, allowing the development of a new enzyme immunoassay. The analytical characteristics of this assay were evaluated. Rats were given a single intravenous 25 mg/kg dose of gamma-cyclodextrin. Plasma and urine samples were collected and assayed. RESULTS: This new enzyme immunoassay was sensitive (limit of detection close to 94 pg/mL) and suitable for quantification of gamma-cyclodextrin in urine and plasma after methanol extraction. The use of different linear and cyclic compounds demonstrated the high specificity of the assay. After i.v. administration, the concentration of gamma-cyclodextrin rapidly decreased in the plasma while the molecule was probably distributed into the tissues. Although urinary elimination predominates, only 50% of the injected gamma-cyclodextrin was recovered in urine, suggesting enzymatic degradation and/or tissular storage. CONCLUSIONS: This assay may provide important information on the fate of gamma-cyclodextrin inclusion complexes dedicated to drug-delivery using various modes of administration (oral, parenteral, transmucosal or dermal).


Assuntos
Ciclodextrinas/farmacocinética , Técnicas Imunoenzimáticas/métodos , alfa-Ciclodextrinas , gama-Ciclodextrinas , Acetilcolinesterase/metabolismo , Animais , Anticorpos , Líquidos Corporais , Reações Cruzadas , Ciclodextrinas/imunologia , Ciclodextrinas/urina , Sistemas de Liberação de Medicamentos , Injeções Intravenosas , Masculino , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade
11.
Br Med J ; 2(6091): 896, 1977 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-922351
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