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1.
Dalton Trans ; 46(21): 6994-7004, 2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28513686

RESUMO

The development of effective molecular probes to detect and image the levels of oxidative stress in cells remains a challenge. Herein we report the design, synthesis and preliminary biological evaluation of a novel optical probe to monitor oxidation of thiol groups in cysteine-based phosphatases (CBPs). Following orthogonal protecting approaches we synthesised a new vanadyl complex designed to bind to CBPs. This complex is functionalised with a well-known dimedone derivative (to covalently trap sulfenic acids, SOHs) and a coumarin-based fluorophore for optical visualization. We show that this new probe efficiently binds to a range of phosphatases in vitro with nanomolar affinity. Moreover, preliminary flow cytometry and microscopy studies in live HCT116 cells show that this probe can successfully image cellular levels of sulfenic acids - one of the species resulting from protein oxidative damage.


Assuntos
Complexos de Coordenação/química , Cisteína/análise , Vanádio/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , Cumarínicos/química , Cisteína/química , Espectroscopia de Ressonância de Spin Eletrônica , Células HCT116 , Humanos , Microscopia de Fluorescência , Oxirredução , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/metabolismo , Ligação Proteica
2.
Dalton Trans ; 45(16): 7104-13, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27008377

RESUMO

Vanadium complexes have been previously utilised as potent inhibitors of cysteine based phosphatases (CBPs). Herein, we present the synthesis and characterisation of two new fluorescently labelled vanadyl complexes (14 and 15) with bridged di-picolinic acid ligands. These compounds differ significantly from previous vanadyl complexes with phosphatase inhibition properties in that the metal-chelating part is a single tetradentate unit, which should afford greater stability and scope for synthetic elaboration than the earlier complexes. These new complexes inhibit a selection of cysteine based phosphatases (CBPs) in the nM range with some selectivity. Fluorescence spectroscopic studies (including fluorescence anisotropy) were carried out to demonstrate that the complexes are not simply acting as vanadyl delivery vehicles but they interact with the proteins. Finally, we present preliminary fluorescence microscopy studies to demonstrate that the complexes are cell permeable and localise throughout the cytoplasm of NIH3T3 cells.


Assuntos
Compostos de Dansil/química , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Ácidos Picolínicos/química , Vanadatos/química , Animais , Transporte Biológico , Técnicas de Química Sintética , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Ligantes , Camundongos , Células NIH 3T3 , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Permeabilidade
3.
J Pediatr ; 157(2): 252-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20304413

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of a carbohydrate restricted versus a low fat diet on weight loss, metabolic markers, body composition, and cardiac function tests in severely obese adolescents. STUDY DESIGN: Subjects were randomly assigned to 1 of 2 diets: a high protein, low carbohydrate (20 g/d) diet (high protein, low carbohydrate, HPLC) or low fat (30% of calories) regimen for 13 weeks; close monitoring was maintained to evaluate safety. After the intervention, no clinical contact was made until follow-up measurements were obtained at 24 and 36 weeks from baseline. The primary outcome was change in body mass index Z-score for age and sex (BMI-Z) at 13, 24, and 36 weeks. RESULTS: Forty-six subjects (24 HPLC, 22 in low fat) initiated and 33 subjects completed the intervention; follow-up data were available on approximately half of the subjects. Significant reduction in (BMI-Z) was achieved in both groups during intervention and was significantly greater for the HPLC group (P = .03). Both groups maintained significant BMI-Z reduction at follow-up; changes were not significantly different between groups. Loss of lean body mass was not spared in the HPLC group. No serious adverse effects were observed related to metabolic profiles, cardiac function, or subjective complaints. CONCLUSIONS: The HPLC diet is a safe and effective option for medically supervised weight loss in severely obese adolescents.


Assuntos
Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Obesidade/dietoterapia , Adolescente , Fatores Etários , Apetite , Composição Corporal , Índice de Massa Corporal , Dieta , Feminino , Humanos , Masculino , Segurança , Fatores Sexuais , Resultado do Tratamento
4.
J Epidemiol Community Health ; 58(12): 1036-41, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15547069

RESUMO

STUDY OBJECTIVE: To estimate the annual period prevalence of co-occurring psychiatric illness and substance misuse among patients in primary care. DESIGN: Analysis of the general practice research database. SETTING: England and Wales, 1993-1998. PARTICIPANTS: Registered patients at 230 general practices representing 3.1% of the population. A comorbid case was defined as one with both a psychiatric diagnosis and substance misuse diagnosis (not including alcohol or tobacco) within a calendar year. A potentially chronic comorbid case was one that met this definition and, in addition, was treated in subsequent years for either a psychiatric condition or substance misuse. MAIN RESULTS: The annual period prevalence of comorbidity increased from 50/100 000 patient years of exposure (PYE) to 80/100 000 PYE, an increase of 62% during the study period. Rates of comorbid psychoses, comorbid schizophrenia, and comorbid paranoia increased by 147%, 128%, and 144%. The average age of comorbid cases decreased from 38 years to 34 years. Over 80% of comorbid cases were newly diagnosed in each study year, although many are treated in subsequent years for either psychiatric illness or substance misuse. CONCLUSIONS: This study provides data on the nature and extent of comorbidity in primary care in England and Wales. As the comorbidity rate is increasing by about 10% each year, and as comorbid cases are becoming younger, it is probable that the comorbidity rate will have increased beyond the study end point.


Assuntos
Transtornos Mentais/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Diagnóstico Duplo (Psiquiatria) , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Atenção Primária à Saúde/estatística & dados numéricos , País de Gales/epidemiologia
5.
J Allergy Clin Immunol ; 109(1): 43-50, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11799364

RESUMO

BACKGROUND: It has been suggested that the rise in prevalence of allergic disease in westernized countries is due in part to a decrease in exposure to infections and an increase in the use of antibiotics early in life. OBJECTIVE: The purpose of this investigation was to quantify the relationships between (1) exposure to personal infections, infections in siblings, and use of antibiotics in early life and (2) the incidence of allergic disease. METHODS: Using the West Midlands section of the UK General Practice Research Database, we established a historical birth cohort of children (N = 29,238). For each child, we identified all personal infections and infections in siblings and determined the use of antibiotics in early life; we also noted incident diagnoses of asthma, eczema, and hay fever. The data were analyzed through use of Cox regression. RESULTS: There was no clear protective effect of exposure to either personal infections or infections in siblings with respect to the incidence of allergic disease. Antibiotic exposure was associated with an increased risk of developing allergic disease in a dose-related manner: having 4 or more courses of antibiotics in the first year of life was associated with an increased incidence of asthma (hazard ratio [HR], 3.13; 95% CI, 2.75-3.57), eczema (HR, 1.48; 95% CI, 1.31-1.68), and hay fever (HR, 2.12; 95% CI, 1.68-2.66). However, adjusting for consulting behavior reduced these effects (adjusted HR [95% CI]: asthma, 1.99 [1.72-2.31]; eczema, 1.01 [0.88-1.17]; hay fever, 1.14 [0.88-1.47]). CONCLUSIONS: We found no evidence that exposure to infections reduced the incidence of allergic disease, and infections did not explain the previous findings of a strong birth order effect in this cohort. The use of antibiotics might be associated with early diagnoses of allergic disease.


Assuntos
Antibacterianos/uso terapêutico , Hipersensibilidade/epidemiologia , Infecções/imunologia , Criança , Pré-Escolar , Estudos de Coortes , Bases de Dados como Assunto , Medicina de Família e Comunidade , Feminino , Humanos , Incidência , Lactente , Masculino , Estudos Prospectivos
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