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1.
J Clin Invest ; 132(11)2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35642632

RESUMO

Although aging and lung injury are linked to the development of idiopathic pulmonary fibrosis (IPF), the underlying pathognomonic processes predisposing to fibrotic lesions remain largely unknown. A deficiency in the ability of type 2 alveolar epithelial cell (AEC2) progenitors to regenerate and repair the epithelia has been proposed as a critical factor. In this issue of the JCI, Liang et al. identify a deficiency in the zinc transporter SLC39A8 (ZIP8) in AEC2s and in the subsequent activation of the sirtuin SIRT1 that predisposes to decreased AEC2 renewal capacity and enhanced lung fibrosis in both IPF and aging lungs. Interestingly, the authors demonstrate the efficacy of modulating dietary zinc levels, suggesting the need for clinical trials to evaluate the therapeutic potential of dietary supplementation and the development of pharmacological modulation of the Zn/ZIP8/SIRT1 axis for treatment.


Assuntos
Proteínas de Transporte de Cátions , Fibrose Pulmonar Idiopática , Sirtuína 1 , Células Epiteliais Alveolares/metabolismo , Proteínas de Transporte , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Humanos , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Sirtuína 1/genética , Sirtuína 1/metabolismo
2.
Eur Respir J ; 55(4)2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32184317

RESUMO

Accumulating evidence highlights links between iron regulation and respiratory disease. Here, we assessed the relationship between iron levels and regulatory responses in clinical and experimental asthma.We show that cell-free iron levels are reduced in the bronchoalveolar lavage (BAL) supernatant of severe or mild-moderate asthma patients and correlate with lower forced expiratory volume in 1 s (FEV1). Conversely, iron-loaded cell numbers were increased in BAL in these patients and with lower FEV1/forced vital capacity (FVC) ratio. The airway tissue expression of the iron sequestration molecules divalent metal transporter 1 (DMT1) and transferrin receptor 1 (TFR1) are increased in asthma, with TFR1 expression correlating with reduced lung function and increased Type-2 (T2) inflammatory responses in the airways. Furthermore, pulmonary iron levels are increased in a house dust mite (HDM)-induced model of experimental asthma in association with augmented Tfr1 expression in airway tissue, similar to human disease. We show that macrophages are the predominant source of increased Tfr1 and Tfr1+ macrophages have increased Il13 expression. We also show that increased iron levels induce increased pro-inflammatory cytokine and/or extracellular matrix (ECM) responses in human airway smooth muscle (ASM) cells and fibroblasts ex vivo and induce key features of asthma in vivo, including airway hyper-responsiveness (AHR) and fibrosis, and T2 inflammatory responses.Together these complementary clinical and experimental data highlight the importance of altered pulmonary iron levels and regulation in asthma, and the need for a greater focus on the role and potential therapeutic targeting of iron in the pathogenesis and severity of disease.


Assuntos
Asma , Animais , Humanos , Interleucina-13 , Ferro , Pulmão , Pyroglyphidae
3.
Food Chem Toxicol ; 124: 431-438, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30582954

RESUMO

Botanical-derived dietary supplements have widespread use in the general population. The complex and variable nature of botanical ingredients and reports of adverse responses have led to concern for negative human health impacts following consumption of these products. Toxicity testing of the vast number of available products, formulations, and combinations is not feasible due to the time and resource intensive nature of comprehensive testing. Methods are needed to assess the safety of a large number of products via more efficient frameworks. Identification of toxicologically-active constituents is one approach being used, with many advantages toward product regulation. Bioassay-guided fractionation (BGF) is the leading approach used to identify biologically-active constituents. Most BGF studies with botanicals focus on identifying pharmacologically-active constituents for drug discovery or botanical efficacy research. Here, we explore BGF in a toxicological context, drawing from both efficacy and poisonous plant research. Limitations of BGF, including loss of mixture activity and bias toward abundant constituents, and recent advancements in the field (e.g., biochemometrics) are discussed from a toxicological perspective. Identification of active constituents will allow better monitoring of market products for known toxicologically-active constituents, as well as surveying human exposure, two important steps to ensuring the safety of botanical dietary supplements.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Alimentos/análise , Preparações de Plantas/análise , Animais , Bioensaio/métodos , Suplementos Nutricionais/toxicidade , Humanos , Metabolômica/métodos , Preparações de Plantas/toxicidade
5.
Birth Defects Res ; 110(10): 883-896, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29460393

RESUMO

Dietary supplement and natural product use is increasing within the United States, resulting in growing concern for exposure in vulnerable populations, including young adults and women of child-bearing potential. Vinpocetine is a semisynthetic derivative of the Vinca minor extract, vincamine. Human exposure to vinpocetine occurs through its use as a dietary supplement for its purported nootropic and neuroprotective effects. To investigate the effects of vinpocetine on embryo-fetal development, groups of 25 pregnant Sprague-Dawley rats and 8 pregnant New Zealand White rabbits were orally administered 0, 5, 20, or 60 mg vinpocetine/kg and 0, 25, 75, 150, or 300 mg/kg daily from gestational day (GD) 6-20 and GD 7-28, respectively. Pregnant rats dosed with vinpocetine demonstrated dose-dependent increases in postimplantation loss, higher frequency of early and total resorptions, lower fetal body weights, and fewer live fetuses following administration of 60 mg/kg, in the absence of maternal toxicity. Additionally, the rat fetuses displayed dose-dependent increases in the incidences of ventricular septum defects and full supernumerary thoracolumbar ribs. Similarly, albeit at higher doses than the rats, pregnant rabbits administered vinpocetine displayed an increase in postimplantation loss and fewer live fetuses (300 mg/kg), in addition to significantly lower fetal body weights (≥75 mg/kg). In conclusion, vinpocetine exposure resulted in similar effects on embryo-fetal development in the rat and rabbit. The species differences in sensitivity and magnitude of response is likely attributable to a species difference in metabolism. Taken together, these data suggest a potential hazard for pregnant women who may be taking vinpocetine.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Fetal/efeitos dos fármacos , Alcaloides de Vinca/efeitos adversos , Anormalidades Induzidas por Medicamentos , Animais , Suplementos Nutricionais/efeitos adversos , Feminino , Peso Fetal/efeitos dos fármacos , Feto/efeitos dos fármacos , Exposição Materna , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Coelhos , Ratos , Ratos Sprague-Dawley
6.
Ophthalmology ; 123(4): 771-82, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26795295

RESUMO

PURPOSE: To describe the associations of physical and demographic factors with Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated intraocular pressure (IOPcc) in a British cohort. DESIGN: Cross-sectional study within the UK Biobank, a large-scale multisite cohort study in the United Kingdom. PARTICIPANTS: We included 110 573 participants from the UK Biobank with intraocular pressure (IOP) measurements available. Their mean age was 57 years (range, 40-69 years); 54% were women, and 90% were white. METHODS: Participants had 1 IOP measurement made on each eye using the Ocular Response Analyzer noncontact tonometer. Linear regression models were used to assess the associations of IOP with physical and demographic factors. MAIN OUTCOME MEASURES: The IOPg and IOPcc. RESULTS: The mean IOPg was 15.72 mmHg (95% confidence interval [CI], 15.70-15.74 mmHg), and the mean IOPcc was 15.95 mmHg (15.92-15.97 mmHg). After adjusting for covariates, IOPg and IOPcc were both significantly associated with older age, male sex, higher systolic blood pressure (SBP), faster heart rate, greater myopia, self-reported glaucoma, and colder season (all P < 0.001). The strongest determinants of both IOPg and IOPcc were SBP (partial R(2): IOPg 2.30%, IOPcc 2.26%), followed by refractive error (IOPg 0.60%, IOPcc 1.04%). The following variables had different directions of association with IOPg and IOPcc: height (-0.77 mmHg/m IOPg; 1.03 mmHg/m IOPcc), smoking (0.19 mmHg IOPg, -0.35 mmHg IOPcc), self-reported diabetes (0.41 mmHg IOPg, -0.05 mmHg IOPcc), and black ethnicity (-0.80 mmHg IOPg, 0.77 mmHg IOPcc). This suggests that height, smoking, diabetes, and ethnicity are related to corneal biomechanical properties. The increase in both IOPg and IOPcc with age was greatest among those of mixed ethnicities, followed by blacks and whites. The same set of covariates explained 7.4% of the variability of IOPcc but only 5.3% of the variability of IOPg. CONCLUSIONS: This analysis of associations with IOP in a large cohort demonstrated that some variables clearly have different associations with IOPg and IOPcc, and that these 2 measurements may reflect different biological characteristics.


Assuntos
Córnea/fisiologia , Pressão Intraocular/fisiologia , Tonometria Ocular , Adulto , Idoso , Envelhecimento/fisiologia , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Bases de Dados Factuais , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Estudos Prospectivos , Refração Ocular/fisiologia , Inquéritos e Questionários , Reino Unido
7.
Br J Sports Med ; 50(8): 458-63, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26612846

RESUMO

AIM: To explore the effects of exercise (water-based or land-based) and/or manual therapies on pain in adults with clinically and/or radiographically diagnosed hip osteoarthritis (OA). METHODS: A systematic review and meta-analysis was performed, with patient reported pain assessed using a visual analogue scale (VAS) or the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain subscale. Data were grouped by follow-up time (0-3 months=short term; 4-12 months=medium term and; >12 months=long term), and standardised mean differences (SMD) with 95% CIs were used to establish intervention effect sizes. Study quality was assessed using modified PEDro scores. RESULTS: 19 trials were included. Four studies showed short-term benefits favouring water-based exercise over minimal control using the WOMAC pain subscale (SMD -0.53, 95% CI -0.96 to -0.10). Six studies supported a short-term benefit of land-based exercise compared to minimal control on VAS assessed pain (SMD -0.49, 95% CI -0.70 to -0.29). There were no medium (SMD -0.23, 95% CI -0.48 to 0.03) or long (SMD -0.22, 95% CI -0.51 to 0.06) term benefits of exercise therapy, or benefit of combining exercise therapy with manual therapy (SMD -0.38, 95% CI -0.88 to 0.13) when compared to minimal control. CONCLUSIONS: Best available evidence indicates that exercise therapy (whether land-based or water-based) is more effective than minimal control in managing pain associated with hip OA in the short term. Larger high-quality RCTs are needed to establish the effectiveness of exercise and manual therapies in the medium and long term.


Assuntos
Terapia por Exercício , Manipulações Musculoesqueléticas , Osteoartrite do Quadril/terapia , Manejo da Dor/métodos , Humanos , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Toxicol Appl Pharmacol ; 263(2): 138-47, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22687605

RESUMO

Black cohosh rhizome (Actaea racemosa) is used as a remedy for pain and gynecological ailments; modern preparations are commonly sold as ethanolic extracts available as dietary supplements. Black cohosh was nominated to the National Toxicology Program (NTP) for toxicity testing due to its widespread use and lack of safety data. Several commercially available black cohosh extracts (BCE) were characterized by the NTP, and one with chemical composition closest to formulations available to consumers was used for all studies. Female B6C3F1/N mice and Wistar Han rats were given 0, 15 (rats only), 62.5 (mice only), 125, 250, 500, or 1000 mg/kg/day BCE by gavage for 90 days starting at weaning. BCE induced dose-dependent hematological changes consistent with a non-regenerative macrocytic anemia and increased frequencies of peripheral micronucleated red blood cells (RBC) in both species. Effects were more severe in mice, which had decreased RBC counts in all treatment groups and increased micronucleated RBC at doses above 125 mg/kg. Dose-dependent thymus and liver toxicity was observed in rats but not mice. No biologically significant effects were observed in other organs. Puberty was delayed 2.9 days at the highest treatment dose in rats; a similar magnitude delay in mice occurred in the 125 and 250 mg/kg groups but not at the higher doses. An additional uterotrophic assay conducted in mice exposed for 3 days to 0.001, 0.01, 0.1, 1, 10, 100 and 500 mg/kg found no estrogenic or anti-estrogenic activity. These are the first studies to observe adverse effects of BCE in rodents.


Assuntos
Cimicifuga/química , Doenças Hematológicas/induzido quimicamente , Extratos Vegetais/toxicidade , Maturidade Sexual/efeitos dos fármacos , Anemia Macrocítica/induzido quimicamente , Animais , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/patologia , Estrogênios/metabolismo , Etanol/química , Feminino , Doenças Hematológicas/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Extratos Vegetais/administração & dosagem , Ratos , Ratos Wistar , Índice de Gravidade de Doença , Especificidade da Espécie , Timo/efeitos dos fármacos , Timo/patologia , Testes de Toxicidade
9.
Food Chem Toxicol ; 49(9): 2116-24, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21651954

RESUMO

Androstenedione was marketed as a dietary supplement to increase muscle mass during training. Due to concern over long-term use, the NTP evaluated the subchronic and chronic toxicity and carcinogenicity of androstenedione in male and female F344/N rats and B6C3F1 mice. In subchronic studies, dose limiting effects were not observed. A chronic (2-year) exposure by gavage at 10, 20, or 50 mg/kg in rats and male mice, and 2, 10, or 50 mg/kg in female mice (50 mg/kg, maximum feasible dose) was conducted. Increased incidences of lung alveolar/bronchiolar adenoma and carcinoma occurred in the 20 mg/kg male rats and increases in mononuclear cell leukemia occurred in the 20 and 50 mg/kg female rats, which may have been related to androstenedione administration. In male and female mice, androstenedione was carcinogenic based upon a significant increase in hepatocellular tumors. A marginal increase in pancreatic islet cell adenomas in male (50 mg/kg) and female (2, 10, 50 mg/kg) mice was considered to be related to androstenedione administration. Interestingly, incidences of male rat Leydig cell adenomas and female rat mammary gland fibroadenomas decreased. In conclusion, androstenedione was determined to be carcinogenic in male and female mice, and may have been carcinogenic in rats.


Assuntos
Androstenodiona/toxicidade , Carcinógenos/toxicidade , Animais , Testes de Carcinogenicidade , Relação Dose-Resposta a Droga , Feminino , Masculino , Camundongos , Ratos , Ratos Endogâmicos F344
10.
J Nutr Biochem ; 22(1): 95-100, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20392623

RESUMO

Allergic airways disease (AAD) is associated with an increased influx of eosinophils to the lungs, mucus hypersecretion and Th2 cytokine production. Dietary antioxidant supplementation may alter cytokine responses and thus allergic inflammation. Lycopene is a potent dietary antioxidant. The objective of this study was to investigate the effects of lycopene, on allergic inflammation, in a mouse model of AAD. BALB/c mice receiving lycopene supplement or control were intraperitoneally sensitised and intranasally challenged with ovalbumin (OVA) to induce AAD. The effect of supplementation on inflammatory cell influx into bronchoalveolar lavage fluid, lung tissue and blood, mucus-secreting cell numbers in the airways, draining lymph node OVA-specific cytokine release, serum IgG1 levels and lung function in AAD was assessed. Supplementation reduced eosinophilic infiltrates in the bronchoalveolar lavage fluid, lung tissue and blood, and mucus-secreting cell numbers in the airways. The OVA-specific release of Th2-associated cytokines IL-4 and IL-5 was also reduced. We conclude that supplementation with lycopene reduces allergic inflammation both in the lungs and systemically, by decreasing Th2 cytokine responses. Thus, lycopene supplementation may have a protective effect against asthma.


Assuntos
Asma/imunologia , Asma/prevenção & controle , Carotenoides/administração & dosagem , Suplementos Nutricionais , Mediadores da Inflamação/metabolismo , Eosinofilia Pulmonar/prevenção & controle , Células Th2/imunologia , Animais , Asma/fisiopatologia , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Células Cultivadas , Citocinas/metabolismo , Imunoglobulina G/sangue , Pulmão/imunologia , Pulmão/patologia , Pulmão/fisiopatologia , Licopeno , Linfonodos/citologia , Linfonodos/imunologia , Linfonodos/metabolismo , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Fitoterapia , Eosinofilia Pulmonar/imunologia , Células Th2/metabolismo
11.
Curr Drug Targets ; 11(8): 957-70, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20412045

RESUMO

Glucocorticoids are the mainstay of asthma management and effectively treat acute exacerbations of asthma. However, a small subset of asthmatics, usually with severe asthma, respond poorly even to systemic administration of high-dose glucocorticoids and this condition is termed "steroid-resistant asthma". This cohort, although small, accounts for approximately 50% of total health care cost for asthma. New investigations into the mechanisms of glucocorticoid action have broadened and deepened our understanding of glucocorticoid resistance. Here we review the importance and characteristics of steroid resistant asthma, the mechanisms that mediate the function of glucocorticoids and that lead to the development of this disease and potential therapies to reverse resistance to treatment. Cellular and molecular factors, receptors and complex signalling pathways have all been implicated. Indeed, based on molecular biological studies, excessive activation of intracellular transcription factors, impaired histone deacetylase, and epigenetic (such as miR-18 and miR-124a) as well as other factors (e.g. vitamin D, P-glycoprotein 170, and macrophage migration inhibitory factor and T helper 17 cells and factors related to innate immunity (such as IFN-gamma and LPS)) may result in glucocorticoid resistance. A thorough understanding of the pathogenesis of steroid resistant asthma will help to develop more efficacious agents for the treatment of the disease.


Assuntos
Antiasmáticos/farmacologia , Asma/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Animais , Antiasmáticos/efeitos adversos , Antiasmáticos/uso terapêutico , Asma/fisiopatologia , Desenho de Fármacos , Resistência a Medicamentos , Glucocorticoides/efeitos adversos , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Índice de Gravidade de Doença , Transdução de Sinais/efeitos dos fármacos
12.
J Immunol ; 182(9): 5393-9, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19380786

RESUMO

The Ym1/2 lectin is expressed abundantly in the allergic mouse lung in an IL-13-dependent manner. However, the role of Ym1/2 in the development of allergic airways disease is largely unknown. In this investigation, we show that treatment of mice with anti-Ym1/2 Ab during induction of allergic airways disease attenuated mediastinal lymph node production of IL-5 and IL-13. Ym1/2 was found to be expressed by dendritic cells (DCs) in an IL-13-dependent manner and supplementation of DC/CD4(+) T cell cocultures with Ym1/2 enhanced the ability of IL-13(-/-) DCs to stimulate the secretion of IL-5 and IL-13. Affinity chromatography identified 12/15(S)-lipoxygenase (12/15-LOX) as a Ym1/2-interacting protein and functional studies suggested that Ym1/2 promoted the ability of DCs to stimulate cytokine production by inhibiting 12/15-LOX-mediated catalysis of 12-hydroxyeicosatetraenoic acid (12(S)-HETE). Treatment of DC/CD4(+) T cell cultures with the 12/15-LOX inhibitor baicalein enhanced, whereas 12(S)-HETE inhibited the production of Th2 cytokines. Notably, delivery of 12(S)-HETE to the airways of mice significantly attenuated the development of allergic airways inflammation and the production of IL-5 and IL-13. In summary, our results suggest that production of Ym1/2 in response to IL-13 promotes Th2 cytokine production and allergic airways inflammation by inhibiting the production of 12(S)-HETE by 12/15-LOX.


Assuntos
Quitinases/fisiologia , Citocinas/biossíntese , Eosinofilia/prevenção & controle , Mediadores da Inflamação/fisiologia , Lectinas/fisiologia , Inibidores de Lipoxigenase , Transdução de Sinais/imunologia , Células Th2/imunologia , beta-N-Acetil-Hexosaminidases/fisiologia , Animais , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Células Cultivadas , Quitinases/biossíntese , Quitinases/genética , Técnicas de Cocultura , Citocinas/antagonistas & inibidores , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Eosinofilia/enzimologia , Eosinofilia/patologia , Interleucina-13/deficiência , Interleucina-13/genética , Interleucina-13/fisiologia , Lectinas/biossíntese , Lectinas/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Células Th2/enzimologia , Células Th2/patologia , beta-N-Acetil-Hexosaminidases/biossíntese , beta-N-Acetil-Hexosaminidases/genética
13.
Mol Cell Endocrinol ; 301(1-2): 251-8, 2009 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-18786604

RESUMO

17beta-Hydroxysteroid dehydrogenases (17beta-HSDs) are responsible for the pre-receptor reduction/oxidation of steroids at the 17-position into active/inactive hormones, and the 15 known enzymes vary in their substrate specificity, localisation, and directional activity. 17beta-HSD Type 3 (17beta-HSD3) has been seen to be over-expressed in prostate cancer, and catalyses the reduction of androstenedione (Adione) to testosterone (T), which stimulates prostate tumour growth. Specific inhibitors of 17beta-HSD3 may have a role in the treatment of hormone-dependent prostate cancer and benign prostate hyperplasia, and also have potential as male anti-fertility agents. A 293-EBNA-based cell line with stable expression of transfected human 17beta-HSD3 was created and used to develop a whole cell radiometric TLC-based assay to assess the 17beta-HSD3 inhibitory potency of a series of compounds. STX2171 and STX2624 (IC(50) values in the 200-450nM range) were two of several active inhibitors identified. In similar TLC-based assays these compounds were found to be inactive against 17beta-HSD1 and 17beta-HSD2, indicating selectivity. A novel proof of concept model was developed to study the efficacy of the compounds in vitro using the androgen receptor positive hormone-dependent prostate cancer cell line, LNCaPwt, and its derivative, LNCaP[17beta-HSD3], transfected and selected for stable expression of 17beta-HSD3. The proliferation of the parental cell line was most efficiently stimulated by 5alpha-dihydrotestosterone (DHT), but the LNCaP[17beta-HSD3] cells were equally stimulated by Adione, indicating that 17beta-HSD3 efficiently converts Adione to T in this model. Adione-stimulated proliferation of LNCaP[17beta-HSD3] cells was inhibited in the presence of either STX2171 or STX2624. The compounds alone neither stimulated proliferation of the cells nor caused significant cell death, indicating that they are non-androgenic with low cytotoxicity. STX2171 inhibited Adione-stimulated growth of xenografts established from LNCaPwt cells in castrated mice in vivo. In conclusion, a primary screening assay and proof of concept model have been developed to study the efficacy of 17beta-HSD3 inhibitory compounds, which may have a role in the treatment of hormone-dependent cancer. Active compounds are selective for 17beta-HSD3 over 17beta-HSD1 and 17beta-HSD2, non-androgenic with low toxicity, and efficacious in both an in vitro proof of concept model and in an in vivo tumour model.


Assuntos
17-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/análise , Inibidores Enzimáticos/farmacologia , Hormônios/farmacologia , Neoplasias da Próstata/enzimologia , 17-Hidroxiesteroide Desidrogenases/classificação , Animais , Antineoplásicos/análise , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Inibidores Enzimáticos/química , Humanos , Masculino , Camundongos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Curr Drug Targets ; 9(6): 485-94, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18537587

RESUMO

Ovalbumin challenge models of asthma offer many opportunities for increasing our understanding of the pathogenetic mechanisms underlying this disease, as well as for identifying novel therapeutic targets. There is no single "classical" model, because numerous alternatives exist with respect to the choice of mouse strain, method of sensitisation, route and duration of challenge, and approach to assessing the host response. Moreover, the limitations of these models need to be recognised when attempting to interpret experimental findings. Nevertheless, careful use of well-defined models allows investigators to answer specific questions that are otherwise difficult to address.


Assuntos
Asma/imunologia , Modelos Animais de Doenças , Animais , Asma/patologia , Asma/terapia , Avaliação Pré-Clínica de Medicamentos , Humanos , Imunização/métodos , Camundongos , Camundongos Endogâmicos , Ovalbumina/imunologia , Hipersensibilidade Respiratória/fisiopatologia
15.
Cogn Neuropsychiatry ; 12(5): 422-36, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17691000

RESUMO

The thalamus has been described as a "relay station" for sensory information from most sensory modalities projecting to cortical areas. Therefore injury to the thalamus may result in multimodal sensory and motor deficits. In the present study, a 61-year-old woman suffered a right thalamic cerebral vascular accident (CVA; as evidenced by a computerised tomography [CT] scan). Secondary to this incident, she complained of altered sensations across multiple sensory modalities, including olfactory, visual, auditory, tactile, temperature, and pain sensation. Interestingly, during recovery from the thalamic CVA, the patient reported hallucinations in all the modalities cited above. Multimodal dysaethesias (odd sensations) and hallucinations showed reliable laterality in the affective valence across modalities with positive associations within right hemispace and negative associations within left hemispace. Overall, the results support multimodal role of the thalamus and provide evidence for lateralisation of positive and negative affect within the right and left hemispheres respectively.


Assuntos
Emoções/fisiologia , Lateralidade Funcional/fisiologia , Alucinações/etiologia , Alucinações/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Tálamo/fisiopatologia , Feminino , Alucinações/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tomografia Computadorizada por Raios X
16.
J Immunol ; 177(8): 5595-603, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17015747

RESUMO

Increased arginase I activity is associated with allergic disorders such as asthma. How arginase I contributes to and is regulated by allergic inflammatory processes remains unknown. CD4+ Th2 lymphocytes (Th2 cells) and IL-13 are two crucial immune regulators that use STAT6-dependent pathways to induce allergic airways inflammation and enhanced airways responsiveness to spasmogens (airways hyperresponsiveness (AHR)). This pathway is also used to activate arginase I in isolated cells and in hepatic infection with helminths. In the present study, we show that arginase I expression is also regulated in the lung in a STAT6-dependent manner by Th2-induced allergic inflammation or by IL-13 alone. IL-13-induced expression of arginase I correlated directly with increased synthesis of urea and with reduced synthesis of NO. Expression of arginase I, but not eosinophilia or mucus hypersecretion, temporally correlated with the development, persistence, and resolution of IL-13-induced AHR. Pharmacological supplementation with l-arginine or with NO donors amplified or attenuated IL-13-induced AHR, respectively. Moreover, inducing loss of function of arginase I specifically in the lung by using RNA interference abrogated the development of IL-13-induced AHR. These data suggest an important role for metabolism of l-arginine by arginase I in the modulation of IL-13-induced AHR and identify a potential pathway distal to cytokine receptor interactions for the control of IL-13-mediated bronchoconstriction in asthma.


Assuntos
Arginase/antagonistas & inibidores , Arginase/fisiologia , Hiper-Reatividade Brônquica/etiologia , Interleucina-13/fisiologia , Interferência de RNA , Animais , Arginase/genética , Arginase/metabolismo , Arginina/metabolismo , Asma/etiologia , Asma/metabolismo , Regulação Enzimológica da Expressão Gênica , Pulmão/enzimologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Doadores de Óxido Nítrico/metabolismo , Fator de Transcrição STAT6 , Células Th2
17.
Circulation ; 110(10): 1231-5, 2004 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-15337698

RESUMO

BACKGROUND: Ischemia/reperfusion (I/R) injury complicates myocardial infarction and stroke by exacerbating tissue damage and increasing risk of mortality. We have recently identified C-type natriuretic peptide (CNP) as an endothelium-derived hyperpolarizing factor in the mesenteric resistance vasculature and described a novel signaling pathway involving activation of natriuretic peptide receptor C (NPR-C), which plays a pivotal role in the regulation of local blood flow. We tested the hypothesis that CNP/NPR-C signaling is a novel regulatory pathway governing coronary blood flow and protecting against I/R injury. METHODS AND RESULTS: CNP and (Cys18)-atrial natriuretic factor (4-23) amide (cANF(4-23)) elicited dose-dependent decreases in coronary perfusion pressure (CPP) that were blocked by Ba(2+) and ouabain in the isolated Langendorff rat heart. The endothelium-dependent vasodilator acetylcholine elicited the release of CNP from the coronary endothelium. CNP and cANF(4-23) reduced infarct size after 25 minutes of global ischemia and 120 minutes of reperfusion, maintaining CPP and left ventricular pressure at preischemic values. The vasorelaxant and protective activity of CNP and cANF(4-23) were enhanced in the absence of endothelium-derived nitric oxide. CONCLUSIONS: Endothelium-derived CNP is involved in the regulation of the coronary circulation, and NPR-C activation underlies the vasorelaxant activity of this peptide. Moreover, this newly defined pathway represents a protective mechanism against I/R injury and a novel target for therapeutic intervention in ischemic cardiovascular disorders.


Assuntos
Circulação Coronária/efeitos dos fármacos , Peptídeo Natriurético Tipo C/fisiologia , Receptores do Fator Natriurético Atrial/fisiologia , Acetilcolina/farmacologia , Animais , Fator Natriurético Atrial/farmacologia , Fator Natriurético Atrial/uso terapêutico , Bário/farmacologia , Avaliação Pré-Clínica de Medicamentos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Masculino , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , NG-Nitroarginina Metil Éster/farmacologia , Peptídeo Natriurético Tipo C/metabolismo , Peptídeo Natriurético Tipo C/farmacologia , Peptídeo Natriurético Tipo C/uso terapêutico , Óxido Nítrico/fisiologia , Ouabaína/farmacologia , Fragmentos de Peptídeos/farmacologia , Fragmentos de Peptídeos/uso terapêutico , Ratos , Ratos Wistar , Receptores do Fator Natriurético Atrial/efeitos dos fármacos , Transdução de Sinais , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Vasodilatadores/uso terapêutico
18.
Appl Psychophysiol Biofeedback ; 29(2): 141-7, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15208977

RESUMO

Biofeedback and nocturnal alarms using electromyographic (EMG) activity of the masseter muscles have often been used to treat nocturnal bruxism. However, although use of EMG activated nocturnal alarms has been successful, the clinical utility of the devices reported in the literature to date is questionable. For instance, many of the devices are cumbersome and specifically designed and constructed by the investigators. Hence, the purpose of the present investigation was to test the clinical utility of the Calmset (Thought Technology Limited, Montreal, Canada), a commercially available, user-friendly, compact, and portable EMG biofeedback instrument that may be used as an EMG activated nocturnal alarm. To meet this objective, the Calmset was used both to facilitate assessment and to treat an individual with chronic nocturnal bruxism. The results indicated that the patient exhibited fewer bruxing episodes following treatment and that treatment gains were maintained 6 months following termination of treatment. Advantages and disadvantages of using the Calmset are discussed.


Assuntos
Biorretroalimentação Psicológica , Terapia de Relaxamento , Bruxismo do Sono/terapia , Adulto , Doença Crônica , Eletromiografia , Humanos , Masculino , Fatores de Tempo , Resultado do Tratamento
19.
Acta Ophthalmol Scand ; 81(2): 118-22, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12752048

RESUMO

PURPOSE: To compare the subjective visual experiences of patients during phacoemulsification and intraocular lens (IOL) implantation using regional and topical anaesthesia. DESIGN: A prospective, cohort, questionnaire-based study. METHODS: The study cohort consisted of 247 patients without pre-existing ocular pathology who underwent routine phacoemulsification and IOL implantation. The mean age of the subjects was 75.4 +/- 9.4 years and 34.5% of them had a history of cataract surgery. Three different methods of local anaesthesia were used: 66 (26.7%) of the patients were given topical anaesthesia (TA); 74 (30.0%) were given sub-Tenon's anaesthesia (SA), and 107(43.3%) were given peribulbar anaesthesia (PA). The patients were interviewed immediately after surgery by theatre staff using a standardized questionnaire that investigated their intraoperative visual experiences. RESULTS: There was no significant difference between the three methods of anaesthesia regarding light perception during the surgery. However, patients undergoing surgery under TA experienced brighter light intensity levels (78.3%) than those given SA (50.0%) and PA (55.7%) (p = 0.02). A total of 69.6% of subjects who received TA reported visual perception of colours during surgery, as opposed to 56.8% of SA recipients and 49.0% of PA recipients (p = 0.02). In addition, patients under TA were more aware of surgical instruments (26.1%) than those under SA (10.8%) and PA (15.9%) (p = 0.08). The vast majority of patients in all three groups found the visual experience to be non-frightening. There were no associations between intraoperative visual impression and age or sex. Although not statistically significant (p = 0.06), prior cataract surgery appeared to alleviate some of the anxiety associated with the visual experience. CONCLUSION: Patients undergoing regional and topical anaesthesia experience a wide variety of visual sensations during surgery. The differences in visual impressions between the groups may reflect the varying degrees of optic nerve blockade that result from the different anaesthetics.


Assuntos
Anestesia por Condução , Anestesia Local , Extração de Catarata , Facoemulsificação , Visão Ocular , Idoso , Idoso de 80 Anos ou mais , Ansiedade/etiologia , Ansiedade/psicologia , Extração de Catarata/psicologia , Estudos de Coortes , Percepção de Cores , Feminino , Humanos , Período Intraoperatório , Lentes Intraoculares , Luz , Masculino , Pessoa de Meia-Idade , Facoemulsificação/psicologia , Estudos Prospectivos , Reoperação , Inquéritos e Questionários
20.
Am J Respir Cell Mol Biol ; 27(3): 286-96, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12204890

RESUMO

Zn may have an important protective role in the respiratory epithelium and Zn deficiency may enhance airway inflammation and epithelial damage. The effects of mild nutritional Zn deficiency on airway hyperresponsiveness (AHR) and airway inflammation in mice sensitized and challenged with ovalbumin (OVA) to induce an allergic response were investigated. Balb/c mice were given Zn normal (ZN, 50 mg/kg Zn) or Zn limited diets (ZL, 14 mg/kg Zn) before and during induction of allergic airway inflammation, with appropriate controls (saline-treated, SAL). ZL mice had greater levels of AHR than ZN mice, regardless of presence or absence of allergic inflammation. These mice also had increased eosinophilia and mucus cell hyperplasia compared with ZN mice. Second, ZN and ZL OVA-treated mice had significant decreases in airway epithelial Zinquin fluorescence, indicating a lowered availability of Zn compared with their SAL-treated counterparts. In contrast, the pro-apoptotic protein caspase-3, which was co-localized with Zn in the apical epithelium, was significantly increased in both ZN and ZL OVA-treated mice. Immunologically active caspase-3 and apoptosis were increased in OVA-treated mice, especially the ZL group. These findings provide the first data for adverse effects of Zn deficiency on the respiratory epithelium and support a role for altered Zn homeostasis and caspase upregulation in asthma.


Assuntos
Caspases/metabolismo , Homeostase , Inflamação/metabolismo , Hipersensibilidade Respiratória/metabolismo , Hipersensibilidade Respiratória/fisiopatologia , Zinco/metabolismo , Animais , Apoptose , Peso Corporal/efeitos dos fármacos , Caspase 3 , Suplementos Nutricionais , Modelos Animais de Doenças , Precursores Enzimáticos/metabolismo , Eosinofilia/induzido quimicamente , Eosinofilia/metabolismo , Eosinofilia/patologia , Células Epiteliais/metabolismo , Feminino , Inflamação/fisiopatologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/toxicidade , Mucosa Respiratória/patologia , Zinco/farmacologia
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