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1.
Nutr Res Rev ; 34(2): 222-239, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33280615

RESUMO

There is increasing evidence for the health benefits of dietary nitrates including lowering blood pressure and enhancing cardiovascular health. Although commensal oral bacteria play an important role in converting dietary nitrate to nitrite, very little is known about the potential role of these bacteria in blood pressure regulation and maintenance of vascular tone. The main purpose of this review is to present the current evidence on the involvement of the oral microbiome in mediating the beneficial effects of dietary nitrate on vascular function and to identify sources of inter-individual differences in bacterial composition. A systematic approach was used to identify the relevant articles published on PubMed and Web of Science in English from January 1950 until September 2019 examining the effects of dietary nitrate on oral microbiome composition and association with blood pressure and vascular tone. To date, only a limited number of studies have been conducted, with nine in human subjects and three in animals focusing mainly on blood pressure. In general, elimination of oral bacteria with use of a chlorhexidine-based antiseptic mouthwash reduced the conversion of nitrate to nitrite and was accompanied in some studies by an increase in blood pressure in normotensive subjects. In conclusion, our findings suggest that oral bacteria may play an important role in mediating the beneficial effects of nitrate-rich foods on blood pressure. Further human intervention studies assessing the potential effects of dietary nitrate on oral bacteria composition and relationship to real-time measures of vascular function are needed, particularly in individuals with hypertension and those at risk of developing CVD.


Assuntos
Microbiota , Nitratos , Animais , Pressão Sanguínea , Humanos , Antissépticos Bucais , Óxido Nítrico , Nitritos
2.
Eur J Nutr ; 59(3): 895-908, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30927064

RESUMO

PURPOSE: Previously, the nutritional contribution, environmental and financial costs of dairy products have been examined independently. Our aim was to determine the nutritional adequacy, financial cost and environmental impact of UK diets according to dairy content. METHODS: In this cross-sectional study of adults (19-64 years) from the UK National Diet and Nutrition Survey years 1-4 (n = 1655), dietary intakes assessed from 4-day estimated food diaries were organized into quartiles (Q) total grams of dairy (milk, cheese, yogurt, dairy desserts) and analyzed using ANCOVA controlling for age, sex and energy intake with Bonferroni post hoc test for nutritional adequacy, Alternative Healthy Eating Index (AHEI-2010), environmental impact [greenhouse gas emissions (GHGE), eutrophication and acidification potentials], financial cost, markers of health and cardio-metabolic diseases. RESULTS: Nutritional adequacy, particularly for protein, calcium and iodine (+ 18 g, + 533 mg, + 95 g, respectively, all P < 0.0001) and AHEI-2010 (P < 0.0001) were significantly higher and systolic BP (- 2 mmHg, P = 0.019) was significantly lower for the higher-dairy diets (Q4, 274-1429 g/day dairy), compared with diets containing lower dairy (Q1, 0-96 g/day dairy). Diets in Q4 had lower financial cost (- 19%, P < 0.0001) and the greatest eutrophication potential, compared with Q1 (+ 29%, P < 0.0001). Yet the environmental (GHGE) and financial costs per unit nutrient (riboflavin, zinc, iodine, magnesium, calcium, potassium) were lower in Q4 than Q1 (all P < 0.0001). CONCLUSION: Diets with the highest dairy content had higher nutrient composition, better diet quality, were associated with lower BP and financial cost, but with higher eutrophication potential. Robust environmental data for many of food groups are limited and this needs an urgent addressing. TRIAL REGISTRATION: This trial was registered on clinicaltrials.gov as NCT03407248.


Assuntos
Laticínios/economia , Laticínios/estatística & dados numéricos , Dieta/economia , Dieta/métodos , Ingestão de Energia , Eutrofização , Adulto , Estudos Transversais , Registros de Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais/métodos , Inquéritos Nutricionais/estatística & dados numéricos , Reino Unido , Adulto Jovem
3.
Eur J Nutr ; 58(1): 409-422, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29330662

RESUMO

PURPOSE: Yogurt consumption has been associated with higher nutrient intakes, better diet quality and improved metabolic profiles in adults. Few studies have investigated these associations in children. This study investigated the association of yogurt consumption with nutrient intakes, diet quality and metabolic profile in British children. METHODS: Data from  1687 children aged 4-10 and 11-18 years of the National Diet and Nutrition Survey (NDNS) years 1-4 were analysed. Yogurt consumption was determined using a 4-day diet diary. Diet quality was assessed by the Healthy Eating Index 2010 (HEI-2010). Anthropometric measures, blood pressure, pulse pressure, plasma glucose, HbA1c, C-reactive protein, triacylglycerol, total cholesterol, high-and low-density cholesterol from NDNS were used. RESULTS: The highest tertile of yogurt consumption (T3) was associated with higher nutrient intakes, particularly for calcium (children 4-10 years: P < 0.0001; children 11-18 years P = 0.001), iodine (both age groups P < 0.0001) and riboflavin (both age groups P < 0.0001), and HEI-2010 score (both age groups P < 0.0001) in children aged 4-10 years (mean ± SD: 98.4 ± 35.7 g yogurt/day) and 11-18 years (mean ± SD: 105.4 ± 37.5 g yogurt/day) compared with non-consumers (0 g yogurt/d). Yogurt consumption was associated with significantly lower pulse pressure in children aged 4-10 years and lower HbA1c concentration, being shorter and having a larger hip circumference in children aged 11-18 years, compared with non-yogurt consumers. CONCLUSION: This study suggests that British children who are yogurt consumers (> 60 g/day) have higher overall diet quality, nutrient intakes and adequacy, lower pulse pressure (children aged 4-10 years) and HbA1c concentrations (children aged 11-18 years), were shorter and had a smaller hip circumference (children aged 11-18 years).


Assuntos
Dieta/métodos , Ingestão de Energia , Metaboloma , Inquéritos Nutricionais/estatística & dados numéricos , Iogurte , Adolescente , Glicemia/metabolismo , Proteína C-Reativa/metabolismo , Criança , Pré-Escolar , Estudos Transversais , Dieta/normas , Registros de Dieta , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Lipídeos/sangue , Masculino , Inquéritos Nutricionais/métodos , Reino Unido
4.
Nature ; 431(7012): 1087-91, 2004 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-15510146

RESUMO

Excavations at Liang Bua, a large limestone cave on the island of Flores in eastern Indonesia, have yielded evidence for a population of tiny hominins, sufficiently distinct anatomically to be assigned to a new species, Homo floresiensis. The finds comprise the cranial and some post-cranial remains of one individual, as well as a premolar from another individual in older deposits. Here we describe their context, implications and the remaining archaeological uncertainties. Dating by radiocarbon (14C), luminescence, uranium-series and electron spin resonance (ESR) methods indicates that H. floresiensis existed from before 38,000 years ago (kyr) until at least 18 kyr. Associated deposits contain stone artefacts and animal remains, including Komodo dragon and an endemic, dwarfed species of Stegodon. H. floresiensis originated from an early dispersal of Homo erectus (including specimens referred to as Homo ergaster and Homo georgicus) that reached Flores, and then survived on this island refuge until relatively recently. It overlapped significantly in time with Homo sapiens in the region, but we do not know if or how the two species interacted.


Assuntos
Arqueologia , Biodiversidade , Hominidae , Animais , Evolução Biológica , Constituição Corporal , Radioisótopos de Carbono , Feminino , Geografia , História Antiga , Hominidae/classificação , Atividades Humanas/história , Humanos , Indonésia , Comportamento Predatório , Reprodutibilidade dos Testes , Esqueleto , Crânio , Fatores de Tempo , Dente
5.
J Hum Evol ; 57(5): 437-49, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19733385

RESUMO

Excavations at Liang Bua, Flores, Indonesia, have yielded evidence for an endemic human species, Homo floresiensis, a population that occupied the cave between approximately 95-17ka. This discovery has major implications for early hominin evolution and dispersal in Africa and Asia, attracting worldwide interest. This preface describes the rationale for the excavations in historical, geographical, and wider research contexts, as well as the methods used. It also introduces the other papers on aspects of Liang Bua research that feature in this edition of the Journal of Human Evolution.


Assuntos
Evolução Biológica , Fósseis , Fenômenos Geológicos , Animais , Arqueologia , História Antiga , Hominidae/anatomia & histologia , Hominidae/classificação , Hominidae/genética , Humanos , Indonésia , Pesquisa
6.
J Hum Evol ; 57(5): 465-83, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19269678

RESUMO

Liang Bua, in Flores, Indonesia, was formed as a subterranean chamber over 600ka. From this time to the present, a series of geomorphic events influenced the structure of the cave and cave deposits, creating a complex stratigraphy. Within these deposits, nine main sedimentary units have been identified. The stratigraphic relationships between these units provide the evidence needed to reconstruct the geomorphic history of the cave. This history was dominated by water action, including slope wash processes, channel formation, pooling of water, and flowstone precipitation, which created waterfalls, cut-and-fill stratigraphy, large pools of water, and extensive flowstone cappings. The reconstructed sequence of events over the last 190k.yr. has been summarized by a series of time slices that demonstrate the nature of the occupational environment in Liang Bua. The earliest artifacts at the site, dated to approximately 190ka, testify to hominin presence in the area, but the reconstructions suggest that occupation of the cave itself may not have been possible until after approximately 100ka. At approximately 95ka, channel erosion of a basal unit, which displays evidence of deposition in a pond environment, created a greater relief on the cave floor, and formed remanent areas of higher ground that later became a focus for hominin occupation from 74-61ka by the west wall and in the center of the cave, and from approximately 18-17ka by the east wall. These zones have been identified according to the sloping nature of the stratigraphy and the distribution of artifacts, and their locations have implications for the archaeological interpretation of the site.


Assuntos
Fenômenos Geológicos , Animais , Arqueologia , Evolução Biológica , Geografia , Hominidae/classificação , Hominidae/genética , Humanos , Indonésia
7.
Clin Nephrol ; 72(5): 410-3, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19863887

RESUMO

Sarcoidosis is a multisystem disease of unknown etiology primarily affecting the lungs, skin, and lymph nodes. The disease usually manifests in young adults and is uncommon in childhood. Renal involvement, including granulomatous interstitial nephritis (GIN), is rare, and few cases of isolated sarcoid GIN have been reported in pediatrics. We report a case and review the literature.


Assuntos
Granuloma/diagnóstico , Nefrite Intersticial/diagnóstico , Sarcoidose/diagnóstico , Adolescente , Humanos , Hipertensão Renal/etiologia , Masculino , Nefrite Intersticial/complicações , Sarcoidose/complicações
9.
J Biomed Mater Res B Appl Biomater ; 83(2): 505-11, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17471514

RESUMO

UNLABELLED: Monosodium titanate (MST) particles effectively bind specific metals and are therefore promising compounds for delivery or sequestration of metals in biological contexts. Yet, the biological properties of MST are largely unexplored. Our previous study showed that the cytotoxicity of these compounds was mild, but the nature of the dose response curves suggested that residual titanates in culture may have interfered with the assay. In the current study, we assessed the importance of these artifacts, and extended our previous results using fibroblasts for biological evaluation. We also assessed the biological response to a new type of titanate (referred to as amorphous peroxo-titanate or APT) that shows more promising metal binding properties than MST. METHODS: The degree of titanate-induced interference in the MTT (mitochondrial activity assay) was estimated by means of cell-free assays with and without a final centrifugation step to remove residual titanate particulate. Cytotoxic responses to titanates were assessed by measuring succinate dehydrogenase activity (by MTT) in THP1 monocytes or L929 fibroblasts after 24-72 h exposures. Monocytic activation by APT was assessed by TNFalpha secretion (ELISA) from monocytes with or without lipopolysaccharide (LPS) activation. RESULTS: We confirmed that residual titanate particulates may alter the SDH activity assay, but that this effect is eliminated by adding a final centrifugation step to the standard MTT procedure. Addition of MST or APT at concentrations up to 100 mg/L altered succinate dehydrogenase activity by < 25% in both monocytes and fibroblasts. Fibroblasts displayed time-dependent adaptation to the MST. APT did not trigger TNFalpha secretion or modulate LPS-induced TNFalpha secretion from monocytes. CONCLUSIONS: Although further in vitro and in vivo assessment is needed, MST and APT exhibit biological properties that are promising for their use as agents to sequester or deliver metals in biological systems.


Assuntos
Materiais Biocompatíveis/toxicidade , Fibroblastos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Óxidos/toxicidade , Titânio/toxicidade , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Fibroblastos/enzimologia , Humanos , Teste de Materiais , Camundongos , Mitocôndrias/efeitos dos fármacos , Monócitos/imunologia , Óxidos/química , Succinato Desidrogenase/análise , Titânio/química , Fator de Necrose Tumoral alfa/análise
10.
J Biomed Mater Res B Appl Biomater ; 78(2): 296-301, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16362965

RESUMO

Monosodium titanate (MST) is an inorganic sorbent/ion exchanger developed for the removal of radionuclides from nuclear wastes. We investigated the ability of MST to bind Cd(II), Hg(II), Au(III), or the Au-organic compound auranofin to establish the utility of MST for applications in environmental decontamination or medical therapy (drug delivery). Adsorption isotherms for MST were determined at pH 7-7.5 in water or phosphate-buffered saline. The extent of metal binding was determined spectroscopically by measuring the concentrations of the metals in solution before and after contact with the MST. Cytotoxic responses to MST were assessed using THP1 monocytes and succinate dehydrogenase activity. Monocytic activation by MST was assessed by TNFalpha secretion (ELISA) with or without lipopolysaccharide (LPS) activation. MST adsorbed Cd(II), Hg(II), and Au(III) under conditions similar to those in physiological systems. MST exhibited the highest affinity for Cd(II) followed by Hg(II) and Au (III). MST (up to 100 mg/L) exhibited only minor (<25% suppression of succinate dehydrogenase) cytotoxicity and did not trigger TNFalpha secretion nor modulate LPS-induced TNFalpha secretion from monocytes. MST exhibits high affinity for biometals with no significant biological liabilities in these introductory studies. MST deserves further scrutiny as a substance with the capacity to decontaminate biological environments or deliver metals or metal compounds for therapeutic applications.


Assuntos
Auranofina/química , Sistemas de Liberação de Medicamentos , Metais Pesados/química , Monócitos , Adsorção , Auranofina/uso terapêutico , Materiais Biocompatíveis , Linhagem Celular , Descontaminação , Humanos , Troca Iônica , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/toxicidade , Teste de Materiais , Metais Pesados/uso terapêutico , Monócitos/metabolismo , Monócitos/ultraestrutura , Resíduos Radioativos , Succinato Desidrogenase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Biochim Biophys Acta ; 1018(1): 47-54, 1990 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-2165419

RESUMO

Resonance Raman spectra of bc1 complexes from Rhodospirillum rubrum have been obtained. Various resonance conditions and the stoichiometric redox titration of the complex were used to isolate and identify the contributions of the heme c1 and heme b active sites to the observed spectra. The complex was found to partially photoreduce when exposed to laser excitation.


Assuntos
Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Rhodospirillum rubrum/análise , Análise Espectral Raman , Ácido Ascórbico/farmacologia , Ditionita/farmacologia , Eletroquímica , Transporte de Elétrons , Ferricianetos/farmacologia , Heme/metabolismo , Oxirredução , Fotoquímica , Espectrofotometria
12.
Clin Pharmacol Ther ; 23(2): 241-6, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-620486

RESUMO

An assay for polythiazide, sufficiently sensitive to measure plasma concentrations of this high-potency diuretic agent, has been developed. The assay is based on acid hydrolysis to trifluoroethylthioacetaldehyde and electron-capture gas chromatography. Sensitivity down to 0.2 ng/ml was achieved. In a study in normal human subjects receiving single 1-mg oral doses of polythiazide, the mean plasma half-lives for absorption and elimination were 1.2 and 25.7 hr, respectively. The latter is consistent with the extended duration of action of polythiazide. Approximately 25% of the drug was excreted unchanged in the urine.


Assuntos
Politiazida/metabolismo , Adolescente , Adulto , Cromatografia Gasosa/métodos , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Politiazida/sangue , Politiazida/urina
13.
Clin Pharmacol Ther ; 18(4): 441-8, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-809225

RESUMO

In rats, both the plasma concentrations and the anti-inflammatory activity of sudoxicam are depressed by concurrent administration of aspirin, being similar to that reported for other nonsteroidal agents, whereas, in man and monkey, plasma concentrations of sudoxicam are not affected by concurrent administration of aspirin. In this respect sudoxicam differs from such other nonsteroidal anti-inflammatory agents as indomethacin and naproxen.


Assuntos
Aspirina/farmacologia , Tiazinas/farmacologia , Animais , Artrite Reumatoide/tratamento farmacológico , Depressão Química , Interações Medicamentosas , Edema/tratamento farmacológico , Meia-Vida , Haplorrinos , Humanos , Cinética , Macaca mulatta , Masculino , Ratos , Especificidade da Espécie , Tiazinas/sangue , Tiazinas/uso terapêutico
14.
Clin Pharmacol Ther ; 27(6): 779-83, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7379445

RESUMO

Single and repeated doses of prazosin were given to 17 hypertensive patients, 5 with normal renal function and 12 with impaired renal function. Blood for prazosin assay was drawn after a 1-mg single dose and after patients reached steady-state levels with their long-term maintenance dose. As blood was drawn blood pressure was recorded. Prazosin absorption was not altered in patients with impaired renal function, and there is no cumulation of the drug when given repeatedly to patients with impaired renal function. Elimination kinetics were virtually identical regardless of degree of renal function. Effect on blood pressure was significantly better at the dosage range of 3 to 8 mg/day than at higher doses of 9 to 20 mg/day. There does not appear to be a direct relationship between the peak plasma prazosin level and the nadir of antihypertensive response. This would seem to indicate that the drug leaves the plasma and goes to the vascular smooth muscle receptor site of action. There appears to be no impairment in prazosin elimination in patients with impaired renal function, and its effectiveness (with diuretic or dialysis) is optimum at 3 to 8 mg/day.


Assuntos
Hipertensão/tratamento farmacológico , Falência Renal Crônica/metabolismo , Prazosina/metabolismo , Quinazolinas/metabolismo , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Proteínas Sanguíneas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Prazosina/sangue , Prazosina/farmacologia , Ligação Proteica , Fatores de Tempo
15.
FEBS Lett ; 452(3): 145-9, 1999 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-10386579

RESUMO

Triacylglycerols are the most important storage lipids in most plants and animals. Acyl-CoA:diacylglycerol acyltransferase (EC 2.3.1.20) catalyzes the final step of the pathway of triacylglycerol synthesis and is the only step which is unique to this process. Diacylglycerol acyltransferase is required for the synthesis of storage oil in a wide range of oil-bearing seeds and fruits and in floral structures such as petals, anthers and pollen. We describe the first cloning and functional expression of a cDNA encoding diacylglycerol acyltransferase from a plant. The cDNA, cloned from Arabidopsis thaliana, encodes a 520 amino acid protein with a predicted molecular mass of 59.0 kDa which shares 38% amino acid sequence identity with diacylglycerol acyltransferase from mouse. When expressed in insect cell cultures, the protein catalyzes the synthesis of [14C]triacylglycerol from [14C]diacylglycerol and acyl-CoA. Primer extension analysis revealed that the transcription begins 225 bases before the translation start site, yielding an unusually long 5' untranslated region. The gene is expressed in a wide range of tissues but most strongly in developing embryos and petals of flowers.


Assuntos
Aciltransferases/genética , Aciltransferases/metabolismo , Arabidopsis/enzimologia , Aciltransferases/química , Sequência de Aminoácidos , Animais , Arabidopsis/genética , Sequência de Bases , Clonagem Molecular , DNA Complementar , Bases de Dados como Assunto , Diacilglicerol O-Aciltransferase , Camundongos , Dados de Sequência Molecular , Peso Molecular , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Gênica
16.
Am J Med ; 81(5B): 22-8, 1986 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-3538867

RESUMO

A large body of data is available regarding the relationship between demographic factors, particularly age, sex, and disease state, and the pharmacokinetics of piroxicam. Of additional interest is the relationship between piroxicam pharmacokinetics (particularly steady-state plasma levels) and adverse effects. Studies with piroxicam that are reviewed herein include studies on kinetics in renal impairment, single-dose studies, multiple-dose studies, and therapeutic drug monitoring studies. Although results were not always consistent, some studies suggested that plasma levels of piroxicam tend to be increased in elderly female patients. However, the increases were small and did not correlate with adverse events. These data suggest that there is no correlation between piroxicam plasma concentrations and adverse events.


Assuntos
Piroxicam/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/metabolismo , Ensaios Clínicos como Assunto , Feminino , Meia-Vida , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Piroxicam/efeitos adversos , Piroxicam/sangue , Fatores Sexuais
17.
J Med Chem ; 29(8): 1384-9, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3016263

RESUMO

Several "sugar" modified acyclic nucleoside analogues related to 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine (DHPG, 2) were synthesized and evaluated for antiviral activity. The preparation generally involved the condensation of the acetoxymethyl ether of alcohols 6c-g and 10-12a with diacetylguanine to give adducts 7c-g and 14-16, which were then deprotected to afford analogues 9c-g and 17-19. Alternatively, alcohols 12a and 13a were converted to iodides via their tosylates 12b and 13b and then reacted with the sodium salt of guanine to afford, after deprotection, analogues 22 and 23. A crossed aldol-Cannizzaro reaction on aldehyde 27 readily afforded 28, which was deprotected to give analogue 29. An in vitro assay against HSV-1 showed that all compounds tested were less active than DHPG, though several were good substrates for the viral thymidine kinase. The more promising acyclic nucleosides 9c, 19, and 29 were evaluated in a mouse encephalitis model and proved ineffective at preventing death at a dose of 20 mg/kg.


Assuntos
Aciclovir/análogos & derivados , Antivirais/síntese química , Desoxiguanosina/análogos & derivados , Ganciclovir/análogos & derivados , Simplexvirus/efeitos dos fármacos , Aciclovir/síntese química , Aciclovir/farmacologia , Animais , Antivirais/farmacologia , Desoxiguanosina/síntese química , Desoxiguanosina/farmacologia , Feminino , Isomerismo , Camundongos , Timidina Quinase/metabolismo
18.
J Med Chem ; 35(21): 3919-27, 1992 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-1331449

RESUMO

The first nonpeptide antagonists of the neurohypophyseal hormone, oxytocin (OT) are described. Derivatives of the spiroindenepiperidine ring system, these compounds include L-366,509, an orally bioavailable OT antagonist with good in vivo duration. The potential use of these agents for treatment of preterm labor and their significance as new nonpeptide ligands for peptide receptors are discussed.


Assuntos
Ocitocina/antagonistas & inibidores , Piperidinas/farmacologia , Compostos de Espiro/farmacologia , Administração Oral , Animais , Disponibilidade Biológica , Feminino , Espectroscopia de Ressonância Magnética , Trabalho de Parto Prematuro/tratamento farmacológico , Piperidinas/administração & dosagem , Piperidinas/uso terapêutico , Gravidez , Ratos , Receptores de Angiotensina/metabolismo , Receptores de Ocitocina , Receptores de Vasopressinas/metabolismo , Compostos de Espiro/administração & dosagem , Compostos de Espiro/uso terapêutico , Relação Estrutura-Atividade
19.
J Med Chem ; 41(12): 2146-63, 1998 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-9622556

RESUMO

The previously reported oxytocin antagonist L-371,257 (2) has been modified at its acetylpiperidine terminus to incorporate various pyridine N-oxide groups. This modification has led to the identification of compounds with improved pharmacokinetics and excellent oral bioavailability. The pyridine N-oxide series is exemplified by L-372,662 (30), which possessed good potency in vitro (Ki = 4.1 nM, cloned human oxytocin receptor) and in vivo (intravenous AD50 = 0.71 mg/kg in the rat), excellent oral bioavailability (90% in the rat, 96% in the dog), good aqueous solubility (>8.5 mg/mL at pH 5.2) which should facilitate formulation for iv administration, and excellent selectivity against the human arginine vasopressin receptors. Incorporation of a 5-fluoro substituent on the central benzoyl ring of this class of oxytocin antagonists enhanced in vitro and in vivo potency but was detrimental to the pharmacokinetic profiles of these compounds. Although lipophilic substitution around the pyridine ring of compound 30 gave higher affinity in vitro, such substituents were a metabolic liability and caused shortfalls in vivo. Two approaches to prevent this metabolism, addition of a cyclic constraint and incorporation of trifluoromethyl groups, were examined. The former approach was ineffective because of metabolic hydroxylation on the constrained ring system, whereas the latter showed improvement in plasma pharmacokinetics in some cases.


Assuntos
Oxazinas , Piridinas , Receptores de Ocitocina/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Cães , Feminino , Humanos , Rim/citologia , Rim/embriologia , Rim/metabolismo , Fígado/metabolismo , Masculino , Espectrometria de Massas , Oxazinas/síntese química , Oxazinas/metabolismo , Oxazinas/farmacocinética , Oxazinas/farmacologia , Gravidez , Piridinas/síntese química , Piridinas/metabolismo , Piridinas/farmacocinética , Piridinas/farmacologia , Ratos , Receptores de Ocitocina/metabolismo , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Espectrofotometria Ultravioleta , Contração Uterina/efeitos dos fármacos , Útero/efeitos dos fármacos , Útero/fisiologia
20.
Comb Chem High Throughput Screen ; 7(5): 495-510, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15320714

RESUMO

In recent years the trend in combinatorial library design has shifted to include target class focusing along with diversity and drug-likeness criteria. In this manuscript we review the computational tools available for target class library design and highlight the areas where they have proven useful in our work. The protein kinase family is used to illustrated structure-based target class focused library design, and the G-protein coupled receptor (GPCR) family is used to illustrate ligand-based target class focused library design. Most of the tools discussed are those designed for libraries targeted to a single protein and are simply applied "brute-force" to a large number of targets within the family. The tools that have proven to be the most useful in our work are those that can extract trends from the computational data such as docking and clustering or data mining large amounts of structure activity or high throughput screening data. Finally, areas where improvements are needed in the computational tools available for target class focusing are highlighted. These areas include tools to extract the relevant patterns from all available information for a family of targets, tools to efficiently apply models for all targets in the family rather than just a small subset, mining tools to extract the relevant information from the computational absorption, distribution, metabolism, excretion and toxicity (ADMET) and targeting data, and tools to allow interactive exploration of the virtual space around a library to facilitate the selection of the library that best suits the needs of the design team.


Assuntos
Desenho de Fármacos , Fosfotransferases/antagonistas & inibidores , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Animais , Biblioteca Genômica , Humanos , Ligantes , Modelos Moleculares , Conformação Molecular , Fosfotransferases/química , Fosfotransferases/genética , Inibidores de Proteínas Quinases , Proteínas Quinases/química , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Relação Estrutura-Atividade
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