Base de dados : MEDLINE Pesquisa : D03.132.960.651 [Categoria DeCS] Referências encontradas : 1527 [refinar] Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 153

ir para página

1 / 1527

MEDLINE

seleciona para imprimir Fotocópia Registro de Ensaios Clínicos Texto completo

[PMID]: 28003203 [Au] Autor: Sansone R; Ottaviani JI; Rodriguez-Mateos A; Heinen Y; Noske D; Spencer JP; Crozier A; Merx MW; Kelm M; Schroeter H; Heiss C [Ad] Endereço: Division of Cardiology, Pulmonology, and Vascular Medicine, Medical Faculty, University of Düsseldorf, Düsseldorf, Germany. [Ti] Título: Methylxanthines enhance the effects of cocoa flavanols on cardiovascular function: randomized, double-masked controlled studies. [So] Source: Am J Clin Nutr;105(2):352-360, 2017 Feb. [Is] ISSN: 1938-3207 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: BACKGROUND: Cocoa flavanol intake, especially that of (-)-epicatechin, has been linked to beneficial effects on human cardiovascular function. However, cocoa also contains the methylxanthines theobromine and caffeine, which may also affect vascular function. OBJECTIVE: We sought to determine whether an interaction between cocoa flavanols and methylxanthines exists that influences cocoa flavanol-dependent vascular effects. DESIGN: Test drinks that contained various amounts of cocoa flavanols (0-820 mg) and methylxanthines (0-220 mg), either together or individually, were consumed by healthy volunteers (n = 47) in 4 different clinical studies-3 with a randomized, double-masked crossover design and 1 with 4 parallel crossover studies. Vascular status was assessed by measuring flow-mediated vasodilation (FMD), brachial pulse wave velocity (bPWV), circulating angiogenic cells (CACs), and blood pressure before and 2 h after the ingestion of test drinks. RESULTS: Although cocoa flavanol intake increased FMD 2 h after intake, the consumption of cocoa flavanols with methylxanthines resulted in a greater enhancement of FMD. Methylxanthine intake alone did not result in statistically significant changes in FMD. Cocoa flavanol ingestion alone decreased bPWV and diastolic blood pressure and increased CACs. Each of these changes was more pronounced when cocoa flavanols and methylxanthines were ingested together. It is important to note that the area under the curve of the plasma concentration of (-)-epicatechin metabolites over time was higher after the co-ingestion of cocoa flavanols and methylxanthines than after the intake of cocoa flavanols alone. Similar results were obtained when pure (-)-epicatechin and the methylxanthines theobromine and caffeine were consumed together. CONCLUSION: A substantial interaction between cocoa flavanols and methylxanthines exists at the level of absorption, in which the methylxanthines mediate an increased plasma concentration of (-)-epicatechin metabolites that coincides with enhanced vascular effects commonly ascribed to cocoa flavanol intake. This trial was registered at clinicaltrials.gov as NCT02149238. [Mh] Termos MeSH primário: Cacau/química Sistema Cardiovascular/efeitos dos fármacos Flavonóis/administração & dosagem Polifenóis/administração & dosagem Xantinas/administração & dosagem [Mh] Termos MeSH secundário: Adulto Biomarcadores/sangue Pressão Sanguínea/efeitos dos fármacos Proteína C-Reativa/metabolismo Cafeína/administração & dosagem Catequina/sangue Catequina/urina Estudos Cross-Over Método Duplo-Cego Determinação de Ponto Final Seres Humanos Masculino Análise de Onda de Pulso Teobromina/administração & dosagem Rigidez Vascular/efeitos dos fármacos Vasodilatação/efeitos dos fármacos Adulto Jovem [Pt] Tipo de publicação: JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL [Nm] Nome de substância: 0 (Biomarkers); 0 (Flavonols); 0 (Polyphenols); 0 (Xanthines); 28109-92-4 (methylxanthine); 3G6A5W338E (Caffeine); 8R1V1STN48 (Catechin); 9007-41-4 (C-Reactive Protein); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1706 [Cu] Atualização por classe: 170627 [Lr] Data última revisão: 170627 [Sb] Subgrupo de revista: AIM; IM [Da] Data de entrada para processamento: 161223 [Cl] Clinical Trial: ClinicalTrial [St] Status: MEDLINE [do] DOI: 10.3945/ajcn.116.140046

2 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27761618 [Au] Autor: Ashengroph M [Ad] Endereço: Department of Biological Sciences, Faculty of Sciences, University of Kurdistan, Pasdaran Str., P. O. Box 416, Sanandaj, Iran. m.ashengroph@uok.ac.ir. [Ti] Título: Salinivibrio costicola GL6, a Novel Isolated Strain for Biotransformation of Caffeine to Theobromine Under Hypersaline Conditions. [So] Source: Curr Microbiol;74(1):34-41, 2017 Jan. [Is] ISSN: 1432-0991 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: The present study has been conducted towards isolation of moderately halophilic bacteria capable of transforming caffeine into theobromine. A total of 45 caffeine-degrading moderate halophiles were enriched from hypersaline lakes and examined for the biotransformation of caffeine to theobromine by thin-layer chromatography (TLC) and high-performance liquid chromatography analyses. Strain GL6, giving the highest yield of theobromine, was isolated from the Hoz Soltan Lake, 20 % w/v salinity, central Iran, and identified as Salinivibrio costicola based on morphological and biochemical features as well as its 16S rRNA gene sequence analysis (GeneBank Accession No. KT378066) and DNA-DNA relatedness. The biotransformation of caffeine with strain GL6 leads to the formation of two metabolites, identified as theobromine and paraxanthine, but the yield of paraxanthine was much lower. Further study on the production of theobromine from caffeine under resting cell experiment was carried out subsequently. The optimal yield of theobromine (56 %) was obtained after a 32-h incubation using 5 mM of caffeine and 15 g l (wet weight) of biomass in 0.1 M saline phosphate buffer (pH 7.0 and 10 % w/v NaCl) under agitation 180 rpm at 30 °C. The biotransformed theobromine was purified by preparative TLC and subjected to FTIR and mass spectroscopy for chemical identification. This is the first evidence for biotransformation of caffeine into theobromine by strains of the genus Salinivibrio. [Mh] Termos MeSH primário: Cafeína/metabolismo Lagos/microbiologia Cloreto de Sódio/metabolismo Teobromina/metabolismo Vibrionaceae/metabolismo [Mh] Termos MeSH secundário: Técnicas de Tipagem Bacteriana Biotransformação DNA Bacteriano/genética Lagos/química Filogenia RNA Ribossômico 16S/genética Cloreto de Sódio/análise Vibrionaceae/classificação Vibrionaceae/genética Vibrionaceae/isolamento & purificação [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (DNA, Bacterial); 0 (RNA, Ribosomal, 16S); 3G6A5W338E (Caffeine); 451W47IQ8X (Sodium Chloride); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1701 [Cu] Atualização por classe: 170926 [Lr] Data última revisão: 170926 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 161021 [St] Status: MEDLINE [do] DOI: 10.1007/s00284-016-1148-z

3 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27720901 [Au] Autor: Ruchel JB; Braun JB; Adefegha SA; Guedes Manzoni A; Abdalla FH; de Oliveira JS; Trelles K; Signor C; Lopes ST; da Silva CB; Castilhos LG; Rubin MA; Leal DB [Ad] Endereço: Programa de Pós Graduação em Ciências Biológicas: Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de SantaMaria, Santa Maria, RS 97105-900, Brazil. Electronic address: jbruchel@yahoo.com.br. [Ti] Título: Guarana (Paullinia cupana) ameliorates memory impairment and modulates acetylcholinesterase activity in Poloxamer-407-induced hyperlipidemia in rat brain. [So] Source: Physiol Behav;168:11-19, 2017 Jan 01. [Is] ISSN: 1873-507X [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Hyperlipidemia is a risk factor for the development of cognitive dysfunction and atherosclerosis. Natural compounds have recently received special attention in relation to the treatment of disease due to their low cost and wide margin of safety. Thus, the aim of this study was to determine the possible preventive effect of guarana powder (Paullinia cupana) on memory impairment and acetylcholinesterase (AChE) activity in the brain structures of rats with Poloxamer-407-induced hyperlipidemia. Adult male Wistar rats were pretreated with guarana (12.5, 25 and 50mg/kg/day) and caffeine (0.2mg/kg/day) by gavage for a period of 30days. Simvastatin (0.04mg/kg) was administered as a comparative standard. Acute hyperlipidemia was induced with intraperitoneal injections of 500mg/kg of Poloxamer-407. Memory tests and evaluations of anxiety were performed. The cortex, cerebellum, hippocampus, hypothalamus and striatum were separated to assess acetylcholinesterase activity. Our results revealed that guarana powder was able to reduce the levels of TC and LDL-C in a manner similar to simvastatin. Guarana powder also partially reduced the liver damage caused by hyperlipidemia. Guarana was able to prevent changes in the activity of AChE and improve memory impairment due to hyperlipidemia. Guarana powder may therefore be a source of promising phytochemicals that can be used as adjuvant therapy in the management of hyperlipidemia and cognitive disorders. [Mh] Termos MeSH primário: Acetilcolinesterase/metabolismo Encéfalo/enzimologia Cafeína/uso terapêutico Hiperlipidemias Poloxâmero/toxicidade Tensoativos/toxicidade Teobromina/uso terapêutico Teofilina/uso terapêutico [Mh] Termos MeSH secundário: Animais Glicemia Colesterol/sangue Hiperlipidemias/induzido quimicamente Hiperlipidemias/tratamento farmacológico Hiperlipidemias/patologia Masculino Aprendizagem em Labirinto/efeitos dos fármacos Paullinia/química Extratos Vegetais/uso terapêutico Ratos Ratos Wistar Recognição (Psicologia)/efeitos dos fármacos Estatísticas não Paramétricas [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Blood Glucose); 0 (Plant Extracts); 0 (Surface-Active Agents); 0 (guarana powder); 106392-12-5 (Poloxamer); 3G6A5W338E (Caffeine); 97C5T2UQ7J (Cholesterol); C137DTR5RG (Theophylline); EC 3.1.1.7 (Acetylcholinesterase); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1706 [Cu] Atualização por classe: 170626 [Lr] Data última revisão: 170626 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 161107 [St] Status: MEDLINE

4 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 25259737 [Au] Autor: White DJ; Camfield DA; Maggini S; Pipingas A; Silberstein R; Stough C; Scholey A [Ad] Endereço: a Centre for Human Psychopharmacology, Swinburne University , Melbourne , Australia. [Ti] Título: The effect of a single dose of multivitamin and mineral combinations with and without guaraná on functional brain activity during a continuous performance task. [So] Source: Nutr Neurosci;20(1):8-22, 2017 Jan. [Is] ISSN: 1476-8305 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: OBJECTIVES: Relatively few studies have explored the possibility of acute cognitive effects of multivitamin ingestion. This report explores the acute brain electrophysiological changes associated with multivitamin and mineral supplementation, with and without guaraná, using the steady-state visually evoked potential (SSVEP). METHODS: Based on the known SSVEP correlates of A-X continuous performance task (CPT) performance, and sensitivity to acute psychopharmacological manipulations, the A-X CPT was adopted as a task paradigm to explore treatment-related neurophysiological changes in attentional processing. Twenty healthy non-smoking adults aged 21-39 years (mean age = 28.35 years, SD = 5.52) took part in this double-blind, placebo-controlled, randomized, balanced crossover design study. RESULTS: The study demonstrated both transient and tonic changes in the SSVEP response during completion of the A-X CPT following multivitamin and mineral treatment both with and without guaraná. Transient changes in SSVEP response in prefrontal regions were observed after a single dose of a multivitamin and mineral preparation indicative of enhanced activity within brain regions engaged by the attentional demands of the task. This pattern of change in frontal regions was correlated with improved behavioural performance after treatment with the multivitamin and mineral combination. Where tonic shifts in SSVEP response were investigated, multivitamin and mineral treatment was associated with a pattern of increased inhibition across posterior regions, with enhanced excitatory processing in prefrontal regions. In contrast, multivitamin and mineral treatment with additional guaraná showed a tonic shift towards greater excitatory processes after a single treatment, consistent with the caffeine content of this treatment. DISCUSSION: While preliminary in nature, these findings suggest a single multivitamin/mineral dose is sufficient to impact on functional brain activity in task-related brain regions. [Mh] Termos MeSH primário: Encéfalo/fisiologia Cafeína/administração & dosagem Suplementos Nutricionais Neurônios/fisiologia Substâncias para Melhoria do Desempenho/administração & dosagem Teobromina/administração & dosagem Teofilina/administração & dosagem Vitaminas/administração & dosagem Zinco/administração & dosagem [Mh] Termos MeSH secundário: Adolescente Adulto Atenção Encéfalo/diagnóstico por imagem Cálcio na Dieta/administração & dosagem Cognição Estudos Cross-Over Método Duplo-Cego Potenciais Evocados Visuais Seguimentos Neuroimagem Funcional Seres Humanos Magnésio/administração & dosagem Adulto Jovem [Pt] Tipo de publicação: CLINICAL TRIAL; COMPARATIVE STUDY; JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL [Nm] Nome de substância: 0 (Calcium, Dietary); 0 (Performance-Enhancing Substances); 0 (Vitamins); 0 (guarana powder); 3G6A5W338E (Caffeine); C137DTR5RG (Theophylline); I38ZP9992A (Magnesium); J41CSQ7QDS (Zinc); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1703 [Cu] Atualização por classe: 170313 [Lr] Data última revisão: 170313 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 140927 [St] Status: MEDLINE [do] DOI: 10.1179/1476830514Y.0000000157

5 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27869315 [Au] Autor: Chlon-Rzepa G; Zagórska A; Zmudzki P; Bucki A; Kolaczkowski M; Partyka A; Wesolowska A; Kazek G; Gluch-Lutwin M; Siwek A; Starowicz G; Pawlowski M [Ad] Endereço: Department of Medicinal Chemistry, Jagiellonian University Medical College, Kraków, Poland. [Ti] Título: Aminoalkyl Derivatives of 8-Alkoxypurine-2,6-diones: Multifunctional 5-HT /5-HT Receptor Ligands and PDE Inhibitors with Antidepressant Activity. [So] Source: Arch Pharm (Weinheim);349(12):889-903, 2016 Dec. [Is] ISSN: 1521-4184 [Cp] País de publicação: Germany [La] Idioma: eng [Ab] Resumo: In the search for potential psychotropic agents, a new series of 3,7-dimethyl- and 1,3-dimethyl-8-alkoxypurine-2,6-dione derivatives of arylpiperazines, perhydroisoquinolines, or tetrahydroisoquinolines with flexible alkylene spacers (5-16 and 21-32) were synthesized and evaluated for 5-HT /5-HT receptor affinities as well as PDE4B1 and PDE10A inhibitory properties. The 1-(4-(4-(2-hydroxyphenyl)piperazin-1-yl)butyl)-3,7-dimethyl-8-propoxypurine-2,6-dione (16) and 7-(2-hydroxyphenyl)piperazinylalkyl-1,3-dimethyl-8-ethoxypurine-2,6-diones (31 and 32) as potent dual 5-HT /5-HT receptor ligands with antagonistic activity produced an antidepressant-like effect in the forced swim test in mice. This effect was similar to that produced by citalopram. All the tested compounds were stronger phosphodiesterase isoenzyme inhibitors than theophylline and theobromine. The most potent compounds, 15 and 16, were characterized by 51 and 52% inhibition, respectively, of PDE4B1 activity at a concentration of 10 M. Concerning the above findings, it may be assumed that the inhibition of PDE4B1 may impact on the signal strength and specificity resulting from antagonism toward the 5-HT and 5-HT receptors, especially in the case of compounds 15 and 16. This dual receptor and enzyme binding mode was analyzed and explained via molecular modeling studies. [Mh] Termos MeSH primário: Antidepressivos/farmacologia Inibidores de Fosfodiesterase/farmacologia Piperazinas/síntese química Piperazinas/farmacologia Antagonistas da Serotonina/farmacologia Agonistas de Receptores de Serotonina/farmacologia [Mh] Termos MeSH secundário: Animais Antidepressivos/síntese química Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/efeitos dos fármacos Resposta de Imobilidade Tônica/efeitos dos fármacos Isoenzimas/antagonistas & inibidores Isoquinolinas/síntese química Isoquinolinas/farmacologia Masculino Camundongos Modelos Moleculares Inibidores de Fosfodiesterase/síntese química Diester Fosfórico Hidrolases/efeitos dos fármacos Receptores de Serotonina/efeitos dos fármacos Antagonistas da Serotonina/síntese química Agonistas de Receptores de Serotonina/síntese química Relação Estrutura-Atividade Teobromina/farmacologia Teofilina/farmacologia [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Antidepressive Agents); 0 (Isoenzymes); 0 (Isoquinolines); 0 (Phosphodiesterase Inhibitors); 0 (Piperazines); 0 (Receptors, Serotonin); 0 (Serotonin Antagonists); 0 (Serotonin Receptor Agonists); 0 (serotonin 7 receptor); C137DTR5RG (Theophylline); EC 3.1.4.- (Pde10a protein, mouse); EC 3.1.4.- (Phosphoric Diester Hydrolases); EC 3.1.4.17 (Cyclic Nucleotide Phosphodiesterases, Type 4); EC 3.1.4.17 (PDE4B protein, mouse); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1704 [Cu] Atualização por classe: 170421 [Lr] Data última revisão: 170421 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 161122 [St] Status: MEDLINE [do] DOI: 10.1002/ardp.201600260

6 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27702941 [Au] Autor: Cornelis MC; Kacprowski T; Menni C; Gustafsson S; Pivin E; Adamski J; Artati A; Eap CB; Ehret G; Friedrich N; Ganna A; Guessous I; Homuth G; Lind L; Magnusson PK; Mangino M; Pedersen NL; Pietzner M; Suhre K; Völzke H; Bochud M; Spector TD; Grabe HJ; Ingelsson E; Swiss Kidney Project on Genes in Hypertension (SKIPOGH) team [Ad] Endereço: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, USA. [Ti] Título: Genome-wide association study of caffeine metabolites provides new insights to caffeine metabolism and dietary caffeine-consumption behavior. [So] Source: Hum Mol Genet;25(24):5472-5482, 2016 Dec 15. [Is] ISSN: 1460-2083 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Caffeine is the most widely consumed psychoactive substance in the world and presents with wide interindividual variation in metabolism. This variation may modify potential adverse or beneficial effects of caffeine on health. We conducted a genome-wide association study (GWAS) of plasma caffeine, paraxanthine, theophylline, theobromine and paraxanthine/caffeine ratio among up to 9,876 individuals of European ancestry from six population-based studies. A single SNP at 6p23 (near CD83) and several SNPs at 7p21 (near AHR), 15q24 (near CYP1A2) and 19q13.2 (near CYP2A6) met GW-significance (P < 5 × 10-8) and were associated with one or more metabolites. Variants at 7p21 and 15q24 associated with higher plasma caffeine and lower plasma paraxanthine/caffeine (slow caffeine metabolism) were previously associated with lower coffee and caffeine consumption behavior in GWAS. Variants at 19q13.2 associated with higher plasma paraxanthine/caffeine (slow paraxanthine metabolism) were also associated with lower coffee consumption in the UK Biobank (n = 94 343, P < 1.0 × 10-6). Variants at 2p24 (in GCKR), 4q22 (in ABCG2) and 7q11.23 (near POR) that were previously associated with coffee consumption in GWAS were nominally associated with plasma caffeine or its metabolites. Taken together, we have identified genetic factors contributing to variation in caffeine metabolism and confirm an important modulating role of systemic caffeine levels in dietary caffeine consumption behavior. Moreover, candidate genes identified encode proteins with important clinical functions that extend beyond caffeine metabolism. [Mh] Termos MeSH primário: Antígenos CD/genética Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética Cafeína/genética Citocromo P-450 CYP1A2/genética Citocromo P-450 CYP2A6/genética Imunoglobulinas/genética Glicoproteínas de Membrana/genética Receptores de Hidrocarboneto Arílico/genética [Mh] Termos MeSH secundário: Cafeína/sangue Café/genética Café/metabolismo Citocromo P-450 CYP1A2/metabolismo Grupo com Ancestrais do Continente Europeu Feminino Estudo de Associação Genômica Ampla Seres Humanos Masculino Polimorfismo de Nucleotídeo Único/genética Teobromina/sangue Teofilina/sangue [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (AHR protein, human); 0 (Antigens, CD); 0 (Basic Helix-Loop-Helix Transcription Factors); 0 (CD83 antigen); 0 (Coffee); 0 (Immunoglobulins); 0 (Membrane Glycoproteins); 0 (Receptors, Aryl Hydrocarbon); 3G6A5W338E (Caffeine); C137DTR5RG (Theophylline); EC 1.14.14.1 (CYP1A2 protein, human); EC 1.14.14.1 (CYP2A6 protein, human); EC 1.14.14.1 (Cytochrome P-450 CYP1A2); EC 1.14.14.1 (Cytochrome P-450 CYP2A6); OBD445WZ5P (Theobromine); Q3565Y41V7 (1,7-dimethylxanthine) [Em] Mês de entrada: 1706 [Cu] Atualização por classe: 170609 [Lr] Data última revisão: 170609 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 161006 [St] Status: MEDLINE [do] DOI: 10.1093/hmg/ddw334

7 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27472311 [Au] Autor: Monteiro JP; Alves MG; Oliveira PF; Silva BM [Ad] Endereço: Laboratory of Cell Biology and Unit for Multidisciplinary Research in Biomedicine (UMIB), Department of Microscopy, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, 4050-313 Porto, Portugal. jpspmonteiro@yahoo.com. [Ti] Título: Structure-Bioactivity Relationships of Methylxanthines: Trying to Make Sense of All the Promises and the Drawbacks. [So] Source: Molecules;21(8), 2016 Jul 27. [Is] ISSN: 1420-3049 [Cp] País de publicação: Switzerland [La] Idioma: eng [Ab] Resumo: Methylxanthines are a group of phytochemicals derived from the purine base xanthine and obtained from plant secondary metabolism. They are unobtrusively included in daily diet in common products as coffee, tea, energetic drinks, or chocolate. Caffeine is by far the most studied methylxanthine either in animal or epidemiologic studies. Theophylline and theobromine are other relevant methylxanthines also commonly available in the aforementioned sources. There are many disseminated myths about methylxanthines but there is increased scientific knowledge to discuss all the controversy and promise shown by these intriguing phytochemicals. In fact, many beneficial physiologic outcomes have been suggested for methylxanthines in areas as important and diverse as neurodegenerative and respiratory diseases, diabetes or cancer. However, there have always been toxicity concerns with methylxanthine (over)consumption and pharmacologic applications. Herein, we explore the structure-bioactivity relationships to bring light those enumerated effects. The potential shown by methylxanthines in such a wide range of conditions should substantiate many other scientific endeavors that may highlight their adequacy as adjuvant therapy agents and may contribute to the advent of functional foods. Newly designed targeted molecules based on methylxanthine structure may originate more specific and effective outcomes. [Mh] Termos MeSH primário: Compostos Fitoquímicos/química Compostos Fitoquímicos/farmacologia Xantinas/química Xantinas/farmacologia [Mh] Termos MeSH secundário: Animais Cacau/química Cafeína/química Cafeína/farmacologia Seres Humanos Estrutura Molecular Metabolismo Secundário Relação Estrutura-Atividade Teobromina/química Teobromina/farmacologia Teofilina/química Teofilina/farmacologia [Pt] Tipo de publicação: JOURNAL ARTICLE; REVIEW [Nm] Nome de substância: 0 (Phytochemicals); 0 (Xanthines); 28109-92-4 (methylxanthine); 3G6A5W338E (Caffeine); C137DTR5RG (Theophylline); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1704 [Cu] Atualização por classe: 170414 [Lr] Data última revisão: 170414 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160730 [St] Status: MEDLINE

8 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27419646 [Au] Autor: Sonu VK; Islam MM; Rohman MA; Mitra S [Ad] Endereço: Centre for Advanced Studies, Department of Chemistry, North-Eastern Hill University, Shillong, 793 022, India. [Ti] Título: Lysozyme binding ability toward psychoactive stimulant drugs: Modulatory effect of colloidal metal nanoparticles. [So] Source: Colloids Surf B Biointerfaces;146:514-22, 2016 Oct 01. [Is] ISSN: 1873-4367 [Cp] País de publicação: Netherlands [La] Idioma: eng [Ab] Resumo: The interaction and binding behavior of the well-known psychoactive stimulant drugs theophylline (THP) and theobromine (THB) with lysozyme (LYS) was monitored by in-vitro fluorescence titration and molecular docking calculations under physiological condition. The quenching of protein fluorescence on addition of the drugs is due to the formation of protein-drug complex in the ground state in both the cases. However, the binding interaction is almost three orders of magnitude stronger in THP, which involves mostly hydrogen bonding interaction in comparison with THB where hydrophobic binding plays the predominant role. The mechanism of fluorescence quenching (static type) remains same also in presence of gold and silver nanoparticles (NPs); however, the binding capacity of LYS with the drugs changes drastically in comparison with that in aqueous buffer medium. While the binding affinity of LYS to THB increases ca. 100 times in presence of both the NPs, it is seen to decrease drastically (by almost 1000 fold) for THP. This significant modulation in binding behavior indicates that the drug transportation capacity of LYS can be controlled significantly with the formation protein-NP noncovalent assembly system as an efficient delivery channel. [Mh] Termos MeSH primário: Coloides/química Nanopartículas Metálicas/administração & dosagem Muramidase/metabolismo Teobromina/metabolismo Teofilina/metabolismo Vasodilatadores/metabolismo [Mh] Termos MeSH secundário: Animais Sítios de Ligação Galinhas Fluorescência Ouro/química Ligações de Hidrogênio Interações Hidrofóbicas e Hidrofílicas Nanopartículas Metálicas/química Simulação de Acoplamento Molecular Muramidase/química Ligação Proteica Prata/química Espectrometria de Fluorescência Teobromina/química Teofilina/química Vasodilatadores/química [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Colloids); 0 (Vasodilator Agents); 3M4G523W1G (Silver); 7440-57-5 (Gold); C137DTR5RG (Theophylline); EC 3.2.1.17 (Muramidase); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1702 [Cu] Atualização por classe: 170214 [Lr] Data última revisão: 170214 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160716 [St] Status: MEDLINE

9 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27157734 [Au] Autor: Aswini KK; Vinu Mohan AM; Biju VM [Ad] Endereço: Department of Chemistry, National Institute of Technology, Tiruchirappalli, TamilNadu 620 015, India. Electronic address: aswinikk@ymail.com. [Ti] Título: Molecularly imprinted poly(4-amino-5-hydroxy-2,7-naphthalenedisulfonic acid) modified glassy carbon electrode as an electrochemical theophylline sensor. [So] Source: Mater Sci Eng C Mater Biol Appl;65:116-25, 2016 Aug 01. [Is] ISSN: 1873-0191 [Cp] País de publicação: Netherlands [La] Idioma: eng [Ab] Resumo: Theophylline is an inexpensive drug employed in asthma and chronic obstructive pulmonary disorder medications and is toxic at higher concentration. The development of a molecularly imprinted polymer based theophylline electrochemical sensor on glassy carbon electrode by the electropolymerization of 4-amino-5-hydroxy-2,7-naphthalenedisulfonic acid is being discussed in this work. The MIP modification enhances the theophylline recognition ability and the electron transfer kinetics of the bare electrode. The parameters, controlling the performance of the imprinted polymer based sensor, like number of electropolymerization cycles, composition of the pre-polymerization mixture, pH and immersion time were investigated and optimized. The interaction energy and the most stable conformation of the template-monomer complex in the pre-polymerization mixture were determined computationally using ab initio calculations based on density functional theory. The amperometric measurements showed that the developed sensor has a method detection limit of 0.32µM for the dynamic range of 0.4 to 17µM, at optimized conditions. The transducer possesses appreciable selectivity in the presence of structurally similar interferents such as theobromine, caffeine and doxofylline. The developed sensor showed remarkable stability and reproducibility and was also successfully employed in theophylline detection from commercially available tablets. [Mh] Termos MeSH primário: Técnicas Eletroquímicas Impressão Molecular Polímeros/química Teofilina/análise [Mh] Termos MeSH secundário: Cafeína/química Carbono/química Espectroscopia Dielétrica Eletrodos Seres Humanos Concentração de Íons de Hidrogênio Limite de Detecção Microscopia de Força Atômica Teobromina/química Teofilina/análogos & derivados Teofilina/sangue Teofilina/química Teofilina/urina Compostos de Estanho/química [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Polymers); 0 (Tin Compounds); 3G6A5W338E (Caffeine); 71243-84-0 (indium tin oxide); 7440-44-0 (Carbon); C137DTR5RG (Theophylline); MPM23GMO7Z (doxofylline); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1704 [Cu] Atualização por classe: 170410 [Lr] Data última revisão: 170410 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160510 [St] Status: MEDLINE

10 / 1527

MEDLINE

seleciona para imprimir Fotocópia Texto completo

[PMID]: 27132838 [Au] Autor: Alañón ME; Castle SM; Siswanto PJ; Cifuentes-Gómez T; Spencer JP [Ad] Endereço: Food and Nutritional Sciences Department, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, RG6 6AP Reading, United Kingdom. Electronic address: a.p.elena@reading.ac.uk. [Ti] Título: Assessment of flavanol stereoisomers and caffeine and theobromine content in commercial chocolates. [So] Source: Food Chem;208:177-84, 2016 Oct 01. [Is] ISSN: 0308-8146 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Assessment of the flavanol composition of 41 commercial chocolates was by HPLC-DAD. Among individual flavonols ranged from 0.095 to 3.264mgg(-1), epicatechin was the predominant flavanol accounting for 32.9%. Contrary to catechin, epicatechin was a reliable predictive value of the polyphenol content. Conversely the percentage of theobromine used as a proxy measure for nonfat cocoa solids (NFCS) was not a good predictor of epicatechin or flavanol content. In a further chiral analysis, the naturally occurring forms of cocoa flavanols, (-)-epicatechin and (+)-catechin, was determined joint the occurrence of (+)-epicatechin and (-)-catechin due to the epimerization reactions produced in chocolate manufacture. (-)-Epicatechin, the most bioactive compound and predominant form accounted of 93%. However, no positive correlation was found with% cocoa solids, the most significant quality parameter. [Mh] Termos MeSH primário: Cafeína/análise Chocolate/análise Flavonoides/análise Teobromina/análise [Mh] Termos MeSH secundário: Biflavonoides/análise Cacau/química Catequina/análise Cromatografia Líquida de Alta Pressão Análise de Alimentos Polifenóis/análise Proantocianidinas/análise Estereoisomerismo Xantinas/análise [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Biflavonoids); 0 (Flavonoids); 0 (Polyphenols); 0 (Proanthocyanidins); 0 (Xanthines); 28109-92-4 (methylxanthine); 3G6A5W338E (Caffeine); 4852-22-6 (procyanidin); 8R1V1STN48 (Catechin); OBD445WZ5P (Theobromine) [Em] Mês de entrada: 1702 [Cu] Atualização por classe: 170206 [Lr] Data última revisão: 170206 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160503 [St] Status: MEDLINE

---

página 1 de 153

ir para página

Refinar a pesquisa

Base de dados : MEDLINE

Formulário avançado

		Pesquisar	no campo
1			PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2
2	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2
3	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2

Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde