Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
Nat Commun ; 13(1): 888, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173144

RESUMO

Celiac disease (CeD) is an autoimmune disorder induced by consuming gluten proteins from wheat, barley, and rye. Glutens resist gastrointestinal proteolysis, resulting in peptides that elicit inflammation in patients with CeD. Despite well-established connections between glutens and CeD, chemically defined, bioavailable peptides produced from dietary proteins have never been identified from humans in an unbiased manner. This is largely attributable to technical challenges, impeding our knowledge of potentially diverse peptide species that encounter the immune system. Here, we develop a liquid chromatographic-mass spectrometric workflow for untargeted sequence analysis of the urinary peptidome. We detect over 600 distinct dietary peptides, of which ~35% have a CeD-relevant T cell epitope and ~5% are known to stimulate innate immune responses. Remarkably, gluten peptides from patients with CeD qualitatively and quantitatively differ from controls. Our results provide a new foundation for understanding gluten immunogenicity, improving CeD management, and characterizing the dietary and urinary peptidomes.


Assuntos
Doença Celíaca/imunologia , Glutens/análise , Proteoma/análise , Urina/química , Sequência de Aminoácidos , Doença Celíaca/patologia , Cromatografia Líquida , Epitopos de Linfócito T/imunologia , Glutens/imunologia , Glutens/metabolismo , Hordeum/química , Humanos , Espectrometria de Massas , Secale/química , Linfócitos T/imunologia , Triticum/química
2.
J Stud Alcohol Drugs ; 83(1): 153-158, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35040771

RESUMO

OBJECTIVE: The purpose of this study was to identify priority variables to evaluate alcohol brief interventions from the perspective of experts in the field in Latin America. METHOD: A two-round Delphi procedure was carried out through online surveys of 465 individuals from 18 Latin American countries, including core outcome set developers, researchers, health professionals, users of healthcare services, journal editors, members of nongovernmental organizations, and policymakers. The questionnaire, in Spanish and Portuguese, rated 101 variables according to their relevance to the efficacy and effectiveness of brief interventions. RESULTS: Round 1 yielded 47 variables that met the consensus criterion of at least 70% of participants; Round 2 yielded 63 variables. To reduce the possible effect of varying levels of expertise, data were analyzed by subgroup, with consensus defined as 70% of each subgroup rating a variable as critical. Seventeen outcome variables met this criterion, 14 from the initial set and 3 suggested by the participants in Round 1. CONCLUSIONS: Only four outcomes coincide with the findings of a similar international Delphi study that underrepresented Latin American countries. The findings point to the importance of including a wider variety of professionals and cultural backgrounds in international consensus panels to minimize the risk of predominance of a single perspective.


Assuntos
Intervenção em Crise , Avaliação de Resultados em Cuidados de Saúde , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/prevenção & controle , Técnica Delphi , Humanos , América Latina/epidemiologia
3.
Nature ; 595(7867): 415-420, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34262212

RESUMO

Gut microorganisms modulate host phenotypes and are associated with numerous health effects in humans, ranging from host responses to cancer immunotherapy to metabolic disease and obesity. However, difficulty in accurate and high-throughput functional analysis of human gut microorganisms has hindered efforts to define mechanistic connections between individual microbial strains and host phenotypes. One key way in which the gut microbiome influences host physiology is through the production of small molecules1-3, yet progress in elucidating this chemical interplay has been hindered by limited tools calibrated to detect the products of anaerobic biochemistry in the gut. Here we construct a microbiome-focused, integrated mass-spectrometry pipeline to accelerate the identification of microbiota-dependent metabolites in diverse sample types. We report the metabolic profiles of 178 gut microorganism strains using our library of 833 metabolites. Using this metabolomics resource, we establish deviations in the relationships between phylogeny and metabolism, use machine learning to discover a previously undescribed type of metabolism in Bacteroides, and reveal candidate biochemical pathways using comparative genomics. Microbiota-dependent metabolites can be detected in diverse biological fluids from gnotobiotic and conventionally colonized mice and traced back to the corresponding metabolomic profiles of cultured bacteria. Collectively, our microbiome-focused metabolomics pipeline and interactive metabolomics profile explorer are a powerful tool for characterizing microorganisms and interactions between microorganisms and their host.


Assuntos
Bactérias/metabolismo , Microbioma Gastrointestinal , Metaboloma , Metabolômica/métodos , Animais , Bactérias/classificação , Bactérias/genética , Bacteroides/genética , Bacteroides/metabolismo , Genes Bacterianos/genética , Genômica , Interações entre Hospedeiro e Microrganismos , Humanos , Masculino , Camundongos , Nitrogênio/metabolismo , Fenótipo , Filogenia
4.
Curr Top Med Chem ; 20(9): 713-719, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31985378

RESUMO

BACKGROUND: Due to the rapid development of microbial resistance, finding new molecules became urgent to counteract this problem. OBJECTIVE: The objective of this work is to access 1,2,3-triazene-1,3-disubstituted, a class of molecule with high therapeutic potential. METHODS: Here we describe the access to 17 new triazene including six with an imidazole-1,2,3-triazene moiety and eleven with an alkyl-1,2,3-triazene moiety and their evaluation against five strains: two gram (-): Escherichia coli ATCC 25921 and Pseudomonas aeruginosa ATCC 27253; two gram (+) : Staphylococcus aureus ATCC 38213 and Enterococcus faecalis ATCC 29212; and one fungi: Candida albicans ATCC 24433. RESULTS: All strains were sensitive and the best MIC, 0.28 µM, is observed for 4c against Escherichia coli ATCC 25921. Compound 9, 3-isopropynyltriazene, appears to be the most interesting since it is active on the five evaluated strains with satisfactory MIC 0.32 µM against Escherichia coli and Pseudomonas aeruginosa and 0.64 µM against Enterococcus faecalis and Pseudomonas aeruginosa. CONCLUSION: Comparing the structure activity relationship, electron withdrawing groups appear to increase antimicrobial activity.


Assuntos
Anti-Infecciosos/química , Bibliotecas de Moléculas Pequenas/química , Triazenos/química , Candida albicans/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Triazenos/farmacologia
5.
J Invest Dermatol ; 132(4): 1125-32, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22277946

RESUMO

Systemic sclerosis (SSc) is a connective tissue disorder characterized by skin and visceral fibrosis, microvascular damage, and autoimmunity. HOCl-induced mouse SSc is a murine model that mimics the main features of the human disease, especially the activation and hyperproliferation rate of skin fibroblasts. We demonstrate here the efficiency of a tellurium-based catalyst 2,3-bis(phenyltellanyl)naphthoquinone ((PHTE)(2)NQ) in the treatment of murine SSc, through its selective cytotoxic effects on activated SSc skin fibroblasts. SSc mice treated with (PHTE)(2)NQ displayed a significant decrease in lung and skin fibrosis and in alpha-smooth muscle actin (α-SMA) expression in the skin compared with untreated mouse SSc animals. Serum concentrations of advanced oxidation protein products, nitrate, and anti-DNA topoisomerase I autoantibodies were increased in SSc mice, but were significantly reduced in SSc mice treated with (PHTE)(2)NQ. To assess the mechanism of action of (PHTE)(2)NQ, the cytotoxic effect of (PHTE)(2)NQ was compared in normal fibroblasts and in mouse SSc skin fibroblasts. ROS production is higher in mouse SSc fibroblasts than in normal fibroblasts, and was still increased by (PHTE)(2)NQ to reach a lethal threshold and kill mouse SSc fibroblasts. Therefore, the effectiveness of (PHTE)(2)NQ in the treatment of mouse SSc seems to be linked to the selective pro-oxidative and cytotoxic effects of (PHTE)(2)NQ on hyperproliferative fibroblasts.


Assuntos
Ácido Hipocloroso/efeitos adversos , Compostos Organometálicos/uso terapêutico , Escleroderma Sistêmico/induzido quimicamente , Escleroderma Sistêmico/prevenção & controle , Telúrio/uso terapêutico , Actinas/metabolismo , Animais , Autoanticorpos/sangue , Células Cultivadas , DNA Topoisomerases Tipo I/imunologia , Modelos Animais de Doenças , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB C , Naftoquinonas/farmacologia , Naftoquinonas/uso terapêutico , Óxido Nítrico/sangue , Compostos Organometálicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Escleroderma Sistêmico/metabolismo , Pele/efeitos dos fármacos , Pele/patologia , Telúrio/farmacologia
6.
J Biomed Nanotechnol ; 7(3): 395-405, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21830480

RESUMO

Many sulfur compounds are known to exhibit widespread antimicrobial activity. The latter is often the result of an intricate redox biochemistry whereby reactive sulfur species, such as organic polysulfanes, interact with pivotal cellular signaling pathways. The S8 unit in elemental sulfur resembles certain aspects of the chemistry of polysulfanes. As a consequence, water-soluble S8-sulfur nanoparticles are active against some smaller organisms, including nematodes, yet are non-toxic against human cells. In contrast, selenium and tellurium nanoparticles are less active. Together, the ease of production of the sulfur nanoparticles, their chemical stability in aqueous dispersion, amenable physical properties and selective toxicity, turn sulfur nanoparticles into promising antimicrobial prototypes for medical as well as agricultural applications.


Assuntos
Anti-Infecciosos/farmacologia , Nanopartículas/química , Plasmodium falciparum/efeitos dos fármacos , Enxofre/farmacologia , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Eletroquímica , Humanos , Concentração Inibidora 50 , Modelos Biológicos , Nematoides/efeitos dos fármacos , Enxofre/química
7.
Leuk Lymphoma ; 52(7): 1407-11, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21476834

RESUMO

Precursor transformation, clonal sustenance, and therapeutic resistance in cancer are significantly mediated by deregulated reactive oxygen species (ROS), which primarily act as DNA-stressors. Here, we demonstrate that elevated ROS in chronic lymphocytic leukemia (CLL) may represent a promising therapeutic target. We designed organochalcogens, which, based on a 'sensor/effector' principle, would confer selective cytotoxicity through the generation of intolerably high ROS levels preferentially in CLL cells, as these carry a high-level redox burden. Our novel compounds show an encouraging profile of efficient induction of apoptosis, low normal cell toxicity, and promising chemotherapy synergism. These findings warrant further mechanistic and preclinical studies of this therapeutic principle in CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B/metabolismo , Compostos Orgânicos/metabolismo , Compostos Orgânicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Catálise , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Glutationa/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Compostos Orgânicos/uso terapêutico , Oxirredução/efeitos dos fármacos , Vidarabina/análogos & derivados , Vidarabina/farmacologia , Vidarabina/uso terapêutico
8.
Nat Prod Commun ; 6(1): 31-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21366040

RESUMO

Flavones such as chrysin show structural similarities to androgens, the substrates of human aromatase, which converts androgens to estrogens. Aromatase is a key target in the treatment of hormone-dependent tumors, including breast cancer. Flavone-based aromatase inhibitors are of growing interest, and chrysin in particular provides a (natural) lead structure. This paper reports multicomponent synthesis as a means for facile modification of the chrysin core structure in order to add functional elements. A Mannich-type reaction was used to synthesize a range of mono- and disubstituted chrysin derivatives, some of which are more effective aromatase inhibitors than the benchmark compound, aminoglutethimide. Similarly, the reaction of chrysin with various isonitriles and acetylene dicarboxylates results in a new class of flavone derivatives, tricyclic pyrano-flavones which also inhibit human aromatase. Multicomponent reactions involving flavones therefore enable the synthesis of a variety of derivatives, some of which may be useful as anticancer agents.


Assuntos
Inibidores da Aromatase/síntese química , Flavonoides/síntese química , Inibidores da Aromatase/química , Inibidores da Aromatase/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Humanos , Concentração Inibidora 50 , Solubilidade
10.
J Med Chem ; 53(19): 6954-63, 2010 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-20836556

RESUMO

Many tumor cells exhibit a disturbed intracellular redox state resulting in higher levels of reactive oxygen species (ROS). As these contribute to tumor initiation and sustenance, catalytic redox agents combining significant activity with substrate specificity promise high activity and selectivity against oxidatively stressed malignant cells. We describe here the design and synthesis of novel organochalcogen based redox sensor/effector catalysts. Their selective anticancer activity at submicromolar and low micromolar concentrations was established here in a range of tumor entities in various biological systems including cell lines, primary tumor cell cultures, and animal models. In the B-cell derived chronic lymphocytic leukemia (CLL), for instance, such compounds preferentially induce apoptosis in the cancer cells while peripheral blood mononuclear cells (PBMC) from healthy donors and the subset of normal B-cells remain largely unaffected. In support of the concept of sensor/effector based ROS amplification, we are able to demonstrate that underlying this selective activity against CLL cells are pre-existing elevated ROS levels in the leukemic cells compared to their nonmalignant counterparts. Furthermore, the catalysts act in concert with certain chemotherapeutic drugs in several carcinoma cell lines to decrease cell proliferation while showing no such interactions in normal cells. Overall, the high efficacy and selectivity of (redox) catalytic sensor/effector compounds warrant further, extensive testing toward transfer into the clinical arena.


Assuntos
Antineoplásicos/síntese química , Compostos Organosselênicos/síntese química , Quinonas/síntese química , Sulfetos/síntese química , Telúrio , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Catálise , Linhagem Celular , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Camundongos , Naftoquinonas/síntese química , Naftoquinonas/química , Naftoquinonas/farmacologia , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacologia , Oxirredução , Quinonas/química , Quinonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Sulfetos/química , Sulfetos/farmacologia
11.
Chemistry ; 16(36): 10920-8, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20677196

RESUMO

Various human diseases, including different types of cancer, are associated with a disturbed intracellular redox balance and oxidative stress (OS). The past decade has witnessed the emergence of redox-modulating compounds able to utilize such pre-existing disturbances in the redox state of sick cells for therapeutic advantage. Selenium- and tellurium-based agents turn the oxidizing redox environment present in certain cancer cells into a lethal cocktail of reactive species that push these cells over a critical redox threshold and ultimately kill them through apoptosis. This kind of toxicity is highly selective: normal, healthy cells remain largely unaffected, since changes to their naturally low levels of oxidizing species produce little effect. To further improve selectivity, multifunctional sensor/effector agents are now required that recognize the biochemical signature of OS in target cells. The synthesis of such compounds provides interesting challenges for chemistry in the future.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Citotoxinas/química , Citotoxinas/farmacologia , Metaloporfirinas/química , Metaloporfirinas/farmacologia , Selênio/química , Selênio/farmacologia , Telúrio/química , Telúrio/farmacologia , Antineoplásicos/uso terapêutico , Antioxidantes/uso terapêutico , Linhagem Celular Tumoral , Humanos , Metaloporfirinas/uso terapêutico , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Selênio/uso terapêutico , Telúrio/uso terapêutico
12.
Dtsch Med Wochenschr ; 135(9): 385-9, 2010 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-20180162

RESUMO

OBJECTIVE: Febrile neutropenia (FN) is a common toxic side effect of myelosuppressive chemotherapy. The cost-effectiveness of primary prophylaxis (PP) of FN with granulocyte colony stimulating growth factor (G-CSF) filgrastim for six or eleven days was compared to single dose pegfilgrastim in patients with early breast cancer receiving chemotherapy (>or= 20 % FN risk) as simulated in a model. METHODS: Based on a decision-analytical model we conducted a cost-effectiveness analysis (CEA) and a cost-utility analysis (CUA) from the perspective of the Statutory Health Insurance (SHI) in Germany. The model simulated three clinical alternatives being built on each other, that pegfilgrastim and filgrastim had differential impact on (1) the risk of FN, (2) on FN-related mortality, and (3) on the achieved chemotherapy relative dose intensity (RDI) leading to gain in long-term survival. RESULTS: Assuming a 5.5 % lower risk of FN for PP with pegfilgrastim than an 11-day course of filgrastim provided - from the perspective of the SHI - a cost saving of Euro 2,229. A gain of 0.039 quality-adjusted life-years (QALY) resulted when the third alternative was used. Assuming a 10.5 % lower risk of FN for PP with pegfilgrastim than a 6-day filgrastim course, the third alternative showed an incremental cost-effectiveness ratio (ICER) of Euro 17.165 per life-year gained (LYG) and Euro 18.324 per QALY with 0.074 QALYs gained. CONCLUSION: These results indicate that PP with pegfilgrastim is cost saving compared to 11-day use of filgrastim and cost-effective compared to 6-day use of filgrastim in patients with breast cancer treated in Germany.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/economia , Custos de Medicamentos/estatística & dados numéricos , Febre de Causa Desconhecida/induzido quimicamente , Febre de Causa Desconhecida/prevenção & controle , Fator Estimulador de Colônias de Granulócitos/economia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Programas Nacionais de Saúde/economia , Neutropenia/induzido quimicamente , Neutropenia/prevenção & controle , Adulto , Idoso , Antineoplásicos/administração & dosagem , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Análise Custo-Benefício , Esquema de Medicação , Feminino , Febre de Causa Desconhecida/economia , Filgrastim , Alemanha , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neutropenia/economia , Polietilenoglicóis , Anos de Vida Ajustados por Qualidade de Vida , Proteínas Recombinantes , Análise de Sobrevida
13.
Org Biomol Chem ; 7(22): 4753-62, 2009 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-19865713

RESUMO

Various human illnesses, including several types of cancer and infectious diseases, are related to changes in the cellular redox homeostasis. During the last decade, several approaches have been explored which employ such disturbed redox balances for the benefit of therapy. Compounds able to modulate the intracellular redox state of cells have been developed, which effectively, yet also selectively, appear to kill cancer cells and a range of pathogenic microorganisms. Among the various agents employed, certain redox catalysts have shown considerable promise since they are non-toxic on their own yet develop an effective, often selective cytotoxicity in the presence of the 'correct' intracellular redox partners. Aminoalkylation, amide coupling and multicomponent reactions are suitable synthetic methods to generate a vast number of such multifunctional catalysts, which are chemically diverse and, depending on their structure, exhibit various interesting biological activities.


Assuntos
Antioxidantes/síntese química , Selênio/química , Telúrio/química , Alquilação/efeitos dos fármacos , Amidas/química , Aminação/efeitos dos fármacos , Antioxidantes/farmacologia , Sítios de Ligação , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Testes de Sensibilidade Microbiana , Oxirredução/efeitos dos fármacos , Testes de Sensibilidade Parasitária , Plasmodium falciparum/citologia , Plasmodium falciparum/efeitos dos fármacos , Trichophyton/efeitos dos fármacos
14.
Chem Commun (Camb) ; (31): 4702-4, 2009 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-19641815

RESUMO

Multicomponent Passerini and Ugi reactions enable the fast and efficient synthesis of redox-active multifunctional selenium and tellurium compounds, of which some show considerable cytotoxicity against specific cancer cells.


Assuntos
Antineoplásicos/síntese química , Compostos Organometálicos/síntese química , Selênio/química , Telúrio/química , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Compostos Organometálicos/química , Oxirredução
15.
Clin Endocrinol (Oxf) ; 70(5): 706-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18710461

RESUMO

OBJECTIVE: Rett syndrome is a progressive neurological disorder affecting almost exclusively females after age 6 months and characterised by acquired microcephaly, psychomotor retardation, growth failure, purposeless hand movements, autistic-like behaviour and wide-based and stiff legged gait. Leptin and adiponectin, peptides secreted by adipose tissue, are involved in the regulation of body weight and energy expenditure. DESIGN AND PATIENTS: We investigated in patients with Rett syndrome the variations of plasma leptin and adiponectin and their relation over a 2-year period. Sixteen female patients, mean age at the basal time 9.4 +/- 4.3 years, with classical Rett syndrome were enrolled. Controls were 16 healthy female subjects, mean age at the basal time 9.9 +/- 3.4 years. MEASUREMENTS: Blood samples were withdrawn in the morning at the baseline, 12 months after and 24 months after; plasma leptin and adiponectin concentrations were detected by ELISA. RESULTS: In patients, leptin concentrations significantly increased, while adiponectin concentrations significantly decreased. Both leptin and adiponectin values were significantly higher than those found in controls at each time. Leptin significantly correlated with adiponectin in patients, while there was not a significant correlation in controls. CONCLUSION: Since all patients were not obese, we might hypothesize that in Rett syndrome leptin and adiponectin might participate to clinical manifestations other than weight balance.


Assuntos
Leptina/sangue , Síndrome de Rett/sangue , Adiponectina/sangue , Adiposidade , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Proteína 2 de Ligação a Metil-CpG/genética , Mutação , Síndrome de Rett/genética
16.
J Pediatr ; 150(1): 37-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17188610

RESUMO

OBJECTIVE: To describe in patients with Rett syndrome (classic and preserved-speech variant) plasma leptin levels and their relationship to BMI (body mass index) and age. STUDY DESIGN: Female patients (n = 48; age range 3-20 years) affected by classic Rett syndrome were enrolled into the study. Eleven female patients, age range 3 to 20 years, with preserved-speech variant Rett syndrome were included in the study. Controls were 24 healthy female subjects, age range 3 to 20 years. Blood samples (3 mL) were withdrawn from an antecubital vein in the morning; plasma leptin concentrations were detected by enzyme-linked immunosorbent assay method. RESULTS: Patients with classic Rett syndrome and preserved-speech variant had leptin values significantly higher than controls. Leptin concentrations did not significantly differ between patients with classic Rett and preserved-speech variant. Leptin values positively correlated with age and BMI. CONCLUSIONS: Because in all patients the increased leptin concentrations were not associated to obesity, we hypothesize that in patients with Rett syndrome leptin might participate to clinical manifestations other than weight balance.


Assuntos
Leptina/sangue , Síndrome de Rett/sangue , Adolescente , Adulto , Fatores Etários , Biomarcadores/sangue , Índice de Massa Corporal , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Itália/epidemiologia , Prevalência , Síndrome de Rett/epidemiologia , Fatores de Risco
17.
Nutr Metab Cardiovasc Dis ; 16(3): 210-4, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16580588

RESUMO

BACKGROUND AND AIM: Serotonin (5-HT), a decarboxylated derivative of tryptophan, is synthesized in the enterochromaffin cells and released into blood stream to be incorporated into platelets. At the site of endothelial lesions, platelets aggregate and secrete 5-HT that presents several vascular actions involved in thrombosis and atherogenesis. In fact, 5-HT may induce vasoconstriction in the presence of endothelial injury, aggregation of platelets, and mitogenesis of arterial smooth muscle cells and endothelial cells. It may also contribute to the vascular inflammation associated with atherogenesis by increasing the synthesis of Interleukin-6 in vascular smooth muscle cells. We evaluated serotonin levels in plasma and platelets of patients with unstable angina and ischemic stroke, to identify an association between serotonin and atherosclerosis of coronary and cerebral arteries. METHODS AND RESULTS: Twenty patients (14 men, 6 women, mean age 69 +/- 10 years) with unstable angina and 15 patients (7 men, 8 women, mean age 81 +/- 10 years) with ischemic stroke were included in the study. Twenty-four healthy subjects matched for age and sex constituted the control group. Blood samples were drawn in the morning to determine plasma and platelet concentrations of serotonin. In patients with unstable angina serotonin levels in platelets were significantly lower (p < 0.001) than those observed in controls, while serotonin concentrations in plasma did not significantly differ from those found in controls. In patients affected by stroke serotonin levels in plasma and in platelets did not significantly differ from those found in normal subjects. CONCLUSIONS: Our findings may contribute to the knowledge to different mechanisms involved in the pathogenesis of cardiac and cerebral ischemia.


Assuntos
Angina Instável/sangue , Plaquetas/metabolismo , Doença da Artéria Coronariana/sangue , Serotonina/sangue , Acidente Vascular Cerebral/sangue , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Serotonina/análise , Triptofano/metabolismo
18.
Neuropediatrics ; 35(1): 36-8, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15002050

RESUMO

BACKGROUND: In Rett syndrome the autonomic nervous system is abnormal at various levels, from the central to the peripheral nervous system. A role for serotoninergic dysfunction has been suggested. OBJECTIVES: The aim of our study was to evaluate the relation between cardiac dysautonomia (expressed by means of heart rate variability) and plasma serotonin levels in girls affected with Rett syndrome. Heart rate variability and plasma serotonin levels were evaluated in 28 Rett girls aged 1-14 years. A Pearson correlation was used to determine whether there was a relationship between plasma serotonin levels and each heart rate variability parameter. RESULTS: In untreated Rett girls the plasma serotonin levels correlated with the sympathovagal balance, as expressed by the low frequency (LF) to high frequency (HF) ratio (p<0.05). CONCLUSIONS: Our results suggest that cardiac dysautonomia could be linked to serotoninergic dysfunction and that treatment with a serotonin analogue could be useful in improving the sympathovagal balance.


Assuntos
Doenças do Sistema Nervoso Autônomo/sangue , Doenças do Sistema Nervoso Autônomo/complicações , Cardiopatias/sangue , Cardiopatias/complicações , Síndrome de Rett/sangue , Síndrome de Rett/complicações , Serotonina/sangue , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente
19.
West Indian med. j ; 50(Suppl 7): 44, Dec. 2001.
Artigo em Inglês | MedCarib | ID: med-21

RESUMO

Many of the new materials and techniques used in endodontics (root canal treatment) require considerable practice to master and many require continuing education courses to allow formal instruction. Nothing is known regarding techniques employed and views on continuing professional education (CPE) in endodotics by dentists in Trinidad and Tobago. With the shift toward evidence-based dentistry and rising patient expectation of quality oral health care, a survey was conducted to describe these issues. A self-administered postal questionnaire was sent to all registered dentists in Trinidad and Tobago. Seventy dentists responded after two mailings. Most respondents worked primarily in private practice (85.5 percent). Years since qualification ranged from 2 to 45 years and 54.3 percent were qualified for more than 10 years. Most frequent treatment of an acute dental abcess involved opening, preparing the canal(s), dressing and prescribing antibiotics (40 percent). Forty-one respondents (58.6 percent) ocassionally completed root canal treatment in a single visit. Isolation of the tooth for molar root treatment always caused difficulty for thirty-five respondents (50 percent) and rubber dam isolation was used routinely by only nine respondents (12.9 percent). Most respondents either filed (20 percent) or reamed (18 .6 percent) for canal preparation usually using K files. Thirty-three respondents (47 percent) used sodium hypochlorite to irrigate the tooth and thirty-one (44.3 percent) used cold lateral condensation of gutta percha to obturate. Thirty-four respondents (48.6 percent) subscribed to professional journals and sixty-seven (95.7 percent) had attended some form of Continuing Professional Education. Sixty-seven (95.7 percent) of respondents would attend CPE in endodontics if available in Trinidad and Tobago, with most (72.9 percent) preferring a lecture/seminar format addressing problem-solving and new techniques. Respondents to this survey showed use of a wide range of techniques and materials but still expressed considerable interest in developing their skills in endodontics through formal CPE. (AU)


Assuntos
Endodontia/métodos , Odontólogos , Educação Continuada em Odontologia , Tratamento do Canal Radicular/métodos , Trinidad e Tobago , Padrões de Prática Odontológica/tendências , Estudos Transversais , Coleta de Dados
20.
West Indian Med J ; 50(2): 111-6, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11677906

RESUMO

Cytochrome c oxidase, the final member of the electron transport chain, is crucial to respiration and also contributes to the synthesis of cellular ATP. The total absence of this enzyme is incompatible with life and its deficiency or malfunction leads to a number of serious disease states. Understanding the mechanism of action of this enzyme, which is an important prerequisite to unravelling its role in the pathogenesis of disease states, is hampered by the lack of suitable enzyme models. The bovine enzyme, which is commonly used, is enormously complex and the bacterial enzymes, which are structurally simple, appear to follow a different mechanism of action. The hammer head shark is a seasonal resident of the warm waters of the Caribbean Sea. The work presented here indicates that, like the bovine enzyme, the enzyme of the heart of this shark (i) possesses thirteen subunits and two substrate binding sites and (ii) exhibits biphasic kinetics. The work also confirms that, unlike the bovine enzyme which is dimeric, the shark enzyme functions as a monomer. Given this latter simplifying feature, in conjunction with its kinetic and structural similarities to the more complex mammalian varieties, we propose that shark heart cytochrome c oxidase replace the bovine and bacterial forms as the enzyme of choice for model studies.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/fisiologia , Tubarões , Animais , Bovinos , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/farmacologia , Humanos , Miocárdio/enzimologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...