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1.
Am J Hypertens ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016523

RESUMO

BACKGROUND: myostatin is a protein compound structurally related to the TGF-beta protein, which plays a pivotal role in regulating muscle growth and extracellular matrix production. exerts both profibrotic and antihypertrophic effects on vascular smooth muscle cells. Aim of the study was to explore the potential association between serum myostatin levels (sMSTN) and carotid-femoral pulse-wave velocity (cf-PWV), carotid-radial pulse wave velocity (cr-PWV), and their ratio (PWVr), in a cohort of healthy adolescents. METHODS: a cohort of 128 healthy subjects (mean age 17±2 years, 59% male) was randomly selected from participants to the MACISTE (Metabolic And Cardiovascular Investigation at School, TErni) study. sMSTN was assessed utilizing an enzyme-linked immunosorbent assay. PWVs were measured in the supine position using high-fidelity applanation tonometry. RESULTS: The mean cf-PWV was 5.1±0.9 m/s, cr-PWV was 6.9±0.9 m/s, PWVr was 0.75±0.12. PWVr exhibited a linear increase across increasing quartiles of sMSTN (0.71±0.1, 0.74±0.1, 0.7±0.1, 0.77±0.1, p for trend=0.03), whereas the association between sMSTN and each single component of PWVr (cf-PWV, cr-PWV) did not attain statistical significance. Quartiles of sMSTN displayed a positive trend with serum HDL-cholesterol (p=0.01) and a negative one with LDL-cholesterol (p=0.01). In a multivariate linear model, the association between PWVr and sMSTN was independent from SBP values, age, sex, heart rate, BMI, HDL-cholesterol and HOMA Index. CONCLUSIONS: In healthy adolescents, sMSTN showed independent associations with PWVr, a measure of central-to-peripheral arterial stiffness gradient. sMSTN may exert differential effects on the structural and functional properties of the arterial wall.

2.
Mol Metab ; 68: 101674, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36657563

RESUMO

OBJECTIVE: Thioalbamide is a ribosomally synthesized and post-translationally modified peptide (RiPP) belonging to the family of thioamitides, a rare class of microbial specialized metabolites with unusual post-translational modifications and promising biological activities. Recent studies have demonstrated the ability of thioalbamide to exert highly selective cytotoxic effects on tumor cells by affecting their energy metabolism, thus causing abnormal ROS production and triggering apoptosis. This study is aimed to investigate the molecular mechanisms underlying the antitumor activity of thioalbamide in order to identify its exact molecular target. METHODS: Wild type MCF-7 and MDA-MB-231 breast cancer cell lines as well as cancer cells deprived of mitochondrial DNA (ρ0 cells) were employed in order to assess thioalbamide effects on tumor bioenergetics. In this regard, metabolic profile was evaluated by a Seahorse XFe96 analyzer, and the activity of the enzyme complexes involved in oxidative phosphorylation was quantified by spectrophotometric assays. Thioalbamide effects on tumor invasiveness were assessed by gelatin zymography experiments and invasion assays. In vivo experiments were carried out on breast cancer xenograft and "experimental metastasis" mouse models. RESULTS: Experiments carried out on ρ0 breast cancer cells, together with Seahorse analysis and the application of spectrophotometric enzymatic assays, highlighted the ability of thioalbamide to affect the mitochondrial respiration process, and allowed to propose the FoF1-ATPase complex as its main molecular target in breast cancer cells. Additionally, thioalbamide-mediated OXPHOS inhibition was shown, for the first time, to reduce tumor invasiveness by inhibiting metalloproteinase-9 secretion. Furthermore, this study has confirmed the antitumor potential of thioalbamide in two different in vivo models. In particular, experiments on MCF-7 and MDA-MB-231 xenograft mouse models have confirmed in vivo its high anti-proliferative and pro-apoptotic activity, while experiments on MDA-MB-231 ″experimental metastasis" mouse models have highlighted its ability to inhibit breast cancer cell invasiveness. CONCLUSIONS: Overall, our results shed more light on the molecular mechanisms underlying the pharmacological potential of thioamidated peptides, thus reducing the gap that separates this rare class of microbial metabolites from clinical studies, which could validate them as effective tools for cancer treatment.


Assuntos
Antineoplásicos , Neoplasias da Mama , ATPases Translocadoras de Prótons , Animais , Feminino , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Invasividade Neoplásica , Peptídeos/farmacologia , ATPases Translocadoras de Prótons/antagonistas & inibidores
3.
Mini Rev Med Chem ; 16(8): 619-29, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26156545

RESUMO

Elevated serum cholesterol, triglycerides and LDL levels are often associated with an increased incidence of atherosclerosis and coronary artery disease. The most effective therapeutic strategy against these diseases is based on statins administration, nevertheless some patients, especially those with metabolic syndrome fail to achieve their recommended LDL targets with statin therapy, moreover, it may induce many serious side effects. Several scientific studies have highlighted a strong correlation between diets rich in flavonoids and cardiovascular risk reduction. In particular, Citrus bergamia Risso, also known as bergamot, has shown a significant degree of hypocholesterolemic and antioxidant/radical scavenging activities. In addition, this fruit has attracted considerable attention due to its peculiar flavonoid composition, since it contains some flavanones that can act as natural statins. Hence, the study of bergamot flavonoids as metabolic regulators offers a great opportunity for screening and discovery of new therapeutic agents. Cholesterol metabolism, flavonoid composition and potential therapeutic use of C. bergamia Risso will be discussed in the following review.


Assuntos
Aterosclerose/tratamento farmacológico , Citrus/química , Flavonoides/uso terapêutico , Hiperlipidemias/tratamento farmacológico , Animais , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular
4.
Anal Bioanal Chem ; 398(5): 2163-71, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20835864

RESUMO

An automated in-capillary assay requiring very small quantities of reagents was developed for performing in vitro cytochrome P450 (CYP450) drug metabolism studies. The approach is based on the following: (i) hydrodynamic introduction of nanoliter volumes of substrate and enzyme solutions in the sandwich mode, within a capillary; (ii) mixing the reagents by diffusion across the interfaces between the injected solutions; (iii) collection of the capillary content at the end of the in-capillary assay; and (iv) off-line analysis of the incubation mixture by ultrahigh pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). After optimizing the injection sequence of the reagents, the in-capillary approach was applied to the quantitative determination of the kinetics of drug metabolism reactions catalyzed by three CYP450 isozymes involved in human drug metabolism: CYP1A2, CYP2D6, and CYP3A4. It was demonstrated that this in-capillary method was able to provide similar kinetic parameters for CYP450 activity (e.g., Michaelis constants and turnover values) as the classical in vitro method, with a drastic reduction of reagent consumption.


Assuntos
Bioensaio/métodos , Sistema Enzimático do Citocromo P-450/análise , Cromatografia Líquida/métodos , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos , Cinética , Espectrometria de Massas
5.
J Mol Biol ; 357(4): 1306-21, 2006 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-16483608

RESUMO

A novel computational approach to the structural analysis of ordered beta-aggregation is presented and validated on three known amyloidogenic polypeptides. The strategy is based on the decomposition of the sequence into overlapping stretches and equilibrium implicit solvent molecular dynamics (MD) simulations of an oligomeric system for each stretch. The structural stability of the in-register parallel aggregates sampled in the implicit solvent runs is further evaluated using explicit water simulations for a subset of the stretches. The beta-aggregation propensity along the sequence of the Alzheimer's amyloid-beta peptide (Abeta(42)) is found to be highly heterogeneous with a maximum in the segment V(12)HHQKLVFFAE(22) and minima at S(8)G(9), G(25)S(26), G(29)A(30), and G(38)V(39), which are turn-like segments. The simulation results suggest that these sites may play a crucial role in determining the aggregation tendency and the fibrillar structure of Abeta(42). Similar findings are obtained for the human amylin, a 37-residue peptide that displays a maximal beta-aggregation propensity at Q(10)RLANFLVHSSNN(22) and two turn-like sites at G(24)A(25) and G(33)S(34). In the third application, the MD approach is used to identify beta-aggregation "hot-spots" within the N-terminal domain of the yeast prion Ure2p (Ure2p(1-94)) and to design a double-point mutant (Ure2p-N4748S(1-94)) with lower beta-aggregation propensity. The change in the aggregation propensity of Ure2p-N4748S(1-94) is verified in vitro using the thioflavin T binding assay.


Assuntos
Peptídeos beta-Amiloides/química , Amiloide/química , Simulação por Computador , Fragmentos de Peptídeos/química , Príons/química , Estrutura Secundária de Proteína , Proteínas de Saccharomyces cerevisiae/química , Sequência de Aminoácidos , Amiloide/genética , Amiloide/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glutationa Peroxidase , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Mutação Puntual , Príons/genética , Príons/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência
6.
Rev. bras. implantodontia ; 9(1): 5-6, jan.-mar. 2003. ilus
Artigo em Português | BBO - Odontologia | ID: biblio-857323

RESUMO

Pacientes com câncer avançado de cavidade oral estádios III e IV evoluem com prognóstico sombrio, porém não são excluídos de necessidade de reabilitação. Relatamos o caso de paciente que apresentou tumor primário de língua extenso tratado com glossectomia total e radioterapia pós-operatória e que, quatro anos após tratamento, desenvolveu uma segunda lesão em palato duro, tratado com radioterapia e resgate cirúrgico com ressecção total da infraestrutura do maxilar. Apesar do prognóstico reservado, o paciente foi reabilitado com implantes osseointegrados e prótese com sucesso, mesmo após a radioterapia


Assuntos
Neoplasias Bucais , Osseointegração , Palato , Neoplasias da Língua
7.
Healthc Financ Manage ; 42(9): 62-4, 66, 68 passim, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10312677

RESUMO

Nursing care is a very significant part of a healthcare organization's costs. However, until recently, methods of controlling nursing costs were largely ineffective. With the implementation of the prospective payment system and the use of diagnosis related groups, budgeting and controlling nursing costs are now possible with the use of standard costing. In this article, methods and procedures are discussed and explained for controlling inpatient nursing costs with the use of DRGs and standard costs.


Assuntos
Contabilidade/métodos , Grupos Diagnósticos Relacionados/economia , Serviço Hospitalar de Enfermagem/economia , Gestão de Recursos Humanos/economia , Admissão e Escalonamento de Pessoal/economia , Análise de Variância , Orçamentos , Controle de Custos/métodos , Custos e Análise de Custo , Tempo de Internação/economia , Estados Unidos
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