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1.
Cell Rep ; 42(2): 112104, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36787220

RESUMO

Microglia reactivity entails a large-scale remodeling of cellular geometry, but the behavior of the microtubule cytoskeleton during these changes remains unexplored. Here we show that activated microglia provide an example of microtubule reorganization from a non-centrosomal array of parallel and stable microtubules to a radial array of more dynamic microtubules. While in the homeostatic state, microglia nucleate microtubules at Golgi outposts, and activating signaling induces recruitment of nucleating material nearby the centrosome, a process inhibited by microtubule stabilization. Our results demonstrate that a hallmark of microglia reactivity is a striking remodeling of the microtubule cytoskeleton and suggest that while pericentrosomal microtubule nucleation may serve as a distinct marker of microglia activation, inhibition of microtubule dynamics may provide a different strategy to reduce microglia reactivity in inflammatory disease.


Assuntos
Microglia , Microtúbulos , Centrossomo , Citoesqueleto , Complexo de Golgi , Tubulina (Proteína)
2.
Nutrients ; 15(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36615882

RESUMO

In 2010, the Mediterranean diet was recognized by UNESCO as an Intangible Cultural Heritage of Humanity. Olive oil is the most characteristic food of this diet due to its high nutraceutical value. The positive effects of olive oil have often been attributed to its minor components; however, its oleic acid (OA) content (70-80%) is responsible for its many health properties. OA is an effective biomolecule, although the mechanism by which OA mediates beneficial physiological effects is not fully understood. OA influences cell membrane fluidity, receptors, intracellular signaling pathways, and gene expression. OA may directly regulate both the synthesis and activities of antioxidant enzymes. The anti-inflammatory effect may be related to the inhibition of proinflammatory cytokines and the activation of anti-inflammatory ones. The best-characterized mechanism highlights OA as a natural activator of sirtuin 1 (SIRT1). Oleoylethanolamide (OEA), derived from OA, is an endogenous ligand of the peroxisome proliferator-activated receptor alpha (PPARα) nuclear receptor. OEA regulates dietary fat intake and energy homeostasis and has therefore been suggested to be a potential therapeutic agent for the treatment of obesity. OEA has anti-inflammatory and antioxidant effects. The beneficial effects of olive oil may be related to the actions of OEA. New evidence suggests that oleic acid may influence epigenetic mechanisms, opening a new avenue in the exploration of therapies based on these mechanisms. OA can exert beneficial anti-inflammatory effects by regulating microRNA expression. In this review, we examine the cellular reactions and intracellular processes triggered by OA in T cells, macrophages, and neutrophils in order to better understand the immune modulation exerted by OA.


Assuntos
Dieta Mediterrânea , Ácido Oleico , Ácido Oleico/farmacologia , Ácido Oleico/uso terapêutico , Azeite de Oliva/farmacologia , Ácidos Oleicos/farmacologia , Anti-Inflamatórios/farmacologia
3.
Cells ; 11(17)2022 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-36078082

RESUMO

BACKGROUND: Sorafenib constitutes a suitable treatment alternative for patients with advanced hepatocellular carcinoma (HCC) in whom atezolizumab + bevacizumab therapy is contraindicated. The aim of the study was the identification of a miRNA signature in liquid biopsy related to sorafenib response. METHODS: miRNAs were profiled in hepatoblastoma HepG2 cells and tested in animal models, extracellular vesicles (EVs), and plasma from HCC patients. RESULTS: Sorafenib altered the expression of 11 miRNAs in HepG2 cells. miR-200c-3p and miR-27a-3p exerted an anti-tumoral activity by decreasing cell migration and invasion, whereas miR-122-5p, miR-148b-3p, miR-194-5p, miR-222-5p, and miR-512-3p exerted pro-tumoral properties by increasing cell proliferation, migration, or invasion, or decreasing apoptosis. Sorafenib induced a change in EVs population with an increased number of larger EVs, and promoted an accumulation of miR-27a-3p, miR-122-5p, miR-148b-3p, miR-193b-3p, miR-194-5p, miR-200c-3p, and miR-375 into exosomes. In HCC patients, circulating miR-200c-3p baseline levels were associated with increased survival, whereas high levels of miR-222-5p and miR-512-3p after 1 month of sorafenib treatment were related to poor prognosis. The RNA sequencing revealed that miR-200c-3p was related to the regulation of cell growth and death, whereas miR-222-5p and miR-512-3p were related to metabolic control. CONCLUSIONS: The study showed that Sorafenib regulates a specific miRNA signature in which miR-200c-3p, miR-222-5p, and miR-512-3p bear prognostic value and contribute to treatment response.


Assuntos
Carcinoma Hepatocelular , MicroRNAs , Sorafenibe , Biomarcadores , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico
4.
Angiogenesis ; 24(1): 13-15, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33052496

RESUMO

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal-dominant disease characterized by pathologic angiogenesis that provokes vascular overgrowth. The evidence about the influence of Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) in patients with rare diseases is scarce. We aimed to know the prevalence of coronavirus disease 2019 (COVID-19) in HHT patients. The HHT pathogenic angiogenesis and endothelial injury in COVID-19 are discussed using data from RiHHTa (Computerized Registry of Hereditary Hemorrhagic Telangiectasia) registry. RiHHTa is an open, multicenter, prospective, observational registry including adult patients with HHT. A 27-item survey that captured clinical data of admitted HHT patients for COVID-19 was distributed to all RiHHTa investigators from June 8th to June 24th 2020. Only one out of 1177 HHT patients was admitted for COVID-19 pneumonia. She is a 74 years-old woman with a pathogenic variant in ACVRL1 gene. Her clinical course did not involve mechanical ventilation or worsening epistaxis, and she was successfully discharged after two weeks. The endothelial damage and the consequent angiogenic process in COVID-19 patients deserve further investigation.


Assuntos
Receptores de Activinas Tipo II/genética , COVID-19/complicações , COVID-19/epidemiologia , Neovascularização Patológica , Telangiectasia Hemorrágica Hereditária/complicações , Telangiectasia Hemorrágica Hereditária/epidemiologia , Idoso , Feminino , Humanos , Admissão do Paciente , Prevalência , Estudos Prospectivos , Sistema de Registros , Espanha , Inquéritos e Questionários
5.
Rev Esp Geriatr Gerontol ; 55(1): 3-10, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-31585682

RESUMO

BACKGROUNDS AND OBJECTIVES: The use of physical restraints (PR) is common in the care of the elderly. However, their efficacy and safety are not supported by scientific evidence. The aim of this study was to determine the role of PR in preventing falls. MATERIALS AND METHODS: A retrospective cohort study design was used, in which each fall incident (n=575) was examined in the residents over 65 years of age who resided at the one nursing homes from February 2009 to September 2013. An analysis was made of the association between the use of PR and risk of falls using a multivariate logistic regression, adjusting for the characteristics of residents that were associated with the use of PR according to a bivariate analysis. RESULTS: Risk factors for falls after accounting for PR use, include: risk of falling (Tinetti test) (OR 4.57; 95% CI 1.76-11.75); ability to walk (OR 6.40; 95% CI 2.78-14.74); hearing impairment (OR 2.12; 95% CI 1.05-4.29); and history of a previous fall (OR 17.81; 95% CI 8.83-35.93). The risk of falls was greater in restrained, ambulatory residents with cognitive impairment (OR 18.95; 95% CI 7.06-50.85). No differences were found in injuries between falls that occurred with and without PR. CONCLUSIONS: Restraint use was not significantly associated with fewer falls and injuries. The risk of falls could increase in ambulatory residents with cognitive impairment. The study results suggest the need to consider whether restraints provide adequate protection against the risk of falls.


Assuntos
Acidentes por Quedas/prevenção & controle , Transtornos Cognitivos/complicações , Instituição de Longa Permanência para Idosos , Casas de Saúde , Restrição Física , Acidentes por Quedas/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Modelos Logísticos , Masculino , Restrição Física/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Caminhada
6.
Rev. argent. mastología ; 38(140): 19-33, dic. 2019.
Artigo em Espanhol | LILACS | ID: biblio-1116264

RESUMO

Objetivo Analizar las publicaciones relacionadas con los factores asociados a la reincorporación laboral posterior al tratamiento de las pacientes con cáncer de mama. Material y método Se realizó una revisión sistemática en la literatura científica en PubMed, ScienceDirect, Cochrane y LILACS de artículos observacionales que, en los últimos cinco años (julio de 2013 a julio de 2018), evaluaran la prevalencia, barreras y facilitadores para el retorno al trabajo de las pacientes con cáncer de mama. Resultados Se incluyeron 19 artículos que evalúan el retorno al trabajo de la paciente con cáncer de mama. La prevalencia de reincorporación laboral osciló entre el 32% y el 82%. Los principales aspectos facilitadores identificados fueron: el nivel educativo alto, el estado civil soltera, los altos ingresos y el apoyo en el lugar de trabajo. Por el contrario, el hecho de recibir quimioterapia, la fatiga, la presencia de comorbilidades y una edad avanzada se comportan como barreras para el regreso al trabajo. Conclusiones Un mayor entendimiento de las barreras y facilitadores del retorno al ámbito laboral podría mejorar el porcentaje de pacientes que regresan a trabajar y mejorar sus condiciones en el lugar donde desempeñan sus labores


Objective To analyse the publications related to the factors associated with the labour reincorporation after treatment of patients with breast cancer. Materials and method A systematic review of the scientific literature was performed in PubMed, ScienceDirect, Cochrane and LILACS of observational articles which evaluated the prevalence, barriers and facilitators for the return to work of patients with breast cancer, in the last five years (July 2013-July 2018). Results 19 articles evaluating the return to work of the patient with breast cancer were included. The prevalence of labour reincorporation ranged between 32% and 82%- The main facilitating aspects identified were: high educational level, single marital status, high income and support in the workplace. On the contrary, the fact of receiving chemotherapy, fatigue, the presence of comorbidities and advanced age behave as barriers to return to work. Conclusions A better understanding of the barriers and facilitators of this process could improve the percentage of patients who return to work and improve their conditions in the workplace


Assuntos
Trabalho , Neoplasias da Mama , Retorno ao Trabalho
7.
Syst Rev ; 8(1): 146, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221217

RESUMO

BACKGROUND: Ocular toxoplasmosis (OT) is the most common cause of posterior uveitis, leading to visual impairment in a high proportion of patients. Antibiotics and corticosteroids lower the risk of permanent visual impairment by reducing the size of the retinochoroidal scar, the risk of recurrence, and the severity and duration of acute symptoms. Although OT is a very common cause of infectious posterior uveitis, its treatment remains controversial. Through our systematic review and meta-analysis, we aim to provide the best possible evidence-based information on the safety and effectiveness of the different antibiotic regimes for OT. METHODS: This systematic review protocol has been developed based on PRISMA-P guidelines for reporting systematic reviews evaluating health care interventions. We will include all published and unpublished randomized controlled trials (RCTs) comparing different antibiotics used for the treatment of OT. We will consider changes in visual acuity, number of recurrences, improvement or worsening of ocular inflammation, size of lesion, and adverse effects as our outcomes. Screening, data extraction, and quality assessment will be undertaken by two reviewers with disagreements resolved through discussion. Studies that compared antibiotics with placebo will be excluded. The reviews will be assessed for quality and relevance. We will assess the risk of bias in five domains according to Cochrane group's tool. The type of data will dictate measures of treatment effect. We will use a random-effects model to calculate our meta-analysis, as eligible studies represent clinically varied populations of participants. DISCUSSION: The strength of our study will lie in the exhaustive and systematic nature of the literature search, as well as in its methods for assessing quality and analyzing RCT data. Considering the controversial efficacy of the treatment for OT, our study will contribute to improving the existing evidence on the effectiveness of different antibiotics. Future studies may be conducted to increase physicians' awareness of antibiotic therapies, improving the health of patients with OT. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018085468.


Assuntos
Antibacterianos , Antiprotozoários , Toxoplasmose Ocular , Humanos , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Antiprotozoários/efeitos adversos , Antiprotozoários/uso terapêutico , Toxoplasma/efeitos dos fármacos , Toxoplasmose Ocular/tratamento farmacológico , Resultado do Tratamento , Metanálise como Assunto , Revisões Sistemáticas como Assunto
8.
J Theor Biol ; 245(1): 175-92, 2007 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-17081569

RESUMO

In the present paper, a kinetic analysis of a general model for proenzyme activation, where the activating enzyme and also the activated one are reversibly inhibited in two steps by two different inhibitors, has been performed. The cases in which both inhibitors are the same, or in which the inhibition is irreversible (only one or the two inhibition routes) are treated as particular cases of the general model. In addition, the kinetic behaviour of many other proenzyme activation systems involving inhibition, particular cases of the reaction scheme under study, can be obtained. The total number of particular cases for the general model under study is 370, so this approach offers to the scientific community working in limited proteolysis regulation for the first time a method based on general solutions which only needs to be specified to their concrete problem of zymogen activation. Finally, new adimensional parameters are introduced, allowing the knowledgement, in the case that any of the inhibition routes is irreversible, the relative weight of both activation and irreversible inhibition routes.


Assuntos
Inibidores Enzimáticos/metabolismo , Precursores Enzimáticos/metabolismo , Animais , Ativação Enzimática , Precursores Enzimáticos/antagonistas & inibidores , Matemática , Modelos Químicos , Peptídeo Hidrolases/metabolismo , Fatores de Tempo
9.
Acta Biochim Pol ; 53(2): 407-20, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16770446

RESUMO

Taking as the starting point a recently suggested reaction scheme for zymogen activation involving intra- and intermolecular routes and the enzyme-zymogen complex, we carry out a complete analysis of the relative contribution of both routes in the process. This analysis suggests the definition of new dimensionless parameters allowing the elaboration, from the values of the rate constants and initial conditions, of the time course of the contribution of the two routes. The procedure mentioned above related to a concrete reaction scheme is extrapolated to any other model of autocatalytic zymogen activation involving intra- and intermolecular routes. Finally, we discuss the contribution of both of the activating routes in pepsinogen activation into pepsin using the values of the kinetic parameters given in the literature.


Assuntos
Algoritmos , Precursores Enzimáticos/metabolismo , Pepsinogênio A/metabolismo , Catálise , Ativação Enzimática , Precursores Enzimáticos/química , Cinética , Modelos Químicos , Pepsinogênio A/química
10.
Biol Chem ; 386(7): 689-98, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16207090

RESUMO

A kinetic study was performed of a model for an autocatalytic zymogen activation process involving both intra- and intermolecular routes, to which a chromogenic reaction in which the active enzyme acts upon one of its substrates was coupled to continuously monitor the reaction. Kinetic equations describing the evolution of species involved in the system with time were obtained. These equations are valid for any zymogen autocatalytic activation process under the same initial conditions. Experimental design and kinetic data analysis procedures to evaluate the kinetic parameters, based on the derived kinetic equations, are suggested. In addition, a dimensionless distribution coefficient was defined, which shows mathematically whether the intra- or the intermolecular route prevails once the kinetic parameters involved in the system are known. The validity of the results obtained was checked using simulated curves for the species involved. As an example of application of the method, the system is experimentally illustrated by the continuous monitoring of pepsinogen transformation to pepsin.


Assuntos
Precursores Enzimáticos/metabolismo , Pepsinogênio A/metabolismo , Ativação Enzimática , Cinética
11.
Acta Biochim Pol ; 52(4): 765-80, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16086076

RESUMO

This paper presents a kinetic analysis of the whole reaction course, i.e. of both the transient phase and the steady state, of open multicyclic enzyme cascade systems. Equations for fractional modifications are obtained which are valid for the whole reaction course. The steady state expressions for the fractional modifications were derived from the latter equations since they are not restricted to the condition of rapid equilibrium. Finally, the validity of our results is discussed and tested by numerical integration. Apart from the intrinsic value of knowing the kinetic behaviour of any of the species involved in any open multicyclic enzyme cascade, the kinetic analysis presented here can be the basis of future contributions concerning open multicyclic enzyme cascades which require the knowledge of their time course equations (e.g. evaluation of the time needed to reach the steady state, suggestion of kinetic data analysis, etc.), analogous to those already carried out for open bicyclic cascades.


Assuntos
Enzimas/metabolismo , Simulação por Computador , Cinética , Modelos Teóricos , Reprodutibilidade dos Testes
12.
FEBS J ; 272(1): 85-96, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15634334

RESUMO

A mathematical description was made of an autocatalytic zymogen activation mechanism involving both intra- and intermolecular routes. The reversible formation of an active intermediary enzyme-zymogen complex was included in the intermolecular activation route, thus allowing a Michaelis-Menten constant to be defined for the activation of the zymogen towards the active enzyme. Time-concentration equations describing the evolution of the species involved in the system were obtained. In addition, we have derived the corresponding kinetic equations for particular cases of the general model studied. Experimental design and kinetic data analysis procedures to evaluate the kinetic parameters, based on the derived kinetic equations, are suggested. The validity of the results obtained were checked by using simulated progress curves of the species involved. The model is generally good enough to be applied to the experimental kinetic study of the activation of different zymogens of physiological interest. The system is illustrated by following the transformation kinetics of pepsinogen into pepsin.


Assuntos
Precursores Enzimáticos/metabolismo , Pepsinogênio A/metabolismo , Animais , Cinética , Reprodutibilidade dos Testes , Suínos
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