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2.
Nat Cell Biol ; 23(12): 1224-1239, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34876685

RESUMO

Defective silencing of retrotransposable elements has been linked to inflammageing, cancer and autoimmune diseases. However, the underlying mechanisms are only partially understood. Here we implicate the histone H3.3 chaperone Daxx, a retrotransposable element repressor inactivated in myeloid leukaemia and other neoplasms, in protection from inflammatory disease. Loss of Daxx alters the chromatin landscape, H3.3 distribution and histone marks of haematopoietic progenitors, leading to engagement of a Pu.1-dependent transcriptional programme for myelopoiesis at the expense of B-cell differentiation. This causes neutrophilia and inflammation, predisposing mice to develop an autoinflammatory skin disease. While these molecular and phenotypic perturbations are in part reverted in animals lacking both Pu.1 and Daxx, haematopoietic progenitors in these mice show unique chromatin and transcriptome alterations, suggesting an interaction between these two pathways. Overall, our findings implicate retrotransposable element silencing in haematopoiesis and suggest a cross-talk between the H3.3 loading machinery and the pioneer transcription factor Pu.1.


Assuntos
Cromatina/patologia , Proteínas Correpressoras/genética , Transtornos Leucocíticos/congênito , Chaperonas Moleculares/genética , Mielopoese/genética , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/patologia , Linfócitos B/citologia , Linhagem Celular , Cromatina/genética , Células-Tronco Hematopoéticas/citologia , Histonas/metabolismo , Humanos , Inflamação/patologia , Transtornos Leucocíticos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Retroelementos/genética , Dermatopatias/genética , Dermatopatias/imunologia , Dermatopatias/patologia
3.
Cell Death Discov ; 4: 2, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29531799

RESUMO

Impaired mitochondrial energy metabolism contributes to a wide range of pathologic conditions, including neurodegenerative diseases. Mitochondrial apoptosis-inducing factor (AIF) is required for the correct maintenance of mitochondrial electron transport chain. An emerging body of clinical evidence indicates that several mutations in the AIFM1 gene are causally linked to severe forms of mitochondrial disorders. Here we investigate the consequence of WAH-1/AIF deficiency in the survival of the nematode Caenorhabditis elegans. Moreover, we assess the survival of C. elegans strains expressing a disease-associated WAH-1/AIF variant. We demonstrate that wah-1 downregulation compromises the function of the oxidative phosphorylation system and reduces C. elegans lifespan. Notably, the loss of respiratory subunits induces a nuclear-encoded mitochondrial stress response independently of an evident increase of oxidative stress. Overall, our data pinpoint an evolutionarily conserved role of WAH-1/AIF in the maintenance of proper mitochondrial activity.

4.
Sci Rep ; 7(1): 17055, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29213114

RESUMO

Chromatin remodelers have emerged as prominent regulators of epigenetic processes and potential drivers of various human pathologies. The multi-subunit chromatin-remodeling SWI/SNF complex determines gene expression programs and, consequently, contributes to the differentiation, maturation and plasticity of neurons. Here, we investigate the elusive biological function of Bcl7a and Bcl7b, two newly identified subunits of the SWI/SNF complex that are highly expressed throughout the brain. We generated ubiquitous and neuron-specific Bcl7a and Bcl7b single and double knockout mice. We provide evidence that Bcl7b is dispensable for animal survival as well as behavioral plasticity. Conversely, ubiquitous Bcl7a knockout results in perinatal lethality, while genetic deletion of Bcl7a in postmitotic neurons elicits motor abnormalities and affects dendritic branching of Purkinje cells, with no obvious synergistic relationship with Bcl7b. Collectively, our findings reveal novel insights into the cellular processes linked to BCL7-containing SWI/SNF complexes and their unrecognized roles in the brain.


Assuntos
Comportamento Animal/fisiologia , Proteínas dos Microfilamentos/metabolismo , Animais , Peso Corporal , Encéfalo/metabolismo , Células Cultivadas , Feminino , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/deficiência , Proteínas dos Microfilamentos/genética , Subunidades Proteicas/deficiência , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Células de Purkinje/citologia , Células de Purkinje/metabolismo
5.
J Neurol Sci ; 383: 166-168, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29246607

RESUMO

BACKGROUND: Patients' walking ability is critical for assessing the EDSS, the disability scale commonly used in MS clinical practice. Such assessment is usually based on patients' estimates or on the measures the neurologists observe during periodic visits. OBJECTIVES AND METHODS: We evaluated the agreement between patients' and neurologists' estimates of maximum walking ability and patients' mean maximum walking ability measured in their daily life through a GPS smartwatch, and assessed limitations of the current methods. RESULTS: Seventy-three patients with a median walking ability of 500m (IQR 400-800) were enrolled in the study. The agreement between patients' estimates and GPS measurements was modest (ICC 0.29, 95% CIs 0.06-0.49) and was influenced by course of the disease, patients' mood and inaccuracy at estimating long distances. A better reliability was found between neurologists' and GPS measures (ICC 0.68, 95% CIs 0.53-0.78), but the variability increased for longer distances and was influenced by patients' depressive symptoms, fatigue and course of the disease. CONCLUSIONS: This study showed a poor agreement between patients' and neurologists' estimates of maximum walking ability and patients' mean maximum walking ability measured in their daily life through a GPS smartwatch, with many factors affecting patient's and neurologists' estimates of the EDSS. The use of remote measurement technologies may provide a better understanding of the impact of MS in a patient's life.


Assuntos
Computadores de Mão , Diagnóstico por Computador/instrumentação , Avaliação da Deficiência , Esclerose Múltipla/diagnóstico , Dispositivos Eletrônicos Vestíveis , Actigrafia/instrumentação , Actigrafia/métodos , Atividades Cotidianas , Depressão/complicações , Depressão/diagnóstico , Depressão/fisiopatologia , Diagnóstico por Computador/métodos , Progressão da Doença , Fadiga/complicações , Fadiga/diagnóstico , Fadiga/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/fisiopatologia , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Prospectivos , Caminhada , Punho
6.
Clin Trials ; 11(6): 667-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25092808

RESUMO

BACKGROUND: Recruiting patients for randomized clinical trials is still extremely difficult. While there has been much research in oncology patients, no previous studies have consistently addressed specific factors affecting the willingness to enroll in multiple sclerosis trials from the patient's perspective. To this end, we conducted an exploratory study to assess the related factors and to find ways to improve recruitment. METHODS: This is a single-center, observational study involving 352 consecutive outpatients followed at one site in Italy. Patients completed the Enrollment Problems Questionnaire and Beck Depression Inventory. RESULTS: Over 50% of the patients would consider participating in a randomized trial. Willing patients are frequently older, with no children, have a diagnosis of secondary progressive multiple sclerosis, and have already participated in clinical trials. Patients' choices were positively influenced by expectations of having (a) a greater chance of cure, (b) an unavailable drug, (c) a specialist's care, and (d) the chance to contribute to medical research. Willingness was significantly increased by the use of optimistic language and practical/psychological assistance during the decision-making process. CONCLUSION: Multiple sclerosis patients' willingness to participate in a randomized trial is mainly related to both altruistic and individual considerations, as well as to a greater chance of specialist/improved care. More effective information flow and an effective, long-standing patient-physician relationship may improve recruitment overall.


Assuntos
Esclerose Múltipla , Seleção de Pacientes , Pacientes/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Feminino , Humanos , Itália , Masculino , Inquéritos e Questionários
8.
Nat Cell Biol ; 16(8): 812-20, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25064737

RESUMO

Microtubule-targeting chemotherapeutics induce apoptosis in cancer cells by promoting the phosphorylation and degradation of the anti-apoptotic BCL-2 family member MCL1. The signalling cascade linking microtubule disruption to MCL1 degradation remains however to be defined. Here, we establish an in vivo screening strategy in Caenorhabditis elegans to uncover genes involved in chemotherapy-induced apoptosis. Using an RNAi-based screen, we identify three genes required for vincristine-induced apoptosis. We show that the DEP domain protein LET-99 acts upstream of the heterotrimeric G protein alpha subunit GPA-11 to control activation of the stress kinase JNK-1. The human homologue of LET-99, DEPDC1, similarly regulates vincristine-induced cell death by promoting JNK-dependent degradation of the BCL-2 family protein MCL1. Collectively, these data uncover an evolutionarily conserved mediator of anti-tubulin drug-induced apoptosis and suggest that DEPDC1 levels could be an additional determinant for therapy response upstream of MCL1.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Moduladores de Tubulina/farmacologia , Animais , Apoptose/fisiologia , Caenorhabditis elegans/citologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Evolução Molecular , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Genes de Helmintos/efeitos dos fármacos , Células HeLa , Humanos , Sistema de Sinalização das MAP Quinases , Células MCF-7 , Microtúbulos/genética , Microtúbulos/metabolismo , Mutação , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fosforilação/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Interferência de RNA , Proteínas Repressoras/genética , Transdução de Sinais/genética , Vincristina/farmacologia
9.
Brain Behav Immun ; 25(5): 947-56, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20940040

RESUMO

Synaptic dysfunction triggers neuronal damage in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis (MS). While excessive glutamate signaling has been reported in the striatum of EAE, it is still uncertain whether GABA synapses are altered. Electrophysiological recordings showed a reduction of spontaneous GABAergic synaptic currents (sIPSCs) recorded from striatal projection neurons of mice with MOG((35-55))-induced EAE. GABAergic sIPSC deficits started in the acute phase of the disease (20-25days post immunization, dpi), and were exacerbated at later time-points (35, 50, 70 and 90dpi). Of note, in slices they were independent of microglial activation and of release of TNF-α. Indeed, sIPSC inhibition likely involved synaptic inputs arising from GABAergic interneurons, because EAE preferentially reduced sIPSCs of high amplitude, and was associated with a selective loss of striatal parvalbumin (PV)-positive GABAergic interneurons, which contact striatal projection neurons in their somatic region, giving rise to more efficient synaptic inhibition. Furthermore, we found also that the chronic persistence of pro-inflammatory cytokines were able, per se, to produce profound alterations of electrophysiological network properties, that were reverted by GABA administration. The results of the present investigation indicate defective GABA transmission in MS models depending from alteration of PV cells number and, in part, deriving from the effects of a chronic inflammation, and suggest that pharmacological agents potentiating GABA signaling might be considered to limit neuronal damage in MS patients.


Assuntos
Corpo Estriado/fisiopatologia , Encefalomielite Autoimune Experimental/fisiopatologia , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/fisiologia , Animais , Western Blotting , Células Cultivadas , Corpo Estriado/metabolismo , Citocinas/fisiologia , Encefalomielite Autoimune Experimental/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/fisiologia
10.
Int J Surg ; 8(3): 216-20, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20184969

RESUMO

INTRODUCTION: Endograft infection has received less attention than other complication, so that little is known about the general features, risk factors, and treatment. The purpose of this short series is to examine our experience of infective complications after EVAR. MATERIAL AND METHODS: Between November 2000 and December 2008, 247 patients underwent endograft repair for abdominal aortic aneurysm. Follow-up protocol included clinical visit and computed-tomography angiography 1, 4 and 12 months after the intervention, and yearly thereafter. No duplex control was performed on a regular basis. RESULTS: Median follow-up was 16 months (range, 3-92); two patients (2/244, 0.8%) developed an endograft infection, 12 and 36-months after the intervention respectively. On admission, both patients complained septic-like fever and abdominal discomfort; leukocytes-labelled scans did not reveal pathologic traits whereas spiral computed-tomography confirmed the suspicious of endograft infection. They underwent endograft removal and extra-anatomic axillo-bifemoral by-pass; both survived and are still alive 12 and 6-months after the intervention. Isolated micro-organisms were Candida albicans and Escherichia coli in one patient, and Haemophilus aphrophilus in the other. CONCLUSION: Endograft infection is an uncommon occurrence, Spiral computed-tomography seems to be an essential diagnostic tool. Graft removal was successful in our high-risk patients. A multicenter registry should be started to define guidelines.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Prótese Vascular/efeitos adversos , Infecções Relacionadas à Prótese , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/terapia , Stents
11.
Int Rev Neurobiol ; 85: 389-405, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19607983

RESUMO

The effects of bergamot essential oil (BEO; Citrus bergamia, Risso) on brain damage caused by permanent focal cerebral ischemia in rat were investigated. Administration of BEO (0.1-0.5 ml/kg but not 1 ml/kg, given intraperitoneally 1 h before occlusion of the middle cerebral artery, MCAo) significantly reduced infarct size after 24 h permanent MCAo. The most effective dose (0.5 ml/kg) resulted in a significant reduction of infarct extension throughout the brain, especially in the medial striatum and the motor cortex as revealed by TTC staining of tissue slices. Microdialysis experiments show that BEO (0.5 ml/kg) did not affect basal amino acid levels, whereas it significantly reduced excitatory amino acid, namely aspartate and glutamate, efflux in the frontoparietal cortex typically observed following MCAo. Western blotting experiments demonstrated that these early effects were associated, 24 h after permanent MCAo, to a significant increase in the phosphorylation and activity of the prosurvival kinase, Akt. Indeed, BEO significantly enhanced the phosphorylation of the deleterious downstream kinase, GSK-3beta, whose activity is negatively regulated via phosphorylation by Akt.


Assuntos
Infarto Encefálico/prevenção & controle , Isquemia Encefálica/fisiopatologia , Ácido Glutâmico/biossíntese , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Óleos Voláteis/uso terapêutico , Óleos de Plantas/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/biossíntese , Animais , Isquemia Encefálica/tratamento farmacológico , Masculino , Ratos , Ratos Wistar , Regulação para Cima/efeitos dos fármacos
12.
Int J Surg ; 6 Suppl 1: S75-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19129014

RESUMO

Diabetic foot is complex and difficult to treat. More aggressive treatment using peripheral distal by-pass frequently combined to minor amputations has greatly improved limb salvage in most patients. However, diabetes-related amputations are at high risk of non-healing or superinfection, thus requiring a second-step surgical revision treatment more frequently than in non-diabetic patients. Several advanced technologies have been developed to improve the treatment of diabetic foot wounds including Vacuum Assisted Therapy: we present 3 cases of diabetic patients treated with preliminary surgical peripheral revascularization, subsequent minor amputation in combination with Vacuum Assisted Therapy performed in a day-surgery regime.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/métodos , Amputação Cirúrgica/métodos , Pé Diabético/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia , Pé Diabético/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia Doppler
13.
Am J Surg ; 193(4): 443-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17368285

RESUMO

OBJECTIVES: To report our mid-term results of stent-graft (SG) placement for the treatment of penetrating thoracic aortic ulcers. METHODS: In the last 30 months, 11 patients (9 men; mean age 73 years; range 55 to 81) were treated for 12 penetrating thoracic aortic ulcers using SGs. Five patients were symptomatic: 2 had ruptured ulcers and 2 cases were complicated with dissection. Mean European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 10. Three patients had concomitant endovascular repair for an infrarenal abdominal aortic aneurysm (AAA). Follow-up included periodic computed tomography angiography (CT-A) scans at 1, 4, and 12 months after the intervention, and yearly thereafter. RESULTS: Primary technical success was achieved in 100% of patients; no conversion was required. In-hospital mortality did not occur. Paraplegia was not observed. Mean follow-up was 15 months (range 2 to 36). One patient died of respiratory failure 2 months after the intervention. Radiologic follow-up did not detect endoleaks. Survival was 90% at 1 and 3 years. CONCLUSIONS: Our experience confirms the feasibility of SG treatment for elective and urgent repair of penetrating aortic ulcers. Our current attitude is to treat all the ulcers of the descending aorta using an endovascular technique, since SG treatment represents a good treatment option, as the morbidity and mortality are low.


Assuntos
Doenças da Aorta/cirurgia , Implante de Prótese Vascular , Stents , Úlcera/cirurgia , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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