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1.
Proc Natl Acad Sci U S A ; 121(26): e2316438121, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38900799

RESUMO

Phase transitions occurring in nonequilibrium conditions can evolve through high-energy intermediate states inaccessible via equilibrium adiabatic conditions. Because of the subtle nature of such hidden phases, their direct observation is extremely challenging and requires simultaneous visualization of matter at subpicoseconds and subpicometer scales. Here, we show that a magnetite crystal in the vicinity of its metal-to-insulator transition evolves through different hidden states when controlled via energy-tuned ultrashort laser pulses. By directly monitoring magnetite's crystal structure with ultrafast electron diffraction, we found that upon near-infrared (800 nm) excitation, the trimeron charge/orbital ordering pattern is destroyed in favor of a phase-separated state made of cubic-metallic and monoclinic-insulating regions. On the contrary, visible light (400 nm) activates a photodoping charge transfer process that further promotes the long-range order of the trimerons by stabilizing the charge density wave fluctuations, leading to the reinforcement of the monoclinic insulating phase. Our results demonstrate that magnetite's structure can evolve through completely different metastable hidden phases that can be reached long after the initial excitation has relaxed, breaking ground for a protocol to control emergent properties of matter.

2.
Ann Vasc Surg ; 73: 86-96, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33493590

RESUMO

OBJECTIVES: To analyze the outcome of vascular procedures performed in patients with COVID-19 infection during the 2020 pandemic. METHODS: This is a multicenter, prospective observational cohort study. We analyzed data from 75 patients with COVID-19 infection undergoing vascular surgery procedures in 17 hospitals across Spain and Andorra between March and May 2020. The primary end point was 30-day mortality. Clinical Trials registry number NCT04333693. RESULTS: The mean age was 70.9 (45-94) and 58 (77.0%) patients were male. Around 70.7% had postoperative complications, 36.0% of patients experienced respiratory failure, 22.7% acute renal failure, and 22.7% acute respiratory distress syndrome (ARDS). All-cause 30-days mortality rate was 37.3%. Multivariate analysis identified age >65 years (P = 0.009), American Society of Anesthesiologists (ASA) classification IV (P = 0.004), preoperative lymphocyte count <0.6 (×109/L) (P = 0.001) and lactate dehydrogenase (LDH) >500 (UI/L) (P = 0.004), need for invasive ventilation (P = 0.043), postoperative acute renal failure (P = 0.001), ARDS (P = 0.003) and major amputation (P = 0.009) as independent variables associated with mortality. Preoperative coma (P = 0.001), quick Sepsis Related Organ Failure Assessment (qSOFA) score ≥2 (P = 0.043), lymphocytes <0.6 (×109/L) (P = 0.019) leucocytes >11.5 (×109/L) (P = 0.007) and serum ferritin >1800 mg/dL (P = 0.004), bilateral lung infiltrates on thorax computed tomography (P = 0.025), and postoperative acute renal failure (P = 0.009) increased the risk of postoperative ARDS. qSOFA score ≥2 was the only risk factor associated with postoperative sepsis (P = 0.041). CONCLUSIONS: Patients with COVID-19 infection undergoing vascular surgery procedures showed poor 30-days survival. Age >65 years, preoperative lymphocytes <0.6 (x109/L) and LDH >500 (UI/L), and postoperative acute renal failure, ARDS and need for major amputation were identified as prognostic factors of 30-days mortality.


Assuntos
COVID-19/complicações , Complicações Pós-Operatórias/epidemiologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Injúria Renal Aguda/etiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Andorra/epidemiologia , COVID-19/mortalidade , Estudos de Coortes , Feminino , Humanos , L-Lactato Desidrogenase/sangue , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Prognóstico , Síndrome do Desconforto Respiratório/etiologia , Fatores de Risco , Espanha/epidemiologia , Resultado do Tratamento
3.
Cell Mol Life Sci ; 71(8): 1439-52, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24218009

RESUMO

MicroRNAs (miRNAs) are natural, single-stranded, small RNA molecules which subtly control gene expression. Several studies indicate that specific miRNAs can regulate heart function both in development and disease. Despite prevention programs and new therapeutic agents, cardiovascular disease remains the main cause of death in developed countries. The elevated number of heart failure episodes is mostly due to myocardial infarction (MI). An increasing number of studies have been carried out reporting changes in miRNAs gene expression and exploring their role in MI and heart failure. In this review, we furnish a critical analysis of where the frontier of knowledge has arrived in the fields of basic and translational research on miRNAs in cardiac ischemia. We first summarize the basal information on miRNA biology and regulation, especially concentrating on the feedback loops which control cardiac-enriched miRNAs. A focus on the role of miRNAs in the pathogenesis of myocardial ischemia and in the attenuation of injury is presented. Particular attention is given to cardiomyocyte death (apoptosis and necrosis), fibrosis, neovascularization, and heart failure. Then, we address the potential of miR-diagnosis (miRNAs as disease biomarkers) and miR-drugs (miRNAs as therapeutic targets) for cardiac ischemia and heart failure. Finally, we evaluate the use of miRNAs in the emerging field of regenerative medicine.


Assuntos
Retroalimentação Fisiológica/fisiologia , Regulação da Expressão Gênica/genética , Terapia Genética/métodos , MicroRNAs/uso terapêutico , Isquemia Miocárdica/genética , Isquemia Miocárdica/terapia , Miócitos Cardíacos/fisiologia , Apoptose/fisiologia , Humanos , MicroRNAs/genética , Isquemia Miocárdica/fisiopatologia , Necrose/fisiopatologia , Neovascularização Fisiológica/fisiologia , Medicina Regenerativa/tendências
4.
Ann Ig ; 25(1): 83-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23435783

RESUMO

Zoonoses have been and are still considered merely a "veterinary problem". Instead, the understanding of their emergence, re-emergence and persistence is more effectively addressed in the context of a "struggle" between pathogens, animals and man. The expression properties of pathogens are related with three interfaces: human-environment, environment-animal and human-animal. Animals and man can be either reservoirs or vectors of pathogens, while interfaces can amplify the clinical impact in all the species involved. The disease course is similar in animals and humans in terms of infection, clinical approach and control. Thus, this "epidemiological model" may be the key to an "updated" interpretation of infectious diseases involving humans and animals. Control and prevention should be carried out in an interdisciplinary context, without separating the medical and veterinary domains, in light of the fact that the activity of pathogenic microorganisms is not species-dependent. Finally, if human public health and veterinary public health are closely linked, knowledge and information can be pooled and used for mutual benefit.


Assuntos
Doenças Transmissíveis Emergentes , Zoonoses , Animais , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/etiologia , Doenças Transmissíveis Emergentes/prevenção & controle , Humanos , Zoonoses/epidemiologia , Zoonoses/transmissão
5.
Neurologia (Engl Ed) ; 38(6): 419-426, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37120108

RESUMO

OBJECTIVE: This study provides a series of updated, evidence-based recommendations for the management of acute stroke. We aim to lay a foundation for the development of individual centres' internal protocols, serving as a reference for nursing care. METHODS: We review the available evidence on acute stroke care. The most recent national and international guidelines were consulted. Levels of evidence and degrees of recommendation are based on the Oxford Centre for Evidence-Based Medicine classification. RESULTS: The study describes prehospital acute stroke care, the operation of the code stroke protocol, care provided by the stroke team upon the patient's arrival at hospital, reperfusion treatments and their limitations, admission to the stroke unit, nursing care in the stroke unit, and discharge from hospital. CONCLUSIONS: These guidelines provide general, evidence-based recommendations to guide professionals who care for patients with acute stroke. However, limited data are available on some aspects, showing the need for continued research on acute stroke management.


Assuntos
Cuidados de Enfermagem , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/terapia , Hospitalização , Hospitais , Encaminhamento e Consulta
6.
Cell Mol Life Sci ; 68(10): 1703-17, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21327916

RESUMO

Myocardial infarction (MI) is a leading cause of hospitalization worldwide. A recently developed strategy to improve the management of MI is based on the use of growth factors which are able to enhance the intrinsic capacity of the heart to repair itself or regenerate after damage. Among others, hepatocyte growth factor (HGF) has been proposed as a modulator of cardiac repair of damage due to the pleiotropic effects elicited by Met receptor stimulation. In this review we describe the mechanistic basis for autocrine and paracrine protection of HGF in the injured heart. We also analyse the role of HGF/Met in stem cell maintenance and in stem cell therapies for MI. Finally, we summarize the most significant results on the use of HGF in experimental models of heart injury and discuss the potential of the molecule for treating ischaemic heart disease in humans.


Assuntos
Fator de Crescimento de Hepatócito/fisiologia , Infarto do Miocárdio/terapia , Proteínas Proto-Oncogênicas c-met/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Terapia Genética , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/uso terapêutico , Humanos , Infarto do Miocárdio/fisiopatologia , Comunicação Parácrina , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptores de Fatores de Crescimento/genética , Receptores de Fatores de Crescimento/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
8.
Phys Rev Lett ; 104(14): 140403, 2010 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-20481923

RESUMO

We analyze in detail photon production induced by a superluminal refractive-index perturbation in realistic experimental operating conditions. The interaction between the refractive-index perturbation and the quantum vacuum fluctuations of the electromagnetic field leads to the production of photon pairs.

9.
Phys Rev Lett ; 105(20): 203901, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-21231233

RESUMO

Event horizons of astrophysical black holes and gravitational analogues have been predicted to excite the quantum vacuum and give rise to the emission of quanta, known as Hawking radiation. We experimentally create such a gravitational analogue using ultrashort laser pulse filaments and our measurements demonstrate a spontaneous emission of photons that confirms theoretical predictions.

10.
Neurologia (Engl Ed) ; 2020 Nov 02.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33153769

RESUMO

OBJECTIVE: This study provides a series of updated, evidence-based recommendations for the management of acute stroke. We aim to lay a foundation for the development of individual centres' internal protocols, serving as a reference for nursing care. METHODS: We review the available evidence on acute stroke care. The most recent national and international guidelines were consulted. Levels of evidence and degrees of recommendation are based on the Oxford Centre for Evidence-Based Medicine classification. RESULTS: The study describes prehospital acute stroke care, the operation of the code stroke protocol, care provided by the stroke team upon the patient's arrival at hospital, reperfusion treatments and their limitations, admission to the stroke unit, nursing care in the stroke unit, and discharge from hospital. CONCLUSIONS: These guidelines provide general, evidence-based recommendations to guide professionals who care for patients with acute stroke. However, limited data are available on some aspects, showing the need for continued research on acute stroke management.

11.
Vet Rec ; 164(17): 519-23, 2009 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-19395716

RESUMO

Samples of superficial inguinal and bronchial lymph nodes, ileum, tonsil and lung were taken from three to five pigs on each of 61 farms with a clinical history of postweaning multisystemic wasting syndrome (PMWS). The samples were examined histologically and by immunohistochemistry for porcine circovirus type 2 (PCV-2). PMWS was diagnosed in two stages: first, an evaluation of the haematoxylin and eosin-stained sections that identified the cases in which the characteristic PCV-2 cytoplasmic inclusion bodies were apparent, and secondly, a conclusive step in which immunohistochemistry was applied to confirm PMWS in the cases in which there were positive immunohistochemical results that coincided with lesions indicative of PMWS in at least one of the lymphoid and/or lung tissues. The location of PCV-2 in specific lesions (cell depletion in lymphoid organs and interstitial pneumonia) confirmed PMWS in 45 of the 61 farms, 31 of which were also infected with porcine reproductive and respiratory syndrome virus. The lymphoid tissues were more reliable than the lungs for the diagnosis of PMWS, both in individual pigs and in groups of pigs, and farm diagnoses based on a group of pigs were more reliable than diagnoses based on single pigs.


Assuntos
Síndrome Definhante Multissistêmico de Suínos Desmamados/diagnóstico , Animais , Imuno-Histoquímica/veterinária , Itália/epidemiologia , Tecido Linfoide/virologia , Síndrome Definhante Multissistêmico de Suínos Desmamados/epidemiologia , Guias de Prática Clínica como Assunto , Suínos
12.
J Neuroimmunol ; 151(1-2): 55-65, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15145604

RESUMO

Pixantrone is less cardiotoxic and is similarly effective to mitoxantrone (MTX) as an antineoplastic drug. In our study, pixantrone reduced the severity of acute and decreased the relapse rate of chronic relapsing experimental allergic encephalomyelitis (EAE) in rats. A marked and long-lasting decrease in CD3+, CD4+, CD8+ and CD45RA+ blood cells and reduced anti-MBP titers were observed with both pixantrone and MTX. In vitro mitogen- and antigen-induced T-cell proliferation tests of human and rodents cells evidenced that pixantrone was effective at concentrations which can be effectively obtained after i.v. administration in humans. Cardiotoxicity was present only in MTX-treated rats. The effectiveness and the favorable safety profile makes pixantrone a most promising immunosuppressant agent for clinical use in multiple sclerosis (MS).


Assuntos
Encefalomielite Autoimune Experimental/tratamento farmacológico , Imunossupressores/uso terapêutico , Isoquinolinas/uso terapêutico , Linfócitos T/efeitos dos fármacos , Doença Aguda , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Doença Crônica , Feminino , Humanos , Imunossupressores/efeitos adversos , Isoquinolinas/efeitos adversos , Contagem de Linfócitos , Mitoxantrona/efeitos adversos , Mitoxantrona/uso terapêutico , Ratos , Linfócitos T/imunologia
13.
Pathol Res Pract ; 179(1): 95-100, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6504774

RESUMO

Clinical and anatomo-histopathological features of experimental infection by DF-2 in rabbits are described. Hyperthermy, sensory reduction, diarrhoea, weight loss and catarrhal nasal discharge are reported. PTT and PT are shown to increase and number of platelets diminish markedly. Considerable haemorrhagic diathesis is reported for several organs. Several clots (especially in pulmonary vessels), serious alterations in kidney glomeruli, degeneration of hepatocytes and disseminated necrosis foci are also reported. Lesions are stated as being very similar to those observed in man.


Assuntos
Infecções Bacterianas/patologia , Animais , Infecções Bacterianas/sangue , Bactérias Gram-Negativas , Hemostasia , Glomérulos Renais/patologia , Fígado/patologia , Masculino , Coelhos
14.
J Agric Food Chem ; 47(1): 141-4, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10563862

RESUMO

The composition of artificial casein micelles (ACM) prepared at constant concentration of caseins, calcium (Ca), and phosphate (P(i)) in media with different citrate (Cit) concentrations was studied. The incorporation of the different mineral and protein components to the ACM was conditioned by the Cit concentration. In our working condition, the ACM size remained almost constant for Cit concentration ranging from 7 to 10 mM. This behavior could be indicating that the action of Cit essentially consists of a regulation of the Ca activity. The molar ratio at which Ca and P(i) were incorporated to the ACM varied for different Cit concentrations. At decreasing pH, the Ca/P(i) molar ratios for the remanent ions in the ACM were dependent on the Cit concentration. These observations could be related to a certain kind of competition between Cit, micellar calcium phosphate (MCP), and other groups able to bind Ca in the ACM.


Assuntos
Caseínas/química , Citratos/química , Micelas , Minerais/análise , Ânions
15.
Cell Death Dis ; 5: e1185, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24743740

RESUMO

Met, the tyrosine kinase receptor for hepatocyte growth factor (HGF), mainly activates prosurvival pathways, including protection from apoptosis. In this work, we investigated the cardioprotective mechanisms of Met activation by agonist monoclonal antibodies (mAbs). Cobalt chloride (CoCl2), a chemical mimetic of hypoxia, was used to induce cardiac damage in H9c2 cardiomyoblasts, which resulted in reduction of cell viability by (i) caspase-dependent apoptosis and (ii) - surprisingly - autophagy. Blocking either apoptosis with the caspase inhibitor benzyloxycarbonyl-VAD-fluoromethylketone or autophagosome formation with 3-methyladenine prevented loss of cell viability, which suggests that both processes contribute to cardiomyoblast injury. Concomitant treatment with Met-activating antibodies or HGF prevented apoptosis and autophagy. Pro-autophagic Redd1, Bnip3 and phospho-AMPK proteins, which are known to promote autophagy through inactivation of the mTOR pathway, were induced by CoCl2. Mechanistically, Met agonist antibodies or HGF prevented the inhibition of mTOR and reduced the flux of autophagosome formation. Accordingly, their anti-autophagic function was completely blunted by Temsirolimus, a specific mTOR inhibitor. Targeted Met activation was successful also in the setting of low oxygen conditions, in which Met agonist antibodies or HGF demonstrated anti-apoptotic and anti-autophagic effects. Activation of the Met pathway is thus a promising novel therapeutic tool for ischaemic injury.


Assuntos
Anticorpos Monoclonais/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Cardiotônicos/farmacologia , Citoproteção/efeitos dos fármacos , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-met/agonistas , Animais , Linhagem Celular , Cobalto , Fator de Crescimento de Hepatócito/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
16.
Science ; 332(6034): 1167-70, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21636766

RESUMO

A quantum fluid passing an obstacle behaves differently from a classical one. When the flow is slow enough, the quantum gas enters a superfluid regime, and neither whirlpools nor waves form around the obstacle. For higher flow velocities, it has been predicted that the perturbation induced by the defect gives rise to the turbulent emission of quantized vortices and to the nucleation of solitons. Using an interacting Bose gas of exciton-polaritons in a semiconductor microcavity, we report the transition from superfluidity to the hydrodynamic formation of oblique dark solitons and vortex streets in the wake of a potential barrier. The direct observation of these topological excitations provides key information on the mechanisms of superflow and shows the potential of polariton condensates for quantum turbulence studies.

17.
J Comp Pathol ; 142(1): 74-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19631945

RESUMO

Proliferative and necrotizing pneumonia (PNP) is a form of interstitial pneumonia that occurs in weaning and post-weaning pigs. PNP is characterized by hypertrophy and hyperplasia of type II pneumocytes and coagulative necrosis and granular debris within alveolar spaces. Canadian and European studies suggest that the porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) are the main causes of the disease, but Aujezsky's disease virus (ADV) and swine influenza virus (SIV) have also been considered as potential aetiological agents. An immunohistochemical study was carried out on the lungs of 28 Italian pigs with PNP in order to evaluate the role of PRRSV, PCV2 and ADV in PNP lesions. PRRSV infection was identified in the lungs of 11 pigs, PCV2 in the lungs of four pigs and coinfection with both viruses in the lungs of eight pigs. Neither virus was detected in the lungs of the remaining five pigs. ADV antigen was not detected in any sample. The principle aetiological agent of PNP in Italy therefore appears to be PRRSV. Coinfection with PRRSV and PCV2 is characterized by more severe microscopical changes in affected lungs.


Assuntos
Doenças Pulmonares Intersticiais/microbiologia , Doenças Pulmonares Intersticiais/veterinária , Doenças dos Suínos/microbiologia , Animais , Antígenos Virais/biossíntese , Circovirus/isolamento & purificação , Herpesvirus Suídeo 1/isolamento & purificação , Imuno-Histoquímica , Itália , Doenças Pulmonares Intersticiais/patologia , Orthomyxoviridae/isolamento & purificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Suínos , Doenças dos Suínos/patologia
19.
J Vet Med A Physiol Pathol Clin Med ; 54(2): 70-5, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17305969

RESUMO

The aims of this study were the evaluation of a quantitative method for the assessment of pneumonia lesions applied to heavy-weight slaughtered pigs, the identification of risk factors connected with the increase in the prevalence and severity of the lesions and the evaluation of a possible correlation between the presence of pneumonia lesions and the decrease in the carcass quality. The lungs of 10 041 pigs (109 slaughtered batches) coming from 91 farms located in Northern Italy were examined. Lung lesions were scored using the method developed by Madec and Kobisch (Journ. Rech. Porc. Fr., 14, 1982, 405). Before the scoring, anamnestic information regarding the farm of origin of each batch were collected. For 41 batches (3603 pigs), information about carcass quality were also collected. Pneumonia lesions were found in 59.6% of the lungs (range 3-91%), and the average batch score was 2.11 (range 0.03-7.15). We identified as farm risk factors those related to an increase in the severity of the lung lesions, the presence of breeders within the herd, the starting of a growing cycle during the winter season and the lack of vaccination programmes to Mycoplasma hyopneumoniae. Moreover, we also found a statistically significant association between the increase in the mean lung score of the batch and the decrease of the carcass quality.


Assuntos
Matadouros , Pulmão/patologia , Pneumonia por Mycoplasma/veterinária , Doenças dos Suínos/patologia , Animais , Itália , Pneumonia por Mycoplasma/patologia , Índice de Gravidade de Doença , Suínos
20.
Pharmacol Res ; 34(3-4): 121-4, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9051702

RESUMO

Naftopidil, an alpha 1-adrenergic antagonist, was orally tested in comparison with prazosin, in a rat cystomanometric model to evaluate the effect on the bladder volume capacity (BVC), the micturition pressure (MP) and the mean arterial blood pressure (MAP), contemporaneously recorded to evaluate the selectivity of action. Naftopidil induced a clearcut increase of BVC and a decrease of MP without lowering MAP at 6.25 mg kg-1 p.o.. Prazosin was inactive on BVC, decreased MP and induced a significant decrease of MAP at 1.56 mg kg-1 p.o. Naftopidil could offer an advantage when compared with prazosin.


Assuntos
Antagonistas Adrenérgicos alfa/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Naftalenos/farmacologia , Piperazinas/farmacologia , Prazosina/farmacologia , Urodinâmica/efeitos dos fármacos , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Bexiga Urinária/efeitos dos fármacos
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