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1.
Artigo em Inglês | MEDLINE | ID: mdl-38521444

RESUMO

Hypometabolism is a common strategy employed by resilient species to withstand environmental stressors that would be life-threatening for other organisms. Under conditions such as hypoxia/anoxia, temperature and salinity stress, or seasonal changes (e.g. hibernation, estivation), stress-tolerant species down-regulate pathways to decrease energy expenditures until the return of less challenging conditions. However, it is with the return of these more favorable conditions and the reactivation of basal metabolic rates that a strong increase of reactive oxygen and nitrogen species (RONS) occurs, leading to oxidative stress. Over the last few decades, cases of species capable of enhancing antioxidant defenses during hypometabolic states have been reported across taxa and in response to a variety of stressors. Interpreted as an adaptive mechanism to counteract RONS formation during tissue hypometabolism and reactivation, this strategy was coined "Preparation for Oxidative Stress" (POS). Laboratory experiments have confirmed that over 100 species, spanning 9 animal phyla, apply this strategy to endure harsh environments. However, the challenge remains to confirm its occurrence in the natural environment and its wide applicability as a key survival element, through controlled experimentation in field and in natural conditions. Under such conditions, numerous confounding factors may complicate data interpretation, but this remains the only approach to provide an integrative look at the evolutionary aspects of ecophysiological adaptations. In this review, we provide an overview of representative cases where the POS strategy has been demonstrated among diverse species in natural environmental conditions, discussing the strengths and weaknesses of these results and conclusions.


Assuntos
Antioxidantes , Estresse Oxidativo , Animais , Estresse Oxidativo/fisiologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Meio Ambiente , Oxigênio , Hipóxia/metabolismo , Espécies Reativas de Nitrogênio
2.
iScience ; 27(1): 108727, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38235324

RESUMO

The quiescent state is the prevalent mode of cellular life in most cells. Saccharomyces cerevisiae is a useful model for studying the molecular basis of the cell cycle, quiescence, and aging. Previous studies indicate that heterogeneous ribosomes show a specialized translation function to adjust the cellular proteome upon a specific stimulus. Using nano LC-MS/MS, we identified 69 of the 79 ribosomal proteins (RPs) that constitute the eukaryotic 80S ribosome during quiescence. Our study shows that the riboproteome is composed of 444 accessory proteins comprising cellular functions such as translation, protein folding, amino acid and glucose metabolism, cellular responses to oxidative stress, and protein degradation. Furthermore, the stoichiometry of both RPs and accessory proteins on ribosome particles is different depending on growth conditions and among monosome and polysome fractions. Deficiency of different RPs resulted in defects of translational capacity, suggesting that ribosome composition can result in changes in translational activity during quiescence.

3.
J Clin Med ; 12(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685572

RESUMO

In 2020, Spain ranked fourth among European countries with the highest excess mortality due to COVID-19 disease. This study evaluates the impact of the COVID-19 pandemic on non-COVID patients in a tertiary hospital during the second pandemic wave in Spain (22 June 2020-6 December 2020). Data from Virgen del Rocío University Hospital in Seville during that timeframe were compared with the data from the same period in the preceding two years (2018-2019). Between-group comparisons were performed using the Chi-squared test, Student's t-test, or Mann-Whitney U tests, as appropriate. A total of 63,137 non-COVID patients were included in this study. During the second pandemic wave, a 19% decrease was observed in the annual number of non-COVID admissions overall (18,260 vs. 22,439, p < 0.001), but a 10% increase in the proportion of emergency admissions (60.6% vs. 54.93%, p < 0.001), a higher severity level of patients (1.79 vs. 1.72, p < 0.001), a longer in-hospital stay (7.02 vs. 6.74 days, p < 0.001), a 26% increase in non-COVID mortality (4.9% vs. 3.9%, p < 0.001), and a 50% increase in global mortality (5.9 vs. 3.9, p < 0.001) were also observed. In terms of both medical and surgical diagnoses, a significant reduction in the number of admissions and an increase in in-hospital mortality were observed. These results demonstrate the significant impact of the pandemic on hospital care, similar to what was previously observed during the initial wave in the same hospital. Our findings emphasize the need to include non-COVID patients when assessing the broad impact of the pandemic on healthcare, beyond its direct effects on COVID-19 patients.

4.
Actual. osteol ; 19(2): 128-143, sept. 2023. ilus, tab
Artigo em Espanhol | LILACS, UNISALUD, BINACIS | ID: biblio-1523882

RESUMO

El presente trabajo muestra la obtención de un material a partir de un polímero sintético (TerP) y otro natural, mediante entrecruzamiento físico y su caracterización fisicoquímica y biológica, con el fin de emplearlos para regeneración de tejido óseo. Las membranas fueron obtenidas por la técnica de evaporación del solvente y caracterizadas por espectroscopia FTIR, ensayos de hinchamiento, medidas de ángulo de contacto y microscopia electrónica de barrido (SEM). Se encontró que la compatibilidad entre los polímeros que la constituyen es estable a pH fisiológico y que, al incorporar mayor cantidad del TerP a la matriz, esta se vuelve más hidrofóbica y porosa. Además, teniendo en cuenta la aplicación prevista para dichos materiales, se realizaron estudios de biocompatibilidad y citotoxicidad con células progenitoras de médula ósea (CPMO) y células RAW264.7, respectivamente. Se evaluó la proliferación celular, la producción y liberación de óxido nítrico (NO) al medio de cultivo durante 24 y 48 horas y la expresión de citoquinas proinflamatorias IL-1ß y TNF-α de las células crecidas sobre los biomateriales variando la cantidad del polímero sintético. Se encontró mayor proliferación celular y menor producción de NO sobre las matrices que contienen menos proporción del TerP, además de poseer una mejor biocompatibilidad. Los resultados de este estudio muestran que el terpolímero obtenido y su combinación con un polímero natural es una estrategia muy interesante para obtener un biomaterial con posibles aplicaciones en medicina regenerativa y que podría extenderse a otros sistemas estructuralmente relacionados. (AU)


In the present work, the preparation of a biomaterial from a synthetic terpolymer (TerP) and a natural polymer, physically crosslinked, is shown. In order to evaluate the new material for bone tissue regeneration, physicochemical and biological characterizations were performed. The membranes were obtained by solvent casting and characterized using FTIR spectroscopy, swelling tests, contact angle measurements, and scanning electron microscopy (SEM). It was found that the compatibility between the polymers is stable at physiological pH and the incorporation of a higher amount of TerP into the matrix increases hydrophobicity and porosity.Furthermore, considering the intended application of these materials, studies of biocompatibility and cytotoxicity were conducted with Bone Marrow Progenitor Cells (BMPCs) and RAW264.7 cells, respectively. Cell proliferation, NO production and release into the culture medium for 24 and 48 hours, and proinflammatory cytokine expression of IL-1ß and TNF-α from cells grown on the biomaterials while varying the amount of the synthetic polymer were evaluated. Greater cell proliferation and lower NO production were found on matrices containing a lower proportion of TerP, in addition to better biocompatibility. The results of this study demonstrate that the obtained terpolymer and its combination with a natural polymer is a highly interesting strategy for biomaterial preparation with potential applications in regenerative medicine. This approach could be extended to other structurally related systems. (AU)


Assuntos
Animais , Ratos , Osteogênese , Polímeros/química , Materiais Biocompatíveis/síntese química , Osso e Ossos/química , Regeneração Óssea , Quitosana/química , Polímeros/toxicidade , Materiais Biocompatíveis/toxicidade , Teste de Materiais , Diferenciação Celular , Cromatografia em Gel , Espectroscopia de Infravermelho com Transformada de Fourier , Técnicas de Cultura de Células , Ressonância Magnética Nuclear Biomolecular , Quitosana/toxicidade
5.
Sci Rep ; 13(1): 1634, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717651

RESUMO

We assessed the impact of the first wave of COVID-19 pandemic on non-COVID hospital admissions, non-COVID mortality, factors associated with non-COVID mortality, and changes in the profile of non-COVID patients admitted to hospital. We used the Spanish Minimum Basic Data Set with diagnosis grouped according to the Diagnostic Related Groups. A total of 10,594 patients (3% COVID-19; 97% non-COVID) hospitalised during the first wave in 2020 (27-February/07-June) were compared with those hospitalised within the same dates of 2017-2019 (average annual admissions: 14,037). We found a decrease in non-COVID medical (22%) and surgical (33%) hospitalisations and a 25.7% increase in hospital mortality among non-COVID patients during the first pandemic wave compared to pre-pandemic years. During the officially declared sub-period of excess mortality in the area (17-March/20-April, in-hospital non-COVID mortality was even higher (58.7% higher than the pre-pandemic years). Non-COVID patients hospitalised during the first pandemic wave (compared to pre-pandemic years) were older, more frequently men, with longer hospital stay and increased disease severity. Hospitalisation during the first pandemic wave in 2020, compared to hospitalisation during the pre-pandemic years, was an independent risk factor for non-COVID mortality (HR 1.30, 95% CI 1.07-1.57, p = 0.008), reflecting the negative impact of the pandemic on hospitalised patients.


Assuntos
COVID-19 , Masculino , Humanos , COVID-19/epidemiologia , Pandemias , Pacientes Internados , Espanha/epidemiologia , Hospitalização , Mortalidade Hospitalar , Estudos Retrospectivos
6.
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
7.
Sci Rep ; 12(1): 9961, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705598

RESUMO

Alteration of muscle activation sequence is a key mechanism in heart failure with reduced ejection fraction. Successful cardiac resynchronization therapy (CRT), which has become standard therapy in these patients, is limited by the lack of precise dyssynchrony quantification. We implemented a computational pipeline that allows assessment of ventricular dyssynchrony by vectorcardiogram reconstruction from the patient's electrocardiogram. We defined a ventricular dyssynchrony index as the distance between the voltage and speed time integrals of an individual observation and the linear fit of these variables obtained from a healthy population. The pipeline was tested in a 1914-patient population. The dyssynchrony index showed minimum values in heathy controls and maximum values in patients with left bundle branch block (LBBB) or with a pacemaker (PM). We established a critical dyssynchrony index value that discriminates electrical dyssynchronous patterns (LBBB and PM) from ventricular synchrony. In 10 patients with PM or CRT devices, dyssynchrony indexes above the critical value were associated with high time to peak strain standard deviation, an echocardiographic measure of mechanical dyssynchrony. Our index proves to be a promising tool to evaluate ventricular activation dyssynchrony, potentially enhancing the selection of candidates for CRT, device configuration during implantation, and post-implant optimization.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Arritmias Cardíacas , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/terapia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/terapia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Vetorcardiografia
8.
J Med Virol ; 94(3): 1175-1185, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34761824

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has particularly affected countries with weakened health services in Latin America, where proper patient management could be a critical step to address the epidemic. In this study, we aimed to characterize and identify which epidemiological, clinical, and paraclinical risk factors defined COVID-19 infection from the first confirmed cases through the first epidemic wave in Venezuela. A retrospective analysis of consecutive suspected cases of COVID-19 admitted to a sentinel hospital was carried out, including 576 patient cases subsequently confirmed for severe acute respiratory syndrome coronavirus 2 infection. Of these, 162 (28.1%) patients met the definition criteria for severe/critical disease, and 414 (71.2%) were classified as mild/moderate disease. The mean age was 47 (SD 16) years, the majority of which were men (59.5%), and the most frequent comorbidity was arterial hypertension (23.3%). The most common symptoms included fever (88.7%), headache (65.6%), and dry cough (63.9%). Severe/critical disease affected mostly older males with low schooling (p < 0.001). Similarly, higher levels of glycemia, urea, aminotransferases, total bilirubin, lactate dehydrogenase, and erythrocyte sedimentation rate were observed in severe/critical disease patients compared to those with mild/moderate disease. Overall mortality was 7.6% (44/576), with 41.7% (28/68) dying in hospital. We identified risk factors related to COVID-19 infection, which could help healthcare providers take appropriate measures and prevent severe clinical outcomes. Our results suggest that the mortality registered by this disease in Venezuela during the first epidemic wave was underestimated. An increase in fatalities is expected to occur in the coming months unless measures that are more effective are implemented to mitigate the epidemic while the vaccination process is ongoing.


Assuntos
COVID-19 , COVID-19/diagnóstico , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Venezuela/epidemiologia
9.
Front Physiol ; 12: 769833, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34955885

RESUMO

The upregulation of endogenous antioxidants (i.e., preparation for oxidative stress, POS) is part of the biochemical responses underlying the adaptation of animals to adverse environments. Despite the phylogenetic diversity of animals in which POS has been described, most studies focus on animals under controlled laboratory conditions. To address this limitation, we have recently assessed the redox metabolism in the skeletal muscle of Proceratophrys cristiceps estivating under natural settings in the Caatinga. Here, we analyzed biochemical biomarkers in the muscle of another Caatinga species, Pleurodema diplolister, during the rainy (active) and dry (estivating frogs) seasons. We aimed to determine whether P. diplolister enhances its antioxidants during estivation under field conditions and to identify any effect of species on the biochemical responses of P. diplolister and P. cristiceps associated with estivation. To do so, we measured the activities of representative enzymes of intermediary metabolism and antioxidant systems, as well as glutathione and protein carbonyl levels, in the skeletal muscle of P. diplolister. Our findings revealed the suppression of oxidative metabolism and activation of antioxidant enzymes in estivating P. diplolister compared with active specimens. No changes in oxidative damage to proteins were observed and estivating P. diplolister had lower levels of disulfide glutathione (GSSG) and disulfide-to-total glutathione ratio (GSSG/tGSH) than those observed in active individuals. When data for P. diplolister and P. cristiceps were assembled and analyzed, significant effects of species were detected on the activities of metabolic enzymes (citrate synthase, isocitric dehydrogenase, malic enzyme, and creatine kinase) and antioxidant enzymes (catalase, glutathione peroxidase and glutathione transferase), as well as on GSSG/tGSH ratio. Such effects might underlie the physiological and behavioral differences between these two species that share the same microhabitat and survival strategy (i.e., to estivate) during the dry season. Despite some peculiarities, which reflect the physiological diversity of the mechanisms associated with estivation in the Brazilian Caatinga, both P. diplolister and P. cristiceps seem to balance the suppression of oxidative pathways, the maintenance of the capacity of oxygen-independent pathways, and the activation of endogenous antioxidants to preserve muscle function and be ready to resume activity whenever the unpredictable rainy period arrives.

10.
Int J Numer Method Biomed Eng ; 37(11): e3261, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-31617333

RESUMO

Aortic cross-clamping is a common strategy during vascular surgery, however, its instantaneous impact on hemodynamics is unknown. We, therefore, developed two numerical models to estimate the immediate impact of aortic clamping on the vascular properties. To assess the validity of the models, we recorded continuous invasive pressure signals during abdominal aneurysm repair surgery, immediately before and after clamping. The first model is a zero-dimensional (0D) three-element Windkessel model, which we coupled to a gradient-based parameter estimation algorithm to identify patient-specific parameters such as vascular resistance and compliance. We found a 10% increase in the total resistance and a 20% decrease in the total compliance after clamping. The second model is a nine-artery network corresponding to an average human body in which we solved the one-dimensional (1D) blood flow equations. With a similar parameter estimation method and using the results from the 0D model, we identified the resistance boundary conditions of the 1D network. Determining the patient-specific total resistance and the distribution of peripheral resistances through the parameter estimation process was sufficient for the 1D model to accurately reproduce the impact of clamping on the pressure waveform. Both models gave an accurate description of the pressure wave and had a high correlation (R2 > .95) with experimental blood pressure data.


Assuntos
Aorta , Hemodinâmica , Pressão Sanguínea , Constrição , Humanos , Resistência Vascular
11.
Sci Total Environ ; 723: 137957, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32220732

RESUMO

Preparation for oxidative stress (POS), i.e., the buildup of endogenous antioxidants during metabolic depression or low oxygen stress conditions, has been observed in at least 8 animal phyla under controlled conditions in laboratory. Despite the expected implications on the endurance to extreme environments and ecosystem occupation, the extent to which POS occurs in animals under natural conditions remains unexplored. Therefore, we took advantage of the natural history of the Brazilian Caatinga's frog Proceratophrys cristiceps to investigate the modulation of endogenous antioxidants and redox balance in their skeletal muscle and to verify if POS occurs under natural conditions. Expectedly, estivating frogs had low levels of the oxidative metabolism enzymes. Citrate synthase and isocitrate dehydrogenase activities were 36% and 25% lower than those in active frogs respectively. We found an overall upregulation of antioxidants in estivating P. cristiceps. Reduced glutathione concentration was 61% higher in estivating frogs than that in active animals. During estivation the activities of the hydroperoxide detoxification enzymes catalase, glutathione peroxidase, and glutathione H2O2-peroxidase were 48%, 57%, and 78% greater than those during the rainy season. Moreover, estivating frogs had a 47% lower ratio of disulfide to total glutathione levels than active frogs. Our findings confirm the occurrence of 'preparation for oxidative stress' in naturally estivating frogs and paves the way for further research on the redox biology of animals under natural settings. Such approach might reveal biochemical strategies under ecologically relevant scenarios.


Assuntos
Anuros , Ecossistema , Animais , Antioxidantes , Brasil , Glutationa , Peróxido de Hidrogênio , Estresse Oxidativo
12.
Perioper Med (Lond) ; 9: 1, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31921411

RESUMO

INTRODUCTION: Closed loop total intravenous anesthesia is a technique in which the patient's hemodynamic and anesthetic depth variables are monitored, and based on this information, a computer controls the infusion rate of drugs to keep them within pre-established clinical parameters. OBJECTIVE: To describe the technical and clinical performance of a closed loop system for total intravenous anesthesia with propofol and remifentanil, using the SEDLineTM monitor. DESIGN: Multicentric prospective cohort study. SETTING: Surgery room. PATIENTS: ASA I-II undergoing elective surgery. MEASUREMENTS: The authors designed a closed loop system that implements a control algorithm based on anesthetic depth monitoring and the Patient State Index (PSITM) of the SEDLine monitor for propofol, and on hemodynamic variables for remifentanil. The measurement of clinical performance was made based on the percentage of PSITM maintenance time in the range 20-50. Precision analysis was evaluated by measuring median performance error (MDPE) can be defined as the median difference between actual and desired values, which refers to the degree of precision in which the controller is able to maintain the control variable within the objective set by the anesthesiologist; it represents the direction (over-prediction or under-prediction) of performance error (PE) rather than size of errors, which is represented by MDAPE, median absolute percentage error, Wobble index, which is used for measuring the intrasubject variability in performance error. RESULTS: Data were obtained from 93 patients in three healthcare centers. The percentage of PSITM maintenance time in the 20-50 range was 92% (80.7-97.0). MDPE was 10.7 (- 11.0-18.0), MDAPE 21.0 (14.2-26.8) and wobble 10.7 (7.0-16.9). No adverse surgical or anesthetic events were found. CONCLUSIONS: The closed loop total intravenous anesthesia system with SEDLine developed by the authors was used without major complication and appear to be feasible its use in clinical performance.

13.
J Biomed Mater Res B Appl Biomater ; 108(4): 1428-1438, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31520507

RESUMO

The objective of this study was to test a regenerative medicine strategy for the regeneration of articular cartilage. This approach combines microfracture of the subchondral bone with the implant at the site of the cartilage defect of a supporting biomaterial in the form of microspheres aimed at creating an adequate biomechanical environment for the differentiation of the mesenchymal stem cells that migrate from the bone marrow. The possible inflammatory response to these biomaterials was previously studied by means of the culture of RAW264.7 macrophages. The microspheres were implanted in a 3 mm-diameter defect in the trochlea of the femoral condyle of New Zealand rabbits, covering them with a poly(l-lactic acid) (PLLA) membrane manufactured by electrospinning. Experimental groups included a group where exclusively PLLA microspheres were implanted, another group where a mixture of 50/50 microspheres of PLLA (hydrophobic and rigid) and others of chitosan (a hydrogel) were used, and a third group used as a control where no material was used and only the membrane was covering the defect. The histological characteristics of the regenerated tissue have been evaluated 3 months after the operation. We found that during the regeneration process the microspheres, and the membrane covering them, are displaced by the neoformed tissue in the regeneration space toward the subchondral bone region, leaving room for the formation of a tissue with the characteristics of hyaline cartilage.


Assuntos
Materiais Biocompatíveis , Cartilagem Hialina/metabolismo , Articulação do Joelho/metabolismo , Microesferas , Poliésteres , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Masculino , Camundongos , Poliésteres/química , Poliésteres/farmacologia , Células RAW 264.7 , Coelhos
14.
Artigo em Inglês | MEDLINE | ID: mdl-30978470

RESUMO

Freezing, dehydration, salinity variations, hypoxia or anoxia are some of the environmental constraints that many organisms must frequently endure. Organisms adapted to these stressors often reduce their metabolic rates to maximize their chances of survival. However, upon recovery of environmental conditions and basal metabolic rates, cells are affected by an oxidative burst that, if uncontrolled, leads to (oxidative) cell damage and eventually death. Thus, a number of adapted organisms are able to increase their antioxidant defenses during an environmental/functional hypoxic transgression; a strategy that was interpreted in the 1990s as a "preparation for oxidative stress" (POS). Since that time, POS mechanisms have been identified in at least 83 animal species representing different phyla including Cnidaria, Nematoda, Annelida, Tardigrada, Echinodermata, Arthropoda, Mollusca and Chordata. Coinciding with the 20th anniversary of the postulation of the POS hypothesis, we compiled this review where we analyze a selection of examples of species showing POS-mechanisms and review the most recent advances in understanding the underlying molecular mechanisms behind those strategies that allow animals to survive in harsh environments.


Assuntos
Adaptação Fisiológica/genética , Evolução Molecular , Hipóxia , Estresse Oxidativo/fisiologia , Animais , Anelídeos/fisiologia , Desidratação/metabolismo , Congelamento/efeitos adversos , Moluscos/fisiologia , Estresse Oxidativo/genética , Salinidade
15.
Lancet Neurol ; 18(1): 46-55, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30413385

RESUMO

BACKGROUND: CT perfusion (CTP) and diffusion or perfusion MRI might assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of irreversibly injured ischaemic core and potentially salvageable penumbra volumes were associated with functional outcome and whether they interacted with the treatment effect of endovascular thrombectomy on functional outcome. METHODS: In this systematic review and meta-analysis, the HERMES collaboration pooled patient-level data from all randomised controlled trials that compared endovascular thrombectomy (predominantly using stent retrievers) with standard medical therapy in patients with anterior circulation ischaemic stroke, published in PubMed from Jan 1, 2010, to May 31, 2017. The primary endpoint was functional outcome, assessed by the modified Rankin Scale (mRS) at 90 days after stroke. Ischaemic core was estimated, before treatment with either endovascular thrombectomy or standard medical therapy, by CTP as relative cerebral blood flow less than 30% of normal brain blood flow or by MRI as an apparent diffusion coefficient less than 620 µm2/s. Critically hypoperfused tissue was estimated as the volume of tissue with a CTP time to maximum longer than 6 s. Mismatch volume (ie, the estimated penumbral volume) was calculated as critically hypoperfused tissue volume minus ischaemic core volume. The association of ischaemic core and penumbral volumes with 90-day mRS score was analysed with multivariable logistic regression (functional independence, defined as mRS score 0-2) and ordinal logistic regression (functional improvement by at least one mRS category) in all patients and in a subset of those with more than 50% endovascular reperfusion, adjusted for baseline prognostic variables. The meta-analysis was prospectively designed by the HERMES executive committee, but not registered. FINDINGS: We identified seven studies with 1764 patients, all of which were included in the meta-analysis. CTP was available and assessable for 591 (34%) patients and diffusion MRI for 309 (18%) patients. Functional independence was worse in patients who had CTP versus those who had diffusion MRI, after adjustment for ischaemic core volume (odds ratio [OR] 0·47 [95% CI 0·30-0·72], p=0·0007), so the imaging modalities were not pooled. Increasing ischaemic core volume was associated with reduced likelihood of functional independence (CTP OR 0·77 [0·69-0·86] per 10 mL, pinteraction=0·29; diffusion MRI OR 0·87 [0·81-0·94] per 10 mL, pinteraction=0·94). Mismatch volume, examined only in the CTP group because of the small numbers of patients who had perfusion MRI, was not associated with either functional independence or functional improvement. In patients with CTP with more than 50% endovascular reperfusion (n=186), age, ischaemic core volume, and imaging-to-reperfusion time were independently associated with functional improvement. Risk of bias between studies was generally low. INTERPRETATION: Estimated ischaemic core volume was independently associated with functional independence and functional improvement but did not modify the treatment benefit of endovascular thrombectomy over standard medical therapy for improved functional outcome. Combining ischaemic core volume with age and expected imaging-to-reperfusion time will improve assessment of prognosis and might inform endovascular thrombectomy treatment decisions. FUNDING: Medtronic.


Assuntos
Isquemia Encefálica/terapia , Encéfalo/diagnóstico por imagem , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/terapia , Trombectomia/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuroimagem , Imagem de Perfusão , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
16.
Pain Physician ; 20(4): E499-E505, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28535558

RESUMO

BACKGROUND: Low back pain (LBP) is the most common musculoskeletal disorder affecting the general population and it is believed to be associated with depression. OBJECTIVE: The study aim was to describe and compare the impact in a sample of people with subacute LBP (SLBP) and patients without LBP with normalized reference values in the light of the scores obtained with regard using the Beck Depression Inventory (BDI). STUDY DESIGN: This was a case-control study. SETTINGS: Physiotherapist area at a care center. METHODS: A sample of 164 participants of a mean age of 41.45 ± 0.97 came to a physical therapy clinic where self-reported data were registered, informants' professional activity was determined, and the scores obtained were compared in the BDI. RESULTS: Total BDI scores at SLBP and their controls were 21.52 ± 6.93 (11 - 43) and 17.30 ± 5.09 (11 - 30), respectively (P < 0.001). The SLBP patient has 2.12 times more likely to have moderate depression (OR 2.12 (1.07 - 4.18) and 18.82 times more likely to have serious depression (OR 18.82 (1.06 - 331.81) compared to their controls (P < 0.05). LIMITATIONS: The study was not a randomized controlled trial. Although primary outcome data were self-reported, the assessor was not blinded. CONCLUSIONS: People with SLBP also have a significant increase in depression based on BDI scores, regardless of gender.


Assuntos
Depressão/complicações , Dor Lombar/complicações , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato , Adulto Jovem
17.
Oncotarget ; 6(30): 30343-56, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26327509

RESUMO

Reliable biological markers that predict breast cancer (BC) outcomes after multidisciplinary therapy have not been fully elucidated. We investigated the association between casein kinase 1 epsilon (CK1ε) and the risk of recurrence in patients with BC. Using 168 available tumor samples from patients with BC treated with surgery +/- chemo(radio)therapy, we scored the CK1ε expression as high (≥ 1.5) or low (<1.5) using an immunohistochemical method. Kaplan-Meier analysis was performed to assess the risk of relapse, and Cox proportional hazards analyses were utilized to evaluate the effect of CK1ε expression on this risk. The median age at diagnosis was 60 years (range 35-96). A total of 58% of the patients underwent breast conservation surgery, while 42% underwent mastectomy. Adjuvant chemotherapy and radiation therapy were administered in 101 (60%) and 137 cases (82%), respectively. Relapse was observed in 24 patients (14%). Multivariate analysis found high expression of CK1ε to be associated with a statistically significant higher disease-free survival (DFS) in BC patients with wild-type p53 (Hazard ratio [HR] = 0.33; 95% CI, 0.12-0.91; P = 0.018) or poor histological differentiation ([HR] = 0.34; 95% CI, 0.12-0.94; P = 0.039) or in those without adjuvant chemotherapy ([HR] = 0.11; 95% CI, 0.01-0.97; P = 0.006). Our data indicate that CK1ε expression is associated with DFS in BC patients with wild-type p53 or poor histological differentiation or in those without adjuvant chemotherapy and thus may serve as a predictor of recurrence in these subsets of patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/enzimologia , Caseína Quinase 1 épsilon/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Caseína Quinase 1 épsilon/genética , Diferenciação Celular , Linhagem Celular Tumoral , Quimioterapia Adjuvante , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Mastectomia , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Transfecção , Resultado do Tratamento , Proteína Supressora de Tumor p53/genética , Regulação para Cima
18.
Front Plant Sci ; 6: 464, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26167167

RESUMO

Applying proteomics, we tested the physiological responses of the euryhaline seagrass Cymodocea nodosa to deliberate manipulation of salinity in a mesocosm system. Plants were subjected to a chronic hypersaline condition (43 psu) to compare protein expression and plant photochemistry responses after 15 and 30 days of exposure with those of plants cultured under normal/ambient saline conditions (37 psu). Results showed a general decline in the expression level of leaf proteins in hypersaline stressed plants, with more intense reductions after long-lasting exposure. Specifically, the carbon-fixing enzyme RuBisCo displayed a lower accumulation level in stressed plants relative to controls. In contrast, the key enzymes involved in the regulation of glycolysis, cytosolic glyceraldehyde-3-phosphate dehydrogenase, enolase 2 and triose-phosphate isomerase, showed significantly higher accumulation levels. These responses suggested a shift in carbon metabolism in stressed plants. Hypersaline stress also induced a significant alteration of the photosynthetic physiology of C. nodosa by means of a down-regulation in structural proteins and enzymes of both PSII and PSI. However we found an over-expression of the cytochrome b559 alpha subunit of the PSII initial complex, which is a receptor for the PSII core proteins involved in biogenesis or repair processes and therefore potentially involved in the absence of effects at the photochemical level of stressed plants. As expected hypersalinity also affects vacuolar metabolism by increasing the leaf cell turgor pressure and enhancing the up-take of Na(+) by over-accumulating the tonoplast specific intrinsic protein pyrophosphate-energized inorganic pyrophosphatase (H(+)-PPase) coupled to the Na(+)/H(+)-antiporter. The modulation of carbon metabolism and the enhancement of vacuole capacity in Na(+) sequestration and osmolarity changes are discussed in relation to salt tolerance of C. nodosa.

19.
J Acoust Soc Am ; 136(3): 1077, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25190383

RESUMO

The acoustic attenuation spectrum of lipid-coated microbubble suspensions was measured in order to characterize the linear acoustic behavior of ultrasound contrast agents. For that purpose, microbubbles samples were generated with a very narrow size distribution by using microfluidics techniques. A performance as good as optical characterization techniques of single microbubbles was achieved using this method. Compared to polydispersions (i.e., contrast agents used clinically), monodisperse contrast agents have a narrower attenuation spectrum, which presents a maximum peak at a frequency value corresponding to the average single bubble resonance frequency. The low polydispersity index of the samples made the estimation of the lipid viscoelastic properties more accurate since, as previously reported, the shell linear parameters may change with the equilibrium bubble radius. The results showed the great advantage of dealing with monodisperse populations rather than polydisperse populations for the acoustic characterization of ultrasound contrast agents.


Assuntos
Acústica , Meios de Contraste/química , Lipídeos/química , Microbolhas , Som , Elasticidade , Gases , Técnicas Analíticas Microfluídicas , Modelos Teóricos , Oscilometria , Tamanho da Partícula , Pressão , Tensão Superficial , Viscosidade
20.
Clin Med (Lond) ; 14(2): 157-64, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24715127

RESUMO

The objective of this study was to evaluate the 25-year outcome of patients with primary Sjögren's syndrome (pSS). One hundred and fifty-two patients diagnosed with pSS (American-European classification criteria) were retrospectively and descriptively analysed (1986-2011). Of all 152 patients, 55.9% were alive, 18.4% had died and 25.7% discontinued follow-up (mostly due to old age). Malignancy affected 28.3% and non-Hodgkin's lymphoma (NHL) affected 10.5%. The adjusted risk for development of NHL was an odds ratio (OR) of 10.5 (95% confidence interval [CI]: 3.05-36.42) in patients with vasculitis (p<0.001), and OR 3.4 (95% CI 1.05-11.2) in the presence of glandular complications (parotid swelling, lymphadenopathy) (p < 0.041). Seventy-five patients (49.3%) developed other autoimmune diseases (autoimmune thyroid disease [15.8%], pulmonary fibrosis [7.2%] and vasculitis [10.5%]). Although the course of pSS is relatively benign, over 25 years patients experience more clinical complications than previously described. In addition, vasculitis and glandular manifestations were significant predictors for NHL.


Assuntos
Doenças Autoimunes/epidemiologia , Linfoma não Hodgkin/epidemiologia , Síndrome de Sjogren/epidemiologia , Adulto , Idoso , Estudos de Coortes , Feminino , Seguimentos , Humanos , Doenças Linfáticas/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Razão de Chances , Prognóstico , Fibrose Pulmonar/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Síndrome de Sjogren/complicações , Síndrome de Sjogren/mortalidade , Tireoidite Autoimune/epidemiologia , Vasculite/epidemiologia
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