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1.
Annu Rev Cell Dev Biol ; 32: 555-576, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27501444

RESUMO

Metastasis is responsible for most cancer-associated deaths. Accumulating evidence based on 3D migration models has revealed a diversity of invasive migratory schemes reflecting the plasticity of tumor cells to switch between proteolytic and nonproteolytic modes of invasion. Yet, initial stages of localized regional tumor dissemination require proteolytic remodeling of the extracellular matrix to overcome tissue barriers. Recent data indicate that surface-exposed membrane type 1-matrix metalloproteinase (MT1-MMP), belonging to a group of membrane-anchored MMPs, plays a central role in pericellular matrix degradation during basement membrane and interstitial tissue transmigration programs. In addition, a large body of work indicates that MT1-MMP is targeted to specialized actin-rich cell protrusions termed invadopodia, which are responsible for matrix degradation. This review describes the multistep assembly of actin-based invadopodia in molecular details. Mechanisms underlying MT1-MMP traffic to invadopodia through endocytosis/recycling cycles, which are key to the invasive program of carcinoma cells, are discussed.


Assuntos
Metaloproteinase 14 da Matriz/metabolismo , Neoplasias/enzimologia , Neoplasias/patologia , Animais , Polaridade Celular , Humanos , Modelos Biológicos , Invasividade Neoplásica , Podossomos/metabolismo
2.
Nature ; 620(7975): 813-823, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37558877

RESUMO

Twenty-five years since foundational publications on valuing ecosystem services for human well-being1,2, addressing the global biodiversity crisis3 still implies confronting barriers to incorporating nature's diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever4. Notwithstanding agreements to incorporate nature's values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF)5 and the UN Sustainable Development Goals6, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature7. Arguably, a 'values crisis' underpins the intertwined crises of biodiversity loss and climate change8, pandemic emergence9 and socio-environmental injustices10. On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature's diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions7,11. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures.


Assuntos
Ecossistema , Justiça Ambiental , Política Ambiental , Objetivos , Desenvolvimento Sustentável , Humanos , Biodiversidade , Desenvolvimento Sustentável/economia , Política Ambiental/economia , Mudança Climática
3.
Am Heart J ; 264: 72-82, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37279839

RESUMO

BACKGROUND: Little data exist on the relationship between total stent length (TSL) and cardiovascular outcomes at very-long follow-up in patients with ST-elevation myocardial infarction (STEMI) in the 2nd generation drug-eluting stents (DES) era. AIM: To analyze the relationship between TSL and 10-year target-lesion failure (TLF) in STEMI patients treated with percutaneous coronary intervention enrolled in the EXAMINATION-EXTEND. METHODS: The EXAMINATION-EXTEND was an extended-follow-up study of the EXAMINATION trial, which randomized 1:1 STEMI patients to receive DES or bare metal stent (BMS). The primary endpoint was TLF, defined as a composite of target lesion revascularization (TLR), target vessel myocardial infarction (TVMI), or definite/probable stent thrombosis (ST). Relationship between stent length and TLF was evaluated in the whole study group in a multiple-adjusted Cox regression model with TSL as a quantitative variable. Subgroup analysis was also performed according to stent type, diameter, and overlap. RESULTS: A total of 1,489 patients with a median TSL of 23 mm (Q1-Q318-35 mm) were included. TSL was associated with TLF at 10 years (adjusted HR per 5 mm increase of 1.07; 95% CI, 1.01-1.14; P = .02). This effect was mainly driven by TLR and was consistent regardless of stent type, diameter, or overlap. There was no significant relationship between TSL and TV-MI or ST. CONCLUSIONS: In STEMI patients, there is a direct relationship between TSL implanted in the culprit vessel and the risk of TLF at 10 years, mainly driven by TLR. The use of DES did not modify this association.


Assuntos
Fármacos Cardiovasculares , Stents Farmacológicos , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Seguimentos , Resultado do Tratamento , Stents , Desenho de Prótese
4.
Biotechnol Bioeng ; 120(7): 1953-1960, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37232541

RESUMO

Viral vectors for gene therapy, such as recombinant adeno-associated viruses, are produced in human embryonic kidney (HEK) 293 cells. However, the presence of the SV40 T-antigen-encoding CDS SV40GP6 and SV40GP7 in the HEK293T genome raises safety issues when these cells are used in manufacturing for clinical purposes. We developed a new T-antigen-negative HEK cell line from ExcellGene's proprietary HEKExpress,® using the CRISPR-Cas9 strategy. We obtained a high number of clonally-derived cell populations and all of them were demonstrated T-antigen negative. Stability study and AAV production evaluation showed that the deletion of the T-antigen-encoding locus did not impact neither cell growth nor viability nor productivity. The resulting CMC-compliant cell line, named HEKzeroT,® is able to produce high AAV titers, from small to large scale.


Assuntos
Antígenos Virais de Tumores , Vetores Genéticos , Humanos , Células HEK293 , Antígenos Virais de Tumores/genética , Dependovirus/genética
5.
Catheter Cardiovasc Interv ; 102(4): 608-619, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37582340

RESUMO

BACKGROUND: Myocardial revascularization failure (MRF) and Secondary revascularization (SR) are contemporary interventional cardiology challenges. AIM: To investigate the characteristics, management, and prognosis of patients with myocardial revascularization failure (MRF) and need for secondary revascularization (SR) in contemporary practice. METHODS: The REVASEC study is a prospective registry (NCT03349385), which recruited patients with prior revascularization referred for coronary angiography at 19 centers. The primary endpoint is a patient-oriented composite (POCE) at 1 year, including death, myocardial infarction, or repeat revascularization. RESULTS: A total of 869 patients previously revascularized by percutaneous intervention (83%) or surgery (17%) were recruited. MRF was found in 83.7% (41.1% stent/graft failure, 32.1% progression of coronary disease, and 10.5% residual disease). SR was performed in 70.1%, preferably by percutaneous intervention (95%). The POCE rate at 1 year was 14% in the overall cohort, with 6.4% all-cause death. In the multivariate analysis, lower POCE rates were found in the groups without MRF (9.4%) and with disease progression (11%) compared with graft/stent failure (17%) and residual disease (18%), hazard ratio 0.67 (95% confidence interval: 0.45-0.99), p = 0.043. At 1 year, the SR group had less chronic persistent angina (19% vs. 34%, p < 0.001), but a higher rate of repeat revascularization (9% vs. 2.9%, p < 0.001). CONCLUSION: MRF was found in 84% of patients with prior revascularization referred for coronary angiography. Stent/graft failure and residual coronary disease were associated with a worse prognosis. SR provided better symptom control at the expense of a higher rate of new revascularization.

6.
Sensors (Basel) ; 23(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37299764

RESUMO

The characterization of suspended dust near the Martian surface is extremely relevant to understand the climate of Mars. In this frame, a Dust Sensor instrument, an infrared device designed to obtain the effective parameters of Martian dust using the scattering properties of the dust particles, was developed. The purpose of this article is to present a novel methodology to calculate, from experimental data, an instrumental function of the Dust Sensor that allows solving the direct problem and providing the signal that this instrument would provide given a distribution of particles. The experimental method is based on recording the signal measured when a Lambertian reflector is gradually introduced into the interaction volume at different distances from the detector and source and applying tomography techniques (inverse Radon transform) to obtain the image of a section of the interaction volume. This method provides a complete mapping of the interaction volume experimentally, which determines the Wf function. The method was applied to solve a specific case study. Among the advantages of this method, it should be noted that it avoids assumptions and idealizations of the dimensions of the volume of interaction and reduces the time required to carry out simulations.


Assuntos
Poeira , Marte , Poeira/análise , Meio Ambiente Extraterreno , Calibragem
7.
Environ Monit Assess ; 195(4): 491, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36943586

RESUMO

This work reports a combined coagulation-electrocoagulation process using a biocoagulant from the Opuntia ficus-indica for treatment of cheese whey wastewater. The process parameters as pH, biocoagulant dosage, and current density were evaluated from the chemometric tools. A Box-Behnken design was used, having as responses the removal percentages of turbidity and chemical oxygen demand (COD). The results showed that for the studied variable ranges, linear models were obtained and the pH was parameter more significant for treatment proposed. The pH showed synergic effect with the investigated parameters, while the biocoagulant dosage and density current showed antagonistic effects. The desirability function was used to optimization of process, and suggested values were pH 10.0, biocoagulant dosage of 4.4 g L-1, and current density of 31.5 mA cm-2, which showed removals of turbidity and COD of 98.9 and 83.8%, respectively.


Assuntos
Queijo , Opuntia , Poluentes Químicos da Água , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Soro do Leite/química , Monitoramento Ambiental , Eletrocoagulação/métodos , Análise da Demanda Biológica de Oxigênio , Resíduos Industriais/análise
8.
An Acad Bras Cienc ; 94(3): e20210191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35857959

RESUMO

This study estimated the potential effects of climate change on peripheral plant diversity by predicting the distribution of species from Cerrado of Northern Brazil. Ecological niche modeling was used to provide present and future projections of responses in terms of occurrence of ten woody species based on four algorithms and four future climate change scenarios for the year 2050. Potential refuge areas for conservation actions were identified, and evidence of the vulnerability of the flora was demonstrated based on the disparity between potential areas of climate stability amid current protected areas. The results suggested a lack of pattern between the scenarios and an idiosyncratic response of the species, indicating different impacts on plant communities and the existence of unequal stable alternative conditions, which could bring consequences to the ecological relationships and functionality of the floras. Even in the most pessimistic scenarios, most species presented an expansion of potential occurrence areas, suppressing or cohabiting with species of adjacent biomes. Typically marginal plants were the most sensitive. Overlapping adequate habitats are concentrated in the NBC. The analysis of habitats in relation to anthropized areas and PAs demonstrate low future effectiveness in the protection of these savannas.


Assuntos
Mudança Climática , Pradaria , Brasil , Ecossistema , Plantas
9.
COPD ; 19(1): 265-273, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35639442

RESUMO

Limited information is available regarding the role of anaerobic metabolism capacity on GOLD 1 and 2 COPD patients during upper limb exercise. We aimed to compare the upper limb anaerobic power capacity, blood lactate concentration, cardiovascular and respiratory responses, in male COPD patients versus healthy subjects during the 30-s Wingate anaerobic test (WAnT). The rate of fatigue and time constant of the power output decay (τ, tau) were also calculated and a regression analysis model was built to assess the predictors of τ in these patients. Twenty-four male COPD patients (post-bronchodilator FEV1 73.2 ± 15.3% of predicted) and 17 healthy subjects (FEV1 103.5 ± 10.1% of predicted) underwent the WAnT. Measurements were performed at rest, at the end of the WAnT, and during 3' and 5' of recovery time. Peak power (p = 0.04), low power (p = 0.002), and mean power output (p = 0.008) were significantly lower in COPD patients than in healthy subjects. Power output decreased exponentially in both groups, but at a significantly faster rate (p = 0.007) in COPD patients. The time constant of power decay was associated with resistance (in ohms) and fat-free mass (r2 = 0.604, adjusted r2 = 0.555, and p = 0.002). Blood lactate concentration was significantly higher in healthy subjects at the end of the test, as well as during 3' and 5' of recovery time (p < 0.01). Compared with healthy subjects, COPD patients with GOLD 1 and 2 presented lower upper limb anaerobic capacity and a faster rate of power output decrease during a maximal intensity exercise. Also, the WAnT proved to be a valid tool to measure the upper limb anaerobic capacity in these patients.


Assuntos
Teste de Esforço , Doença Pulmonar Obstrutiva Crônica , Anaerobiose , Humanos , Ácido Láctico , Masculino , Extremidade Superior
10.
Sensors (Basel) ; 22(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36501918

RESUMO

Suspended dust above the Martian surface is an important element in Martian climatology. In the frame of the Exomars'22 mission, we developed a dust sensor instrument, designed to provide size parameters of dust particles suspended in Mars surface from the light scattered by the particles. Thus, to interpret the data of the dust sensor, we need a method to calculate the theoretical optical power dispersed by the particles and, therefore, the theoretical signal obtained by the instrument. This signal depends on the suspended particles and on the instrument configuration. In this paper, we present a new method to calculate the angular weighting function (Wf) for scattering sensors. Wf encompasses the scattering angles measured by the sensor and depends only on the instrument and not on the suspended particles. To calculate this Wf, we use fundamental radiometry principles and an appropriate coordinate system, where one coordinate is the scattering angle. The method is applied to the dust sensor instrument and compared with other methods. The comparison highlights the advantages of the proposed method since it avoids using an ideal sampling volume, preserves the radiometric meaning, and avoids instrument calibration. The effectiveness of the method makes it a valuable tool for the design of scattering instruments and also for the interpretation of their data.

11.
Monaldi Arch Chest Dis ; 92(4)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35225440

RESUMO

Fall-related causes in patients with COPD might be associated to functional balance impairments and greater disease severity. We aimed to evaluate the reasons for falls in patients with COPD who had presented any fall during the previous year. This is a cross-sectional study. All COPD's GOLD classifications (mild, moderate, severe, and very severe) patients were recruited. In order to participate, patients ought to be clinically stable and without any exacerbation within 30 days prior to study entry. History of falls was self-reported by patients through an interview. Pre and post bronchodilator (salbutamol 400 µg) spirometry was performed. All patients accomplished postural balance tests such as the Berg Balance Scale, Falls Efficacy Scale-International, Time up and Go, Functional Reach test, Tinetti test and Chalder Scale; furthermore, lower limbs muscle strength (muscle dynamometry) and the COPD Assessment Test (CAT) were assessed. Ninety-six patients with COPD were evaluated and divided into two groups stratified according to any positive history of falls in the previous year. Patients with COPD who had any fall in the previous year presented older age (p=0.01), higher BMI (p=0.04) and worse pulmonary function than those who did not fall. The risk of falls was increased in patients with lower muscle strength in the lower limbs (OR 2.9, CI 95%;1.6 to 3.9), age greater than 65 years (OR 2.7, CI 95%;1.3 to 3.4), BMI greater than 28.8 kg/m2 (OR 3.2, CI 95%;1.1 to 5.6), very severe airway obstruction (OR 3.9, CI 95%;2.2 to 3.9) and fatigue (OR 3.2, CI 95%;1.5 to 5.3). Impaired body balance, reduced lower limb strength, disease severity, presence of fatigue and elevated BMI are important factors for falls in patients with COPD.


Assuntos
Acidentes por Quedas , Doença Pulmonar Obstrutiva Crônica , Albuterol , Broncodilatadores , Estudos Transversais , Fadiga/complicações , Humanos , Extremidade Inferior , Força Muscular/fisiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/epidemiologia
12.
J Cardiovasc Pharmacol ; 78(3): 463-473, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34117181

RESUMO

ABSTRACT: The aim of our study is to assess the impact of anemia, chronic kidney disease, and diabetes mellitus on platelet reactivity (PR) in patients with severe aortic stenosis, both at baseline and after transcatheter aortic valve implantation (TAVI). This study is a prespecified subanalysis of the REAC-TAVI prospective, multicenter trial that included patients pretreated with aspirin + clopidogrel before TAVI. PR was measured at baseline and at 5 different time points after TAVI with the VerifyNow assay (Accriva Diagnostics, San Diego, CA), over a 3-month follow-up period. Patients with high PR (HPR) at baseline, before TAVI (n = 48) were randomized to aspirin + clopidogrel or aspirin + ticagrelor for 3 months, whereas those with normal PR (NPR) (n = 20) were continued on aspirin + clopidogrel. A "raiser response" in PR was defined as an increase in PR units >20% of baseline after TAVI. Patients with HPR before TAVI presented concomitant anemia and chronic kidney disease more frequently than their counterparts with NPR. Anemia and higher body mass index were independently associated with HPR to clopidogrel at baseline. Moreover, anemic patients with baseline HPR who were continued on clopidogrel presented higher PR after TAVI than patients with HPR switched to ticagrelor. All patients with baseline NPR presented a "raiser response" after TAVI, which was nonexistent among patients with HPR managed with ticagrelor. In summary, anemia seems as a relevant factor associated with baseline HPR and higher PR after TAVI in patients with baseline HPR randomized to clopidogrel, whereas ticagrelor proved more effective than clopidogrel at attaining sustained reductions in PR during follow-up, regardless of baseline comorbidities.


Assuntos
Estenose da Valva Aórtica/cirurgia , Aspirina/uso terapêutico , Plaquetas/efeitos dos fármacos , Clopidogrel/uso terapêutico , Terapia Antiplaquetária Dupla , Inibidores da Agregação Plaquetária/uso terapêutico , Ticagrelor/uso terapêutico , Substituição da Valva Aórtica Transcateter/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Anemia/sangue , Anemia/epidemiologia , Estenose da Valva Aórtica/sangue , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/epidemiologia , Aspirina/efeitos adversos , Plaquetas/metabolismo , Clopidogrel/efeitos adversos , Comorbidade , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Terapia Antiplaquetária Dupla/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Testes de Função Plaquetária , Prevalência , Estudos Prospectivos , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/epidemiologia , Índice de Gravidade de Doença , Espanha/epidemiologia , Ticagrelor/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
13.
Pathobiology ; 88(2): 170-186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33588418

RESUMO

The immune system plays a critical role in preventing cancer development and progression. However, the complex network of cells and soluble factor that form the tumor microenvironment (TME) can dictate the differentiation of tumor-infiltrating leukocytes and shift the antitumor immune response into promoting tumor growth. With the advent of cancer immunotherapy, there has been a reinvigorated interest in defining how the TME shapes the antitumor immune response. This interest brought to light the microbiome as a novel player in shaping cancer immunosurveillance. Indeed, accumulating evidence now suggests that the microbiome may confer susceptibility or resistance to certain cancers and may influence response to therapeutics, particularly immune checkpoint inhibitors. As we move forward into the age of precision medicine, it is vital that we define the factors that influence the interplay between the triad immune system-microbiota-cancer. This knowledge will contribute to improve the therapeutic response to current approaches and will unravel novel targets for immunotherapy.


Assuntos
Sistema Imunitário/patologia , Microbiota , Neoplasias/imunologia , Animais , Ensaios Clínicos como Assunto , Resistência à Doença , Suscetibilidade a Doenças/microbiologia , Humanos , Imunoterapia/métodos , Camundongos , Neoplasias/patologia , Neoplasias/terapia , Medicina de Precisão , Microambiente Tumoral
14.
Europace ; 23(2): 264-270, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33212484

RESUMO

AIMS: Ablation index (AI) is a marker of lesion quality during catheter ablation that incorporates contact force, time, and power in a weighted formula. This index was originally developed for pulmonary vein isolation as well as other left atrial procedures. The aim of our study is to evaluate the feasibility and efficacy of the AI for the ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical atrial flutter (AFL). METHODS AND RESULTS: This prospective multicentre non-randomized study enrolled 412 consecutive patients with typical AFL undergoing AI-guided cavotricuspid isthmus ablation. The procedure was performed targeting an AI of 500 and an inter-lesion distance measurement of ≤6 mm. The primary endpoints were CTI 'first-pass' block and persistent block after a 20-min waiting time. Secondary endpoints included procedural and radiofrequency duration and fluoroscopic time. A total of 412 consecutive patients were enrolled in 31 centres (mean age 64.9 ± 9.8; 72.1% males and 27.7% with structural heart disease). The CTI bidirectional 'first-pass' block was reached in 355 patients (88.3%), whereas CTI block at the end of the waiting time was achieved in 405 patients (98.3%). Mean procedural, radiofrequency, and fluoroscopic time were 56.5 ± 28.1, 7.8 ± 4.8, and 1.9 ± 4.8 min, respectively. There were no major procedural complications. There was no significant inter-operator variability in the ability to achieve any of the primary endpoints. CONCLUSION: AI-guided ablation with an inter-lesion distance ≤6 mm represents an effective, safe, and highly reproducible strategy to achieve bidirectional block in the treatment of typical AFL.


Assuntos
Flutter Atrial , Ablação por Cateter , Idoso , Flutter Atrial/diagnóstico , Flutter Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia
15.
J Immunol ; 203(9): 2451-2458, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31562208

RESUMO

Granuloma formation is a hallmark of several infectious diseases, including those caused by Mycobacterium sp These structures are composed of accumulations of inflammatory cells, and it has been shown that cytokines such as IFN-γ and TNF-α are required for granuloma assembly during M. avium infections in mice. Macrophages (MΦs) insensitive to IFN-γ (MIIG) mice have MΦs, monocytes, and dendritic cells that are unresponsive to IFN-γ. We observed that although IFN-γ-/- mice present an exacerbated infection, the same is not true for MIIG animals, where the same levels of protection as the wild-type animals were observed in the liver and partial protection in the spleen. Unlike IFN-γ-/- mice, MIIG mice still develop well-defined granulomas, suggesting that IFN-γ-mediated MΦ activation is not required for granuloma assembly. This work also shows that MIIG animals exhibit increased cell recruitment with higher CD4+ T cells numbers as well as increased IFN-γ and TNF-α expression, suggesting that TNF-α may have a role in protection and may compensate the lack of MΦ response to IFN-γ in the MIIG model. TNF-α-deficient MIIG mice (MIIG.TNF-α-/-) exhibited increased bacterial burdens when compared with MIIG mice. These results suggest that in the absence of IFN-γ signaling in MΦs, TNF-α has a protective role against M. avium.


Assuntos
Interferon gama/fisiologia , Ativação de Macrófagos/imunologia , Mycobacterium avium/imunologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Linfócitos T CD4-Positivos/fisiologia , Granuloma/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
16.
Sensors (Basel) ; 21(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34640826

RESUMO

The need to monitor specific areas for different applications requires high spatial and temporal resolution. This need has led to the proliferation of ad hoc systems on board nanosatellites, drones, etc. These systems require low cost, low power consumption, and low weight. The work we present follows this trend. Specifically, this article evaluates a method to determine the cloud map from the images provided by a simple bi-spectral infrared camera within the framework of JEM-EUSO (The Joint Experiment Missions-Extrem Universe Space Observatory). This program involves different experiments whose aim is determining properties of Ultra-High Energy Cosmic Ray (UHECR) via the detection of atmospheric fluorescence light. Since some of those projects use UV instruments on board space platforms, they require knowledge of the cloudiness state in the FoV of the instrument. For that reason, some systems will include an infrared (IR) camera. This study presents a test to generate a binary cloudiness mask (CM) over the ocean, employing bi-spectral IR data. The database is created from Moderate-Resolution Imaging Spectroradiometer (MODIS) data (bands 31 and 32). The CM is based on a split-window algorithm. It uses an estimation of the brightness temperature calculated from a statistical study of an IR images database along with an ancillary sea surface temperature. This statistical procedure to obtain the estimate of the brightness temperature is one of the novel contributions of this work. The difference between the measured and estimation of the brightness temperature determines whether a pixel is cover or clear. That classification requires defining several thresholds which depend on the scenarios. The procedure for determining those thresholds is also novel. Then, the results of the algorithm are compared with the MODIS CM. The agreement is above 90%. The performance of the proposed CM is similar to that of other studies. The validation also shows that cloud edges concentrate the vast majority of discrepancies with the MODIS CM. The relatively high accuracy of the algorithm is a relevant result for the JEM-EUSO program. Further work will combine the proposed algorithm with complementary studies in the framework of JEM-EUSO to reinforce the CM above the cloud edges.

17.
J Environ Manage ; 282: 111528, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33172704

RESUMO

The study of the relationships between freshwater organisms, pollution and public awareness has been little researched. The public's perception of risk from pollution is a fundamental component in determining consumer behavior and promoting healthy habits. For instance, understanding how consumers perceive the risks associated with pollution can help with adoption of safe behaviors to reduce the health hazard associated with pollutant exposure. This study focused on the southeastern United States, a region predicted to be exposed to high mercury stress by increasing mercury deposition and methylation. First, we placed our study region in the world map of regions more prone to suffer from increasing mercury stress in a climate change scenario. Second, mercury levels in fish tissues was quantified by direct mercury analyzer (DMA). Third, we explored human fish consumption habits and risk social perception, including willingness to adapt fish consumption based on two future hypothetical scenarios of mercury stress. From a global perspective, our analysis demonstrates that the southern US is one of five world areas of greatest conservation concern for mercury stress. In this region, the average mono-methyl mercury concentration in fish tissues exceeded the limits considered safe for human consumption. Even though many in the local population were aware of the health hazards associated with fish consumption, only women of reproductive age were willing to adopt safe consumption habits. Altogether, these results show how bringing together field data, social perceptions, and consumption habits can help in designing an adaptive strategy to confront mercury pollution. Although our results are for the United States, other world regions prone to suffer increasing mercury stress have been identified and should be the focus of future studies and prescriptions.


Assuntos
Mercúrio , Animais , Feminino , Peixes , Contaminação de Alimentos/análise , Humanos , Mercúrio/análise , Percepção Social , Sudeste dos Estados Unidos , Estados Unidos
18.
Immunology ; 159(1): 121-129, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606895

RESUMO

The transcription factor hypoxia-inducible factor-1 alpha (HIF-1α) is a key regulator of the response and function of myeloid cells in hypoxic and inflammatory microenvironments. To define the role of HIF-1α in tuberculosis, the progression of aerosol Mycobacterium tuberculosis infection was analysed in mice deficient in HIF-1α in the myeloid lineage (mHIF-1α-/- ). We show that myeloid HIF-1α is not required for the containment of the infection, as both wild-type (WT) and mHIF-1α-/- mice mounted normal Th1 responses and maintained control of bacterial growth throughout infection. However, during chronic infection mHIF-1α-/- mice developed extensive lymphocytic inflammatory involvement of the interstitial lung tissue and died earlier than WT mice. These data support the hypothesis that HIF-1α activity coordinates the response of myeloid cells during M. tuberculosis infection to prevent excessive leucocyte recruitment and immunopathological consequences to the host.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Pulmão/metabolismo , Mycobacterium tuberculosis/crescimento & desenvolvimento , Células Mieloides/metabolismo , Pneumonia/metabolismo , Tuberculose Pulmonar/metabolismo , Animais , Carga Bacteriana , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Interações Hospedeiro-Patógeno , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Pulmão/imunologia , Pulmão/microbiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mycobacterium tuberculosis/imunologia , Células Mieloides/imunologia , Células Mieloides/microbiologia , Pneumonia/genética , Pneumonia/imunologia , Pneumonia/microbiologia , Transdução de Sinais , Tuberculose Pulmonar/genética , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia
19.
Plant Cell Physiol ; 61(7): 1348-1364, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32384163

RESUMO

Pollen lipids are essential for sexual reproduction, but our current knowledge regarding lipid dynamics in growing pollen tubes is still very scarce. Here, we report unique lipid composition and associated gene expression patterns during olive pollen germination. Up to 376 genes involved in the biosynthesis of all lipid classes, except suberin, cutin and lipopolysaccharides, are expressed in olive pollen. The fatty acid profile of olive pollen is markedly different compared with other plant organs. Triacylglycerol (TAG), containing mostly C12-C16 saturated fatty acids, constitutes the bulk of olive pollen lipids. These compounds are partially mobilized, and the released fatty acids enter the ß-oxidation pathway to yield acetyl-CoA, which is converted into sugars through the glyoxylate cycle during the course of pollen germination. Our data suggest that fatty acids are synthesized de novo and incorporated into glycerolipids by the 'eukaryotic pathway' in elongating pollen tubes. Phosphatidic acid is synthesized de novo in the endomembrane system during pollen germination and seems to have a central role in pollen tube lipid metabolism. The coordinated action of fatty acid desaturases FAD2-3 and FAD3B might explain the increase in linoleic and alpha-linolenic acids observed in germinating pollen. Continuous synthesis of TAG by the action of diacylglycerol acyltransferase 1 (DGAT1) enzyme, but not phosphoplipid:diacylglycerol acyltransferase (PDAT), also seems plausible. All these data allow for a better understanding of lipid metabolism during the olive reproductive process, which can impact, in the future, on the increase in olive fruit yield and, therefore, olive oil production.


Assuntos
Germinação , Metabolismo dos Lipídeos , Olea/metabolismo , Tubo Polínico/crescimento & desenvolvimento , Pólen/crescimento & desenvolvimento , Transcriptoma , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glioxilatos/metabolismo
20.
Clin Auton Res ; 30(2): 157-164, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31938978

RESUMO

PURPOSE: Chronic obstructive pulmonary disease (COPD) negatively impacts autonomic control of the heart rate, as assessed by time and frequency domains of heart rate variability (HRV) analysis. However, it is unknown whether symbolic dynamic analysis may identify cardiac autonomic impairment, and whether such nonlinear indices may be associated with disease severity, prognostic markers, perceived dyspnea and functional capacity in patients with COPD. The current study assessed cardiac autonomic modulation by symbolic analysis of HRV in patients with COPD compared with healthy controls. METHODS: We recruited 54 COPD patients and 20 healthy controls. The interval between two successive R-wave peaks was calculated in the resting supine position. HRV was analyzed using symbolic markers and Shannon entropy (SE). The six-minute walk test (6MWT) was applied in a 30-m corridor. RESULTS: We found a lower 6MWT distance in patients with COPD compared with healthy controls (p < 0.05). We found increased SE and decreased percentage of no variation patterns (0V%) in COPD patients compared with the control group (p = 0.001). Significant correlations were found between the percentage of one variation pattern (1V%) and the Medical Research Council dyspnea scale (r = 0.38, p = 0.01), BODE index (r = 0.38, p = 0.01), forced expiratory volume in the first second (FEV1) [L] (r = -0.44, p = 0.003) and FEV1 [%] (r = -0.35, p = 0.02). It was found that SE was inversely associated with 0V% (r = -0.87, p < 0.0001). CONCLUSION: COPD patients present with depressed sympathetic modulation of HR and higher SE compared with healthy controls. This increased irregularity was inversely associated with 0V%. These results suggested that COPD patients seem to have a cardiac control shifted towards a parasympathetic predominance compared with controls. Symbolic dynamic and complexity index of HRV are related to disease severity, symptoms and functional impairment in these patients.


Assuntos
Frequência Cardíaca/fisiologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Índice de Gravidade de Doença , Análise de Sistemas , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia/métodos , Teste de Esforço/métodos , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória/métodos , Teste de Caminhada/métodos
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