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1.
Talanta ; 269: 125482, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042146

RESUMO

Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy is an emerging technology in the medical field. Blood D-dimer was initially studied as a marker of the activation of coagulation and fibrinolysis. It is mainly used as a potential diagnosis screening test for pulmonary embolism or deep vein thrombosis but was recently associated with COVID-19 severity. This study aimed to evaluate the use of ATR-FTIR spectroscopy with machine learning to classify plasma D-dimer concentrations. The plasma ATR-FTIR spectra from 100 patients were studied through principal component analysis (PCA) and two supervised approaches: genetic algorithm with linear discriminant analysis (GA-LDA) and partial least squares with linear discriminant (PLS-DA). The spectra were truncated to the fingerprint region (1800-1000 cm-1). The GA-LDA method effectively classified patients according to D-dimer cutoff (≤0.5 µg/mL and >0.5 µg/mL) with 87.5 % specificity and 100 % sensitivity on the training set, and 85.7 % specificity, and 95.6 % sensitivity on the test set. Thus, we demonstrate that ATR-FTIR spectroscopy might be an important additional tool for classifying patients according to D-dimer values. ATR-FTIR spectral analyses associated with clinical evidence can contribute to a faster and more accurate medical diagnosis, reduce patient morbidity, and save resources and demand for professionals.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Fourier , Análise Discriminante , Análise de Componente Principal , Proteínas Mutadas de Ataxia Telangiectasia
2.
Cell Biol Int ; 43(8): 890-898, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31062893

RESUMO

The present study aimed to test the hypothesis that increased sodium concentration affects the migratory phenotype of vascular smooth muscle cells (VSMCs) independently of the haemodynamic factors. Cell migration was evaluated by wound-healing assay under the following conditions: high sodium (HS, 160 mM) and control (CT, 140 mM). Cell viability was assessed by annexin V and propidium iodide labeling. Cyclooxygenase-2 (COX-2) gene expression was analysed by reverse transcription polymerase chain reaction. ERK1/2 phosphorylation was assessed by western blot. Exposure of VSMCs to HS reduced migration, and AT1R blockade prevented this response. HS increased COX-2 gene expression, and COX-2 blockade prevented the reduction in VSMC migration induced by HS. HS also increased ERK1/2 phosphorylation, and ERK1/2 inhibition recovered VSMC migration as well as blocked COX-2 gene expression. The TXA2 receptor blocker, but not the prostacyclin receptor blocker, prevented the HS-induced VSMCs migration decrease. HS reduces the migration of VSMCs by increasing COX-2 gene expression via AT1R-ERK1/2 phosphorylation. In addition, increased COX-2 by HS seems to modulate the reduction of VSMCs migration by the TXA2 receptor.


Assuntos
Movimento Celular/efeitos dos fármacos , Músculo Liso Vascular , Miócitos de Músculo Liso/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Sódio/farmacologia , Animais , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/citologia , Receptores de Tromboxano A2 e Prostaglandina H2/metabolismo , Sódio/química
3.
Cell Physiol Biochem ; 44(5): 1796-1809, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29216624

RESUMO

BACKGROUND/AIMS: The atherosclerotic apolipoprotein E-deficient (apoE-/-) mouse exhibits impaired vasodilation and enhanced vasoconstriction responsiveness. The objectives of this study were: a) to determine the relative contribution of cyclooxygenases (Cox-1 and Cox-2), thromboxane A2 (TXA2) and endothelin-1 (ET-1) to enhancing vascular hyperresponsiveness in this model of atherosclerosis and b) to investigate the beneficial effects of the phosphodiesterase 5 inhibitor sildenafil on this endothelial dysfunction. METHODS: Adult male apoE-/- mice were treated with sildenafil (40 mg/kg/day, for 3 weeks) and compared with non-treated ApoE-/- and wild-type mice. The beneficial effects of sildenafil on vascular contractile response to phenylephrine (PE) in aortic rings were evaluated before and after incubation with Cox-1 (SC-560) or Cox-2 (NS-398) inhibitors or the TP antagonist SQ-29548, and on contractile responsiveness to ET-1. RESULTS: ApoE-/- mice exhibited enhanced vasoconstriction to PE (Rmax ∼35%, p<0.01), which was prevented by treatment with sildenafil. The enhanced PE-induced contractions were abolished by both Cox-1 inhibition and TP antagonist, but were not modified by Cox-2 inhibition. Aortic rings from ApoE-/- mice also exhibited enhanced contractions to ET-1 (Rmax ∼30%, p<0.01), which were attenuated in sildenafil-treated ApoE-/- mice. In addition, we observed augmented levels of vascular proinflammatory cytokines in ApoE-/- mice, which were partially corrected by treatment with sildenafil (IL-6, IL-10/IL-6 ratio and MCP-1). CONCLUSION: The present data show that the Cox-1/TXA2 pathway prevails over the Cox-2 isoform in the mediation of vascular hypercontractility observed in apoE-/-mice. The results also show a beneficial effect of sildenafil on this endothelial dysfunction and on the proinflammatory cytokines in atherosclerotic animals, opening new perspectives for the treatment of other endothelium-related cardiovascular abnormalities.


Assuntos
Apolipoproteínas E/genética , Ciclo-Oxigenase 1/metabolismo , Citrato de Sildenafila/farmacologia , Tromboxano A2/metabolismo , Vasoconstrição/efeitos dos fármacos , Animais , Apolipoproteínas E/deficiência , Compostos Bicíclicos Heterocíclicos com Pontes , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Ácidos Graxos Insaturados , Hidrazinas/farmacologia , Interleucina-10/análise , Interleucina-6/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nitrobenzenos/farmacologia , Fenilefrina/farmacologia , Pirazóis/farmacologia , Receptores de Tromboxanos/antagonistas & inibidores , Receptores de Tromboxanos/metabolismo , Sulfonamidas/farmacologia
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