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1.
Am J Physiol Heart Circ Physiol ; 326(3): H623-H635, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38133617

RESUMEN

Pulmonary hypertension (PH) consists of a heterogenous group of diseases that culminate in increased pulmonary arterial pressure and right ventricular (RV) dysfunction. We sought to investigate the role of FXYD1, a small membrane protein that modulates Na+-K+-ATPase function, in the pathophysiology of PH. We mined online transcriptome databases to assess FXYD1 expression in PH. We characterized the effects of FXYD1 knockout (KO) in mice on right and left ventricular (RV and LV) function using echocardiography and measured invasive hemodynamic measurements under normal conditions and after treatment with bleomycin sulfate or chronic hypoxia to induce PH. Using immunohistochemistry, immunoblotting, and functional assays, we examined the effects of FXYD1 KO on pulmonary microvasculature and RV and LV structure and assessed signaling via endothelial nitric oxide synthase (eNOS) and inflammatory pathways. FXYD1 lung expression tended to be lower in samples from patients with idiopathic pulmonary arterial hypertension (IPAH) compared with controls, supporting a potential pathophysiological role. FXYD1 KO mice displayed characteristics of PH including significant increases in pulmonary arterial pressure, increased muscularization of small pulmonary arterioles, and impaired RV systolic function, in addition to LV systolic dysfunction. However, when PH was stimulated with standard models of lung injury-induced PH, there was no exacerbation of disease in FXYD1 KO mice. Both the lungs and left ventricles exhibited elevated nitrosative stress and inflammatory milieu. The absence of FXYD1 in mice results in LV inflammation and cardiopulmonary redox signaling changes that predispose to pathophysiological features of PH, suggesting FXYD1 may be protective.NEW & NOTEWORTHY This is the first study to show that deficiency of the FXYD1 protein is associated with pulmonary hypertension. FXYD1 expression is lower in the lungs of people with idiopathic pulmonary artery hypertension. FXYD1 deficiency results in both left and right ventricular functional impairment. Finally, FXYD1 may endogenously protect the heart from oxidative and inflammatory injury.


Asunto(s)
Insuficiencia Cardíaca , Hipertensión Pulmonar , Proteínas de la Membrana , Fosfoproteínas , Disfunción Ventricular Derecha , Animales , Humanos , Ratones , Ventrículos Cardíacos , Hipertensión Pulmonar/metabolismo , Pulmón/metabolismo , Oxidación-Reducción , Arteria Pulmonar , Función Ventricular Derecha , Proteínas de la Membrana/metabolismo , Fosfoproteínas/metabolismo
2.
J Am Heart Assoc ; 11(23): e018353, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36382959

RESUMEN

Background To date, assessment of right ventricular (RV) function in mice has relied extensively on invasive measurements. Echocardiographic advances have allowed adaptation of measures used in humans for serial, noninvasive RV functional assessment in mice. We evaluated the diagnostic performance of tricuspid annular plane systolic excursion (TAPSE), RV peak systolic myocardial velocity (s'), RV myocardial performance index (MPI), and RV fractional area change (FAC) in a mouse model of pulmonary hypertension. Methods and Results Echocardiography was performed on mice at baseline and 3 weeks after induction of pulmonary hypertension using inhaled bleomycin or saline, including adapted measures of TAPSE, s', MPI, and FAC. RV systolic pressure was measured by invasive catheterization, and RV contractility was measured as the peak slope of the RV systolic pressure recording (maximum change pressure/change time). Postmortem morphological assessment of RV hypertrophy was performed. RV systolic pressure was elevated and maximum change pressure/change time was reduced in bleomycin versus control (n=8; P=0.002). Compared with controls, bleomycin mice had reduced TAPSE (0.79±0.05 versus 1.06±0.04 mm; P=0.003), s' (21.3±1.2 versus 29.2±1.3 mm/s; P<0.001), and FAC (20.3±0.7% versus 31.0±1.3%; P<0.001), whereas MPI was increased (0.51±0.03 versus 0.37±0.01; P=0.006). All measures correlated with RV systolic pressure and maximum change pressure/change time. Intraobserver and interobserver variability were minimal. Receiver operating characteristic curves demonstrated that TAPSE (<0.84 mm), s'(<23.3 mm/s), MPI (0.42), and FAC (<23.3%) identified maximum change pressure/change time ≤2100 mm Hg/s with high accuracy. Conclusions TAPSE, s', MPI, and FAC are measurable consistently using high-resolution echocardiography in mice, and are sensitive and specific measures of pulmonary pressure and RV function. This validation opens the opportunity for serial noninvasive measures in mouse models of pulmonary hypertension, enhancing the statistical power of preclinical studies of novel therapeutics.


Asunto(s)
Hipertensión Pulmonar , Fibrosis Pulmonar , Humanos , Ratones , Animales , Hipertensión Pulmonar/diagnóstico por imagen , Hipertensión Pulmonar/etiología , Presión Arterial , Autopsia , Ecocardiografía
3.
Clin Chim Acta ; 537: 87-95, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36279940

RESUMEN

BACKGROUND: The objective of our study was to evaluate a single blood collection tube with a novel antithrombotic formulation to measure both hematological, biochemical, and d-dimer analytes. METHODS: Paired samples of gold standard blood tubes (EDTA, lithium heparin, sodium citrate) and a new antithrombotic formulation blood tube were collected from 187 patients. The new antithrombotic tube is a lithium heparin tube preloaded with a liquid form of prostacyclin analog. The novel tube was tested on seventeen hematological parameters and smears against EDTA, on fourteen biochemical parameters against lithium heparin and on d-dimer against sodium citrate. RESULTS: All correlation coefficients were close to 0.99. The Bland-Altman analyses presented a satisfactory correspondence for all analytes. All the hematological examinations demonstrated comparable results between EDTA and the novel formulation, except for platelet counts analyzed by impedance method, but not by fluorescence. We detected lower mean platelet volume with/without outliers (5.06%)/(5.13%) in the novel formulation and increased mean corpuscular hemoglobin concentration (2.55%). All the biochemistry analytes demonstrated comparable results between lithium heparin and the novel tube. d-dimer showed comparable results between citrated blood and the novel formulation after dilution correction. CONCLUSIONS: We describe a novel antithrombotic formulation tube with the potential to be introduced into clinical laboratories for simultaneous analysis of thirty-two blood analytes.


Asunto(s)
Heparina , Iloprost , Humanos , Fibrinolíticos , Litio , Ácido Edético , Recolección de Muestras de Sangre/métodos , Citrato de Sodio
4.
Biomed Microdevices ; 13(2): 383-92, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21207149

RESUMEN

We present a hybrid chip of polymer and stainless steel designed for high-throughput continuous electroporation of cells in suspension. The chip is constructed with two parallel stainless steel mesh electrodes oriented perpendicular to the liquid flow. The relatively high hydrodynamic resistance of the micrometer sized holes in the meshes compared to the main channel enforces an almost homogeneous flow velocity between the meshes. Thereby, very uniform electroporation of the cells can be accomplished. Successful electroporation of 20 million human dendritic cells with mRNA is demonstrated. The performance of the chip is similar to that of the traditional electroporation cuvette, but without an upper limit on the number of cells to be electroporated. The device is constructed with two female Luer parts and can easily be integrated with other microfluidic components. Furthermore it is fabricated from injection molded polymer parts and commercially available stainless steel mesh, making it suitable for inexpensive mass production.


Asunto(s)
Células Dendríticas/citología , Equipos Desechables , Electroporación/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Polímeros/química , Células Dendríticas/metabolismo , Proteínas Fluorescentes Verdes/genética , Humanos , Cinética , ARN Mensajero/metabolismo , Reproducibilidad de los Resultados , Acero Inoxidable/química , Transfección
5.
Langmuir ; 26(20): 16171-7, 2010 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-20860406

RESUMEN

Complex one- or two-dimensional concentration gradients of alkynated molecules are produced on azidized conducting polymer substrates by stenciled "electro click chemistry". The latter describes the local electrochemical generation of catalytically active Cu(I) required to complete a "click reaction" between alkynes and azides at room temperature. A stencil on the counter electrode defines the shape and multiplicity of the gradient(s) on the conducting polymer substrate, while the specific reaction conditions control gradient steepness and the maximum concentration deposited. Biologically active ligands including cell binding peptides are patterned in gradients by this method without losing their biological function or the conductivity of the polymer.


Asunto(s)
Química Clic , Conductividad Eléctrica , Alquinos/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Cobre/química , Electrodos , Proteínas Inmovilizadas/química , Níquel/química , Ácido Nitrilotriacético/química , Oligopéptidos/química , Espectroscopía de Fotoelectrones , Polímeros/química , Propiedades de Superficie
6.
J Phys Chem A ; 113(34): 9450-7, 2009 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-19645430

RESUMEN

The detection of analyte-binding events by receptors is drawing together the fields of Raman spectroscopy and supramolecular chemistry. This study is intended to facilitate this cohering by examining a model in the solution phase. The resonance Raman scattering (RRS) spectra of the complexation between tetrathiafulvalene (TTF) and cyclobis(paraquat-p-phenylene) (CBPQT(4+)) has been used as the model system to characterize the binding event of a host-guest system. RRS spectra are generated by excitation (lambda(exc) = 785 nm) within the lowest-energy charge-transfer (CT) transition (lambda(max) = 865 nm) of the TTF subsetCBPQT(4+) complex. The paired binding curves from the RRS and UV-vis-NIR titration data agrees with prior work, and a DeltaG of -5.7 +/- 0.6 kcal mol(-1) (MeCN, 298 K) was obtained for the complexation of TTF with CBPQT(4+). Computations on the complex and its components reproduce the energy shifts and resonance enhancements of the Raman band intensities, providing a basis to identify the structural and vibrational changes occurring upon complexation. The changes in bond lengths coincide with partial depopulation of a TTF-based HOMO and population of a CBPQT(4+)-based LUMO through CT mixing in the ground state of 0.46e(-). The structural changes upon complexation generally lead to lower wavenumber vibrations and to changes in the normal mode descriptions.

7.
Bioresour Technol ; 161: 78-83, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24686374

RESUMEN

An isolated, solvent-extracted lignin from candlenut (Aleurites moluccana) biomass was subjected to catalytic depolymerization in the presence of supercritical methanol, using a range of porous metal oxides derived from hydrotalcite-like precursors. The most effective catalysts in terms of lignin conversion to methanol-soluble products, without char formation, were based on copper in combination with other dopants based on relatively earth-abundant metals. Nearly complete conversion of lignin to bio-oil composed of monomers and low-mass oligomers with high aromatic content was obtained in 6h at 310°C using a catalyst based on a Cu- and La-doped hydrotalcite-like precursor. Product mixtures were characterized by NMR spectroscopy, gel permeation chromatography, and GC-MS.


Asunto(s)
Cobre/química , Lignina/química , Metanol/química , Óxidos/química , Catálisis , Euphorbiaceae , Lignina/aislamiento & purificación
9.
Carbohydr Res ; 344(18): 2568-72, 2009 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-19850284

RESUMEN

Studies on the HCl-catalysed microwave-assisted dehydration of highly concentrated aqueous fructose (27 wt%) to 5-hydroxymethylfurfural (HMF) revealed a significant increase in the fructose conversion rate over the conventional heated systems. Water, being the most benign solvent and therefore ideal for green and sustainable chemistry, normally is a poor solvent for the dehydration process resulting in low HMF selectivities and yields. However, reaction at 200 degrees C with microwave irradiation with a short reaction time of only 1s resulted in good HMF selectivity of 63% and fructose conversion of 52%, while prolonged irradiation for 60s (or more) resulted in nearly full fructose conversion (95%) but lower HMF yield (53%). Decreasing the fructose concentration significantly improved the HMF selectivity, but possibly made the production route less attractive from an industrial point of view due to the resultant low throughput.


Asunto(s)
Fructosa/química , Furaldehído/análogos & derivados , Desecación , Furaldehído/síntesis química , Tecnología Química Verde , Microondas , Temperatura , Agua
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