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Superoxide dismutase 2 (SOD2) catalyzes the dismutation of superoxide to hydrogen peroxide in mitochondria, limiting mitochondrial damage. The SOD2 amino acid valine-to-alanine substitution at position 16 (V16A) in the mitochondrial leader sequence is a common genetic variant among patients with sickle cell disease (SCD). However, little is known about the cardiovascular consequences of SOD2V16A in SCD patients or its impact on endothelial cell function. Here, we show SOD2V16A associates with increased tricuspid regurgitant velocity (TRV), systolic blood pressure, right ventricle area at systole, and declined 6-minute walk distance in 410 SCD patients. Plasma lactate dehydrogenase, a marker of oxidative stress and hemolysis, significantly associated with higher TRV. To define the impact of SOD2V16A in the endothelium, we introduced the SOD2V16A variant into endothelial cells. SOD2V16A increases hydrogen peroxide and mitochondrial reactive oxygen species (ROS) production compared with controls. Unexpectedly, the increased ROS was not due to SOD2V16A mislocalization but was associated with mitochondrial complex IV and a concomitant decrease in basal respiration and complex IV activity. In sum, SOD2V16A is a novel clinical biomarker of cardiovascular dysfunction in SCD patients through its ability to decrease mitochondrial complex IV activity and amplify ROS production in the endothelium.
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Anemia de Células Falciformes , Células Endoteliales , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/metabolismo , Células Endoteliales/metabolismo , Humanos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismoRESUMEN
THE QUESTION ADDRESSED BY THE STUDY: Good biological indicators capable of predicting chronic obstructive pulmonary disease (COPD) phenotypes and clinical trajectories are lacking. Because nuclear and mitochondrial genomes are damaged and released by cigarette smoke exposure, plasma cell-free mitochondrial and nuclear DNA (cf-mtDNA and cf-nDNA) levels could potentially integrate disease physiology and clinical phenotypes in COPD. This study aimed to determine whether plasma cf-mtDNA and cf-nDNA levels are associated with COPD disease severity, exacerbations, and mortality risk. MATERIALS AND METHODS: We quantified mtDNA and nDNA copy numbers in plasma from participants enrolled in the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE, n = 2,702) study and determined associations with relevant clinical parameters. RESULTS: Of the 2,128 participants with COPD, 65% were male and the median age was 64 (interquartile range, 59-69) years. During the baseline visit, cf-mtDNA levels positively correlated with future exacerbation rates in subjects with mild/moderate and severe disease (Global Initiative for Obstructive Lung Disease [GOLD] I/II and III, respectively) or with high eosinophil count (≥ 300). cf-nDNA positively associated with an increased mortality risk (hazard ratio, 1.33 [95% confidence interval, 1.01-1.74] per each natural log of cf-nDNA copy number). Additional analysis revealed that individuals with low cf-mtDNA and high cf-nDNA abundance further increased the mortality risk (hazard ratio, 1.62 [95% confidence interval, 1.16-2.25] per each natural log of cf-nDNA copy number). ANSWER TO THE QUESTION: Plasma cf-mtDNA and cf-nDNA, when integrated into quantitative clinical measurements, may aid in improving COPD severity and progression assessment.
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Ácidos Nucleicos Libres de Células , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Masculino , Persona de Mediana Edad , Femenino , Ácidos Nucleicos Libres de Células/genética , ADN Mitocondrial , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/genética , Biomarcadores , Fenotipo , Progresión de la EnfermedadRESUMEN
OBJECTIVE: Due to the high clinical heterogeneity of epilepsy, there is a critical need for novel metrics aimed at capturing its biological and phenotypic complexity. Frailty is increasingly recognized in various medical disciplines as a useful construct to understand differences in susceptibility to adverse outcomes. Here, we develop a frailty index (FI) for patients with epilepsy (PwE) and explore its association with demographic and clinical features. METHODS: In this cross-sectional study, we consecutively enrolled 153 PwE from an outpatient epilepsy clinic. Participants were assessed for various health deficits to calculate the FI. Associations between FI and demographic/clinical features, antiseizure medications (ASMs), and patient-reported outcomes were analyzed using general linear models and Spearman correlation. RESULTS: The median age at the time of study visit was 47 years (interquartile range = 33-60), and 89 (58.2%) patients were females. Multiple linear regression revealed that the developed 33-item FI showed an independent association with age, female sex, higher body mass index, family history of epilepsy, intellectual disability, and the number of ASMs used. A robust analysis of covariance showed higher FI levels in patients using cytochrome P450 3A4-inducer ASMs. We found a moderate positive correlation between FI and psychological distress, lower quality of life, and physical frailty, measured by the Hospital Anxiety and Depression Scale, Quality of Life in Epilepsy Inventory-10, and handgrip strength, respectively. Finally, a weak association was observed between higher FI scores and an increased number of epileptic falls. SIGNIFICANCE: This study highlights the significance of frailty as a comprehensive health measure in epilepsy. It suggests that frailty in this specific population is not only a manifestation of aging but is inherently linked to epilepsy and treatment-related factors. Future research is warranted to validate and refine the FI in diverse epilepsy populations and investigate its impact on specific adverse outcomes in longitudinal studies.
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Anticonvulsivantes , Epilepsia , Fragilidad , Humanos , Masculino , Femenino , Estudios Transversales , Fragilidad/diagnóstico , Persona de Mediana Edad , Epilepsia/tratamiento farmacológico , Epilepsia/diagnóstico , Adulto , Anticonvulsivantes/uso terapéutico , Calidad de Vida , Convulsiones/tratamiento farmacológico , AncianoRESUMEN
Solid-state light-emitting diodes (LEDs) emit nearly monochromatic light, yet seamless tuning of emission color throughout the visible region remains elusive. Color-converting powder phosphors are therefore used for making LEDs with a bespoke emission spectrum, yet broad emission lines and low absorption coefficients compromise the formation of small-footprint monochromatic LEDs. Color conversion by quantum dots (QDs) can address these issues, but high-performance monochromatic LEDs made using QDs free of restricted, hazardous elements remain to be demonstrated. Here, we show green, amber, and red LEDs formed using InP-based QDs as on-chip color convertor for blue LEDs. Implementing QDs with near-unity photoluminescence efficiency yields a color conversion efficiency over 50% with little intensity roll-off and nearly complete blue light rejection. Moreover, as the conversion efficiency is mostly limited by package losses, we conclude that on-chip color conversion using InP-based QDs can provide spectrum-on-demand LEDs, including monochromatic LEDs that bridge the green gap.
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A reaction in anhydrous toluene between the formally unsaturated fragment [Ln(hfac)3] (Ln3+ = Eu3+, Gd3+ and Er3+; Hhfac = hexafluoroacetylacetone) and [Al(qNO)3] (HqNO = 8-hydroxyquinoline N-oxide), here prepared for the first time from [Al(OtBu)3] and HqNO, affords the dinuclear heterometallic compounds [Ln(hfac)3Al(qNO)3] (Ln3+ = Eu3+, Gd3+ and Er3+) in high yields. The molecular structures of these new compounds revealed a dinuclear species with three phenolic oxygen atoms bridging the two metal atoms. While the europium and gadolinium complexes show the coordination number (CN) 9 for the lanthanide centre, in the complex featuring the smaller erbium ion, only two oxygens bridge the two metal atoms for a resulting CN of 8. The reaction of [Eu(hfac)3] with [Alq3] (Hq = 8-hydroxyquinoline) in the same conditions yields a heterometallic product of composition [Eu(hfac)3Alq3]. A recrystallization attempt from hot heptane in air produced single crystals of two different morphologies and compositions: [Eu2(hfac)6Al2q4(OH)2] and [Eu2(hfac)6(µ-Hq)2]. The latter compound can be directly prepared from [Eu(hfac)3] and Hq at room temperature. Quantum mechanical calculations confirm (i) the higher stability of [Eu(hfac)3Al(qNO)3] vs. the corresponding [Eu(hfac)3Alq3] and (ii) the preference of the Er complexes for the CN 8, justifying the different behaviour in terms of the Lewis acidity of the metal centre.
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Background: Penile Mondor's disease (PMD) is a rare syndrome characterized by sclerosis after superficial thrombophlebitis of the superficial penile veins. The most usual appearance of PMD is a tender, palpable, painful, and sometimes visible cord on the dorsal surface of the penis. Its pathogenesis is still unclear, and a standardized treatment has not been established. Case report: A 54-year-old male patient presented with a left-sided indirect reducible inguinal hernia. The patient underwent Lichtenstein's procedure for inguinal hernia repair. On the tenth postoperative day, he returned with PMD confirmed by Doppler ultrasonography examination. Treatment with 4000 UI low molecular weight heparin (LMWH) daily for three weeks resolved the symptoms, but mild venous ectasia just to the proximal part of the penis remained. Discussion: The exact cause of PMD is not well understood, but various studies have identified certain factors associated with an increased risk of the condition. Out of various potential factors that could trigger PMD, the repair of an inguinal hernia has been reported only once. Treatment may involve pain management, anti-inflammatory medications, anticoagulants, and, in some cases, surgery. Conclusion: PMD after open hernia repair surgery is a very rare benign condition. Correct diagnosis and prompt treatment allowed symptom resolution. Residual venous ectasia has no clinical significance other than a cosmetic appearance.
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Background: Penile Mondor's disease (PMD) is a rare syndrome characterized by sclerosis after superficial thrombophlebitis of the superficial penile veins. The most usual appearance of PMD is a tender, palpable, painful, and sometimes visible cord on the dorsal surface of the penis. Its pathogenesis is still unclear, and a standardized treatment has not been established. Case report: A 54-year-old male patient presented with a left-sided indirect reducible inguinal hernia. The patient underwent Lichtenstein's procedure for inguinal hernia repair. On the tenth postoperative day, he returned with PMD confirmed by Doppler ultrasonography examination. Treatment with 4000 UI low molecular weight heparin (LMWH) daily for three weeks resolved the symptoms, but mild venous ectasia just to the proximal part of the penis remained. Discussion: The exact cause of PMD is not well understood, but various studies have identified certain factors associated with an increased risk of the condition. Out of various potential factors that could trigger PMD, the repair of an inguinal hernia has been reported only once. Treatment may involve pain management, anti-inflammatory medications, anticoagulants, and, in some cases, surgery. Conclusion: PMD after open hernia repair surgery is a very rare benign condition. Correct diagnosis and prompt treatment allowed symptom resolution. Residual venous ectasia has no clinical significance other than a cosmetic appearance.
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We studied the formation of zinc selenide (ZnSe) from zinc chloride (ZnCl2) and trioctylphosphine selenide (TOP=Se) in oleylamine, a chemistry originally proposed to grow ZnSe shells around InP core quantum dots. By monitoring the formation of ZnSe in reactions with and without InP seeds by quantitative absorbance and nuclear magnetic resonance (NMR) spectroscopy, we observe that the ZnSe formation rate is independent of the presence of InP cores. Similar to the seeded growth of CdSe and CdS, this observation supports a ZnSe growth mechanism through the inclusion of reactive ZnSe monomers that form homogeneously in the solution. Furthermore, by combining NMR and mass spectrometry, we identified the dominant reaction products of the ZnSe formation reaction as oleylammonium chloride and amino-substitutions of TOP, i.e., iminophosphoranes (TOP=NR), aminophosphonium chloride salts [TOP(NHR)Cl], and bis(amino)phosphoranes [TOP(NHR)2]. Based on the acquired results, we outline a reaction scheme that involves the complexation of TOP=Se by ZnCl2, followed by the nucleophilic addition of oleylamine onto the Lewis acid activated P-Se bond, thereby eliminating ZnSe monomers and forming amino-substitutions of TOP. Our work highlights the central role of oleylamine, acting as both the nucleophile and Brønsted base, in the transformation of metal halides and alkylphosphine chalcogenides into metal chalcogenides.
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Cloruros , Nanopartículas , Zinc , Nanopartículas/químicaRESUMEN
Background: There is still no consensus on perioperative pain control techniques in patients undergoing laparoscopic surgery; protocols of conventional therapy can be improved by the use of perioperative anaesthesiologic techniques, such as epidural or loco-regional analgesic administration as transversus abdominis plane (TAP) block. The aim of this evaluation was to investigate the role of laparoscopic-assisted TAP block during repair of diastasis recti associated with primary midline hernias in term of post-operative pain relief. Methods: This was a retrospective evaluation of a prospectively maintained database including patients undergoing laparoscopic repair of diastasis recti associated with primary ventral hernia. Patients were divided into two groups: Group A patients (n = 34) received laparoscopic-assisted bilateral TAP-block of 7.5 mg/ml ropivacaine for each side and Group B patients (n = 29) received conventional post-operative therapy. All patients received 24 h infusion of 20 mg morphine; pain was checked at 6, 24 and 48 h after surgery by numeric rating scale (NRS) score. A rescue analgesia by was given if NRS score was >4 or on patient request. Results: No differences in operative time, complications and post-operative stay, no complications related to TAP-block technique were found. Post-operative pain scores (determined by NRS) were found to be significantly different between groups. Group A patients showed a significant reduction in NRS score at 6, 24 and 48 h (P < 0.005) and in the number of patients requiring further analgesic drugs administration (P < 0.005) compared to Group B patients. Conclusions: Laparoscopic-guided TAP-block can be considered safe and effective in the management of post-operative pain and in the reduction of analgesic need in patients undergoing laparoscopic repair of diastasis recti and ventral hernias. The non-randomised nature of the study and the lack of a consistent series of patients require further evaluations.
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Plants and other organisms, but not insects or vertebrates, express the auxiliary respiratory enzyme alternative oxidase (AOX) that bypasses mitochondrial respiratory complexes III and/or IV when impaired. Persistent expression of AOX from Ciona intestinalis in mammalian models has previously been shown to be effective in alleviating some metabolic stresses produced by respiratory chain inhibition while exacerbating others. This implies that chronic AOX expression may modify or disrupt metabolic signaling processes necessary to orchestrate adaptive remodeling, suggesting that its potential therapeutic use may be confined to acute pathologies, where a single course of treatment would suffice. One possible route for administering AOX transiently is AOX-encoding nucleic acid constructs. Here we demonstrate that AOX-encoding chemically-modified RNA (cmRNA), sequence-optimized for expression in mammalian cells, was able to support AOX expression in immortalized mouse embryonic fibroblasts (iMEFs), human lung carcinoma cells (A549) and primary mouse pulmonary arterial smooth muscle cells (PASMCs). AOX protein was detectable as early as 3 h after transfection, had a half-life of ~4 days and was catalytically active, thus supporting respiration and protecting against respiratory inhibition. Our data demonstrate that AOX-encoding cmRNA optimized for use in mammalian cells represents a viable route to investigate and possibly treat mitochondrial respiratory disorders.
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Mitocondrias , ARN , Animales , Humanos , Ratones , Fibroblastos/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , ARN/metabolismo , Células A549 , TransfecciónRESUMEN
Progress in the study of circulating, cell-free nuclear DNA (ccf-nDNA) in cancer detection has led to the development of noninvasive clinical diagnostic tests and has accelerated the evaluation of ccf-nDNA abundance as a disease biomarker. Likewise, circulating, cell-free mitochondrial DNA (ccf-mtDNA) is under similar investigation. However, optimal ccf-mtDNA isolation parameters have not been established, and inconsistent protocols for ccf-nDNA collection, storage, and analysis have hindered its clinical utility. Until now, no studies have established a method for high-throughput isolation that considers both ccf-nDNA and ccf-mtDNA. We initially optimized human plasma digestion and extraction conditions for maximal recovery of these DNAs using a magnetic bead-based isolation method. However, when we incorporated this method onto a high-throughput platform, initial experiments found that DNA isolated from identical human plasma samples displayed plate edge effects resulting in low ccf-mtDNA reproducibility, whereas ccf-nDNA was less affected. Therefore, we developed a detailed protocol optimized for both ccf-mtDNA and ccf-nDNA recovery that uses a magnetic bead-based isolation process on an automated 96-well platform. Overall, we calculate an improved efficiency of recovery of â¼95-fold for ccf-mtDNA and 20-fold for ccf-nDNA when compared with the initial procedure. Digestion conditions, liquid-handling characteristics, and magnetic particle processor programming all contributed to increased recovery without detectable positional effects. To our knowledge, this is the first high-throughput approach optimized for ccf-mtDNA and ccf-nDNA recovery and serves as an important starting point for clinical studies.
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Núcleo Celular/genética , Ácidos Nucleicos Libres de Células/sangre , ADN Mitocondrial/sangre , Ensayos Analíticos de Alto Rendimiento/métodos , Mitocondrias/genética , Automatización , Ácidos Nucleicos Libres de Células/aislamiento & purificación , Ácidos Nucleicos Libres de Células/metabolismo , ADN Mitocondrial/aislamiento & purificación , ADN Mitocondrial/metabolismo , Endopeptidasa K/metabolismo , Humanos , Magnetismo , Análisis por Micromatrices , Reacción en Cadena en Tiempo Real de la Polimerasa , TemperaturaRESUMEN
Cigarette smoke (CS) exposure is the predominant risk factor for the development of chronic obstructive pulmonary disease (COPD) and the third leading cause of death worldwide. We aimed to elucidate whether mitochondrial respiratory inhibition and oxidative stress are triggers in its etiology. In different models of CS exposure, we investigated the effect on lung remodeling and cell signaling of restoring mitochondrial respiratory electron flow using alternative oxidase (AOX), which bypasses the cytochrome segment of the respiratory chain. AOX attenuated CS-induced lung tissue destruction and loss of function in mice exposed chronically to CS for 9 months. It preserved the cell viability of isolated mouse embryonic fibroblasts treated with CS condensate, limited the induction of apoptosis, and decreased the production of reactive oxygen species (ROS). In contrast, the early-phase inflammatory response induced by acute CS exposure of mouse lung, i.e., infiltration by macrophages and neutrophils and adverse signaling, was unaffected. The use of AOX allowed us to obtain novel pathomechanistic insights into CS-induced cell damage, mitochondrial ROS production, and lung remodeling. Our findings implicate mitochondrial respiratory inhibition as a key pathogenic mechanism of CS toxicity in the lung. We propose AOX as a novel tool to study CS-related lung remodeling and potentially to counteract CS-induced ROS production and cell damage.
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Fumar Cigarrillos/efectos adversos , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Nicotiana/efectos adversos , Oxidorreductasas/genética , Proteínas de Plantas/genética , Enfermedad Pulmonar Obstructiva Crónica/genética , Animales , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Mezclas Complejas/farmacología , Modelos Animales de Enfermedad , Proteínas del Complejo de Cadena de Transporte de Electrón/genética , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Embrión de Mamíferos , Femenino , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/enzimología , Expresión Génica , Pulmón/efectos de los fármacos , Pulmón/enzimología , Pulmón/fisiopatología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/patología , Ratones , Ratones Transgénicos , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Proteínas Mitocondriales/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Neutrófilos/patología , Estrés Oxidativo , Oxidorreductasas/metabolismo , Proteínas de Plantas/metabolismo , Cultivo Primario de Células , Enfermedad Pulmonar Obstructiva Crónica/inducido químicamente , Enfermedad Pulmonar Obstructiva Crónica/enzimología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Especies Reactivas de Oxígeno/agonistas , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Nicotiana/químicaRESUMEN
The organoleptic attributes of Prunus mahaleb, a fruit representing a new source of bioactive compounds, are so pronounced that it can be consider non-edible. This study was designed to evaluate the acceptance of P. mahaleb fruits after fermentation with different Saccharomyces cerevisiae and Lactobacillus plantarum protechnological strains. Four different bacterial and one yeast strains, as single or mixed starter formulation, were used to inoculate an aqueous suspension of P. mahaleb fruits. The fermented fruits and fermentation broths were subjected to physico-chemical characterization and the organoleptic properties of both samples were also assessed by a hedonic panel. The obtained results indicated that all the employed strains were able to grow and to ferment the matrix. However, the mixed starter FG69 + Li180-7 (L. plantarum/S. cerevisiae) had the best impact on sensory characteristics of P. mahaleb fruit and fermented medium. The adopted protocol allowed us to attain edible fruits and a new fermented non-dairy drink with valuable probiotic health-promoting properties. In our knowledge, this is the first study concerning the exploitation of P. mahaleb fruits. This investigation confirmed the potential of yeasts and lactic acid bacteria co-inoculation in the design of starter tailored for this kind of food applications.
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Fermentación , Frutas/microbiología , Lactobacillus plantarum/metabolismo , Prunus/microbiología , Saccharomyces cerevisiae/metabolismo , Microbiología de Alimentos , Malatos/análisis , ProbióticosRESUMEN
OBJECTIVES: Lung ultrasound is commonly used to evaluate lung morphology in patients with acute respiratory distress syndrome. Aim of this study was to determine lung ultrasound reliability in assessing lung aeration and positive end-expiratory pressure-induced recruitment compared with CT. DESIGN: Randomized crossover study. SETTING: University hospital ICU. PATIENTS: Twenty sedated paralyzed acute respiratory distress syndrome patients: age 56 years (43-72 yr), body mass index 25 kg/m (22-27 kg/m), and PaO2/FIO2 160 (113-218). INTERVENTIONS: Lung CT and lung ultrasound examination were performed at positive end-expiratory pressure 5 and 15 cm H2O. MEASUREMENTS AND MAIN RESULTS: Global and regional Lung Ultrasound scores were compared with CT quantitative analysis. Lung recruitment (i.e., decrease in not aerated tissue as assessed with CT) was compared with global Lung Ultrasound score variations. Global Lung Ultrasound score was strongly associated with average lung tissue density at positive end-expiratory pressure 5 (R = 0.78; p < 0.0001) and positive end-expiratory pressure 15 (R = 0.62; p < 0.0001). Regional Lung Ultrasound score strongly correlated with tissue density at positive end-expiratory pressure 5 (rs = 0.79; p < 0.0001) and positive end-expiratory pressure 15 (rs = 0.79; p < 0.0001). Each step increase of regional Lung Ultrasound score was associated with significant increase of tissue density (p < 0.005). A substantial agreement was found between regional Lung Ultrasound score and CT classification at positive end-expiratory pressure 5 (k = 0.69 [0.63-0.75]) and at positive end-expiratory pressure 15 (k = 0.70 [0.64-0.75]). At positive end-expiratory pressure 15, both global Lung Ultrasound score (22 [16-27] vs 26 [21-29]; p < 0.0001) and not aerated tissue (42% [25-57%] vs 52% [39-67%]; p < 0.0001) decreased. However, Lung Ultrasound score variations were not associated with lung recruitment (R = 0.01; p = 0.67). CONCLUSIONS: Lung Ultrasound score is a valid tool to assess regional and global lung aeration. Global Lung Ultrasound score variations should not be used for bedside assessment of positive end-expiratory pressure-induced recruitment.
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Alveolos Pulmonares/diagnóstico por imagen , Alveolos Pulmonares/fisiopatología , Intercambio Gaseoso Pulmonar/fisiología , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/fisiopatología , Adulto , Anciano , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/fisiopatología , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
BACKGROUND: The ventilator works mechanically on the lung parenchyma. The authors set out to obtain the proof of concept that ventilator-induced lung injury (VILI) depends on the mechanical power applied to the lung. METHODS: Mechanical power was defined as the function of transpulmonary pressure, tidal volume (TV), and respiratory rate. Three piglets were ventilated with a mechanical power known to be lethal (TV, 38 ml/kg; plateau pressure, 27 cm H2O; and respiratory rate, 15 breaths/min). Other groups (three piglets each) were ventilated with the same TV per kilogram and transpulmonary pressure but at the respiratory rates of 12, 9, 6, and 3 breaths/min. The authors identified a mechanical power threshold for VILI and did nine additional experiments at the respiratory rate of 35 breaths/min and mechanical power below (TV 11 ml/kg) and above (TV 22 ml/kg) the threshold. RESULTS: In the 15 experiments to detect the threshold for VILI, up to a mechanical power of approximately 12 J/min (respiratory rate, 9 breaths/min), the computed tomography scans showed mostly isolated densities, whereas at the mechanical power above approximately 12 J/min, all piglets developed whole-lung edema. In the nine confirmatory experiments, the five piglets ventilated above the power threshold developed VILI, but the four piglets ventilated below did not. By grouping all 24 piglets, the authors found a significant relationship between the mechanical power applied to the lung and the increase in lung weight (r = 0.41, P = 0.001) and lung elastance (r = 0.33, P < 0.01) and decrease in PaO2/FIO2 (r = 0.40, P < 0.001) at the end of the study. CONCLUSION: In piglets, VILI develops if a mechanical power threshold is exceeded.
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Lesión Pulmonar Inducida por Ventilación Mecánica/fisiopatología , Ventiladores Mecánicos , Presión del Aire , Animales , Elasticidad , Diseño de Equipo , Capacidad Inspiratoria , Pulmón/diagnóstico por imagen , Pulmón/patología , Pulmón/fisiopatología , Fenómenos Mecánicos , Tamaño de los Órganos , Edema Pulmonar/inducido químicamente , Edema Pulmonar/patología , Radiografía , Frecuencia Respiratoria , Sus scrofa , Lesión Pulmonar Inducida por Ventilación Mecánica/patologíaRESUMEN
Leber's hereditary optic neuropathy is a maternally inherited blinding disease caused as a result of homoplasmic point mutations in complex I subunit genes of mitochondrial DNA. It is characterized by incomplete penetrance, as only some mutation carriers become affected. Thus, the mitochondrial DNA mutation is necessary but not sufficient to cause optic neuropathy. Environmental triggers and genetic modifying factors have been considered to explain its variable penetrance. We measured the mitochondrial DNA copy number and mitochondrial mass indicators in blood cells from affected and carrier individuals, screening three large pedigrees and 39 independently collected smaller families with Leber's hereditary optic neuropathy, as well as muscle biopsies and cells isolated by laser capturing from post-mortem specimens of retina and optic nerves, the latter being the disease targets. We show that unaffected mutation carriers have a significantly higher mitochondrial DNA copy number and mitochondrial mass compared with their affected relatives and control individuals. Comparative studies of fibroblasts from affected, carriers and controls, under different paradigms of metabolic demand, show that carriers display the highest capacity for activating mitochondrial biogenesis. Therefore we postulate that the increased mitochondrial biogenesis in carriers may overcome some of the pathogenic effect of mitochondrial DNA mutations. Screening of a few selected genetic variants in candidate genes involved in mitochondrial biogenesis failed to reveal any significant association. Our study provides a valuable mechanism to explain variability of penetrance in Leber's hereditary optic neuropathy and clues for high throughput genetic screening to identify the nuclear modifying gene(s), opening an avenue to develop predictive genetic tests on disease risk and therapeutic strategies.
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ADN Mitocondrial/genética , Recambio Mitocondrial/genética , Atrofia Óptica Hereditaria de Leber/diagnóstico , Atrofia Óptica Hereditaria de Leber/genética , Penetrancia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , Adulto JovenRESUMEN
Amyloidosis is a rare infiltrative condition resulting from the extracellular accumulation of amyloid fibrils at the cardiac level. It can be an acquired condition or due to genetic mutations. With the progression of imaging technologies, a non-invasive diagnosis was proposed. In this study, we discuss the role of CMR in cardiac amyloidosis, focusing on the two most common subtypes (AL and ATTR), waiting for evidence-based guidelines to be published.
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Neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD), are severe age-related disorders with complex and multifactorial causes. Recent research suggests a critical link between neurodegeneration and the gut microbiome, via the gut-brain communication pathway. This review examines the role of trimethylamine N-oxide (TMAO), a gut microbiota-derived metabolite, in the development of AD and PD, and investigates its interaction with microRNAs (miRNAs) along this bidirectional pathway. TMAO, which is produced from dietary metabolites like choline and carnitine, has been linked to increased neuroinflammation, protein misfolding, and cognitive decline. In AD, elevated TMAO levels are associated with amyloid-beta and tau pathologies, blood-brain barrier disruption, and neuronal death. TMAO can cross the blood-brain barrier and promote the aggregation of amyloid and tau proteins. Similarly, TMAO affects alpha-synuclein conformation and aggregation, a hallmark of PD. TMAO also activates pro-inflammatory pathways such as NF-kB signaling, exacerbating neuroinflammation further. Moreover, TMAO modulates the expression of various miRNAs that are involved in neurodegenerative processes. Thus, the gut microbiome-miRNA-brain axis represents a newly discovered mechanistic link between gut dysbiosis and neurodegeneration. MiRNAs regulate the key pathways involved in neuroinflammation, oxidative stress, and neuronal death, contributing to disease progression. As a direct consequence, specific miRNA signatures may serve as potential biomarkers for the early detection and monitoring of AD and PD progression. This review aims to elucidate the complex interrelationships between the gut microbiota, trimethylamine-N-oxide (TMAO), microRNAs (miRNAs), and the central nervous system, and the implications of these connections in neurodegenerative diseases. In this context, an overview of the current neuroradiology techniques available for studying neuroinflammation and of the animal models used to investigate these intricate pathologies will also be provided. In summary, a bulk of evidence supports the concept that modulating the gut-brain communication pathway through dietary changes, the manipulation of the microbiome, and/or miRNA-based therapies may offer novel approaches for implementing the treatment of debilitating neurological disorders.
RESUMEN
Indium phosphide (InP) quantum dots (QDs) are considered the most promising alternative for Cd and Pb-based QDs for lighting and display applications. However, while core-only QDs of CdSe and CdTe have been prepared with near-unity photoluminescence quantum yield (PLQY), this is not yet achieved for InP QDs. Treatments with HF have been used to boost the PLQY of InP core-only QDs up to 85%. However, HF etches the QDs, causing loss of material and broadening of the optical features. Here, we present a simple postsynthesis HF-free treatment that is based on passivating the surface of the InP QDs with InF3. For optimized conditions, this results in a PLQY as high as 93% and nearly monoexponential photoluminescence decay. Etching of the particle surface is entirely avoided if the treatment is performed under stringent acid-free conditions. We show that this treatment is applicable to InP QDs with various sizes and InP QDs obtained via different synthesis routes. The optical properties of the resulting core-only InP QDs are on par with InP/ZnSe/ZnS core-shell QDs, with significantly higher absorption coefficients in the blue, and with potential for faster charge transport. These are important advantages when considering InP QDs for use in micro-LEDs or photodetectors.