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1.
J Chem Inf Model ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950140

RESUMEN

Deep eutectic solvents (DESs) have attracted increasing attention in recent years due to their broad applicability in different fields, but their computer-aided discovery, which avoids a time-consuming trial-and-error investigation, is still lagging. In this paper, a set of nine DESs, composed of choline chloride as a hydrogen-bond acceptor and nine functionalized phenols as hydrogen bond donors, is simulated by using classical molecular dynamics to investigate the possible formation of a DES. The tool of the Voronoi tessellation analysis is employed for producing an intuitive and straightforward representation of the degree of mixing between the different components of the solutions, therefore permitting the definition of a metric quantifying the propensity of the components to produce a uniform solution. The computational findings agree with the experimental results, thus confirming that the Voronoi tessellation analysis can act as a lightweight yet powerful approach for the high-throughput screening of mixtures in the optics of the new DES design.

2.
Angew Chem Int Ed Engl ; 63(10): e202318204, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38244210

RESUMEN

Aluminum-sulfur (Al-S) batteries are promising energy storage devices due to their high theoretical capacity, low cost, and high safety. However, the high viscosity and inferior ion transport of conventionally used ionic liquid electrolytes (ILEs) limit the kinetics of Al-S batteries, especially at sub-zero temperatures. Herein, locally concentrated ionic liquid electrolytes (LCILE) formed via diluting the ILEs with non-solvating 1,2-difluorobenzene (dFBn) co-solvent are proposed for wide-temperature-range Al-S batteries. The addition of dFBn effectively promotes the fluidity and ionic conductivity without affecting the AlCl4 - /Al2 Cl7 - equilibrium, which preserves the reversible stripping/plating of aluminum and further promotes the overall kinetics of Al-S batteries. As a result, Al-S cells employing the LCILE exhibit higher specific capacity, better cyclability, and lower polarization with respect to the neat ILE in a wide temperature range from -20 to 40 °C. For instance, Al-S batteries employing the LCILE sustain a remarkable capacity of 507 mAh g-1 after 300 cycles at 20 °C, while only 229 mAh g-1 is delivered with the dFBn-free electrolyte under the same condition. This work demonstrates the favorable use of LCILEs for wide-temperature Al-S batteries.

3.
Eur Respir J ; 61(2)2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36229045

RESUMEN

Pleural infection is a common condition encountered by respiratory physicians and thoracic surgeons alike. The European Respiratory Society (ERS) and European Society of Thoracic Surgeons (ESTS) established a multidisciplinary collaboration of clinicians with expertise in managing pleural infection with the aim of producing a comprehensive review of the scientific literature. Six areas of interest were identified: 1) epidemiology of pleural infection, 2) optimal antibiotic strategy, 3) diagnostic parameters for chest tube drainage, 4) status of intrapleural therapies, 5) role of surgery and 6) current place of outcome prediction in management. The literature revealed that recently updated epidemiological data continue to show an overall upwards trend in incidence, but there is an urgent need for a more comprehensive characterisation of the burden of pleural infection in specific populations such as immunocompromised hosts. There is a sparsity of regular analyses and documentation of microbiological patterns at a local level to inform geographical variation, and ongoing research efforts are needed to improve antibiotic stewardship. The evidence remains in favour of a small-bore chest tube optimally placed under image guidance as an appropriate initial intervention for most cases of pleural infection. With a growing body of data suggesting delays to treatment are key contributors to poor outcomes, this suggests that earlier consideration of combination intrapleural enzyme therapy (IET) with concurrent surgical consultation should remain a priority. Since publication of the MIST-2 study, there has been considerable data supporting safety and efficacy of IET, but further studies are needed to optimise dosing using individualised biomarkers of treatment failure. Pending further prospective evaluation, the MIST-2 regimen remains the most evidence based. Several studies have externally validated the RAPID score, but it requires incorporating into prospective intervention studies prior to adopting into clinical practice.


Asunto(s)
Enfermedades Transmisibles , Enfermedades Pleurales , Cirujanos , Adulto , Humanos , Etiquetas de Secuencia Expresada , Tubos Torácicos
4.
Mycopathologia ; 188(5): 683-691, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36239834

RESUMEN

OBJECTIVES: Chronic pulmonary aspergillosis (CPA) is a research priority in fungal diseases with a need for new studies to reduce misdiagnosis with more common diseases, discuss improvement in diagnostic methods and better characterize gaps in antifungal and surgical treatments to improve clinical outcomes. METHODS: In this retrospective study, we reviewed medical records of patients diagnosed with CPA from January 2010 to June 2021 at University of São Paulo, São Paulo, Brazil. We evaluated clinical characteristics, radiological findings, serology, treatment, and outcomes. RESULTS: The study included 91 participants, with 43 (47.3%) patients who underwent surgery and 69 (75.8%) received antifungal therapy. We found a predominance of middle-aged adults (median 51 years), males (n = 58, 64%) with lower BMI (median 21.3 kg/m2). The most common underlying lung disease was pulmonary tuberculosis (n = 70, 76.9%). The commonest symptoms were cough (n = 67, 74%), haemoptysis, and dyspnea (n = 63, 70%). The most common chest computerized tomography abnormalities were cavity (n = 86, 94.5%), with a predominance of mycetomas (n = 78, 91%). The serology was positive in 81% (61/75). The one-year mortality was low (3.3%). Clinical improvement and stability occurred in 89% of participants for constitucional symptoms and 86% for pulmonary symptoms. While serological improvement and stability occurred in 71%. Radiological improvement and stability occurred in 75%. CONCLUSION: We observed a good outcome after 1-year follow-up, in which the majority had improvement or stability of pulmonary and constitutional symptoms, decrease in CIE titers and low mortality.


Asunto(s)
Antifúngicos , Aspergilosis Pulmonar , Adulto , Masculino , Persona de Mediana Edad , Humanos , Antifúngicos/uso terapéutico , Estudios Retrospectivos , Brasil/epidemiología , Aspergilosis Pulmonar/diagnóstico , Aspergilosis Pulmonar/tratamiento farmacológico , Aspergilosis Pulmonar/epidemiología , Pulmón , Enfermedad Crónica
5.
Int J Mol Sci ; 24(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36835652

RESUMEN

DiGeorge syndrome (DGS) is a rare genetic disease caused by microdeletions of the 22q11.2 region (DGS1). A haploinsufficiency at 10p level has been proposed also as a DGS cause (DGS2). Clinical manifestations are variable. The most frequent features are thymic hypoplasia or aplasia with consequent immune deficiency, cardiac malformations, hypoparathyroidism, facial and palatine abnormalities, variable degrees of cognitive impairment and psychiatric disorders. The specific aim of this descriptive report is to discuss the correlation between oxidative stress and neuroinflammation in DGS patients with microdeletions of the 22q11.2 region. The deleted chromosomic region maps various genes involved in mitochondrial metabolisms, such as DGCR8 and TXNRD2, that could lead to reactive oxygen species (ROS) increased production and antioxidant depletion. Furthermore, increased levels of ROS in mitochondria would lead to the destruction of the projection neurons in the cerebral cortex with consequent neurocognitive impairment. Finally, the increase in modified protein belonging to the family of sulfoxide compounds and hexoses, acting as inhibitors of the IV and V mitochondria complex, could result in direct ROS overproduction. Neuroinflammation in DGS individuals could be directly related to the development of the syndrome's characteristic psychiatric and cognitive disorders. In patients with psychotic disorders, the most frequent psychiatric manifestation in DGS, Th-17, Th-1 and Th-2 cells are increased with consequent elevation of proinflammatory cytokine IL-6 and IL1ß. In patients with anxiety disorders, both CD3 and CD4 are increased. Some patients with autism spectrum disorders (ASDs) have an augmented level of proinflammatory cytokines IL-12, IL-6 and IL-1ß, while IFNγ and the anti-inflammatory cytokine IL-10 seem to be reduced. Other data proposed that altered synaptic plasticity could be directly involved in DGS cognitive disorders. In conclusion, the use of antioxidants for restoring mitochondrial functionality in DGS could be a useful tool to protect cortical connectivity and cognitive behavior.


Asunto(s)
Síndrome de DiGeorge , MicroARNs , Humanos , Síndrome de DiGeorge/genética , Especies Reactivas de Oxígeno , Enfermedades Neuroinflamatorias , Interleucina-6 , Proteínas de Unión al ARN , Estrés Oxidativo
6.
Angew Chem Int Ed Engl ; 62(17): e202219318, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-36727727

RESUMEN

Non-flammable ionic liquid electrolytes (ILEs) are well-known candidates for safer and long-lifespan lithium metal batteries (LMBs). However, the high viscosity and insufficient Li+ transport limit their practical application. Recently, non-solvating and low-viscosity co-solvents diluting ILEs without affecting the local Li+ solvation structure are employed to solve these problems. The diluted electrolytes, i.e., locally concentrated ionic liquid electrolytes (LCILEs), exhibiting lower viscosity, faster Li+ transport, and enhanced compatibility toward lithium metal anodes, are feasible options for the next-generation high-energy-density LMBs. Herein, the progress of the recently developed LCILEs are summarised, including their physicochemical properties, solution structures, and applications in LMBs with a variety of high-energy cathode materials. Lastly, a perspective on the future research directions of LCILEs to further understanding and achieve improved cell performances is outlined.

7.
Angew Chem Int Ed Engl ; 62(31): e202305840, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37249166

RESUMEN

Lithium metal is a promising anode material for next-generation high-energy-density batteries but suffers from low stripping/plating Coulombic efficiency and dendritic growth particularly at sub-zero temperatures. Herein, a poorly-flammable, locally concentrated ionic liquid electrolyte with a wide liquidus range extending well below 0 °C is proposed for low-temperature lithium metal batteries. Its all-anion Li+ solvation and phase-nano-segregation solution structure are sustained at low temperatures, which, together with a solid electrolyte interphase rich in inorganic compounds, enable dendrite-free operation of lithium metal anodes at -20 °C and 0.5 mA cm-2 , with a Coulombic efficiency of 98.9 %. As a result, lithium metal batteries coupling thin lithium metal anodes (4 mAh cm-2 ) and high-loading LiNi0.8 Co0.15 Al0.05 O2 cathodes (10 mg cm-2 ) retain 70 % of the initial capacity after 100 cycles at -20 °C. These results, as a proof of concept, demonstrate the applicability of locally concentrated ionic liquid electrolytes for low-temperature lithium metal batteries.

8.
Small ; 18(31): e2201563, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35810459

RESUMEN

Halide-free, water-in-salt electrolytes (WiSEs) composed of potassium acetate (KAc) and zinc acetate (ZnAc2 ) are investigated as electrolytes in zinc-ion hybrid supercapacitors (ZHSs). Molecular dynamics simulations demonstrate that water molecules are mostly non-interacting with each other in the highly concentrated WiSEs, while "bulk-like water" regions are present in the dilute electrolyte. Among the various concentrated electrolytes investigated, the 30 m KAc and 1 m ZnAc2 electrolyte (30K1Zn) grants the best performance in terms of reversibility and stability of Zn plating/stripping while the less concentrated electrolyte cannot suppress corrosion of Zn and hydrogen evolution. The ZHSs utilizing 30K1Zn, in combination with a commercial activated carbon (AC) positive electrode and Zn as the negative electrode, deliver a capacity of 65 mAh g-1 (based on the AC weight) at a current density of 5 A g-1 . They also offer an excellent capacity retention over 10 000 cycles and an impressive coulombic efficiency (≈100%).

9.
Phys Chem Chem Phys ; 23(36): 20282-20287, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34486605

RESUMEN

Herein we report the first in-depth structural characterisation of simple linear carboxylic acids with alkyl tail length ranging from one to six carbon atoms. By means of the SWAXS technique, a pronounced nanoscopic heterogeneity evolving along the aliphatic portion of the molecule is highlighted. Via classical molecular dynamics, the origin of such heterogeneity is unambiguously assigned to the existence of aliphatic domains resulting from the self-segregation of the polar and apolar portions of the molecules. Furthermore, the structural correlation of aliphatic-separated polar domains is responsible for observing the so-called "pre-peak" in the SAXS region.

10.
Soft Matter ; 16(33): 7751-7759, 2020 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-32744265

RESUMEN

The packing of proteins and their collective behavior in crowded media is crucial for the understanding of biological processes. Here we study the structural and dynamical evolution of solutions of the globular protein bovine serum albumin with increasing concentration via drying using small angle X-ray scattering and dynamic light scattering. We probe an evolving correlation peak on the scattering profile, corresponding to the inter-protein distance, ξ, which decreases following a power law of the protein volume fraction, φ. The rate of decrease in ξ becomes faster above a protein concentration of ∼200 mg ml-1 (φ = 0.15). The power law exponent changes from 0.33, which is typical of colloidal or protein solutions, to 0.41. During the entire drying process, we observe the development and the growth of two-step relaxation dynamics with increasing φ as revealed by dynamic light scattering. We find three different regimes of the dependence of ξ as a function of φ. In the dilute regime (φ < 0.22), protein molecules are far apart from each other compared to their size. In this case, the dynamics mainly corresponds to Brownian motion. At an intermediate concentration (0.22 < φ < 0.47), inter-protein distances become comparable to the size of protein molecules, leading to a preferential orientation of the ellipsoidal protein molecules along with a possible deformation. In this regime, the dynamics shows two distinct relaxation times. At a very high concentration (φ > 0.47), the system reaches a jammed state. Subsequently, the secondary relaxation time in this state becomes extremely slow. In this state, the protein molecules have approximately one hydration layer. This study contributes to the understanding of protein molecular packing in crowded environments and the phenomenon of density-driven jamming for soft matter systems.


Asunto(s)
Proteínas
11.
J Neuroinflammation ; 16(1): 9, 2019 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-30651101

RESUMEN

BACKGROUND: Phagocytosis is a key function of myeloid cells and is highly involved in brain ischemic injury. It has been scarcely studied in vivo, thus preventing a deep knowledge of the processes occurring in the ischemic environment. Structured illumination microscopy (SIM) is a superresolution technique which helps study phagocytosis, a process involving the recruitment of vesicles sized below the resolution limits of standard confocal microscopy. METHODS: Mice underwent permanent occlusion of the middle cerebral artery and were sacrificed at 48 h or 7 days after insult. Immunofluorescence for CD11b, myeloid cell membrane marker, and CD68, lysosomal marker was done in the ischemic area. Images were acquired using a SIM system and verified with SIM check. Lysosomal distribution was measured in the ischemic area by the gray level co-occurrence matrix (GLCM). SIM dataset was compared with transmission electron microscopy images of macrophages in the ischemic tissue at the same time points. Cultured microglia were stimulated with LPS to uptake 100 nm fluorescent beads and imaged by time-lapse SIM. GLCM was used to analyze bead distribution over the cytoplasm. RESULTS: SIM images reached a resolution of 130 nm and passed the quality control diagnose, ruling out possible artifacts. After ischemia, GLCM applied to the CD68 images showed that myeloid cells at 48 h had higher angular second moment (ASM), inverse difference moment (IDM), and lower entropy than myeloid cells at 7 days indicating higher lysosomal clustering at 48 h. At this time point, lysosomal clustering was proximal (< 700 nm) to the cell membrane indicating active target internalization, while at 7 days, it was perinuclear, consistent with final stages of phagocytosis or autophagy. Electron microscopy images indicated a similar pattern of lysosomal distribution thus validating the SIM dataset. GLCM on time-lapse SIM from phagocytic microglia cultures revealed a temporal decrease in ASM and IDM and increase in entropy, as beads were uptaken, indicating that GLCM informs on the progression of phagocytosis. CONCLUSIONS: GLCM analysis on SIM dataset quantitatively described different phases of macrophage phagocytic behavior revealing the dynamics of lysosomal movements in the ischemic brain indicating initial active internalization vs. final digestion/autophagy.


Asunto(s)
Encéfalo/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/patología , Células Mieloides/fisiología , Imagen Óptica/métodos , Fagocitosis/fisiología , Animales , Animales Recién Nacidos , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Antígeno CD11b/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Lipopolisacáridos/farmacología , Lisosomas/patología , Lisosomas/ultraestructura , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Microglía/ultraestructura , Microscopía Electrónica de Transmisión , Células Mieloides/ultraestructura , Médula Espinal/citología , Factores de Tiempo
12.
J Neuroinflammation ; 15(1): 65, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29495962

RESUMEN

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects the motor neuromuscular system leading to complete paralysis and premature death. The multifactorial nature of ALS that involves both cell-autonomous and non-cell-autonomous processes contributes to the lack of effective therapies, usually targeted to a single pathogenic mechanism. RNS60, an experimental drug containing oxygenated nanobubbles generated by modified Taylor-Couette-Poiseuille flow with elevated oxygen pressure, has shown anti-inflammatory and neuroprotective properties in different experimental paradigms. Since RNS60 interferes with multiple cellular mechanisms known to be involved in ALS pathology, we evaluated its effect in in vitro and in vivo models of ALS. METHODS: Co-cultures of primary microglia/spinal neurons exposed to LPS and astrocytes/spinal neurons from SOD1G93A mice were used to examine the effect of RNS60 or normal saline (NS) on the selective motor neuron degeneration. Transgenic SOD1G93A mice were treated with RNS60 or NS (300 µl/mouse intraperitoneally every other day) starting at the disease onset and examined for disease progression as well as pathological and biochemical alterations. RESULTS: RNS60 protected motor neurons in in vitro paradigms and slowed the disease progression of C57BL/6-SOD1G93A mice through a significant protection of spinal motor neurons and neuromuscular junctions. This was mediated by the (i) activation of an antioxidant response and generation of an anti-inflammatory environment in the spinal cord; (ii) activation of the PI3K-Akt pro-survival pathway in the spinal cord and sciatic nerves; (iii) reduced demyelination of the sciatic nerves; and (iv) elevation of peripheral CD4+/Foxp3+ T regulatory cell numbers. RNS60 did not show the same effects in 129Sv-SOD1G93A mice, which are unable to activate a protective immune response. CONCLUSION: RNS60 demonstrated significant therapeutic efficacy in C57BL/6-SOD1G93A mice by virtue of its effects on multiple disease mechanisms in motor neurons, glial cells, and peripheral immune cells. These findings, together with the excellent clinical safety profile, make RNS60 a promising candidate for ALS therapy and support further studies to unravel its molecular mechanism of action. In addition, the differences in efficacy of RNS60 in SOD1G93A mice of different strains may be relevant for identifying potential markers to predict efficacy in clinical trials.


Asunto(s)
Esclerosis Amiotrófica Lateral/complicaciones , Esclerosis Amiotrófica Lateral/patología , Antiinflamatorios no Esteroideos/uso terapéutico , Neuroglía/efectos de los fármacos , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/genética , Animales , Proteínas de Unión al Calcio/metabolismo , Células Cultivadas , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Embrión de Mamíferos , Proteína Ácida Fibrilar de la Glía/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas de Microfilamentos/metabolismo , Trastornos Motores/tratamiento farmacológico , Trastornos Motores/etiología , Neuronas Motoras/efectos de los fármacos , Unión Neuromuscular/efectos de los fármacos , Unión Neuromuscular/patología , Proyección Neuronal/efectos de los fármacos , Enfermedades del Sistema Nervioso Periférico/etiología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Cloruro de Sodio/uso terapéutico , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo
13.
Respir Res ; 19(1): 83, 2018 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-29739412

RESUMEN

BACKGROUND: Lymphangioleiomyomatosis (LAM) is a low-grade neoplasm characterized by the pulmonary infiltration of smooth muscle-like cells (LAM cells) and cystic destruction. Patients usually present with airway obstruction in pulmonary function tests (PFTs). Previous studies have shown correlations among histological parameters, lung function abnormalities and prognosis in LAM. We investigated the lung tissue expression of proteins related to the mTOR pathway, angiogenesis and enzymatic activity and its correlation with functional parameters in LAM patients. METHODS: We analyzed morphological and functional parameters of thirty-three patients. Two groups of disease severity were identified according to FEV1 values. Lung tissue from open biopsies or lung transplants was immunostained for SMA, HMB-45, mTOR, VEGF-D, MMP-9 and D2-40. Density of cysts, density of nodules and protein expression were measured by image analysis and correlated with PFT parameters. RESULTS: There was no difference in the expression of D2-40 between the more severe and the less severe groups. All other immunohistological parameters showed significantly higher values in the more severe group (p ≤ 0.002). The expression of VEGF-D, MMP-9 and mTOR in LAM cells was associated with the density of both cysts and nodules. The density of cysts and nodules as well as the expression of MMP-9 and VEGF-D were associated with the impairment of PFT parameters. CONCLUSIONS: Severe LAM represents an active phase of the disease with high expression of VEGF-D, mTOR, and MMP-9, as well as LAM cell infiltration. Our findings suggest that the tissue expression levels of VEGF-D and MMP-9 are important parameters associated with the loss of pulmonary function and could be considered as potential severity markers in open lung biopsies of LAM patients.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Neoplasias Pulmonares/metabolismo , Linfangioleiomiomatosis/metabolismo , Metaloproteinasa 9 de la Matriz/biosíntesis , Serina-Treonina Quinasas TOR/biosíntesis , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Adulto , Femenino , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/patología , Linfangioleiomiomatosis/patología , Metaloproteinasa 9 de la Matriz/análisis , Persona de Mediana Edad , Estudios Retrospectivos , Serina-Treonina Quinasas TOR/análisis , Factor A de Crecimiento Endotelial Vascular/análisis
14.
Phys Chem Chem Phys ; 20(42): 27214-27225, 2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30351336

RESUMEN

In the presence of trivalent cations, negatively charged globular proteins show a rich phase behaviour including reentrant condensation, crystallisation, clustering and lower critical solution temperature metastable liquid-liquid phase separation (LCST-LLPS). Here, we present a systematic study on how different multivalent cations can be employed to tune the interactions and the associated phase behaviour of proteins. We focus our investigations on the protein bovine serum albumin (BSA) in the presence of HoCl3, LaCl3 and YCl3. Using UV-Vis spectroscopy and small-angle X-ray scattering (SAXS), we find that the interprotein attraction induced by Ho3+ is very strong, while the one induced by La3+ is comparatively weak when comparing the data to BSA-Y3+ systems based on our previous work. Using zeta potential and isothermal titration calorimetry (ITC) measurements, we establish different binding affinities of cations to BSA with Ho3+ having the highest one. We propose that a combination of different cation features such as radius, polarisability and in particular hydration effects determine the protein-protein interaction induced by these cations. Our findings imply that subtle differences in cation properties can be a sensitive tool to fine-tune protein-protein interactions and phase behaviour in solution.


Asunto(s)
Cationes/química , Metales Pesados/química , Albúmina Sérica Bovina/química , Soluciones/química , Animales , Calorimetría/métodos , Bovinos , Holmio/química , Lantano/química , Transición de Fase , Termodinámica , Temperatura de Transición , Agua/química , Itrio/química
15.
J Chem Phys ; 148(13): 134507, 2018 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-29626911

RESUMEN

In this article, we report the study of structural and dynamical properties for a series of acetonitrile/propylammonium nitrate mixtures as a function of their composition. These systems display an unusual increase in intensity in their X-ray diffraction patterns in the low-q regime, and their 1H-NMR diffusion-ordered NMR spectroscopy (DOSY) spectra display unusual diffusivities. However, the magnitude of both phenomena for mixtures of propylammonium nitrate is smaller than those observed for ethylammonium nitrate mixtures with the same cosolvent, suggesting that the cation alkyl tail plays an important role in these observations. The experimental X-ray scattering data are compared with the results of molecular dynamics simulations, including both ab initio studies used to interpret short-range interactions and classical simulations to describe longer range interactions. The higher level calculations highlight the presence of a strong hydrogen bond network within the ionic liquid, only slightly perturbed even at high acetonitrile concentration. These strong interactions lead to the symmetry breaking of the NO3- vibrations, with a splitting of about 88 cm-1 in the ν3 antisymmetric stretch. The classical force field simulations use a greater number of ion pairs, but are not capable of fully describing the longest range interactions, although they do successfully account for the observed concentration trend, and the analysis of the models confirms the nano-inhomogeneity of these kinds of samples.

16.
Phys Chem Chem Phys ; 19(40): 27212-27220, 2017 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-28975937

RESUMEN

Binary mixtures of ethylammonium nitrate and acetonitrile show interesting properties that originate from the structural and dynamical nano-heterogeneity present in ionic liquids. These effects are most pronounced when the ionic liquid is the minority compound. In this study the transport properties of such mixtures are studied, including viscosity, self-diffusion and conductivity. The results strongly support the presence of structural inhomogeneity and show an interesting composition-dependent behaviour in the mixtures.

17.
Chemphyschem ; 17(19): 3023-3029, 2016 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-27350160

RESUMEN

We present an exhaustive computational study on the effect of high pressure on normal alcohols with alkyl chains with lengths of three-to-eight carbon atoms. 1-Propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, and 1-octanol were studied by using classical molecular dynamics simulations and applying pressures in the range of 1 to 104  bar. The results of our calculations show that high-pressure values affect the structure significantly. In particular, we have observed a marked difference in behavior for alcohols with chain lengths below six and those with more than six or seven carbon atoms, with hexanol and heptanol being boundary cases. We have named the model with the most shrunk alkyl chains as the Asclepius form inspired by the Rod of Asclepius, the universally known symbol of medicine, in which a snake is coiled around a rod.

18.
Pharmacol Res ; 103: 180-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26640075

RESUMEN

Increasing evidence indicates that inflammatory responses could play a critical role in the pathogenesis of motor neuron injury in amyotrophic lateral sclerosis (ALS). Recent findings have underlined the role of Toll-like receptors (TLRs) and the involvement of both the innate and adaptive immune responses in ALS pathogenesis. In particular, abnormal TLR4 signaling in pro-inflammatory microglia cells has been related to motoneuron degeneration leading to ALS. In this study the effect of small molecule TLR4 antagonists on in vitro ALS models has been investigated. Two different types of synthetic glycolipids and the phenol fraction extracted from commercial extra-virgin olive oil (EVOO) were selected since they efficiently inhibit TLR4 stimulus in HEK cells by interacting with the TLR4·MD-2 complex and CD14 co-receptor. Here, TLR4 antagonists efficiently protected motoneurons from LPS-induced lethality in spinal cord cultures, and inhibited the interleukine-1ß production by LPS-stimulated microglia. In motoneurons/glia cocultures obtained from wild type or SOD1 G93A mice, motoneuron death induced by SOD1mut glia was counteracted by TLR4 antagonists. The release of nitric oxide by LPS treatment or SOD1mut glia was also inhibited by EVOO, suggesting that the action of this natural extract could be mainly related to the modulation of this inflammatory mediator.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Neuronas Motoras/efectos de los fármacos , Aceite de Oliva/farmacología , Fenoles/farmacología , Receptor Toll-Like 4/antagonistas & inhibidores , Animales , Muerte Celular/efectos de los fármacos , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Células HEK293 , Humanos , Lipopolisacáridos/farmacología , Ratones Endogámicos C57BL , Ratones Transgénicos , Microglía/metabolismo , Neuronas Motoras/metabolismo , Óxido Nítrico/metabolismo , Médula Espinal/metabolismo , Superóxido Dismutasa/genética , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
19.
Lung ; 194(4): 681-6, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27300446

RESUMEN

PURPOSE: Systemic and local inflammations have been described as relevant prognostic factors in patients with cancer. However, parameters that stand for immune activity in the pleural space have not been tested as predictors of survival in patients with malignant pleural effusion. The objective of this study was to evaluate pleural lymphocytes and Adenosine Deaminase (ADA) as predictors of survival in patients with recurrent malignant pleural effusion. METHODS: Retrospective cohort study includes patients who underwent pleurodesis for malignant pleural effusion in a tertiary center. Pleural fluid protein concentration, lactate dehydrogenase, glucose, oncotic cytology, cell count, and ADA were collected before pleurodesis and analyzed. Survival analysis was performed considering pleurodesis as time origin, and death as the event. Backwards stepwise Cox regression was used to find predictors of survival. RESULTS: 156 patients (out of 196 potentially eligible) were included in this study. Most were female (72 %) and breast cancer was the most common underlying malignancy (53 %). Pleural fluid ADA level was stratified as low (<15 U/L), normal (15 ≤ ADA < 40), and high (≥40). Low and high ADA levels were associated with worse survival when compared to normal ADA (logrank: 0.0024). In multivariable analysis, abnormal ADA (<15 or ADA ≥ 40) and underlying malignancies different from lymphoma, lung, or breast cancer were associated with worse survival. Pleural fluid cell count and lymphocytes number and percentage did not correlate with survival. CONCLUSIONS: Pleural fluid Adenosine Deaminase levels (<15 or ≥40 U/L) and neoplasms other than lung, breast, or lymphoma are independent predictors of worse survival in patients with malignant pleural effusion who undergo pleurodesis.


Asunto(s)
Adenosina Desaminasa/metabolismo , Derrame Pleural Maligno/enzimología , Derrame Pleural Maligno/etiología , Anciano , Femenino , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Derrame Pleural Maligno/patología , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tasa de Supervivencia
20.
Adv Mater ; 36(1): e2309062, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37956687

RESUMEN

Lithium metal batteries (LMBs) with nickel-rich cathodes are promising candidates for next-generation high-energy-density batteries, but the lack of sufficiently protective electrode/electrolyte interphases (EEIs) limits their cyclability. Herein, trifluoromethoxybenzene is proposed as a cosolvent for locally concentrated ionic liquid electrolytes (LCILEs) to reinforce the EEIs. With a comparative study of a neat ionic liquid electrolyte (ILE) and three LCILEs employing fluorobenzene, trifluoromethylbenzene, or trifluoromethoxybenzene as cosolvents, it is revealed that the fluorinated groups tethered to the benzene ring of the cosolvents not only affect the electrolytes' ionic conductivity and fluidity, but also the EEIs' composition via adjusting the contribution of the 1-ethyl-3-methylimidazolium cation (Emim+ ) and bis(fluorosulfonyl)imide anion. Trifluoromethoxybenzene, as the optimal cosolvent, leads to a stable cycling of LMBs employing 5 mAh cm-2 lithium metal anodes (LMAs), 21 mg cm-2 LiNi0.8 Co0.15 Al0.05 (NCA) cathodes, and 4.2 µL mAh-1 electrolytes for 150 cycles with a remarkable capacity retention of 71%, thanks to a solid electrolyte interphase rich in inorganic species on LMAs and, particularly, a uniform cathode/electrolyte interphase rich in Emim+ -derived species on NCA cathodes. By contrast, the capacity retention under the same condition is only 16%, 46%, and 18% for the neat ILE and the LCILEs based on fluorobenzene and benzotrifluoride, respectively.

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