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1.
Eur Radiol ; 31(3): 1460-1470, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32909055

RESUMEN

OBJECTIVE: To identify CT-acquisition parameters accounting for radiomics variability and to develop a post-acquisition CT-image correction method to reduce variability and improve radiomics classification in both phantom and clinical applications. METHODS: CT-acquisition protocols were prospectively tested in a phantom. The multi-centric retrospective clinical study included CT scans of patients with colorectal/renal cancer liver metastases. Ninety-three radiomics features of first order and texture were extracted. Intraclass correlation coefficients (ICCs) between CT-acquisition protocols were evaluated to define sources of variability. Voxel size, ComBat, and singular value decomposition (SVD) compensation methods were explored for reducing the radiomics variability. The number of robust features was compared before and after correction using two-proportion z test. The radiomics classification accuracy (K-means purity) was assessed before and after ComBat- and SVD-based correction. RESULTS: Fifty-three acquisition protocols in 13 tissue densities were analyzed. Ninety-seven liver metastases from 43 patients with CT from two vendors were included. Pixel size, reconstruction slice spacing, convolution kernel, and acquisition slice thickness are relevant sources of radiomics variability with a percentage of robust features lower than 80%. Resampling to isometric voxels increased the number of robust features when images were acquired with different pixel sizes (p < 0.05). SVD-based for thickness correction and ComBat correction for thickness and combined thickness-kernel increased the number of reproducible features (p < 0.05). ComBat showed the highest improvement of radiomics-based classification in both the phantom and clinical applications (K-means purity 65.98 vs 73.20). CONCLUSION: CT-image post-acquisition processing and radiomics normalization by means of batch effect correction allow for standardization of large-scale data analysis and improve the classification accuracy. KEY POINTS: • The voxel size (accounting for the pixel size and slice spacing), slice thickness, and convolution kernel are relevant sources of CT-radiomics variability. • Voxel size resampling increased the mean percentage of robust CT-radiomics features from 59.50 to 89.25% when comparing CT scans acquired with different pixel sizes and from 71.62 to 82.58% when the scans were acquired with different slice spacings. • ComBat batch effect correction reduced the CT-radiomics variability secondary to the slice thickness and convolution kernel, improving the capacity of CT-radiomics to differentiate tissues (in the phantom application) and the primary tumor type from liver metastases (in the clinical application).


Asunto(s)
Análisis de Datos , Procesamiento de Imagen Asistido por Computador , Humanos , Fantasmas de Imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
2.
Am J Physiol Heart Circ Physiol ; 319(2): H481-H487, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32678706

RESUMEN

Modifiable cardiometabolic risk factors induce the release of proinflammatory cytokines and reactive oxygen species from circulating peripheral blood mononuclear cells (PBMCs), resulting in increased cardiovascular disease risk and compromised immune health. These changes may be driven by metabolic reprogramming of PBMCs, resulting in reduced mitochondrial respiration; however, this has not been fully tested. We aimed to determine the independent associations between cardiometabolic risk factors including BMI, blood pressure, fasting glucose, and plasma lipids with mitochondrial respiration in PBMCs isolated from generally healthy individuals (n = 21) across the adult lifespan (12 men/9 women; age, 56 ± 21 yr; age range, 22-78 yr; body mass index, 27.9 ± 5.7 kg/m2; blood pressure, 123 ± 16/72 ± 10 mmHg; glucose, 90 ± 14 mg/dL; low-density lipoprotein cholesterol (LDL-C), 111 ± 22 mg/dL; and high-density lipoprotein cholesterol (HDL-C), 62 ± 16 mg/dL). PBMCs were isolated from whole blood by density-dependent centrifugation and used to assess mitochondrial function by respirometry. Primary outcomes included basal and maximal oxygen consumption rate (OCR), which were subsequently used to determine spare respiratory capacity and OCR metabolic potential. After we corrected for systolic blood pressure (SBP), diastolic blood pressure (DBP), and blood glucose, LDL-C was negatively associated with maximal respiration (r = -0.56, P = 0.016), spare respiratory capacity (r = -0.58, P = 0.012), and OCR metabolic potential (r = -0.71, P = 0.0011). In addition, SBP was negatively associated with OCR metabolic potential (r = -0.62, P = 0.0056) after we corrected for DBP, blood glucose, and LDL-C. These data suggest a link between blood cholesterol, SBP, and mitochondrial health that may provide insight into how cardiometabolic risk factors contribute to impaired immune cell function.NEW & NOTEWORTHY Independent of other cardiometabolic risk factors, low-density lipoprotein cholesterol, and systolic blood pressure were found to be negatively associated with several parameters of mitochondrial respiration in peripheral blood mononuclear cells of healthy adults. These data suggest that low-density lipoprotein cholesterol and systolic blood pressure may induce metabolic reprogramming of immune cells, contributing to increased cardiovascular disease risk and impaired immune health.


Asunto(s)
Presión Sanguínea , Respiración de la Célula , LDL-Colesterol/sangre , Leucocitos Mononucleares/metabolismo , Síndrome Metabólico/metabolismo , Mitocondrias/metabolismo , Adulto , Anciano , Biomarcadores/sangre , Glucemia/análisis , Índice de Masa Corporal , Ayuno/sangre , Femenino , Humanos , Leucocitos Mononucleares/inmunología , Masculino , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/inmunología , Síndrome Metabólico/fisiopatología , Persona de Mediana Edad , Mitocondrias/inmunología , Consumo de Oxígeno , Factores de Riesgo , Adulto Joven
3.
J Biol Phys ; 41(1): 99-112, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25465849

RESUMEN

This research studies the crystalline compounds present in nopal (Opuntia ficus-indica) cladodes. The identification of the crystalline structures was performed using X-ray diffraction, scanning electron microscopy, mass spectrometry, and Fourier transform infrared spectroscopy. The crystalline structures identified were calcium carbonate (calcite) [CaCO3], calcium-magnesium bicarbonate [CaMg(CO3)2], magnesium oxide [MgO], calcium oxalate monohydrate [Ca(C2O4)•(H2O)], potassium peroxydiphosphate [K4P2O8] and potassium chloride [KCl]. The SEM images indicate that calcite crystals grow to dipyramidal, octahedral-like, prismatic, and flower-like structures; meanwhile, calcium-magnesium bicarbonate structures show rhombohedral exfoliation and calcium oxalate monohydrate is present in a drusenoid morphology. These calcium carbonate compounds have a great importance for humans because their bioavailability. This is the first report about the identification and structural analysis of calcium carbonate and calcium-magnesium bicarbonate in nopal cladodes, as well as the presence of magnesium oxide, potassium peroxydiphosphate and potassium chloride in these plants. The significance of the study of the inorganic components of these cactus plants is related with the increasing interest in the potential use of Opuntia as a raw material of products for the food, pharmaceutical, and cosmetic industries.


Asunto(s)
Opuntia/química , Carbonato de Calcio/química , Oxalato de Calcio/química , Cristalografía por Rayos X , Magnesio/química , Óxido de Magnesio/química , Opuntia/crecimiento & desarrollo , Peróxidos/química , Ácidos Fosfóricos/química , Cloruro de Potasio/química
4.
Sci Rep ; 14(1): 8075, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38580685

RESUMEN

During the preparation of fixed prosthesis (including individual bridges and crowns) it is important to select the materials that have the best features and properties to predict a successful clinical treatment. The objective of this study was to determine if the chemical and structural characteristics could cause to increase the fracture resistance, we used four bis-acryl resins Luxatemp, Protemp, Structur and Telio. Three-points bending by Flexural test were performed in ten bars and they were carried out to compare with Anova test. In addition, the bis-acryl resins were analyzed by scanning electron microscopy, to analyze microstructure and morphology and the molecular structure were performed by Infrared Spectroscopy through Attenuated Total Reflectance. A higher flexural strength was found in Luxatemp and Structur with, no significant differences between this study groups. Regarding Protemp and Telio, these study groups showed a lower flexural strength when were compared with Luxatemp and Structur. These results corroborate SEM and ATR analysis because Luxatemp sample showed a regular size particle on the surface and chemically presents a long cross-linkage polymer chain. The presence of CO3, SiO2 and N-H groups as a fillers particle interacting with OH groups cause a higher flexural strength compared with another groups.

5.
Nanomaterials (Basel) ; 13(10)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37242114

RESUMEN

The use of nanoparticles (NPs) as reinforcements in polymeric coatings allows for direct interaction with the polymeric chains of the matrix, resulting in a synergistic process through physical (electrostatic forces) and chemical interactions (bond formation) for the improvement of the mechanical properties with relatively low weight concentrations of the NPs. In this investigation, different nanocomposite polymers were synthesized from the crosslinking reaction of the hydroxy-terminated polydimethylsiloxane elastomer. Different concentrations (0, 2, 4, 8, and 10 wt%) of TiO2 and SiO2 nanoparticles synthesized by the sol-gel method were added as reinforcing structures. The crystalline and morphological properties of the nanoparticles were determined through X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM). The molecular structure of coatings was through infrared spectroscopy (IR). The crosslinking, efficiency, hydrophobicity, and adhesion degree of the study groups were evaluated with gravimetric crosslinking tests, contact angle, and adhesion tests. It was observed that the crosslinking efficiency and surface adhesion properties of the different nanocomposites obtained were maintained. A slight increase in the contact angle was observed for the nanocomposites with 8 wt% compared to the polymer without reinforcements. The mechanical tests of indentation hardness and tensile strength following the ASTM E-384 and ISO 527 standards, respectively, were performed. As the nanoparticle concentration increased, a maximum increase of 157% in Vickers hardness, 71.4% in elastic modulus, and 80% in tensile strength was observed. However, the maximum elongation remained between 60 and 75%, ensuring that the composites did not become brittle.

6.
Plant Physiol Biochem ; 203: 108074, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37832367

RESUMEN

The Pepper huasteco yellow vein virus (PHYVV) is an endemic geminivirus in Mexico causing partial or total losses in the pepper crop since the damage caused by the virus has not been fully controlled. In this work, we evaluated the effect of ZnO NPs (0, 50, 100, 150, and 200 mM) as a preventive (72 h before) and curative (72 h after) treatment of PHYVV infection in two jalapeño pepper varieties. In this study, we observed a decrease in symptoms, and it could be caused by an induction of the defense system in pepper plants and a direct action on PHYVV by foliar application of ZnO NPs. Our findings suggest that ZnO NP application significantly decreased the viral titer for both varieties at 200 mM by 15.11-fold. However, this effect was different depending on the timing of application and the variety of pepper. The greatest decrease in the viral titer in the preventive treatment in both varieties was at the concentration of 200 mM (1781.17 and 274.5 times, respectively). For curative treatment in cv. Don Pancho at the concentration of 200 mM (333.33 times) and cv. Don Benito at 100 mM (43.10 folds). compared to control. Furthermore, virus mobility was generally restricted for both varieties at 100 mM (15.13-fold) compared to the control. The results possibly delineated that ZnO NPs increased plant resistance possibly by increasing POD (2.08 and 0.25 times) and SOD (0.998 and 1.38) in cv. Don Pancho and cv. Don Benito, respectively. On the other hand, in cv. Don Pancho and cv. Don Benito presented a decrease in CAT (0.61 and 0.058) and PAL (0.78 and 0.77), respectively. Taken together, we provide the first evidence to demonstrate the effect of ZnO NPs on viral symptoms depending on the plan-virus-ZnO NP interaction.


Asunto(s)
Begomovirus , Capsicum , Geminiviridae , Óxido de Zinc , Óxido de Zinc/farmacología , Geminiviridae/fisiología , Plantas
7.
Sensors (Basel) ; 12(8): 10742-58, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23112626

RESUMEN

Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0-100%. The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA) platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.


Asunto(s)
Dióxido de Carbono/análisis , Técnicas de Química Analítica/instrumentación , Técnicas de Química Analítica/métodos , Metano/análisis , Procesamiento de Señales Asistido por Computador/instrumentación , Agua/química , Algoritmos , Biocombustibles/análisis , Diseño de Equipo , Solubilidad
8.
Materials (Basel) ; 15(4)2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-35208122

RESUMEN

In this work, novel adsorbents based on 3D hierarchical silica monoliths functionalized with thiol groups were used for the removal of Hg(II) ions from an acidic aqueous solution (pH 3.5). Silica monoliths were synthesized by using two different pluronic triblock polymers (P123 and F127) to study the effect of porous structure on their sorption capacity. Before and after functionalization by grafting with 3-mercaptopropyltrimethoxysilane (MPTMS), the monoliths were characterized by several techniques, and their Hg(II) removal potential was evaluated in batch experiments at 28 °C and pH 3.5, using different initial concentrations of Hg(II) ions in water (200-500 mg L-1). The thiol groups of the monoliths calcined at 550 °C showed thermal stability up to 300 °C (from TG/DTG). The functionalized monolith synthesized with P123 polymer and polyethylene glycol showed favorable hierarchical macro-mesopores for Hg(II) adsorption. M(P123)-SH exhibited 97% removal of Hg(II) at concentration 200 mg L-1. Its maximum adsorption capacity (12.2 mmol g-1) was two times higher than that of M(F127)-SH, demonstrating that the 3D hierarchical macro-mesoporosity allowing accessibility of Hg(II) to thiol groups favors the physical and chemical adsorption of Hg(II) under slightly acidic conditions.

9.
Pharmaceutics ; 14(10)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36297503

RESUMEN

Gold nanoparticles (AuNPs) are promising nanomaterials exhibiting anti-cancer effects. Green AuNPs synthesis using plant extracts can be used to achieve stable and beneficial nanoparticles due to their content of bioactive compounds. This research aimed to synthesize and evaluate the antiproliferative and caspase-3 activity induction of green AuNPs synthesized with common mullein (V. thapsus) flowers (AuNPsME) and castor bean (R. communis) leaves (AuNPsCE) ethanolic extracts in human HT29 and SW480 colorectal cancer cells. Their effect was compared with chemically synthesized AuNPs (AuNPsCS). The extracts mainly contained p-coumaric acid (71.88-79.93 µg/g), ferulic acid (19.07-310.71 µg/g), and rutin (8.14-13.31 µg/g). The obtained nanoparticles presented typical FT-IR bands confirming the inclusion of polyphenols from V. thapsus and R. communis and spherical/quasi-spherical morphologies with diameters in the 20.06-37.14 nm range. The nanoparticles (20-200 µg/mL) showed antiproliferative effects in both cell lines, with AuNPsCE being the most potent (IC50 HT29: 110.10 and IC50SW480: 64.57 µg/mL). The AuNPsCS showed the lowest intracellular reactive oxygen species (ROS) generation in SW480 cells. All treatments induced caspase 3/7 activity to a similar or greater extent than 30 mM H2O2-treated cells. Results indicated the suitability of V. thapsus and R. communis extracts to synthesize AuNPs, displaying a stronger antiproliferative effect than AuNPsCS.

10.
Materials (Basel) ; 15(13)2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35806844

RESUMEN

The stability and mechanical properties of hydroxyapatite (HAp)/Chitosan composite materials depend on the dispersion of HAp aggregates in the chitosan matrix and on the chemical interaction between them. Therefore, hexagonal cross-sectioned HAp nanofibers were produced using a microwave-assisted hydrothermal method. Glutamic acid was used to control the HAp crystal growth; thereby, nanofibers were obtained with a preferential crystalline orientation, and they were grown along the "c" axis of HAp crystal structures. This morphology exposed the (300) and (100) crystal planes on the surface, and several phosphate groups and calcium ions were also exposed; they were able to form numerous chemical interactions with the amine, hydroxyl, and carbonyl groups of chitosan. Consequently, the final mechanical resistance of the composite materials was synergistically increased. Nanofibers were mixed with commercial chitosan using a sonotrode to improve their dispersion within the biopolymer matrix and prevent migration. The HAp nanofiber/Chitosan composite materials showed higher mechanical resistance than that observed in similar materials with the same chemical composition that were made of commercial HAp powders, which were used as reference materials. The mechanical resistance under tension of the composite materials made of nanofibers was similar to that reported for cortical bone.

11.
Materials (Basel) ; 15(21)2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-36363227

RESUMEN

The SiO2 particles system is one of the most common ways to protect colloidal metal systems, such as gold nanoparticles, from aggregation and activity loss due to their high chemical stability and low reactivity. In this study, silica green gold nanoparticles (AuNPs synthesized with mullein extract) were fabricated using two different sol-gel methods. The nanoparticles were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), Fourier Transformed Infrared (FTIR), and the antibacterial activity against pathogens (Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella enterica). Synthesis-1 nanoparticles had a kidney-shaped form and uniform distribution, while synthesis-2 nanoparticles had a spherical and non-uniform form. Characterization showed that temperature is an important factor in the distribution of AuNPs in silica; a decrease allowed the formation of Janus-type, and an increase showed a higher concentration of gold in energy-dispersive spectroscopy (EDS) analysis. Overall, similar bands of the two synthesis silica nanoparticles were observed in FTIR, while XRD spectra showed differences in the preferential growth in AuNPs depending on the synthesis. Higher antibacterial activity was observed against S. aureus, which was followed by L. monocytogenes. No differences were observed in the antibacterial activity between the two different sol-gel methods.

12.
Neuroradiol J ; 34(4): 348-354, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33678065

RESUMEN

OBJECTIVE: An abnormally decreased clivoaxial angle (CXA) is used during the clinical evaluation for corrective skull base surgery. Published normal ranges of CXA using x-ray, computed tomography, or magnetic resonance imaging (MRI) vary dramatically, especially with neck flexion or extension. The aim of this study was to use high-resolution MRI to determine the normal range of CXA in various neck positions using a reproducible measurement technique. METHODS: The CXA was measured in 10 healthy volunteers on sagittal T2 SPACE c-spine MRI in supine and prone positions and with the neck both neck and extended. CXA is strictly defined as the angle between a line along the inferior third of the dorsal clival cortex and a line from the superior/posterior cortex of the dens to the posterior/inferior corner of the C2 body. Statistical analysis was performed in all positions and included mean CXA, range, standard deviation (SD), inter-reader agreement, and group comparisons. RESULTS: The mean CXA overall was 156.92° (SD=4.23°; range 134-179°). The mean value for extension CXA was 169.20° (SD=5.81°), and the mean value for flexion CXA was 144.73° (SD=5.71°), the difference being statistically significant (p<0.0001) regardless of supine or prone position. Concordant correlations of reader measurements showed substantial agreement in the supine position at 0.96, with lower agreement in the prone position at 0.87. CONCLUSIONS: We report normal ranges for CXA in various neck positions based on 3D T2-weighted MRI, using a reproducible measurement method. There was a significant difference in the CXA values between neck extended and neck flexed positions but not between supine and prone positions.


Asunto(s)
Imagen por Resonancia Magnética , Cuello , Adulto , Vértebras Cervicales/diagnóstico por imagen , Humanos , Cuello/diagnóstico por imagen , Rango del Movimiento Articular , Valores de Referencia , Tomografía Computarizada por Rayos X
13.
J Sport Health Sci ; 10(2): 122-130, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33189894

RESUMEN

BACKGROUND: Considering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure. METHODS: Healthy adult (aged 18-35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells. RESULTS: Plasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3ß (GSK3ß), and mitogen-activated protein kinase 8 (MAPK8). CONCLUSION: Collectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease.


Asunto(s)
Vesículas Extracelulares/genética , MicroARNs/sangre , Fútbol/fisiología , Adulto , Biomarcadores/sangre , Vesículas Extracelulares/metabolismo , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Tiempo , Adulto Joven
14.
Materials (Basel) ; 14(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33804151

RESUMEN

The energy sector is one of the fields of interest for different nations around the world. Due to the current fossil fuel crisis, the scientific community develops new energy-saving experiences to address this concern. Buildings are one of the elements of higher energy consumption, so the generation of knowledge and technological development may offer solutions to this energy demand, which are more than welcome. Phase change materials (PCMs) included in building elements such as wall panels, blocks, panels or coatings, for heating and cooling applications have been shown, when heating, to increase the heat storage capacity by absorbing heat as latent heat. Therefore, the use of latent heat storage systems using phase change materials (PCMs) has been investigated within the last two decades. In the present review, the macro and micro encapsulation methods for construction materials are reviewed, the former being the most viable method of inclusion of PCMs in construction elements. In addition, based on the analysis of the existing papers on the encapsulation process of PCMs, the importance to pay more attention to the bio-based PCMs is shown, since more research is needed to process such PCMs. To determine its thermophysical and mechanical behavior at the micro and macro levels, in order to see the feasibility of substituting petroleum-based PCMs with a more environmentally friendly bio-based one, a section devoted to the excellent PCM with lightweight aggregate (PCM-LWA concrete) is presented due to the lack of description given in other reviews.

15.
Ann Surg ; 251(2): 195-200, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20054269

RESUMEN

OBJECTIVE AND BACKGROUND: Health care expenditures for 2005 in the United States were $1.9733 trillion and 15.9% of the gross domestic product (GDP). Twenty-nine percent of those expenditures were secondary to surgical revenues. Health care expenditures are increasing 2(1/2) times the rate of the general US economy and are being fed by new technologies, new medications, the aging population, more services provided per patient, defensive medicine and little tort reform, the insurance system, and the free rider problem, ie, patients are cared for as emergencies regardless of insurance coverage and legality, which all have contributed to rising health care and surgical expenditures over the last 50 years. METHODS: The purpose of this study was to project aggregate national health care expenditures, aggregate surgical health care expenditures, and the United States GDP for the years 2005-2025. Model building and existing state and national data were used. Aggregate surgical health care expenditures were computed as 29% of aggregate health care expenditures using a unique model developed by the late Dr. Francis D. Moore. The model of Dr. Moore which used 1981 federal data was verified/tested using data from UMDNJ-University Hospital, and New Jersey and national data from 2005. From 1965 to 2005 mean health care expenditures increased at 4.9% per year, and US GDP increased at a mean of 2.1% per year. RESULTS: Aggregate surgical expenditures are expected to grow from $572 billion in 2005 (4.6% of US GDP) to $912 billion (2005 dollars) in the year 2025 (7.3% of US GDP). Aggregate health care expenditures are projected to increase from $5572 per capita (15.9% of GDP) in 2005 to $8832 per capita (2005 dollars) in 2025 (25.2% of US GDP). Both surgery and national health care expenditures are expected to expand by almost 60% during the period 2005-2025. Thus, surgical health care expenditures by 2025 are likely to be 1/14 of the US economy, and health care expenditures will be (1/4) of the US economy. CONCLUSIONS: Real per capita GDP growth is relatively flat in the United States. Rising surgical health care expenditures and national health care expenditures are a significant issue for the US population. Unfortunately, programs at the state and federal level as well as private programs, for the last 50 years have not been able to slow the growth in health care expenditures. These trends are likely to continue and the effects will be: * A change in the US standard of living as surgical and health care expenditures become a larger part of the earned dollar per American especially with the current volatility of the US economy, * A rise in the cost of products made in the United States to pay the rising health care bill with a concomitant change in our national and international standard of living, and * An increasing debt and increases in federal and state taxes which will be required to maintain the current health care system, ie, Medicare, Medicaid, and the private health care insurance payment scheme, which has not changed substantially over the past 40 to 50 years. Surgeons must look at the incremental benefit of new technologies and procedures and determine which to choose if we are to slow the growth of surgical health care expenditures.


Asunto(s)
Gastos en Salud , Procedimientos Quirúrgicos Operativos/economía , Predicción , Gastos en Salud/tendencias , Modelos Econométricos , Estados Unidos
16.
Int J Mol Sci ; 11(9): 3069-86, 2010 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-20957080

RESUMEN

The aim of this article is to review current knowledge related to the synthesis and characterization of sol gel-derived SBA-16 mesoporous silicas, as well as a review of the state of the art in this issue, to take stock of knowledge about current and future applications. The ease of the method of preparation, the orderly structure, size and shape of their pores and control, all these achievable through simple changes in the method of synthesis, makes SBA-16 a very versatile material, potentially applicable in many areas of science and molecular engineering of materials.


Asunto(s)
Silicatos/síntesis química , Geles/química , Porosidad , Silicatos/química , Dióxido de Silicio/química
17.
Cells ; 9(12)2020 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-33256005

RESUMEN

Muscle stem cells (MuSCs) hold great potential as a regenerative therapeutic but have met numerous challenges in treating systemic muscle diseases. Muscle stem cell-derived extracellular vesicles (MuSC-EVs) may overcome these limitations. We assessed the number and size distribution of extracellular vesicles (EVs) released by MuSCs ex vivo, determined the extent to which MuSC-EVs deliver molecular cargo to myotubes in vitro, and quantified MuSC-EV-mediated restoration of mitochondrial function following oxidative injury. MuSCs released an abundance of EVs in culture. MuSC-EVs delivered protein cargo into myotubes within 2 h of incubation. Fluorescent labeling of intracellular mitochondria showed co-localization of delivered protein and mitochondria. Oxidatively injured myotubes demonstrated a significant decline in maximal oxygen consumption rate and spare respiratory capacity relative to untreated myotubes. Remarkably, subsequent treatment with MuSC-EVs significantly improved maximal oxygen consumption rate and spare respiratory capacity relative to the myotubes that were damaged but received no subsequent treatment. Surprisingly, MuSC-EVs did not affect mitochondrial function in undamaged myotubes, suggesting the cargo delivered is able to repair but does not expand the existing mitochondrial network. These data demonstrate that MuSC-EVs rapidly deliver proteins into myotubes, a portion of which co-localizes with mitochondria, and reverses mitochondria dysfunction in oxidatively-damaged myotubes.


Asunto(s)
Vesículas Extracelulares/patología , Peróxido de Hidrógeno/farmacología , Mitocondrias/patología , Enfermedades Mitocondriales/inducido químicamente , Enfermedades Mitocondriales/patología , Fibras Musculares Esqueléticas/patología , Células Madre/patología , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Músculo Esquelético/patología , Enfermedades Musculares/patología , Estrés Oxidativo/fisiología , Consumo de Oxígeno/fisiología
18.
Heliyon ; 6(12): e05669, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33336096

RESUMEN

Marek's disease (MD) is an alphaherpesvirus (Marek's disease virus, MDV)-induced pathology of chickens associated with paralysis, immunosuppression, neurological signs, and T-cell lymphomas. MD is controlled in poultry production via live attenuated vaccines. The purpose of the current study was to compare methods for precipitating exosomes from vaccinated and protected chicken sera (VEX) and tumor-bearing chicken sera (TEX) for biomarker analysis of vaccine-induced protection and MD lymphomas respectively. A standard polyethylene glycol (PEG, 8%) method was compared to a commercial reagent (total exosome isolation reagent, TEI) for exosome yield and RNA content. Although exosomes purified by PEG or TEI were comparable in size and morphology, TEI-reagent yielded 3-4-fold greater concentration. Relative expression of 8 out of 10 G. gallus- and MDV1-encoded miRNAs examined displayed significant difference depending upon the precipitation method used. Standard PEG yields comparable, albeit lower amounts of exosomes than the TEI-reagent and a distinctive miRNA composition.

19.
Materials (Basel) ; 13(4)2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-32093053

RESUMEN

Tridimensional cubic mesoporous silica, SBA-16, functionalized with aminopropyl groups, were employed as adsorbents for Pb2+ ion removal from aqueous solution. The adsorption capacity was investigated for the effect of pH, contact time, temperature, and concentration of 3-aminopropyltriethoxysilane (APTES) employed for adsorbent functionalization. The textural properties and morphology of the adsorbents were evaluated by N2 physisorption, small-angle X-ray diffraction (XRD), diffuse reflectance spectroscopy (UV-vis), and transmission electron microscopy (TEM). The functionalization of the SBA-16 was evaluated by elemental analysis (N), thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). Batch adsorption studies show that the total Pb2+ ions removal was archived on adsorbent having an optimized amount of aminopropyl groups (2N-SBA-16). The maximum of Pb2+ ions removal occurred at optimized adsorption conditions: pH = 5-6, contact time 40 min, and at a low initial lead concentration in solution (200 mg L-1). Under the same adsorption conditions, the amino-functionalized SBA-16 with cubic 3D unit cell structure exhibited higher adsorption capability than its SBA-15 counterpart with uniform mesoporous channels.

20.
Nutrients ; 12(11)2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33114068

RESUMEN

Childhood and adolescence are crucial stages of life for bone health. Therefore, an adequate calcium intake and a healthy life style constitute the main strategies to prevent the risk of osteoporosis-related fractures during adulthood. It has been demonstrated that inclusion of indigestible carbohydrates in foods can help improve calcium absorption in growing stages. The objective of this study was to evaluate the effect of supplementation of soluble and insoluble fibers extracted from O. ficus indica cladodes on calcium bioavailability. Male Wistar rats 4-week old were fed diets added with soluble and insoluble fibers extracted from O. ficus indica cladodes at early and late maturity stages, as the only source of calcium. The mineral content, bone mineral density (BMD), physical, microstructural, and biomechanical properties of rat femurs were determined. The bones of rats fed with diets containing a soluble fiber extracted from O. ficus indica at early and late maturity stages exhibited better bone properties (resistance to fracture, microarchitecture, and calcium content) than control rats and rats fed with an insoluble fiber from O. ficusindica cladodes at both maturity stages. As expected, based on these results, the BMD values were higher in adolescent and pubertal rats fed with a diet containing the O. ficus indica soluble fiber. These results demonstrate that the soluble fiber from O. ficus indica cladodes is indeed a valuable source of bioavailable calcium, which contributes to improve physical, densitometric, biomechanical, and microstructural properties of bone in growing rats.


Asunto(s)
Envejecimiento/efectos de los fármacos , Calcio de la Dieta/farmacocinética , Fibras de la Dieta/farmacología , Opuntia/química , Extractos Vegetales/farmacocinética , Animales , Disponibilidad Biológica , Densidad Ósea/efectos de los fármacos , Huesos/metabolismo , Masculino , Ratas , Ratas Wistar
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