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1.
Electrophoresis ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850174

RESUMEN

Selecting an adequate model to represent the mass transfer mechanisms occurring in a chromatographic process is generally complicated, which is one of the reasons why monolithic chromatography is scarcely simulated. In this study, the chromatographic separation of model proteins bovine serum albumin (BSA), ß-lactoglobulin-A, and ß-lactoglobulin-B on an anion exchange monolith was simulated based on experimental parameter determination, simultaneous model testing, and validation under three statistical criteria: retention time, dispersion accuracies, and Pearson correlation coefficient. Experimental characterization of morphologic, physicochemical, and kinetic parameters was performed through volume balances, pressure drop analysis, breakthrough curve analysis, and batch adsorptions. Free Gibbs energy indicated a spontaneous adsorption process for proteins and counterions. Dimensionless numbers were estimated based on height equivalent to a theoretical plate analysis, finding that pore diffusion controlled ß-lactoglobulin separation, whereas adsorption/desorption kinetics was the dominant mechanism for BSA. The elution profiles were modeled using the transport dispersive model and the reactive dispersive model coupled with steric mass action (SMA) isotherms because these models allowed to consider most of the mass transport mechanisms that have been described. RDM-SMA presented the most accurate simulations at pH 6.0 and at low (250 mM) and high (400 mM) NaCl concentrations. This simulation will be used as reference to forecast the purification of these proteins from bovine whey waste and to extrapolate this methodology to other monolith-based separations using these three statistical criteria that have not been used previously for this purpose.

2.
Sci Adv ; 10(14): eadl0335, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38569032

RESUMEN

The rapid growth of clean energy technologies is driving a rising demand for critical minerals. In 2022 at the 15th Conference of the Parties to the Convention on Biological Diversity (COP15), seven major economies formed an alliance to enhance the sustainability of mining these essential decarbonization minerals. However, there is a scarcity of studies assessing the threat of mining to global biodiversity. By integrating a global mining dataset with great ape density distribution, we estimated the number of African great apes that spatially coincided with industrial mining projects. We show that up to one-third of Africa's great ape population faces mining-related risks. In West Africa in particular, numerous mining areas overlap with fragmented ape habitats, often in high-density ape regions. For 97% of mining areas, no ape survey data are available, underscoring the importance of increased accessibility to environmental data within the mining sector to facilitate research into the complex interactions between mining, climate, biodiversity, and sustainability.


Asunto(s)
Hominidae , Animales , Ecosistema , Biodiversidad , Minerales , África Occidental
3.
Microbiol Spectr ; 12(1): e0337423, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38088543

RESUMEN

IMPORTANCE: Flavonoids are a group of compounds generally produced by plants with proven biological activity, which have recently beeen recommended for the treatment and prevention of diseases and ailments with diverse causes. In this study, naringenin was produced in adequate amounts in yeast after in silico design. The four genes of the involved enzymes from several organisms (bacteria and plants) were multi-expressed in two vectors carrying each two genes linked by a short viral peptide sequence. The batch kinetic behavior of the product, substrate, and biomass was described at lab scale. The engineered strain might be used in a more affordable and viable bioprocess for industrial naringenin procurement.


Asunto(s)
Flavanonas , Flavonoides , Flavonoides/metabolismo , Saccharomyces cerevisiae/metabolismo , Flavanonas/metabolismo
4.
Polymers (Basel) ; 15(20)2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37896349

RESUMEN

In this study, we synthesized and characterized pH-responsive Chitosan-AgCl-doped ZnO hybrid hydrogels and evaluated their potential for loading aquaculture bioactive compounds, and assessed their antimicrobial properties against a threatening pathogen associated with disease across a broad spectrum of warm water fish and invertebrates. Hydrogel characterization consisted of assessing morphology via SEM, composition via EDS, hydrogels' network components interactions via FT-IR and pH response through swelling behavior determinations. The swelling characterization of the synthesized hydrogels demonstrated a pH-responsive behavior, showing that low pH values caused the hydrogel polymeric network to expand and capture more of the aqueous solution. These characteristics make the synthesized hydrogels suitable for the encapsulation and controlled release of drugs and bioactive compounds in aquaculture. Chitosan_ZnO hybrid hydrogels showed great antimicrobial activity against Vibrio harveyi, even better than that of loaded PB hydrogels. Here, we provide evidence for the potential capacity of Chitosan_ZnO hybrid hydrogels for the preventive and curative treatment of diseases that impact aquaculture animal health and prevent drug resistance by bacteria.

5.
Nat Commun ; 14(1): 5022, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596311

RESUMEN

While microscopy-based cellular assays, including microfluidics, have significantly advanced over the last several decades, there has not been concurrent development of widely-accessible techniques to analyze time-dependent microscopy data incorporating phenomena such as fluid flow and dynamic cell adhesion. As such, experimentalists typically rely on error-prone and time-consuming manual analysis, resulting in lost resolution and missed opportunities for innovative metrics. We present a user-adaptable toolkit packaged into the open-source, standalone Interactive Cellular assay Labeled Observation and Tracking Software (iCLOTS). We benchmark cell adhesion, single-cell tracking, velocity profile, and multiscale microfluidic-centric applications with blood samples, the prototypical biofluid specimen. Moreover, machine learning algorithms characterize previously imperceptible data groupings from numerical outputs. Free to download/use, iCLOTS addresses a need for a field stymied by a lack of analytical tools for innovative, physiologically-relevant assays of any design, democratizing use of well-validated algorithms for all end-user biomedical researchers who would benefit from advanced computational methods.


Asunto(s)
Inteligencia Artificial , Microfluídica , Microscopía , Programas Informáticos , Células Sanguíneas
6.
Electrophoresis ; 44(24): 1989-1999, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37605320

RESUMEN

Separation of PEGylated protein mixtures into individual species is a challenging procedure, and many efforts have been focused on creating novel chromatographic supports for this purpose. In this study, a new monolithic stationary phase with hyperbranched nanostructures was chemically synthesized. For this, monoliths with a support matrix of poly (glycidyl methacrylate-co-ethylene dimethacrylate) and ethylenediamine chemistry were modified with third-generation dendrons with butyl-end groups. The new monolith was analyzed by infrared spectroscopy, confirming the dendron with butyl ligands and exhibited low mass transfer resistance as observed by breakthrough frontal analysis. This support was able to separate mono-PEG ribonuclease A from the PEGylation mixture, indicated by a single band (∼30 kDa) in the electrophoretic analysis. Moreover, the separation of mono-PEGylated positional isomers was probably observed, as the protein with ∼30 kDa was found in two separate peaks. Interestingly, the dendronized monolith allowed the separation of the reaction mixture into individual PEGylated species when using high ammonium sulfate concentrations (2 M). A correlation between the PEGylation degree and the strength of the hydrophobic interactions on the monolith was observed. This chromatographic approach combines the natural branched architecture of dendrons and the higher capabilities of the monoliths enhancing the hydrophobic surface area, and therefore the interaction between the PEGylated proteins and ligands. Thus, the novel support represents a novel platform for the purification of PEGylated from non-PEGylated proteins with biotechnological applications.


Asunto(s)
Dendrímeros , Proteínas/química , Cromatografía Liquida/métodos , Isomerismo , Polietilenglicoles/química
7.
Biomedicines ; 11(5)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37239158

RESUMEN

Exosomes are extracellular nanovesicles commonly produced by mammalian cells that in recent years have risen as a novel strategy for drug delivery systems and cancer therapy because of their innate specificity and high bioavailability. However, there are limitations that undermine their potential. Among them is the lack of mass production capacity with the current available sources and the failure to reach the intended therapeutic effect because of their insufficient uptake or their rapid clearance once administered. This review aims to show the current advances in overcoming these limitations by presenting, firstly, reported strategies to improve exosome and exosome-like nanovesicle extraction from possible novel eukaryotic sources, including animals, plants, and protozoa; and secondly, alternative modification methods that functionalize exosomes by conferring them higher targeting capacity and protection from organism defenses, which results in an increase in the attachment of ligands and cellular uptake of inorganic materials. However, even when these strategies might address some of the obstacles in their procurement and therapeutic use, there are still several aspects that need to be addressed, so several perspectives of the matter are also presented and analyzed throughout this work.

8.
Biomolecules ; 13(3)2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36979500

RESUMEN

The molecule (2S)-naringenin is a scaffold molecule with several nutraceutical properties. Currently, (2S)-naringenin is obtained through chemical synthesis and plant isolation. However, these methods have several drawbacks. Thus, heterologous biosynthesis has emerged as a viable alternative to its production. Recently, (2S)-naringenin production studies in Escherichia coli have used different tools to increase its yield up to 588 mg/L. In this study, we designed and assembled a bio-factory for (2S)-naringenin production. Firstly, we used several parametrized algorithms to identify the shortest pathway for producing (2S)-naringenin in E. coli, selecting the genes phenylalanine ammonia lipase (pal), 4-coumarate: CoA ligase (4cl), chalcone synthase (chs), and chalcone isomerase (chi) for the biosynthetic pathway. Then, we evaluated the effect of oxygen transfer on the production of (2S)-naringenin at flask (50 mL) and bench (4 L culture) scales. At the flask scale, the agitation rate varied between 50 rpm and 250 rpm. At the bench scale, the dissolved oxygen was kept constant at 5% DO (dissolved oxygen) and 40% DO, obtaining the highest (2S)-naringenin titer (3.11 ± 0.14 g/L). Using genome-scale modeling, gene expression analysis (RT-qPCR) of oxygen-sensitive genes was obtained.


Asunto(s)
Escherichia coli , Flavanonas , Escherichia coli/genética , Escherichia coli/metabolismo , Plantas/metabolismo , Expresión Génica
9.
Electrophoresis ; 44(1-2): 107-124, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36398478

RESUMEN

Bacterial membrane vesicles (BMVs) are bi-layered nanostructures derived from Gram-negative and Gram-positive bacteria. Among other pathophysiological roles, BMVs are critical messengers in intercellular communication. As a result, BMVs are emerging as a promising technology for the development of numerous therapeutic applications. Despite the remarkable progress in unveiling BMV biology and functions in recent years, their successful isolation and purification have been limited. Several challenges related to vesicle purity, yield, and scalability severely hamper the further development of BMVs for biotechnology and clinical applications. This review focuses on the current technologies and methodologies used in BMV production and purification, such as ultracentrifugation, density-gradient centrifugation, size-exclusion chromatography, ultrafiltration, and precipitation. We also discuss the current challenges related to BMV isolation, large-scale production, storage, and stability that limit their application. More importantly, the present work explains the most recent strategies proposed for overcoming those challenges. Finally, we summarize the ongoing applications of BMVs in the biotechnological field.


Asunto(s)
Bacterias , Biotecnología , Ultracentrifugación/métodos , Bacterias Grampositivas , Ultrafiltración/métodos
10.
AIDS Behav ; 27(4): 1321-1328, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36287344

RESUMEN

We aimed to validate the HIV Stigma Mechanisms Scale (HIV-SMS) in a sample of Mexican adults living with HIV, which differentiates between sources and mechanisms of stigma. Adults (n = 362) with a median age of 32 years old completed a web-based version in Spanish of the HIV-SMS as well as sociodemographic and HIV-related characteristics questionnaire. Exploratory factor analyses with weighted least squares and oblique rotation were performed to assess the construct validity of the scale. The Spanish translation for the Mexican population of the HIV-SMS has adequate internal consistency (Ω = 0.86) and demonstrated a structure similar to the original scale. After excluding the items related to community and social workers, a five-factor solution with internalized, promulgated, and anticipated stigma from family and healthcare workers showed adequate construct validity. The HIV-SMS is a valid and sensitive scale that can be used in a Mexican adult population living with HIV.


RESUMEN: El objetivo de este estudio fue validar la Escala de Mecanismos de Estigma de VIH (EME-VIH) en una muestra de adultos mexicanos que viven con VIH. Esta escala distingue entre fuentes y mecanismos de estigma. 362 adultos con una edad media de 32 años completaron vía web una versión en español de la EME-VIH así como preguntas acerca de sus características sociodemográficas y cuestiones relacionadas con el VIH. Se realizaron análisis factoriales exploratorios de mínimos cuadrados ponderados con rotación oblicua para evaluar la validez de constructo de la escala. La traducción al español de la EME-VIH para población mexicana tiene consistencia interna adecuada (Ω = 0.86) y muestra una estructura similar a la escala original. Después de excluir los ítems relacionados con trabajadores comunitarios y sociales, se encontró una solución con validez de constructo adecuada de cinco factores: estigma internalizado, promulgado y anticipado ejercido por la familia y personal de salud. La EME-VIH es una escala válida y sensible que puede usarse en población adulta mexicana que vive con VIH.


Asunto(s)
Infecciones por VIH , Humanos , Adulto , Infecciones por VIH/epidemiología , VIH , Reproducibilidad de los Resultados , Psicometría , Estigma Social , Encuestas y Cuestionarios
11.
Sensors (Basel) ; 22(19)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36236560

RESUMEN

A good approximation to power amplifier (PA) behavioral modeling requires precise baseband models to mitigate nonlinearities. Since digital predistortion (DPD) is used to provide the PA linearization, a framework is necessary to validate the modeling figures of merit support under signal conditioning and transmission restrictions. A field-programmable gate array (FPGA)-based testbed is developed to measure the wide-band PA behavior using a single-carrier 64-quadrature amplitude modulation (QAM) multiplexed by orthogonal frequency-division multiplexing (OFDM) based on long-term evolution (LTE) as a stimulus, with different bandwidths signals. In the search to provide a heuristic target approach modeling, this paper introduces a feature extraction concept to find an appropriate complexity solution considering the high sparse data issue in amplitude to amplitude (AM-AM) and amplitude to phase AM-PM models extraction, whose penalties are associated with overfitting and hardware complexity in resulting functions. Thus, experimental results highlight the model performance for a high sparse data regime and are compared with a regression tree (RT), random forest (RF), and cubic-spline (CS) model accuracy capabilities for the signal conditioning to show a reliable validation, low-complexity, according to the peak-to-average power ratio (PAPR), complementary cumulative distribution function (CCDF), coefficients extraction, normalized mean square error (NMSE), and execution time figures of merit. The presented models provide a comparison with original data that aid to compare the dimension and robustness for each surrogate model where (i) machine learning (ML)-based and (ii) CS interpolate-based where high sparse data are present, NMSE between the CS interpolated based are also compared to demonstrate the efficacy in the prediction methods with lower convergence times and complexities.


Asunto(s)
Amplificadores Electrónicos , Diseño de Equipo
12.
PLoS One ; 17(9): e0273243, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36054216

RESUMEN

Exosomes are cell-derived vesicles that present attractive characteristics such as nano size and unique structure for their use as drug delivery systems for drug therapy, biomarkers for prognostic, diagnostic and personalized treatments. So far, one of the major challenges for therapeutic applications of exosomes is the development of optimized isolation methods. In this context, aqueous two-phase systems (ATPS) have been used as an alternative method to isolate biological molecules and particles with promising expectations for exosomes. In this work, fractionation of exosomes obtained from CaCo2 cell line and culture media contaminants were individually performed in 20 polymer-polymer ATPS. The effect of design parameters such as polymer composition, molecular weight, and tie-line length (TLL) on polyethylene glycol (PEG)-Dextran, Dextran-Ficoll and PEG-Ficoll systems was studied. After partition analysis, 4 of the 20 systems presented the best exosome fractionation from contaminants under initial conditions, which were optimized via salt addition (NaCl) to a final concentration of 25 mM, to improve collection efficiency. The PEG 10,000 gmol-1 -Dextran 10,000 gmol-1 system at TLL 25% w/w with NaCl, showed the best potential isolation efficiency. Following this proposed strategy, an exosome purification factor of 2 in the top PEG-rich phase can be expected furtherly demonstrating that ATPS have the potential for the selective recovery of these promising nanovesicles.


Asunto(s)
Exosomas , Polímeros , Células CACO-2 , Dextranos/química , Ficoll , Humanos , Polietilenglicoles/química , Polímeros/química , Cloruro de Sodio/química , Agua/química
13.
Plants (Basel) ; 11(17)2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-36079566

RESUMEN

Native Mexican plants are a wide source of bioactive compounds such as pentacyclic triterpenes. Pentacyclic triterpenes biosynthesized through the mevalonate (MVA) and the 2-C-methyl-D-erythritol-phosphate (MEP) metabolic pathways are highlighted by their diverse biological activity. Compounds belonging to the oleanane, ursane, and lupane groups have been identified in about 33 Mexican plants, located geographically in the southwest of Mexico. The works addressing these findings have reported 45 compounds that mainly show antimicrobial activity, followed by anti-inflammatory, cytotoxic, anxiolytic, hypoglycemic, and growth-stimulating or allelopathic activities. Extraction by maceration and Soxhlet with organic solvents and consecutive chromatography of silica gel have been used for their whole or partial purification. Nanoparticles and nanoemulsions are the vehicles used in Mexican formulations for drug delivery of the pentacyclic triterpenes until now. Sustainable extraction, formulation, regulation, isolation, characterization, and bioassay facilities are areas of opportunity in pentacyclic triterpenes research in Mexico while the presence of plant and human resources and traditional knowledge are strengths. The present review discusses the generalities of the pentacyclic triterpene (definition, biogenic classification, and biosynthesis), a summary of the last two decades of research on the compounds identified and their evaluated bioactivity, the generalities about the extraction and purification methods used, drug delivery aspects, and a critical analysis of the advantages and limitations of research carried out in this way.

14.
Drug Alcohol Depend ; 239: 109598, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35961267

RESUMEN

BACKGROUND: Studies among the Mexican population have suggested that stigma towards persons who use drugs (PWUD) may act as a barrier to treatment seeking and contribute to negative health consequences. However, there has not been a validated scale to measure this construct. This paper aims to validate the Substance Use Stigma Mechanisms Scale (SU-SMS) in a sample of Mexican adults who use drugs. This 18-item scale was developed to differentiate substance use stigma mechanisms and learn their impact on the health and wellbeing of persons who use drugs (PWUD) in the United States. METHODS: A sample of 407 adults with a median age of 27 years old completed a web-based version in Spanish of the SU-SMS, the WHO-ASSIST screening instrument, as well as sociodemographic and substance-use-related characteristics. We performed exploratory factor analysis with weighted least squares and oblique rotation, and correlations within and between mechanisms of stigma, and substance use. RESULTS: The Spanish translation of the SU-SMS has adequate internal consistency (Ω=0.92) and the same factor structure as the original scale. A five-factor solution with internalized, enacted, and anticipated stigma from family and healthcare workers showed adequate concurrent validity. Mechanisms of stigma were correlated between them, within sources, and negatively correlated with current substance use treatment. CONCLUSIONS: The Spanish translation of the scale seems to be a valid and sensitive scale that can be used among Mexican PWUD.


Asunto(s)
Estigma Social , Trastornos Relacionados con Sustancias , Adulto , Análisis Factorial , Humanos , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
15.
Artículo en Inglés | MEDLINE | ID: mdl-35700648

RESUMEN

PEGylated protein purification with the required quality attributes has represented a bioengineering challenge and Affinity Monolith Chromatography (AMC) has never been exploited for this goal. This work reports the generation of a heparin-modified affinity monolith disk by reductive alkylation with raised ligand density for its use as chromatographic support in the separation of lysozyme PEGylation reactions (LPRs) with three different PEG sizes (1, 20 and 40 kDa). For immobilized heparin determination a modified toluidine colorimetric assay adapted to microplate format was proposed. The heparin modified-disk was able to differentiate positional isomers of 20 kDa mono-PEGylated lysozyme at neutral pH using a salt linear gradient. Identity of PEG-conjugates was verified by SDS-PAGE and positional isomers were partially characterized by peptide mapping mass spectrometry. 20 kDa mono-PEGylated lysozyme conjugate purity (99.69 ± 0.05%) was comparable with traditional chromatographic methods while productivity (0.0964 ± 0.0001 mg/mL*min) was increased up to 6.1 times compared to that obtained in heparin packed-bed affinity chromatography procedures. The proposed AMC method represents a reliable, efficient, easy-handling, fast and single-step operation for the analysis or preparative isolation of PEGylated proteins containing a heparin binding domain.


Asunto(s)
Heparina , Muramidasa , Antivirales , Cromatografía , Electroforesis en Gel de Poliacrilamida , Muramidasa/química , Polietilenglicoles/química
16.
Chemosphere ; 303(Pt 2): 135154, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35640689

RESUMEN

Air is one of the target matrices of the Global Monitoring Plan (GMP) of the Stockholm Convention to determine concentrations and transport of Persistent Organic Pollutants (POPs). Mexico participates in the GMP for POPs in ambient air through the AIR-Global Environment Facility (GEF) program. The objective of this study was to analyze the results of POPs monitoring of air samples collected in Los Mochis, Sinaloa, Mexico, between 2017 and 2018. Passive samplers were used for the determination of chlorinated basic POPs, indicator polychlorinated biphenyls (Ind. PCBs), polybrominated biphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs). A principal component analysis was applied to determine relationships between pollutants and groups present in the ambient air of the rural study area. Of the total POPs analyzed, 85.56% were detected in ambient air samples from Mexico. Organochlorine compounds, as DDT derivatives, were identified mainly, as well as PBDEs, PCDDs, and PCDFs. The prevalence of compounds differed according to the seasonality of sampling, with no change in average concentration between monitoring years.


Asunto(s)
Contaminantes Ambientales , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Dibenzofuranos Policlorados/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Éteres Difenilos Halogenados/análisis , México , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análisis
17.
PLoS One ; 17(4): e0266507, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35390074

RESUMEN

The Eating Disorder Examination Questionnaire is a widely used self-report questionnaire for eating disorders. An Eating Disorder Examination Questionnaire model that is not lacking in relevant content has been supported in three different samples, but existing studies on this model present shortcomings regarding generalizations to the general population. Therefore, the general purpose of the current research was to test the reliability and interpretation validity of the Eating Disorder Examination Questionnaire 6.0 scores in adults of both sexes from the Mexican general population. After translating, adapting, and assessing the Eating Disorder Examination Questionnaire 6.0 in the target population through three pilot studies, we conducted two independent studies. In Study 1, 684 women and 433 men aged 18-83 participated, whereas in Study 2, 591 women and 382 men aged 18-86 did it. They answered the Eating Disorder Examination Questionnaire 6.0 and a measure of either body dissatisfaction (Study 1) or self-esteem (Study 2). According to confirmatory factor analyses, the 14-item Eating Disorder Examination Questionnaire model that we tested fit acceptably for the four samples (two female, two male) and was invariant across sex. All 14-item Eating Disorder Examination Questionnaire 6.0 scores were reliable according to Cronbach's alpha and McDonald's omega, except for only one factor score in men. Pearson's correlations of the 14-item Eating Disorder Examination Questionnaire 6.0 scores with body dissatisfaction and self-esteem were positive and negative, respectively. This new Latin American Spanish translation of the Eating Disorder Examination Questionnaire 6.0 works broadly as expected and provides evidence to extend the generalization of previous studies to the general population. Thus, the present translation of the Eating Disorder Examination Questionnaire 6.0 may be a valuable tool in the field of eating disorders for researchers and practitioners studying or serving Latin American Spanish speakers of either sex from the general population.


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos , Traducciones , Adulto , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Femenino , Humanos , Masculino , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
18.
Lab Chip ; 22(8): 1565-1575, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35315465

RESUMEN

Characterization of blood flow rheology in hematological disorders is critical for understanding disease pathophysiology. Existing methods to measure blood rheological parameters are limited in their physiological relevance, and there is a need for new tools that focus on the microcirculation and extract properties at finer resolution than overall flow resistance. Herein, we present a method that combines microfluidic systems and powerful object-tracking computational technologies with mathematical modeling to separate the red blood cell flow profile into a bulk component and a wall component. We use this framework to evaluate differential contributions of effective viscosity and wall friction to the overall resistance in blood from patients with sickle cell disease (SCD) under a range of oxygen tensions. Our results demonstrate that blood from patients with SCD exhibits elevated frictional and viscous resistances at all physiologic oxygen tensions. Additionally, the viscous resistance increases more rapidly than the frictional resistance as oxygen tension decreases, which may confound analyses that extract only flow velocities or overall flow resistances. Furthermore, we evaluate the impact of transfusion treatments on the components of the resistance, revealing patient variability in blood properties that may improve our understanding of the heterogeneity of clinical responses to such treatments. Overall, our system provides a new method to analyze patient-specific blood properties and can be applied to a wide range of hematological and vascular disorders.


Asunto(s)
Anemia de Células Falciformes , Técnicas Analíticas Microfluídicas , Fricción , Humanos , Oxígeno , Extractos Vegetales , Reología , Viscosidad
19.
Sensors (Basel) ; 22(3)2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35161921

RESUMEN

The signal conditioning treatment to achieve good relation of power with radio-frequency (RF) conversion in conventional transceiver systems require precise baseband models. A developed framework is built to provide a demonstration of the modeling figures of merit with orthogonal frequency division multiplexing (OFDM) support under signal conditioning and transmission restrictions to waveforms with high peak to average power ratio (PAPR) in practical applications. Therefore, peak and average power levels have to be limited to correct high PAPR for a better suited correction power from the amplifier that can lead to compression or clipping in the signal of interest. This work presents an alternative joint crest factor reduction (CFR) algorithm to correct the performance of PAPR. A real-time field-programmable gate array (FPGA) testbed is developed to characterize and measure the behavior of an amplifier using a single-carrier 64-QAM OFDM based on long-term evolution (LTE) downlink at 2.40 GHz as stimulus, across wide modulation bandwidths. The results demonstrate that the CFR accuracy capabilities for the signal conditioning show a reliable clipping reduction to give a smooth version of the clipping signal and provide a factor of correction for the unwanted out-of-band emission validated according to the adjacent channel power ratio (ACPR), PAPR, peak power, complementary cumulative distribution function (CCDF), and error vector magnitude (EVM) figures of merit.

20.
Electrophoresis ; 43(1-2): 109-118, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34791693

RESUMEN

Nanotechnology is one of the most promising technologies of the 21st century, and it is now presenting an enormous impact on target drug delivery. In this context, the recent use of natural vesicle-like nanoparticles such as extracellular vesicles (i.e., exosomes, microvesicles, and apoptotic bodies) and virus-like particles is rendering encouraging results mostly because these delivery systems present cargo versatility, favorable body circulating advantages, biocompatibility, immunogenicity, and the capacity to be modified superficially to increase their affinity to a certain target or to control their entrance to the cell. However, some of the biggest challenges toward their clinical implementation are poorly standardized processing operations due to their inherent heterogeneity and expensive, long-lasting, and difficult to scale isolation procedures that can also affect the stability of the particles. Under these circumstances, chromatographic procedures represent an attractive and favorable alternative to overcome their downstream processing. Moreover, even when standardized chromatographic purification protocols are still in development, great achievements have been made using size exclusion, ionic exchange, hydrophobic interaction, and affinity protocols, mostly because of the correct harnessing of the nanovesicle membrane properties. In this sense, this review focuses on presenting the current understanding on the most promising therapeutic biological nanoparticles and the chromatographic isolation approaches employed in their recovery, providing at the same time recent findings and a general overview of the aspects that might impact the outcome of chromatographic techniques for this application.


Asunto(s)
Sistemas de Liberación de Medicamentos , Terapia Molecular Dirigida , Nanopartículas , Vesículas Extracelulares , Nanotecnología
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