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1.
RSC Adv ; 14(30): 21874-21886, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38984260

RESUMEN

The ethanolic extract of Nectandra reticulata contains a high amount of quercetin-3-O-rhamnoside (quercitrin) that has exhibited a significant activity toward Alzheimer's disease, specifically with LXR receptors. In this work, a methodology was validated following the specifications of the International Conference of Harmonization in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy (recovery), repeatability (intra-assay), intermediate precision (intra-laboratory), reproducibility (inter-laboratory), robustness, and specificity. The effect of location (Oiba, Granada, and Chiquinquira) and the extraction method (percolation, maceration, and ultrasound-assisted extraction) towards the chromatographic profile and quercitrin recovery was studied. Furthermore, a Box-Behnken design was conducted to optimize quercitrin extraction and extraction yield by ultrasonic-assisted extraction. The chromatographic method was validated, with a linear range from 5 to 180 mg quercitrin per L, LOD 0.26 mg L-1, and LOQ 0.86 mg L-1. Accuracy [recovery of 93.8% (w/w)], repeatability (relative standard deviation, RSD, 3.3%), intermediate precision (RSD 5.4%), and reproducibility (RSD 1.4%) were within the acceptable values. The method was robust and specific, except for the variation in the formic acid concentration. The location had a greater influence than the extraction method towards both the chromatographic profile and quercitrin recovery. Quercitrin extraction was maximized at 60% (v/v) ethanol and 50 °C, independent of the solvent : material ratio used. The highest yield values were achieved at 60% (v/v) ethanol and 50 °C, with a solvent : material ratio of 40 mL g-1.

2.
Sensors (Basel) ; 24(3)2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38339659

RESUMEN

Hybrid pixel detectors have become indispensable at synchrotron and X-ray free-electron laser facilities thanks to their large dynamic range, high frame rate, low noise, and large area. However, at energies below 3 keV, the detector performance is often limited because of the poor quantum efficiency of the sensor and the difficulty in achieving single-photon resolution due to the low signal-to-noise ratio. In this paper, we address the quantum efficiency of silicon sensors by refining the design of the entrance window, mainly by passivating the silicon surface and optimizing the dopant profile of the n+ region. We present the measurement of the quantum efficiency in the soft X-ray energy range for silicon sensors with several process variations in the fabrication of planar sensors with thin entrance windows. The quantum efficiency for 250 eV photons is increased from almost 0.5% for a standard sensor to up to 62% as a consequence of these developments, comparable to the quantum efficiency of backside-illuminated scientific CMOS sensors. Finally, we discuss the influence of the various process parameters on quantum efficiency and present a strategy for further improvement.

3.
Research (Wash D C) ; 6: 0254, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38023417

RESUMEN

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left ventricle. There is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left ventricular biopsies from living donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observed no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features varied considerably among individuals in our population with no relevant relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human ventricular electrophysiology and to assess the effects of interindividual differences in specific features of CX43 and fibrosis on conduction velocity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. These mechanisms underlying high arrhythmic risk in some individuals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its potential as a proarrhythmic factor at the individual level, especially when combined with increased fibrosis.

4.
Front Nutr ; 10: 1231049, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37720375

RESUMEN

This study aimed to investigate the macronutrient and carotenoid content of red and yellow Coffea arabica var. Caturra pulp, a by-product of coffee processing in Colombia. The study employed ultra-sound-assisted extraction (UAE) to extract carotenoids, and a 23 factorial design was used to evaluate the effects of pulp color, biomass-solvent ratio, and solvent mixture composition on carotenoid content and extraction yield. The condition that provided the highest carotenoid extraction was further encapsulated by spray drying and added to a dairy product. The results showed that coffee pulp has significant dietary fiber content and high levels of carotenoids, with yellow pulp having a higher content than red pulp. Lutein isomers and lutein esters were the most abundant carotenoids found in both red and yellow coffee pulp. The highest carotenoid extraction was achieved using a 1:40 (g/mL) biomass:solvent ratio and a 20:80% v/v Ethanol:Ethyl Acetate solvent mixture for the yellow pulp. The carotenoid extract also demonstrated high encapsulation efficiency (46.57 ± 4.03%) and was found to be stable when added to a fermented milk product. This study presents an alternative solution for utilizing coffee by-products in Colombia, which could positively impact the families of over half a million Colombian coffee producers.

5.
J Synchrotron Radiat ; 30(Pt 1): 227-234, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36601941

RESUMEN

The JUNGFRAU 4-megapixel (4M) charge-integrating pixel-array detector, when operated at a full 2 kHz frame rate, streams data at a rate of 17 GB s-1. To operate this detector for macromolecular crystallography beamlines, a data-acquisition system called Jungfraujoch was developed. The system, running on a single server with field-programmable gate arrays and general-purpose graphics processing units, is capable of handling data produced by the JUNGFRAU 4M detector, including conversion of raw pixel readout to photon counts, compression and on-the-fly spot finding. It was also demonstrated that 30 GB s-1 can be handled in performance tests, indicating that the operation of even larger and faster detectors will be achievable in the future. The source code is available from a public repository.


Asunto(s)
Programas Informáticos , Sincrotrones , Rayos X , Radiografía , Cristalografía por Rayos X
6.
Molecules ; 27(24)2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36557871

RESUMEN

Recently, natural antioxidants for the food industry have become an important focus. Cashew nut-shell liquid (CNSL) is composed of compounds that can act as natural antioxidants in food systems. The aim of this work was to evaluate the potential of CNSL and its components to act as natural antioxidants in a bulk oil system. CNSL was treated with calcium hydroxide to obtain two fractions [cardol/cardanols acid fraction (CCF) and anacardic acid fraction (AF)]. CNSL, FF and AF were analyzed by thin-layer chromatography and Fourier-transform infrared spectroscopy. The protective effects of CNSL, CCF and AF were tested in terms of the peroxide value of bulk soybean oil in accelerated assays and were compared against controls with and without synthetic antioxidants (CSA and CWA). CNLS, CCF, AF and CSA were tested at 200 mg/kg soybean oil by incubation at 30, 40, 50 and 60 °C for five days. The activation energy (Ea) for the production of peroxides was calculated by using the linearized Arrhenius equation. Thin-layer chromatography and Fourier-transform infrared spectroscopy revealed that (i) CNSL contained cardanols, anacardic acids, and cardols; (ii) CCF contained cardanols and cardols; and (iii) AF contained anacardic acids. CSA (Ea 35,355 J/mol) was the most effective antioxidant, followed by CCF (Ea 31,498 J/mol) and by CNSL (Ea 26,351 J/mol). AF exhibited pro-oxidant activity (Ea 8339 J/mol) compared with that of CWA (Ea 15,684 J/mol). Therefore, cardols and cardanols from CNSL can be used as a natural antioxidant in soybean oil.


Asunto(s)
Anacardium , Anacardium/química , Antioxidantes/química , Aceite de Soja/análisis , Fenoles/química , Ácidos Anacárdicos/farmacología , Ácidos Anacárdicos/química , Nueces/química
7.
iScience ; 25(2): 103822, 2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35198884

RESUMEN

Age-related fibrosis in the left ventricle (LV) has been mainly studied in animals by assessing collagen content. Using second-harmonic generation microscopy and image processing, we evaluated amount, aggregation and spatial distribution of LV collagen in young to old pigs, and middle-age and elder living donors. All collagen features increased when comparing adult and old pigs with young ones, but not when comparing adult with old pigs or middle-age with elder individuals. Remarkably, all collagen parameters strongly correlated with lipofuscin, a biological age marker, in humans. By building patient-specific models of human ventricular tissue electrophysiology, we confirmed that amount and organization of fibrosis modulated arrhythmia vulnerability, and that distribution should be accounted for arrhythmia risk assessment. In conclusion, we characterize the age-associated changes in LV collagen and its potential implications for ventricular arrhythmia development. Consistency between pig and human results substantiate the pig as a relevant model of age-related LV collagen dynamics.

8.
Molecules ; 26(24)2021 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-34946598

RESUMEN

Phenolic compounds from mango (M. indica) seed kernels (MSK) var. Sugar were obtained using supercritical CO2 and EtOH as an extraction solvent. For this purpose, a central composite design was carried out to evaluate the effect of extraction pressure (11-21 MPa), temperature (40-60 °C), and co-solvent contribution (5-15% w/w EtOH) on (i) extraction yield, (ii) oxidative stability (OS) of sunflower edible oil (SEO) with added extract using the Rancimat method, (iii) total phenolics content, (iv) total flavonoids content, and (v) DPPH radical assay. The most influential variable of the supercritical fluid extraction (SFE) process was the concentration of the co-solvent. The best OS of SEO was reached with the extract obtained at 21.0 MPa, 60 °C and 15% EtOH. Under these conditions, the extract increased the OS of SEO by up to 6.1 ± 0.2 h (OS of SEO without antioxidant, Control, was 3.5 h). The composition of the extract influenced the oxidative stability of the sunflower edible oil. By SFE it was possible to obtain extracts from mango seed kernels (MSK) var. Sugar that transfer OS to the SEO. These promissory extracts could be applied to foods and other products.


Asunto(s)
Antioxidantes/farmacología , Mangifera/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Aceites de Plantas/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Cromatografía con Fluido Supercrítico , Fenoles/química , Fenoles/aislamiento & purificación , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación
9.
Aging Cell ; 20(7): e13383, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34092006

RESUMEN

Aging is the main risk factor for cardiovascular diseases. In humans, cardiac aging remains poorly characterized. Most studies are based on chronological age (CA) and disregard biological age (BA), the actual physiological age (result of the aging rate on the organ structure and function), thus yielding potentially imperfect outcomes. Deciphering the molecular basis of ventricular aging, especially by BA, could lead to major progresses in cardiac research. We aim to describe the transcriptome dynamics of the aging left ventricle (LV) in humans according to both CA and BA and characterize the contribution of microRNAs, key transcriptional regulators. BA is measured using two CA-associated transcriptional markers: CDKN2A expression, a cell senescence marker, and apparent age (AppAge), a highly complex transcriptional index. Bioinformatics analysis of 132 LV samples shows that CDKN2A expression and AppAge represent transcriptomic changes better than CA. Both BA markers are biologically validated in relation to an aging phenotype associated with heart dysfunction, the amount of cardiac fibrosis. BA-based analyses uncover depleted cardiac-specific processes, among other relevant functions, that are undetected by CA. Twenty BA-related microRNAs are identified, and two of them highly heart-enriched that are present in plasma. We describe a microRNA-gene regulatory network related to cardiac processes that are partially validated in vitro and in LV samples from living donors. We prove the higher sensitivity of BA over CA to explain transcriptomic changes in the aging myocardium and report novel molecular insights into human LV biological aging. Our results can find application in future therapeutic and biomarker research.


Asunto(s)
Envejecimiento/genética , Biomarcadores/metabolismo , Ventrículos Cardíacos/metabolismo , MicroARNs/genética , Femenino , Humanos , Masculino
10.
Rev Colomb Obstet Ginecol ; 72(1): 24-32, 2021 Mar 30.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33878811

RESUMEN

Objective: To describe the safety of early discharge in the first 12 hours of the postoperative period in women undergoing laparoscopic hysterectomy for benign uterine disease. Materials and methods: Descriptive historical cohort study. The study included all women undergoing laparoscopic hysterectomy due to benign disease and discharged after 12 hours of the procedure in a high complexity hospital in Bogota Colombia, between January 2013 and April 2019. Patients with comorbidities (diabetes, cardiovascular disease and chronic obstructive pulmonary disease) mobility limitations and intraoperative complications were excluded. Consecutive sampling was used. The variables assessed included demographics and safety variables such as readmission through the emergency service and complications classified according to the Dindo scale on the fifteenth postoperative day. A descriptive analysis is made. Results: Of 860 laparoscopic hysterectomies performed during the study period, 67 (7.8%) met the selection criteria. Eleven patients (16.4%) were readmitted through the emergency service, one (9%) due to active bleeding, and two (18%) because of urinary symptoms. There were six (8.9%) postoperative complications, including vaginal vault hematoma in two patients (2.9%), hemoperitoneum in two cases (2,9%), one (1.4%) urinary infection and one (1.4%) ureteral injury; four patients (5.9%) required hospitalization and were classified as stage IIIb on the Dindo scale. Conclusions: Early discharge emerges as an alternative to in-hospital care for this type of population. Randomized controlled studies are needed to produce additional evidence regarding this management approach.


Objetivo: describir la seguridad del alta en las primeras 12 horas del posoperatorio en mujeres cometidas histerectomía por laparoscopia por patología benigna de útero. Materiales y métodos: estudio de cohorte histórica descriptiva. Se incluyeron todas las mujeres llevadas a histerectomía laparoscópica por patología benigna, quienes fueron dadas de alta después de 12 horas del procedimiento en un hospital de alta complejidad en Bogotá, Colombia, entre enero del 2013 y abril del 2019. Se excluyeron pacientes con comorbilidades (diabetes, enfermedad cardiovascular y pulmonar obstructiva crónica), limitaciones para la movilización y aquellas que presentaron complicaciones intraoperatorias. Se realizó un muestreo consecutivo. Se evaluaron variables demográficas, y como variables de seguridad, el reingreso por urgencias y complicaciones clasificadas según la escala de Dindo a los 15 días del postoperatorio. Se hace análisis descriptivo. Resultados: durante el período de estudio se realizaron 860 histerectomías por laparoscopia, de estas, 67 (7,8%) cumplieron con los criterios de selección. Once pacientes (16,4%) reingresaron por el servicio de urgencias, de las cuales, siete (63,6%) acudieron por dolor, una (9%) por sangrado activo, una (9%) por fiebre, y dos (18%) por síntomas urinarios. Se presentaron seis (8,9%) complicaciones postoperatorias de las cuales dos pacientes (2,9%) tuvieron hematoma de cúpula vaginal, dos (2,9%) hemoperitoneo, una (1,4%) infección urinaria y una (1,4%) lesión ureteral; cuatro pacientes (5,9%) requirieron hospitalización, estas últimas se clasificaron en el estadio IIIb de Dindo. Conclusiones: el alta temprana surge como alternativa al cuidado hospitalario para este tipo de población. Se requieren estudios con grupo control y asignación aleatoria para aportar mejor evidencia respecto a este manejo.


Asunto(s)
Laparoscopía , Alta del Paciente , Estudios de Cohortes , Colombia/epidemiología , Femenino , Humanos , Histerectomía/efectos adversos , Readmisión del Paciente , Estudios Retrospectivos
11.
Catheter Cardiovasc Interv ; 98(2): E205-E212, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-33759362

RESUMEN

OBJECTIVE: To determine utilization and reimbursement trends of coronary revascularization procedures in the US Medicare population from 2000 to 2018. BACKGROUND: US Medicare population is increasing, and coronary revascularization decreased in the 2000s. METHODS: This is a population-based, cross sectional study of US Medicare beneficiaries from 2010 to 2018. The Centers for Medicare and Medicaid Services' database was queried for revascularization procedures using the coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) current procedural terminology (CPT) codes. Trends in Medicare enrollees, PCIs, CABGs, and physician reimbursements were analyzed. RESULTS: Total utilization and reimbursement decreased for both revascularization procedures. The national CABG and PCI utilization per enrollee has decreased by 40.7% (best fit line: b coefficient, 95% CI; -0.297, -0.358 to -0.235) and 26.4% (best fit line: -0.229, -0.373 to -0.0858), respectively. For CABG, annual Medicare payout per enrollee and physician compensation per procedure has decreased by 49.3% (best fit line: -0.250, -0.315 to -0.185) and 14.5% (best fit line: -11.54, -15.62 to -7.452), respectively, and for PCI, decreased by 53.3% (best fit line: -0.373, -0.560 to -0.186) and 36.6% (best fit line: -34.15, -49.35 to -18.95), respectively. Amongst the states, there was significant variability in procedure utilization, and CABG reimbursement rates but minimal variability in PCI reimbursement rates. CONCLUSION: Even though the US population has aged, revascularization utilization and reimbursement continue to decline. Advancement in medical intervention strategies, particularly non-surgical management, may account for these trends. Further understanding of these trends will allow health systems to tailor resources to the aging population.


Asunto(s)
Intervención Coronaria Percutánea , Anciano , Estudios Transversales , Humanos , Resultado del Tratamiento , Estados Unidos
12.
Sensors (Basel) ; 21(4)2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33672262

RESUMEN

Chromium compensated GaAs or GaAs:Cr sensors provided by the Tomsk State University (Russia) were characterized using the low noise, charge integrating readout chip JUNGFRAU with a pixel pitch of 75 × 75 µm2 regarding its application as an X-ray detector at synchrotrons sources or FELs. Sensor properties such as dark current, resistivity, noise performance, spectral resolution capability and charge transport properties were measured and compared with results from a previous batch of GaAs:Cr sensors which were produced from wafers obtained from a different supplier. The properties of the sample from the later batch of sensors from 2017 show a resistivity of 1.69 × 109 Ω/cm, which is 47% higher compared to the previous batch from 2016. Moreover, its noise performance is 14% lower with a value of (101.65 ± 0.04) e- ENC and the resolution of a monochromatic 60 keV photo peak is significantly improved by 38% to a FWHM of 4.3%. Likely, this is due to improvements in charge collection, lower noise, and more homogeneous effective pixel size. In a previous work, a hole lifetime of 1.4 ns for GaAs:Cr sensors was determined for the sensors of the 2016 sensor batch, explaining the so-called "crater effect" which describes the occurrence of negative signals in the pixels around a pixel with a photon hit due to the missing hole contribution to the overall signal causing an incomplete signal induction. In this publication, the "crater effect" is further elaborated by measuring GaAs:Cr sensors using the sensors from 2017. The hole lifetime of these sensors was 2.5 ns. A focused photon beam was used to illuminate well defined positions along the pixels in order to corroborate the findings from the previous work and to further characterize the consequences of the "crater effect" on the detector operation.

13.
Rev. colomb. obstet. ginecol ; 72(1): 24-32, Jan.-Mar. 2021. tab, graf
Artículo en Español | LILACS | ID: biblio-1251610

RESUMEN

RESUMEN Objetivo: describir la seguridad del alta en las primeras 12 horas del posoperatorio en mujeres cometidas histerectomía por laparoscopia por patología benigna de útero. Materiales y métodos: estudio de cohorte histórica descriptiva. Se incluyeron todas las mujeres llevadas a histerectomía laparoscópica por patología benigna, quienes fueron dadas de alta después de 12 horas del procedimiento en un hospital de alta complejidad en Bogotá, Colombia, entre enero del 2013 y abril del 2019. Se excluyeron pacientes con comorbilidades (diabetes, enfermedad cardiovascular y pulmonar obstructiva crónica), limitaciones para la movilización y aquellas que presentaron complicaciones intraoperatorias. Se realizó un muestreo consecutivo. Se evaluaron variables demográficas, y como variables de seguridad, el reingreso por urgencias y complicaciones clasificadas según la escala de Dindo a los 15 días del postoperatorio. Se hace análisis descriptivo. Resultados: durante el período de estudio se realizaron 860 histerectomías por laparoscopia, de estas, 67 (7,8%) cumplieron con los criterios de selección. Once pacientes (16,4%) reingresaron por el servicio de urgencias, de las cuales, siete (63,6%) acudieron por dolor, una (9%) por sangrado activo, una (9%) por fiebre, y dos (18%) por síntomas urinarios. Se presentaron seis (8,9%) complicaciones postoperatorias de las cuales dos pacientes (2,9%) tuvieron hematoma de cúpula vaginal, dos (2,9%) hemoperitoneo, una (1,4%) infección urinaria y una (1,4%) lesión ureteral; cuatro pacientes (5,9%) requirieron hospitalización, estas últimas se clasificaron en el estadio IIIb de Dindo. Conclusiones: el alta temprana surge como alternativa al cuidado hospitalario para este tipo de población. Se requieren estudios con grupo control y asignación aleatoria para aportar mejor evidencia respecto a este manejo.


ABSTRACT Objective: To describe the safety of early discharge in the first 12 hours of the postoperative period in women undergoing laparoscopic hysterectomy for benign uterine disease. Materials and methods: Descriptive historical cohort study. The study included all women undergoing laparoscopic hysterectomy due to benign disease and discharged after 12 hours of the procedure in a high complexity hospital in Bogota Colombia, between January 2013 and April 2019. Patients with comorbidities (diabetes, cardiovascular disease and chronic obstructive pulmonary disease) mobility limitations and intraoperative complications were excluded. Consecutive sampling was used. The variables assessed included demographics and safety variables such as readmission through the emergency service and complications classified according to the Dindo scale on the fifteenth postoperative day. A descriptive analysis is made. Results: Of 860 laparoscopic hysterectomies performed during the study period, 67 (7.8%) met the selection criteria. Eleven patients (16.4%) were readmitted through the emergency service, one (9%) due to active bleeding, and two (18%) because of urinary symptoms. There were six (8.9%) postoperative complications, including vaginal vault hematoma in two patients (2.9%), hemoperitoneum in two cases (2,9%), one (1.4%) urinary infection and one (1.4%) ureteral injury; four patients (5.9%) required hospitalization and were classified as stage IIIb on the Dindo scale. Conclusions: Early discharge emerges as an alternative to in-hospital care for this type of population. Randomized controlled studies are needed to produce additional evidence regarding this management approach


Asunto(s)
Humanos , Femenino , Laparoscopía , Histerectomía , Procedimientos Quirúrgicos Ambulatorios
14.
Food Chem ; 349: 129207, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33601282

RESUMEN

The simultaneous effect of genotype, agro-climatic conditions, and cooking method was evaluated towards the contents of vitamin C, protein, and soluble, insoluble, and total dietary fibre in potato tubers from the Group Phureja. Within the tested treatments, vitamin C was affected the most (9.4-85.1 mg/100 g DW), followed by insoluble dietary fibre (3.9-16.6 g/100 DW), soluble dietary fibre (1.0-3.9 g/100 g DW), total dietary fibre (3.6-fold change), and protein (1.7-4.3 g/100 g DW). The cooking method had a high effect on the variability of the contents of vitamin C, protein, insoluble dietary fibre, and total dietary fibre (74.2-92.8% of the total variance). In contrast, not only the cooking method, but also the agro-climatic conditions had a high effect on the content of soluble dietary fibre (32.6 and 34.8% of the total variance, respectively). Total dietary fibre had a protective effect on vitamin C upon cooking.


Asunto(s)
Ácido Ascórbico/análisis , Clima , Culinaria/métodos , Genotipo , Proteínas de Plantas/análisis , Solanum tuberosum/química , Solanum tuberosum/genética , Agricultura , Tubérculos de la Planta/química , Solanum tuberosum/crecimiento & desarrollo
15.
Sci Rep ; 10(1): 19941, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33203905

RESUMEN

Cardiac tissue slices preserve the heterogeneous structure and multicellularity of the myocardium and allow its functional characterization. However, access to human ventricular samples is scarce. We aim to demonstrate that slices from small transmural core biopsies collected from living donors during routine cardiac surgery preserve structural and functional properties of larger myocardial specimens, allowing accurate electrophysiological characterization. In pigs, we compared left ventricular transmural core biopsies with transmural tissue blocks from the same ventricular region. In humans, we analyzed transmural biopsies and papillary muscles from living donors. All tissues were vibratome-sliced. By histological analysis of the transmural biopsies, we showed that tissue architecture and cellular organization were preserved. Enzymatic and vital staining methods verified viability. Optically mapped transmembrane potentials confirmed that action potential duration and morphology were similar in pig biopsies and tissue blocks. Action potential morphology and duration in human biopsies and papillary muscles agreed with published ranges. In both pigs and humans, responses to increasing pacing frequencies and ß-adrenergic stimulation were similar in transmural biopsies and larger tissues. We show that it is possible to successfully collect and characterize tissue slices from human myocardial biopsies routinely extracted from living donors, whose behavior mimics that of larger myocardial preparations both structurally and electrophysiologically.


Asunto(s)
Potenciales de Acción , Electrofisiología Cardíaca , Fenómenos Electrofisiológicos , Ventrículos Cardíacos/fisiopatología , Donadores Vivos , Potenciales de la Membrana , Animales , Humanos , Porcinos
16.
Biomolecules ; 10(9)2020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32957719

RESUMEN

Cardiomyocytes' geometry and connexin 43 (CX43) amount and distribution are structural features that play a pivotal role in electrical conduction. Their quantitative assessment is of high interest in the study of arrhythmias, but it is usually hampered by the lack of automatic tools. In this work, we propose a software algorithm (Myocyte Automatic Retrieval and Tissue Analyzer, MARTA) to automatically detect myocytes from fluorescent microscopy images of cardiac tissue, measure their morphological features and evaluate the expression of CX43 and its degree of lateralization. The proposed software is based on the generation of cell masks, contouring of individual cells, enclosing of cells in minimum area rectangles and splitting of these rectangles into end-to-end and middle compartments to estimate CX43 lateral-to-total ratio. Application to human ventricular tissue images shows that mean differences between automatic and manual methods in terms of cardiomyocyte length and width are below 4 µm. The percentage of lateral CX43 also agrees between automatic and manual evaluation, with the interquartile range approximately covering from 3% to 30% in both cases. MARTA is not limited by fiber orientation and has an optimized speed by using contour filtering, which makes it run hundreds of times faster than a trained expert. Developed for CX43 studies in the left ventricle, MARTA is a flexible tool applicable to morphometric and lateralization studies of other markers in any heart chamber or even skeletal muscle. This open-access software is available online.


Asunto(s)
Conexina 43/metabolismo , Microscopía Fluorescente/métodos , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Algoritmos , Animales , Humanos , Masculino , Miocardio/citología , Miocitos Cardíacos/citología , Ratas Wistar , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo
17.
Struct Dyn ; 7(1): 014305, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32128347

RESUMEN

In this paper, we present a data workflow developed to operate the adJUstiNg Gain detector FoR the Aramis User station (JUNGFRAU) adaptive gain charge integrating pixel-array detectors at macromolecular crystallography beamlines. We summarize current achievements for operating at 9 GB/s data-rate a JUNGFRAU with 4 Mpixel at 1.1 kHz frame-rate and preparations to operate at 46 GB/s data-rate a JUNGFRAU with 10 Mpixel at 2.2 kHz in the future. In this context, we highlight the challenges for computer architecture and how these challenges can be addressed with innovative hardware including IBM POWER9 servers and field-programmable gate arrays. We discuss also data science challenges, showing the effect of rounding and lossy compression schemes on the MX JUNGFRAU detector images.

18.
J Synchrotron Radiat ; 26(Pt 4): 1226-1237, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31274448

RESUMEN

Recent advances in segmented low-gain avalanche detectors (LGADs) make them promising for the position-sensitive detection of low-energy X-ray photons thanks to their internal gain. LGAD microstrip sensors fabricated by Fondazione Bruno Kessler have been investigated using X-rays with both charge-integrating and single-photon-counting readout chips developed at the Paul Scherrer Institut. In this work it is shown that the charge multiplication occurring in the sensor allows the detection of X-rays with improved signal-to-noise ratio in comparison with standard silicon sensors. The application in the tender X-ray energy range is demonstrated by the detection of the sulfur Kα and Kß lines (2.3 and 2.46 keV) in an energy-dispersive fluorescence spectrometer at the Swiss Light Source. Although further improvements in the segmentation and in the quantum efficiency at low energy are still necessary, this work paves the way for the development of single-photon-counting detectors in the soft X-ray energy range.

19.
Food Chem ; 288: 127-138, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30902272

RESUMEN

The effects of genotype, agro-climatic conditions (ACC), and cooking method as well as their interactions on the content of individual carotenoids and hydroxycinnamic acids in different potato tubers were evaluated. While zeaxanthin content was highly influenced by the ACC (up to 631-fold change), chlorogenic acid was similarly influenced by the cooking method (up to 3.1-fold increase after cooking), by the interactions ACC × cooking method (up to 2.1-fold increase) and genotype × cooking method (up to 1.7-fold increase). Stability/extractability of compounds after cooking was found to be genotype and ACC dependent, which suggest that genotype and ACC induces differential expression of genes for the biosynthesis pathways of carotenoids and hydroxycinnamic acids is different among, as well as components of the cellular matrix. These results are promising to apply in potato breeding programs with the perspective to develop new potato cultivars selected by their nutritional attributes.


Asunto(s)
Agricultura , Carotenoides/análisis , Clima , Culinaria , Ácidos Cumáricos/análisis , Diploidia , Genotipo , Tubérculos de la Planta/química , Solanum tuberosum/química , Cromatografía Líquida de Alta Presión , Genes de Plantas , Límite de Detección , Fenoles/análisis , Solanum tuberosum/genética , Espectrofotometría Ultravioleta
20.
Food Chem ; 281: 114-123, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30658737

RESUMEN

Crude extracts were prepared from residues of Rubus glaucus Benth by using food-grade solvents. Their efficacy protecting lipid oxidation of an oil in water (O/W) emulsion as well as of a bulk oil was tested. Stability of lipids during storage of an O/W emulsion was tested by the hydroperoxides and thiobarbituric acid reactive species (TBARS) measurements. Bulk oil stability was measured by the Rancimat method. Fruit pomace crude extracts were the best controlling lipid oxidation of an O/W emulsion, with crude extracts from overripe fruit and bush pruning residues acting as pro-oxidants as measured by the hydroperoxides levels. Neither of the crude extracts was able to inhibit lipid oxidation of the bulk oil. Mathematical modelling revealed that despite total phenolic content and partition coefficient of the crude extracts are important parameters to control lipid oxidation of an O/W emulsion, they do not totally explain their behavior in food-like systems.


Asunto(s)
Antioxidantes/análisis , Frutas/química , Rubus/química , Emulsiones , Análisis de los Alimentos , Metabolismo de los Lípidos , Modelos Teóricos , Extractos Vegetales/análisis , Sustancias Reactivas al Ácido Tiobarbitúrico
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