ABSTRACT
Tomato fruit is susceptible to chilling injury (CI) during its postharvest handling at low temperature. The symptoms caused by this physiological disorder have been commonly evaluated by visual inspection at a macro-observation scale on fruit surface; however, the structure at deeper scales is also affected by CI. This work aimed to propose a descriptive model of the CI development in tomato tissue under the micro-scale, micro-nano-scale and nano-scale approaches using fractal analysis. For that, quality and fractal parameters were determined. In this sense, light microscopy, Environmental Scanning Electron Microscopy (ESEM) and Atomic Force Microscopy (AFM) were applied to analyse micro-, micro-nano- and nano-scales, respectively. Results showed that the morphology of tomato tissue at the micro-scale level was properly described by the multifractal behaviour. Also, generalised fractal dimension (Dq=0) and texture fractal dimension (FD) of CI-damaged pericarp and cuticle were higher (1.659, 1.601 and 1.746, respectively) in comparison to non-chilled samples (1.606, 1.578 and 1.644, respectively); however, FD was unsuitable to detect morphological changes at the nano-scale. On the other hand, lacunarity represented an appropriate fractal parameter to detect CI symptoms at the nano-scale due to differences observed between damaged and regular ripe tissue (0.044 and 0.025, respectively). The proposed multi-scale approach could improve the understanding of CI as a complex disorder to the development of novel techniques to avoid this postharvest issue at different observation scales.
Subject(s)
Solanum lycopersicum , Fruit/chemistry , Cold TemperatureABSTRACT
Resumen En estudios previos se ha demostrado que la endotoxemia inducida por lipopolisacárido (LPS) produce un desacoplamiento cardiorrespiratorio (CRP) debido a los efectos fisiológicos de la inflamación sistémica. Adicionalmente se sabe que la oxitocina tiene efectos antiinflamatorios y propiedades cardioprotectoras; sin embargo, se desconoce si ésta modifica el acoplamiento CRP. El objetivo del presente estudio fue comparar diferentes métodos matemáticos lineales y no lineales para la detección del desacoplamiento cardiorrespiratorio entre series de tiempo cardiacas y respiratorias. Se estudiaron series de tiempo R-R obtenidas de electrocardiogramas de grupos de roedores macho a los cuales se les administró solución salina o vehículo (V); lipopolisacárido (LPS); oxitocina (O) y LPS + oxitocina (LPS+Ox). Las series R-R y respiratorias derivadas del electrocardiograma (EDR) se analizaron en conjunto para cuantificar su grado de acoplamiento a través de las técnicas de correlación cruzada; entropía muestral cruzada; entropía condicional; información mutua; e información mutua de Rényi para los cuatro grupos. Se observó que la oxitocina no parece favorecer el acoplamiento CRP durante la endotoxemia inducida por LPS. Finalmente, se encontró que la entropía muestral cruzada y la entropía condicional presentaron las mayores diferencias estadísticas para identificar el desacoplamiento CRP producido por el LPS.
Abstract Previous studies have shown that LPS-induced endotoxemia causes a cardiorespiratory (CRP) uncoupling owing to the physiological effects of systemic inflammation. Also, it is known that oxytocin has anti-inflammatory effects and cardioprotective properties; however, it is unknown whether it can modify the CRP coupling. This study aimed to compare different linear and nonlinear mathematics methods for the detection of cardiorespiratory uncoupling between cardiac and respiratory time series. The R-R time series of electrocardiograms of male rodents that were administered with saline solution (V); lipopolysaccharide (LPS); oxytocin (O) and LPS + oxytocin (LPS + Ox) were studied. We tested the R-R and respiratory series derived from the electrocardiogram (EDR) for the four groups to quantify the degree of coupling with cross-correlation; cross sample entropy; conditional entropy; mutual information; and Rényi's mutual information. We found that oxytocin does not seem to favor the CRP coupling during endotoxemia induced by LPS. Finally, we observed that the cross-sample entropy and the conditional entropy presented the highest statistical differences to identify the CRP uncoupling produced by LPS.
ABSTRACT
INTRODUCTION: The clinical use of magnetic resonance (MR) in patients with multiple sclerosis (MS) has advanced markedly over the past few years. Several groups around the world have developed consensus guidelines about the role of MR in MS at diagnosis and during follow up. However, in some regions is difficult to extrapolate the recommendations. AIM: To provide recommendations for the implementation of MR in MS patients at diagnosis and follow up in Venezuela. DEVELOPMENT: A group of experts from Venezuela that included neurologists and radiologists, by using the online surveys methodology as well as face to face meetings developed the intended consensus for the use of MR during the diagnosis and follow up of MS patients in Venezuela. Seventeen recommendations were established based on published evidence and the expert opinion. Recommendations focused on the role of conventional MR techniques and brain atrophy measurement in MS patients both at diagnosis and during follow-up. CONCLUSIONS: The recommendations of this consensus guidelines attempts to optimize the health care and management of patients with MS in Venezuela.
TITLE: Consenso venezolano para el uso de la resonancia magnetica en el diagnostico y seguimiento de pacientes con esclerosis multiple.Introduccion. El uso de la resonancia magnetica (RM) en el diagnostico y seguimiento de pacientes con esclerosis multiple (EM) se ha incrementado considerablemente durante los ultimos años. Diversos grupos de trabajo internacionales han intentado clarificar y normativizar el uso de la RM tanto en el momento del diagnostico como durante el seguimiento de los pacientes. Sin embargo, en muchas ocasiones se extrapolan datos de otras regiones que no contemplan la realidad de cada lugar o son dificiles de implementar. Objetivo. Elaborar un consenso venezolano para el uso de la RM en el diagnostico y seguimiento de pacientes con EM. Desarrollo. Un grupo de expertos de Venezuela, conformado por neurologos y radiologos, mediante metodologia de ronda de encuestas a distancia y reuniones presenciales, llevo adelante la elaboracion del consenso pretendido para el uso de la RM en el diagnostico y seguimiento de pacientes con EM en Venezuela. Se establecieron 17 recomendaciones basadas en la evidencia publicada y en el criterio de los expertos que participaron. Las recomendaciones se enfocaron en el papel de las tecnicas convencionales de RM, asi como en el de la medicion de la atrofia cerebral en pacientes con EM, tanto en el momento del diagnostico como durante el seguimiento. Conclusion. Las recomendaciones establecidas en el presente consenso permitiran optimizar el cuidado y el seguimiento de los pacientes con EM en Venezuela.
Subject(s)
Magnetic Resonance Imaging , Multiple Sclerosis/diagnostic imaging , Follow-Up Studies , Humans , Practice Guidelines as Topic , VenezuelaABSTRACT
The present study analyses the activity of 5'deiodinases type I and II in mammary gland during the breeding and estrous cycle of the rat, and includes indirect evidence that 5'D-I is present only in the alveolar epithelium. Data show that the mammary gland exhibits 5'D-II activity throughout the developmental period and its activity varies along the allometric growth of the gland. 5'D-I is detected during the differentiation stages of the alveolar epithelium (puberty, late pregnancy) and its activity rises significantly (10-fold) 24 h after delivery. Data also show that 5'D-I activity is not present in the fat pads of the gland. These findings suggest that during its differentiation and functional stages, the mammary gland requires an elevated and compartmentalized production of T3.
