162 research outputs found
Is arrhythmogenic right ventricular cardiomyopathy a paediatric problem too?
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heart muscle disease
that is often familial, characterized by arrhythmias of right ventricular origin, due to
transmural fatty or fibrofatty replacement of atrophic myocardium. ARVC is usually
diagnosed in the clinical setting between 20 and 40 years of age. The disease is
seldom recognised in infancy or under the age of 10, probably because the clinical
expression of the disease is normally postponed to youth and adulthood. This review
focuses its attention to the pediatric age, defined as the period of life raging from birth
to 18 years. During this span of life, ARVC is not so rare as previously supposed and
can be identified by applying the same diagnostic criteria proposed for the adult.
Ventricular arrhythmias range from isolated ventricular arrhythmias to sustained
ventricular tachycardia and fibrillation. Children and adolescents with ARVC must be
carefully evaluated and followed-up especially when a family positive history is
present, taking into account the high probability during this life-period that
asymptomatic affected patients become symptomatic or that arrhythmias worsen
during follow-up. The recent identification of the first defective gene opens new
avenues for the early identification of affected subjects even when asymptomatic.peer-reviewe
Nebivolol and its 4-keto derivative increase nitric oxide in endothelial cells by reducing its oxidative inactivation
AbstractObjectivesThe objective of the present study was to elucidate the vasodilator mechanisms of nebivolol, a high selective β1-receptor antagonist with antioxidant properties.BackgroundOxidative inactivation of nitric oxide (NO) is regarded as an important cause of its decreased biological activity.MethodsOxidative stress was induced through the binding of oxidized (ox)-low-density lipoprotein (LDL) to its specific endothelial receptor, called “lectin-like oxidized LDL receptor-1” (LOX-1), in bovine and human endothelial cells and in Chinese hamster ovary cells stably expressing bovine LOX-1 (BLOX-1-CHO cells). Reactive oxygen species (ROS), superoxide (O2·−), and NO were measured in cells by flow cytometry.ResultsNebivolol and its 4-keto derivative prevented in a dose-dependent manner the increase of ROS (p < 0.001) and O2·−(p < 0.001) in bovine aortic endothelial cells (BAECs), human umbilical vein endothelial cells (HUVECs), and BLOX-1-CHO cells stimulated with ox-LDL. Atenolol had no effect. The incubation of HUVECs and BAECs with ox-LDL reduced basal and bradykinin-induced NO and nitrite concentration (p from <0.001 to <0.01). Nebivolol and its 4-keto derivative prevented the reduction of basal and stimulated NO and nitrite concentration (p from <0.001 to <0.01) while atenolol had no effect. The preincubation of BAECs with blocking anti-LOX-1 monoclonal antibody (LOX-1 mAb) significantly counteracted the effect of ox-LDL on stimulated generation of NO (p < 0.001), but the effect was significantly lower than that of nebivolol and its 4-keto derivative alone (p < 0.01).ConclusionsIn conclusion, the findings of the present study indicate that nebivolol increases NO also by decreasing its oxidative inactivation
El Diseño Industrial como herramienta estratégica para el desarrollo de pequeñas empresas familiares
Cuando alguien se plantea iniciar una empresa, frecuentemente, el optimismo desmedido provoca altas esperanzas de triunfo inmediato, sin tener en cuenta todo lo que se necesita para crear un negocio. El emprendimiento ha incrementado su popularidad en los últimos años, gracias a casos de ensueño como Facebook. Sin embargo, en este mercado creciente, tener una buena idea ya no es suficiente. El mercado quiere la mejor solución para sí mismo y las empresas se encargan de solucionarles lo que requieren, pero no todas tienen la capacidad de solventar esas necesidades o muchas veces no saben cómo (sobre todo las MIPYME). El diseño industrial (poco explorado y desarrollado en la industria mexicana actualmente) puede ser un pilar importante para favorecer el éxito de las empresas nacientes, enfocándolo correctamente. Para muestra un botón, que a lo largo de este escrito se expone el caso de evolución y desarrollo de una PYME a través de esta disciplina
Online Interval Type-2 Fuzzy Extreme Learning Machine Applied to 3D Path Following for Remotely Operated Underwater Vehicles
In marine missions that involve 3D path following tasks, the overall goal of Underwater Vehicles (UVs) is the successful completion of a path previously specified by the operator. This implies that the path must be followed by the UV as closely as possible and arrive at a location for collection by a vessel. In this paper, an Online Interval Type-2 Fuzzy Extreme Learning Machine (OIT2-FELM) is suggested to achieve a robust following behaviour along a predefined 3D path using a Remotely Operated Underwater Vehicle (ROV). The proposed machine is a fast sequential learning scheme to the training of a more generalised model of TSK Interval Type-2 Fuzzy Inference Systems (TSK IT2 FISs) equivalent to Single Layer Feedforward Neural Networks (SLFNs). Learning new input data in the OIT2-FELM can be done one-by-one or chunk-by-chunk with a fixed or varying size. The OIT2-FELM is implemented in a hierarchical navigation strategy (HNS) as the main guidance mechanism to infer local control motions and to provide the ROV with the necessary autonomy to complete a predefined 3D path. For local path-planning, the OIT2-FELM performs signal classification for obstacle avoidance and target detection based on data collected by an on-board scan sonar. To evaluate the performance of the proposed OIT2-FELM, two different experiments are suggested. First, a number of benchmark problems in the field of non-linear system identification, regression and classification problems are used. Secondly, a number of experiments to the completion of a predefined 3D path using an ROV is implemented. Compared to other fuzzy strategies, the OIT2-FELM offered two significant capabilities. On the one hand, the OIT2-FELM provides a better treatment of uncertainty and noisy signals in underwater environments while improving the ROV's performance. Secondly, online learning in OIT2-FELM allows continuous knowledge discovery from survey data to infer the surroundings of the ROV. Experiment results to the completion of 3D paths show the effectiveness of the proposed approach to handle uncertainty and produce reasonable classification predictions (∼90.5% accuracy in testing data).</p
A Linear Criterion to sort Color Components in Images
The color and its representation play a basic role in Image Analysis process. Several methods can be beneficial whenever they have a correct representation of wave-length variations used to represent scenes with a camera. A wide variety of spaces and color representations is founded in specialized literature. Each one is useful in concrete circumstances and others may offer redundant color information (for instance, all RGB components are high correlated). This work deals with the task of identifying and sorting which component from several color representations offers the majority of information about the scene. This approach is based on analyzing linear dependences among each color component, by the implementation of a new sorting algorithm based on entropy. The proposal is tested in several outdoor/indoor scenes with different light conditions. Repeatability and stability are tested in order to guarantee its use in several image analysis applications. Finally, the results of this work have been used to enhance an external algorithm to compensate the camera random vibrations.El color y su representación juegan un papel fundamental en el proceso de análisis de imagen. Varios métodos pueden ser beneficiosos siempre que tengan una representación correcta de las variaciones de longitud de onda usadas para representar la escena. Una amplia variedad de espacios y representaciones de color se basa en la literatura especializada. Cada uno de ellos es útil en circunstancias concretas y puede ofrecer información de color redundante (por ejemplo, todos los componentes RGB están altamente correlacionados). En este trabajo se identifica y clasifica cuál componente ofrece la mayor cantidad de información acerca de la escena, a partir de varias representaciones de color. Este enfoque se basa en el análisis de las dependencias lineales entre cada canal y la implementación de un nuevo algoritmo para clasificar los componentes en base a la entropía. La propuesta se pone a prueba en varias escenas al aire libre y en interiores con diferentes condiciones de luz. La repetitividad y la estabilidad son probadas para garantizar su uso en aplicaciones de análisis de imágenes. Finalmente, los resultados de este trabajo son usados para mejorar un algoritmo externo para la compensación de vibraciones
Quality and reporting of clinical guidelines for breast cancer treatment: A systematic review
Background: High-quality, well-reported clinical practice guidelines (CPGs) and consensus statements
(CSs) underpinned by systematic reviews are needed. We appraised the quality and reporting of CPGs
and CSs for breast cancer (BC) treatment.
Methods: Following protocol registration (Prospero no: CRD42020164801), CPGs and CSs on BC treatment
were identified, without language restrictions, through a systematic search of bibliographic databases
(MEDLINE, EMBASE, Web of Science, Scopus, CDSR) and online sources (12 guideline databases
and 51 professional society websites) from January 2017 to June 2020. Data were extracted in duplicate
assessing overall quality using AGREE II (% of maximum score) and reporting compliance using RIGHT (%
of total 35 items); reviewer agreement was 98% and 96% respectively.
Results: There were 59 relevant guidance documents (43 CPGs, 16 CSs), of which 20 used systematic
reviews for evidence synthesis. The median overall quality was 54.0% (IQR 35.9e74.3) and the median
overall reporting compliance was 60.9% (IQR 44.5e84.4). The correlation between quality and reporting
was 0.9. Compared to CSs, CPGs had better quality (55.4% vs 44.2%; p ¼ 0.032) and reporting (67.18% vs
44.5%; p ¼ 0.005). Compared to subjective methods of evidence analysis, guidance documents that used
systematic reviews had better quality (76.3% vs 51.4%; p ¼ 0.001) and reporting (87.1% vs 59.4%;
p ¼ 0.001).
Conclusion: The quality and reporting of CPGs and CSs in BC treatment were moderately strong. Systematic
reviews should be used to improve the quality and reporting of CPGs and CSs.Beatriz Galindo (senor modality) Program by the Ministry of Science, Innovation, and Universities of the Spanish Governmen
The effects of hypoxia on zooplankton population estimates and migration in lakes
Many zooplankton species typically exhibit diel vertical migration (DVM), where
zooplankton migrate from the hypolimnion to the epilimnion of lakes at night.
Zooplankton exhibit this behavior to avoid visual predators and UV radiation by
remaining in the bottom waters during the day and ascending to the surface waters to feed
on phytoplankton at night. However, hypoxic conditions in the hypolimnion of lakes mayinterfere with DVM and force zooplankton to increase diel horizontal migration (DHM)
to find predation refuge in littoral zones. Climate change and eutrophication are expected
to increase the prevalence and severity of hypoxic conditions worldwide and thereby
possibly alter zooplankton migration patterns. We hypothesize that hypoxia will force
zooplankton to shift their migration patterns from predominantly DVM to DHM to avoid
oxygen-depleted bottom waters. To test our hypothesis, we are conducting a standardized
global sampling program to test whether pelagic, full water column estimates of
zooplankton are greater at night versus the day under hypolimnetic hypoxic versus oxic
conditions. Participants are aiming to sample at least one lake with an oxic hypolimnion
and one lake with a hypoxic hypolimnion during the thermally-stratified period at midday
and midnight. With our global dataset (currently expecting about 60 lakes in 22
countries), our goal is to improve our understanding of how global change may alter
zooplankton migration behavior and patterns in lakes.info:eu-repo/semantics/publishedVersio
Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions
OBJECTIVE:
Low-dose-rate brachytherapy (LDR-BT) in localized prostate cancer is available since 15 years in Italy. We realized the first national multicentre and multidisciplinary data collection to evaluate LDR-BT practice, given as monotherapy, and outcome in terms of biochemical failure.
METHODS:
Between May 1998 and December 2011, 2237 patients with early-stage prostate cancer from 11 Italian community and academic hospitals were treated with iodine-125 ((125)I) or palladium-103 LDR-BT as monotherapy and followed up for at least 2 years. (125)I seeds were implanted in 97.7% of the patients: the mean dose received by 90% of target volume was 145 Gy; the mean target volume receiving 100% of prescribed dose (V100) was 91.1%. Biochemical failure-free survival (BFFS), disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan-Meier method. Log-rank test and multivariable Cox regression were used to evaluate the relationship of covariates with outcomes.
RESULTS:
Median follow-up time was 65 months. 5- and 7-year DSS, OS and BFFS were 99 and 98%, 94 and 89%, and 92 and 88%, respectively. At multivariate analysis, the National Comprehensive Cancer Network score (p < 0.0001) and V100 (p = 0.09) were correlated with BFFS, with V100 effect significantly different between patients at low risk and those at intermediate/high risk (p = 0.04). Short follow-up and lack of toxicity data represent the main limitations for a global evaluation of LDR-BT.
CONCLUSION:
This first multicentre Italian report confirms LDR-BT as an excellent curative modality for low-/intermediate-risk prostate cancer.
ADVANCES IN KNOWLEDGE:
Multidisciplinary teams may help to select adequately patients to be treated with brachytherapy, with a direct impact on the implant quality and, possibly, on outcome
- …