144 research outputs found
HOLMeS: eHealth in the Big Data and Deep Learning Era
Now, data collection and analysis are becoming more and more important in a variety of application domains, as long as novel technologies advance. At the same time, we are experiencing a growing need for humanâmachine interaction with expert systems, pushing research toward new knowledge representation models and interaction paradigms. In particular, in the last few years, eHealthâwhich usually indicates all the healthcare practices supported by electronic elaboration and remote communicationsâcalls for the availability of a smart environment and big computational resources able to offer more and more advanced analytics and new humanâcomputer interaction paradigms. The aim of this paper is to introduce the HOLMeS (health online medical suggestions) system: A particular big data platform aiming at supporting several eHealth applications. As its main novelty/functionality, HOLMeS exploits a machine learning algorithm, deployed on a cluster-computing environment, in order to provide medical suggestions via both chat-bot and web-app modules, especially for prevention aims. The chat-bot, opportunely trained by leveraging a deep learning approach, helps to overcome the limitations of a cold interaction between users and software, exhibiting a more human-like behavior. The obtained results demonstrate the effectiveness of the machine learning algorithms, showing an area under ROC (receiver operating characteristic) curve (AUC) of 74.65% when some first-level features are used to assess the occurrence of different chronic diseases within specific prevention pathways. When disease-specific features are added, HOLMeS shows an AUC of 86.78%, achieving a greater effectiveness in supporting clinical decisions
Passivity and Maximum Quality Factor Assessment in Lossy 2-port Transfer Functions
International audienceLossy transfer functions are appealing in the design of filters and electric networks, as they can be exactly implemented by physical passive components. However, lossy techniques relax most of the constraints governing the design and thus offer many degrees of freedom but with unclear effects on realizability. This work describes first an analytical method to check whether a given 2-port matrix transfer function is passive. Moreover, for comparison purposes, a technique to assess the maximum allowed predistortion is proposed, related to the highest required quality factor
A mm-Wave 2D Ultra-Wideband Imaging Radar for Breast Cancer Detection
This paper presents the preliminary design of a mm-wave ultra-wideband (UWB) radar for breast cancer detection. A mass screening of women for breast cancer is essential, as the early diagnosis of the tumour allows best treatment outcomes. A mm-wave UWB radar could be an innovative solution to achieve the high imaging resolution required without risks for the patient. The 20â40âGHz frequency band used in the system proposed in this work guarantees high cross/range resolution performances. The developed preliminary architecture employs two monomodal truncated double-ridge waveguides that act as antennas; these radiators are shifted by microstep actuators to form a synthetic linear aperture. The minimum antenna-to-antenna distance achievable, the width of the synthetic aperture, and the minimum frequency step determine the performance of the 2D imaging system. Measures are performed with a mm-wave vector network analyzer driven by an automatic routine, which controls also the antennas shifts. The scattering matrix is then calibrated and the delay-multiply-and-sum (DMAS) algorithm is applied to elaborate a high-resolution 2D image of the targets. Experimental results show that 3âmm cross and 8âmm range resolutions were achieved, which is in line with theoretical expectations and promising for future developments
Editorial: Exploring system justification phenomenon among disadvantaged individuals
The question of why (or even when) the disadvantaged might be more or less supportive of existing social arrangements is a matter of debate amongst social and political psychologists (e.g., Passini, 2019; Jost, 2020, see also Rubin et al., 2022). Accordingly, for this Research Topic, we chose a title that was deliberately broad in scope, accommodating several aspects that included: (a) the drivers of system justification; (b) the socio-structural conditions that enhance or dampen system justification, (c) the ideological correlates of system support, and (d) the impact of system justification on wellbeing. Taken together, the contributions comprised in this Research Topic provide a comprehensive analysis of these four issue
Tympanic Membrane Collagen Expression by Dynamically Cultured Human Mesenchymal Stromal Cell/Star-Branched Poly(Δ-Caprolactone) Nonwoven Constructs
The tympanic membrane (TM) primes the sound transmission mechanism due to special
ïŹbrous layers mainly of collagens II, III, and IV as a product of TM ïŹbroblasts, while type I is less
represented. In this study, human mesenchymal stromal cells (hMSCs) were cultured on star-branched
poly("-caprolactone) (*PCL)-based nonwovens using a TM bioreactor and proper dierentiating
factors to induce the expression of the TM collagen types. The cell cultures were carried out for
one week under static and dynamic conditions. Reverse transcriptase-polymerase chain reaction
(RT-PCR) and immunohistochemistry (IHC) were used to assess collagen expression. A Finite
Element Model was applied to calculate the stress distribution on the scaolds under dynamic
culture. Nanohydroxyapatite (HA) was used as a ïŹller to change density and tensile strength of *PCL
scaolds. In dynamically cultured *PCL constructs, ïŹbroblast surface marker was overexpressed, and
collagen type II was revealed via IHC. Collagen types I, III and IV were also detected. Von Mises
stress maps showed that during the bioreactor motion, the maximum stress in *PCL was double
that in HA/*PCL scaolds. By using a *PCL nonwoven scaold, with suitable physico-mechanical
properties, an oscillatory culture, and proper dierentiative factors, hMSCs were committed into
ïŹbroblast lineage-producing TM-like collagens
Growing bone tissue-engineered niches with graded osteogenicity: an in vitro method for biomimetic construct assembly
The traditional bone tissue-engineering approach exploits mesenchymal stem cells ( MSCs) to be seeded once only on three-dimensional (3D) scaffolds, hence, differentiated for a certain period of time and resulting in a homogeneous osteoblast population at the endpoint. However, after achieving terminal osteodifferentiation, cell viability is usually markedly compromised. On the other hand, naturally occurring osteogenesis results from the coexistence of MSC progenies at distinct differentiative stages in the same microenvironment. This diversiïŹcation also enables long-term viability of the mature tissue. We report an easy and tunable in vitro method to engineer simple osteogenic cell niches in a biomimetic fashion. The niches were grown via periodic reseeding of undifferentiated MSCs on MSC/scaffold constructs, the latter undergoing osteogenic commitment. Timefractioning of the seeded cell number during differentiation time of the constructs allowed graded osteogenic cell populations to be grown together on the same scaffolds (i.e., not only terminally differentiated osteoblasts). In such cell-dynamic systems, the overall differentiative stage of the constructs could also be tuned by varying the cell density seeded at each inoculation. In this way, we generated two different biomimetic niche models able to host good reservoirs of preosteoblasts and other osteoprogenitors after 21 culture days. At that time, the niche type resulting in 40.8% of immature osteogenic progenies and only 59.2% of mature osteoblasts showed a calcium content comparable to the constructs obtained with the traditional culture method (i.e., 100.03 â 29.30 vs. 78.51 â 28.50 pg/cell, respectively; p = not signiïŹcant), the latter colonized only by fully differentiated osteoblasts showing exhausted viability. This assembly method for tissue-engineered constructs enabled a set of important parameters, such as viability, colonization, and osteogenic yield of the MSCs to be balanced on 3D scaffolds, thus achieving biomimetic in vitro models with graded osteogenicity, which are more complex and reliable than those currently used by tissue engineers
In vitro study on the generation of tympanic membrane substitutes via tissue engineering
The tympanic membrane (TM) is an anatomical structure with unique histological and physiological features playing a fundamental role in sound transmission. In particular, the middle layer of the pars tensa, which represents the widest and thickest surface portion of the TM, consists of connective tissue mainly composed of collagen types II and III fibers, while collagen type I is present at a lesser extent [1]. Several pathologies affect the TM, including otitis media, tympanosclerosis, cholesteatoma and perforation that require reconstructive surgery depending on the lesion extent [2]. To this purpose, the temporalis fascia is currently considered as the gold standard material. However, due to limited graft availability, fully synthetic substitutes are also applied, with poorly satisfactory outcomes. For these reasons new strategies for TM replacement are still needed. In this study, we employed a tissue engineering (TE) approach for the regeneration of TM substitutes selecting some biocompatible and bioresorbable polymeric matrices to be cultured with human bone marrow-derived mesenchymal stem cells (MSCs). We set up a cell differentiation protocol using an appropriate mix of growing factors to obtain the in vitro differentiation of MSCs into TM fibroblasts. Furthermore, because of the role played by mechanical forces in TM motion, these engineered substitutes underwent mechanical stress during the culture. The obtained biohybrid constructs were characterized about cellular viability assays, gene expression quantification as well as histochemical and immunohistochemical analyses. Moreover, native TMs from cadavers were investigated for assessment and optimization of the engineered constructs. Our results showed that MSCs were able to grow and differentiate properly on the selected biomaterials and to synthesize appropriate extracellular matrix molecules. Moreover, the applied mechanical forces seem to promote TM-fibroblastic differentiation, increasing the production of collagen type II, that is a peculiarity of TM structure
Nutritional status and quality of life in adults undergoing allogeneic hematopoietic stem cell transplantation
Although the effects of malnutrition on morbidity and mortality in adult patients undergoing allogeneic hematopoietic stem cell transplantation are clear, the relationship with quality of life (QOL) is less clear. The purpose of this study was to assess the relationship between malnutrition and QOL. A prospective observational study was conducted in 36 adult patients undergoing allogeneic hematopoietic stem cell transplantation. Adapted criteria of the Global Leadership Initiative on malnutrition have been used for the diagnosis of malnutrition in clinical settings. A cancer linear analog scale was used to assess QOL. Overall QOL at 14 days after allogeneic hematopoietic stem cell transplantation was 37.1 (95% CI 2.9â45.39) in patients without severe malnutrition, versus 16.0 (95% CI â 6.6 to 38.6) in patients with severe malnutrition (p = 0.05). At discharge, it was 48.0 (95% CI 38.4â57.6) versus 34.0 (95% CI 4.1â63.9) (p = 0.27). The results of our study suggest that patients with severe malnutrition at discharge tend to have worse QOL. A larger cohort of patients is required to confirm this hypothesis
Interfacing polymeric scaffolds with primary pancreatic ductal adenocarcinoma cells to develop 3D cancer models.
Abstract We analyzed the interactions between primary cells from pancreatic ductal adenocarcinoma (PDAC) and polymeric scaffolds to develop 3D cancer models useful for mimicking the biology of this tumor. Three scaffold types based on two biocompatible polymeric formulations, such as poly(vinyl alcohol)/gelatin (PVA/G) mixture and poly(ethylene oxide terephthalate)/poly(butylene terephthalate) (PEOT/PBT) copolymer, were obtained via different techniques, namely, emulsion and freeze-drying, compression molding followed by salt leaching, and electrospinning. In this way, primary PDAC cells interfaced with different pore topographies, such as sponge-like pores of different shape and size or nanofiber interspaces. The aim of this study was to investigate the influence played by the scaffold architecture over cancerous cell growth and function. In all scaffolds, primary PDAC cells showed good viability and synthesized tumor-specific metalloproteinases (MMPs) such as MMP-2, and MMP-9. However, only sponge-like pores, obtained via emulsion-based and salt leaching-based techniques allowed for an organized cellular aggregation very similar to the native PDAC morphological structure. Differently, these cell clusters were not observed on PEOT/PBT electrospun scaffolds. MMP-2 and MMP-9, as active enzymes, resulted to be increased in PVA/G and PEOT/PBT sponges, respectively. These findings suggested that spongy scaffolds supported the generation of pancreatic tumor models with enhanced aggressiveness. In conclusion, primary PDAC cells showed diverse behaviors while interacting with different scaffold types that can be potentially exploited to create stage-specific pancreatic cancer models likely to provide new knowledge on the modulation and drug susceptibility of MMPs
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