Search results for "Biomedical"
showing 10 items of 2328 documents
Hydrodynamic IL10 Gene Transfer in Human Colon: Results from an "EX VIVO" Study with Potential Clinical Application in Crohn's Disease.
2017
Background: The aim of this work is to evaluate the efficacy of hydrodynamic venous IL10 gene delivery to "ex vivo" human colon segments and to determine its potential interest in Crohn's disease treatment. Methods: Twenty human colon segments were obtained from surgical resections. Hydrodynamic transfection through the main vein of the pedicle with 50 mL of hIL10 plasmid (20 mu g/mL) solution was performed on 13 of them. Tissue sections were cultured and DNA, RNA, and protein copies were determined after 1, 2, and 4 days. Data obtained were compared with 6 nontransfected specimens. Finally, 1 specimen was injected with gold nanoparticles, and their distribution was examined under electron …
Motor-skill learning in an insect inspired neuro-computational control system
2017
In nature, insects show impressive adaptation and learning capabilities. The proposed computational model takes inspiration from specific structures of the insect brain: after proposing key hypotheses on the direct involvement of the mushroom bodies (MBs) and on their neural organization, we developed a new architecture for motor learning to be applied in insect-like walking robots. The proposed model is a nonlinear control system based on spiking neurons. MBs are modeled as a nonlinear recurrent spiking neural network (SNN) with novel characteristics, able to memorize time evolutions of key parameters of the neural motor controller, so that existing motor primitives can be improved. The ad…
Electroporation by concentric-type needle electrodes and arrays.
2017
Abstract The efficacy of genomic medicine depends on gene transfer efficiency. In this area, electroporation has been found to be a highly promising method for physical gene transfer. However, electroporation raises issues related to electrical safety, tissue damage, and the number of required wounds. Concentric-type needle electrodes seek to address these issues by using a lower bias (10 V), a single wound, fewer processing steps, and a smaller working area (≈ 10 mm 3 ), thus offering greater accuracy and precision. Moreover, the needle can be arrayed to simultaneously treat several target regions. This paper proposes a novel method using concentric-type needle electrodes to improve the ef…
Analysis of Microstructure of the Cardiac Conduction System Based on Three-Dimensional Confocal Microscopy
2016
The specialised conducting tissues present in the ventricles are responsible for the fast distribution of the electrical impulse from the atrio-ventricular node to regions in the subendocardial myocardium. Characterisation of anatomical features of the specialised conducting tissues in the ventricles is highly challenging, in particular its most distal section, which is connected to the working myocardium via Purkinje-myocardial junctions. The goal of this work is to characterise the architecture of the distal section of the Purkinje network by differentiating Purkinje cells from surrounding tissue, performing a segmentation of Purkinje fibres at cellular scale, and mathematically describin…
Alkyne-Functionalized Coumarin Compound for Analytic and Preparative 4-Thiouridine Labeling
2017
Bioconjugation of RNA is a dynamic field recently reinvigorated by a surge in research on post-transcriptional modification. This work focuses on the bioconjugation of 4-thiouridine, a nucleoside that occurs as a post-transcriptional modification in bacterial RNA and is used as a metabolic label and for cross-linking purposes in eukaryotic RNA. A newly designed coumarin compound named 4-bromomethyl-7-propargyloxycoumarin (PBC) is introduced, which exhibits remarkable selectivity for 4-thiouridine. Bearing a terminal alkyne group, it is conductive to secondary bioconjugation via “click chemistry”, thereby offering a wide range of preparative and analytical options. We applied PBC to quantita…
Expanding the toolbox for Synechocystis sp. PCC 6803 : validation of replicative vectors and characterization of a novel set of promoters
2018
Cyanobacteria are promising ‘low-cost’ cell factories since they have minimal nutritional requirements, high metabolic plasticity and can use sunlight and CO2 as energy and carbon sources. The unicellular Synechocystis sp. PCC 6803, already considered the ‘green’ Escherichia coli, is the best studied cyanobacterium but to be used as an efficient and robust photoautotrophic chassis it requires a customized and well-characterized toolbox. In this context, we evaluated the possibility of using three self-replicative vectors from the Standard European Vector Architecture (SEVA) repository to transform Synechocystis. Our results demonstrated that the presence of the plasmid does not lead to an e…
Perspective: Essential study quality descriptors for data from nutritional epidemiologic research
2017
Pooled analysis of secondary data increases the power of research and enables scientific discovery in nutritional epidemiology. Information on study characteristics that determine data quality is needed to enable correct reuse and interpretation of data. This study aims to define essential quality characteristics for data from observational studies in nutrition. First, a literature review was performed to get an insight on existing instruments that assess the quality of cohort, case-control, and cross-sectional studies and dietary measurement. Second, 2 face-to-face workshops were organized to determine the study characteristics that affect data quality. Third, consensus on the data descrip…
Treg cells as potential cellular targets for functionalized nanoparticles in cancer therapy.
2016
Treg cell-mediated immune suppression appears to represent a significant barrier to effective anticancer immune responses and their inactivation or removal is viewed as a potential therapeutic approach. Although suitable tools for selective Treg cell manipulation in man are missing, their number and function can be altered by a number of drugs and biologicals and by reprogramming tumor-infiltrating antigen presenting cells. Nanoparticles offer exceptional new options in drug and gene delivery by prolonging the circulation time of their cargo, protecting it from degradation and promoting its local accumulation in cells and tissues. In tumor therapy, the use of nanoparticles is expected to o…
Translating nanoparticulate-personalized cancer vaccines into clinical applications: case study with RNA-lipoplexes for the treatment of melanoma
2016
The development of nucleic acid based vaccines against cancer has gained considerable momentum through the advancement of modern sequencing technologies and on novel RNA-based synthetic drug formats, which can be readily adapted following identification of every patient's tumor-specific mutations. Furthermore, affordable and individual ‘on demand’ production of molecularly optimized vaccines should allow their application in large groups of patients. This has resulted in the therapeutic concept of an active personalized cancer vaccine, which has been brought into clinical testing. Successful trials have been performed by intranodal administration of sterile isotonic solutions of synthetic …
Dental pulp stem cells for bone tissue engineering: a review of the current literature and a look to the future.
2018
The aim of this narrative review is to investigate the implication of mesenchymal stem cells harvested from human dental pulp in in vivo bone tissue regeneration. We focused on studies related to roles of human dental pulp stem cells in in vivo bone regeneration. A total of 1021 studies were identified; after the assessment of eligibility, only 39 studies were included in the review. The evaluated information of the studies regards the experimental strategies (e.g., the isolation method, the scaffold, the in vivo animal models). The overall main evidences highlighted from the analysis are that dental pulp stem cells and human-exfoliated deciduous teeth stem cells supported by a suitable sc…