Search results for "mot"

Collective behavior of quorum-sensing run-and-tumble particles in confinement

2016

We study a generic model for quorum-sensing bacteria in circular confinement. Every bacterium produces signaling molecules, the local concentration of which triggers a response when a certain threshold is reached. If this response lowers the motility then an aggregation of bacteria occurs, which differs fundamentally from standard motility-induced phase separation due to the long-ranged nature of the concentration of signal molecules. We analyze this phenomenon analytically and by numerical simulations employing two different protocols leading to stationary cluster and ring morphologies, respectively.

Stem cell functionality is microenvironmentally defined during tumour expansion and therapy response in colon cancer

2018

Solid malignancies have been speculated to depend on cancer stem cells (CSCs) for expansion and relapse after therapy. Here we report on quantitative analyses of lineage tracing data from primary colon cancer xenograft tissue to assess CSC functionality in a human solid malignancy. The temporally obtained clone size distribution data support a model in which stem cell function in established cancers is not intrinsically, but is entirely spatiotemporally orchestrated. Functional stem cells that drive tumour expansion predominantly reside at the tumour edge, close to cancer-associated fibroblasts. Hence, stem cell properties change in time depending on the cell location. Furthermore, although…

Cancer combination therapy of the sesquiterpenoid artesunate and the selective EGFR-tyrosine kinase inhibitor erlotinib.

2017

Abstract Background The shift from cytotoxic to targeted chemotherapy led to improved treatment outcomes in oncology. Nevertheless, many cancer patients cannot be cured from their disease because of the development of drug resistance and side effects. Purpose There is an ongoing quest for novel compounds, which raised not only the interest in natural products but also in novel combination therapy regimens. Study design In this review, we report on the inhibition epidermal growth factor receptor (EGFR) by targeted small molecules and their combination with natural products from medicinal plants. Results The combination of erlotinib with artesunate leads to synergistic inhibition of cell grow…

Recent discoveries of anticancer flavonoids.

2017

Abstract In this review we report the recent advances in anticancer activity of the family of natural occurring flavonoids, covering the time span of the last five years. The bibliographic data will be grouped, on the basis of biological information, in two great categories: reports in which the extract plants bioactivity is reported and the identification of each flavonoid is present or not, and reports in which the anticancer activity is attributable to purified and identified flavonoids from plants. Wherever possible, the targets and mechanisms of action as well as the structure-activity relationships of the molecules will be reported. Also, in the review it was thoroughly investigated t…

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…

The Drosophila Larval Locomotor Circuit Provides a Model to Understand Neural Circuit Development and Function

2021

It is difficult to answer important questions in neuroscience, such as: “how do neural circuits generate behaviour?,” because research is limited by the complexity and inaccessibility of the mammalian nervous system. Invertebrate model organisms offer simpler networks that are easier to manipulate. As a result, much of what we know about the development of neural circuits is derived from work in crustaceans, nematode worms and arguably most of all, the fruit fly, Drosophila melanogaster. This review aims to demonstrate the utility of the Drosophila larval locomotor network as a model circuit, to those who do not usually use the fly in their work. This utility is explored first by discussion…

2017

Functional near infrared spectroscopy (fNIRS) is a promising neuroimaging method for investigating networks of cortical regions over time. We propose a directed effective connectivity method (TPDC) allowing the capture of both time and frequency evolution of the brain’s networks using fNIRS data acquired from healthy subjects performing a continuous finger-tapping task. Using this method we show the directed connectivity patterns among cortical motor regions involved in the task and their significant variations in the strength of information flow exchanges. Intra and inter-hemispheric connections during the motor task with their temporal evolution are also provided. Characterisation of the …

Quantitatively characterizing drug-induced arrhythmic contractile motions of human stem cell-derived cardiomyocytes.

2018

Quantification of abnormal contractile motions of cardiac tissue has been a noteworthy challenge and significant limitation in assessing and classifying the drug-induced arrhythmias (i.e. Torsades de pointes). To overcome these challenges, researchers have taken advantage of computational image processing tools to measure contractile motion from cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs). However, the amplitude and frequency analysis of contractile motion waveforms doesn't produce sufficient information to objectively classify the degree of variations between two or more sets of cardiac contractile motions. In this paper, we generated contractile motion dat…

Dynamic large-scale network synchronization from perception to action

2018

Sensory-guided actions entail the processing of sensory information, generation of perceptual decisions, and the generation of appropriate actions. Neuronal activity underlying these processes is distributed into sensory, fronto-parietal, and motor brain areas, respectively. How the neuronal processing is coordinated across these brain areas to support functions from perception to action remains unknown. We investigated whether phase synchronization in large-scale networks coordinate these processes. We recorded human cortical activity with magnetoencephalography (MEG) during a task in which weak somatosensory stimuli remained unperceived or were perceived. We then assessed dynamic evolutio…

Consensus paper on the “executive summary of the international conference on Mediterranean diet and health: a lifelong approach” an Italian initiativ…

2018

The Mediterranean Diet Foundation, in collaboration with the International Menarini Foundation, organized the “International Conference on Mediterranean Diet and Health: A Lifelong Approach.” The Conference was held in Ostuni (Puglia, Italy) from March 30 to April 1, 2017. The event received the endorsement of the American Federation for Aging Research, the Research Consortium “Luigi Amaducci,” the European Nutrition for Health Alliance, the European Union Geriatric Medicine Society, the Clinical Section of the International Association of Gerontology and Geriatrics—European Region, the National Research Council Research Project on Aging, the Italian Society of Gerontology and Geriatrics, a…