Search results for "CELLULAR"

Advanced mechanotherapy: Biotensegrity  for governing metastatic tumor cell fate via modulating the extracellular matrix.

2021

Mechano-transduction is the procedure of mechanical stimulus translation via cells, among substrate shear flow, topography, and stiffness into a biochemical answer. TAZ and YAP are transcriptional coactivators which are recognized as relay proteins that promote mechano-transduction within the Hippo pathway. With regard to healthy cells in homeostasis, mechano-transduction regularly restricts proliferation, and TAZ and YAP are totally inactive. During cancer development a YAP/TAZ - stimulating positive response loop is formed between the growing tumor and the stiffening ECM. As tumor developments, local stromal and cancerous cells take advantage of mechanotransduction to enhance proliferatio…

Gelatin‐Hyaluronan Click‐Crosslinked Cryogels Elucidate Human Macrophage Invasion Behavior

2021

Multisite field potential recordings and analysis of the impulse propagation pattern in cardiac cells culture

2007

To provide further insights into the impulse propagation between cardiac myocytes, we performed multiparametric studies of excitation spread with cellular resolution in confluent monolayers of cultured cardiomyocytes (CM). Simultaneous paired intracellular recordings of action potentials in two individual CM revealed slight periodic spontaneous advances/delays in the interspike time lag. Multisite field potential recordings performed with microelectrode arrays (MEA) confirmed random and iterative cycle-to-cycle changes in the direction of excitation spread. These local spontaneous variations in the cardiac impulse propagation pathways may be a safety process protecting against microscopical…

Biomineralization toolkit: the importance of sample cleaning prior to the characterization of biomineral proteomes.

2013

In an interesting work published recently in PNAS, Drake et al. (1) presented a proteomic study of the skeleton from the stony coral Stylophora pistillata . This study identified proteins that are associated to the mineral phase (i.e., that potentially contribute to shape the skeleton). In other words, this set of proteins is supposed to represent the so-called “biomineralization toolkit.” Although some of the 36 proteins reported in Drake et al. (1) appear as genuine extracellular matrix (ECM) proteins related to biomineralization, such as coral acid-rich proteins or carbonic anhydrase, some others are obvious intracellular contaminants that should not be considered as skeletal organic mat…

Analysis of metabolic pathways by the growth of cells in the presence of organic solvents

1996

A new approach to the analysis of metabolic pathways involving poorly water-soluble intermediates is proposed. It relies upon the ability of the hydrophobic intermediates formed by a sequence of intracellular reactions to cross the membrane(s) and partition between aqueous and organic phases, when cells are incubated in the presence of a nonpolar and nontoxic organic solvent. As a result of this thermodynamically driven efflux of the formed intermediates from the cell, they accumulate in the organic medium in sufficient quantities for GC-MS analysis and identification. This enables direct determination of the sequence of chemical reactions involved with no requirement for the isolation of e…

Lewy body extracts from Parkinson disease brains trigger α-synuclein pathology and neurodegeneration in mice and monkeys

2014

Objective Mounting evidence suggests that α-synuclein, a major protein component of Lewy bodies (LB), may be responsible for initiating and spreading the pathological process in Parkinson disease (PD). Supporting this concept, intracerebral inoculation of synthetic recombinant α-synuclein fibrils can trigger α-synuclein pathology in mice. However, it remains uncertain whether the pathogenic effects of recombinant synthetic α-synuclein may apply to PD-linked pathological α-synuclein and occur in species closer to humans. Methods Nigral LB-enriched fractions containing pathological α-synuclein were purified from postmortem PD brains by sucrose gradient fractionation and subsequently inoculate…

Sural nerve biopsy studies in leigh's subacute necrotizing encephalomyelopathy

1986

Peripheral neuropathy marked by reduced nerve conduction velocities was found in four unrelated children, between the ages of 15 months and 9 years, whose autopsies revealed Leigh's subacute necrotizing encephalomyelopathy. Sural nerve biopsies disclosed primary demyelination and remyelination, as well as loss of myelinated and unmyelinated axons. The use of morphometric and electron microscopic studies shows that these techniques may reveal peripheral neuropathy in Leigh's disease more often than light microscopic methods alone.

SMAC mimetics promote NIK-dependent inhibition of CD4 + T H 17 cell differentiation

2019

Second mitochondria-derived activator of caspase (SMAC) mimetics (SMs) are selective antagonists of the inhibitor of apoptosis proteins (IAPs), which activate noncanonical NF-κB signaling and promote tumor cell death. Through gene expression analysis, we found that treatment of CD4+ T cells with SMs during T helper 17 (TH17) cell differentiation disrupted the balance between two antagonistic transcription factor modules. Moreover, proteomics analysis revealed that SMs altered the abundance of proteins associated with cell cycle, mitochondrial activity, and the balance between canonical and noncanonical NF-κB signaling. Whereas SMs inhibited interleukin-17 (IL-17) production and ameliorated …

Interactive effects of increased temperature and gadolinium pollution in Paracentrotus lividus sea urchin embryos: a climate change perspective

2021

Gradual ocean warming and marine heatwaves represent major threats for marine organisms already facing other anthropogenic-derived hazards, such as chemical contamination in coastal areas. In this study, the combined effects of thermal stress and exposure to gadolinium (Gd), a metal used as a contrasting agent in medical imaging which enters the aquatic environment, were investigated in the embryos and larvae of the sea urchin Paracentrotus lividus. Embryos were exposed to six treatments of three temperatures (18 °C, 21 °C, 24 °C) and two Gd concentrations (control: 0 μM; treated: 20 μM). With respect to developmental progression, increased temperature accelerated development and achievemen…

Disarrangement of Endoplasmic reticulum-mitochondria communication impairs Ca2+ homeostasis in FRDA

2020

AbstractFriedreich ataxia (FRDA) is a neurodegenerative disorder characterized by neuromuscular and neurological manifestations. It is caused by mutations in gene FXN, which results in loss of the mitochondrial protein frataxin. Endoplasmic Reticulum-mitochondria associated membranes (MAMs) are inter-organelle structures involved in the regulation of essential cellular processes, including lipid metabolism and calcium signaling. In the present study, we have analyzed in both, unicellular and multicellular models of FRDA, an analysis of calcium management and of integrity of MAMs. We observed that function of MAMs is compromised in our cellular model of FRDA, which was improved upon treatmen…