Search results for "Time-lapse"

JNK ‐dependent gene regulatory circuitry governs mesenchymal fate

2015

The epithelial to mesenchymal transition (EMT) is a biological process in which cells lose cell-cell contacts and become motile. EMT is used during development, for example, in triggering neural crest migration, and in cancer metastasis. Despite progress, the dynamics of JNK signaling, its role in genomewide transcriptional reprogramming, and involved downstream effectors during EMT remain largely unknown. Here, we show that JNK is not required for initiation, but progression of phenotypic changes associated with EMT. Such dependency resulted from JNK-driven transcriptional reprogramming of critical EMT genes and involved changes in their chromatin state. Furthermore, we identified eight no…

Dimerization of the kinase ARAF promotes MAPK pathway activation and cell migration.

2014

The RAF family of kinases mediates RAS signaling, and RAF inhibitors can be effective for treating tumors with BRAF V600E mutant protein. However, RAF inhibitors paradoxically accelerate metastasis in RAS -mutant tumors and become ineffective in BRAF V600E tumors because of reactivation of downstream mitogen-activated protein kinase (MAPK) signaling. We found that the RAF isoform ARAF has an obligatory role in promoting MAPK activity and cell migration in a cell type–dependent manner. Knocking down ARAF prevented the activation of MAPK kinase 1 (MEK1) and extracellular signal–regulated kinase 1 and 2 (ERK1/2) and decreased the number of protrusions from tumor cell spheroids in three-dimensi…

Full in vitro fertilization laboratory mechanization: toward robotic assisted reproduction?

2011

Objective To describe the current efforts made to standardize different steps of assisted reproductive technology processes by the introduction of new technologies for the nonsubjective sperm selection process, oocyte denudation by mechanical removal of cumulus cells, oocyte positioning, sperm motility screening, fertilization, embryo culture, media replacement by microfluidics, and monitoring of embryo development by time-lapse photography, embryo secretions, and/or O 2 consumption. These technologies could be integrated in a unique and fully automated device. Design Pubmed database and research and development data from authors. Setting University-affiliated private center. Patient(s) Non…

The type of GnRH analogue used during controlled ovarian stimulation influences early embryo developmental kinetics: a time-lapse study

2013

OBJECTIVE: To explore if the GnRH analogue used for controlled ovarian stimulation (COS) and the ovulation triggering factor (GnRH agonist + hCG triggering versus GnRH antagonist + GnRH agonist triggering) affect embryo development and kinetics.STUDY DESIGN: In a retrospective cohort study in the Instituto Valenciano de Infertilidad (IVI) Alicante and the Instituto Universitario-IVI Valencia, Spain, 2817 embryos deriving from 400 couples undergoing oocyte donation were analysed. After controlled ovarian stimulation and IVF/intracytoplamic sperm injection, the timing of embryonic cleavages was assessed by a video time-lapse system. The results were analysed using Student's t test for compari…

The human first cell cycle: impact on implantation.

2013

The morphology of fertilization events has been related to successful implantation by subjective criteria (pronuclei score, pronuclei symmetry and position). This work first described these events by time-lapse technology and then compared the timings of fertilization events (second polar body extrusion, first and second pronuclei appearance, abuttal and fading) in implanted versus nonimplanted embryos in a 2-year cohort retrospective study. A total of 1448 transferred embryos from 842 patients undergoing intracytoplasmic sperm injection with oocyte donation were monitored, 212 embryos from treatments where the number of gestational sacs matched the number of transferred embryos and 687 emb…

Reelin and CXCL12 regulate distinct migratory behaviors during the development of the dopaminergic system.

2014

The proper functioning of the dopaminergic system requires the coordinated formation of projections extending from dopaminergic neurons in the substantia nigra (SN), ventral tegmental area (VTA) and retrorubral field to a wide array of forebrain targets including the striatum, nucleus accumbens and prefrontal cortex. The mechanisms controlling the assembly of these distinct dopaminergic cell clusters are not well understood. Here, we have investigated in detail the migratory behavior of dopaminergic neurons giving rise to either the SN or the medial VTA using genetic inducible fate mapping, ultramicroscopy, time-lapse imaging, slice culture and analysis of mouse mutants. We demonstrate that…

DNA DEMETHYLATION CAUSED BY 5-AZA-2’-DEOXYCYTIDINE TREATMENT AFFECTS GENOME STABILITY BY INDUCING MITOTIC ALTERATIONS AND ANEUPLOIDY IN HCT-116 TUMOR…

2014

Le tecniche geofisiche per lo studio degli acquiferi costieri soggetti ad intrusione marina: l’acquifero di Petrosino (TP)

2011

Un’indagine geofisica è stata condotta nella zona costiera di Petrosino, situata in Sicilia Sud-Occidentale tra i paesi di Marsala e di Mazara del Vallo, per uno studio dell’evoluzione temporale del fenomeno dell’intrusione di acqua marina nella falda costiera, accentuato presumibilmente dalle attività antropiche. L’eccessivo sfruttamento della falda acquifera dovuto a un intensivo uso agricolo ha modificato significativamente il naturale assetto idro-geochimico del bacino, accentuando il fenomeno intrusivo già di per sé critico nella zona. Lo studio è stato basato sull’elaborazione integrata di dati idrogeologici, geochimici e geofisici (sondaggi elettromagnetici TDEM), disponibili grazie …

Studi di base per il monitoraggio elettrotomografico dell’intrusione salina dell’acquifero di Petrosino

2009

Time-Lapse Dynamics of the Mouse Oocyte Chromatin Organisation during Meiotic Resumption

2014

In the mammalian oocyte, distinct patterns of centromeres and pericentromeric heterochromatin localisation correlate with the gamete’s developmental competence. Mouse antral oocytes display two main types of chromatin organisation: SN oocytes, with a ring of Hoechst-positive chromatin surrounding the nucleolus, and NSN oocytes lacking this ring. When matured to MII and fertilised, only SN oocytes develop beyond the 2-cell, and reach full term. To give detailed information on the dynamics of the SN or NSN chromatin during meiosis resumption, we performed a 9 hr time-lapse observation. The main significant differences recorded are: (1) reduction of the nuclear area only in SN oocytes; (2) ~17…