Search results for "nucleus"
showing 10 items of 1803 documents
Herpes simplex virus 1 induces egress channels through marginalized host chromatin
2016
AbstractLytic infection with herpes simplex virus type 1 (HSV-1) induces profound modification of the cell nucleus including formation of a viral replication compartment and chromatin marginalization into the nuclear periphery. We used three-dimensional soft X-ray tomography, combined with cryogenic fluorescence, confocal and electron microscopy, to analyse the transformation of peripheral chromatin during HSV-1 infection. Our data showed an increased presence of low-density gaps in the marginalized chromatin at late infection. Advanced data analysis indicated the formation of virus-nucleocapsid-sized (or wider) channels extending through the compacted chromatin of the host. Importantly, co…
The Severity of Acute Stress Is Represented by Increased Synchronous Activity and Recruitment of Hypothalamic CRH Neurons
2016
The hypothalamo-pituitary-adrenocortical (HPA) axis regulates stress physiology and behavior. To achieve an optimally tuned adaptive response, it is critical that the magnitude of the stress response matches the severity of the threat. Corticotropin-releasing hormone (CRH) released from the paraventricular nucleus of the hypothalamus is a major regulator of the HPA axis. However, how CRH-producing neurons in an intact animal respond to different stressor intensities is currently not known. Using two-photon calcium imaging on intact larval zebrafish, we recorded the activity of CRH cells, while the larvae were exposed to stressors of varying intensity. By combining behavioral and physiologic…
Endocannabinoid LTD in Accumbal D1 Neurons Mediates Reward-Seeking Behavior
2020
Summary The nucleus accumbens (NAc) plays a key role in drug-related behavior and natural reward learning. Synaptic plasticity in dopamine D1 and D2 receptor medium spiny neurons (MSNs) of the NAc and the endogenous cannabinoid (eCB) system have been implicated in reward seeking. However, the precise molecular and physiological basis of reward-seeking behavior remains unknown. We found that the specific deletion of metabotropic glutamate receptor 5 (mGluR5) in D1-expressing MSNs (D1miRmGluR5 mice) abolishes eCB-mediated long-term depression (LTD) and prevents the expression of drug (cocaine and ethanol), natural reward (saccharin), and brain-stimulation-seeking behavior. In vivo enhancement…
Acetaldehyde as the first hit of addictive behaviour
2016
Unhealthy alcohol use is common in the Western society, which puts risk of health consequences, causing multiple behavioural injuries. Increasing evidence focuses on acetaldehyde, the first metabolite of ethanol, as the mediator of the several behavioural actions of alcohol, including its rewarding and motivational effects. In particular, acetaldehyde induces dopamine release in the nucleus accumbens modulating primary alcohol rewarding effect, drug seeking, and relapse behaviour. Recent behavioural studies point at acetaldehyde as a drug of abuse since its oral self-administration is induced and maintained in an operant/conflict paradigm. These findings provide further evidence on the role…
Embryo multinucleation at the two-cell stage is an independent predictor of intracytoplasmic sperm injection outcomes.
2016
Objective To determine the prognostic impact of the nuclear status at the two-cell stage on intracytoplasmic sperm injection (ICSI) outcomes. Design Retrospective study. Setting Hospital. Patient(s) Only ICSI cycles with time-lapse monitoring of transferred embryos with known implantation/delivery data from November 2012 to December 2014 were included. A total of 2,449 embryos were assessed for multinucleation rates at the two- and four-cell stage, and 608 transferred embryos were studied for ICSI outcomes. Intervention(s) None. Main Outcome Measure(s) Implantation rate (IR) and live birth rate (LBR) according to the number of multinucleated blastomeres at the two-cell stage: none (Without-…
Effect of high-frequency subthalamic neurostimulation on gait and freezing of gait in Parkinson's disease: a systematic review and meta-analysis.
2016
The aim of this meta-analysis was to summarize the short- and long-term effects of bilateral deep brain stimulation of the subthalamic nucleus (STN-DBS) on gait and freezing of gait (FOG) in Parkinson's disease and to detect predictors of post-stimulation outcome. A comprehensive review of the literature was conducted up to October 2015 using Medline Ovid databases for studies analyzing the effect of bilateral STN-DBS on FOG and/or gait. Sixteen studies with available data for the gait item (no. 29) of the Unified Parkinson's Disease Rating Scale (UPDRS) and six studies with the FOG item (no. 14) were included. Data were summarized for the following follow-up periods: 6-15, 24-48 and48 mont…
Glutamate and opioid antagonists modulate dopamine levels evoked by innately attractive male chemosignals in the nucleus accumbens of female rats
2017
Sexual chemosignals detected by vomeronasal and olfactory systems mediate intersexual attraction in rodents, and act as a natural reinforcer to them. The mesolimbic pathway processes natural rewards, and the nucleus accumbens receives olfactory information via glutamatergic projections from the amygdala. Thus, the aim of this study was to investigate the involvement of the mesolimbic pathway in the attraction toward sexual chemosignals. Our data show that female rats with no previous experience with males or their chemosignals display an innate preference for male-soiled bedding. Focal administration of the opioid antagonist b-funaltrexamine into the posterior ventral tegmental area does no…
Lateral Habenula 5-HT2C Receptor Function Is Altered by Acute and Chronic Nicotine Exposures
2021
Serotonin (5-HT) is important in some nicotine actions in the CNS. Among all the 5-HT receptors (5-HTRs), the 5-HT2CR has emerged as a promising drug target for smoking cessation. The 5-HT2CRs within the lateral habenula (LHb) may be crucial for nicotine addiction. Here we showed that after acute nicotine tartrate (2 mg/kg, i.p.) exposure, the 5-HT2CR agonist Ro 60-0175 (5–640 µg/kg, i.v.) increased the electrical activity of 42% of the LHb recorded neurons in vivo in rats. Conversely, after chronic nicotine treatment (6 mg/kg/day, i.p., for 14 days), Ro 60-0175 was incapable of affecting the LHb neuronal discharge. Moreover, acute nicotine exposure increased the 5-HT2CR-immunoreactive (IR)…
The sensory and nutritional experience of parents guide offsprings' feeding behavior
2016
Le comportement alimentaire est régulé par des facteurs physiologiques intrinsèques et est largement influencé par l’environnement culturel. Une prise alimentaire excessive et un mode de vie trop sédentaire sont les principales raisons de l’épidémie mondiale d’obésité. Si l’influence du contexte familial sur les habitudes alimentaires ne fait aucun doute, le fait que l’état nutritionnel, métabolique et hormonal des parents avant la conception, puis de la mère pendant la gestation et l’allaitement puisse influencer le comportement alimentaire futur de l’enfant est un concept novateur qui ouvre la voie à des mesures de prévention. Au cours des dernières décennies, des travaux sur des cohortes…
Viral highway to nucleus exposed by image correlation analyses.
2018
AbstractParvoviral genome translocation from the plasma membrane into the nucleus is a coordinated multistep process mediated by capsid proteins. We used fast confocal microscopy line scan imaging combined with image correlation methods including auto-, pair- and cross-correlation, and number and brightness analysis, to study the parvovirus entry pathway at the single-particle level in living cells. Our results show that the endosome-associated movement of virus particles fluctuates from fast to slow. Fast transit of single cytoplasmic capsids to the nuclear envelope is followed by slow movement of capsids and fast diffusion of capsid fragments in the nucleoplasm. The unique combination of …