SUMMARY Transient increases in nucleus accumbens (NAc) dopamine concentration are observed when animals are presented with motivationally salient stimuli and are theorized to energize reward seeking. They arise from high frequency firing of dopamine neurons in the ventral tegmental area (VTA), which also results in the release of endocannabinoids from dopamine cell bodies. In this context, endocannabinoids are thought to regulate reward seeking by modulating dopamine signaling, although a direct link has never been demonstrated. To test this, we pharmacologically manipulated endocannabinoid neurotransmission in the VTA while measuring transient changes in dopamine concentration in the NAc during reward seeking. Disrupting endocannabinoid signaling dramatically reduced, whereas augmenting levels of the endocannabinoid 2-arachidonoylglycerol (2AG) increased, cue-evoked dopamine concentrations and reward seeking. These data suggest that 2AG in the VTA regulates reward seeking by sculpting ethologically relevant patterns of dopamine release during reward-directed behavior.
A critical step toward understanding autism spectrum disorder (ASD) is to identify both genetic and environmental risk factors. A number of rare copy number variants (CNVs) have emerged as robust genetic risk factors for ASD, but not all CNV carriers exhibit ASD and the severity of ASD symptoms varies among CNV carriers. Although evidence exists that various environmental factors modulate symptomatic severity, the precise mechanisms by which these factors determine the ultimate severity of ASD are still poorly understood. Here, using a mouse heterozygous for Tbx1 (a gene encoded in 22q11.2 CNV), we demonstrate that a genetically-triggered neonatal phenotype in vocalization generates a negative environmental loop in pup-mother social communication. Wild-type pups used individually diverse sequences of simple and complicated call types, but heterozygous pups used individually invariable call sequences with less complicated call types. When played back, representative wild-type call sequences elicited maternal approach, but heterozygous call sequences were ineffective. When the representative wild-type call sequences were randomized, they were ineffective in eliciting vigorous maternal approach behavior. These data demonstrate that an ASD risk gene alters the neonatal call sequence of its carriers and this pup phenotype in turn diminishes maternal care through atypical social communication. Thus, an ASD risk gene induces, through atypical neonatal call sequences, less than optimal maternal care as a negative neonatal environmental factor.
Context For children with growth hormone deficiency (GHD), treatment burden with daily somatropin injections (hGH) is high, which may lead to poor adherence and suboptimal overall treatment outcomes. Lonapegsomatropin (TransCon hGH) is an investigational long-acting, once-weekly prodrug for the treatment of GHD. Objective The objective of this study was to evaluate the efficacy and safety of once-weekly lonapegsomatropin vs daily somatropin. Design The heiGHt Trial was a randomized, open-label, active-controlled, 52-week phase 3 trial (NCT02781727). Setting This trial took place at 73 sites across 15 countries. Patients This trial enrolled and dosed 161 treatment-naïve, prepubertal patients with GHD. Interventions Patients were randomized 2:1 to receive lonapegsomatropin 0.24 mg hGH/kg/wk or an equivalent weekly dose of somatropin, delivered daily. Main Outcome Measure The primary end point was annualized height velocity (AHV) at Week 52. Secondary efficacy end points included change from baseline in height standard deviation scores (SDS). Results Least squares (LS) mean (SE) AHV at 52 weeks was 11.2 (0.2) cm/year for lonapegsomatropin vs. 10.3 (0.3) cm/year for daily somatropin (P=0.009), with lonapegsomatropin demonstrating both non-inferiority and superiority over daily somatropin. LS mean (SE) height SDS increased from baseline to Week 52 by 1.10 (0.04) vs. 0.96 (0.05) in the weekly lonapegsomatropin vs. daily somatropin groups (P=0.01). Bone age/chronological age ratio, adverse events, tolerability, and immunogenicity were similar between groups. Conclusions The trial met its primary objective of non-inferiority in AHV and further showed superiority of lonapegsomatropin compared to daily somatropin, with similar safety, in treatment-naïve children with GHD.
To compare the efficacy, safety, and tolerability of waterfree cyclosporine formulation (CyclASol) at 2 concentrations (0.1% and 0.05% of cyclosporine [CsA]) to vehicle when applied twice daily for 16 weeks in patients with dry eye disease (DED). An open-label Restasis (Allergan, Irvine, CA) arm was included to allow a direct comparison with an approved therapy.Design: An exploratory phase II, multicenter, randomized, vehicle-controlled clinical trial, double-masked between CyclASol and vehicle with an open-label comparator.Participants: Two hundred and seven eligible patients with a history of dry eye disease were randomized 1:1:1:1 to 1 of 4 treatment arms (CyclASol 0.05%, n ¼ 51; CyclASol 0.1%, n ¼ 51; vehicle, n ¼ 52, and Restasis, n ¼ 53).Methods: After a 2-week run-in period with twice-daily dosing of Systane Balance (Alcon, Fort Worth, TX), patients were randomized to the respective treatment arm and dosed twice daily for 16 weeks.Main Outcome Measures: The study was set up to explore efficacy on a number of sign and symptom end points including total and subregion corneal fluorescein staining, conjunctival staining, visual analog scale (VAS) for dry eye symptoms VAS severity, and Ocular Surface Disease Index (OSDI) questionnaire.Results: CyclASol showed a consistent reduction in corneal and conjunctival staining compared with both vehicle and Restasis over the 16-week treatment period, with an early onset of effect (at day 14). A mixed-effects modelebased approach demonstrated that the CyclASol drug effect was statistically significant over vehicle (total corneal staining P < 0.1, central corneal staining P < 0.001, conjunctival staining P < 0.01). This model-based analysis suggests a significant CyclASol effect for OSDI as symptom parameter (P < 0.01). The numbers of ocular adverse events were low in all treatment groups.Conclusions: CyclASol showed efficacy, safety, and tolerability at 2 concentrations in moderate-to-severe DED. In a direct head-to-head against open-label Restasis, CyclASol was found to have an earlier onset of action, as early as after 2 weeks of treatment, in relieving the signs of DED, as measured by corneal and conjunctival staining. The central region of the cornea, an important area for visual function in dry eye sufferers, was shown to have the most benefit from treatment. Excellent safety, tolerability, and comfort profile supports this new CsA formulation as having a positive benefit-to-risk ratio.
Purpose: Evaporation of the tear film is heavily discussed as one core reason for dry eye disease (DED). Subsequently, new artificial tear products are developed that specifically target this pathomechanism. Perfluorohexyloctane (F6H8, NovaTears®) from the family of semifluorinated alkanes is a novel substance that has been approved as a medical device, as a nonblurring wetting agent for the ocular surface.Methods: Thirty patients with hyperevaporative dry eye received F6H8 during a prospective, multicenter, observational 6-week study. Patients were advised to apply 1 drop 4 times daily in both eyes. Parameters assessed included best corrected visual acuity, intraocular pressure, Schirmer I test, tear fluid, tear film breakup time (TFBUT), corneal staining, meibum secretion, and Ocular Surface Disease Index (OSDI©).Results: From the 30 patients recruited, 25 completed the trial per protocol. Four patients discontinued F6H8 and 1 patient did not present for follow-up. F6H8 treatment led to significant reduction of corneal staining and significant increase of Schirmer I and TFBUT. In addition, OSDI score dropped significantly from a mean of 55 (±23.0) to 34 (±22.4). Visual acuity and ocular pressure did not change.Conclusions: This prospective observational study shows significant beneficial effects in patients suffering from evaporative DED, using F6H8 in all the relevant parameters tested. The decrease of the OSDI by a mean of 21 points was particularly remarkable and clearly exceeds minimal, clinical important differences for mild or moderate and severe disease. Overall, F6H8 (NovaTears) seems to be safe and effective in treating mild to moderate hyperevaporative DED.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.