Amacrine cells of the retina are conspicuously variable in their morphologies, their population demographics, and their ensuing functions. Vesicular glutamate transporter 3 (VGluT3) amacrine cells are a recently characterized type of amacrine cell exhibiting local dendritic autonomy. The present analysis has examined three features of this VGluT3 population, including their density, local distribution, and dendritic spread, to discern the extent to which these are interrelated, using male and female mice. We first demonstrate that Bax-mediated cell death transforms the mosaic of VGluT3 cells from a random distribution into a regular mosaic. We subsequently examine the relationship between cell density and mosaic regularity across recombinant inbred strains of mice, finding that, although both traits vary across the strains, they exhibit minimal covariation. Other genetic determinants must therefore contribute independently to final cell number and to mosaic order. Using a conditional KO approach, we further demonstrate that Bax acts via the bipolar cell population, rather than cell-intrinsically, to control VGluT3 cell number. Finally, we consider the relationship between the dendritic arbors of single VGluT3 cells and the distribution of their homotypic neighbors. Dendritic field area was found to be independent of Voronoi domain area, while dendritic coverage of single cells was not conserved, simply increasing with the size of the dendritic field. Bax-KO retinas exhibited a threefold increase in dendritic coverage. Each cell, however, contributed less dendrites at each depth within the plexus, intermingling their processes with those of neighboring cells to approximate a constant volumetric density, yielding a uniformity in process coverage across the population.SIGNIFICANCE STATEMENT Different types of retinal neuron spread their processes across the surface of the retina to achieve a degree of dendritic coverage that is characteristic of each type. Many of these types achieve a constant coverage by varying their dendritic field area inversely with the local density of like-type neighbors. Here we report a population of retinal amacrine cells that do not develop dendritic arbors in relation to the spatial positioning of such homotypic neighbors; rather, this cell type modulates the extent of its dendritic branching when faced with a variable number of overlapping dendritic fields to approximate a uniformity in dendritic density across the retina. 相似文献
Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment. 相似文献
The objectives of this study were to factor analyze the Moral Distress Scale–Revised (MDS-R) in NICU nurses and to evaluate the relationships among dimensions of the MDS-R and the demoralization, exhaustion, and loss of motive dimensions of the Burnout Measure (BM). A total of 142 NICU nurses completed modified pen-and-paper versions of the MDS-R and BM. Exploratory and confirmatory factor analyses showed that the MDS-R-14 was a relatively good fit for the data. The compromised care dimension predicted BM demoralization (β = 0.24) and exhaustion (β = 0.22), the futile care dimension predicted BM exhaustion (β = 0.18), and the untruthful care dimension predicted BM demoralization (β = .25). Strategies to mitigate moral distress and resulting burnout in NICU nurses should address futile care, compromised care, and untruthful care. 相似文献
ObjectivesSurvival extrapolation for chimeric antigen receptor T-cell therapies is challenging, owing to their unique mechanistic properties that translate to complex hazard functions. Axicabtagene ciloleucel is indicated for the treatment of relapse or refractory diffuse large B-cell lymphoma after 2 or more lines of therapy based on the ZUMA-1 trial. Four data snapshots are available, with minimum follow-up of 12, 24, 36, and 48 months. This analysis explores how survival extrapolations for axicabtagene ciloleucel using ZUMA-1 data can be validated and compared.MethodsThree different parametric modeling approaches were applied: standard parametric, spline-based, and cure-based models. Models were compared using a range of metrics, across the 4 data snapshot, including visual fit, plausibility of long-term estimates, statistical goodness of fit, inspection of hazard plots, point-estimate accuracy, and conditional survival estimates.ResultsStandard and spline-based parametric extrapolations were generally incapable of fitting the ZUMA-1 data well. Cure-based models provided the best fit based on the earliest data snapshot, with extrapolations remaining consistent as data matured. At 48 months, the maximum survival overestimate was 8.3% (Gompertz mixture-cure model) versus the maximum underestimate of 33.5% (Weibull standard parametric model).ConclusionsWhere a plateau in the survival curve is clinically plausible, cure-based models may be helpful in making accurate predictions based on immature data. The ability to reliably extrapolate from maturing data may reduce delays in patient access to potentially lifesaving treatments. Additional research is required to understand how models compare in broader contexts, including different treatments and therapeutic areas. 相似文献
ObjectivesTo determine the prevalence of restless legs syndrome (RLS) and RLS-mimic conditions, the risk factors for RLS, and whether RLS contributes to functional impairment in children and adolescents with attention-deficit/hyperactivity disorder (ADHD).MethodsADHD children and adolescents were prospectively studied at the outpatient psychiatric clinic. A trained registered nurse used the 2012 Revised International Restless Legs Syndrome Study Group diagnostic criteria to diagnose RLS. Sociodemographic data and medical records were reviewed. Weiss Functional Impairment Rating Scale-Parent Report (WFIRS-P) Thai version was used to identify association between RLS and 6 domains of function [family, school (learning), school (behavior), life skills, child self-concept, social activities, and risky activities].ResultsA total of 217 patients were included. Of those, 23 (11%) patients met the criteria for RLS, and 49 (23%) had RLS-mimic conditions. Those conditions included myalgia (30/49), habitual foot tapping (23/49), positional discomfort (20/49), leg ulcer/bruise (1/49), and arthralgia/arthritis (1/49). Binary logistic regression revealed first-degree relative having RLS symptom to be significantly associated with RLS in study patients (OR: 5.06, p < 0.01). Multivariate linear regression showed RLS to be independently associated with school (behavior) (Β = 1.18, p = 0.05) and life skills (Β = 2.36, p = 0.05) impairment.ConclusionsRLS was found to be common in ADHD children and adolescents. RLS-mimic conditions were found in two-thirds of patients who previously met 4 essential RLS criteria. First-degree relative with RLS symptom was associated with RLS, and RLS was associated with functional impairment in the life skills and school (behavior) domains. 相似文献
Background: Gait disorders are common in Parkinson’s disease patients who respond poorly to dopaminergic treatment. Blockade of adenosine A2A receptors is expected to improve gait disorders. Istradefylline is a first-in-class selective adenosine A2A receptor antagonist with benefits for motor complications associated with Parkinson’s disease.
Research design and methods: This multicenter, open-label, single-group, prospective interventional study evaluated changes in total gait-related scores of the Part II/III Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) and Freezing of Gait Questionnaire (FOG-Q) in 31 Parkinson’s disease patients treated with istradefylline. Gait analysis by portable gait rhythmogram was performed.
Results: MDS-UPDRS Part III gait-related total scores significantly decreased at Weeks 4–12 from baseline with significant improvements in gait, freezing of gait, and postural stability. Significant decreases in MDS-UPDRS Part II total scores and individual item scores at Week 12 indicated improved daily living activities. At Week 12, there were significant improvements in FOG-Q, new FOG-Q, and overall movement per 48 h measured by portable gait rhythmogram. Adverse events occurred in 7/31 patients.
Conclusions: Istradefylline improved gait disorders in Parkinson’s disease patients complicated with freezing of gait, improving their quality of life. No unexpected adverse drug reactions were identified.