The exposure of the developing human embryo to ethanol results in a spectrum of disorders involving multiple organ systems, including the visual system. One common phenotype seen in humans exposed to ethanol in utero is microphthalmia. The objective of this study was to describe the effects of ethanol during retinal neurogenesis in a model organism, the zebrafish, and to pursue the potential mechanisms by which ethanol causes microphthalmia. Zebrafish embryos were exposed to 1% or 1.5% ethanol from 24 to 48 h after fertilization, a period during which the retinal neuroepithelium undergoes rapid proliferation and differentiation to form a laminated structure composed of different retinal cell types. Ethanol exposure resulted in significantly reduced eye size immediately following the treatment, and this microphthalmia persisted through larval development. This reduced eye size could not entirely be accounted for by the accompanying general delay in embryonic development. Retinal cell death was only slightly higher in ethanol-exposed embryos, although cell death in the lens was extensive in some of these embryos, and lenses were significantly reduced in size as compared to those of control embryos. The initiation of retinal neurogenesis was not affected, but the subsequent waves of cell differentiation were markedly reduced. Even cells that were likely generated after ethanol exposure-rod and cone photoreceptors and Müller glia-were delayed in their expression of cell-specific markers by at least 24 h. We conclude that ethanol exposure over the time of retinal neurogenesis resulted in persistent microphthalmia due to a combination of an overall developmental delay, lens abnormalities, and reduced retinal cell differentiation.
Background Microphthalmia (reduced eye size), generally accompanied by vision defects, is a hallmark of fetal alcohol spectrum disorder (FASD) in humans. In zebrafish, embryonic ethanol exposure over the time of retinal neurogenesis also results in microphthalmia. This microphthalmia is in part the consequence of reduced retinal cell differentiation, including photoreceptors. Here we pursue 2 signaling pathways implicated in other aspects of FASD pathogenesis: retinoic acid (RA) and Sonic hedgehog (Shh). Methods We evaluated markers for RA and Shh signaling within the eyes of embryos treated with ethanol during the period of retinal neurogenesis. We also perrormed rescue experiments using administration of exogenous RA and microinjection of cholesterol, which augments Shh signaling. Results Using sequential or co-treatments, RA did not rescue ethanol-induced microphthalmia at any concentration tested. In addition, RA itself caused microphthalmia, although the underlying mechanisms were distinct from those or ethanol. Interestingly, RA treatment appeared to recover photoreceptor differentiation in a concentration-dependent manner. This may be an independent effect or exogenous RA, as ethanol treatment alone did not alter RA signaling in the eye. Cholesterol injection also did not rescue ethanol-induced microphthalmia at any concentration tested, and ethanol treatments did not alter expression of shh, or of ptc-2, which is normally regulated by Shh signaling. Conclusions Together these findings indicate that, during the time of retinal neurogenesis, effects of ethanol on eye development are likely independent of the RA and Shh signaling pathways. These studies suggest that FASD intervention strategies based upon augmentation or RA or Shh signaling may not prevent ethanol-induced microphthalmia.
Epidemiological studies provide strong evidence that obstructive sleep apnea (OSA) is associated with cardiovascular complications such as systemic hypertension, congestive heart failure, and atrial fibrillation. Successful OSA treatment with continuous positive airway pressure (CPAP) has resulted in coincident reductions in systemic hypertension, improvements in left ventricular systolic function, and reductions in sympathetic nervous activity. These data suggest that successful treatment of OSA may reduce cardiovascular morbidity in such patients. Although CPAP is the more successful treatment for OSA when used properly and consistently, its clinical success is often limited by poor patient and partner acceptance, which leads to suboptimal compliance. Oral appliances or upper airway surgeries are considered a second line of treatment for patients with mild to moderate OSA who do not comply with or refuse long-term CPAP treatment. Oral devices such as mandibular repositioning appliances were recently shown to improve arterial hypertension in OSA patients. Electrical stimulation of the hypoglossal nerve is a new investigational therapy for patients with moderate to severe OSA. This new treatment option, if proven effective, may provide cardiovascular benefits secondary to treating OSA.
BACKGROUND: The incidence rate of stroke in hospitalized patients ranges between 2% and 17% of all strokes—a higher rate than in the community. Delays in recognition and management of stroke in hospitalized patients lead to worse outcomes. At our hospital, the existing in-hospital stroke (IHS) code showed low usage and effectiveness. In a quality improvement (QI) project, we aimed to improve the identification of and the quality of care for inpatient strokes. METHODS: A nurse-driven IHS protocol was implemented, which alerted a specialized stroke team and cleared the computed tomography (CT) scanner. The protocol focused on prioritizing staff education, simplifying the process, empowering staff to activate an IHS code, ensuring adequate support and teamwork, identifying well-defined quality metrics (eg, time to CT and documentation tool use), and providing feedback communication. We analyzed 2 years of postimplementation IHS data for impact on stroke detection and outcomes. RESULTS: In the 2 years post QI, there was a more than 10-fold increase in IHS (pre-QI, n = 8; first year post QI, n = 94; second year post QI, n = 123). In the post-QI cohort, after excluding patients with missing information (n = 26), 69 cases had new stroke diagnoses (63 ischemic, 6 hemorrhagic), and 148 were stroke mimics. The mean (SD) time from IHS to CT was 18.7 (7.0) minutes. Of the 63 new ischemic stroke cases, 25 (39.7%) were treated with thrombolytic therapy and/or mechanical thrombectomy. CONCLUSION: The new IHS protocol has led to a marked increase in cases identified, rapid evaluation, and high utilization rate of acute stroke therapies.
The mechanisms through which ethanol exposure results in developmental defects remain unclear. We used the zebrafish model to elucidate eye-specific mechanisms that underlie ethanol-mediated microphthalmia (reduced eye size), through time-series microarray analysis of gene expression within eyes of embryos exposed to 1.5% ethanol. 62 genes were differentially expressed (DE) in ethanol-treated as compared to control eyes sampled during retinal neurogenesis (24-48 hours post-fertilization). The EDGE (extraction of differential gene expression) algorithm identified >3000 genes DE over developmental time in ethanol-exposed eyes as compared to controls. The DE lists included several genes indicating a mis-regulated cellular stress response due to ethanol exposure. Combined treatment with sub-threshold levels of ethanol and a morpholino targeting heat shock factor 1 mRNA resulted in microphthalmia, suggesting convergent molecular pathways. Thermal preconditioning partially prevented ethanol-mediated microphthalmia while maintaining Hsf-1 expression. These data suggest roles for reduced Hsf-1 in mediating microphthalmic effects of embryonic ethanol exposure.
Addiction to substances such as alcohol, cocaine, opioids, and methamphetamine poses a continuing clinical and public challenge globally. Despite progress in understanding substance use disorders, challenges remain in their treatment. Some of these challenges include limited ability of therapeutics to reach the brain (blood-brain barrier), adverse systemic side effects of current medications, and importantly key aspects of addiction not addressed by currently available treatments (such as cognitive impairment). Inability to sustain abstinence or seek treatment due to cognitive deficits such as poor decision-making and impulsivity is known to cause poor treatment outcomes. In this review, we provide an evidenced-based rationale for intranasal drug delivery as a viable and safe treatment modality to bypass the blood-brain barrier and target insulin to the brain to improve the treatment of addiction. Intranasal insulin with improvement of brain cell energy and glucose metabolism, stress hormone reduction, and improved monoamine transmission may be an ideal approach for treating multiple domains of addiction including memory and impulsivity. This may provide additional benefits to enhance current treatment approaches.
Background Prior studies have indicated high rates of vascular risk factors, but little is known about stroke in Hmong. Methods and Results The institutional Get With The Guidelines (GWTG) database was used to identify patients discharged with acute ischemic stroke, intracerebral hemorrhage, or subarachnoid hemorrhage between 2010 and 2019. Hmong patients were identified using clan names and primary language. Univariate analysis was used to compare Hmong and White patients. A subarachnoid hemorrhage comparison was not conducted because of the small sample size. We identified 128 Hmong patients and 3084 White patients. Hmong patients had more prevalent hemorrhagic stroke (31% versus 15%; P <0.0016). In the acute ischemic stroke cohort, compared with White patients, Hmong patients were younger (60±13 versus 71±15 years; P <0.0001), presented to the emergency department almost 4 hours later; and had a lower thrombolysis usage rate (6% versus 14%; P =0.03496), worse lipid profile, higher hemoglobin A 1C , similar stroke severity, and less frequent discharge to rehabilitation facilities. The most common ischemic stroke mechanism for Hmong patients was small‐vessel disease. In the intracerebral hemorrhage cohort, Hmong patients were younger (55±13 versus 70±15 years; P <0.0001), had higher blood pressure, and had a lower rate of independent ambulation on discharge (9% versus 30%; P =0.0041). Conclusions Hmong patients with stroke were younger and had poorer risk factor control compared with White patients. There was a significant delay in emergency department arrival and low use of acute therapies among the Hmong acute ischemic stroke cohort. Larger studies are needed to confirm these observations, but action is urgently needed to close gaps in primary care and stroke health literacy.
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.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.