Elevated Hippocampal CRMP5 Mediates Chronic Stress-Induced Cognitive Deficits by Disrupting Synaptic Plasticity, Hindering AMPAR Trafficking, and Triggering Cytokine Release.

Chronic stress is a critical risk factor for developing depression, which can impair cognitive function. However, the underlying mechanisms involved in chronic stress-induced cognitive deficits remain unclear. Emerging evidence suggests that collapsin response mediator proteins (CRMPs) are implicated in the pathogenesis of psychiatric-related disorders. Thus, the study aims to examine whether CRMPs modulate chronic stress-induced cognitive impairment. We used the chronic unpredictable stress (CUS) paradigm to mimic stressful life situations in C57BL/6 mice. In this study, we found that CUS-treated mice exhibited cognitive decline and increased hippocampal CRMP2 and CRMP5 expression. In contrast to CRMP2, CRMP5 levels strongly correlated with the severity of cognitive impairment. Decreasing hippocampal CRMP5 levels through shRNA injection rescued CUS-induced cognitive impairment, whereas increasing CRMP5 levels in control mice exacerbated memory decline after subthreshold stress treatment. Mechanistically, hippocampal CRMP5 suppression by regulating glucocorticoid receptor phosphorylation alleviates chronic stress-induced synaptic atrophy, disruption of AMPA receptor trafficking, and cytokine storms. Our findings show that hippocampal CRMP5 accumulation through GR activation disrupts synaptic plasticity, impedes AMPAR trafficking, and triggers cytokine release, thus playing a critical role in chronic stress-induced cognitive deficits.

Loss of Autonomy: Likely Dementia and Living Arrangement Transitions Among Mexicans and Mexican Americans.

BACKGROUND AND OBJECTIVES: To examine the role of probable dementia on changes in living arrangements and mortality among very old Mexicans and Mexican Americans in 2 different nations. RESEARCH DESIGN AND METHODS: We employ the Hispanic Established Population for the Epidemiologic Study of the Elderly and the Mexican Health and Aging Study, 2 comparable longitudinal data sets, to identify predictors of changes in living arrangements using multinomial logistic regression, controlling for cognitive status, demographic characteristics, and resources. RESULTS: In Mexico, women with dementia who lived alone at baseline were more likely to become part of an extended family household than men with similar levels of cognitive impairment. A similar pattern emerges for the oldest Mexican-American women. Spousal loss increases the likelihood of living alone for women in the United States regardless of dementia. Although dementia elevates the risk of mortality for men living alone in the United States, in both countries, women in their 90s who lived alone with dementia had a lower risk of mortality relative to men. DISCUSSION AND IMPLICATIONS: Longer life spans increase the risk of living alone with dementia in both countries, especially for women. Older individuals in both countries face financial hardships. Mexicans have limited formal options in dementia care. Mexican Americans with dementia continue to live alone despite low income although, unlike the Mexicans, they have access to Medicaid long-term care. For Mexico and the United States, the growing number of older individuals with dementia represents a growing public health concern.

Deep phototherapeutic keratectomy for Schnyder corneal dystrophy.

We report a case of Schnyder corneal dystrophy (SCD) treated with deep phototherapeutic keratectomy (PTK). A 33-year-old man presented with a 5-year history of blurred vision and corneal haze in both eyes. Slit-lamp examination revealed needle-like subepithelial crystalline depositions and prominent arcus lipoides bilaterally. Similar clinical findings were observed in the patient's father. A diagnosis of SCD was made on the basis of the clinical presentation. PTK was performed using a multizone, multipass, and shoot and check technique with the WaveLight EX500 excimer laser. After 22 months of follow-up, the best-corrected visual acuity had increased from 0.5 to 0.9 in the right eye and from 0.3 to 0.9 in the left eye. SCD is rare but has a unique ocular presentation, which facilitates the diagnosis. PTK can increase patients' visual acuity and eliminate the need for aggressive management through penetrating keratoplasty or deep anterior lamellar keratoplasty.

Field Emission Characteristics of the Structure of Vertically Aligned Carbon Nanotube Bundles.

In this study, we performed thermal chemical vapor deposition for growing vertically aligned carbon nanotube (VACNT) bundles for a field emitter and applied photolithography for defining the arrangement pattern to simultaneously compare square and hexagonal arrangements by using two ratios of the interbundle distance to the bundle height (R) of field emitters. The hexagon arrangement with R = 2 had the lowest turn-on electric field (E to) and highest enhancement factor, whereas the square arrangement with R = 3 had the most stable field emission (FE) characteristic. The number density can reveal the correlation to the lowest E to and highest enhancement factor more effectively than can the R or L. The fluorescent images of the synthesized VACNT bundles manifested the uniformity of FE currents. The results of our study indicate the feasibility of applying the VACNT field emitter arrangement to achieve optimal FE performance.