A cellular resolution atlas of Broca's area.

Brain cells are arranged in laminar, nuclear, or columnar structures, spanning a range of scales. Here, we construct a reliable cell census in the frontal lobe of human cerebral cortex at micrometer resolution in a magnetic resonance imaging (MRI)-referenced system using innovative imaging and analysis methodologies. MRI establishes a macroscopic reference coordinate system of laminar and cytoarchitectural boundaries. Cell counting is obtained with a digital stereological approach on the 3D reconstruction at cellular resolution from a custom-made inverted confocal light-sheet fluorescence microscope (LSFM). Mesoscale optical coherence tomography enables the registration of the distorted histological cell typing obtained with LSFM to the MRI-based atlas coordinate system. The outcome is an integrated high-resolution cellular census of Broca's area in a human postmortem specimen, within a whole-brain reference space atlas.

Comparative neuropathology in aging primates: A perspective.

While humans exhibit a significant degree of neuropathological changes associated with deficits in cognitive and memory functions during aging, non-human primates (NHP) present with more variable expressions of pathological alterations among individuals and species. As such, NHP with long life expectancy in captivity offer an opportunity to study brain senescence in the absence of the typical cellular pathology caused by age-related neurodegenerative illnesses commonly seen in humans. Age-related changes at neuronal population, single cell, and synaptic levels have been well documented in macaques and marmosets, while age-related and Alzheimer's disease-like neuropathology has been characterized in additional species including lemurs as well as great apes. We present a comparative overview of existing neuropathologic observations across the primate order, including classic age-related changes such as cell loss, amyloid deposition, amyloid angiopathy, and tau accumulation. We also review existing cellular and ultrastructural data on neuronal changes, such as dendritic attrition and spine alterations, synaptic loss and pathology, and axonal and myelin pathology, and discuss their repercussions on cellular and systems function and cognition.

Epidemiology of Persistent Postsurgical Pain Manifesting as Dry Eye-Like Symptoms After Cataract Surgery.

PURPOSE: To evaluate the epidemiology of persistent postsurgical pain (PPP) manifesting as dry eye (DE)-like symptoms 6 months after surgery. METHODS: This single-center study included 119 individuals whose cataract surgeries were performed by a single surgeon at the Bascom Palmer Eye Institute and who agreed to participate in a phone survey 6 months after surgery. Patients were divided into 2 groups: the PPP group was defined as those with a Dry Eye Questionnaire-5 score ≥6 and without PPP as those with a Dry Eye Questionnaire-5 score <6 at 6 months after cataract surgery. RESULTS: Mean age of the study population was 73 ± 8.0 years; 55% (n = 66) were female. PPP was present in 34% (n = 41) of individuals 6 months after surgery. Factors associated with an increased risk of PPP were female sex [odds ratio (OR) = 2.68, 95% confidence interval (CI) = 1.20-6.00, P = 0.01], autoimmune disorder (OR = 13.2, CI = 1.53-114, P = 0.007), nonocular chronic pain disorder (OR = 4.29, CI = 1.01-18.1, P = 0.06), antihistamine use (OR = 6.22, CI = 2.17-17.8, P = 0.0003), antireflux medication use (OR = 2.42, CI = 1.04-5.66, P = 0.04), antidepressant use (OR = 3.17, CI = 1.31-7.68, P = 0.01), anxiolytic use (OR = 3.38, CI = 1.11-10.3, P = 0.03), and antiinsomnia medication use (OR = 5.28, CI = 0.98-28.5, P = 0.047). PPP patients also reported more frequent use of artificial tears (P < 0.0001), higher ocular pain levels (P < 0.0001), and greater neuropathic ocular pain symptoms, including burning (P = 0.001), wind sensitivity (P = 0.001), and light sensitivity (P < 0.0001). CONCLUSIONS: PPP in the form of persistent DE-like symptoms is present in approximately 34% of individuals 6 months after cataract surgery. The frequency of PPP after cataract surgery is comparable to that of other surgeries including laser refractive surgery, dental implants, and genitourinary procedures.