Despite the increasing demographic diversity of the United States’ aging population, there remain significant gaps in post-mortem research investigating the ethnoracial heterogeneity in the neuropathological landscape of Alzheimer Disease (AD). Most autopsy-based studies have focused on cohorts of non-Hispanic White decedents (NHWD), with few studies including Hispanic decedents (HD). We aimed to characterize the neuropathologic landscape of AD in NHWD (n = 185) and HD (n = 92) evaluated in research programs across three institutions: University of California San Diego, University of California Davis, and Columbia University. Only persons with a neuropathologic diagnosis of intermediate/high AD determined by NIA Reagan and/or NIA-AA criteria were included. A frequency-balanced random sample without replacement was drawn from the NHWD group using a 2:1 age and sex matching scheme with HD. Four brain areas were evaluated: posterior hippocampus, frontal, temporal, and parietal cortices. Sections were stained with antibodies against Aβ (4G8) and phosphorylated tau (AT8). We compared the distribution and semi-quantitative densities for neurofibrillary tangles (NFTs), neuropil threads, core, diffuse, and neuritic plaques. All evaluations were conducted by an expert blinded to demographics and group status. Wilcoxon’s two-sample test revealed higher levels of neuritic plaques in the frontal cortex (p = 0.02) and neuropil threads (p = 0.02) in HD, and higher levels of cored plaques in the temporal cortex in NHWD (p = 0.02). Results from ordinal logistic regression controlling for age, sex, and site of origin were similar. In other evaluated brain regions, semi-quantitative scores of plaques, tangles, and threads did not differ statistically between groups. Our results demonstrate HD may be disproportionately burdened by AD-related pathologies in select anatomic regions, particularly tau deposits. Further research is warranted to understand the contributions of demographic, genetic, and environmental factors to heterogeneous pathological presentations.
Background Irreversible sensorineural auditory loss has been reported in humans treated with aminoglycosides but not in horses. Objective Investigate if auditory loss occurs in horses treated using the recommended IV daily dosage of gentamicin for 7 consecutive days. Animals Ten healthy adult horses (7‐15 years; females and males, 5 each). Methods Prospective study. Physical and neurological examinations and renal function tests were performed. Gentamicin sulfate was administered at a dosage of 6.6 mg/kg via the jugular vein on alternating sides for 7 days. Gentamicin peak and trough concentrations were measured. Horses were sedated using detomidine hydrochloride IV to perform brainstem auditory evoked responses (BAER) before the first dose, immediately after the last dose, and 30 days after the last dose. Peaks latencies, amplitudes, and amplitude ratios were recorded. Data from the second and last BAER were compared to results at baseline. Bone conduction was performed to rule out conduction disorders. Results Seven horses had auditory loss: complete bilateral (N = 1), complete unilateral (N = 2), and partial unilateral (N = 4). Based on physical examination and BAER results, sensorineural auditory loss was suspected. Absent bone conduction ruled out a conduction disorder and further supported sensorineural auditory loss in horses with completely absent BAER. Auditory dysfunction was reversible in 4 of 7 horses. Conclusions and Clinical Importance Gentamicin at recommended doses may cause sensorineural auditory loss in horses that might be irreversible. Follow‐up studies are needed to investigate if other dosing protocols present a similar risk.
The aims of this study were: 1) to compare the tape weight and associated weight-estimation formula to evaluate weight gain in pregnant mares, and 2) to develop a mathematical model to estimate the weight of pregnant mares using body measurements. Thirty-four criollo-type mares were evaluated every two weeks during the middle and late pregnancy. The mares were weighed on a livestock scale, and we estimated body weight using tape weights and an associated body-weight estimation formula. Also, heart-girth circumference (heartgirth) and abdominal circumference were measured; the latter at the 12th intercostal space (12th ICS) and 18th rib (18th Rib), to use in a mathematical model to estimate the weight of pregnant mares. Observations were divided into three periods of pregnancy: 5th to 7 h month, 7th to 9 h month, and 9th to 11th month. Mares in late pregnancy showed an increase in actual weight and an increase in 12th ICS and 18th Rib measurements. Tape weight and body-weight estimation formula underestimated the weight of pregnant mares. However, the regression model using heart-girth circumference, 12th ICS, and 18th Rib measurements showed high correlation (r2 = 0.87, P<0.001) with actual weight. Finally, the alternative methods usually used in horses are not accurate to estimate body weight in pregnant mares. In conclusion, the regression model Y=-540.143 + (heartgirth x 3.068) + (12th ICS x 1.278) + (18th Rib x 0.944) can be used to estimate body weight in pregnant mares from the 5th to 11th months of pregnancy.
Objectives To report red cell distribution width (RDW) values, to calculate RDW‐to‐platelet ratio (RPR), and to investigate a possible correlation of RDW and RPR index values in neonatal foals classified as healthy or at risk based on clinical information from a population of foals up to 24 hours of life. Design Retrospective study conducted from records and CBCs of foals born between June and November from 2018 to 2020 foaling seasons. Setting Breeding farm. Animals Three hundred and nine neonatal full‐term Thoroughbred foals. Interventions None. Measurements and Main Results Foals were evaluated by a veterinarian within 15 minutes after birth, and a blood sample was collected within 24 hours of life. Based on clinical information, 88 of 309 foals (28.4%) were considered at risk of perinatal disease, and 201 were healthy. Mean gestational age for the foals was 346.3 ± 9.7 days. RDW values did not differ between groups. Gestational length demonstrated to have a negative correlation with RDW (r = –0.156, P = 0.005) and mean corpuscular volume (r = –0.135, P = 0.01), indicating a link of these variables to foal maturity. RPR index was higher for at‐risk (0.073 ± 0.018) than for healthy foals (0.068 ± 0.014, P = 0.01). Conclusion RPR might be a promising early indicator of disease for the field triage of neonatal foals.
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.