Bilateral temporoparietal hypoperfusion has been frequently observed early in the Alzheimer's disease (AD) process. The beta-amyloid (A beta) peptide is believed to play a central role in the pathogenesis of AD. In vitro experiments have shown that freshly solubilized A beta enhances constriction of cerebral and peripheral vessels. We proposed that in vivo, A beta would also have vasoactive properties. To test this hypothesis, we intraarterially infused freshly solubilized A beta 1-40 in rats and observed changes in peripheral blood pressure, cerebral blood flow, and cerebrovascular resistance. We found that infusion of A beta in vivo significantly increased the blood pressure in hypotensive rats but not in normotensive and hypertensive rats. Moreover, A beta infusion also resulted in a decreased blood flow and increased vascular resistance specifically in cerebral cortex but not in heart or kidneys. These data suggest that A beta has a direct and specific constrictive effect on cerebral vessels in vivo, which may contribute to the cerebral hypoperfusion observed early in the AD process.
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http://dx.doi.org/10.1111/j.1749-6632.2000.tb06363.x | DOI Listing |
Mol Omics
January 2025
Departamento de Innovación Biomédica, Centro de Investigación Científica y de Educación Superior de Ensenada, Baja California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860, Ensenada, Baja California, Mexico.
Metabolic associated steatohepatitis characterized by lipid accumulation, inflammation and fibrosis, is a growing global health issue, contributing to severe liver-related mortality. With limited effective treatments available, there is an urgent need for novel therapeutic strategies. , rich in antioxidants, offers potential for combating steatohepatitis, but its cytotoxicity presents challenges.
View Article and Find Full Text PDFHematology
December 2025
Division of Hematology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, and King Chulalongkorn Memorial Hospital, Thai Red Cross, Bangkok, Thailand.
Background: Hemoglobin (Hb) Hekinan is a prevalent α-globin variant frequently missed in thalassemia screening centers using high-performance liquid chromatography (HPLC) or capillary electrophoresis. This study aims to investigate the hematological and molecular characteristics of Hb Hekinan in a large cohort.
Methods: Hb variants were identified using isoelectric focusing (IEF) and HPLC.
Alzheimers Dement
January 2025
Department of Neuroscience, City University of Hong Kong, Hong Kong, Hong Kong.
Introduction: Antisense oligonucleotides (ASOs) have shown promise in reducing amyloid precursor protein (APP) levels in neurons, but their effects in astrocytes, key contributors to neurodegenerative diseases, remain unclear. This study evaluates the efficacy of APP ASOs in astrocytes derived from an individual with Down syndrome (DS), a population at high risk for Alzheimer's disease (AD).
Methods: Human induced pluripotent stem cells (hiPSCs) from a healthy individual and an individual with DS were differentiated into astrocytes.
Alzheimers Dement
January 2025
Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.
Introduction: Plasma phosphorylated tau (p-tau) biomarkers have improved Alzheimer's disease (AD) diagnosis, but data from diverse Asian populations are limited. This study evaluated plasma p-tau217 and p-tau181 levels in Korean and Taiwanese populations.
Methods: All participants (n = 270) underwent amyloid positron emission tomography (PET) and blood tests.
J Pestic Sci
November 2024
Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University.
We investigated whether various modified cyclodextrins (CDs) and emulsifiers could be applied as dispersing agents in ready biodegradability tests of poorly water-soluble substances. Trimethylated α-, β-, and γ-CDs and partially methylated β-CD were not biodegraded in the test period but accelerated the biodegradation of octabenzone and anthraquinone. The process by which trimethylated α-, β-, and γ-CDs enhance the biodegradation of test substances has been partially uncovered.
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