In anaesthetized guinea pigs, ventilated with ambient air, the peripheral haemodynamics and oxygen transport characteristics have been studied following a blood exchange transfusion with rat erythrocytes suspended in guinea pig plasma. Since the rat haemoglobin exhibited a lower oxygen affinity than guinea pig haemoglobin, the oxygen partial pressure at 50% of oxygen haemoglobin saturation (P50) increased from 25.2 +/- 1.1 to 37.2 +/- 0.9 mm Hg (n = 10). This increase in P50 was accompanied by a significant increase in arterial oxygen partial pressure (PaO2) and in arterio-venous difference (AVDO2). Cardiac output (Q) was decreased significantly, but oxygen consumption (VO2) remained within control values. The increase in P50 was associated with a venous oxygen partial pressure (P-VO2) which remained constant but an increase in blood lactate concentration was observed. Control exchange transfusion with fresh guinea pig blood had no effect on acid-base status, on oxygen transport, or on peripheral resistance. The sudden reduction in haemoglobin oxygen affinity induced an increase in peripheral resistance with a decrease in cardiac output, the arterial systemic pressure being maintained. These results suggested that an acute decrease in haemoglobin oxygen affinity was compensated for by a simultaneous diminution of overall tissue blood flow and reduction of capillary recruitment.
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http://dx.doi.org/10.1016/0034-5687(83)90099-3 | DOI Listing |
Alzheimers Dement
January 2025
Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA.
Introduction: Iron-mediated cell death (ferroptosis) is a proposed mechanism of Alzheimer's disease (AD) pathology. While iron is essential for basic biological functions, its reactivity generates oxidants which contribute to cell damage and death.
Methods: To further resolve mechanisms of iron-mediated toxicity in AD, we analyzed post mortem human brain and ApoEFAD mice.
J Ginseng Res
January 2025
Department of Integrative Biotechnology, Biomedical Institute for Convergence of SKKU (BICS), Sungkyunkwan University, Suwon, Republic of Korea.
Background: Ginseng is processed into several types such as white ginseng, red ginseng, and black ginseng, according to the processing methods such as drying, steaming, and heating. These processing conditions can change the portion of the useful ingredients. Recently, new processing method was established to develop 'lymphanax', an aged fresh white ginseng prepared under anaerobic condition.
View Article and Find Full Text PDFBr J Psychiatry
January 2025
Department of Psychology, Nottingham Trent University, UK; and Institute of Human Sciences, University of Oxford, UK.
Background: Reliable and specific biomarkers that can distinguish autism spectrum disorders (ASDs) from commonly co-occurring attention-deficit/hyperactivity disorder (ADHD) are lacking, causing misses and delays in diagnosis, and reducing access to interventions and quality of life.
Aims: To examine whether an innovative, brief (1-min), videogame method called Computerised Assessment of Motor Imitation (CAMI), can identify ASD-specific imitation differences compared with neurotypical children and children with ADHD.
Method: This cross-sectional study used CAMI alongside standardised parent-report (Social Responsiveness Scale, Second Edition) and observational measures of autism (Autism Diagnostic Observation Schedule-Second Edition; ADOS-2), ADHD (Conners) and motor ability (Physical and Neurological Examination for Soft Signs).
J Hepatocell Carcinoma
January 2025
Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Introduction: Hepatocellular carcinoma (HCC) disproportionately affects Hispanic persons with higher age-specific incidence and increased mortality rates compared to non-Hispanic Whites. These high rates of incidence and mortality may be explained by the variation in risk factors. Given the high prevalence of type 2 diabetes mellitus (DM) among the Hispanic population, we aimed to assess the risk and prognosis of HCC in Mexican Americans with type 2 DM with consideration of treatment for DM.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Institute of Technology, University of the National Education Commission, Podchorążych 2, 30-084 Kraków, Poland.
In this work, three composite materials based on Terfenol-D and PZT-type material were obtained with a classic sintering method using a combination of 0-3 phases, where the ferroelectric phase was doped PZT material (P) and the magnetic phase was Terfenol-D (T). The percentage of P and T components in the composites was variable, i.e.
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