Ytterbium-169 has been developed as a possible replacement for Iridium-192 and Iodine-125. The Theory of Dual Radiation Action predicts that the initial slope of the cell survival curve and therefore the relative biological effect at low dose rate is proportional to dose average lineal energy, yd, which is the microscopic analog of the dose average linear energy transferred. The quality factor used in radiation protection has been shown to be a function of the frequency average lineal energy, yf. Single event microdosimetric spectra for 60Co, 137Cs, 192Ir, 125I and 169Yb were measured in air and at several depths in phantom with a Rossi proportional counter. These spectra show marked differences between sources. The microscopic analogs of the track average and dose average LET, (yd and yf, respectively) differ between isotopes by factors of two or even higher in comparison to megavoltage electron beams. These yd's and yf's for 169Yb are consistently higher when compared to 60Co or 137Cs but are approximately equal to those for 125I. Values of yf and yd for 192Ir are intermediate between 60Co and 169Yb. The Theory of Dual Radiation Action predicts a low dose rate RBE (assuming a 1 micron effective site diameter) compared to 60Co (in air) of: 1.00 for 137Cs, 1.29 for 192Ir, 1.60 for 169Yb and 1.77 for 125I.
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http://dx.doi.org/10.1016/0360-3016(92)90021-9 | DOI Listing |
Lancet Neurol
February 2025
Janssen Research & Development, a Johnson & Johnson Company, Titusville, NJ, USA.
Background: Given burdensome side-effects and long latency for efficacy with conventional agents, there is a continued need for generalised myasthenia gravis treatments that are safe and provide consistently sustained, long-term disease control. Nipocalimab, a neonatal Fc receptor blocker, was associated with dose-dependent reductions in total IgG and anti-acetylcholine receptor (AChR) antibodies and clinically meaningful improvements in the Myasthenia Gravis Activities of Daily Living (MG-ADL) scale in patients with generalised myasthenia gravis in a phase 2 study. We aimed to assess the safety and efficacy of nipocalimab in a phase 3 study.
View Article and Find Full Text PDFNutrients
January 2025
Cambridge Centre for Sport and Exercise Sciences (CCSES), Faculty of Science and Engineering, Anglia Ruskin University, Cambridge CB1 1PT, UK.
Background/objectives: There is current scientific interest pertaining to the therapeutic effects of olive-derived polyphenols (ODPs), in particular their associated anti-inflammatory properties, following the wealth of research surrounding the physiological impact of the Mediterranean Diet (MD). Despite this association, the majority of the current literature investigates ODPs in conjunction with metabolic diseases. There is limited research focusing on ODPs and acute inflammation following exercise, regardless of the knowledge surrounding the elevated inflammatory response during this time.
View Article and Find Full Text PDFMedicina (Kaunas)
December 2024
Centre of Clnical and Preclinical Research, MEDIPARK-University Research Park, Pavol Jozef Safarik University, Trieda SNP 1, 040 11 Kosice, Slovakia.
Metabolic syndrome (MS) represents several diseases encompassing a heterogeneous group of biochemical and physiological abnormalities characterized by structural and functional alterations in the myocardium, including the endothelium of the coronary arteries. MS also affects a substantial portion of the global population. Understanding the risk factors, the development and treatment associated with MS are of paramount importance for early identification, treatment and prevention.
View Article and Find Full Text PDFAnimals (Basel)
January 2025
Department of Animal Nutrition, Faculty of Veterinary Medicine, Afyon Kocatepe University, ANS Campus, Afyonkarahisar 03200, Türkiye.
This research was carried out to determine the effects of potassium humate on the lactation performance and metabolic parameters of dairy cows during the transition period. Potassium humate was added to the concentrate feed at the following levels: (a) control (0%), (b) 0.5%, (c) 1%, (d) 1.
View Article and Find Full Text PDFAnimals (Basel)
January 2025
Neurophysiology of Pain, Behavior and Assessment of Welfare in Domestic Animals, Department of Animal Production and Agriculture, Universidad Autónoma Metropolitana (UAM), Mexico City 04960, Mexico.
Pain management requires the identification of certain indicators to recognize pain. Various tools have been suggested to achieve an objective evaluation, including infrared thermography (IRT). The objective of this study was to assess the facial thermal nociceptive response produced by the use of cannabidiol (CBD) alone and in combination with meloxicam in female dogs undergoing elective ovariohysterectomy anesthetized with isoflurane.
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