A method is described for screening potentially useful photoprotective agents against UVA radiation by the use of immediate pigment darkening as an end point. Threshold doses of immediate pigment darkening showed a log normal distribution and the response was found to obey dose-reciprocity at irradiance levels below 50 mW/cm2. With this procedure, several marketed sunscreens containing benzophenone-3 as the only UVA absorber were found to have poor UVA protection factors, whereas those containing combinations of benzophenone-3 and butyl methoxydibenzoyl methane or melanin were more effective. There was no correlation between the sun protection factor cited on the label and the calculated immediate pigment darkening-protection factor.
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http://dx.doi.org/10.1016/0190-9622(91)70193-6 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Department of Sociology, University of California, Irvine, CA 92697-5100.
In recent years, Brazil's non-White (Brown and Black) population became a numerical majority for the first time since the 19th century. Although we know this change was mostly due to racial reclassification, we do not know how such changes are related to skin color, the primary marker of race in Brazil. Using data from six Latin American Public Opinion Project (LAPOP), or America's Barometer, surveys from 2010 to 2023, we examine how changes in racial self-identification (White, Brown, or Black) are related to respondent skin color (light, medium, or dark).
View Article and Find Full Text PDFJ Orthop Case Rep
December 2024
Department of Orthopaedics, Government Medical College Trivandrum, Kerala, India.
Introduction: Alkaptonuria is a rare metabolic disorder that follows an autosomal recessive genetic inheritance pattern. It is distinguished by the buildup of homogentisic acid in tissues due to deficient homogentisic acid oxidase enzyme activity. The excess homogentisic acid is expelled through urine, darkening it on oxidation.
View Article and Find Full Text PDFAm J Transl Res
October 2024
Department of Emergency, The First Affiliated Hospital of Gannan Medical University Ganzhou 341000, Jiangxi, China.
Objective: To investigate and analyze the clinical efficacy and safety of polymyxin B sulfate in the treatment of carbapenem-resistant gram-negative bacteria (CR-GNB) in sepsis; in order to provide reference for the clinical diagnosis, treatment and prognosis evaluation of sepsis.
Methods: The clinical data of 76 patients with CR-GNB sepsis treated with polymyxin B sulfate combined with an anti-infection regimen in the First Affiliated Hospital of Gannan Medical University from January 2020 to February 2024 were retrospectively studied. To analyze and discuss the clinical characteristics, results of the bacterial culture and drug sensitivity, clinical efficacy and prognosis of CR-GNB patients, efficacy comparison of different doses of polymyxin B sulfate treatment regimens, efficacy comparison of different combination regimens based on polymyxin B sulfate, changes in clinical indexes before and after treatment of polymyxin B sulfate, adverse drug reactions and adverse events of polymyxin B sulfate were investigated.
PeerJ
October 2024
Biology, University of Washington, Seattle, WA, United States of America.
The proportions of individuals in various age classes in a population of wild animals affect population trends, behaviors, learning, and social structures. Knowledge of age structure is needed for effective conservation and management of populations. However, it is not always possible to determine the age or age class of individual animals, and hence the age structure of the population.
View Article and Find Full Text PDFCureus
August 2024
College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Jeddah, SAU.
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