In a previous report we have shown that a few substances, especially thiouracil, are incorporated as false precursors into melanin during its synthesis. In the present investigation, we have intensified our studies on the incorporation of thiouracil into melanotic melanomas. Firstly, the distribution and retention of both 14C- and 35S-labelled thiouracil in mice with transplanted melanomas were studied. A high and selective accumulation was found in the melanotic tumours. The concentration in the rest of the body was low, with the exception of the thyroid gland. Secondly, melanoma-bearing mice were given increasing doses of thiouracil, and cultured melanoma cells were exposed to different concentrations of thiouracil, to investigate the relation between dose and uptake in melanomas and melanoma cells, respectively. A relatively linear increase in uptake with dose was found, indicating that the melanin incorporation of thiouracil is non-saturable up to subtoxic levels.
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http://dx.doi.org/10.1038/bjc.1982.12 | DOI Listing |
Nat Commun
January 2025
Frontiers Science Center for Molecular Design Breeding, Beijing Key Laboratory of Crop Genetic Improvement, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China.
During cold acclimation in high-latitude and high-altitude regions, japonica rice develops enhanced cold tolerance, but the underlying genetic basis remains unclear. Here, we identify CTB5, a homeodomain-leucine zipper (HD-Zip) transcription factor that confers cold tolerance at the booting stage in japonica rice. Four natural variations in the promoter and coding regions enhance cold response and transcriptional regulatory activity, enabling the favorable CTB5 allele to improve cold tolerance.
View Article and Find Full Text PDFBDJ Open
January 2025
Department of Orthodontics, Institute of Dentistry, Medical Faculty, Jagiellonian University, Kraków, Poland.
Background And Objectives: Gingivitis and periodontitis are common periodontal diseases that can significantly harm overall oral health, affecting the teeth and their supporting tissues, along with the surrounding anatomical structures, and if left untreated, leading to the total destruction of the alveolar bone and the connective tissues, tooth loss, and other more serious systemic health issues. Numerous studies have shown that propolis can help reduce gum inflammation, inhibit the growth of pathogenic bacteria, and promote tissue regeneration, but with varying degrees of success reported. For this reason, this comprehensive systematic review aims at finding out the truth concerning the efficacy of propolis mouthwashes in treating gingivitis and periodontitis, as its main objective.
View Article and Find Full Text PDFChemosphere
January 2025
Chemical and Veterinary Analytical Institute Muensterland-Emscher-Lippe, Joseph-König-Str. 40, 48147, Muenster, Germany.
Perfluorocarboxylic acids and perfluorosulfonic acids accumulate in food webs, thus posing a serious threat to food safety. The European Food Safety Authority (EFSA) derived a tolerable weekly intake (TWI) of 4.4 ng/kg body weight for the sum of the four so-called EFSA-PFAS in 2020.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
Infectious Diseases Laboratory, Campus Ministro Reis Velloso, Federal University of Parnaíba Delta, 64202-020 Parnaíba, PI, Brazil. Electronic address:
Visceral leishmaniasis is a systemic disease that affects various internal organs and represents the most severe and fatal form of leishmaniasis. Conventional treatment presents significant challenges, such as prolonged management in hospital settings, high toxicity, and an increasing growing number of cases of resistance. In previous studies, our research group demonstrated the effective and selective activity of the 2-amino-thiophene derivative SB-83 in preclinical models of cutaneous leishmaniasis.
View Article and Find Full Text PDFPoult Sci
January 2025
College of Animal Science, Zhejiang University, Hangzhou 310058, China. Electronic address:
The present study investigated the impact of butyrate glycerides (BG) on lipid metabolism, intestinal morphology, and microbiota of laying hens. Four hundred eighty 54-week-old Hy-line Brown laying hens were randomly selected and divided into five groups. The control group (ND) was fed a basal diet.
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