For the purified alkaline phosphatase from bone, the ability to catalyze a phosphate transfer reaction from p-nitrophenyl phosphate to two different hydroxy acceptor compounds, ethanolamine and glycerol, was established by identification of the formed phosphorylated products, phosphoethanolamine and glycerol 3-phosphate, respectively. In addition, a steady-state kinetic analysis of the hydrolysis of p-nitrophenyl phosphate in the presence of an added nucleophile, diethanolamine, gave rise to the proposal of a simple model for the kinetic mechanism of the enzyme. This mechanism includes a covalent phosphoryl enzyme intermediate, the dephosphorylation of which by water (k3) or a nucleophile (k4) is rate-determining. According to this model, in the presence of diethanolamine, k3 and k4 were determined to be 4.44 s-1 M-1 and 1000 s-1 M-1, respectively. Therefore, in vitro a suitable nucleophile, such as diethanolamine, seems to be a better phosphate acceptor than water. These results may suggest that alkaline phosphatase from bone could be well suited for catalyzing phosphate transfer reactions in vivo as well.
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http://dx.doi.org/10.1016/0167-4838(91)90283-6 | DOI Listing |
Arq Bras Cir Dig
January 2025
Santa Casa de Misericórdia de Porto Alegre - Porto Alegre (RS), Brazil.
Background: Cholangiocarcinoma (CCA) is a rare neoplasm, with high mortality, originating in the bile ducts. Its incidence is higher in Eastern countries due to the endemic prevalence of liver parasites. Factors such as metabolic syndrome, smoking, and pro-inflammatory conditions are also linked to the disease.
View Article and Find Full Text PDFBraz J Biol
January 2025
Universidade Federal da Grande Dourados - UFGD, Faculdade de Ciências Agrárias, Dourados, MS, Brasil.
The objective of this study was to evaluate the effects of three levels of lipids in the diet on growth, metabolism, and intestinal and hepatic histopathology in discus fish (Symphysodon aequifasciatus). Fish were stocked in quadruplicate in aquarium (50L) and were fed experimental diets containing three levels (3%, 10%, and 14%) of dietary lipids (LP). At the end of the trial, no significant differences in growth performance were observed.
View Article and Find Full Text PDFPLoS One
January 2025
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China.
Algal decomposition plays an important role in affecting phosphorus (P) release from sediments in eutrophic lakes under global warming. Yet how rising air temperature affect endogenous P release from sediments during the algal decomposition is poorly understood. In this study, effect of increasing air temperature on endogenous P release was investigated.
View Article and Find Full Text PDFAging (Albany NY)
January 2025
Department of Medicine, Division of Nephrology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 23142, Taiwan.
Introduction: Bone turnover markers reflected the bone remodeling process and bone health in clinical studies. Studies on variation of bone remodeling markers in different stage CKD were scant, and this study investigated the role of bedside intradialytic cycling in altering concentrations of bone-remodeling markers in patients with end-stage renal disease (ESRD).
Materials And Methods: Participants were segmented into four groups: a group with eGFR >60 ml/min/1.
Jpn J Clin Oncol
January 2025
Department of Urology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
Background: Dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (dd-MVAC) regimen has been established as a systemic chemotherapy for patients with urothelial carcinoma. However, it is rarely used in Japan owing to the challenges associated with managing the related adverse events. This study aimed to optimize the dd-MVAC protocol for Japanese patients.
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