Rat liver and brain differ in the distribution pattern of the total hydrolytic activity on diadenosine 5',5"'-P1,P3-triphosphate (Ap3A) between the soluble and particulate fractions. The Ap3A-hydrolase activity in both the soluble and particulate liver fractions and in the brain soluble fraction had been previously studied in detail. We report now on the brain particulate fraction which, unlike liver, showed a low unspecific phosphodiesterase I-like (PDEaseI, EC 3.1.4.1) activity relative to the specific dinucleoside triphosphatase (Ap3Aase, EC 3.6.1.29). Two PDEaseI-like forms (PDEaseI-A and PDEaseI-B), with different apparent Mrs and kinetic properties, and two Ap3Aases (Ap3Aase-alpha and Ap3Aase-beta) were solubilized with 0.5% Triton X-100 from the particulate fraction. Ap3Aase-alpha resembled the cytosolic Ap3Aase (Ap3Aase-c), a known situation in liver. Comparative to Ap3Aase-alpha, Ap3Aase-beta showed a slightly higher Km (35 vs. 15 micron) and lower isoelectric point (5.25 vs. 5.45); Ap3Aase-beta was absent from the soluble fraction, and its recovery was unaffected by proteinase inhibitors, strongly arguing for distinct soluble and particulate turnover pathways for dinucleoside polyphosphates.
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http://dx.doi.org/10.1016/0304-4165(91)90149-b | DOI Listing |
J Hazard Mater
January 2025
Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India.
Experiments were conducted in controlled laboratory conditions to determine the size-resolved CCN (Cloud Condensation Nuclei) activity of sub micrometer-sized aerosols containing nuclear fission products (CsI and CsOH) and abundant ambient inorganic aerosols ammonium sulphates ((NH)SO), ammonium chloride (NHCl), sodium nitrate (NaNO), and sodium chloride (NaCl). The presence of these atmospheric-relevant compounds internally mixed with fission product compounds has the potential to affect the capacity of ambient particulates of aerosols to absorb water and function as CCN. Once in the atmosphere, the dynamics of airborne radionuclides and subsequently their fate gets affected by dry and wet deposition processes.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
Migration characteristics and occurrence forms of redox-sensitive metal(loid)s such as arsenic (As), chromium (Cr), and vanadium (V) remained unclear in dynamic estuarine waters. In this work, size fractionation and chemical speciation of As, Cr, and V in the Jiaomen Waterway (JMW), a tidal river of the Pearl River estuary, were explored based on (ultra)filtration, the diffusive gradients in thin films (DGT) techniques and a thermodynamic chemical equilibrium model. The results showed that As was present mainly in soluble forms in the river water, and the suspended particulate matter (SPM) was identified the major carrier for Cr.
View Article and Find Full Text PDFBioresour Technol
January 2025
Department of Environmental Technologies, Faculty of Marine and Environmental Sciences, IVAGRO-Wine and Agrifood Research Institute, University of Cadiz, 11510 Puerto Real, Cadiz, Spain.
This study investigates the effects of ozone pre-treatment on two types of organic wastes: secondary sludge (SS) and wine vinasse (WV). Ozone pre-treatment of SS, a semi-solid waste, significantly increased the Dissolved Organic Carbon (DOC) and Total Volatile Fatty Acids (TVFAs) through hydrolysis. Conversely, ozone pre-treatment of WV, a liquid organic waste, reduced the availability of soluble biodegradable substrates and decreased the concentration of carboxylic acids with carbon chain length higher than 4.
View Article and Find Full Text PDFSci Rep
January 2025
Faculty of Computers and Information, Minia University, Minia, Egypt.
This paper proposes a hybridized model for air quality forecasting that combines the Support Vector Regression (SVR) method with Harris Hawks Optimization (HHO) called (HHO-SVR). The proposed HHO-SVR model utilizes five datasets from the environmental protection agency's Downscaler Model (DS) to predict Particulate Matter ([Formula: see text]) levels. In order to assess the efficacy of the suggested HHO-SVR forecasting model, we employ metrics such as Mean Absolute Percentage Error (MAPE), Average, Standard Deviation (SD), Best Fit, Worst Fit, and CPU time.
View Article and Find Full Text PDFChemosphere
January 2025
College of Design and Engineering, National University of Singapore, Singapore, 117576, Singapore. Electronic address:
Airborne particulate matter (PM) poses significant environmental and health challenges, particularly in urban areas. This study investigated the characteristics of water-soluble organic compounds (WSOC) in PM (PM with an aerodynamic diameter of 2.5 μm or less) in Singapore, a tropical Asian city-state, over a six-month period.
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