Neutral proteoglycanase and other protease activity from cellular and CM fractions of monolayer-cultured rabbit articular chondrocytes were studied. The cellular fraction comprising soluble cytoplasmic enzymes possessed concentration-dependent elastase-like esterase activity and activity against trypsin and chymotrypsin synthetic substrates but had little caseinase activity. The 20% ammonium sulfate precipitate of CM possessed more neutral caseinase activity than the 60% ammonium sulfate precipitate and the bulk of activity against the synthetic substrates. Activity against bovine nasal septum PG was present in these fractions. Both the 20% and 60% ammonium sulfate fractions reduced the viscosity and the S of the PG substrate. This activity was incompletely inhibited by preincubation with either 5 mM o-phenanthroline or 10 mM EDTA, indicating that it was paritally metal-dependent. The activity in the cellular fraction was also partially inhibited by o-phenanthroline but more so by EDTA. These data indicate that chondrocytes synthesize and secrete into the culture medium neutral proteoglycanase(s) capable of initiating degradation of PG derived from the neutral pH cartilage matrix. The inhibitory profiles, together with recent evidence of enzymes with similar activity extracted from cartilage suggested that the proteoglycanase enzyme(s) may occur in multiple forms.
Download full-text PDF |
Source |
---|
Sci Rep
January 2025
School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology (IUST), P.O. Box 16844-13114, Tehran, Iran.
Surfactant chemistry can affect the phenolic foam (PF) properties by controlling the collision and combination of the created bubbles during foam production. The study was accomplished using two surfactant families, nonionic: polysorbate (Tween80) and anionic: sodium and ammonium lauryl sulfates (SLS30 and ALS70) and sodium laureth sulfate (SLES270) to manufacture PF foams. Tween80 and SLS30 resulted in foams with the lowest and highest densities, 20.
View Article and Find Full Text PDFEnviron Pollut
January 2025
College of Environmental Sciences and Engineering, Peking University, Beijing, China; State Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management, Center for Environment and Health, Peking University, Beijing, China.
Association between long-term exposure to ambient fine particulate matter (PM) and lung cancer incidence is well-documented. However, the role of different PM constituents [black carbon (BC), ammonium (NH), nitrate (NO), organic matter (OM), and inorganic sulfate (SO)] remain unclear. The study aimed to specify the associations between PM constituents and lung cancer incidence.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China. Electronic address:
Evidence on the association of long-term exposure to fine particular matter (PM) and its chemical constituents with the prognosis of oral cancer patients is limited. We identified 1673 oral cancer patients from 2011 to 2021 in Fujian, China. We evaluated annual average concentrations of PM and constituents, including nitrate, sulfate, ammonium, black carbon (BC), and organic matter (OM), using bilinear interpolation based on the patients' residential address.
View Article and Find Full Text PDFEnviron Health (Wash)
January 2025
Institute of Medical Technology, Peking University Health Science Center, Beijing 100191, China.
Several studies reported that nonsteroidal anti-inflammatory drug (NSAID) use could alleviate subclinical effects of short-term exposure to fine particulate matter (PM). However, whether chronic NSAID use could mitigate the long-term effects of PM and its components on population mortality has been unknown. Based on a national representative survey of 47,086 adults (2007-2010) with follow-up information on the primary cause of death (until 2017), we investigated the long-term associations of PM and its major components, including black carbon (BC), ammonium (NH ), nitrate (NO ), organic matter (OM), and sulfate (SO ), with all-cause and cause-specific mortality using the Cox proportional hazards model.
View Article and Find Full Text PDFBMC Microbiol
January 2025
Liver and Gastrointestinal Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Background: Microbial cholesterol oxidase (ChoX) has wide clinical and industrial applications; therefore, many efforts are being made to identify promising sources. This study aimed to isolate a novel ChoX-producing bacterial strain from whey samples.
Results: The most efficient strain was selected based on extracellular ChoX-producing ability and characterized as Escherichia fergusonii (E.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!