Introduction: Ammonia in form of ammonium ions is toxic and could decrease the dissolved oxygen in water and endanger the aquatic life. The aim of this study is the removal of ammonium using oxidation and adsorption by catalytic ozonation and clinoptilolite zeolite, respectively. Methods: The research method is Experimental. First, optimal pH of ammonium adsorption on carbon catalyst (5 g/L), ...

BACKGROUND Sonic hedgehog (Shh) signaling regulates cell growth during embryonic development, tissue homeostasis and tumorigenesis. Concentration-dependent cellular responses to secreted Shh protein are essential for tissue patterning. Shh ligand is covalently modified by two lipid moieties, cholesterol and palmitate, and their hydrophobic properties are known to govern the cellular release and...

Transition-metal complexes bearing labile ligands can be difficult to isolate and study in solution because of unwanted dinucleation or ligand substitution reactions. Metal–organic frameworks (MOFs) provide a unique matrix that allows site isolation stabilization well-defined transition-metal may importance as moieties for gas adsorption catalysis. Herein we report the development an situ anion...

Activation of TLR7 and TLR9 by endogenous RNA- or DNA-containing ligands, respectively, is thought to contribute to the complicated pathophysiology of systemic lupus erythematosus (SLE). These ligands induce the release of type-I interferons by plasmacytoid dendritic cells and autoreactive antibodies by B-cells, both responses being key events in perpetuating SLE. We recently described the deve...

Physiological responses mediated by cell-surface receptors frequently adapt or "desensitize" (i.e., terminate despite persistent occupancy of receptors by ligand). Binding of ligands to the external domains of a wide variety of surface receptors induces covalent modification of their cytoplasmic domains. A mechanism is presented in which the variety of receptor states generated by ligand bindin...

Chemoselective ligation, including "click" chemistry, has found wide utility in general synthetic strategies and the specific modification of polymers and biomolecules. This has resulted in a number of applications of such approaches, particularly in the biomedical area, including diagnostic imaging and drug delivery. However, tools to chemoselectively decorate target molecules with multiple co...

The Hedgehog (Hh) signaling pathway plays critical roles in metazoan development and in cancer. How the Hh ligand is secreted and spreads to distant cells is unclear, given its covalent modification with a hydrophobic cholesterol molecule, which makes it stick to membranes. We demonstrate that Hh ligand secretion from vertebrate cells is accomplished via two distinct and synergistic cholesterol...