Extracellular purines have a role in renal physiology and adaption to inflammation. However, inflammatory renal disease may be mediated by extracellular purines, resulting in renal injury. The role of purinergic signaling is dependent on the concentrations of extracellular purines. Low basal levels of purines are important in normal homeostasis and growth. Concentrations of extracellular purine...

Vaccines for counteracting inhibition of neutrophil degranulation by pathogenic cellular microorganisms comprise one or more purines conjugated to antigenic carriers. The purines include adenine and/or guanine in the form of a base, nucleoside, or nucleotide. The vaccines can be used with cattle to increase resistance to infections by Brucella abortus (brucellosis) and/or Haemophilus somnus (th...

On the basis of our study on the structure-activity relationships of 1,3,7-alkylxanthines and condensed-purines on cAMP-phosphodiesterase 4 (PDE 4) isoenzyme inhibitor, we investigated the synthesis and the inhibitory activity of 3-phenylxanthine and 4-phenyl[i]condensed-purine derivatives. Xanthines and condensed-purines with the phenyl group exhibited potent and selective PDE 4 inhibitory act...

Purinergic signalling regulates airway defence mechanisms, suggesting that extracellular purines could serve as airway inflammation biomarkers in cystic fibrosis (CF). The purines adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP) and adenosine were measured in sputum from 21 adults (spontaneously expectorated from seven CF patients, induced from 14 healthy...

In a previous publication (1) a procedure for paper chromatographic separation of xanthines and uric acids was described, which may serve as the prerequisite for quantitative determination of these compounds in biological fluids. Application of the procedure to plasma has been presented in a previous article (2). When the method was applied to urine, it became apparent that contaminating substa...

Purine is a ubiquitous heterocyclic scaffold of fundamental importance, and is considered to be a privileged structure in medicinal chemistry. Purine-based compounds, including N-aryl purines, exhibit a wide range of biological and pharmaceutical activities, such as antiviral, antibacterial and anticancer effects. In light of their importance, there is a surprising paucity of efficient methods ...

Tumors derive their nutrients from the host. These materials may come directly from the diet via the blood, from labile pools which may exist in host tissues, or from the substance of host tissues through their breakdown and transport to the tumor. This has been well studied in the case of tumor-host protein relationships and has resulted in the concept of the tumor as a nitrogen trap, since it...

P2X and P2Y nucleotide receptors are described on sensory neurons and their peripheral and central terminals in dorsal root, nodose, trigeminal, petrosal, retinal and enteric ganglia. Peripheral terminals are activated by ATP released from local cells by mechanical deformation, hypoxia or various local agents in the carotid body, lung, gut, bladder, inner ear, eye, nasal organ, taste buds, skin...

GAR transformylase, which is responsible for the incorporation of formate carbon into what becomes position 8 of the purine ring, has been completely separated from 5-amino-4-imidazolecarboxamide ribotide transformylase (3). The latter enzyme is responsible for the incorporation of formate carbon into position 2 of the purine ring. The requirement for folic acid compounds has been demonstrated ...

Certain purines, notably adenine, are readily incorporated into the nucleic acids of rat tissues (1). Studies with glycine, a specific precursor involved in the synthesis of purines, in the same animal have shown (2, 3) relative uptakes in the ribose nucleic acid (RNA) and deoxyribose nucleic acid (DNA) fractions which are somewhat different from those obtained with adenine (4). A simultaneous ...