Signaling through the cyclic adenosine monophosphate-dependent protein kinase [protein kinase A (PKA)] is an important and widely studied area of signal transduction research. This signaling pathway is commonly investigated through the use of the pharmacological PKA inhibitors H89 and KT 5720. Both of these compounds are thought to block PKA actions through competitive inhibition of the adenosi...

A 54-year-old Spanish woman sought medical advice at the outpatient clinic of our institution for diarrhoea and abdominal pain that began on her return from Cambodia and Laos ten days earlier. On examination, she had neither fever nor skin lesions. Laboratory tests showed haemoglobin, hepatic enzymes and a leucocyte count within normal range. No eosinophilia was detected. The patient was diagno...

The classic hepatotropic viruses, hepatitis A through E, are not the only viral agents able to infect the liver. Other systemic viruses may cause hepatic injury that can range from mild and transient elevation of aminotransferases to acute hepatitis and occasionally acute liver failure and fulminant hepatitis. The clinical presentation may be indistinguishable from that associated with classic ...

A 34-year-old male with diabetes presented to the emergency department with four days of progressively worsening redness, swelling and pain to his left buttock. The patient denied fevers, chills, rectal pain or purulent drainage from his rectum. His initial vital signs were heart rate of 82; blood pressure of 146/92; and temperature of 98.2°F. The left buttock had a poorly circumscribed area of...

Anemia in the elderly is a common but challenging clinical scenario. Here we describe the case of an older woman who presented with anemia and elevated inflammation markers. After a complete diagnostic work-up, a definite etiology of the anemia could not be found so eventually a bone marrow biopsy was performed and she was diagnosed with myelodysplastic syndrome. She responded well to erythropo...

Page 1 Overview of cAMP Signaling The transduction of extracellular signals to intracellular responses is one of the most important and complicated aspects of cellular life. The cyclic adenosine monophosphate (cAMP) signaling pathway is involved in numerous processes and is widely regarded as the “classical” second messenger signaling pathway. cAMP is synthesized from adenosine triphosphate (AT...