Overview of pyridine nucleotides review series

Pyridine nucleotides are abundant soluble coenzymes and they undergo reversible oxidation and reduction in several biological electron-transfer reactions. They are comprised of two mononucleotides, adenosine monophosphate and nicotinamide mononucleotide, and are present as oxidized and reduced nicotinamide adenine dinucleotides in their unphosphorylated (NAD(+) and NADH) and phosphorylated (NADP(+) and NADPH) forms. In the past, pyridine nucleotides were considered to be primarily electron-shuttling agents involved in supporting the activity of enzymes that catalyze oxidation-reduction reactions. However, it has recently been demonstrated that pyridine nucleotides and the balance between the oxidized and reduced forms play a wide variety of pivotal roles in cellular functions as important interfaces, beyond their coenzymatic activity. These include maintenance of redox status, cell survival and death, ion channel regulation, and cell signaling under normal and pathological conditions. Furthermore, targeting pyridine nucleotides could potentially provide therapeutically useful avenues for treating cardiovascular diseases. This review series will highlight the functional significance of pyridine nucleotides and underscore their physiological role in cardiovascular function and their clinical relevance to cardiovascular medicine.     

18F-Fluorodeoxyglucose-Positive Warthin Tumor in a Contralateral Cervical Lymph Node Mimicking Metastasis in Tongue Cancer Staging With PET/CT

ABSTRACT: We report F-fluorodeoxyglucose-positive Warthin tumor in a contralateral cervical lymph node mimicking metastasis in tongue cancer staging with positron emission tomography/computed tomography.     

State of intracortical inhibitory interneuron activity in patients with chronic stroke

ObjectivesFew studies have assessed short intracortical inhibition (SICI) in the affected hemisphere (AH) in a large number of patients with chronic stroke. In this study, SICI was assessed in chronic stroke patients with severe hemiparesis, and its relationship to clinical parameters was examined.MethodsThe participants were 72 patients with chronic hemiparetic stroke. SICI of both the AH and the unaffected hemisphere (UH) was assessed. The relationships between SICI and the location of lesion, time from onset, and finger function were studied. Motor function of the paretic finger was assessed with the Stroke Impairment Assessment Set (SIAS) and the Fugl-Meyer test upper extremity motor score. To compare the results with those of healthy subjects, SICI was assessed in seven age-matched control subjects.ResultsMEPs of the UH were evoked in all 72 subjects, and MEPs of the AH were evoked in 24 subjects. SICI of the AH was inversely correlated with paretic finger motor function and time from stroke onset. SICI of the UH was not correlated with either one. SICI of the UH was higher in the cortical lesion group than in the control group.ConclusionsThe state of intracortical inhibitory neuron activity depends on the state of motor function and lesion site even in chronic stroke patients with severe hemiparesis.SignificanceThe inhibitory system of the AH is involved in functional recovery of the paretic hand even in the chronic stage of stroke.