Artificial neural network in the discrimination of lung cancer based on infrared spectroscopy.

Given the increasing prevalence of lung cancer worldwide, an auxiliary diagnostic method is needed alongside the microscopic examination of biopsy samples, which is dependent on the skills and experience of pathologists. Thus, this study aimed to advance lung cancer diagnosis by developing five (5) artificial neural network (NN) models that can discriminate malignant from benign samples based on infrared spectral data of lung tumors (n = 122; 56 malignant, 66 benign). NNs were benchmarked with classical machine learning (CML) models.

Guanosine Anxiolytic-Like Effect Involves Adenosinergic and Glutamatergic Neurotransmitter Systems.

Accumulating evidences indicate that endogenous modulators of excitatory synapses in the mammalian brain are potential targets for treating neuropsychiatric disorders. Indeed, glutamatergic and adenosinergic neurotransmissions were recently highlighted as potential targets for developing innovative anxiolytic drugs. Accordingly, it has been shown that guanine-based purines are able to modulate both adenosinergic and glutamatergic systems in mammalian central nervous system.

Intranasal guanosine administration presents a wide therapeutic time window to reduce brain damage induced by permanent ischemia in rats.

In addition to its intracellular roles, the nucleoside guanosine (GUO) also has extracellular effects that identify it as a putative neuromodulator signaling molecule in the central nervous system. Indeed, GUO can modulate glutamatergic neurotransmission, and it can promote neuroprotective effects in animal models involving glutamate neurotoxicity, which is the case in brain ischemia. In the present study, we aimed to investigate a new in vivo GUO administration route (intranasal, IN) to determine putative improvement of GUO neuroprotective effects against an experimental model of permanent focal cerebral ischemia.

High phosphate serum levels correlate with the severity of experimental severe acute pancreatitis: insight into the purinergic system.

Objectives: Extracellular purines are a component of the systemic inflammatory response, and their levels are modulated by ectonucleotidases. In addition, nucleotide hydrolysis releases phosphate. We studied serum phosphate levels as a predictor of severity in acute pancreatitis (AP) and their correlation with extracellular purinergic metabolism.

The potential therapeutic effect of guanosine after cortical focal ischemia in rats.

Background And Purpose: Stroke is a devastating disease. Both excitotoxicity and oxidative stress play important roles in ischemic brain injury, along with harmful impacts on ischemic cerebral tissue. As guanosine plays an important neuroprotective role in the central nervous system, the purpose of this study was to evaluate the neuroprotective effects of guanosine and putative cerebral events following the onset of permanent focal cerebral ischemia.

Effects of chronic guanosine treatment on hippocampal damage and cognitive impairment of rats submitted to chronic cerebral hypoperfusion.

Chronic cerebral hypoperfusion contributes to a cognitive decline related to brain disorders. Its experimental model in rats is a permanent bilateral common carotid artery occlusion (2VO). Overstimulation of the glutamatergic system excitotoxicity due to brain energetic disturbance in 2VO animals seems to play a pivotal role as a mechanism of cerebral damage.

Endotoxin-induced effects on nucleotide catabolism in mouse kidney.

Extracellular adenosine 5'-triphosphate (ATP) acts as a proinflammatory mediator. Adenosine, the final product of ATP breakdown, is an anti-inflammatory compound, acting mainly on adenosine A(2A) receptors. Considering that the kidney is an organ strongly affected during systemic inflammatory responses and that ectonucleotidases are responsible for the control of extracellular nucleotide and nucleoside levels, we examined the endotoxin-induced effects on ectonucleotidases in kidney membranes of mice, and whether CGS-21680 hydrochloride (3-[4-[2-[[6-amino-9-[(2R,3R,4S,5S)-5-(ethylcarbamoyl)-3,4-dihydroxy-oxolan-2-yl]purin-2-yl]amino]ethyl]phenyl]propanoic acid), a selective adenosine A(2A) receptor agonist, antagonizes the lipopolysaccharide (LPS)-induced effects on nucleotide catabolism in kidney.

L-NAME-treatment alters ectonucleotidase activities in kidney membranes of rats.

Aims: To investigate the effect of N(omega)-Nitro-L-arginine methyl ester (l-NAME) treatment, known to induce a sustained elevation of blood pressure, on ectonucleotidase activities in kidney membranes of rats.

Main Methods: L-NAME (30 mg/kg/day) was administered to Wistar rats for 14 days in the drinking water. Enzyme activities were determined colorimetrically and their gene expression patterns were analyzed by semi-quantitative RT-PCR.

Neonatal morphine exposure alters E-NTPDase activity and gene expression pattern in spinal cord and cerebral cortex of rats.

The neonate opioid system has been frequently investigated, and studies have shown that exposure to drugs in early life can have implications for nervous system development. It has been proposed that adenosine is involved in opioid antinociception, and ATP is involved in central and peripheral mechanisms of nociception. Extracellular nucleotides can be hydrolyzed by E-NTPDases and ecto-5'nucleotidase, which present the functions of removing ATP and generating adenosine.

Intrastriatal injection of hypoxanthine alters striatal ectonucleotidase activities: a time-dependent effect.

The aim of this study was to investigate the effects of intrastriatal injection of hypoxanthine on ectonucleotidase (E-NTPDases and ecto-5'-nucleotidase) activities and expressions in the striatum of rats. The effect of pre-treatment with vitamins E and C on the effects elicited by this oxypurine on enzymatic activities and on thiobarbituric reactive substances (TBARS) was also investigated. The effect of pre-incubation with hypoxanthine on nucleotide hydrolysis in striatum homogenate was also determined.

Ectonucleotidase activities are altered in serum and platelets of L-NAME-treated rats.

It is well known that hypertension is closely associated to the development of vascular diseases and that the inhibition of nitric oxide biosynthesis by administration of Nomega-Nitro-L-arginine methyl ester hydrochloride(L-NAME) leads to arterial hypertension. In the vascular system, extracellular purines mediate several effects;thus, ADP is the most important platelet agonist and recruiting ag ent, while adenosine, an end product of nucleotide metabolism, is a vasodilator and inhibitor of platelet activation and recruitment. Members of several families of enzymes, known as ectonucleotidases, including E-NTPDases (ecto-nucleoside triphosphate diphosphohydrolase), E-NPP (ecto-nucleotide pyrophosphatase/phosphodiesterase) and 5'-nucleotidase are able to hydrolyze extracellular nucleotides until their respective nucleosides.