Adenosine A2A Receptor Binding Profile of Two Antagonists, ST1535 and KW6002: Consideration on the Presence of Atypical Adenosine A2A Binding Sites

Adenosine A2A receptors seem to exist in typical (more in striatum) and atypical (more in hippocampus and cortex) subtypes. In the present study, we investigated the affinity of two adenosine A2A receptor antagonists, ST1535 [2 butyl -9-methyl-8-(2H-1,2,3-triazol 2-yl)-9H-purin-6-xylamine] and KW6002 [(E)-1,3-diethyl-8-(3,4-dimethoxystyryl)-7-methyl-3,7-dihydro-1H-purine-2,6,dione] to the “typical” and “atypical” A2A binding sites. Affinity was determined by radioligand competition experiments in membranes from rat striatum and hippocampus. Displacement of the adenosine analog [3H]CGS21680 [2-p-(2-carboxyethyl)phenethyl-amino-5’-N-ethylcarbox-amidoadenosine] was evaluated in the absence or in the presence of either CSC [8-(3-chlorostyryl)-caffeine], an adenosine A2A antagonist that pharmacologically isolates atypical binding sites, or DPCPX (8-cyclopentyl-1,3-dipropylxanthine), an adenosine A1 receptor antagonist that pharmacologically isolates typical binding site. ZM241385 [84-(2-[7-amino-2-(2-furyl) [1,2,4]-triazol[2,3-a][1,3,5]triazin-5-yl amino]ethyl) phenol)] and SCH58261 [(5-amino-7-(β-phenylethyl)-2-(8-furyl)pyrazolo(4,3-e)-1,2,4-triazolo(1,5-c) pyrimidine], two other adenosine A2A receptor antagonists, which were reported to differently bind to atypical and typical A2A receptors, were used as reference compounds. ST1535, KW6002, ZM241385 and SCH58261 displaced [3H]CGS21680 with higher affinity in striatum than in hippocampus. In hippocampus, no typical adenosine A2A binding was detected, and ST1535 was the only compound that occupied atypical A2A adenosine receptors. Present data are explained in terms of heteromeric association among adenosine A2A, A2B and A1 receptors, rather than with the presence of atypical A2A receptor subtype

Identification of Placenta Growth Factor Determinants for Binding and Activation of Flt-1 Receptor

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Individual and Contextual Determinants of (mal)adjustment in College Students who Study Abroad

This study focuses on a sample of college students who study abroad and the individual and contextual factors that, interacting with each other, may affect their (mal)adjustment. Studying abroad is an immersive experience that could potentially bring great benefits for students’ careers and personal growth, but at the same time, without the right tools, can lead to the risk of students’ maladjustment. Self-efficacy in dealing with negative emotions and empathic self-efficacy were considered as individual factors, and an inclusive teaching environment was considered as the contextual factor necessary for promoting youths’ adjustment (prosocial behavior and academic performance) and for preventing maladjustment (internalizing and externalizing problems). American college students (169 mean Age = 20.59, SD = 1.59; 78% males) participated to this study. A path analysis model showed that: internalizing problems were negatively predicted by self-efficacy beliefs in dealing with negative emotions; externalizing problems were negatively predicted by self-efficacy in dealing with negative emotions; prosocial behavior was positively predicted by empathic self-efficacy, self-efficacy beliefs in dealing with negative emotions, and inclusive teaching; scholastic performance was positively predicted by inclusive teaching

Proficiency of real-time PCR detection of latent Monilinia spp. infection in nectarine flowers and fruit

Rapid and reliable detection of Monilinia latent infections is needed to prevent and control dispersion of Monilinia spp. in infected localities and non-infected countries. A fast multiplex quantitative real-time PCR method (qPCR) for the detection and identification of Monilinia spp. latent infections in blossoms and fruit of nectarine trees (Prunus persica var. nucipersica) was tested in an inter-laboratory trial. The test performance study involving five laboratories was conducted to validate the sensitivity and specificity of several real-time PCR platforms for the detection of low amounts of Monilinia DNA (latent infections), using a common protocol, and to identify possible difficulties when these tests were implemented by diagnostic laboratories or national reference centres. The method has two hydrolysis probes distinguishing between Monilinia fructicola and M. fructigena/M. laxa. Validation included test performance accuracy, analytical specificity and sensitivity, repeatability, and reproducibility, as defined by standard PM7/98 of the European Plant Protection Organization (EPPO). All qPCR platforms detected Monilinia latent infections and mycelium samples with both hydrolysis probes, and healthy flowers and fruit samples gave negative results. The method specificity was consistent between different laboratories, despite different equipment used, and there were no laboratories with z-scores in the unacceptable region. Monilinia fructicola latent infection samples were correctly detected by all laboratories, but some M. laxa samples were cross-detected as if they were M. fructicola. Monilinia laxa cross-detection could be compensated by including the allelic discrimination step in qPCR runs, which permitted differentiating between M. fructicola and M. laxa samples. The inter-laboratory comparison demonstrated the robustness of the developed method and confirmed in-house validation data. This method could be used to detect latent infections of Monilinia in asymptomatic nectarine fruit and flowers

Rapid molecular assay for the evaluation of clove essential oil antifungal activity against wheat common bunt

Common bunt of durum wheat (DW), Triticum turgidum L. ssp. durum (Desf.) Husn., is caused by the two closely related fungal species belonging to Tilletia genus (Tilletiales, Exobasidiomycetes, Ustilaginomycotina): Tilletia laevis Kühn (syn. T. foetida (Wallr.) Liro.) and T. caries (DC) Tul. (syn. T. tritici (Bjerk.) G. Winter). This is one of the most devastating diseases in wheat growing areas worldwide, causing considerable yield loss and reduction of wheat grains and flour quality. For these reasons, a fast, specific, sensitive, and cost-effective method for an early diagnosis of common bunt in wheat seedlings is urgent. Several molecular and serological methods were developed for diagnosis of common bunt in wheat seedlings but at late phenological stages (inflorescence) or based on conventional PCR amplification, with low sensitivity. In this study, a TaqMan Real Time PCR-based assay was developed for rapid diagnosis and quantification of T. laevis in young wheat seedlings, before tillering stage. This method, along with phenotypic analysis, was used to study conditions favoring pathogen infection and to evaluate the effectiveness of clove oil-based seed dressing in controlling the disease. The overall results showed that: i) the Real Time PCR assay was able to quantify T. laevis in young wheat seedlings after seed dressing by clove oil in different formulations, greatly reducing times of analysis. It showed high sensitivity, detecting up to 10 fg of pathogen DNA, specificity and robustness, allowing to directly analyze crude plant extracts and representing a useful tool to speed up the tests of genetic breeding for disease resistance; ii) temperature was a critical point for disease development when using wheat seeds contaminated by T. laevis spores; iii) at least one of the clove oil-based formulations tested was able to efficiently control wheat common bunt, suggesting that clove oil dressing could represent a promising tool for managing the disease, especially in sustainable farming

Intrasellar psammomatous meningioma: a case report and review of the literature

Intrasellar meningioma (IM) is a rare occurrence that is difficult to distinguish preoperatively from the most common non-functioning pituitary adenoma. Here we describe a case of psammomatous IM occurring in a 68-year-old woman, presented with visual defects. On magnetic resonance imaging (MRI) she was found to have an intrasellar mass with suprasellar extension that was approached with transsphenoidal surgery. Subtle radiological hints, namely dural tail sign, intralesional calcifications and a marked and homogenous early enhancement of IM on MRI after gadolinium administration, may aid clinicians in achieving an accurate pre-operative diagnosis and choosing the proper surgical approach. The clinical and neuroradiological features of IM described in the literature has been reviewed

A placental growth factor variant unable to recognize vascular endothelial growth factor (VEGF) receptor-1 inhibits VEGF-dependent tumor angiogenesis via heterodimerization

Angiogenesis is one of the crucial events for cancer development and growth. Two members of the vascular endothelial growth factor (VEGF) family, VEGF-A and placental growth factor (PlGF), which are able to heterodimerize if coexpressed in the same cell, are both required for pathologic angiogenesis. We have generated a PlGF1 variant, named PlGF1-DE in which the residues Asp72 and Glu73 were substituted with Ala, which is unable to bind and activate VEGF receptor-1 but is still able to heterodimerize with VEGF. Here, we show that overexpression in tumor cells by adenoviral delivery or stable transfection of PlGF1-DE variant significantly reduces the production of VEGF homodimer via heterodimerization, determining a strong inhibition of xenograft tumor growth and neoangiogenesis, as well as significant reduction of vessel lumen and stabilization, and monocyte-macrophage infiltration. Conversely, the overexpression of PlGF1wt, also reducing the VEGF homodimer production comparably with PlGF1-DE variant through the generation of VEGF/PlGF heterodimer, does not inhibit tumor growth and vessel density compared with controls but induces increase of vessel lumen, vessel stabilization, and monocyte-macrophage infiltration. The property of PlGF and VEGF-A to generate heterodimer represents a successful strategy to inhibit VEGF-dependent angiogenesis. The PlGF1-DE variant, and not PlGF1wt as previously reported, acts as a "dominant negative" of VEGF and is a new candidate for antiangiogenic gene therapy in cancer treatment