Tumorâ Selective Altered Glycosylation and Functional Attenuation of CD73 in Human Hepatocellular Carcinoma

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151913/1/hep41410_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151913/2/hep41410.pd

Activity-Dependent Shedding of the NMDA Receptor Glycine Binding Site by Matrix Metalloproteinase 3: A PUTATIVE Mechanism of Postsynaptic Plasticity

Functional and structural alterations of clustered postsynaptic ligand gated ion channels in neuronal cells are thought to contribute to synaptic plasticity and memory formation in the human brain. Here, we describe a novel molecular mechanism for structural alterations of NR1 subunits of the NMDA receptor. In cultured rat spinal cord neurons, chronic NMDA receptor stimulation induces disappearance of extracellular epitopes of NMDA receptor NR1 subunits, which was prevented by inhibiting matrix metalloproteinases (MMPs). Immunoblotting revealed the digestion of solubilized NR1 subunits by MMP-3 and identified a fragment of about 60 kDa as MMPs-activity-dependent cleavage product of the NR1 subunit in cultured neurons. The expression of MMP-3 in the spinal cord culture was shown by immunoblotting and immunofluorescence microscopy. Recombinant NR1 glycine binding protein was used to identify MMP-3 cleavage sites within the extracellular S1 and S2-domains. N-terminal sequencing and site-directed mutagenesis revealed S542 and L790 as two putative major MMP-3 cleavage sites of the NR1 subunit. In conclusion, our data indicate that MMPs, and in particular MMP-3, are involved in the activity dependent alteration of NMDA receptor structure at postsynaptic membrane specializations in the CNS

Regional mechanical and biochemical properties of the porcine cortical meninges

peer-reviewedThe meninges are pivotal in protecting the brain against traumatic brain injury (TBI), an ongoing issue in most mainstream sports. Improved understanding of TBI biomechanics and pathophysiology is desirable to improve preventative measures, such as protective helmets, and advance our TBI diagnostic/prognostic capabilities. This study mechanically characterised the porcine meninges by performing uniaxial tensile testing on the dura mater (DM) tissue adjacent to the frontal, parietal, temporal, and occipital lobes of the cerebellum and superior sagittal sinus region of the DM. Mechanical characterisation revealed a significantly higher elastic modulus for the superior sagittal sinus region when compared to other regions in the DM. The superior sagittal sinus and parietal regions of the DM also displayed local mechanical anisotropy. Further, fatigue was noted in the DM following ten preconditioning cycles, which could have important implications in the context of repetitive TBI. To further understand differences in regional mechanical properties, regional variations in protein content (collagen I, collagen III, fibronectin and elastin) were examined by immunoblot analysis. The superior sagittal sinus was found to have significantly higher collagen I, elastin, and fibronectin content. The frontal region was also identified to have significantly higher collagen I and fibronectin content while the temporal region had increased elastin and fibronectin content. Regional differences in the mechanical and biochemical properties along with regional tissue thickness differences within the DM reveal that the tissue is a non-homogeneous structure. In particular, the potentially influential role of the superior sagittal sinus in TBI biomechanics warrants further investigation

Prenatal Cocaine Exposure Increases Synaptic Localization of a Neuronal RasGEF, GRASP-1 via Hyperphosphorylation of AMPAR Anchoring Protein, GRIP

Prenatal cocaine exposure causes sustained phosphorylation of the synaptic anchoring protein, glutamate receptor interacting protein (GRIP1/2), preventing synaptic targeting of the GluR2/3-containing alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type glutamate receptors (AMPARs; J. Neurosci. 29: 6308–6319, 2009). Because overexpression of GRIP-associated neuronal rasGEF protein (GRASP-1) specifically reduces the synaptic targeting of AMPARs, we hypothesized that prenatal cocaine exposure enhances GRASP-1 synaptic membrane localization leading to hyper-activation of ras family proteins and heightened actin polymerization. Our results show a markedly increased GRIP1-associated GRASP-1 content with approximately 40% reduction in its rasGEF activity in frontal cortices (FCX) of 21-day-old (P21) prenatal cocaine-exposed rats. This cocaine effect is the result of a persistent protein kinase C (PKC)- and downstream Src tyrosine kinase-mediated GRIP phosphorylation. The hyperactivated PKC also increased membrane-associated GRASP-1 and activated small G-proteins RhoA, cdc42/Rac1 and Rap1 as well as filamentous actin (F-actin) levels without an effect on the phosphorylation state of actin. Since increased F-actin facilitates protein transport, our results suggest that increased GRASP-1 synaptic localization in prenatal cocaine-exposed brains is an adaptive response to restoring the synaptic expression of AMPA-GluR2/3. Our earlier data demonstrated that persistent PKC-mediated GRIP phosphorylation reduces GluR2/3 synaptic targeting in prenatal cocaine-exposed brains, we now show that the increased GRIP-associated GRASP-1 may contribute to the reduction in GluR2/3 synaptic expression and AMPAR signaling defects

A UNITARY APPROACH TO SOME CLASSICAL INEQUALITIES

Abstract. In this paper, we will give a unitary approach to some classical inequalities. We will show that these results could be proved in the same manner

Oral Candidiasis and Inflammatory Response: a Potential Synergic Contribution to the Onset of Type-2 Diabetes Mellitus

It is known that fungal pathogens activate cellular immune responses involving several inflammatory molecules. On the other hands, it is well known that diabetic patients show a chronic inflammatory state. In this study, we explore the hypothesis that yeast colonization of the oral cavity directly influences the tendency of an individual to develop type 2 Diabetes. According to this hypothesis, oral yeast colonization may influence the pathway in which the immune response handles subsequent responses to glucose intake. The first part of this work presents data concerning oral Candida carriage in subjects with pre-diabetes, the second part explores the potential role of oral Candida infection, related to inflammatory response in promoting insulin resistance

Two cases of combined anatomical variations: maxillofacial trunk, vertebral, posterior communicating and anterior cerebral atresia, linguofacial and labiomental trunks

Background: Commonly, arterial anatomic variants are reported as single entities. However, different such variants can occur in a single patient. Materials and methods: During a retrospective study of computed tomography angiograms of 52 adult patients, two cases were found with unilateral maxillofacial trunks. In each case different other anatomic variants were documented. Results: The maxillofacial trunk in the first case was associated with bilateral posterior kinks of the internal carotid artery which passed beyond the transverse processes of the atlas vertebra and indented and displaced the internal jugular veins. Common carotid origins of the superior thyroid arteries were found, as well as a high origin of the contralateral facial artery. In the second case a plethora of variants were associated with a unilateral maxillofacial trunk: (1) direct occipital-vertebral arterial anastomosis; (2) ipsilateral atresia of the distal vertebral artery and of the A1 segment of the anterior cerebral artery; (3) bilateral atresia of posterior communicating arteries; (4) linguofacial and labiomental trunks; (5) terminal trifurcation of the external carotid artery. Conclusions: The arterial anatomical variants of the head and neck should be carefully documented prior to specific surgical and interventional procedures, as well as for understanding the compensatory anatomical pathways of circulatory insufficiencies

The Pharmacological Treatment of Chronic Pain: From Guidelines to Daily Clinical Practice

In agreement with the International Association for the Study of Pain, chronic pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. To date, there are several types of pain: nociceptive, neuropathic, and nociplastic. In the present narrative review, we evaluated the characteristics of the drugs used for each type of pain, according to guidelines, and their effects in people with comorbidity to reduce the development of severe adverse events