Distal Radiation Access as an Alternative to Conventional Radial Access for Coronary Angiography and Percutaneous Coronary Interventions (According to TENDERA Trial)

The aim of this study was to assess the immediate and medium-term (3 months) results of the safety and efficacy of distal radial access (DRA) in coronary interventions compared with conventional transradial radial access (TRA). TRA is the recommended access for coronary procedures because of increased safety: fewer local complications, large and small bleeding. Recently, DRA has emerged as a promising alternative access to minimize radial artery occlusion (RAO) risk, as well as other complications. A large-scale, international, randomized trial comparing medium-term results with TRA and DRA is lacking. An analysis of 776 patients of the prospective randomized TENDERA trial was carried out: the distal artery access group (DRA) - 391, the transradial access group (TRA) - 385. Statistically more often the crossover access was in the DRA group (5.1% and 0.8%, P < 0.001). The primary endpoint was early or late thrombosis/occlusion of the radial artery (RA). Secondary endpoints: (1) composite complications from access vessels; (2) access parameters. Statistically significant differences were obtained for the primary endpoint: DRA 2.7% (n = 10), TRA 6.8% (n = 26), P = 0.008. Occlusion of the distal radial artery (DRAt), with patent RA: DRA 1.3% (n = 5), TRA 0 (0), P = 0.023. At the secondary composite endpoint, statistically significant differences were obtained for the following groups of complications: BARC type I bleeding (DRA: 3.8% (n = 14), TRA: 21.7% (n = 83), P < 0.001); hematoma larger than 5 cm on day 1 (DRA: 10% [n = 37], TRA: 25.9% [n = 98], P < 0.001); hematoma larger than 5 cm on day 7 (DRA: 12.4% [n = 45], TRA: 34.6% [n = 132], P < 0.001). Of the access parameters, the following statistically significantly differed: puncture time DRA 19.0 (8.0; 50), TRA 13.5 (5.0; 29), P < 0.001; insertion of introducer DRA 42.0 (26.0; 84.0), TRA 35.0 (23.0; 55.0), P < 0.001, access artery hemostasis duration (min.) DRA 180.0 (120.0; 480.0), TRA 155.0 (115.0; 195.0), P < 0.001. The duration of the procedure and fluoroscopy, radiation dose, RA spasm in both groups had no statistically significant differences. In the TENDERA trail, DRA demonstrated efficacy and safety in interventional coronary interventions compared with TRA in the medium-term follow-up period: a statistically significant lower incidence of RA occlusion and local complications.

Testing Crack Resistance of Non-Load-Bearing Ceramic Walls with Door Openings

Cracking in non-load-bearing internal partition walls is a serious problem that frequently occurs in new buildings within the short term after putting them into service or even before completion of construction. Sometimes, it is so considerable that it cannot be accepted by the occupiers. The article presents tests of cracking in ceramic walls with a door opening connected in a rigid and flexible way along vertical edges. The first analyzes were conducted using the finite element method (FEM), and afterward, the measurements of deformations and stresses in walls on deflecting floors were performed on a full scale in the actual building structure. The measurements enabled to determine floor deformations leading to cracking of walls and to establish a dependency between the values of tensile stresses within the area of the door opening corners and their location along the length of walls and type of vertical connection with the structure.

Spin Fine Structure Reveals Biexciton Geometry in an Organic Semiconductor

In organic semiconductors, biexcitons are key intermediates in carrier multiplication and exciton annihilation. Their local geometry governs their electronic properties and yet has been challenging to determine. Here, we access the structure of the recently discovered S=2 quintet biexciton state in an organic semiconductor using broadband optically detected magnetic resonance. We correlate the experimentally extracted spin structure with the molecular crystal geometry to identify the specific molecular pairings on which biexciton states reside.

[IMMUNOLOGICAL AND NON-IMMUNOLOGICAL PATHOGENETIC MECHANISMS OF DEVELOPMENT OF COMPLICATED FORMS OF ATOPIC DERMATITIS (REVIEW)]

Difficult to control atopic dermatitis (AD) presents a therapeutic challenge and often requires combinations of topical and systemic treatment. Causes of severe AD are individual in each patient (e.g. genetic, barrier function, allergies). In this review, we will examine the highly complex interplay among skin barrier abnormality, allergy, immune dysregulation and antimicrobial peptide as a trinity in the development of AD. Studying of pathogenesis of formation of the complicated current the AD is a key problem of successful control as contamination of skin, and allergic inflammation.

Ca2+/calmodulin-kinase II enhances channel conductance of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate type glutamate receptors

The ability of central glutamatergic synapses to change their strength in response to the intensity of synaptic input, which occurs, for example, in long-term potentiation (LTP), is thought to provide a cellular basis for memory formation and learning. LTP in the CA1 field of the hippocampus requires activation of Ca2+/calmodulin-kinase II (CaM-KII), which phosphorylates Ser-831 in the GluR1 subunit of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate glutamate receptor (AMPA-R), and this activation/phosphorylation is thought to be a postsynaptic mechanism in LTP. In this study, we have identified a molecular mechanism by which CaM-KII potentiates AMPA-Rs. Coexpression in HEK-293 cells of activated CaM-KII with GluR1 did not affect the glutamate affinity of the receptor, the kinetics of desensitization and recovery, channel rectification, open probability, or gating. Single-channel recordings identified multiple conductance states for GluR1, and coexpression with CaM-KII or a mutation of Ser-831 to Asp increased the contribution of the higher conductance states. These results indicate that CaM-KII can mediate plasticity at glutamatergic synapses by increasing single-channel conductance of existing functional AMPA-Rs or by recruiting new high-conductance-state AMPA-Rs.

Identification of the Ca2+/calmodulin-dependent protein kinase II regulatory phosphorylation site in the alpha-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate-type glutamate receptor

Ca2+/CaM-dependent protein kinase II (CaM-KII) can phosphorylate and potentiate responses of alpha-amino3-hydroxyl-5-methyl-4-isoxazole-propionate-type glutamate receptors in a number of systems, and recent studies implicate this mechanism in long term potentiation, a cellular model of learning and memory. In this study we have identified this CaM-KII regulatory site using deletion and site-specific mutants of glutamate receptor 1 (GluR1). Only mutations affecting Ser831 altered the 32P peptide maps of GluR1 from HEK-293 cells co-expressing an activated CaM-KII. Likewise, when CaM-KII was infused into cells expressing GluR1, the Ser831 to Ala mutant failed to show potentiation of the GluR1 current. The Ser831 site is specific to GluR1, and CaM-KII did not phosphorylate or potentiate current in cells expressing GluR2, emphasizing the importance of the GluR1 subunit in this regulatory mechanism. Because Ser831 has previously been identified as a protein kinase C phosphorylation site (Roche, K. W., O'Brien, R. J., Mammen, A. L., Bernhardt, J., and Huganir, R. L. (1996) Neuron 16, 1179-1188), this raises the possibility of synergistic interactions between CaM-KII and protein kinase C in regulating synaptic plasticity.

Regulatory phosphorylation of AMPA-type glutamate receptors by CaM-KII during long-term potentiation

Long-term potentiation (LTP), a cellular model of learning and memory, requires calcium-dependent protein kinases. Induction of LTP increased the phosphorus-32 labeling of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors (AMPA-Rs), which mediate rapid excitatory synaptic transmission. This AMPA-R phosphorylation appeared to be catalyzed by Ca2+- and calmodulin-dependent protein kinase II (CaM-KII): (i) it correlated with the activation and autophosphorylation of CaM-KII, (ii) it was blocked by the CaM-KII inhibitor KN-62, and (iii) its phosphorus-32 peptide map was the same as that of GluR1 coexpressed with activated CaM-KII in HEK-293 cells. This covalent modulation of AMPA-Rs in LTP provides a postsynaptic molecular mechanism for synaptic plasticity.

ATP mediates fast synaptic transmission in mammalian neurons

In addition to its diverse functions inside cells, ATP can act at several types of cell-surface receptor. One of these (P2X-purinoceptor) is believed to be a ligand-gated cation channel. The presence of P2X receptors on autonomic, sensory and central neurons suggests that ATP might be released to act as a fast excitatory synaptic transmitter. Here we record excitatory synaptic potentials and currents from cultured coeliac ganglion neurons which are mimicked by ATP, blocked by the P2-purinoceptor antagonist suramin, desensitized by alpha,beta-methylene-ATP and unaffected by antagonists acting at nicotine, 5-hydroxytryptamine, N-methyl-D-aspartate (NMDA), non-NMDA glutamate, gamma-aminobutyric acid (GABA), noradrenaline or adenosine receptors. We conclude that ATP is the neurotransmitter at this neuroneuronal synapse.

5-HT3 receptors are membrane ion channels

The neurohormone 5-hydroxytryptamine (5HT or serotonin) exerts its effects by binding to several distinct receptors. One of these is the M-receptor of Gaddum and Picarelli, now called the 5-HT3 receptor, through which 5-HT acts to excite enteric neurons. Ligand-binding and functional studies have shown that the 5-HT3 receptor is widely distributed in peripheral and central nervous tissue and evidence suggests that the receptor might incorporate an ion channel permeable to cations. We now report the first recordings of currents through single ion channels activated by 5-HT3 receptors, in excised (outside-out) membrane patches from neurons of the guinea pig submucous plexus. Whereas application of acetylcholine activated predominantly a 40-pS channel, 5-HT caused unitary currents apparently through two channels of conductances of 15 and 9 pS, which were reversibly blocked by antagonists of the 5-HT3 receptor. Receptors for amine neurotransmitters, including 5-HT1 and 5-HT2, have previously been thought to transduce their effects through GTP-binding proteins: the direct demonstration that 5-HT3 receptors are ligand-gated ion channels implies a role for 5-HT, and perhaps other amines, as a 'fast' synaptic transmitter.