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.

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.

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.

Postsynaptic protein phosphorylation and LTP.

Prolonged changes in synaptic strength, such as those that occur in LTP and LTD, are thought to contribute to learning and memory processes. These complex phenomena occur in diverse brain structures and use multiple, temporally staged and spatially resolved mechanisms, such as changes in neurotransmitter release, modulation of transmitter receptors, alterations in synaptic structure, and regulation of gene expression and protein synthesis. In the CA1 region of the hippocampus, the combined activation of SRC family tyrosine kinases, protein kinase A, protein kinase C and, in particular, Ca2+/calmodulin-dependent protein kinase II results in phosphorylation of glutamate-receptor-gated ion channels and the enhancement of subsequent postsynaptic current. Crosstalk between these complex biochemical pathways can account for most characteristics of early-phase LTP in this region.

Two modes of activity of nicotinic acetylcholine receptor channels in sympathetic neurons.

Spectral analysis of acetylcholine (ACh) noise was performed in voltage-clamped neurons of the isolated rabbit superior cervical ganglion at 34-37 degrees C and at membrane potential--80 mV. Two modes of activity were found in the ionic channels of nicotinic ACh receptors, with mean channel life-times of for fast-operating channels and for slow-operating channels. Excitatory postsynaptic current (EPSC) decays exponentially with a time constant which is very close to , indicating that the slow-operating channel activity determines the duration of EPSC. The mean value of conductance of single nicotinic ACh-receptor channel is 36 more or less 3 pS.

[The effect of radiation factors on cerebrovascular diseases in the region of northern Bukovina]. / Vplyv radiatsiïnykh chynnykiv na tserebrovaskuliarni zakhvoriuvannia v rehioni Pivnichnoï Bukovyny.

Correlation was studied between indices for prevalence and incidence of cerebrovascular diseases (CVD) and level of radioactive contamination in the region of northern Bukovina. As far as CVD formation, prevalence, and incidence rate is concerned, long-term exposure to small doses of ionizing radiation (cesium and strontium) makes for augmentation or lowering of CVD levels depending on their form, age, and place of residence of those having become victims of the Chernobyl accident.

[Embolization of the hepatic artery in the treatment of malignant tumors of the liver]. / Embolizatsiia pechenochnoi arterii v lechenii zlokachestvennykh opukholei pecheni.

The results of therapeutic hepatic artery embolization (HAE) in 25 patients with malignant unresectable tumors of the liver are discussed. The proximal segments of the hepatic artery were occluded by metal spirals. Thrombosis of the portal vein was accepted as an absolute contraindication for HAE, and a tumor involving more than 50% of the volume of the liver and chronic hepatic insufficiency were considered relative contraindications. After the intervention signs of subjective improvement were noted in 73.9% and signs of objective improvement in 65.2% of cases. The mortality after HAE was 4.2%. The obtained results are evidence of the efficacy of proximal HAE as a method for the treatment of inoperable malignant tumors of the liver.

[Methods of creating a lymphovenous anastomosis in the neck in the treatment of lymphostasis in liver cirrhosis]. / Sposoby formirovaniia limfovenoznogo anastomoza na shee po povodu limfostaza pri tsirroze pecheni.

Certain technical moments of forming lymphovenous anastomoses in patients with cirrhosis of the liver are described. An experience with 97 operations has shown that the technical means proposed allow postoperative complications to be avoided.

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.