Molecular mechanisms that stabilize short term synaptic plasticity during presynaptic homeostatic plasticity.

Presynaptic homeostatic plasticity (PHP) compensates for impaired postsynaptic neurotransmitter receptor function through a rapid, persistent adjustment of neurotransmitter release, an effect that can exceed 200%. An unexplained property of PHP is the preservation of short-term plasticity (STP), thereby stabilizing activity-dependent synaptic information transfer. We demonstrate that the dramatic potentiation of presynaptic release during PHP is achieved while simultaneously maintaining a constant ratio of primed to super-primed synaptic vesicles, thereby preserving STP. Mechanistically, genetic, biochemical and electrophysiological evidence argue that a constant ratio of primed to super-primed synaptic vesicles is achieved by the concerted action of three proteins: Unc18, Syntaxin1A and RIM. Our data support a model based on the regulated availability of Unc18 at the presynaptic active zone, a process that is restrained by Syntaxin1A and facilitated by RIM. As such, regulated vesicle priming/super-priming enables PHP to stabilize both synaptic gain and the activity-dependent transfer of information at a synapse

Galanthus woronowii (amaryllidaceae)'nin antioksidan aktivitesi ve toplam fenolik içeriği

Plants have been used for medicinal purpose since ancient times. Due to the including bioactive secondary metabolites, plants have gained the great interest for drug discovery and development process. In this work, Galanthus woronowii was extracted with hexane, dichloromethane and ethyl acetate sequentially. After removing of the solvent by rotary evaporator, crude extracts were yielded. Antioxidant activity including 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3- ethylbenzothiazoline-6-sulphonic acid) (ABTS) and reducing power assays were executed on corresponding extracts. In addition, total phenolic content was presented. Ethyl acetate extract included the most phenolic compounds and also it revealed the most antioxidant activity. Hence, this plant could be considered as a promising antioxidant agent.Bitkiler eski çağlardan beri tıbbi amaçlarla kullanılmaktadır. İçerdikleri biyoaktif sekonder metabolitlerden dolayı, bitkiler ilaç keşfi ve gelişimi için oldukça fazla ilgi görmektedir. Bu çalışmada, Galanthus woronowii türüne ait bitki materyalleri sırasıyla hekzan, diklorometan ve etil asetat ile ekstrakte edilmiştir. Çözücü dönerli buharlaştırıcı ile uzaklaştırıldıktan sonra ham ekstraktlar elde edilmiştir. Ekstraktların DPPH serbest radikal giderme, ABTS radikal katyon giderme ve indirgeme gücü aktiviteleri değerlendirilmiştir. Ayrıca toplan fenolik içerik belirlenmiştir. Etil asetat ekstraktının en çok fenolik içerdiği ve en yüksek antioksidan aktivite gösterdiği belirlenmiştir. Bu nedenlerle, bu bitki ümit verici antioksidan ajan olarak kabul edilebilir

Galanthus krasnovii (amaryllidaceae)'nin toplam fenolik içeriği ile antioksidan kapasitenin değerlendirilmesi

Natural products have gained the great interest due to their broad spectrum of biological activities. Galanthus krasnovii was dried at shade then extracted with hexane, dichloromethane, and ethyl acetate successively. After removing of solvent by reduced pressure, crude extracts of each solvent were yielded. Antioxidant activity including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical cation and reducing power assays were carried out for each extract. Moreover, total phenolic content was determined. Total phenolic content of hexane-, dichloromethane-, and ethyl acetate extracts were found as 60.95 mg GAE/g extract, 71.90 GAE/g extract and 58.90 GAE/g extract respectively. Dichloromethane and ethyl acetate extract revealed the moderate antioxidant activity.Doğal ürünler geniş spektrumlu biyolojik aktivite göstermelerinden dolayı yoğun ilgi görmektedirler. Galanthus krasnovii gölgede kurutulduktan sonra sırasıyla hekzan, diklorometan ve etil asetat ile ekstrakte edildi. Düşük basınçta çözücü uzaklaştırıldıktan sonra her bir çözücünün ekstraktı elde edildi. Her bir ekstraktın, 1,1-difenil-2- pikralhidrazil(DPPH) radikal, 2,2'-azino-bis(3- etilbenzotiazolin-6- sülfirik asit) (ABTS) radikal katyon ve indirgeme gücü antioksidan çalışmaları gerçekleştirildi. Ayrıca, ekstraktların toplam fenolik içerikleri belirlendi. Hekzan-, diklorometan- ve etil asetat ekstraktlarının toplam fenolik içerikleri sırasıyla 60.95 mg GAE/g ekstrakt, 71.90 GAE/g ekstrakt ve 58.90 GAE/g ekstrakt olarak belirlendi. Diklorometan ve etil asetat ekstraktları orta derece aktivite gösterdi

MCTP is an ER-resident calcium sensor that stabilizes synaptic transmission and homeostatic plasticity.

Presynaptic homeostatic plasticity (PHP) controls synaptic transmission in organisms from Drosophila to human and is hypothesized to be relevant to the cause of human disease. However, the underlying molecular mechanisms of PHP are just emerging and direct disease associations remain obscure. In a forward genetic screen for mutations that block PHP we identified mctp (Multiple C2 Domain Proteins with Two Transmembrane Regions). Here we show that MCTP localizes to the membranes of the endoplasmic reticulum (ER) that elaborate throughout the soma, dendrites, axon and presynaptic terminal. Then, we demonstrate that MCTP functions downstream of presynaptic calcium influx with separable activities to stabilize baseline transmission, short-term release dynamics and PHP. Notably, PHP specifically requires the calcium coordinating residues in each of the three C2 domains of MCTP. Thus, we propose MCTP as a novel, ER-localized calcium sensor and a source of calcium-dependent feedback for the homeostatic stabilization of neurotransmission

Search and rescue organizations and national medical rescue teams (NMRT)

Afet, insanlar için fiziksel, ekonomik ve sosyal kayıplar doğuran, insanın normal yaşantısını ve eylemlerini durduran veya kesintiye uğratan olaya verilen genel bir isimdir. Afetlerin doğurduğu sonuçlara bakıldığında çok fazla can ve mal kaybına neden oldukları görülür. Kayıpların bir kısmı doğrudan hemen afet ile birlikte ortaya çıkarken bir kısmı ise belirli bir süre sonra ortaya çıkabilir. Afet esnasında ve sonrasında hızlı müdahale, insan hayatını kurtarmada son derece önemlidir. Dünya’da afet ve acil durumlara müdahale etmek amacıyla pek çok arama kurtarma örgütü kurulmuştur. Türkiye’deki arama kurtarma örgütlerinden biri olan Ulusal Medikal Kurtarma Ekipleri (UMKE), çok sayıda can kaybının yaşandığı 1999 depremi sonrasında, afete maruz kalmış kişilere doğru ve çabuk müdahale ederek, ölü ve yaralı sayısını kabul edilebilir rakamlara indirgemek amacıyla 2004 yılında kurulmuştur. UMKE ulusal ve uluslararası her tür afet ve olağandışı durumlarda afetzedelere medikal kurtarma yapmak amacıyla Sağlık Bakanlığı tarafından oluşturulan yönergeye göre çalışan gönüllü sağlık çalışanlarından oluşan ekiplerdir.Disaster is a generic name given to an event causing physical, economic and social losses for people and it stops or interrupts the normal life and actions of the people. When looking at the outcomes of disasters, it can be seen that they mostly cause loss of life and property. While some of these losses emerged immediately with the disaster, some may occur after a certain time. Rapid intervention in during and after disaster is extremely important to recovery of people’s life. Many search and rescue organizations were founded in the World in order to intervene to disasters and emergency situations. After the 1999 earthquake that caused a lot of casualties, National Medical Rescue Teams (NMRT), one of the search and rescue organizations of Turkey, was founded in 2004 for the purpose of reducing number of dead and wounded to an acceptable rate by doing accurate and quick intervention for people exposed to disasters. NMRT are teams made up of volunteer health personnel working according to the regulations created by Ministry of Health to provide medical rescue services to victims of disasters and emergencies of all kinds, both domestic and international

Synthesis, structural characterization and anticancer activity of 3- (3,5-dinitrobenzoyl)-1H-imidazolidine-2-thione

201-209The present study describes the synthesis, characterization and in vitro anticancer potential evaluation of a novel 3-(3,5-dinitrobenzoyl)-1H-imidazolidine-2-thione compound. In the first step, structure analysis of the compound has been elucidated by NMR and FT-IR techniques. Theoretical NMR, FT-IR spectra, HOMO and LUMO orbital energies and MEP analyses have been used to determine the activity of the molecule by Gaussian 09 package program using DFT techniques. Furthermore, docking calculations have been performed for the BRCA2 (PDB Code: 3EU7) active side to foresee the possible mechanism of action of the synthesized compound. In the second step of the study, the synthesized compound has been screened for its potential in vitro anticancer activity against MCF-7 human breast cancer cell line using the cell proliferation (XTT), apoptosis, cell cycle arrest and intracellular ROS production assays. The results of XTT test revealed significant dereases in MCF-7 cell viability with the 24h IC50 value of 7.57 μM. It has been also observed that treatment with the IC50 concentration of the compound can significantly induce apoptosis, intracellular ROS production and G2/M phase arrest in MCF-7 cells

The role of ITO resistivity on current spreading and leakage in InGaN/GaN light emitting diodes

The effect of a transparent ITO current spreading layer on electrical and light output properties of blue InGaN/GaN light emitting diodes (LEDs) is discussed. When finite conductivity of ITO is taken into account, unlike in previous models, the topology of LED die and contacts are shown to significantly affect current spreading and light output characteristics in top emitting devices. We propose an approach for calculating the current transfer length describing current spreading. We show that an inter-digitated electrode configuration with distance between the contact pad and the edge of p-n junction equal to transfer length in the current spreading ITO layer allows one to increase the optical area of LED chip, as compared to the physical area of the die, light output power, and therefore, the LED efficiency for a given current density. A detailed study of unpassivated LEDs also shows that current transfer lengths longer than the distance between the contact pad and the edge of p-n junction leads to increasing surface leakage that can only be remedied with proper passivation. © 2017 Elsevier Lt

Evaluation of three instrumentation techniques at the precision of apical stop and apical sealing of obturation

OBJECTIVE: The aim of this study was to investigate the ability of two NiTi rotary apical preparation techniques used with an electronic apex locator-integrated endodontic motor and a manual technique to create an apical stop at a predetermined level (0.5 mm short of the apical foramen) in teeth with disrupted apical constriction, and to evaluate microleakage following obturation in such prepared teeth. MATERIAL AND METHODS: 85 intact human mandibular permanent incisors with single root canal were accessed and the apical constriction was disrupted using a #25 K-file. The teeth were embedded in alginate and instrumented to #40 using rotary Lightspeed or S-Apex techniques or stainless-steel K-files. Distance between the apical foramen and the created apical stop was measured to an accuracy of 0.01 mm. In another set of instrumented teeth, root canals were obturated using gutta-percha and sealer, and leakage was tested at 1 week and 3 months using a fluid filtration device. RESULTS: All techniques performed slightly short of the predetermined level. Closest preparation to the predetermined level was with the manual technique and the farthest was with S-Apex. A significant difference was found between the performances of these two techniques (