Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Search Results: 1 - 10 of 2308 matches for " Irina Madorsky "
All listed articles are free for downloading (OA Articles)
Page 1 /2308
Display every page Item
Activation of Phospholipase C Mimics the Phase Shifting Effects of Light on Melatonin Rhythms in Retinal Photoreceptors
Susan Semple-Rowland, Irina Madorsky, Susan Bolch, Jonathan Berry, W. Clay Smith
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0083378
Abstract: Many aspects of retinal photoreceptor function and physiology are regulated by the circadian clocks in these cells. It is well established that light is the primary stimulus that entrains these clocks; yet, the biochemical cascade(s) mediating light’s effects on these clocks remains unknown. This deficiency represents a significant gap in our fundamental understanding of photoreceptor signaling cascades and their functions. In this study, we utilized re-aggregated spheroid cultures prepared from embryonic chick retina to determine if activation of phospholipase C in photoreceptors in the absence of light can phase shift the melatonin secretion rhythms of these cells in a manner similar to that induced by light. We show that spheroid cultures rhythmically secrete melatonin and that these melatonin rhythms can be dynamically phase shifted by exposing the cultures to an appropriately timed light pulse. Importantly, we show that activation of phospholipase C using m-3M3FBS in the absence of light induces a phase delay in photoreceptor melatonin rhythms that mirrors that induced by light. The implication of this finding is that the light signaling cascade that entrains photoreceptor melatonin rhythms involves activation of phospholipase C.
Bicistronic Lentiviruses Containing a Viral 2A Cleavage Sequence Reliably Co-Express Two Proteins and Restore Vision to an Animal Model of LCA1
Jonathan D. Verrier, Irina Madorsky, William E. Coggin, Mero Geesey, Michael Hochman, Elleanor Walling, Daniel Daroszewski, Kristofer S. Eccles, Rachel Ludlow, Susan L. Semple-Rowland
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0020553
Abstract: The disease processes underlying inherited retinal disease are complex and are not completely understood. Many of the corrective gene therapies designed to treat diseases linked to mutations in genes specifically expressed in photoreceptor cells restore function to these cells but fail to stop progression of the disease. There is growing consensus that effective treatments for these diseases will require delivery of multiple therapeutic proteins that will be selected to treat specific aspects of the disease process. The purpose of this study was to design a lentiviral transgene that reliably expresses all of the proteins it encodes and does so in a consistent manner among infected cells. We show, using both in vitro and in vivo analyses, that bicistronic lentiviral transgenes encoding two fluorescent proteins fused to a viral 2A-like cleavage peptide meet these expression criteria. To determine if this transgene design is suitable for therapeutic applications, we replaced one of the fluorescent protein genes with the gene encoding guanylate cyclase -1 (GC1) and delivered lentivirus carrying this transgene to the retinas of the GUCY1*B avian model of Leber congenital amaurosis – 1 (LCA1). GUCY1*B chickens carry a null mutation in the GC1 gene that disrupts photoreceptor function and causes blindness at hatching, a phenotype that closely matches that observed in humans with LCA1. We found that treatment of these animals with the 2A lentivector encoding GC1 restored vision to these animals as evidenced by the presence of optokinetic reflexes. We conclude that 2A-like peptides, with proper optimization, can be successfully incorporated into therapeutic vectors designed to deliver multiple proteins to neural retinal. These results highlight the potential of this vector design to serve as a platform for the development of combination therapies designed to enhance or prolong the benefits of corrective gene therapies.
TAXODIUM Version 1.0: A Simple Way to Generate Uniform and Fractionally Weighted Three-Item Matrices from Various Kinds of Biological Data
Evgeny V. Mavrodiev, Alexander Madorsky
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048813
Abstract: An open-access program for generating three-item statement (3TS) matrices from data such as molecular sequences does not currently exist. The recently developed LisBeth package allows for representation of hypotheses of homology among taxa or areas directly as rooted trees or as hierarchies; however, LisBeth is not a standard matrix-based platform. Here we present “TAXODIUM version 1.0” (TAXODIUM), a program designed for building 3TS-matrices from binary, additive (ordered) and non-additive (unordered) multistate characters, with both uniform and fractional weighting of the statements. TAXODIUM also facilitates, for the first time, use of Maximum Likelihood analyses with 3TS matrices, but future implementation of the 3TS analysis in a statistical framework will require more exploration.
Application of prodigiosin as a colorant for polyolefines  [PDF]
Irina Ryazantseva, Irina Andreyeva
Advances in Biological Chemistry (ABC) , 2014, DOI: 10.4236/abc.2014.41004
Abstract: Serratia marcescens strain 9986 is a producer of prodigiosin used as a dye of polyolefines (polyethylene, ultratene). The biosynthesis of pigment was closely connected with controlled growth parameters. A prodigiosin yield 0.2 - 0.4 mg per l of culture medium in the batch culture under aerobic conditions was obtained. Prodigiosin was extracted from crude biomass treated by 0.1% of sodium dodecyl sulfate (SDS). This novel elaborated stage is necessary for thermostability a dye in polymer. The consumption of prodigiosin preparation is more economical in the technology of the coloration of polyolefines. The elaborated method has been manufactured for dyeing polyethylene by biological pigment-articles of the common use corresponding to the technological standard.
The Main Difficulties When Studying Russian Verbs of Motion in a Figurative Meaning  [PDF]
Irina Skripnikova
Open Journal of Modern Linguistics (OJML) , 2012, DOI: 10.4236/ojml.2012.24019
Abstract: Russian language acquisition requires deep and intensive studying of the concept of verbs of motion. There is a strong opinion that verbs of motion are one of the hardest concepts in the Russian language. However, it is an important issue, as motion verbs are among the most used in any language and nowadays there are hundreds of expressions with these verbs which can be heard quite frequently in the Russian language. Needless to say that mastering these verbs is even harder when they have figurative meaning. Therefore, the purpose of this paper is to demonstrate the importance of studying the figurative meanings of Russian verbs of motion and to prove that the process of teaching students these verbs is more efficient when they are compared with their English equivalents.
Preventative Strategies in the Management of ROP: A Review of Literature  [PDF]
Irina Livshitz
Open Journal of Pediatrics (OJPed) , 2015, DOI: 10.4236/ojped.2015.52018

Retinopathy of prematurity (ROP) is a potentially blinding eye disorder that primarily affects premature infants weighing 1250 grams or less that are born before 31 weeks of gestation. It is one of the most common causes of visual loss in childhood and can lead to lifelong vision impairment and blindness. Certain strategies for prevention have been confirmed by numerous trials, namely the role of oxygen therapy as an independent risk factor for the development of ROP and the benefits of strict control of premature infant oxygen saturations in the NICU. There is valuable data that supports use of other approaches, such as beta adrenergic blockade and IGF-1 supplementation, for which clinical trials are still in the works to establish clear protocols for their clinical use. Supplementation with vitamin A, omega-3 fatty acids, and inositol are all exciting arenas for further trials as preliminary data shows promising results in ROP prevention. It has also been shown that the benefit of vitamin E is not worth the increased incidence of NEC and sepsis as potential side effects. Furthermore, while it was an interesting idea to use the chelator D-penicillamine as a preventative strategy for ROP, the results of multiple trials seemed to be equivocal. This brief review is not all-inclusive, as there are many more modes of prevention currently being studied.

Principles of the analysis of structure of chaffinch song (Fringilla coelebs L.). Individual variability of song  [PDF]
Olesya Astakhova, Irina Byome
Open Journal of Animal Sciences (OJAS) , 2012, DOI: 10.4236/ojas.2012.23026
Abstract: Song of birds is subtle and flexible species specific feature, like as the morphology signs. Species specific song of chaffinch (Fringilla coelebs L.) can be judged as precise character in the image on sonograms. The song has the certain structure and shares (divides) on the parts, elements, which consists of them. Individual variability of songs of one type will consist in unique singing each of chaffinch males, who form a local population.
Induction Heating in the Processing of Ti & Zr  [PDF]
Victor Demidovich, Irina Rastvorova
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2014, DOI: 10.4236/jemaa.2014.613042
Abstract: Induction heating has important applications in science and industry. The method of induction heating can be successfully used for melting and heat treatment of titanium and zirconium alloys. Different applications using induction precise heating before plastic deformation are discussed in this paper. For alloys of many metals such as titanium, zirconium, niobium, tantalum, etc., it is important to provide precision heating with a high degree of homogeneity of the temperature field and strict adherence to the condition of heating. This is explained by polymorphism of the alloys based on these metals, their chemical activity at high temperatures and the specific thermal and electrical properties. It is very important for induction heating to define the extreme achievable unevenness of the temperature field. For special alloys it is necessary to use resistance furnaces for homogenization of billets’ temperature after heating in the inductors. Optimal control can be used for massive billets to reduce significantly the heating time, energy expenses and to improve the quality of the temperature field distribution. Optimization of induction heating process can be achieved by synchronous solution of the problem of optimal control and design with specially developed models.
Risk Modelling of Organic Pollution in Lake Sediments  [PDF]
Irina Schneider, Yana Topalova
Journal of Environmental Protection (JEP) , 2016, DOI: 10.4236/jep.2016.75053

A risk situation of organic pollutants accumulation in the sediments of the dams from Cascade “Middle Iskar” (NW Bulgaria) is simulated in the present study. The aim is risk modelling of organic pollution in lake sediments and on base of the investigated key chemical and enzymological parameters to risk assessment. A model process in lab scale with addition of whey as a source of organic pollutants was simulated. Two situations near to real conditions were studied: 1) at a decreased concentration of organic pollutants (chemical oxygen demand was 0.265 gO2.kg-1) in the case of discharge of sediments downstream of the river (control situation); 2) at an accumulation of organic pollutants (chemical oxygen demand was 1.463 gO2.kg-1) in the sediments (risk event). The dynamics of chemical oxygen demand (COD), concentration of proteins and lactose as well as of the key enzymological indicators (phosphatase activity index—PAI, anaerobic dehydrogenase activity, protease and ?-galactosidase activities) were investigated. The data from Risk Assessment showed that there is a hazard from higher protein concentration at the end of the process in comparison with the control situation. The risk about COD and lactose concentration during the risk modelling was acceptable. The obtained results showed that the PAI can be used as an indicator for early warning of the organic pollution with protein nature.

The Exact and Approximate Solutions of Some Boundary Value Problems in Domains with Angular Points of the Boundary  [PDF]
Irina Menshova, Mikhail Kovalenko
Journal of Applied Mathematics and Physics (JAMP) , 2017, DOI: 10.4236/jamp.2017.51006
On the basis of the exact solution of biharmonic problems of elasticity theory in a half-strip one possible reason is shown of those problems that arise when an approximate or numerical approaches leading the solution of boundary value problems to infinite systems of linear algebraic equations. Construction of exact solutions of some boundary value problems for differential equations in partial derivatives is not possible without their extensions to Riemann surfaces. Moreover, each of the boundary value problem corresponds to its Riemann surface. This fact is important to consider when developing an effective approximate and numerical methods of solving boundary value problems.
Page 1 /2308
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.