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Versatile and Simple Approach to Determine Astrocyte Territories in Mouse Neocortex and Hippocampus  [PDF]
Antje Grosche, Jens Grosche, Mark Tackenberg, Dorit Scheller, Gwendolyn Gerstner, Annett Gumprecht, Thomas Pannicke, Petra G. Hirrlinger, Ulrika Wilhelmsson, Kerstin Hüttmann, Wolfgang H?rtig, Christian Steinh?user, Milos Pekny, Andreas Reichenbach
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069143
Abstract: Background Besides their neuronal support functions, astrocytes are active partners in neuronal information processing. The typical territorial structure of astrocytes (the volume of neuropil occupied by a single astrocyte) is pivotal for many aspects of glia–neuron interactions. Methods Individual astrocyte territorial volumes are measured by Golgi impregnation, and astrocyte densities are determined by S100β immunolabeling. These data are compared with results from conventionally applied methods such as dye filling and determination of the density of astrocyte networks by biocytin loading. Finally, we implemented our new approach to investigate age-related changes in astrocyte territories in the cortex and hippocampus of 5- and 21-month-old mice. Results The data obtained by our simplified approach based on Golgi impregnation were compared to previously published dye filling experiments, and yielded remarkably comparable results regarding astrocyte territorial volumes. Moreover, we found that almost all coupled astrocytes (as indicated by biocytin loading) were immunopositive for S100β. A first application of this new experimental approach gives insight in age-dependent changes in astrocyte territorial volumes. They increased with age, while cell densities remained stable. In 5-month-old mice, the overlap factor was close to 1, revealing little or no interdigitation of astrocyte territories. However, in 21-month-old mice, the overlap factor was more than 2, suggesting that processes of adjacent astrocytes interdigitate. Conclusion Here we verified the usability of a simple, versatile method for assessing astrocyte territories and the overlap factor between adjacent territories. Second, we found that there is an age-related increase in territorial volumes of astrocytes that leads to loss of the strict organization in non-overlapping territories. Future studies should elucidate the physiological relevance of this adaptive reaction of astrocytes in the aging brain and the methods presented in this study might be a powerful tool to do so.
Simple binary segmentation frameworks for identifying variation in DNA copy number  [cached]
Yang Tae Young
BMC Bioinformatics , 2012, DOI: 10.1186/1471-2105-13-277
Abstract: Background Variation in DNA copy number, due to gains and losses of chromosome segments, is common. A first step for analyzing DNA copy number data is to identify amplified or deleted regions in individuals. To locate such regions, we propose a circular binary segmentation procedure, which is based on a sequence of nested hypothesis tests, each using the Bayesian information criterion. Results Our procedure is convenient for analyzing DNA copy number in two general situations: (1) when using data from multiple sources and (2) when using cohort analysis of multiple patients suffering from the same type of cancer. In the first case, data from multiple sources such as different platforms, labs, or preprocessing methods are used to study variation in copy number in the same individual. Combining these sources provides a higher resolution, which leads to a more detailed genome-wide survey of the individual. In this case, we provide a simple statistical framework to derive a consensus molecular signature. In the framework, the multiple sequences from various sources are integrated into a single sequence, and then the proposed segmentation procedure is applied to this sequence to detect aberrant regions. In the second case, cohort analysis of multiple patients is carried out to derive overall molecular signatures for the cohort. For this case, we provide another simple statistical framework in which data across multiple profiles is standardized before segmentation. The proposed segmentation procedure is then applied to the standardized profiles one at a time to detect aberrant regions. Any such regions that are common across two or more profiles are probably real and may play important roles in the cancer pathogenesis process. Conclusions The main advantages of the proposed procedure are flexibility and simplicity.
Mycobacteriophages as versatile tools for genetic manipulation of mycobacteria and development of simple methods for diagnosis of mycobacterial diseases
Stella,E. J.; De La Iglesia,A. I.; Morbidoni,H. R.;
Revista argentina de microbiolog?-a , 2009,
Abstract: tuberculosis, caused by mycobacterium tuberculosis, is responsible for over two million deaths per year worldwide. due to its long doubling time (18 h), the microbiological detection of m. tuberculosis by conventional methods takes up to one month, unless the number of bacilli in the biological sample is high enough. thus, drug resistance assessment requires at least one month for obtaining the primary culture and another month to determine its susceptibility to antimycobacterial drugs. moreover, for a long time, the lack of genetic tools for mycobacteria has been a barrier for undertaking studies aimed at understanding the mechanisms of drug resistance and drug target identification, being all these topics of utmost importance considering the increase in the number of drug-resistant clones and the few therapeutic options available. mycobacteriophages are promising as a novel source of genetic elements for mycobacteria manipulation, as well as for the development of versatile, simple, fast and cheap methods for drug resistance assessment of m. tuberculosis clinical isolates. we herein describe the background related to the use of mycobacteriophages, with emphasis placed on their utilization for drug resistance analysis in our country.
A Simple and Versatile 2-Dimensional Platform to Study Plant Germination and Growth under Controlled Humidity  [PDF]
Tom Sizmur, Kara R. Lind, Saida Benomar, Hannah VanEvery, Ludovico Cademartiri
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0096730
Abstract: We describe a simple, inexpensive, but remarkably versatile and controlled growth environment for the observation of plant germination and seedling root growth on a flat, horizontal surface over periods of weeks. The setup provides to each plant a controlled humidity (between 56% and 91% RH), and contact with both nutrients and atmosphere. The flat and horizontal geometry of the surface supporting the roots eliminates the gravitropic bias on their development and facilitates the imaging of the entire root system. Experiments can be setup under sterile conditions and then transferred to a non-sterile environment. The system can be assembled in 1-2 minutes, costs approximately 8.78$ per plant, is almost entirely reusable (0.43$ per experiment in disposables), and is easily scalable to a variety of plants. We demonstrate the performance of the system by germinating, growing, and imaging Wheat (Triticum aestivum), Corn (Zea mays), and Wisconsin Fast Plants (Brassica rapa). Germination rates were close to those expected for optimal conditions.
Researches on Competitors’ Behavior Response Model in Telecom Market
Jianjiang Wu
International Journal of Business and Management , 2009,
Abstract: The competition in telecom market becomes more severe. In order to response to the complicated competition, we should research the competitors’ behavior response model. By means of understanding competitors’ aims, strategies, advantages and disadvantages and collecting their information as more as possible, we can predict competitors’ possible action and whether they will response to others’ behaviors, such as decreasing price, increasing promotion or introducing new products, or not. By this way, we can judge the competitors’ response model, which can benefit us in many ways, such as setting up effective competition strategies, avoiding strong responses of competitors, defending themselves from competitors, protecting themselves with strong defense against attack, judging the possibilities and speed of competitors’ response, and so on. As a result, we can constitute effective market strategies and decrease the negative effects of competitors’ response.
Behavioral Comparisons of Cloned and Non-cloned Pigs
F.C. Gwazdauskas,A.H. Walters,M.L. McGilliard,S.F. Ball,N. Ellefson,S.S. Flesher,L.L. Keyes,W.F. Nicholson,K.S. Rosoff,K.A. Strahsmeier,M.R. Wheeler,I.A. Polejaeva,D.L. Ayares
Journal of Animal and Veterinary Advances , 2012,
Abstract: The goal of this study was to evaluate whether there were differences in behaviors of cloned and non-cloned pigs. The objectives were 1) to evaluate maintenance behaviors; 2) to determine the establishment of dominance; 3) to assess learning; and 4) to appraise farrowing and mothering abilities of cloned and non-cloned gilts. Maintenance behaviors recorded at 15-min intervals over a 12-h period were not different in terms of the frequencies of lying, standing, feeding and rooting between groups (clone vs. non-clone). There was a group by time interaction (P < 0.05) for aggressive encounters, with cloned gilts more active in late morning. With short term paired feeding tests there were no significant effects of group on attempts to eat. Learning ability was evaluated using a problem-solving maze with a feed reward. There were no differences between groups finding the reward. Total litter weight was not affected by numbers of piglets born alive, farrowing score, mothering score, dominance score, or learning score. Average piglet birth weight was affected (P < 0.05) by the number of piglets born, but not by the other independent variables. In general, the behavior of cloned gilts was not different from that of non-cloned gilts.
Mohsen Kazemi,Judith Waalen,Christopher Morgan,Anthony R. White
Journal of Sports Science and Medicine , 2006,
Abstract: The purpose of this study was to identify the profile of the Olympic champions and the other competitors who were involved in the Games. The information on each of the athletes was obtained from the "Official Site of the Sydney 2000 Olympic Games, www.olympics.com/eng/sports/TK" and included weight category, weight, height, age, points obtained, warnings, deduction point, defensive/offensive kicks and punches. One hundred and two athletes competed (54 males and 48 females) in the Games. The mean average age and BMI (Body Mass Index) of 16 male winners was 24.4 ± 3.3 years and 21.9 ± 2.4 respectively compared to 25.2 ± 4.3 years and 22.8 ± 3.3 for the 38 male non-winners. The mean average age and BMI of the 16 female winners was 23.1 ± 3.9 years and 20.8 ± 2.3 respectively compared to 24.9 ± 4.7 years and 21.3 ± 2.7 for the 32 female non-winners. For all four types of athletes, offensive kicks accounted for at least 52% of the techniques to score a point. Ninety-eight percent of all techniques used to score were kicks. Although not statistically significant, winners overall tended to be younger in age and taller with slightly lower BMI than their weight category average. Taking into account the literature cited in this article, future studies should be designed to examine the relationship between performance and functional variables such as muscle power, muscle endurance, reaction time and aerobic capacity.
Novelties in Competition Regulation in Romania. Impact on Competitors  [PDF]
Theoretical and Applied Economics , 2011,
Abstract: Upon the coming into force of the Law No. 149/2011, the recent changes in the Competition Law bring a significant decrease of the fines level, while encouraging competitors to support the maintenance of a healthy and transparent competition. However, some provisions require application guidelines, while others are tougher than the European law principles.
Deletion of imperfect cloned copies  [PDF]
Satyabrata Adhikari,Binayak. S. Choudhury
Physics , 2005,
Abstract: In this work, we design a deleting machine and shown that for some given condition on machine parameters, it gives slightly better result than P-B deleting machine [5,6]. Also it is shown that for some particular values of the machine parameters it acts like Pati-Braunstein deleting machine. We also study the combined effect of cloning and deleting machine, where at first the cloning is done by some standard cloning machines such as Wootters-Zurek [1] and Buzek-Hillery [2] cloning machine and then the copy mode is deleted by Pati-Braunstein deleting machine or our prescribed deleting machine. After that we examine the distortion of the input state and the fidelity of deletion .
First dog cloned
Ivan Oransky
Genome Biology , 2004, DOI: 10.1186/gb-spotlight-20050818-02
Abstract: The puppy–named Snuppy for the researchers' Seoul National University–was born by cesarean section on April 24 to a yellow Labrador surrogate mother and turned 100 days old yesterday (August 2). A second cloned dog lived just 22 days before succumbing to aspiration pneumonia. A postmortem analysis showed no signs of "any congenital defect due to cloning," said Woo Suk Hwang, the leader of the Korean team. A third pregnancy resulted in a miscarriage.Until now, somatic cell cloning in dogs has been hampered by limited success in maturing canine oocytes in vitro, said Hwang. Such maturation is necessary because unlike those of other domestic animals, canine oocytes aren't mature at ovulation. They're ovulated at prophase of the first meiotic division and undergo maturation in the distal part of the oviduct for at least 48 to 72 hours. The dog's opaque ova also make manipulation difficult.Hwang attributed his team's success to their ability to produce a nuclear transfer construct using in vivo matured oocytes, to transfer it into a surrogate mother at an early stage of development without in vitro embryo culture, and to optimize the conditions for transfer "through trial and error.""We were able to determine the exact ovulation and embryo transfer time," Hwang told The Scientist via E-mail. "Through hormonal and cellular analysis of vaginal smears, we made a database for prediction of ovulation time and for estrus synchronization. Thus, our team could obtain a good number of in vivo matured oocytes with good quality and find good surrogate mothers with an appropriate estrous cycle."Altogether, the researchers collected an average of 12 oocytes from 123 donor females to create nearly 1,500 successfully reconstructed embryos. Of those, 1,095 were transferred back into the same 123 surrogates. The researchers used "naturally collected eggs" rather than the hormone stimulation typical of in vitro fertilization, coauthor Gerald Schatten, of the University of Pittsburgh, note
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