bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dmdmdx/Largemyd: a new mouse model of neuromuscular diseases useful for studying physiopathological mechanisms and testing therapies
Authors: Martins Poliana C. M. , Ayub-Guerrieri Danielle , Martins-Bach Aurea B. , Onofre-Oliveira Paula , Malheiros Jackeline M. , Tannus Alberto , de Sousa Paulo L. , Carlier Pierre G. , Vainzof Mariz 
Published: June 2013

Summary
Although muscular dystrophies are among the most common human genetic disorders, there are few treatment options available. Animal models have become increasingly important for testing new therapies prior to entering human clinical trials. The DMDmdx mouse is the most widely used animal model for Duchenne muscular dystrophy (DMD), presenting the same molecular and protein defect as seen in humans with the disease. However, this mouse is not useful for clinical trials, because of its very mild phenotype. The mouse model for congenital myodystrophy type 1D, Largemyd, harbors a mutation in the glycosyltransferase Large gene and displays a severe phenotype. To help elucidate the role of the proteins dystrophin and LARGE in the organization of the dystrophin-glycoprotein complex in muscle sarcolemma, we generated double-mutant mice for the dystrophin and LARGE proteins. The new DMDmdx/Largemyd mouse model is viable and shows a severe phenotype that is associated with the lack of dystrophin in muscle. We tested the usefulness of our new mouse model for cell therapy by systemically injecting them with normal murine mesenchymal adipose stem cells (mASCs). We verified that the mASCs were hosted in the dystrophic muscle. The new mouse model has proven to be very useful for the study of several other therapies, because injected cells can be screened both through DNA and protein analysis. Study of its substantial muscle weakness will also be very informative in the evaluation of functional benefits of these therapies.
Mutant Enpp1asj mice as a model for generalized arterial calcification of infancy
Authors: Li Qiaoli , Guo Haitao , Chou David W. , Berndt Annerose , Sundberg John P. , Uitto Jouni 
Published: June 2013

Summary
Generalized arterial calcification of infancy (GACI), an autosomal recessive disorder, is characterized by early mineralization of blood vessels, often diagnosed by prenatal ultrasound and usually resulting in demise during the first year of life. It is caused in most cases by mutations in the ENPP1 gene, encoding an enzyme that hydrolyzes ATP to AMP and inorganic pyrophosphate, the latter being a powerful anti-mineralization factor. Recently, a novel mouse phenotype was recognized as a result of ENU mutagenesis - those mice developed stiffening of the joints, hence the mutant mouse was named 'ages with stiffened joints' (asj). These mice harbor a missense mutation, p.V246D, in the Enpp1 gene. Here we demonstrate that the mutant ENPP1 protein is largely absent in the liver of asj mice, and the lack of enzymatic activity results in reduced inorganic pyrophosphate (PPi) levels in the plasma, accompanied by extensive mineralization of a number of tissues, including arterial blood vessels. The progress of mineralization is highly dependent on the mineral composition of the diet, with significant shortening of the lifespan on a diet enriched in phosphorus and low in magnesium. These results suggest that the asj mouse can serve as an animal model for GACI.
Muscle growth in teleost fish is regulated by factors utilizing the activin II B receptor
Authors: Phelps Michael P. , Jaffe Ian M. , Bradley Terence M. 
Published: June 2013

SummaryThe activin type IIB receptor (Acvr2b) is the cell surface receptor for multiple transforming growth factor β (TGF-β) superfamily ligands, several of which regulate muscle growth in mammals. To investigate the role of the Acvr2b signaling pathway in the growth and development of skeletal muscle in teleost fish, transgenic rainbow trout (RBT; Oncorhynchus mykiss, Walbaum) expressing a truncated form of the acvr2b-2a (acvr2bΔ) in muscle tissue were produced. High levels of acvr2bΔ expression were detected in the majority of P1 transgenic fish. Transgenic P1 trout developed enhanced, localized musculature in both the epaxial and hypaxial regions (dubbed "six pack"). The F1 transgenic offspring did not exhibit localized muscle growth, but rather developed a uniform body morphology with greater girth, condition factor, and increased muscle fiber hypertrophy. There was a high degree of variation in the weight of both P1 and F1 transgenic fish with several fish of each generation exhibiting enhanced growth compared to other transgenic and control siblings. The "six pack" phenotype observed in P1 transgenic RBT overexpressing a acvr2bΔ and the presence of F1 individuals with altered muscle morphology provides compelling evidence for the importance of TGF-β signaling molecules in regulating muscle growth in teleost fish.
Social descent with territory loss causes rapid behavioral, endocrine, and transcriptional changes in the brain
Authors: Maruska Karen P. , Becker Lisa , Neboori Anoop , Fernald Russell D. 
Published: June 2013

Summary
In social species that form hierarchies where only dominant males reproduce, lower-ranking individuals may challenge higher-ranking ones, often resulting in changes in relative social status. How does a losing animal respond to loss of status? Here, using an African cichlid fish Astatotilapia burtoni, we manipulated the social environment causing males to descend in rank and then examined changes in behavior, circulating steroids, and immediate early gene (IEG) expression (cfos, egr-1) in micro-dissected brain regions as a proxy for neuronal activation. In particular, we examined changes in the conserved 'social behavior network' (SBN), a collection of brain nuclei known to regulate social behaviors across vertebrates. A. burtoni has rapidly reversible dominant-subordinate male phenotypes, so that within minutes, descending males lost their bright body-coloration, switched to submissive behaviors, and expressed higher plasma cortisol levels compared to non-descending and control males. Descending males had higher IEG expression throughout the SBN, but each brain region showed a distinct IEG-specific response in either cfos or egr-1 levels, but not both. Overall SBN IEG patterns in descending males were distinctly different from the pattern observed in males ascending (subordinate to dominant) in social status. These results reveal that the SBN rapidly coordinates the perception of social cues about status that are of opposite valence, and translates them into appropriate phenotypic changes. This shows for the first time in a non-mammalian vertebrate that dropping in social rank rapidly activates specific socially-relevant brain nuclei in a pattern that differs from when males rise to a higher status position.
The gene vitellogenin affects microRNA regulation in honey bee (Apis mellifera) fat body and brain
Authors: Nunes Francis M. F. , Ihle Kate E. , Mutti Navdeep S. , Simões Zilá L. P. , Amdam Gro V. 
Published: June 2013

SummaryIn honey bees, Vitellogenin (Vg) is hypothesized to be a major factor affecting hormone signaling, food-related behavior, immunity, stress resistance and lifespan. Likewise microRNAs play important roles in posttranscriptional gene regulation and affect many biological processes. The action of microRNAs and Vg are known to intersect in the context of reproduction; however, the role of these associations on social behavior is unknown. The phenotypic effects of Vg knockdown are best established and studied in the forager stage of workers. Thus, we exploited the well-established RNA interference (RNAi) protocol for Vg knockdown to investigate its downstream effects on microRNA population in honey bee foragers' brain and fat body tissue. To identify microRNAs that are differentially expressed between tissues in control and knockdown foragers, we used µParaflo® microfluidic oligonucleotide microRNA microarrays. Our results show 76 and 74 microRNAs were expressed in the brain of control and knockdown foragers whereas 66 and 69 microRNAs were expressed in the fat body of control and knockdown foragers respectively. Target prediction identified potential seed matches for a differentially expressed subset of microRNAs affected by Vg knockdown. These candidate genes are involved in a broad range of biological processes including insulin signaling, juvenile hormone (JH) and ecdysteroid signaling previously shown to affect foraging behavior. Thus, here we demonstrate a causal link between the Vg knockdown forager phenotype and variation in the abundance of microRNAs in different tissues with possible consequences for regulation of foraging behavior.
Homing abilities of the Australian intertidal ant, Polyrhachis sokolova
Authors: Narendra Ajay , Raderschall Chloe , Robson Simon 
Published: June 2013

Summary
The pressure of returning and locating the nest after a successful foraging trip is immense in ants. To find their way back home, ants use a number of different strategies (e.g., path integration, trail-following) and rely on a range of cues (e.g., pattern of polarised skylight, landmark panorama) available in their environment. How ants weigh different cues has been a question of great interest and has primarily been addressed in the desert ants from Africa and Australia. We here identify the navigational abilities of an intertidal ant, Polyrhachis sokolova that lives on mudflats where nests and foraging areas are frequently inundated with tidal water. We find that these solitary foraging ants rely heavily on visual landmark information for navigation but they are also capable of path integration. By displacing ants with and without vector information at different locations within the local familiar territory we created conflicts between information from the landmarks and the path integrator. The homing success of full-vector ants, compared to the zero-vector ants, when displaced 5 m behind the feeder indicate that vector information had to be coupled with landmark information for successful homing. To explain the differences in the homing abilities of ants from different locations we determined the navigational information content at each release station and compared it to that available at the feeder location. We report here the interaction of multiple navigation strategies in the context of the information content in the environment.
Physiological and behavioural effects of fruit toxins on seed-predating versus seed-dispersing congeneric rodents
Authors: Samuni-Blank Michal , Izhaki Ido , Dearing Denise , Karasov William , Gerchman Yoram , Kohl Kevin , Lymberakis Petros , Kurnath Patrice , Arad Zeev 
Published: June 2013

SummaryFleshy, ripe fruits attract seed dispersers but also seed predators. Although many fruit consumers (legitimate seed dispersers as well as seed predators) are clearly exposed to plant secondary compounds (PSCs), their impact on the consumers’ physiology and foraging behaviour has been largely overlooked. Here, we document the divergent behavioural and physiological responses of three congeneric rodent species in the Middle East, seed dispersers versus seed predators, to fruit consumption. The fruit pulp of the desert plant Ochradenus baccatus contains high concentrations of glucosinolates (GLSs). These GLSs are hydrolyzed into active toxic compounds upon contact with the myrosinase enzyme released from seeds crushed during fruit consumption. Acomys russatus and A. cahirinus share a desert habitat. Acomys russatus acts as an O. baccatus seed predator, and A. cahirinus circumvents the activation of the GLSs by orally expelling vital seeds. We found that between the three species examined, A. russatus was physiologically most tolerant to whole fruit consumption and even A. minous, which is evolutionarily naïve to O. baccatus, exhibits greater tolerance to whole fruit consumption than A. cahirinus. However, like A. cahirinus, A. minous may also behaviourally avoid the activation of the GLSs by making a hole in the pulp and consuming only the seeds. Our findings demonstrate that seed predators have a higher physiological tolerance than seed dispersers when consuming fruits containing toxic PSCs. The findings also demonstrate the extreme ecological/evolutionary ability of this plant-animal symbiosis to shift from predation to mutualism and vice versa.
Electroporation of adherent cells with low sample volumes on a microscope stage
Authors: Tsugiyama Harunobu , Okimura Chika , Mizuno Takafumi , Iwadate Yoshiaki 
Published: June 2013

Summary
The labeling of specific molecules and their artificial control in living cells are powerful techniques for investigating intracellular molecular dynamics. To use these techniques, molecular compounds (hereinafter described simply as "samples") need to be loaded into cells. Electroporation techniques are exploited to load membrane-impermeant samples into cells. Here, we developed a new electroporator with four special characteristics: (1) Electric pulses are applied to the adherent cells directly, without removing them from the substratum. (2) Samples can be loaded into the adherent cells while observing them on the stage of an inverted microscope. (3) Only 2 μl of sample solution is sufficient. (4) The device is very easy to use, since the cuvette, which is connected to the tip of a commercially available auto-pipette, is manipulated by hand. Using our device, we loaded a fluorescent probe of actin filaments, Alexa Fluor 546 phalloidin, into migrating keratocytes. The level of this probe in the cells could be easily adjusted by changing its concentration in the electroporation medium. Samples could be loaded into keratocytes, neutrophil-like HL-60 cells and Dictyostelium cells on a coverslip, and keratocytes on an elastic silicone substratum. The new device should be useful for a wide range of adherent cells and allow electroporation for cells on various types of the substrata.
Hard Magnetic Ferrite: ε-Fe2O3
Authors: Ohkoshi Shin-ichi , Tokoro Hiroko 
Published: June 2013

Abstract
Iron oxide Fe2O3 has four polymorphs: α-, β-, γ-, and ε-phases. α-Fe2O3 (hematite) and γ-Fe2O3 (maghemite) are abundant in nature, whereas β- and ε-Fe2O3 phases are very rare and must be artificially synthesized in the laboratory. Pure ε-Fe2O3 phase was first synthesized in 2004 using a combination of reverse-micelle and sol–gel techniques, and it shows the largest coercive field value (Hc) among metal oxide-based magnets of 20 kOe at room temperature. Successively, several kinds of metal-substituted ε-iron oxides, ε-MxFe2−xO3 (M = In, Ga, and Al), have been synthesized, and their magnetic properties are controlled by the degree of the metal substitution. Such iron oxides with a high Hc are attractive from industrial application viewpoints, e.g., magnetic recordings and electromagnetic wave absorbers. A series of ε-MxFe2−xO3 shows high-frequency electromagnetic wave absorption due to zero-field ferromagnetic resonance at 35–182 GHz in the millimeter range, which is useful for next-generation high-speed wireless communications. In this article, we describe (i) the synthesis, crystal structure, and magnetic properties of ε-Fe2O3, (ii) generation mechanism of ε-Fe2O3, the origin of the gigantic coercive field, and theoretical analysis of magnetic ordering, (iii) metal-substituted ε-iron oxides, ε-MxFe2−xO3, and (iv) electromagnetic wave absorption in the millimeter wave range.
Catalytic Alkane Oxidation by Homogeneous and Silica-supported Cobalt(II) Complex Catalysts with a Triazolyl Group-containing Tetradentate Ligand
Authors: Nakazawa Jun , Yata Akinori , Hori Tomoaki , Stack T Daniel P , Naruta Yoshinori , Hikichi Shiro 
Published: June 2013

Abstract
Homogeneous and heterogeneous cobalt complex catalysts with bis(pyridylmethyl)(triazolylmethyl)amine ligand were prepared. Although simple cobalt salts catalyze cyclohexane oxidation with mCPBA, the cyclohexane selectivity increases upon coordination of tetradentate ligands. In the heterogeneous catalysis, the yield and selectivity of cyclohexanol are improved with an increase in the ligand density on the silica support due to the suppression of metal leaching.
Labor Market and Search through Personal Contacts
Authors: Chuhay Roman 
Published: June 2013

AbstractIn this article, we consider the impact of personal contacts on the labor market outcome. Unlike previous studies, we do not assume any particular network structure or vacancies communication protocol. Instead, we state three general properties of matching functions that allow us to establish the existence and uniqueness of equilibrium and characterize the impact of social ties on the labor market. In particular, we show that a monotonically increasing matching function in socialization level is a necessary and sufficient condition for having monotonically decreasing unemployment and increasing wage and market tightness. However, the same does not apply to vacancy rate. We establish a condition under which a monotonically increasing matching function produces a vacancy rate that first increases in socialization level, but then decreases.
Dictatorial Mechanisms in Constrained Combinatorial Auctions
Authors: Lerner Anat , Gonen Rica 
Published: June 2013

AbstractWe study the possibility space of deterministic, dominant-strategy incentive compatible, individually rational, and Pareto efficient combinatorial auctions in a model with two players and two nonidentical items (four outcomes). Our model has multidimensional types, private values, nonnegative prices, and quasilinear preferences for the players with one relaxation – the players are subject to publicly known budget constraints. We show that the space we study essentially includes one type of mechanisms: autocratic mechanisms (a form of dictatorship). Furthermore, we prove that there are families of autocratic mechanisms that uniquely fulfill the basic properties of deterministic, dominant-strategy incentive compatible, individually rational, and Pareto efficient. The mechanisms in the autocratic families are identical except for two to three price parameters that differentiate them.
Neural Network-Based Sensor Fault Accommodation in Flight Control System
Authors: Singh Seema , Murthy T. V. Rama 
Published: June 2013

AbstractThis article deals with detection and accommodation of sensor faults in longitudinal dynamics of an F8 aircraft model. Both the detection of the fault and reconfiguration of the failed sensor are done with the help of neural network-based models. Detection of a sensor fault is done with the help of knowledge-based neural network fault detection (KBNNFD). Apart from KBNNFD, another neural network model is developed in this article for the reconfiguration of the failed sensor. A model-based approach of the neural network (MBNN) is developed, which uses the radial basis function of the neural network. MBNN successfully does the task of providing analytical redundancy for the aircraft sensor. In this work, both detection and reconfiguration of a fault is done using neural networks. Hence, the control system becomes robust for handling sensor failures near steady state and reconfiguration is also faster. A generalized regression neural network (GRNN), which is a type of radial basis network, is used for MBNN, which gives very efficient results for function approximation. An F8 aircraft model and C-Star controller, which improves its handling quality, are used for validation of the method involved. Models of F8 aircraft, C-Star controller, KBNNFD, and MBNN were developed using MATLAB/Simulink. Successful implementation and simulation results are shown and discussed using Simulink.
Differences and similarities in the transcriptional profile of peripheral whole blood in early and late-onset preeclampsia: insights into the molecular basis of the phenotype of preeclampsiaa
Authors: Chaiworapongsa Tinnakorn , Romero Roberto , Whitten Amy , Tarca Adi L. , Bhatti Gaurav , Draghici Sorin , Chaemsaithong Piya , Miranda Jezid , Hassan Sonia S. 
Published: June 2013

Abstract

Objective: Preeclampsia (PE) can be sub-divided into early- and late-onset phenotypes. The pathogenesis of these two phenotypes has not been elucidated. To gain insight into the mechanisms of disease, the transcriptional profiles of whole blood from women with early- and late-onset PE were examined.

Methods: A cross-sectional study was conducted to include women with: i) early-onset PE (diagnosed prior to 34 weeks, n=25); ii) late-onset PE (after 34 weeks, n=47); and iii) uncomplicated pregnancy (n=61). Microarray analysis of mRNA expression in peripheral whole blood was undertaken using Affymetrix microarrays. Differential gene expression was evaluated using a moderated t-test (false discovery rate <0.1 and fold change >1.5), adjusting for maternal white blood cell count and gestational age. Validation by real-time qRT-PCR was performed in a larger sample size [early PE (n=31), late PE (n=72) and controls (n=99)] in all differentially expressed genes. Gene ontology analysis and pathway analysis were performed.

Results: i) 43 and 28 genes were differentially expressed in early- and late-onset PE compared to the control group, respectively; ii) qRT-PCR confirmed the microarray results for early and late-onset PE in 77% (33/43) and 71% (20/28) of genes, respectively; iii) 20 genes that are involved in coagulation (SERPINI2), immune regulation (VSIG4, CD24), developmental process (H19) and inflammation (S100A10) were differentially expressed in early-onset PE alone. In contrast, only seven genes that encoded proteins involved in innate immunity (LTF, ELANE) and cell-to-cell recognition in the nervous system (CNTNAP3) were differentially expressed in late-onset PE alone. Thirteen genes that encode proteins involved in host defense (DEFA4, BPI, CTSG, LCN2), tight junctions in blood-brain barrier (EMP1) and liver regeneration (ECT2) were differentially expressed in both early- and late-onset PE.

Conclusion: Early- and late-onset PE are characterized by a common signature in the transcriptional profile of whole blood. A small set of genes were differentially regulated in early- and late-onset PE. Future studies of the biological function, expression timetable and protein expression of these genes may provide insight into the pathophysiology of PE.
New thermally stable poly(amide-imide)/montmorillonite reinforced nanocomposite based on N,N′-pyrromellitoyl-bis-l-valine: synthesis and characterization
Authors: Faghihi Khalil , Dehnavi Narges , Hajibeygi Mohsen 
Published: June 2013

Abstract
Two new samples of poly(amide-imide) (PAI)/nanocomposites reinforced montmorillonite containing N,N′-pyrromelitoyl-bis-l-valine moiety in the main chain were synthesized by a solution intercalation technique. PAI 3 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N,N′-pyrromelitoyl-bis-l-valine 1 with 4,4′-diamino diphenyl ether 2 in the presence of triphenyl phosphite, CaCl2, pyridine and N-methyl-2-pyrrolidone. The morphology and structure of the resulting PAI-nanocomposite films 4a and 4b with 5% and 10% silicate particles were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-visible spectroscopy, thermogravimetric analysis and differential scanning calorimetry.