2,920 research outputs found
Primate Primordial Germ Cells Acquire Transplantation Potential by Carnegie Stage 23.
Primordial germ cells (PGCs) are the earliest embryonic progenitors in the germline. Correct formation of PGCs is critical to reproductive health as an adult. Recent work has shown that primate PGCs can be differentiated from pluripotent stem cells; however, a bioassay that supports their identity as transplantable germ cells has not been reported. Here, we adopted a xenotransplantation assay by transplanting single-cell suspensions of human and nonhuman primate embryonic Macaca mulatta (rhesus macaque) testes containing PGCs into the seminiferous tubules of adult busulfan-treated nude mice. We discovered that both human and nonhuman primate embryonic testis are xenotransplantable, generating colonies while not generating tumors. Taken together, this work provides two critical references (molecular and functional) for defining transplantable primate PGCs. These results provide a blueprint for differentiating pluripotent stem cells to transplantable PGC-like cells in a species that is amenable to transplantation and fertility studies
Comprehensive Analysis of Market Conditions in the Foreign Exchange Market: Fluctuation Scaling and Variance-Covariance Matrix
We investigate quotation and transaction activities in the foreign exchange
market for every week during the period of June 2007 to December 2010. A
scaling relationship between the mean values of number of quotations (or number
of transactions) for various currency pairs and the corresponding standard
deviations holds for a majority of the weeks. However, the scaling breaks in
some time intervals, which is related to the emergence of market shocks. There
is a monotonous relationship between values of scaling indices and global
averages of currency pair cross-correlations when both quantities are observed
for various window lengths .Comment: 13 pages, 10 figure
SOX9 Maintains Reserve Stem Cells and Preserves Radioresistance in Mouse Small Intestine
Reserve intestinal stem cells (rISCs) are quiescent/slowly cycling under homeostatic conditions, allowing for their identification with label-retention assays. rISCs mediate epithelial regeneration after tissue damage by converting to actively proliferating stem cells (aISCs) that self renew and demonstrate multipotency, which are defining properties of stem cells. Little is known about the genetic mechanisms that regulate the production and maintenance of rISCs. High expression levels of the transcription factor Sox9 (Sox9high) are associated with rISCs. This study investigates the role of SOX9 in regulating the rISC state
Protein Carbonylation of an Amino Acid Residue of the Na/KāATPase Ī±1 Subunit Determines Na/KāATPase Signaling and Sodium Transport in Renal Proximal Tubular Cells
Background We have demonstrated that cardiotonic steroids, such as ouabain, signaling through the Na/KāATPase, regulate sodium reabsorption in the renal proximal tubule. By direct carbonylation modification of the Pro222 residue in the actuator (A) domain of pig Na/KāATPase Ī±1 subunit, reactive oxygen species are required for ouabaināstimulated Na/KāATPase/cāSrc signaling and subsequent regulation of active transepithelial 22Na+ transport. In the present study we sought to determine the functional role of Pro222 carbonylation in Na/KāATPase signaling and sodium handling.
Methods and Results Stable pig Ī±1 knockdown LLCāPK1āoriginated PYā17 cells were rescued by expressing wildātype rat Ī±1 and rat Ī±1 with a single mutation of Pro224 (corresponding to pig Pro222) to Ala. This mutation does not affect ouabaināinduced inhibition of Na/KāATPase activity, but abolishes the effects of ouabain on Na/KāATPase/cāSrc signaling, protein carbonylation, Na/KāATPase endocytosis, and active transepithelial 22Na+ transport.
Conclusions Direct carbonylation modification of Pro224 in the rat Ī±1 subunit determines ouabaināmediated Na/KāATPase signal transduction and subsequent regulation of renal proximal tubule sodium transport
Experiences Building Globus Genomics: A Next-Generation Sequencing Analysis Service using Galaxy, Globus, and Amazon Web Services
ABSTRACT We describe Globus Genomics, a system that we have developed for rapid analysis of large quantities of next-generation sequencing (NGS) genomic data. This system achieves a high degree of end-to-end automation that encompasses every stage of data analysis including initial data retrieval from remote sequencing centers or storage (via the Globus file transfer system); specification, configuration, and reuse of multi-step processing pipelines (via the Galaxy workflow system); creation of custom Amazon Machine Images and on-demand resource acquisition via a specialized elastic provisioner (on Amazon EC2); and efficient scheduling of these pipelines over many processors (via the HTCondor scheduler). The system allows biomedical researchers to perform rapid analysis of large NGS datasets in a fully automated manner, without software installation or a need for any local computing infrastructure. We report performance and cost results for some representative workloads
Attenuation of Na/K-ATPase Mediated Oxidant Amplification with pNaKtide Ameliorates Experimental Uremic Cardiomyopathy
We have previously reported that the sodium potassium adenosine triphosphatase (Na/K-ATPase) can effect the amplification of reactive oxygen species. In this study, we examined whether attenuation of oxidant stress by antagonism of Na/K-ATPase oxidant amplification might ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy (PNx). PNx induced the development of cardiac morphological and biochemical changes consistent with human uremic cardiomyopathy. Both inhibition of Na/K-ATPase oxidant amplification with pNaKtide and induction of heme oxygenase-1 (HO-1) with cobalt protoporphyrin (CoPP) markedly attenuated the development of phenotypical features of uremic cardiomyopathy. In a reversal study, administration of pNaKtide after the induction of uremic cardiomyopathy reversed many of the phenotypical features. Attenuation of Na/K-ATPase oxidant amplification may be a potential strategy for clinical therapy of this disorder
A Student\u27s Guide to giant Viruses Infecting Small Eukaryotes: From Acanthamoeba to Zooxanthellae
The discovery of infectious particles that challenge conventional thoughts concerning āwhat is a virusā has led to the evolution a new field of study in the past decade. Here, we review knowledge and information concerning āgiant virusesā, with a focus not only on some of the best studied systems, but also provide an effort to illuminate systems yet to be better resolved. We conclude by demonstrating that there is an abundance of new hostāvirus systems that fall into this āgiantā category, demonstrating that this field of inquiry presents great opportunities for future research
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