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Human pluripotent stem cells hold potential for regenerative medicine, but available cell types have significant limitations. Although embryonic stem cells (ES cells) from in vitro fertilized embryos (IVF ES cells) represent the 'gold standard', they are allogeneic to patients. Autologous induced pluripotent stem cells (iPS cells) are prone to epigenetic and transcriptional aberrations. To determine whether such abnormalities are intrinsic to somatic cell reprogramming or secondary to the reprogramming method, genetically matched sets of human IVF ES cells, iPS cells and nuclear transfer ES cells (NT ES cells) derived by somatic cell nuclear transfer (SCNT) were subjected to genome-wide analyses. Both NT ES cells and iPS cells derived from the same somatic cells contained comparable numbers of de novo copy number variations. In contrast, DNA methylation and transcriptome profiles of NT ES cells corresponded closely to those of IVF ES cells, whereas iPS cells differed and retained residual DNA methylation patterns typical of parental somatic cells. Thus, human somatic cells can be faithfully reprogrammed to pluripotency by SCNT and are therefore ideal for cell replacement therapies.

The ability to culture pluripotent stem cells and direct their differentiation into specific cell types in vitro provides a valuable experimental system for modeling pluripotency, development and cellular differentiation. High-throughput profiling of the transcriptomes and epigenomes of pluripotent stem cells and their differentiated derivatives has led to identification of patterns characteristic of each cell type, discovery of new regulatory features in the epigenome and early insights into the complexity of dynamic interactions among regulatory elements. This work has also revealed potential limitations of the use of pluripotent stem cells as in vitro models of developmental events, due to epigenetic variability among different pluripotent stem cell lines and epigenetic instability during derivation and culture, particularly at imprinted and X-inactivated loci. This review focuses on the two most well-studied epigenetic mechanisms, DNA methylation and histone modifications, within the context of pluripotency and differentiation.

Lineage conversion of one somatic cell type to another is an attractive approach for generating specific human cell types. Lineage conversion can be direct, in the absence of proliferation and multipotent progenitor generation, or indirect, by the generation of expandable multipotent progenitor states. We report the development of a reprogramming methodology in which cells transition through a plastic intermediate state, induced by brief exposure to reprogramming factors, followed by differentiation. We use this approach to convert human fibroblasts to mesodermal progenitor cells, including by non-integrative approaches. These progenitor cells demonstrated bipotent differentiation potential and could generate endothelial and smooth muscle lineages. Differentiated endothelial cells exhibited neo-angiogenesis and anastomosis in vivo. This methodology for indirect lineage conversion to angioblast-like cells adds to the armamentarium of reprogramming approaches aimed at the study and treatment of ischemic pathologies.

Aims: This study evaluates potentials of Cupriavidus necator PHB4 transformant harboring the highly activepolyhydroxyalkanoate synthase gene (phaC) of a locally isolated Chromobacterium sp. USM2 for its ability toincorporate 3-hydroxyheptanoate (3HHp) monomer.Methodology and results: A mixture of fructose and sodium heptanoate fed to the culture gave rise to poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyheptanoate), [P(3HB-co-3HV-co-3HHp)] terpolymer synthesis, withtraces of 3HHp monomers confirmed through gas chromatography (GC), proton (1H) and carbon (13C) NMR spectra.Conclusion, significance and impact of study: This study has revealed that the PHA synthase of Chromobacteriumsp. USM2 has a broad range of substrate specificity. The synthase is able to polymerize 3-hydroxyalkanoate monomershaving 4–7 carbon atoms.

In contrast to the developing testis, molecular pathways driving fetal ovarian development have been difficult to characterise. To date no single master regulator of ovarian development has been identified that would be considered the female equivalent of Sry. Using a genomic approach we identified a number of novel protein-coding as well as non-coding genes that were detectable at higher levels in the ovary compared to testis during early mouse gonad development. We were able to cluster these ovarian genes into different temporal expression categories. Of note, Lrrc34 and AK015184 were detected in XX but not XY germ cells before the onset of sex-specific germ cell differentiation marked by entry into meiosis in an ovary and mitotic arrest in a testis. We also defined distinct spatial expression domains of somatic cell genes in the developing ovary. Our data expands the set of markers of early mouse ovary differentiation and identifies a classification of early ovarian genes, thus providing additional avenues with which to dissect this process.

The development of the mammalian kidney is well conserved from mouse to man. Despite considerable temporal and spatial data on gene expression in mammalian kidney development, primarily in rodent species, there is a paucity of genes whose expression is absolutely specific to a given anatomical compartment and/or developmental stage, defined here as 'anchor' genes. We previously generated an atlas of gene expression in the developing mouse kidney using microarray analysis of anatomical compartments collected via laser capture microdissection. Here, this data is further analysed to identify anchor genes via stringent bioinformatic filtering followed by high resolution section in situ hybridisation performed on 200 transcripts selected as specific to one of 11 anatomical compartments within the midgestation mouse kidney. A total of 37 anchor genes were identified across 6 compartments with the early proximal tubule being the compartment richest in anchor genes. Analysis of minimal and evolutionarily conserved promoter regions of this set of 25 anchor genes identified enrichment of transcription factor binding sites for Hnf4a and Hnf1b, RbpJ (Notch signalling), PPARγ:RxRA and COUP-TF family transcription factors. This was reinforced by GO analyses which also identified these anchor genes as targets in processes including epithelial proliferation and proximal tubular function. As well as defining anchor genes, this large scale validation of gene expression identified a further 92 compartment-enriched genes able to subcompartmentalise key processes during murine renal organogenesis spatially or ontologically. This included a cohort of 13 ureteric epithelial genes revealing previously unappreciated compartmentalisation of the collecting duct system and a series of early tubule genes suggesting that segmentation into proximal tubule, loop of Henle and distal tubule does not occur until the onset of glomerular vascularisation. Overall, this study serves to illuminate previously ill-defined stages of patterning and will enable further refinement of the lineage relationships within mammalian kidney development.

Abstract Background The developing mouse kidney is currently the best-characterized model of organogenesis at a transcriptional level. Detailed spatial maps have been generated for gene expression profiling combined with systematic in situ screening. These studies, however, fall short of capturing the transcriptional complexity arising from each locus due to the limited scope of microarray-based technology, which is largely based on "gene-centric" models. Results To address this, the polyadenylated RNA and microRNA transcriptomes of the 15.5 dpc mouse kidney were profiled using strand-specific RNA-sequencing (RNA-Seq) to a depth sufficient to complement spatial maps from pre-existing microarray datasets. The transcriptional complexity of RNAs arising from mouse RefSeq loci was catalogued; including 3568 alternatively spliced transcripts and 532 uncharacterized alternate 3' UTRs. Antisense expressions for 60% of RefSeq genes was also detected including uncharacterized non-coding transcripts overlapping kidney progenitor markers, Six2 and Sall1, and were validated by section in situ hybridization. Analysis of genes known to be involved in kidney development, particularly during mesenchymal-to-epithelial transition, showed an enrichment of non-coding antisense transcripts extended along protein-coding RNAs. Conclusion The resulting resource further refines the transcriptomic cartography of kidney organogenesis by integrating deep RNA sequencing data with locus-based information from previously published expression atlases. The added resolution of RNA-Seq has provided the basis for a transition from classical gene-centric models of kidney development towards more accurate and detailed "transcript-centric" representations, which highlights the extent of transcriptional complexity of genes that direct complex development events.

Introduction: Good trunk performance is important for activities such as sitting and standing. In a cohort of patients with stroke, we sought to evaluate changes in trunk performance after stroke, establish factors correlated to trunk performance and assess the impact of trunk performance on discharge ambulatory and functional status.Methods: This was a retrospective review of the data of patients with stroke admitted to Tan Tock Seng Hospital rehabilitation centre, Singapore, over a two-year period. Data analysed included the National Institutes of Health Stroke Scale (NIHSS), Montreal Cognitive Assessment (MOCA), Fugl-Meyer Assessment (FMA) of limb motor impairment and Functional Independence Measure-motor (FIM-motor) scores, which measures self-care ability. Trunk performance was assessed on the Trunk Impairment Scale (TIS).Results: 577 patients with stroke (mean age 63.2 ± 11.8 years) were analysed. Truncal impairment was present in 96.4% of patients. Mean admission TIS score was 14.3 ± 6.1 and this improved to 17.2 ± 5.2 on discharge (p < 0.001). Admission TIS score was positively correlated with admission MOCA, FMA-upper limb and FMA-lower limb scores, and negatively correlated to NIHSS score and neglect. Admission TIS scores significantly predicted discharge FIM-motor scores (p < 0.001) and ambulatory status (p < 0.001).Conclusion: Truncal impairment was common and improvements in trunk performance were seen after rehabilitation. Trunk performance was significantly correlated to stroke severity, upper and lower limb motor power, cognition and neglect. As admission trunk performance predicted discharge functional and ambulatory status, it is recommended that trunk performance be evaluated for all patients with stroke. [ABSTRACT FROM AUTHOR]

The aim of the study was to carried out for identification of bioactive compounds from the whole plant methanol extract of Tinospora cordifolia by GCMS analysed by IIFPT (Iso/IEC 17025:2005). Referred standard protocol using NIST Library. The GCMS analysis revealed the presence of various compounds used for various disease. [ABSTRACT FROM AUTHOR]

Sputter deposited FeRhN films with a [B.sub.s] value of more than 20 kG were used as high moment flux enhancement layer in the write element in order to achieve a recording density of 63.2 Gb/[in.sup.2]. This layer was disposed between write gap and upper portion of the top pole, which was made of [Ni.sub.45][Fe.sub.55] with a [B.sub.s] of 16 kG. A 36 dB overwrite and nonlinear transition shift of less then -20 dB were obtained at this recording density. A finite element model was used to calculate the longitudinal field and field gradient at the medium location. The results suggested significant increases of both by incorporating the flux enhancement layer. Index Terms--High moment materials, recording demonstration, sputter deposition, write heads.