The influence of a new antitumor agent on hemopoietic colony forming cells

The cytostatic and immunsuppressive agent N'-methyl-N'-beta-chloroethylbenzaldehyde hydrazone (B1) in in-vitro experiments has a stimulating effect on colony-forming culture (CFUc) of bone marrow from C57BL mice. This unusual behaviour, which is in contrast to other cytostatics, could also be observed in vitro with CFUc obtained from mice treated with therapeutic doses of B1 for 2 weeks. This stimulation is not a particular effect of B1 alone but seems to depend on a synergistic effect of the combination of B1 and the colony-stimulating activity (CSA) present in the serum from endotoxin-treated mice (MP) in the testing system. The results suggest that the described effect of B1 is due to an interference at the cell membrane of CFUc or their precursor cells.     

Early consolidation in human primary motor cortex.

Behavioural studies indicate that a newly acquired motor skill is rapidly consolidated from an initially unstable state to a more stable state, whereas neuroimaging studies demonstrate that the brain engages new regions for performance of the task as a result of this consolidation. However, it is not known where a new skill is retained and processed before it is firmly consolidated. Some early aspects of motor skill acquisition involve the primary motor cortex (M1), but the nature of that involvement is unclear. We tested the possibility that the human M1 is essential to early motor consolidation. We monitored changes in elementary motor behaviour while subjects practised fast finger movements that rapidly improved in movement acceleration and muscle force generation. Here we show that low-frequency, repetitive transcranial magnetic stimulation of M1 but not other brain areas specifically disrupted the retention of the behavioural improvement, but did not affect basal motor behaviour, task performance, motor learning by subsequent practice, or recall of the newly acquired motor skill. These findings indicate that the human M1 is specifically engaged during the early stage of motor consolidation.     

System Dynamics and Learning Scenarios for Process Improvement and Regional Resilience: A Study in The Footwear Industry of Southern Brazil

Systemic Practice and Action Research - By means of integrated and systemic resilience strategies, it is possible to reduce vulnerability and risk, and at the same time increase the capacity to...     

Protein arginine methylation: a prominent modification and its demethylation

Arginine methylation of histones is one mechanism of epigenetic regulation in eukaryotic cells. Methylarginines can also be found in non-histone proteins involved in various different processes in a cell. An enzyme family of nine protein arginine methyltransferases catalyses the addition of methyl groups on arginines of histone and non-histone proteins, resulting in either mono- or dimethylated-arginine residues. The reversibility of histone modifications is an essential feature of epigenetic regulation to respond to changes in environmental factors, signalling events, or metabolic alterations. Prominent histone modifications like lysine acetylation and lysine methylation are reversible. Enzyme family pairs have been identified, with each pair of lysine acetyltransferases/deacetylases and lysine methyltransferases/demethylases operating complementarily to generate or erase lysine modifications. Several analyses also indicate a reversible nature of arginine methylation, but the enzymes facilitating direct removal of methyl moieties from arginine residues in proteins have been discussed controversially. Differing reports have been seen for initially characterized putative candidates, like peptidyl arginine deiminase 4 or Jumonji-domain containing protein 6. Here, we review the most recent cellular, biochemical, and mass spectrometry work on arginine methylation and its reversible nature with a special focus on putative arginine demethylases, including the enzyme superfamily of Fe(II) and 2-oxoglutarate-dependent oxygenases.     

Investigation of Sparse Data Mouse Imaging Using Micro-CT with a Carbon-Nanotube-Based X-ray Source

There has been a renewed interest in algorithm development for image reconstruction from highly incomplete data in computed tomography(CT).Such algorithms may lead to reduced imaging dose and time,and to the design of innovative configurations tailored to specific imaging tasks.In recent years,a carbon-nanotube(CNT)-based field-emission x-ray source has been developed,which offers easy electronic control of radiation and thus can be an ideal candidate for gated imaging.We have recently proposed algorithms f...     

Sugar transporters for intercellular exchange and nutrition of pathogens

Sugar efflux transporters are essential for the maintenance of animal blood glucose levels, plant nectar production, and plant seed and pollen development. Despite broad biological importance, the identity of sugar efflux transporters has remained elusive. Using optical glucose sensors, we identified a new class of sugar transporters, named SWEETs, and show that at least six out of seventeen Arabidopsis, two out of over twenty rice and two out of seven homologues in Caenorhabditis elegans, and the single copy human protein, mediate glucose transport. Arabidopsis SWEET8 is essential for pollen viability, and the rice homologues SWEET11 and SWEET14 are specifically exploited by bacterial pathogens for virulence by means of direct binding of a bacterial effector to the SWEET promoter. Bacterial symbionts and fungal and bacterial pathogens induce the expression of different SWEET genes, indicating that the sugar efflux function of SWEET transporters is probably targeted by pathogens and symbionts for nutritional gain. The metazoan homologues may be involved in sugar efflux from intestinal, liver, epididymis and mammary cells.     

Electron Spin Resonance Study of Fuel Cell Polymer Membrane Degradation

1 Introduction The long termstability of the membraneis ani mportant factor li mitingthe fuel cell lifeti me .During ex-tended use the membrane degrades , probably via reaction with hydroxyl and superoxide radicals which areregular intermediates of the oxygenreduction at the cathode .Only extremely stable membranes can withstandthe aggressive chemical and physical environment in an operating fuel cell . Within a given set of operatingconditions,intrinsic chemical and mechanical properties of t…     

Pluripotency of spermatogonial stem cells from adult mouse testis

Embryonic germ cells as well as germline stem cells from neonatal mouse testis are pluripotent and have differentiation potential similar to embryonic stem cells, suggesting that the germline lineage may retain the ability to generate pluripotent cells. However, until now there has been no evidence for the pluripotency and plasticity of adult spermatogonial stem cells (SSCs), which are responsible for maintaining spermatogenesis throughout life in the male. Here we show the isolation of SSCs from adult mouse testis using genetic selection, with a success rate of 27%. These isolated SSCs respond to culture conditions and acquire embryonic stem cell properties. We name these cells multipotent adult germline stem cells (maGSCs). They are able to spontaneously differentiate into derivatives of the three embryonic germ layers in vitro and generate teratomas in immunodeficient mice. When injected into an early blastocyst, SSCs contribute to the development of various organs and show germline transmission. Thus, the capacity to form multipotent cells persists in adult mouse testis. Establishment of human maGSCs from testicular biopsies may allow individual cell-based therapy without the ethical and immunological problems associated with human embryonic stem cells. Furthermore, these cells may provide new opportunities to study genetic diseases in various cell lineages.