Unsolved Issues (unsolved + issues)

Distribution by Scientific Domains


Selected Abstracts


Extracellular-regulated kinase,mitogen-activated protein kinase cascade: Unsolved issues

JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 5 2010
Jean-François L. Bodart
Abstract This review point out several aspects regarding the mitogen-activated protein kinase (MAPK)/extracellular-regulated kinase (Erk) network, which are still pending issues in the understanding how this pathway integrate information to drive cell fates. Focusing on the role of Erk during cell cycle, it has to be underlined that Erk downstream effectors, which are required for mitosis progression and contribute to aneuploidy during tumorigenesis, remain to be determined. In addition to the identity of the terminal enzymes or effectors of Erk, it has to be stressed that the dynamic nature of the Erk signal is itself a key factor in cell phenotype decisions. Development of biophotonics strategies for monitoring the Erk network at the spatiotemporal level in living cells, as well as computational and hypothesis-driven approaches, are called to unravel the principles by which signaling networks create biochemical and biological specificities. Finally, Erk dynamics might also be impacted by other post-translational modification than phosphorylation, such as O -GlcNAcylation. J. Cell. Biochem. 109: 850,857, 2010. © 2010 Wiley-Liss, Inc. [source]


Engineering of a monomeric and low-glycosylated form of human butyrylcholinesterase

FEBS JOURNAL, Issue 2 2002
Expression, characterization, crystallization, purification
Human butyrylcholinesterase (BChE; EC 3.1.1.8) is of particular interest because it hydrolyzes or scavenges a wide range of toxic compounds including cocaine, organophosphorus pesticides and nerve agents. The relative contribution of each N-linked glycan for the solubility, the stability and the secretion of the enzyme was investigated. A recombinant monomeric BChE lacking four out of nine N-glycosylation sites and the C-terminal oligomerization domain was stably expressed as a monomer in CHO cells. The purified recombinant BChE showed catalytic properties similar to those of the native enzyme. Tetragonal crystals suitable for X-ray crystallography studies were obtained; they were improved by recrystallization and found to diffract to 2.0 Å resolution using synchrotron radiation. The crystals belong to the tetragonal space group I422 with unit cell dimensions a = b = 154.7 Å, c = 124.9 Å, giving a Vm of 2.73 Å3 per Da (estimated 60% solvent) for a single molecule of recombinant BChE in the asymmetric unit. The crystal structure of butyrylcholinesterase will help elucidate unsolved issues concerning cholinesterase mechanisms in general. [source]


Phytoceuticals: Mighty but ignored weapons against Helicobacter pylori infection

JOURNAL OF DIGESTIVE DISEASES, Issue 3 2008
Sun-Young LEE
Helicobacter pylori (H. pylori) infection causes peptic ulcer disease, mucosa-associated lymphoid tissue (MALT) lymphomas and gastric adenocarcinomas, for which the pathogenesis of chronic gastric inflammation prevails and provides the pathogenic basis. Since the role of H. pylori infection is promoting carcinogenesis rather than acting as a direct carcinogen, as several publications show, eradication alone cannot be the right answer for preventing H. pylori -associated gastric cancer. Therefore, a non-antimicrobial approach has been suggested to attain microbe-associated cancer prevention through controlling H. pylori -related chronic inflammatory processes and mediators responsible for carcinogenesis. Phytoceutical is a term for plant products that are active on biological systems. Phytoceuticals such as Korean red ginseng, green tea, red wine, flavonoids, broccoli sprouts, garlic, probiotics and flavonoids are known to inhibit H. pylori colonization, decrease gastric inflammation by inhibiting cytokine and chemokine release, and repress precancerous changes by inhibiting nuclear factor-kappa B DNA binding, inducing profuse levels of apoptosis and inhibiting mutagenesis. Even though further unsolved issues are awaited before phytoceuticals are accepted as a standard treatment for H. pylori infection, phytoceuticals can be a mighty weapon for either suppressing or modulating the disease-associated footprints of H. pylori infection. [source]


Construction of statistical shape atlases for bone structures based on a two-level framework,

THE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 1 2010
Chenyu Wu
Abstract Background The statistical shape atlas is a 3D medical image analysis tool that encodes shape variations between populations. However, efficiency, accuracy and finding the correct correspondence are still unsolved issues during the construction of the atlas. Methods We developed a two-level-based framework that speeds up the registration process while maintaining accuracy of the atlas. We also proposed a semi-automatic strategy to achieve segmentation and registration simultaneously, without knowing any prior information about the shape. Results We have separately constructed the atlas for the femur and spine. The experimental results demonstrate the efficiency and accuracy of our methods. Conclusions Our two-level framework and semi-automatic strategy are able to efficiently construct the atlas for bone structures without losing accuracy. We can handle either 3D surface data or raw DICOM images. Copyright © 2009 John Wiley & Sons, Ltd. [source]


European Academy of Paediatrics Research in Ambulatory Setting network (EAPRASnet): a multi-national general paediatric research network for better child health

CHILD: CARE, HEALTH AND DEVELOPMENT, Issue 3 2010
S. Del Torso
Abstract Background In 2008, the European Academy of Paediatrics launched a paediatric-based research network , EAPRASnet (European Academy of Paediatrics Research in Ambulatory Setting network). The network has recruited primary care and general paediatricians from European and Mediterranean countries. Methods Every paediatrician joining the network has been asked to complete a recruitment survey. The aims of the survey were to characterize paediatrician's demographics, practice arrangements and patient's demographics, to define main incentives for research, and to learn what paediatricians view as unsolved issues that need to be studied. Results A total of 156 paediatricians from 19 countries were recruited with 144 completing the questionnaire (92%). Majority of respondents (89%) were general paediatricians for more than half of their time. Practice arrangement of 47% of paediatricians was solo practice, with 40% in group practice. Electronic medical records were being used by 72% of respondents. Over 70% of the paediatricians had more than 1000 patients under their clinical care, and patients younger than 6 years old contributed nearly half of the patient population. Areas of most interest for research were: quality of care indicators, communication with parents, obesity, attention deficit hyperactivity disorder and effective well child care. Main incentives for participation in a research project were interest in the topic (81%) and effort to improve quality of care (71%). Lack of time was the leading reported obstacle for research activity (72%). EAPRASnet is growing, and the network's structure, operation and funding are described. Methods for joining the network and the process of study development are presented. Conclusion A core group of EAP general paediatricians are committed to research in their practices. The information gathered will serve for future planning of research projects in the EAPRASnet to harmonize and optimize the care given to children in the primary care setting in Europe. [source]