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New Aspects (new + aspect)
Selected AbstractsChemInform Abstract: A New Aspect of Nickel-Catalyzed Grignard Cross-Coupling Reactions: Selective Synthesis, Structure, and Catalytic Behavior of a T-Shape Three-Coordinate Nickel(I) Chloride Bearing a Bulky NHC Ligand.CHEMINFORM, Issue 29 2010Satoshi Miyazaki Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] New Aspects of Impact Reactivity of Polynitro Compounds, Part III.PROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 6 2003Impact Sensitivity as a Function of the Imtermolecular Interactions Abstract Published data of impact sensitivity of 33 polynitro compounds detected by sound were expressed as the drop energy, Edr, required for 50 percent initiation probability. A logarithmic relationship has been found between the Edr values and heats of fusion of the said compounds. The relationship has been found to be in accordance with the idea concerning the role of plastic deformations of crystal played in the initiation of energetic materials by impact and shock. An analogous application of heats of sublimation has not given convincing results. [source] Thallium Halides , New Aspects of the Stereochemical Activity of Electron Lone Pairs of Heavier Main-Group ElementsCHEMINFORM, Issue 16 2007Anja-Verena Mudring Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] New Aspects in the Chemistry of Three-membered Ring Compounds Containing a Highly Coordinate Main Group ElementCHINESE JOURNAL OF CHEMISTRY, Issue 9 2005Kawashima Takayuki Abstract The title compounds were synthesized by taking advantage of the Martin ligand. Their structures were determined by X-ray crystallography. Pentacoordinate thiasiliranides were hydrolyzed to give the corresponding thiol. Pentacoordinate chalcogenaphosphiranes were found to have polar P-chalcogen bonds, which were confirmed by their reactions with CF 3SO3Me to give the corresponding 1-(methylchalcogena)alkylphosphonium triflates and by the solvent-dependent NMR studies. [source] New aspects concerning ulcerative colitis and colonic carcinoma: Analysis of levels of neuropeptides, neurotrophins, and TNFalpha/TNFreceptor in plasma and mucosa in parallel with histological evaluation of the intestineINFLAMMATORY BOWEL DISEASES, Issue 10 2008Malin Johansson MSc Abstract Background: The levels of neuropeptides, neurotrophins, and TNFalpha (TNF,)/TNF receptor in plasma and mucosa for patients with ulcerative colitis (UC) and colonic carcinoma, and concerning plasma also for healthy controls, were examined. Moreover, the relationships between the different substances and the influence of mucosal derangement on the levels were analyzed. Methods: The levels of VIP, SP, CGRP, BDNF, NGF, and TNF,/TNFreceptor1 were measured using ELISA/EIA. Results: Patients with UC demonstrated the highest levels of all analyzed substances in plasma, with the exception of BDNF. However, there were differences within the UC group, patients treated with corticosteroids, and/or nonsteroid antiinflammatory/immunosuppressive treatment having higher plasma levels than those not given these treatments. Patients with colonic carcinoma showed higher SP and TNFreceptor1 levels in plasma compared to healthy controls. Concerning mucosa, the levels of almost all analyzed substances were elevated for patients with UC compared to noncancerous mucosa of colonic carcinoma patients. There were correlations between many of the substances in both plasma and mucosa, especially concerning the 3 neuropeptides examined. There were also marked associations with mucosa derangement. Conclusions: Via analysis of correlations for the respective patients and via comparisons between the different patient groups, new and original information was obtained. Interestingly, the degree of mucosal affection was markedly correlated with tissue levels of the substances and the treatments were found to be of importance concerning plasma but not tissue levels of these. Combined plasma analysis of neuropeptides, neurotrophins, and TNFreceptor1 may help to distinguish UC and colonic carcinoma patients. (Inflamm Bowel Dis 2008) [source] New aspects of unsaturated polyester resin synthesis.POLYMER INTERNATIONAL, Issue 5 2003Part 2. Abstract The distribution of unsaturations in the prepolymer of a typical unsaturated polyester (UP) resin (maleic anhydride, phthalic anhydride and 1,2-propylene glycol) has been shown to influence the kinetics of the cure process with styrene monomer. Segments containing double bonds in close proximity appear to lower the reactivity of the resin due to steric hindrance, as indicated by the fact that the rate of cure and the final degree of cure, measured by differential scanning calorimetry (DSC), increase as the average sequence length (SL) of maleic units decreases. This implies that the reactivity of UP resins may be improved by synthesis of prepolymers with certain reactant sequence-length distributions. The copolymer formed by the melt condensation process of maleic anhydride, phthalic anhydride and 1,2-propylene glycol in the absence of a transesterification catalyst has a non-random structure with a tendency towards blockiness. This was established using 1H NMR analysis in tandem with deterministic and Monte Carlo modelling techniques. Copyright © 2003 Society of Chemical Industry [source] Proteomic analysis of the E2F1 response in p53-negative cancer cells: New aspects in the regulation of cell survival and deathPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 21 2006Zhenpeng Li Abstract E2F1 is an essential transcription factor that regulates cell-cycle progression and apoptosis. Overexpression of E2F1 sensitizes neoplastic cells to apoptosis and leads to tumor growth suppression, making it an interesting target for anticancer therapy. Use of E2F1 as a therapeutic, however, requires a detailed knowledge of the mechanisms by which it controls cellular proliferation and apoptosis, and of other potential E2F1 activities. In this study, a differential proteome analysis was performed to identify proteins associated with E2F1 activity in inducible p53-deficient Saos-2ERE2F1 osteosarcoma cells. 2-DE revealed a distinct protein profile at 32,h after E2F1 activation. Thirty-three proteins were reproducibly identified as either up-regulated or down-regulated. Proteins were identified by MALDI-MS. They included hitherto unknown E2F1 target proteins of cytoskeletal origin, chaperones, enzymes, proteasomal proteins, and several heterogeneous nuclear ribonucleoproteins, suggesting its role in the ER-stress response, protein degradation, and modulation of pre-mRNA splicing. Protein analysis-derived results were verified by Western blot using representative protein candidates. Thirteen identified proteins were the products of genes known to be cancer related. Thus, proteome analysis provides new information about the complexity of E2F1 activities in human cancer cells that may be considered when using E2F1 as a drug. [source] New aspects of IFN-,/, signalling in immunity, oncogenesis and bone metabolismCANCER SCIENCE, Issue 5 2003Akinori Takaoka Although interferons (IFNs) were originally identified as humoral factors that confer an antiviral state upon cells, they have been demonstrated to be multifunctional in a variety of biological systems. The IFN-,/, system modulates not only the cellular immune response to viral and bacterial infections, but also the oncogenic process and bone metabolism. Further studies have revealed additional unique facets of the IFN-,/, system. A weak signal by constitutively produced IFN-,/, is critical not only for the regulation of cellular amplification of IFN-,/, production upon viral infection or the enhancement of signalling by other cytokines, but also for the regulation of adaptive immune responses, such as the enhancement of CD8+ T cell activation. Furthermore, IFN-, signalling is critical for the regulation of the bone-resorbing osteo-clasts. In this review, we focus on the newly discovered roles of the IFN-,/, system in host defense and bone remodeling, particularly on the functions of the weak IFN-,/, signalling in the context of what we refer to as the "rewing-up" model. (Cancer Sci 2003; 94: 405,411) [source] 2162: New aspects of the Slug Mucosal Irritation (SMI) assay: Detecting ocular stinging, itching and burning sensationsACTA OPHTHALMOLOGICA, Issue 2010J LENOIR Purpose Our eyes are one of the most important senses. They are very sensitive and irritations may occur easily. A screening method for ocular discomfort would be very helpful in the development and refinement of formulations. In the past, the Slug Mucosal Irritation (SMI) assay demonstrated a relation between an increased mucus production (MP) in slugs and an elevated incidence of stinging, itching and burning (SIB) in human eyes. The aim of this study is to compare subjective ocular discomfort caused by shampoos evaluated in volunteers with results of the SIB-procedure. Methods The stinging potency of 1 artificial tear and 10 shampoos was evaluated with the SIB-procedure by placing 3 slugs per treatment group 3 times on 100 µl of the test item. After each 15 min contact period, MP was measured. Evaluation of the results is based upon the total MP during 3 repeated contact periods. Experiments were repeated 3 times. A Human Eye Irritation test with the same test items will be set up (12-period cross-over study, 24 volunteers, study approved by an independent Commission for Medical Ethics, associated with Ghent University Hospital). The participants are dripped 10 µl of a 5% or 10% shampoo dilution in water or the artificial tear in 1 eye, while in the other eye 10 µl of water is administered. The evaluation of the test substances is done both by participants and the ophthalmologist at several time points. Conclusion With the obtained results we will be able to improve the newly developed protocol and examine the predictability with reference to non- and mildly irritating formulations in humans. We hope to conclude that the SIB-procedure is a good tool to predict clinical ocular discomfort. [source] RESTRUCTURING THE NHS AGAIN: SUPPLY SIDE REFORM IN RECENT ENGLISH HEALTH CARE POLICYFINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 4 2009Pauline Allen Introducing market-like structures to public services is a key aspect of New Public Management. The restructuring of the NHS into an internal market of the 1990s is an example. Recent policies have further developed this notion. A new aspect of the restructuring is a focus on increasing the diversity of types of provider of healthcare organisations. The objectives of the restructuring policy entailing the increase in supply side diversity are examined, and the challenges raised by these changes are discussed. It is argued that the government is too optimistic about the benefits, and insufficiently concerned about possible undesirable consequences. [source] Pathogenesis of Helicobacter pylori InfectionHELICOBACTER, Issue 2004Paul Hofman ABSTRACT Research in the last year has provided new insights into the function of the the cag -associated type IV secretion system and the vacuolating toxin VacA. A quite new aspect was disclosed by the finding that Helicobacter pylori in Mongolian gerbils colonizes a very distinct topology in the gastric mucous layer, obviously providing optimal conditions for long-term survival. Further research activities focused on H. pylori ammonia and metal metabolism as well as on bacterial stress defence mechanisms. Differential expression of approximately 7% of the bacterial genome was found at low pH suggesting that H. pylori has evolved a multitude of acid-adaptive mechanisms. VacA was shown to interrupt phagosome maturation in macrophage cell lines as well as to modulate and interfere with T lymphocyte immunological functions. Gastric mucosa as well as the H. pylori -infected epithelial cell line AGS strongly express IL-8 receptor A and B, which might contribute to the augmentation of the inflammatory response. Accumulating evidence implicates genetic variation in the inflammatory response to H. pylori in the etiology of the increased risk of gastric cancer after H. pylori infection. The chronic imbalance between apoptosis and cell proliferation is the first step of gastric carcinogenesis. In this regard, it was demonstrated that coexpression of two H. pylori proteins, CagA and HspB, in AGS cells, caused an increase in E2F transcription factor, cyclin D3, and phosphorylated retinoblastoma protein. Taken together, we now have a better understanding of the role of different virulence factors of H. pylori. There is still a lot to be learned, but the promising discoveries summarized here, demonstrate that the investigation of the bacterial survival strategies will give novel insights into pathogenesis and disease development. [source] Fire disturbance disrupts co-occurrence patterns of terrestrial vertebrates in Mediterranean woodlandsJOURNAL OF BIOGEOGRAPHY, Issue 5 2006Maurizio Sarŕ Abstract Aim, This paper uses null model analysis to explore the pattern of species co-occurrence of terrestrial vertebrate fauna in fire-prone, mixed evergreen oak woodlands. Location, The Erico,Quercion ilicis of the Mediterranean belt (50,800 m a.s.l.) in the Madonie mountain range, a regional park in northern Sicily (37°50, N, 14°05, E), Italy. Methods, The stratified sampling of vertebrates in a secondary succession of recent burned areas (BA, 1,2 years old), intermediate burned areas (INT, 4,10 years old) and ancient burned areas (CNB, > 50 years old), plus forest fragments left within burned areas (FF, 1,2 years old) permitted the comparison of patterns of species co-occurrence using a set of separate presence/absence matrices. First, the breeding avifauna derived from standardized point counts was analysed using Stone & Roberts'C -score, and by a null model algorithm (fixed/equiprobable). Secondly, the analysis was repeated using all vertebrate species recorded in the succession. Results, Sixty-five species were recorded in the 2-year study period in the four sample treatments. Birds were found to make up the largest component (63%) of the recorded assemblage. The BA treatment had the lowest species richness, followed in order by the small, medium and large FFs, and then by the CNBs. For both analyses (birds and total vertebrates), the C -scores were quite small and not significantly different from those that could be expected by chance in the BA and INT burned areas; this indicates a random co-occurrence among vertebrates of those assemblages. Contrariwise, for both analyses in the CNBs, the C -scores were large and significantly different from the simulated indices, thereby indicating a non-random co-occurrence pattern (segregation) of vertebrates in the undisturbed woodlands. In addition, C -score values for the surviving FFs show a significant aggregation of species. Main conclusions, The null model analyses highlighted a new aspect of fire disturbance in Mediterranean woodland ecosystems: the disruption in patterns of co-occurrence in the terrestrial vertebrate community. Wildfire alters community organization, inducing, for at least 10 years, a random aggregate of species. Communities re-assemble themselves, showing the occurrence of species segregation at least 50 years after fire. [source] Numerical solution of the free-surface viscous flow on a horizontal rotating elliptical cylinderNUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS, Issue 4 2008Roland Hunt Abstract The numerical solution of the free-surface fluid flow on a rotating elliptical cylinder is presented. Up to the present, research has concentrated on the circular cylinder for which steady solutions are the main interest. However, for noncircular cylinders, such as the ellipse, steady solutions are no longer possible, but there will be periodic solutions in which the solution is repeated after one full revolution of the cylinder. It is this new aspect that makes the investigation of noncircular cylinders novel. Here we consider both the time-dependent and periodic solutions for zero Reynolds number fluid flow. The numerical solution is expedited by first mapping the fluid film domain onto a rectangle such that the position of the free-surface is determined as part of the solution. For the time-dependent case a simple time-marching method of lines approach is adopted. For the periodic solution the discretised nonlinear equations have to be solved simultaneously over a time period. The resulting large system of equations is solved using Newton's method in which the form of the Jacobian enables a straightforward decomposition to be implemented, which makes matrix inversion manageable. In the periodic case all derivatives have been approximated pseudospectrally with the time derivative approximated by a differentiation matrix which has been specially derived so that the weight of fluid is algebraically conserved. Of interest is the solution for which the weight of fluid is at its maximum possible value, and this has been obtained by increasing the weight until a consistency break-down occurs. Time-dependent solutions do not produce the periodic solution after a long time-scale but have protuberances which are constantly appearing and disappearing. Periodic solutions exhibit spectral accuracy solutions and maximum supportable weight solutions have been obtained for ranges of eccentricity and angular velocity. The maximum weights are less than and approximately proportional to those obtained for the circular case. The shapes of maximum weight solutions is distinctly different from sub-maximum weight solutions. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2008 [source] Exomphalos , a major or minor problem?PEDIATRIC ANESTHESIA, Issue 9 2002T. O'Neill Introduction The mortality and morbidity statistics associated with exomphalos major remain discouraging despite advances in management techniques (1). Congenital lung pathology, in particular pulmonary hypoplasia, and thoracic maldevelopment, have been strongly allied to this condition, accounting for the high incidence of pulmonary insufficiency necessitating prolonged ventilatory support in these infants (2). We discuss the respiratory issues in an infant with a particularly severe form of exomphalos major, and the impact of a comprehensive parental website devoted to the infants' management and progress. Case Report A female infant, born at 38 weeks' gestation, was referred for management of exomphalos major. Due to the extensive nature of the abdominal wall defect, primary surgical closure was impossible and initial management consisted of staged reduction by external compression of the exomphalos. This resulted in escalating cardiovascular and respiratory embarrassment, and was abandoned in favour of conservative treatment, whereby the sac was dressed and allowed to epithelialise. Thereafter the clinical course was characterised by chronic pulmonary insufficiency requiring prolonged ventilatory support. Ventilator dependence did not significantly decrease until lung growth occurred and the sitting position was adopted, enabling weaning from conventional ventilation to genuine BIPAP at 6 months. Currently, after 11 months, we are preparing her for entry into a home ventilation programme. Throughout this period, progress and realistic goals were discussed at multidisciplinary case conferences involving the parents. The interpreted medical management has subsequently been displayed by the parents on an elaborate, up-to-date website, which is part of a larger ,Mother Of Omphalocele' network. Although innovative, this highlights the fact that we the medical profession, should be vigilant with regard to potential public exposure of patient management. Whilst the Internet has become an integral part of our own continuing education, this case highlights a new aspect of how it may be used by our patients and their relatives to compare and contrast management policies in various institutions. [source] The national innovation system and foreign R&D: the case of TaiwanR & D MANAGEMENT, Issue 5 2007Shin-Horng Chen R&D internationalization has increasingly involved countries outside the developed world. In addition, there has been a growing trend for countries in East Asia to seek to attract the R&D facilities of multinationals (MNCs). For such countries, they are faced with a fundamental question as to what kinds of impact MNCs' offshore R&D facilities will have on their own countries, especially in terms of technological innovation and industrial development. Set against the above backdrop, this paper sets out to examine a relatively new aspect of R&D internationalization related to global innovation networks and to open up the blackbox of the spillover effect regarding foreign R&D by examining the interplay of foreign R&D and Taiwan's national innovation system. The empirical part of the paper draws mainly upon intensive case studies of four high-profile foreign R&D facilities in the IT industry. The way foreign R&D interplays with Taiwan's NIS is examined in terms of the market & technology linkages. [source] Intermolecular interaction studies of winter flounder antifreeze protein reveal the existence of thermally accessible binding stateBIOPOLYMERS, Issue 2 2004Dat H. Nguyen Abstract The physical nature underlying intermolecular interactions between two rod-like winter flounder antifreeze protein (AFP) molecules and their implication for the mechanism of antifreeze function are examined in this work using molecular dynamics simulations, augmented with free energy calculations employing a continuum solvation model. The energetics for different modes of interactions of two AFP molecules is examined in both vacuum and aqueous phases along with the water distribution in the region encapsulated by two antiparallel AFP backbones. The results show that in a vacuum two AFP molecules intrinsically attract each other in the antiparallel fashion, where their complementary charge side chains face each other directly. In the aqueous environment, this attraction is counteracted by both screening and entropic effects. Therefore, two nearly energetically degenerate states, an aggregated state and a dissociated state, result as a new aspect of intermolecular interaction in the paradigm for the mechanism of action of AFP. The relevance of these findings to the mechanism of function of freezing inhibition in the context of our work on Antarctic cod antifreeze glycoprotein (Nguyen et al., Biophysical Journal, 2002, Vol. 82, pp. 2892,2905) is discussed. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004 [source] Reaction of 2,3-dihydro-1,5-benzothiazepines and phenylacetyl chloride in the presence of triethylamine: A new aspect on the formation mechanism of dihydro-1,3-oxazin-4-one derivatives,CHINESE JOURNAL OF CHEMISTRY, Issue 9 2004Jia-Xi Xu Abstract 2a,CDisubstituted 2,2a,3,4-tetrahydro-2-phenyl-1H -azeto[2,1- d][1,5]benzothiazepin-1-ones, as well as 2-substituted 2.3-dihydro-3-phenylacetyl-2-styryl-benzothiazoles and 4a,6-disubstituted 3-benzyl-4a,5-dihydro-2-phenyl1-H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-l-ones, were obtained from the reaction of 2,4-disubstituted 2,3dihydro-1,5-benzothiazepines with phenylacetyl chloride in the presence of triethylamine. The mechanism for the formation of 4a,5-dihydro-1H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-1-ones, 2,3-dihydro-1,3-oxazin-4-one derivatives, was suggested. [source] Hypocretin/orexin in fish physiology with emphasis on zebrafishACTA PHYSIOLOGICA, Issue 3 2010P. Panula Abstract One hypocretin/orexin (hcrt) gene has been identified in several fish species. The first pufferfish gene was identified in 2002 and the zebrafish gene was cloned in 2004. Its structure is very similar to that of mammals, and it encodes for two active peptides with C-termini similar to those of mammals. The gene is expressed in the brain in only one hypothalamic nucleus, which sends projections to the telencephalon, diencephalon, mesencephalon and rhombencephalon. The terminal fibres are found in close contact with many aminergic cell groups, including those of raphe serotonergic, locus coeruleus noradrenergic, several dopaminergic cell groups and the sole histaminergic hypothalamic cluster. One receptor corresponding to mammalian hcrt 2 receptor has been identified in fish. Overexpression of hcrt in zebrafish has been reported to consolidate wakefulness and inhibit rest. On the other hand, fish lacking the hcrt receptor show short and fragmented sleep instead of sleepiness and cataplexy. Food deprivation increases hcrt mRNA expression in zebrafish brain, and intracerebroventricular hcrt peptides stimulate food consumption and feeding behaviour in goldfish. Hcrt peptides thus have important roles in fish physiology. Many genetic and functional methods available render fish, especially zebrafish, a suitable organism to study new aspects of hcrt physiology in vertebrates. [source] A new look at an old visual system: structure and development of the compound eyes and optic ganglia of the brine shrimp artemia salina linnaeus, 1758 (branchiopoda, anostraca)DEVELOPMENTAL NEUROBIOLOGY, Issue 2 2002Miriam Wildt Abstract Compared to research carried out on decapod crustaceans, the development of the visual system in representatives of the entomostracan crustaceans is poorly understood. However, the structural evolution of the arthropod visual system is an important topic in the new debate on arthropod relationships, and entomostracan crustaceans play a key role in this discussion. Hence, data on structure and ontogeny of the entomostracan visual system are likely to contribute new aspects to our understanding of arthropod phylogeny. Therefore, we explored the proliferation of neuronal stem cells (in vivo incorporation of bromodeoxyuridine) and the developmental expression of synaptic proteins (immunohistochemistry against synapsins) in the developing optic neuropils of the brine shrimp Artemia salina Linnaeus, 1758 (Crustacea, Entomostraca, Branchiopoda, Anostraca) from hatching to adulthood. The morphology of the adult visual system was examined in serial sections of plastic embedded specimens. Our results indicate that the cellular material that gives rise to the visual system (compound eyes and two optic ganglia) is contributed by the mitotic activity of neuronal stem cells that are arranged in three band-shaped proliferation zones. Synapsin-like immunoreactivity in the lamina ganglionaris and the medulla externa initiated only after the anlagen of the compound eyes had already formed, suggesting that the emergence of the two optic neuropils lags behind the proliferative action of these stem cells. Neurogenesis in A. salina is compared to similar processes in malacostracan crustaceans and possible phylogenetic implications are discussed. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 117,132, 2002 [source] Granular cell tumors of the esophagus: report of five cases and review of diagnostic and therapeutic techniquesDISEASES OF THE ESOPHAGUS, Issue 5 2007L. De Rezende SUMMARY., Granular cell tumors (GCT) of the esophagus are stromal lesions originating from the Schwann cells of the submucosal neuronal plexus. Although they are very infrequent, they constitute the second largest cause of non-epithelial tumors in the esophagus after leiomyomas. These tumors are generally benign, although a certain number of malignant, aggressive cases have been reported. Diagnosis requires that this possibility be ruled out before deciding on which course of therapeutic action to take as well as familiarization with the relevant indicators. GCT linked synchronically or metachronically to other malignant neoplasias of the esophagus have also been described, but the actual extent of this association is uncertain. This report describes five cases of GCT recently diagnosed as incidental findings following endoscopic exploration. All of these were benign and were treated conservatively. The article discusses new aspects relating to the diagnosis of these lesions and the role carried out by endoscopic ultrasonography in their characterization, both at preliminary diagnosis and monitoring levels. No standard therapeutic guidelines exist for the management of GCT, but endoscopic treatment without invading the muscularis propria layer would be used for symptomatic patients, creating histopathological doubts requiring research on the entire organ. Endoscopic therapeutic techniques are analyzed (resection with forceps or diathermy handles, yttrium-aluminum-garnet laser ablation, alcohol injection) in esophageal GCT, which have overtaken surgery in most cases due to their efficiency, greater safety and fewer complications. [source] Emerging topics in Reelin functionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2010Eckart Förster Abstract Reelin signalling in the early developing cortex regulates radial migration of cortical neurons. Later in development, Reelin promotes maturation of dendrites and dendritic spines. Finally, in the mature brain, it is involved in modulating synaptic function. In recent years, efforts to identify downstream signalling events induced by binding of Reelin to lipoprotein receptors led to the characterization of novel components of the Reelin signalling cascade. In the present review, we first address distinct functions of the Reelin receptors Apoer2 and Vldlr in cortical layer formation, followed by a discussion on the recently identified downstream effector molecule n-cofilin, involved in regulating actin cytoskeletal dynamics required for coordinated neuronal migration. Next, we discuss possible functions of the recently identified Reelin,Notch signalling crosstalk, and new aspects of the role of Reelin in the formation of the dentate radial glial scaffold. Finally, progress in characterizing the function of Reelin in modulating synaptic function in the adult brain is summarized. The present review has been inspired by a session entitled ,Functions of Reelin in the developing and adult hippocampus', held at the Spring Hippocampal Research Conference in Verona/Italy, June 2009. [source] New developments in our understanding of acne pathogenesis and treatmentEXPERIMENTAL DERMATOLOGY, Issue 10 2009Ichiro Kurokawa Abstract:, Interest in sebaceous gland physiology and its diseases is rapidly increasing. We provide a summarized update of the current knowledge of the pathobiology of acne vulgaris and new treatment concepts that have emerged in the last 3 years (2005,2008). We have tried to answer questions arising from the exploration of sebaceous gland biology, hormonal factors, hyperkeratinization, role of bacteria, sebum, nutrition, cytokines and toll-like receptors (TLRs). Sebaceous glands play an important role as active participants in the innate immunity of the skin. They produce neuropeptides, excrete antimicrobial peptides and exhibit characteristics of stem cells. Androgens affect sebocytes and infundibular keratinocytes in a complex manner influencing cellular differentiation, proliferation, lipogenesis and comedogenesis. Retention hyperkeratosis in closed comedones and inflammatory papules is attributable to a disorder of terminal keratinocyte differentiation. Propionibacterium acnes, by acting on TLR-2, may stimulate the secretion of cytokines, such as interleukin (IL)-6 and IL-8 by follicular keratinocytes and IL-8 and -12 in macrophages, giving rise to inflammation. Certain P. acnes species may induce an immunological reaction by stimulating the production of sebocyte and keratinocyte antimicrobial peptides, which play an important role in the innate immunity of the follicle. Qualitative changes of sebum lipids induce alteration of keratinocyte differentiation and induce IL-1 secretion, contributing to the development of follicular hyperkeratosis. High glycemic load food and milk may induce increased tissue levels of 5,-dihydrotestosterone. These new aspects of acne pathogenesis lead to the considerations of possible customized therapeutic regimens. Current research is expected to lead to innovative treatments in the near future. [source] Vitamin D and skin: new aspects for dermatologyEXPERIMENTAL DERMATOLOGY, Issue 2004Bodo Lehmann Abstract:, It has been shown that epidermal keratinocytes have the capacity for the UVB-induced photochemical conversion of 7-dehydrocholesterol to vitamin D3, and also for the enzymatically controlled hydroxylation of the photolysis product. This metabolic loop results in the formation of the biologically active final product 1,,25-dihydroxyvitamin D3 (1,,25(OH)2D3, calcitriol). The epidermal synthesis of calcitriol is of fundamental relevance because calcitriol regulates important cellular functions in keratinocytes and immunocompetent cells. Because of their anti-proliferative and prodifferentiating effects, calcitriol and other vitamin D analogs are highly efficient in the treatment of psoriasis vulgaris. In addition, the known therapeutic effect of UVB light therapy in the treatment of psoriasis may, at least in part, be mediated via UVB-induced synthesis of calcitriol. Increasing evidence now indicates that cutaneous vitamin D synthesis is of great importance for the prevention of a broad variety of diseases, including various malignancies. It has been postulated that cancer mortality could be reduced via careful UV exposure or, more safely, via oral substitution with vitamin D. These new findings must be taken into account when establishing new sun protection guidelines for the prevention of skin cancer. In addition, better understanding of the metabolism of vitamin D in the skin has opened up new perspectives for the therapeutic application of vitamin D analogs, e.g. in inflammatory skin diseases. [source] Physico-chemical properties of molten dimer ascorbate oxidaseFEBS JOURNAL, Issue 22 2006Eleonora Nicolai The possible presence of dimeric unfolding intermediates might offer a clue to understanding the relationship between tertiary and quaternary structure formation in dimers. Ascorbate oxidase is a large dimeric enzyme that displays such an intermediate along its unfolding pathway. In this study the combined effect of high pressure and denaturing agents gave new insight on this intermediate and on the mechanism of its formation. The transition from native dimer to the dimeric intermediate is characterized by the release of copper ions forming the tri-nuclear copper center located at the interface between domain 2 and 3 of each subunit. This transition, which is pH-dependent, is accompanied by a decrease in volume, probably associated to electrostriction due to the loosening of intra-subunit electrostatic interactions. The dimeric species is present even at 3 × 108 Pa, providing evidence that mechanically or chemically induced unfolding lead to a similar intermediate state. Instead, dissociation occurs with an extremely large and negative volume change (,V , ,200 mL·mol,1) by pressurization in the presence of moderate amounts of denaturant. This volume change can be ascribed to the elimination of voids at the subunit interface. Furthermore, the combination of guanidine and high pressure uncovers the presence of a marginally stable (,G , 2 kcal·mol,1) monomeric species (which was not observed in previous equilibrium unfolding measurements) that might be populated in the early folding steps of ascorbate oxidase. These findings provide new aspects of the protein folding pathway, further supporting the important role of quaternary interactions in the folding strategy of large dimeric enzymes. [source] Consistency of the spatial autocorrelation method with seismic interferometry and its consequenceGEOPHYSICAL PROSPECTING, Issue 3 2008Toshiaki Yokoi ABSTRACT We have cross-checked the conventional theory of the spatial autocorrelation method and the consequence of seismic interferometry: the retrieval of the elastodynamic Green's function. Their mutual consistency is almost complete. The basic formulas of the conventional spatial autocorrelation theory can be derived by an alternative approach based on the retrieval of the elastodynamic Green's function. The only discrepancy is found with the average of the complex coherence function over azimuth in a wavefield dependent on azimuth. It is hypothesized, in discussion, that this discrepancy is due to the way of representing the wavefield in the background theory of seismic interferometry that can produce only wavefields moderately dependent on azimuth and that the mentioned consequence of seismic interferometry can also only make sense in a wavefield moderately dependent on azimuth. Our field experiment with a wavefield dependent on azimuth showed that the consequence of seismic interferometry in the logical framework of the conventional spatial autocorrelation theory is appropriate under such degrees of approximation as the measure proposed in this study, i.e., the deviation of the total dispersion curves is between about 10 and 16 per cent at the maximum from those averaged over azimuth. The acceptance of the retrieval of Green's function gives a proper physical meaning to the complex coherence function: the real part of the elastodynamic Green's function normalized by its zero-offset version. This makes it possible to take a deterministic approach rather than the statistical one on which the conventional spatial autocorrelation method is based and gives fruitful new aspects and perspectives. For example, the formula for the multi-mode case is given and the possibility of exploration of two or three dimensional velocity structures is suggested. [source] Virion half-life in chronic hepatitis B infection is strongly correlated with levels of viremia,HEPATOLOGY, Issue 4 2008Maura Dandri Analysis of hepatitis B virus (HBV) kinetics with mathematical models may disclose new aspects of HBV infection and host response mechanisms. To determine the kinetics of virion decay from the blood of patients in different phases of chronic infection, we applied mathematical modeling to real-time polymerase chain reaction assays, which enable quantification of viremia and intrahepatic HBV productivity by measuring both copy number and activity of covalently closed circular DNA (relaxed circular DNA/covalently closed circular DNA) in the liver of 80 untreated chronically active HBV carriers (38 hepatitis B e antigen [HBeAg]-positive and 42 HBeAg-negative individuals). We found that the half-life of circulating virions is very fast (median 46 and 2.5 minutes in HBeAg-positive and HBeAg-negative individuals, respectively) and strongly related to viremia, with clearance rates significantly accelerating as viral loads decrease. To investigate whether immune components can influence the kinetics of virion decay, we analyzed viral dynamics in immunodeficient urokinase-type plasminogen activator chimera mice. Virion half-life in mice (range, 44 minutes to >4 hours) was comparable to estimates determined in high viremic carriers, implying that clearance rates in these patients are mostly determined by common nonspecific mechanisms. Notably, the lack of correlation between virion half-life and viremia in mice indicated that immune components significantly accelerate virion clearance rates in individuals with low titers. Conclusion: Our analyses suggest that both host defense mechanisms and levels of circulating virions affect the kinetics of HBV decay assessed in the serum of chronic carriers. Identification of the factors affecting clearance rates will be important for future antiviral drug developments and it may give insights into the mechanisms involved in clearance of other chronic infections, such as human immunodeficiency virus and hepatitis C virus. (HEPATOLOGY 2008.) [source] Cord blood banking: ethical and cost,benefit aspectsISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue 1 2007S. Querol Cord blood represents a new source of stem cells on the edge of fetal and postnatal life. Increasing interest in stem cell therapy has moulded cord blood banking scope, evolving to a multidisciplinary platform exceeding the classic field of haemotherapy. This review intends to re-analyse this and presents the new aspects of cord blood banking that direct it to a model of cell pharmacy in a globalized world. [source] Research for d eterminant factors and features of emotional responses of "kandoh" (the state of being emotionally moved)JAPANESE PSYCHOLOGICAL RESEARCH, Issue 4 2003Akihiko Tokaji Abstract: The feature and determinants of the emotional response kandoh (the state of being emotionally moved) were positively examined (kandoh has rarely been made the object of research in the field of psychology). First, the author reviewed the research done so far and summarized the features of kandoh, and the structural model of the process leading to kandoh was introduced from the results of the above research. Furthermore, experimental examination about the model was performed of different types of stories, and even stories with opposing the emotional frameworks of happiness or sadness, both were shown that they were able to become heart-warming good stories. Moreover, it was shown that the event-related knowledge was important for evocation of kandoh. From the experiment results, consideration was made about new aspects of kandoh. [source] Antiproliferative activity of CCN3: Involvement of the C-terminal module and post-translational regulation,JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2007A.M. Bleau Abstract Previous work had suggested that recombinant CCN3 was partially inhibiting cell proliferation. Here we show that native CCN3 protein secreted into the conditioned medium of glioma transfected cells indeed induces a reduction in cell proliferation. Large amounts of CCN3 are shown to accumulate both cytoplasmically and extracellularly as cells reach high density, therefore highlighting new aspects on how cell growth may be regulated by CCN proteins. Evidence is presented establishing that the amount of CCN3 secreted into cell culture medium is regulated by post-translational proteolysis. As a consequence, the production of CCN3 varies throughout the cell cycle and CCN3 accumulates at the G2/M transition of the cycle. We also show that CCN3-induced inhibition of cell growth can be partially reversed by specific antibodies raised against a C-terminal peptide of CCN3. The use of several clones expressing various portions of CCN3 established that the CT module of CCN3 is sufficient to induce cell growth inhibition. J. Cell. Biochem. 101: 1475,1491, 2007. © 2007 Wiley-Liss, Inc. [source] Two-Sided Platforms: Product Variety and Pricing StructuresJOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 4 2009Andrei Hagiu This paper provides a new modeling framework to analyze two-sided platforms connecting producers and consumers. In contrast to the existing literature, indirect network effects are determined endogenously, through consumers' taste for variety and producer competition. Three new aspects of platform pricing structures are derived.,First, the optimal platform pricing structure shifts towards extracting more rents from producers relative to consumers when consumers have stronger demand for variety, since producers become less substitutable. With platform competition, consumer preferences for variety, producer market power, and producer economies of scale in multihoming also make platforms' price-cutting strategies on the consumer side less effective. This second effect on equilibrium pricing structures goes in the opposite direction relative to the first one.,Third, variable fees charged to producers can serve to trade off producer innovation incentives against the need to reduce a platform holdup problem. [source] | ||||||||||||||||||||||||||||||||||