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Kinds of Furthermore Selected AbstractsBehavioural observations of Pieris brassicae larvae indicate multiple mechanisms of action of analogous drimane antifeedantsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2000L. Messchendorp Abstract We tested 11 analogous synthetic drimane antifeedant compounds for their feeding inhibiting effects on larvae of the large white butterfly Pieris brassicae L. (Lepidoptera: Pieridae) in no-choice tests on the host plant Brassica oleracea L. Furthermore, we observed larval feeding behaviour in no-choice tests to analyze temporal effects of five drimanes. The results show that the five analogous antifeedants differentially influence feeding behaviour and locomotion activity. Warburganal and polygodial are most likely sensory mediated antifeedants. Habituation to these compounds occurs soon after the onset of the tests (i.e., within 0.5,1.5 h). Compound 5 and confertifolin are probably not direct, sensory mediated antifeedants. After 0.5,1.5 h of exposure, these compounds inhibit not only feeding, but also locomotion behaviour, indicating postingestive, toxic effects. Isodrimenin inhibits feeding from the onset of the test and is probably a sensory mediated antifeedant. No habituation occurs to this compound, indicating that isodrimenin is either a very strong antifeedant or that it additionally has postingestive, toxic effects. Topical application of the drimanes on the larval cuticle revealed feeding inhibiting effects, but these could not be related to the occurrence of postingestive feeding inhibiting effects, indicating that this method is inappropriate to show possible postingestive effects of drimanes in P. brassicae. In conclusion, the behavioural observations performed in this research indicate that analogous drimanes inhibit feeding by P. brassicae larvae through multiple mechanisms of action. The results show that, when developing a structure activity relationship (SAR) for a series of antifeedants, it is important to distinguish the mode of action which underlies inhibition of feeding. [source] The recent breakthroughs in the understanding of host genomics in hepatitis CEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 10 2010Andri Rauch Eur J Clin Invest 2010; 40 (10): 950,959 Abstract Background, Hepatitis C Virus (HCV) infection is spontaneously resolved in about 30% of acutely infected individuals. In those who progress to chronic hepatitis C, HCV therapy permanently eradicates infection in about 40% of cases. It has long been suspected that host genetic factors are key determinants for the control of HCV infection. Design, We will review in this study four genome-wide association studies (GWAS) and two large candidate gene studies that assessed the role of host genetic variation for the natural and treatment-induced control of HCV infection. Results, The studies consistently identified genetic variation in interleukin 28B (IL28B) as the strongest predictor for the control of HCV infection. Importantly, single nucleotide polymorphisms (SNPs) in IL28B strongly predicted both spontaneous and treatment-induced HCV recovery. IL28B is located on chromosome 19 and encodes interferon-,, a type III interferon with antiviral activity, which is mediated through the JAK-STAT pathway by inducing interferon-stimulated genes. The SNPs identified in the GWAS are in high linkage disequilibrium with coding or functional non-coding SNPs that might modulate function and/or expression of IL28B. The role of the different IL28B alleles on gene expression and cytokine function has not yet been established. Conclusions, These findings provide strong genetic evidence for the influence of interferon-, for both the natural and treatment-induced control of HCV infection, and support the further investigation of interferon-, for the treatment of chronic hepatitis C. Furthermore, genetic testing before HCV therapy could provide important information towards an individualized HCV treatment. [source] BSc2118 is a novel proteasome inhibitor with activity against multiple myelomaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 2 2010Jan Sterz Abstract Objectives:, The ubiquitin,proteasome system emerged as a new therapeutic target in cancer treatment. The purpose of this study was to elucidate the effects of the novel proteasome inhibitor BSc2118 on t(4;14) positive and negative multiple myeloma (MM) cells and normal peripheral blood mononuclear cells (PBMNC). Methods:, Human MM cell lines OPM-2, RPMI-8226, and U266 and primary MM cells from bone marrow aspirates were exposed to BSc2118. Cytotoxicity levels were evaluated using the MTT-test. BSc2118-induced apoptosis was analyzed by annexin-V assay. Further methods used included proteasomal activity determination, cell cycle analysis, western blot, and transcription factor assays. Results:, In OPM-2, RPMI-8226, U266 cell lines and primary MM cells, BSc2118 caused dose-dependent growth inhibitory effects. After 48 h, dose-dependent apoptosis occurred both in cell lines and primary myeloma cells irrespective of t(4;14). A significant G2-M cell cycle arrest occurred after 24 h. Furthermore, we observed a marked inhibition of intracellular proteasome activity, an increase in intracellular p21 levels, and an inhibition of NF-,B activation. The toxicity against PBMNC remained low, suggesting a broad therapeutic range of this agent. Conclusion:, Taken together, BSc2118 shows significant antimyeloma activity and may be considered as a promising agent in cancer drug development. [source] Functional Characterisation of the Volume-Sensitive Anion Channel in Rat Pancreatic ,-CellsEXPERIMENTAL PHYSIOLOGY, Issue 2 2001L. Best The whole-cell and perforated patch configurations of the patch-clamp technique were used to characterise the volume-sensitive anion channel in rat pancreatic ,-cells. The channel showed high permeability (P) relative to Cl, to extracellular monovalent organic anions (PSCN/PCll= 1.73, Pacetate/PCll= 0.39, Plactate/PCll= 0.38, Pacetoacetate/PCll= 0.32, Pglutamate/PCll= 0.28) but was less permeable to the divalent anion malate (Pmalate/PCll= 0.14). Channel activity was inhibited by a number of putative anion channel inhibitors, including extracellular ATP (10 mM), 1,9-dideoxyforskolin (100 ,M) and 4-OH tamoxifen (10 ,M). Inclusion of the catalytic subunit of protein kinase A in the pipette solution did not activate the volume-sensitive anion channel in non-swollen cells. Furthermore, addition of 8-bromoadenosine 3,,5,-cyclic monophosphate (8-BrcAMP) or forskolin failed to activate the channel in intact cells under perforated patch conditions. Addition of phorbol 12,13-dibutyrate (200 nM), either before or after cell swelling, also failed to affect channel activation. Our findings do not support the suggestion that the volume-sensitive anion channel in pancreatic ,-cells can be activated by protein kinase A. Furthermore, the ,-cell channel does not appear to be subject to regulation via protein kinase C. [source] Aurora C is directly associated with Survivin and required for cytokinesisGENES TO CELLS, Issue 6 2005Xiaomei Yan Much recent attention has been focused on Aurora C, the third member of the mammalian Aurora kinases family that plays significant roles in mitosis. We report here that using sensitive RT-PCR to amplify the C-terminal, we found that Aurora C is not only expressed highly in testis, but also among 16 other human tissues in a broad-spectrum way. Aurora C, as a chromosomal passenger protein, is co-localized with Aurora B and Survivin in mitotic cells. Aurora C can also be associated with Aurora B and Survivin in vivo and directly binds to Survivin but not Aurora B in vitro. Over-expression of a catalytically inactive mutant of Aurora C impaired the localization of Aurora C to the spindle midzone and severely disturbed the cytokinesis, resulting in multinucleation, all of which are consistent with the results induced by the mutant of Aurora B. Furthermore, we provide evidence that Aurora C could rescue the multinucleate phenotype produced by Aurora B mutant, and vice versa. Overall, these findings demonstrate that Aurora C, a member of the chromosomal passenger complex, is required for cytokinesis. [source] Increase of granzyme B-positive cells in ascitic fluid of patients with spontaneous bacterial peritonitisHEPATOLOGY RESEARCH, Issue 4 2008Alessandro Perrella Spontaneous bacterial peritonitis (SBP) occurs as a direct consequence of bacteria entering ascitic fluid (AF) from the intestinal lumen trough in several ways, including the hematogenous and mesenteric lymph nodes route. There are few studies on the cytokine profile of ascitic-derived mononuclear cells of patients with SBP, particularly on granzyme B (GZB). The aim of the present study was to verify whether patients with SBP have GZB-positive cells, whether they are increased in patients with aseptic ascites, and their trend after antibiotic treatment. We enrolled 36 consecutive patients (24 males and 12 females) with SBP on histologically-proven hepatitis C virus cirrhosis (group A) and 20 patients (11 males and nine females with ascites, but without evidences of SBP (group B). The diagnosis of SBP was made according to the following criteria: positive colture in AF or blood (at least two cultures) and neutrophils in AF (>250 mL polymorphonuclear leukocytes). For these patients we used ELISpot to assay GZB production on purified mononuclear cells in ascitesand peripheral blood, coupled with tumor necrosis factor-, tested using ELISA. A non-parametric statistical analysis was used to assess significant differences and correlations. We found positive culture in all of the patients with SBP (80% Escherichia coli; 20% Enterococcus faecium). Furthermore, the patients in group A had a higher number of GZB spot-forming colonies than the patients in group B (P < 0.001). GZB-positive cells were lower in the peripheral blood than those found in the AF of patients with SBP, while no differences were found between blood and AF in group B. Furthermore, after antibiotic treatment, GZB was reduced in the patients with SBP (P < 0.05). In conclusion, GZB may be an important mediator of the immune response towards bacteria in AF and could be used as a diagnostic tool. [source] Comorbidity and mixed anxiety-depressive disorder: clinical curiosity or pathophysiological need?HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue S1 2001Hans-Ulrich Wittchen Abstract The paper reviews available epidemiological evidence for the existence of and the implications of comorbidity of anxiety and depressive disorders and mixed anxiety,depressive (MAD) disorders. Using epidemiolological evidence of prevalence and incidence and data relating to time-course of illness, risk factor and outcome, it is concluded: (1) that anxiety,depression comorbidity is quite frequent in epidemiological and clinical settings throughout the world; (2) this comorbidity is diagnosis-specific and is associated with increased vulnerabilities and risks as well as poorer outcome and marked disabilities; and (3) no such evidence was found for MAD disorders. Contrary to what was predicted, the prevalence of MAD disorders was quite low even when using the more recent criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. (4) Furthermore, there was quite a heterogeneous pattern in terms of risk, severity and outcome making it questionable whether this disorder, as currently defined, is a clinical entity. These findings are discussed in terms of two perspectives, the ,lumpers' with their dimensional view and the ,splitters' with their categorical view. It is concluded that although comorbidity of threshold anxiety and depressive disorders seems to be an important phenomenon, no such evidence is provided for MAD disorders. Copyright © 2001 John Wiley & Sons, Ltd. [source] IL-18 gene promoter ,137C/G and ,607C/A polymorphisms in Chinese Han children with type 1 diabetes mellitusINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 2 2007G. P. Dong Summary Type 1 diabetes mellitus (T1DM) is a heterogeneous autoimmune disease, and both environmental and genetic factors play a role in its pathogenesis. Interleukin (IL)-18 is a potent pro-inflammatory cytokine capable of inducing interferon-gamma production that is associated with the development of T1DM. The gene for IL-18 is located on chromosome 11q22.2-q22.3 and has been reported to be associated with a susceptibility to T1DM. To test the putative involvement between IL-18 gene polymorphism and predisposition to T1DM, we conducted a case-control study in Chinese Han children. The single nucleotide polymorphisms at position ,607(C/A) and ,137(C/G) in the promoter region of the IL-18 gene were analysed by sequence-specific primers-polymerase chain reaction in 118 patients with T1DM and 150 healthy controls. (1) The allele frequency of ,607A was 41.2% and 53.0%, respectively, in patients and in control subjects (P = 0.01), but the allele frequency of ,137C/G was not statistically significant (P = 0.37). (2) The distribution of CC genotype at position ,607 was significantly different between patients and normal controls (P = 0.03), while the distribution of AA genotype in patients was significantly lower than that in the controls (P = 0.03). (3) Furthermore, there was a significant increase in haplotype (,137C/,607G) and genotype combination (,137GG/ ,607CC) in patients compared with controls (P = 0.03 and P = 0.04, respectively). The results of this study show that IL-18 gene promoter polymorphisms confer susceptibility to T1DM in Chinese Han children. Moreover, subjects carrying AA genotype at position ,607 of the promoter of IL-18 gene may be a low risk of T1DM development. [source] Colon cancer cell adhesion in response to Src kinase activation and actin-cytoskeleton by non-laminar shear stress,JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2004Vijayalakshmi Thamilselvan Abstract Malignant cells shed from tumors during surgical resection or spontaneous metastasis experience physical forces such as shear stress and turbulence within the peritoneal cavity during irrigation, laparoscopic air insufflation, or surgical manipulation, and within the venous or lymphatic system. Since physical forces can activate intracellular signals that modulate the biology of various cell types in vitro, we hypothesized that shear stress and turbulence might increase colon cancer cell adhesion to extracellular matrix, potentiating metastatic implantation. Primary human malignant colon cancer cells isolated from resected tumors and SW620 were subjected to shear stress and turbulence by stirring cells in suspension at 600 rpm for 10 min. Shear stress for 10 min increased subsequent SW620 colon cancer cell adhesion by 40.0,±,3.0% (n,=,3; P,<,0.001) and primary cancer cells by 41.0,±,3.0% to collagen I when compared to control cells. In vitro kinase assay (1.5,±,0.13 fold) and Western analysis (1.34,±,0.04 fold) demonstrated a significant increase in Src kinase activity in cells exposed shear stress. Src kinase inhibitors PP1 (0.1 µM), PP2 (20 µM), and actin-cytoskeleton stabilizer phalloidin (10 µM) prevented the shear stress stimulated cell adhesion to collagen I. Furthermore, PP2 inhibited basal (50.0,±,2.8%) and prevented shear stress induced src activation but phalloidin pretreatment did not. These results raise the possibility that shear stress and turbulence may stimulate the adhesion of malignant cells shed from colon cancers by a mechanism that requires both actin-cytoskeletal reorganization an independent physical force activation of Src kinase. Blocking this pathway might reduce tumor metastasis during surgical resection. Published 2004 Wiley-Liss, Inc. [source] Strategies to model the near-solute solvent molecular density/polarizationJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 5 2009Pei-Kun Yang Abstract The solvent molecular distribution significantly affects the behavior of the solute molecules and is thus important in studying many biological phenomena. It can be described by the solvent molecular density distribution, g, and the solvent electric dipole distribution, p. The g and p can be computed directly by counting the number of solvent molecules/dipoles in a microscopic volume centered at r during a simulation or indirectly from the mean force F and electrostatic field E acting on the solvent molecule at r, respectively. However, it is not clear how the g and p derived from simulations depend on the solvent molecular center or the solute charge and if the gF and pE computed from the mean force and electric field acting on the solvent molecule, respectively, could reproduce the corresponding g and p obtained by direct counting. Hence, we have computed g,p,gF, and pE using different water centers from simulations of a solute atom of varying charge solvated in TIP3P water. The results show that gF and pE can reproduce the g and p obtained using a given count center. This implies that rather than solving the coordinates of each water molecule by MD simulations, the distribution of water molecules could be indirectly obtained from analytical formulas for the mean force F and electrostatic field E acting on the solvent molecule at r. Furthermore, the dependence of the g and p distributions on the solute charge revealed provides an estimate of the change in g and p surrounding a biomolecule upon a change in its conformation. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009 [source] Two New Statistics to Detect Answer CopyingJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 1 2003Leonardo S. Sotaridona Two new indices to detect answer copying on a multiple-choice test,S1 and S2,were proposed. The S1 index is similar to the K index (Holland, 1996) and the K2 index (Sotaridona & Meijer, 2002) but the distribution of the number of matching incorrect answers of the source and the copier is modeled by the Poisson distribution instead of the binomial distribution to improve the detection rate of K and K2. The S2 index was proposed to overcome a limitation of the K and K2 index, namely, their insensitiveness to correct answers copying. The S2 index incorporates the matching correct answers in addition to the matching incorrect answers. A simulation study was conducted to investigate the usefulness of S1 and S2 for 40- and 80-item tests, 100 and 500 sample sizes, and 10%, 20%, 30%, and 40% answer copying. The Type I errors and detection rates of S1 and S2 were compared with those of the K2 and the , copying index (Wollack, 1997). Results showed that all four indices were able to maintain their Type I errors, with S1 and K2 being slightly conservative compared to S2 and ,. Furthermore, S1 had higher detection rates than K2. The S2 index showed a significant improvement in detection rate compared to K and K2. [source] TOOTH WHITENING IN CHILDREN AND ADOLESCENTSJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 6 2005Kevin J. Donly DDS The popularity of vital tooth whitening has increased significantly over the past two decades. Professionally supervised "in-office" and "at-home" tooth whitening methods have been documented in the literature with evidence of safety and effectiveness. Although the literature includes considerable information about vital tooth whitening in adults, minimal information is available concerning vital tooth whitening in children and adolescents. The need to provide vital tooth whitening for children might be infrequent owing to the natural whiteness of children's teeth. However, there are circumstances when tooth whitening can be desirable for children, such as fluorosis discoloration, generalized tooth darkening, post-traumatic injury discoloration, and postorthodontic tooth discoloration. Few well-controlled clinical trials evaluating the safety and effectiveness of vital tooth whitening in children are available in the literature, Furthermore, these published clinical trials were carried out by the same principal investigator. This review examines these trials and offers recommendations accordingly. [source] PROTECTIVE EFFECT OF LYSOSTAPHIN FROM STAPHYLOCOCCUS SIMULANS AGAINST GROWTH OF STAPHYLOCOCCUS AUREUS IN MILK AND SOME OTHER FOOD PRODUCTSJOURNAL OF FOOD SAFETY, Issue 3 2007PIOTR SZWEDA ABSTRACT The effect of lysostaphin from Staphylococcus simulans expressed in Escherichia coli TOP10 strain on Staphylococcus aureus used for inoculation of milk, ground pork and mayonnaise salad was investigated. The populations of this pathogen in ultrahigh-temperature milk preserved at 4C by lysostaphin added up to concentrations of 1.5 or 3.0 µg/mL were reduced by 0.73 and 0.92 log(cfu/mL) in control samples without enzyme addition. The protective influence of lysostaphin was diminished in case of milk storage (20C) prolonged up to 24 h. Furthermore, a final reduction level by 0.92 log(cfu/mL) was achieved after 24 h of pork storage. The smaller and more dependent on enzyme concentration inactivation of S. aureus was observed in the case of the mayonnaise salad, and it led to the conclusion that some food components or proteolytic enzymes originating from other bacteria caused lysostaphin inactivation. [source] Characteristics of Sarcoplasmic Proteins and Their Interaction with Surimi and Kamaboko GelJOURNAL OF FOOD SCIENCE, Issue 1 2009A. Jafarpour ABSTRACT:, This study examined the effect of adding common carp sarcoplasmic proteins (Sp- P) on the gel characteristics of threadfin bream surimi and kamaboko while maintaining constant moisture and myofibrillar levels. Based on the temperature sweep test, which is involved in heating of surimi gel from 10 to 80 °C to monitor the viscoelastic properties, at temperature range of 40 to 50 °C, the decrease level (depth of valley) in storage modulus (G,) thermograph was in proportion to the concentration of added Sp- P. Storage modulus (G,) showed greater elasticity after adding Sp- P compared with the control without Sp- P. Furthermore, the breaking force and distance and consequently gel strength of the resultant kamaboko were improved significantly (P > 0.05). Thus, added Sp- P did not interfere with myofibrillar proteins during sol,gel transition phase but associated with textural quality enhancement of resultant kamaboko; however, addition of Sp- P from the dark muscle of the carp decreased the whiteness of the resultant surimi. Furthermore, according to the SEM micrographs, the gel strength could not be associated with either the number of polygonal structures/mm2 or the area of the polygonal structures in the kamaboko gel microstructure. [source] Antioxidant and Antimutagenic Activity of Dietary Chlorophyll Derivatives Determined by Radical Scavenging and Bacterial Reverse Mutagenesis AssaysJOURNAL OF FOOD SCIENCE, Issue 7 2002M.G. Ferruzzi ABSTRACT: In vitro antioxidant and antimutagenic activity of dietary chlorophyll derivatives was assessed. Antioxidant activity was determined by the ability of each compound to scavenge the long-lived free radicals 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2,-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS+). Antimutagenic activity was assayed with a modified microscreen bacterial reverse mutagenicity assay using Salmonella typhimurium TA100 and benzo[a]pyrene as the tester strain and mutagen respectively. Derivatives of chlorophyll a were found to be more effective radical quenchers than those of chlorophyll b. Furthermore, metal-free derivatives such as chlorins, pheophytins, and pyropheophytins exhibited significantly lower antiradical capacity than metallo-derivatives such as Mg-chlorophylls, Zn-pheophytins, Zn-pyropheophytins, Cu-pheophytina, andCu-chlorophyllins. Both metal-free and metallo-chlorophyll derivatives demonstrated similar dose-dependent inhibitory activity against B[a]P induced mutagenesis. These results demonstrate that dietary chlorophyll derivatives prevalent in both fresh and processed foods and dietary supplements have antioxidant and antimutagenic activities. [source] On Vertices of outdegree n in minimally n -connected digraphsJOURNAL OF GRAPH THEORY, Issue 2 2002W. Mader Abstract Let |D| and |D|+n denote the number of vertices of D and the number of vertices of outdegree n in the digraph D, respectively. It is proved that every minimally n -connected, finite digraph D has |D|+n,,,n,+,1 and that for n,,,2, there is a cn,>,0 such that for all minimally n -connected, finite digraphs D. Furthermore, case n,=,2 of the following conjecture is settled which says that every minimally n -connected, finite digraph has a vertex of indegree and outdegree equal to n. © 2002 John Wiley & Sons, Inc. J Graph Theory 39: 129,144, 2002 [source] Antioxidants, vitamin C and dithiothreitol, activate membrane-bound guanylate cyclase in PC12 cellsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2001Zi-Jiang Chen Antioxidants and antioxidant enzymes are known to protect against cell death induced by reactive oxygen species. However, apart from directly quenching free radicals, little is known about the effect of antioxidants on hormone-activated second messenger systems. We previously found that antioxidants such as 17-, estradiol and resveratrol activate membrane-bound guanylate cyclase GC-A, the receptor for atrial natriuretic factor (ANF), in PC12 cells. It is possible that other antioxidants may also activate membrane-bound guanylate cyclase GC-A. The aim of this study was to determine if dithiothreitol (DTT), vitamin C, and vitamin E activate membrane-bound guanylate cyclase GC-A in PC12 cells. The results showed that both DTT and vitamin C increased cGMP levels in PC12 cells, whereas vitamin E had no effect. DTT and vitamin C inhibited membrane-bound guanylate cyclase activity stimulated by ANF in PC12 cells. In contrast, DTT and vitamin C had no effect on soluble guanylate cyclase activity stimulated by substance P. Furthermore, NO synthase inhibitors L-NAME and aminoguanidine did not affect DTT- and vitamin C-stimulated guanylate cyclase activity. The results indicate that DTT and vitamin C, but not vitamin E, activate membrane-bound guanylate cyclase GC-A in PC12 cells. [source] Cathodic electrochemiluminescence of acetonitrile, acetonitrile,1,10-phenanthroline and acetonitrile,ternary Eu(III) complexes at a gold electrodeLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 2 2006Hong-Xiao Yu Abstract Cathodic electrochemiluminescence (ECL) behaviours of the acetonitrile, acetonitrile,1,10-phenanthroline (phen) and acetonitrile,ternary Eu(III) complex systems at a gold electrode were studied. One very weak cathodic ECL-2 at ,3.5 V was observed in 0.1 mol/L tetrabutylammonium tetrafluoroborate (TBABF4) acetonitrile solution. When 10 mmol/L tetrabutylammonium peroxydisulphate [(TBA)2S2O8] was added to 0.1 mol/L TBABF4 acetonitrile solution, another cathodic ECL-1 at ,2.7 V appeared and the potential for ECL-2 was shifted from ,3.5 to ,3.1 V. Furthermore, ECL-2 intensity was enhanced about 20-fold. When 1 × 10,4 mol/L phen was added to 0.1 mol/L TBABF4 + 10 mmol/L (TBA)2S2O8 acetonitrile solution, the ECL intensities of ECL-1 and ECL-2 were enhanced about 20-fold compared with those of 0.1 mol/L TBABF4 + 10 mmol/L (TBA)2S2O8 acetonitrile solution. The maximum emission peaks of ECL-1 and ECL-2 in the three systems mentioned above appeared at about 530 nm. The products obtained by electrolysing 0.1 mol/L TBABF4 acetonitrile solution at ,3.5 V for 20 min were analysed by Fourier Transform Infrared (FTIR) spectra and gas chromatography,mass spectrometry (GC,MS) and the emitter of ECL-1 and ECL-2 was identified as excited state polyacetonitrile. When ternary Eu(III) complexes were presented in 0.1 mol/L TBABF4 + 10 mmol/L (TBA)2S2O8 acetonitrile solution, another maximum emission peak with a narrow band centred at about 610 nm appeared in ECL-1 in addition to the maximum emission peaks at about 530 nm for ECL-1 and ECL-2. The emitter of ECL emission at 610 nm was identified as the excited states Eu(III)*. The mechanisms for cathodic ECL behaviours of the acetonitrile, acetonitrile,phen and acetonitrile,ternary Eu(III) complex systems at a gold electrode have been proposed. The extremely sharp emission bands for ternary Eu(III) complexes may have analytical potential. Copyright © 2006 John Wiley & Sons, Ltd. [source] Asymptotic convergence of p -Laplace equationswith constraint as p tends to 1MATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 9 2002Ken Shirakawa In this paper we treat the Euler,Lagrange equation of a functional including the p -Laplacian for 1 The Peritoneal Microcirculation in Peritoneal DialysisMICROCIRCULATION, Issue 5 2001BENGT RIPPE ABSTRACT This paper deals with the peritoneal microcirculation and with peritoneal exchange occurring in peritoneal dialysis (PD). The capillary wall is a major barrier to solute and water exchange across the peritoneal membrane. There is a bimodal size-selectivity of solute transport between blood and the peritoneal cavity, through pores of radius ,40,50 Å as well as through a very low number of large pores of radius ,250 Å. Furthermore, during glucose-induced osmosis during PD, nearly 40% of the total osmotic water flow occurs through molecular water channels, termed "aquaporin-1." This causes an inequality between 1,, and the sieving coefficient for small solutes, which is a key feature of the "threepore model" of peritoneal transport. The peritoneal interstitium, coupled in series with the capillary walls, markedly modifies small-solute transport and makes large-solute transport asymmetric. Thus, although severely restricted in the blood-to-peritoneal direction, the absorption of large solutes from the peritoneal cavity occurs at a high clearance rate (,1 mL/min), largely independent of molecular radius. True absorption of macromolecules to the blood via lymphatics, however, seems to be occurring at a rate of ,0.2 mL/min. Several controversial issues regarding transcapillary and transperitoneal exchange mechanisms are discussed in this paper. [source] The Rcs phosphorelay system is essential for pathogenicity in Erwinia amylovoraMOLECULAR PLANT PATHOLOGY, Issue 2 2009DONGPING WANG SUMMARY The Rcs phosphorelay system is a modified two-component signal transduction system found exclusively in Enterobacteriaceae. In this study, we characterized the roles of the Rcs system in Erwinia amylovora, a highly virulent and necrogenic enterobacterium causing fire blight disease on rosaceous plants. Our results showed that rcsB, rcsC, rcsD and rcsBD mutants were non-pathogenic on immature pear fruit. The bacterial growth of these mutants was also greatly reduced compared with that of the wild-type strain in immature pear fruit. In an in vitro amylovoran assay, rcsB and rcsD mutants were deficient in amylovoran production, whereas the rcsC mutant exhibited higher amylovoran production than that of the wild-type. Consistent with amylovoran production, expression of the amylovoran biosynthetic gene amsG, using green fluorescent protein as a reporter, was not detectable in rcsB, rcsD and rcsBD mutants both in vitro and in vivo. The expression of amsG in vitro was higher in the rcsC mutant than in the wild-type, whereas its expression in vivo was higher in the wild-type than in the rcsC mutant. In addition, rcs mutants were more susceptible to polymyxin B treatment than the wild-type, suggesting that the Rcs system conferred some level of resistance to polymyxin B. Furthermore, rcs mutants showed irregular and slightly reduced motility on swarming plates. Together, these results indicate that the Rcs system plays a major role in virulence and survival of E. amylovora in immature pear fruit. [source] Multigraph augmentation under biconnectivity and general edge-connectivity requirements ,NETWORKS: AN INTERNATIONAL JOURNAL, Issue 3 2001Toshimasa Ishii Abstract Given an undirected multigraph G = (V, E) and a requirement function r,: () , Z+ (where () is the set of all pairs of vertices and Z+ is the set of nonnegative integers), we consider the problem of augmenting G by the smallest number of new edges so that the local edge-connectivity and vertex-connectivity between every pair x, y , V become at least r,(x, y) and two, respectively. In this paper, we show that the problem can be solved in O(n3(m + n) log(n2/(m + n))) time, where n and m are the numbers of vertices and pairs of adjacent vertices in G, respectively. This time complexity can be improved to O((nm + n2 log n) log n), in the case of the uniform requirement r,(x, y)= ,, for all x, y , V. Furthermore, for the general r,, we show that the augmentation problem that preserves the simplicity of the resulting graph can be solved in polynomial time for any fixed ,,* = max{r,(x, y) | x, y , V}. © 2001 John Wiley & Sons, Inc. [source] Renal carcinogenesis induced by ferric nitrilotriacetate in mice, and protection from it by Brazilian propolis and Artepillin CPATHOLOGY INTERNATIONAL, Issue 9 2000Tetsuo Kimoto The protective effect of Brazilian propolis and its extract Artepillin C against ferric nitrilotriacetate (Fe-NTA)-induced renal lipid peroxidation and carcinogenesis was studied in male ddY mice. Fe-NTA-induced renal lipid peroxidation leads to a high incidence of renal cell carcinoma (RCC) in mice. Administration of propolis by gastric intubation 2 h before or Artepillin C at either the same time, 2 h, or 5 h before the intraperitoneal injection of Fe-NTA (7 mg Fe/kg) effectively inhibited renal lipid peroxidation. This was evaluated from the measurement of renal thiobarbituric acid-reactive substances (TBARS) or histochemical findings of 4-hydroxy-2-nonenal (4-HNE)-modified proteins and 8-hydroxy-2, -deoxyguanosine (8-OHdG). Repeated injection of Fe-NTA (10 mg Fe/kg per day, twice a week for a total of 16 times in 8 weeks) caused subacute nephrotoxicity as revealed by necrosis and pleomorphic large nuclear cells in the renal proximal tubules, and gave rise to RCC 12 months later. A protective effect from carcinogenicity was observed in mice given propolis or Artepillin C. Furthermore, the mice given Fe-NTA only developed multiple cysts composed of precancerous lesions with multilayered and proliferating large atypical cells. Mice treated with propolis and Artepillin C also had cysts, but these were dilated and composed of flat cells. These results suggest that propolis and Artepillin C prevent oxidative renal damage and the carcinogenesis induced by Fe-NTA in mice. [source] Metternich, Bismarck, and the Myth of the "Long Peace," 1815,1914PEACE & CHANGE, Issue 3 2007Sheldon Anderson Many Western scholars and foreign-policy makers have lauded the Congress of Vienna, Metternich's "Concert of Europe," and Prussian chancellor Otto von Bismarck's alliance system for keeping a "long peace" from 1815 to 1914. The superiority of nineteenth-century statecraft is a myth. Europe was busy at war between 1815 and 1914, if not in conflicts on the scale of the Napoleonic Wars and World War I. Furthermore, the chancelleries of nineteenth-century Europe not only quelled national uprisings, but suppressed peoples' political rights and waged imperial wars throughout Africa and Asia. From the perspective of a Pole, a disenfranchised European, or an Indian, the century was not a "long peace" but a "long war." [source] Influence of piezoelectric fields on excitonic complexes in InGaN quantum dotsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 4 2009K. Sebald Abstract We present an analysis of the optical properties of single InGaN quantum dots (QDs) grown by MOVPE. The samples were structured into mesas by focused-ion-beam etching and investigated by micro-photoluminescence measurements. The QDs are characterized by the high temperature stability of their emission up to 150 K. Furthermore, the polarization of individual QD emission lines was analyzed giving an insight into their geometrical shape. Time-resolved microphotoluminescence measurements on the excitonic and biexcitonic transition of a single quantum dot yields a radiative recombination lifetime of 2.06 ns for the exciton. The data can be fitted by a simple model for cascaded emission confirming the expected refilling of the excitonic state by biexcitonic recombination. In addition, the influence of piezoelectric fields on the exciton and biexciton emission and on their binding energy in single QDs was investigated. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Analysis of minority carrier lifetime for InAlAs/InGaAs high electron mobility transistors by using 1.55-,m femto-second pulse laserPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 9 2008Hirohisa Taguchi Abstract The minority carrier lifetime (,) of High electron mobility transistors (HEMTs) made using the InAlAs/InGaAs material system lattice-matched to the InP substrate had been obtained from optical response measurements with a 1.55-,m femto-second pulse laser where the laser was illuminated onto the backside of a wafer. The drain current of HEMTs associated with the optical pulse was detected using a digitizing oscilloscope, and , was estimated from the exponential dependence of drain current on time. In our current investigation, we found that , is dominated by the following modes: (1) the amount of time required for holes to transit across the channel toward the source, and (2) the amount of time required for the holes accumulated in the source region to recombine with two-dimensional electron gas (2DEG) through the Auger mechanism. Because the sheet concentration (ps) of holes accumulated in source region is low at a low source-to-drain voltage (VDS), Auger recombination is not predominant, and , was only dominated by the hole transit time. At a high VDS, ps became high enough for Auger recombination to occur and dominate ,. Furthermore, we investigated the optical power dependence of , where the optical power was supplied in a continuous wave (CW) to generate photo-excited holes in a steady state. The value of , decreased monotonically as VDS increased and saturated in as little as 6x10,10 s when the optical power was increased. The theoretical investigation was made to understand this saturation phenomenon. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Uncoupling brassinosteroid levels and de-etiolation in peaPHYSIOLOGIA PLANTARUM, Issue 2 2002Gregory M. Symons The suggestion that brassinosteroids (BRs) have a negative regulatory role in de-etiolation is based largely on correlative evidence, which includes the de-etiolated phenotypes of, and increased expression of light-regulated genes in, dark-grown mutants defective in BR biosynthesis or response. However, we have obtained the first direct evidence which shows that endogenous BR levels in light-grown pea seedlings are increased, not decreased, in comparison with those grown in the dark. Similarly, we found no evidence of a decrease in castasterone (CS) levels in seedlings that were transferred from the dark to the light for 24 h. Furthermore, CS levels in the constitutively de-etiolated lip1 mutant are similar to those in wild-type plants, and are not reduced as is the case in the BR-deficient lkb plants. Unlike lip1, the pea BR-deficient mutants lk and lkb are not de-etiolated at the morphological or molecular level, as they exhibit neither a de-etiolated phenotype or altered expression of light-regulated genes when grown in the dark. Similarly, dark-grown WT plants treated with the BR biosynthesis inhibitor, Brz, do not exhibit a de-etiolated phenotype. In addition, analysis of the lip1lkb double mutant revealed an additive phenotype indicative of the two genes acting in independent pathways. Together these results strongly suggest that BR levels do not play a negative-regulatory role in de-etiolation in pea. [source] Epoxy nanocomposites curing by microwavesPOLYMER ENGINEERING & SCIENCE, Issue 8 2006Nurseli Uyan In this work, chemically modified sodium montmorillonite and epoxy monomer were used to prepare nanocomposites in two consecutive stages. In the first stage, dodecylamine, octadecylamine, hexadecylamine, and hexadecyltrimethyl ammonium bromide were used to prepare various organophilic clays. In the second stage, the bisphenol-A based epoxy monomer and predetermined amounts of organoclay were mixed together and then cured by an aliphatic polyamine for 20 min under microwave at 400 W. Furthermore, ,-, diacrylate poly(dimethylsiloxane) was added to the mixture before the curing process to modify the toughness of the samples. The mixture was poured into the poly(tetrafluoroethylene) mold; the epoxy resin/curing agent ratio was maintained as 2/1. The clear films formed after microwave irradiation were removed from the mold, cooled, and then stored in a cool and dry medium until characterization. The samples were analyzed by wide angle X-ray diffraction, differential scanning calorimetry, and mechanical tests. Surfaces of the cold fractured samples were also observed under the scanning electron microscope. The results revealed that microwave curing of the samples of 5% organoclay and 5% siloxane showed improvement in mechanical properties. POLYM. ENG. SCI. 46:1104,1110, 2006. © 2006 Society of Plastics Engineers [source] Experimental annotation of channel catfish virus by probabilistic proteogenomic mappingPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 10 2009Dusan Kunec Dr. Abstract Experimental identification of expressed proteins by proteomics constitutes the most reliable approach to identify genomic location and structure of protein-coding genes and substantially complements computational genome annotation. Channel catfish herpesvirus (CCV) is a simple comparative model for understanding herpesvirus biology and the evolution of the Herpesviridae. The canonical CCV genome has 76 predicted ORF and only 12 of these have been confirmed experimentally. We describe a modification of a statistical method, which assigns significance measures, q -values, to peptide identifications based on 2-D LC ESI MS/MS, real-decoy database searches and SEQUEST XCorr and ,Cn scores. We used this approach to identify CCV proteins expressed during its replication in cell culture, to determine protein composition of mature virions and, consequently, to refine the canonical CCV genome annotation. To complement trypsin, we used partial proteinase K digestion, which yielded greater proteome coverage. At FDR <5%, for peptide identifications, we identified 25/76 previously predicted ORF using trypsin and 31/76 using proteinase K. Furthermore, we identified 17 novel protein-coding regions (7 potential ATG-initiated ORF). Most of these novel ORF encode small proteins (<100 amino acids). Directed, strand-specific reverse transcription real-time PCR confirmed RNA expression from 6/7 novel ATG-initiated ORF investigated. [source] Reverse micellar microextraction for rapid analysis of thiol-containing peptides and amino acids by atmospheric-pressure matrix-assisted laser desorption/ionization ion trap and matrix-assisted laser desorption/ionization time-of-flight mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 9 2008Kavita Agrawal Simple, rapid and inexpensive one-step reverse micellar microextraction (RMME) procedures were combined with matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) for the determination of thiol-containing peptides and amino acids. In this investigation, a thiol-containing peptide (HW6) was chosen as model compound to understand the mechanism of RMME. The electrostatic interactions between the thiol-containing peptide and reverse micelles were proposed to be reason for the transfer of analytes from the aqueous phase to the organic phase. Reverse micelles were formed by the cationic surfactant, methyltrioctylammonium chloride (MTOAC). The best extraction efficiency of HW6 was obtained under the following conditions: pH 11.0, ionic strength 5.0,mM of KCl and micelle concentration 7.0,mM of MTOAC. The limits of detection (LODs) obtained for HW6 in water, urine and plasma samples were 0.15, 0.19 and 0.28,µM, respectively, with relative standard deviation (RSD) values in the range ±8.8,10.5%. The sensitivity obtained in water by the present method was 45-fold higher than that of the conventional use of atmospheric-pressure (AP)-MALDI MS. Furthermore, the applicability of the proposed approach was extended for the determination of thiol-containing amino acids in sample solutions by using MALDI time-of-flight (TOF) MS. Copyright © 2008 John Wiley & Sons, Ltd. [source]
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