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Interplay
Kinds of Interplay Selected AbstractsINTERPLAY OF REACTIVE OXYGEN SPECIES AND NITRIC OXIDE IN THE PATHOGENESIS OF EXPERIMENTAL LEAD-INDUCED HYPERTENSIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2007ND Vaziri SUMMARY 1Lead is a common environmental and industrial toxin that can cause a variety of acute and chronic illnesses. For example, chronic exposure to low levels of lead has been shown to raise arterial pressure and promote renal and cardiovascular complications. 2Several mechanisms have been identified by which chronic lead exposure can cause hypertension and cardiovascular disease. In recent years, increasing evidence has emerged pointing to the role of oxidative stress as a major mediator of lead-induced hypertension. 3The present article provides an overview of the published studies on this subject. [source] Reversal of End-Stage Heart Failure: Mechanical and Pharmacologic InterplayCONGESTIVE HEART FAILURE, Issue 1 2007Imran S. Virk MD No abstract is available for this article. [source] Interplay of constitutively released nucleotides, nucleotide metabolism, and activity of P2Y receptorsDRUG DEVELOPMENT RESEARCH, Issue 2-3 2001Eduardo R. Lazarowski Abstract At least six mammalian P2Y receptors exist that are specifically activated by ATP, UTP, ADP or UDP. Although the existence of ectoenzymes that rapidly metabolize extracellular nucleotides is well established, the relative flux of ATP and UTP through their extracellular metabolic products remains undefined. In addition, the existence of basal nucleotide release and the contribution of resting levels of ATP and UTP to P2 receptor activation are poorly understood. In the absence of exogenous agonists, an apyrase-sensitive inositol phosphate accumulation was observed in resting 16HBE14o, human bronchial epithelial cells endogenously expressing P2Y receptors and in 1321N1 human astrocytoma cells expressing a recombinant P2Y2 receptor. To test whether nucleotide release may account for basal P2 receptor activities, the rates of extracellular accumulation and metabolism of endogenous ATP were examined with resting 16HBE14o,, C6 rat glioma, and 1321N1 cell cultures. Although extracellular ATP concentrations (1-5 nM) remained unchanged for up to 12 h, [,32P] ATP included in the medium (as a radiotracer) was completely degraded within 120 min, indicating that ATP release balanced ATP hydrolysis. The calculated basal rates of ATP release ranged from 20 to 200 fmol/min per million cells. HPLC analysis during steady state revealed that the gamma-phosphate of ATP was reversibly transferred to species further identified as UTP and GTP, implicating ecto-nucleoside diphosphokinase (NDPK)-catalyzed phosphorylation of endogenous UDP and GDP. At steady state, the final 32P-products of [,32P]ATP metabolism were 32P-orthophosphoric acid and a species further purified and identified as 32P-pyrophosphate. Constitutive nucleotide release balanced by the concerted activities of ecto-ATPase, ecto-ATP pyrophosphatase, and ecto-NDPK may determine the resting levels of extracellular nucleotides and therefore, the basal activity of P2 receptors. Drug Dev. Res. 53:66,71, 2001. © 2001 Wiley-Liss, Inc. [source] Interplay of genetic risk factors and parent monitoring in risk for nicotine dependenceADDICTION, Issue 10 2009Li-Shiun Chen ABSTRACT Background Several studies have found replicable associations between nicotine dependence and specific variants in the nicotinic receptor genes CHRNA5(rs16969968) and CHRNA3(rs3743078). How these newly identified genetic risks combine with known environmental risks is unknown. This study examined whether the level of parent monitoring during early adolescence modified the risk of nicotine dependence associated with these genetic variants. Methods In a cross-sectional case,control study of US-based community sample of 2027 subjects, we use a systematic series of regression models to examine the effect of parent monitoring on risk associated with two distinct variants in the nicotinic receptor genes CHRNA5(rs16969968) and CHRNA3(rs3743078). Results Low parent monitoring as well as the previously identified genetic variants were associated with an increased risk of nicotine dependence. An interaction was found between the SNP(rs16969968) and parent monitoring (P = 0.034). The risk for nicotine dependence increased significantly with the risk genotype of SNP(rs16969968) when combined with lowest-quartile parent monitoring. In contrast, there was no evidence of an interaction between SNP(rs3743078) and parent monitoring (P = 0.80). Conclusions The genetic risk of nicotine dependence associated with rs16969968 was modified by level of parent monitoring, while the genetic risk associated with rs3743078 was not, suggesting that the increased risk due to some genes may be mitigated by environmental factors such as parent monitoring. [source] Interplay of actors, scales, frameworks and regimes in the governance of biodiversityENVIRONMENTAL POLICY AND GOVERNANCE, Issue 3 2009Jouni Paavola Abstract This article examines the key contributions of the political science and systems theory based literatures on environmental governance, and uses them to analyse the governance of biodiversity in Europe. The article suggests that the key insights of the two bodies of literature are a distinction between governance frameworks and regimes on one hand, and the importance of multifaceted and multiple scales on the other. These key insights draw attention to horizontal and vertical forms of interplay. The article suggests that interplay, both between actors and levels and between frameworks and regimes, is ubiquitous and ambivalent: it can either foster or hinder environmental governance. The article illustrates this discussion in the context of governance of biodiversity in Europe, highlighting how vertical and horizontal interplay between the governance framework for biodiversity and the broader institutional setting or regime have characterized the implementation of the Habitats Directive, both complicating and fostering the governance of biodiversity in Europe. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment. [source] Deslipping of Ester Rotaxanes: A Cooperative Interplay of Hydrogen Bonding with Rotational BarriersEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2003Petra Linnartz Abstract A series of rotaxanes has been synthesized which contain two ester groups in their axles. All rotaxanes bear the same tetralactam wheel. The kinetics of the de-slipping reaction of these rotaxanes were monitored in tetrachloroethane (TCE) and dimethyl sulfoxide (DMSO) resulting in the observation of a significant solvent effect. In TCE, two isomeric rotaxanes that differ merely with respect to the orientation of the ester groups show a remarkable difference in their deslipping behavior. When the ester carbonyl group is directly attached to the axle center piece, the rotaxane decomposes with a half life of ca. 10 h at 100 °C. The reverse orientation with the carbonyl group attached to the stopper blocks deslipping almost completely and a lower limit for the half life at 100 °C of 25,000 h was obtained. These results can be interpreted by inferring a cooperative action of hydrogen bonding between wheel and axle and differences in rotational barriers. Molecular modeling and AM1 calculations support this interpretation. The implications of these results for the determination of steric size and the optimization of molecular machines are discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Interplay of Properties and Functions upon Introduction of Mesoporosity in ITQ-4 ZeoliteADVANCED FUNCTIONAL MATERIALS, Issue 9 2010Danny Verboekend Abstract The introduction of mesoporosity in zeolites is often directly coupled to changes in their overall catalytic performance without the detailed assessment of other key functions required for the rational design of the catalytic process such as accessibility, adsorption, and transport. This study presents an integrated approach to study property,function relationships in hierarchical zeolites. Accordingly, desilication of the 1D ITQ-4 zeolite in alkaline medium is applied to develop different degrees of mesoporosity. Along with porosity modification, significant changes in composition, structure, and acidity occur. Relationships are established between the physicochemical properties of the zeolites and their characteristics in the adsorption and elution of light hydrocarbons (C2 to C5, alkanes and alkenes) as well as in the catalytic activity in low-density polyethylene (LDPE) pyrolysis. The recently introduced hierarchy factor can appropriately relate porosity changes to catalytic performance. [source] Interplay between global patterns of environmental temperature and variation in nonshivering thermogenesis of rodent species across large spatial scalesGLOBAL CHANGE BIOLOGY, Issue 9 2009ENRIQUE RODRÍGUEZ-SERRANO Abstract The purpose of this study was to test for correlations of mass-independent nonshivering thermogenesis (NST) in rodent species with climatic factors such as maximum and minimum geographic temperature. We first analyzed whether the responses of rodents show a phylogenetic signal. If so, and if the NST over a broad geographical range is similar, then such responses probably reflect physiological evolutionary adaptation. Our results show that NST did not show phylogenetic signal, appears to be evolutionary labile and is negatively correlated with environmental temperature. We predicted that species evolved in cold climates will exhibit higher mass-independent NST than species from warmer habitats. Indeed, we observed that the relationships between mass-independent NST and minimum temperature (rs=,0.411, P=0.009) as well as between NST and maximum temperature (rs=,0.443, P=0.004) were both negatively and significantly correlated, thus supporting our predictions. Thus, thermal physiology may be a significant factor underlying the ecological and evolutionary success of animals. Finally we suggest that due to the pressing need to explain and predict the likely biological impact of climatic change, advances in this field are necessary. [source] Multifunctional Nanocrystalline Thin Films of Er2O3: Interplay between Nucleation Kinetics and Film CharacteristicsADVANCED FUNCTIONAL MATERIALS, Issue 1 2008M. Losurdo No abstract is available for this article. [source] Interplay of hepatic and myeloid signal transducer and activator of transcription 3 in facilitating liver regeneration via tempering innate immunity,HEPATOLOGY, Issue 4 2010Hua Wang Liver regeneration triggered by two-thirds partial hepatectomy is accompanied by elevated hepatic levels of endotoxin, which contributes to the regenerative process, but liver inflammation and apoptosis remain paradoxically limited. Here, we show that signal transducer and activator of transcription 3 (STAT3), an important anti-inflammatory signal, is activated in myeloid cells after partial hepatectomy and its conditional deletion results in an enhanced inflammatory response. Surprisingly, this is accompanied by an improved rather than impaired regenerative response with increased hepatic STAT3 activation, which may contribute to the enhanced liver regeneration. Indeed, conditional deletion of STAT3 in both hepatocytes and myeloid cells results in elevated activation of STAT1 and apoptosis of hepatocytes, and a dramatic reduction in survival after partial hepatectomy, whereas additional global deletion of STAT1 protects against these effects. Conclusion: An interplay of myeloid and hepatic STAT3 signaling is essential to prevent liver failure during liver regeneration through tempering a strong innate inflammatory response mediated by STAT1 signaling. (HEPATOLOGY 2010.) [source] Interplay between T helper type 1 and type 2 cytokines and soluble major histocompatibility complex molecules: a paradigm in pregnancyIMMUNOLOGY, Issue 3 2002I. Athanassakis No abstract is available for this article. [source] The First General and Selective Palladium(II)-Catalyzed Alkoxycarbonylation of Arylboronates: Interplay among Benzoquinone-Ligated Palladium(0) Complex, Organoboron, and Alcohol SolventADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Yoshihiko Yamamoto Abstract Methoxycarbonylation of aryl- and alkenylboron compounds was performed using the palladium(II) acetate/triphenylphosphine [Pd(OAc)2/PPh3] catalyst with p -benzoquinone as a stoichiometric oxidant in methanol at ambient temperature to obtain the corresponding methyl esters in good yields. A wide variety of functional groups including various carbonyl functionalities, nitrile, nitro, sulfone, and unprotected pyrrole rings were tolerated in the methoxycarbonlation, while the use of higher alcohols except for tert -butanol afforded various p -chlorobenzoates in moderate to high yields. The catalytic alkoxycarbonylation proceeded without any acid or base additive, and an oxidative transmetalation step is proposed to explain the exceptional efficacy of this protocol. DFT and MP2 calculations support the proposed mechanism. [source] Structural Modeling of Car Use on the Way to the University in Different Settings: Interplay of Norms, Habits, Situational Restraints, and Perceived Behavioral Control,JOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 8 2009Christian A. Klöckner This manuscript presents the results of the application of an extended norm activation model to the explanation of car use on the way to the university with a sample of 430 students of 3 German universities. The proposed two-stage structural model is supported by the data. First, a norm activation process starting with awareness of consequences activates subjective and personal norms. Second, behavior is determined by car-use habits, perceived behavioral control (PBC), car access, and effort to use public transportation. The influence of personal norms on behavior is mediated by habits. Subgroup analyses of the second stage of the model show a high structural stability, but differences in the regression weights. [source] Interplay among enteric neurons, interstitial cells of Cajal, resident and not resident connective tissue cellsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 7 2009Maria-Simonetta Faussone-PellegriniArticle first published online: 16 JUN 200 [source] Interplay between anion-, and hydrogen bonding interactionsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 1 2009Daniel Escudero Abstract The interplay between two important noncovalent interactions involving aromatic rings is studied by means of high level ab initio calculations. They demonstrate that synergistic effects are present in complexes where anion-, and hydrogen bonding interactions coexist. These synergistic effects have been studied using the "atoms-in-molecules" theory and the Molecular Interaction Potential with polarization partition scheme. The present study examines how these two interactions mutually influence each other. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009 [source] Social Capital and the Interplay of Families and SchoolsJOURNAL OF MARRIAGE AND FAMILY, Issue 2 2004Robert Crosnoe Families and schools are two primary sources of social capital in the early life course. This study examines the degree to which these different contexts overlap to shape adolescent development. Multilevel modeling on nationally representative data (n = 11,927) revealed that emotionally distant relationships with parents were associated with declining academic achievement over 2 years of secondary schooling and that various aspects of the social environments of schools were associated with increasing academic achievement during this same period. Additionally, adolescents who had more social capital at home often benefited more from social capital at school. [source] Neuropeptide Y Cotransmission with Norepinephrine in the Sympathetic Nerve,Macrophage InterplayJOURNAL OF NEUROCHEMISTRY, Issue 6 2000Rainer H. Straub Abstract: The CNS modulates immune cells by direct synaptic-likecontacts in the brain and at peripheral sites, such as lymphoid organs. Tostudy the nerve-macrophage communication, a superfusion method was used toinvestigate cotransmission of neuropeptide Y (NPY) with norepinephrine (NE),with interleukin (IL)-6 secretion used as the macrophage read-out parameter.Spleen tissue slices spontaneously released NE, NPY, and IL-6 leading to asuperfusate concentration at 3-4 h of 1 nM, 10 pM, and 120pg/ml, respectively. Under these conditions, NPY dose-dependently inhibitedIL-6 secretion with a maximum effect at 10 -10M(p = 0.012) and 10 -9M (p < 0.001).Simultaneous addition of NPY at 10 -9M and the,-2-adrenergic agonist p -aminoclonidine further inhibited IL-6secretion (p < 0.05). However, simultaneous administration of NPYat 10 -9M and the ,-adrenergic agonist isoproterenolat 10 -6M or NE at 10 -6Msignificantly increased IL-6 secretion (p < 0.005). To objectifythese differential effects of NPY, electrical field stimulation of spleenslices was applied to release endogenous NPY and NE. Electrical fieldstimulation markedly reduced IL-6 secretion, which was attenuated by the NPYY1 receptor antagonist BIBP 3226 (10 -7M, p = 0.039;10 -8M, p = 0.035). This indicates that NPY increases theinhibitory effect of endogenous NE, which is mediated at low NE concentrationsvia ,-adrenoceptors. Blockade of ,-adrenoceptors attenuatedelectrically induced inhibition of IL-6 secretion (p < 0.001),which was dose-dependently abrogated by BIBP 3226. This indicates that underblockade of ,-adrenoceptors endogenous NPY supports the stimulatingeffect of endogenous NE via ,-adrenoceptors. These experimentsdemonstrate the ambiguity of NPY, which functions as a cotransmitter of NE inthe nerve-macrophage interplay. [source] Personality Reflected in a Coherent Idiosyncratic Interplay of Intra- and Interpersonal Self-Regulatory ProcessesJOURNAL OF PERSONALITY, Issue 6 2006Carolyn C. Morf ABSTRACT This article discusses a framework that conceptualizes personality in terms of a unique pattern of interacting intra- and interpersonal self-regulatory mechanisms employed in the service of constructing and maintaining a desired self. These personal goals motivate the individuals' self-construction efforts and give direction, organization, and coherence to the self-regulatory dynamics,both within the person and in the social world in which they play out. The framework is illustrated through research on construct validation of the narcissistic personality type and extended by brief applications to dependency and rejection sensitivity to show how it may help us understand the complex signatures that are the expressions of a personality type. It offers a guide for where to look for and how to organize the unique features and idiosyncratic dynamics of different self-construction types and to make sense of their otherwise often seemingly paradoxical expressions. In so doing, the framework speaks to basic goals of personality psychology by providing an approach for capturing trait-like individual differences while simultaneously shedding light on the psychological mechanism that underlies them. [source] Teaching: An Interplay of Aims, Constraints, Conflicts, and CompromisesMODERN LANGUAGE JOURNAL, Issue 3 2000Larbi Oukada is essentially a contentious interplay of curricular and instructional aims and a host of regressive constraints, 4 of which are discussed in the present article. They are: (a) the endless and fallible nature of fully understanding knowledge and of representing it in an ontologically congruous manner (epistemological constraint); (b) the problems inherent in mediating knowledge through language (semiotic constraint); (c) the tenuous validity of the psychological assumptions on which the presentation of knowledge is conducted in the classroom (learning constraint); and (d) the local and potentially regressive variables, such as instructional time, language aptitude, attitude, personality, and motivation (environmental constraint). The thrust of the present article is to show that these 4 constraints exert inevitable and pedagogically fruitful tension on classroom teaching. [source] Large-scale chromatin remodeling in germinal vesicle bovine oocytes: Interplay with gap junction functionality and developmental competenceMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 6 2007Valentina Lodde Abstract In mammals, oocyte acquires a series of competencies sequentially during folliculogenesis that play critical roles at fertilization and early stages of embryonic development. In mouse, chromatin in germinal vesicle (GV) undergoes dynamic changes during oocyte growth and its progressive condensation has been related to the achievement of developmental potential. Cumulus cells are essential for the acquisition of meiotic competence and play a role in chromatin remodeling during oocyte growth. This study is aimed to characterize the chromatin configuration of growing and fully grown bovine oocytes, the status of communications between oocyte and cumulus cells and oocyte developmental potential. Following nuclear staining, we identified four discrete stages of GV, characterized by an increase of chromatin condensation. GV0 stage represented 82% of growing oocytes and it was absent in fully grown oocytes. GV1, GV2, and GV3 represented, respectively, 24, 31, and 45% of fully grown oocytes. Our data indicated a moderate but significant increase in oocyte diameter between GV0 and GV3 stage. By dye coupling assay the 98% of GV0 oocytes showed fully open communications while the number of oocytes with functionally closed communications with cumulus cells was significantly higher in GV3 group than GV1 and GV2. However, GV0 oocytes were unable to progress through metaphase II while GV2 and GV3 showed the highest developmental capability. We conclude that in bovine, the progressive chromatin condensation is related to the sequential achievement of meiotic and embryonic developmental competencies during oocyte growth and differentiation. Moreover, gap-junction-mediated communications between oocyte and cumulus cells could be implicated in modulating the chromatin remodeling process. Mol. Reprod. Dev. 74: 740,749, 2007. © 2006 Wiley-Liss, Inc. [source] Interplay of magnetism and superconductivityPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 11 2006M. Akhavan Abstract After about two decades of intense research since the discovery of high-temperature superconductivity (HTSC) in cuprates, although many aspects of the physics and chemistry of these cuprate superconductors are now well understood, the underlying pairing mechanism remains elusive. Magnetism and superconductivity are usually thought as incompatible, but in number of special materials including HTSCs these two mutually excluding mechanisms are found to coexist. The presence in a system of superconductivity and magnetism, gives rise to a large number of interesting phenomenon. This article provides perspective on recent developments and their implications for our understanding of the interplay between magnetism and superconductivity in new materials. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Interplay of electron,phonon and Coulomb interaction in semiconductor quantum dotsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2006J. Förstner The cover picture of this issue of physica status solidi (c) has been taken from the article [1]. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Interplay of genes and early mother,child relationship in the development of self-regulation from toddler to preschool ageTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 11 2009Grazyna Kochanska Background:, A broad capacity for deliberate self-regulation plays a key role in emotion regulation. This longitudinal investigation from infancy to preschool age examines genotype by environment (G × E) interaction in the development of self-regulation, using molecular measures of children's genotypes and observed measures of the quality of early mother,child relationship, as reflected in attachment organization in infancy. Methods:, In 89 children, we assessed the polymorphism in the serotonin transporter gene (5-HTTLPR, ss/sl vs. ll allele status), security of attachment to mothers at 15 months in the Strange Situation, and children's ability for self-regulation at 25, 38, and 52 months, using behavioral batteries of tasks that called for deliberately suppressing a dominant response and performing instead a sub-dominant response. Results:, There was a robust G × E interaction between genetic risk and the quality of early relationship. Among children who carried a short 5-HTTLPR allele (ss/sl,), those who were insecurely attached developed poor regulatory capacities, but those who were securely attached developed as good regulatory capacities as children who were homozygotic for the long allele (ll,). There was no effect of security for ll homozygotes. Conclusions:, Those findings, consistent with diathesis-stress model, bridge research on self-regulation in typically developing children with research on non-human primates and research on psychopathology. They also indicate that a secure attachment relationship can serve as a protective factor in the presence of risk conferred by a genotype. [source] Interplay between dipolar, stacking and hydrogen-bond interactions in the crystal structures of unsymmetrically substituted esters, amides and nitriles of (R,R)- O,O,-dibenzoyltartaric acidACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2001Urszula Rychlewska The compounds analysed are the O,O,-dibenzoyl derivatives of (R,R)-tartaric acid, asymmetrically substituted by ester, amide and nitrile groups. Benzoylation does not introduce drastic changes to the molecular conformation. All investigated molecules adopt the planar T conformation of the four-carbon chain with noticeably smaller departures from the ideal conformation than observed in the nonbenzoylated analogs. Primary and secondary amides always orient the C=O bond antiperiplanar (a) with respect to the nearest C*,O bond, while methylester groups adjust their conformation to that adopted by the amide substituent situated at the other end of the molecule. Tertiary amides and carboxyl groups place their carbonyls at the same side as the nearest C*,O bond (the s form), but often deviations from coplanarity of the two bonds are significant and higher than those observed in the nonbenzoylated series. The results presented demonstrate the importance of dipole/dipole interactions between CO and ,C*H groups in stabilizing the molecular conformation, and between carbonyl groups in stabilizing crystal packing of the molecules that lack classical hydrogen-bond donor groups. An illustration is provided as to how a small change in mutual orientation of molecules arranged in a close-packed fashion causes a change in the character of intermolecular interactions from van der Waals to sandwich stacking between the benzoyloxy phenyls, and to dipolar between the benzoyloxy carbonyls. Hydrogen-bonded molecules tend to orient in a head-to-tail mode; the head-to-head arrangement being limited to cases in which terminal carbonyl groups are situated at one side of the molecule. The orientation of the benzoyloxy substituents with respect to the carbon main chain is such that the (O=)C,O,C,H bond system often deviates significantly from planarity. [source] Basement membrane laminin-5 is deposited in colorectal adenomas and carcinomas and serves as a ligand for ,3,1 integrinAPMIS, Issue 3 2000Jouni Lohi Interplay between laminin-5 (Ln-5) and its integrin (Int) receptors ,2,1, ,3,1 and ,6,4 has been implicated in the progression and invasion of carcinomas. In this study we found abundant immuno-reactivity for chains of Ln-5 (,3-,3-,2) and Ln-10 (,5-,1), as well as for type VII collagen, in basement membranes (BM) of colorectal adenomas. In carcinomas of all differentiation grades, Lns were seen in tumor BMs, whereas type VII collagen was almost absent. Ln-5 appeared to accumulate along the invading edges of carcinomas, while Ln-10 was mostly absent. Immunoreactivity for Ln ,1 chain, a component of Lns-1 and -3, was not seen in adenomas or carcinomas. Immunoreactivity for ,2, ,6, ,1 and ,4 Ints was found in all tumors and that for ,3 Int in all adenomas and most of the carcinomas, often in colocalization with Ln-5. Immunoblotting of carcinoma tissues showed that the ,2 chain of Ln-5 was present as typical Mr 105000 and 155000 isoforms. Immunoprecipitation experiments showed production of Ln-5 by cultured colon carcinoma cells. In quantitative cell adhesion experiments, function-blocking MAbs to ,3 and ,1 Int subunits, but not those to Int ,2 or ,6 subunits, significantly inhibited the adhesion of cells to Ln-5. Our results suggest that BM composition in colorectal adenomas reflects the properties of surface epithelial BM of colorectal mucosa. In invading carcinomas, trimeric Ln-5, produced by carcinoma cells, is a major BM component and the cells use the ,3,1 Int complex for adhesion to Ln-5. [source] Cooperative Coexistence: Effective Interplay of Two Broensted Acids in the Asymmetric Synthesis of Isoquinuclidines.CHEMINFORM, Issue 11 2007Magnus Rueping 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] Self-Assembly of Calix[6]arene,Diazapyrenium Pseudorotaxanes: Interplay of Molecular Recognition and Ion-Pairing EffectsCHEMISTRY - A EUROPEAN JOURNAL, Issue 11 2010Monica Semeraro Abstract The calix[6]arene wheel CX forms pseudorotaxane species with the diazapyrenium-based axle 1,2PF6 in CH2Cl2 solution. The macrocyclic component is a heteroditopic receptor, which can complex the electron-acceptor moiety of the axle inside its cavity and the counterions with the ureidic groups on the upper rim. The self-assembled supramolecular species is a complex structure, which involves three components,the wheel, the axle and its counterions,that can mutually interact and affect. The stoichiometry of the resulting supramolecular complex depends on the nature and concentration of the counterions. Namely, it is observed that in dilute solution and with low-coordinating anions the axle takes two wheels, whereas with highly coordinating anions or in concentrated solutions the complex has a 1:1 stoichiometry. [source] Disulfides, Imines, and Metal Coordination within a Single System: Interplay between Three Dynamic EquilibriaCHEMISTRY - A EUROPEAN JOURNAL, Issue 34 2007Rupam Abstract We report a system in which three distinct dynamic linkages, disulfide (SS), imine (CN), and coordinative (N,metal) bonds were shown to be capable of simultaneous reversible exchange. The "disulfide layer" of the system under study consists of two homo-disulfides, bis(4-aminophenyl) disulfide 1 and bis(4-methoxyphenyl) disulfide 2 that equilibrate in the presence of catalytic amount of triethylamine to favor the formation of a hetero-disulfide product, 4-aminophenyl-4,-methoxyphenyl disulfide 3. The addition of 2-formylpyridine and a metal salt strongly perturbed this 1+2,3 equilibrium through the formation of metal complexes incorporating disulfide 1 as a subcomponent. CuI perturbed the equilibrium by a factor of 3.3, and FeII by a factor of 179, in both cases in favor of the homo-disulfides. The disulfide equilibrium could be further modified, following metal-complex formation, by coordinative (transmetallation: substitution of FeII for CuI) or covalent (imine exchange: the substitution of one amine residue for another) exchange. Thus, although the three kinds of dynamic linkages were demonstrated to be mutually compatible, changes at one kind of linkage could be used to predictably perturb an equilibrium involving another. [source] The Effect of Counterion/Ligand Interplay on the Activity and Stereoselectivity of Palladium(II),Diimine Catalysts for CO/p -Methylstyrene CopolymerizationCHEMISTRY - A EUROPEAN JOURNAL, Issue 5 2007Barbara Binotti Dr. Abstract The catalytic activity and stereoselectivity of complexes [Pd(,1,,2 -C8H12OMe)(ArNC(R,)C(R,)NAr)]X in the copolymerization of CO and p -methylstyrene have been correlated with their interionic structure in solution and in the solid state, as determined by 19F,1H-HOESY NMR spectroscopy and X-ray diffraction studies, respectively. The highest productivity is obtained with unhindered diimine ligands bearing electron-donating substituents and with the least coordinating counterion. Copolymers with a microstructure ranging from atactic to predominantly isotactic are obtained. The degree of isotacticity increases as the steric hindrance in the apical positions and the coordinating ability of the counterion increase. The counterion is located close to the diimine in both solution and the solid state but it moves toward the palladium as the steric hindrance in the apical positions decreases. When the latter is small the counterion competes with the substrate for apical coordination, and consequently it affects the productivity. In the case of ortho -dimethyl-substituted ligands the counterion is confined in the back, above the NC(R,)C(R,)N moiety, and does not affect the productivity. However, it contributes to increasing the stereoregularity of the copolymer by making the aryl moieties more rigid. With R,=Me and Ar=o -Me2C6H3 an ll of 81,% and 72,% was obtained with X,=CF3SO3, or BArF,, respectively. The isotacticity of the copolymers produced by ortho -monosubstituted catalysts depends greatly on the counterion and ranges from 30,% to 59,% with X,=BArF, and X,=CF3SO3,, respectively, with Ar=o -EtC6H4 and R,=Me. Based on the interionic structural results, this effect can be explained by a greater reduction of the copolymerization rate of Cs -symmetric isomers with respect to their C2 -symmetric counterparts. [source] Emotion,Cognition Interplay in Motivating and Guiding Plans and Actions: Commentary on McClure-Tone's Socioemotional Functioning in Bipolar DisorderCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 2 2009Carroll E. Izard McClure-Tone (2009) focused on the role of two aspects of emotion knowledge (emotion expression recognition and labeling) and on emotion regulation in bipolar disorder (BD). We encourage further research on these and on other components of emotion knowledge that probably play equally significant roles in normal and abnormal development, and perhaps particularly in BD. Despite the author finding serious gaps in the literature, it was shown that we have learned a lot about differences in neural, cognitive, and behavioral processes in children and adolescents with BD and same-age normal individuals, and that much remains unknown. We join the author in encouraging more clinical, developmental, and longitudinal research on emotion processes in BD, particularly theoretically driven studies on some neglected emotion schemas that may prove relatively distinct to the disorder. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||