996 resultados para Dependent Schrodinger-equation
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Polycystic kidney diseases result from disruption of the genetically defined program that controls the size and geometry of renal tubules. Cysts which frequently arise from the collecting duct (CD) result from cell proliferation and fluid secretion. From mCCD(cl1) cells, a differentiated mouse CD cell line, we isolated a clonal subpopulation (mCCD-N21) that retains morphogenetic capacity. When grown in three-dimensional gels, mCCD-N21 cells formed highly organized tubular structures consisting of a palisade of polarized epithelial cells surrounding a cylindrical lumen. Subsequent addition of cAMP-elevating agents (forskolin or cholera toxin) or of membrane-permeable cAMP analogs (CPT-cAMP) resulted in rapid and progressive dilatation of existing tubules, leading to the formation of cystlike structures. When grown on filters, mCCD-N21 cells exhibited a high transepithelial resistance as well as aldosterone- and/or vasopressin-induced amiloride-sensitive and -insensitive current. The latter was in part inhibited by Na(+)-K(+)-2Cl(-) cotransporter (bumetanide) and chloride channel (NPPB) inhibitors. Real-time PCR analysis confirmed the expression of NKCC1, the ubiquitous Na(+)-K(+)-2Cl(-) cotransporter and cystic fibrosis transmembrane regulator (CFTR) in mCCD-N21 cells. Tubule enlargement and cyst formation were prevented by inhibitors of Na(+)-K(+)-2Cl(-) cotransporters (bumetanide or ethacrynic acid) or CFTR (NPPB or CFTR inhibitor-172). These results further support the notion that cAMP signaling plays a key role in renal cyst formation, at least in part by promoting chloride-driven fluid secretion. This new in vitro model of tubule-to-cyst conversion affords a unique opportunity for investigating the molecular mechanisms that govern the architecture of epithelial tubes, as well as for dissecting the pathophysiological processes underlying cystic kidney diseases.
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D-3 Dependent Adult Abuse Report
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Aim Macroevolutionary patterns and processes change substantially depending on levels of taxonomic and ecological organization, and the resolution of environmental and spatial variability. In comparative methods, the resolution of environmental and spatial variability often defines the number of selective regimes used to test whether phenotypic characteristics are adaptively correlated with the environment. Here, we examine how investigator choice of the number of selective regimes, determined by varying the resolution of among-species variability in the species climatic niche (hereafter called ecological scale'), influences trait morphological diversification among Eriogonoideae species. We assess whether adaptive or neutral processes drive the evolution of several morphological traits in these species. Location South-western North America. Methods We applied a phylogenetic framework of three evolutionary models to four morphological traits and the climatic niches of Eriogonoideae (in the buckwheat family, Polygonaceae). We tested whether morphological traits evolve in relation to climate by adaptive or neutral process, and whether the resulting patterns of morphological variability are conserved or convergent across the clade. We inspected adaptive models of evolution under different levels of resolution of among-species variability of the climatic niche. Results We show that morphological traits and climate niches of Eriogonoideae species are not phylogenetically conserved. Further, adaptive evolution of phenotypic traits is specific to climatic niche occupancy across this clade. Finally, the likely evolutionary process and the level of detectable niche conservatism change depending on the resolution of environmental variability of the climatic niche. Main conclusions Our study demonstrates the need to consider both the resolution of environmental variability and alternative evolutionary models to understand the morphological diversification that accompanies divergent adaptive evolution of lineages to climatic conditions.
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On February 17, 2009, Governor Culver signed Executive Order No. 11 to create a Task Force on Dependent Adults with Mental Retardation. The executive order charges the Task Force with the responsibility of recommending steps to strengthen and improve state laws and regulations on the care and treatment of dependent adults with mental retardation. The Final Report includes recommendations that establish or improve systems of coordination between government entities. The report includes a series of proposals from the Department of Human Services (DHS) that redesign the adult abuse assessment process that are necessary for long-term reform. Included in them is a proposal to enhance a community’s capacity to provide a safety net of services, as well as formal and informal supports for vulnerable adults through partnerships among multiple local stakeholders.
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Expression of AtPHO1;H10, a member of the Arabidopsis (Arabidopsis thaliana) PHO1 gene family, is strongly induced following numerous abiotic and biotic stresses, including wounding, dehydration, cold, salt, and pathogen attack. AtPHO1;H10 expression by wounding was localized to the cells in the close vicinity of the wound site. AtPHO1;H10 expression was increased by application of the jasmonic acid (JA) precursor 12-oxo-phytodienoic acid (OPDA), but not by JA or coronatine. Surprisingly, induction of AtPHO1;H10 by OPDA was dependent on the presence of CORONATINE INSENSITIVE1 (COI1). The induction of AtPHO1;H10 expression by wounding and dehydration was dependent on COI1 and was comparable in both the wild type and the OPDA reductase 3-deficient (opr3) mutant. In contrast, induction of AtPHO1;H10 expression by exogenous abscisic acid (ABA) was independent of the presence of either OPDA or COI1, but was strongly decreased in the ABA-insensitive mutant abi1-1. The involvement of the ABA pathway in regulating AtPHO1;H10 was distinct between wounding and dehydration, with induction of AtPHO1;H10 by wounding being comparable to wild type in the ABA-deficient mutant aba1-3 and abi1-1, whereas a strong reduction in AtPHO1;H10 expression occurred in aba1-3 and abi1-1 following dehydration. Together, these results reveal that OPDA can modulate gene expression via COI1 in a manner distinct from JA, and independently from ABA. Furthermore, the implication of the ABA pathway in coregulating AtPHO1;H10 expression is dependent on the abiotic stress applied, being weak under wounding but strong upon dehydration
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Rock-paper-scissors (RPS) dynamics, which maintain genetic polymorphisms over time through negative frequency-dependent (FD) selection, can evolve in short-lived species with no generational overlap, where they produce rapid morph frequency cycles. However, most species have overlapping generations and thus, rapid RPS dynamics are thought to require stronger FD selection, the existence of which yet needs to be proved. Here, we experimentally demonstrate that two cumulative selective episodes, FD sexual selection reinforced by FD selection on offspring survival, generate sufficiently strong selection to generate rapid morph frequency cycles in the European common lizard Zootoca vivipara, a multi-annual species with major generational overlap. These findings show that the conditions required for the evolution of RPS games are fulfilled by almost all species exhibiting genetic polymorphisms and suggest that RPS games may be responsible for the maintenance of genetic diversity in a wide range of species.
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Generating a diverse T cell memory population through vaccination is a promising strategy to overcome pathogen epitope variability and tolerance to tumor Ags. The effector and memory pool becomes broad in TCR diversity by recruiting high- and low-affinity T cells. We wanted to determine which factors dictate whether a memory T cell pool has a broad versus focused repertoire. We find that inflammation increases the magnitude of low- and high-affinity T cell responses equally well, arguing against a synergistic effect of TCR and inflammatory signals on T cell expansion. We dissect the differential effects of TCR signal strength and inflammation and demonstrate that they control effector T cell survival in a bim-dependent manner. Importantly, bim-dependent cell death is overcome with a high Ag dose in the context of an inflammatory environment. Our data define the framework for the generation of a broad T cell memory pool to inform future vaccine design.
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Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is known as a "death ligand"-a member of the TNF superfamily that binds to receptors bearing death domains. As well as causing apoptosis of certain types of tumor cells, TRAIL can activate both NF-kappaB and JNK signalling pathways. To determine the role of TGF-beta-Activated Kinase-1 (TAK1) in TRAIL signalling, we analyzed the effects of adding TRAIL to mouse embryonic fibroblasts (MEFs) derived from TAK1 conditional knockout mice. TAK1-/- MEFs were significantly more sensitive to killing by TRAIL than wild-type MEFs, and failed to activate NF-kappaB or JNK. Overexpression of IKK2-EE, a constitutive activator of NF-kappaB, protected TAK1-/- MEFs against TRAIL killing, suggesting that TAK1 activation of NF-kappaB is critical for the viability of cells treated with TRAIL. Consistent with this model, TRAIL failed to induce the survival genes cIAP2 and cFlipL in the absence of TAK1, whereas activation of NF-kappaB by IKK2-EE restored the levels of both proteins. Moreover, ectopic expression of cFlipL, but not cIAP2, in TAK1-/- MEFs strongly inhibited TRAIL-induced cell death. These results indicate that cells that survive TRAIL treatment may do so by activation of a TAK1-NF-kappaB pathway that drives expression of cFlipL, and suggest that TAK1 may be a good target for overcoming TRAIL resistance.
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We present a unified geometric framework for describing both the Lagrangian and Hamiltonian formalisms of regular and non-regular time-dependent mechanical systems, which is based on the approach of Skinner and Rusk (1983). The dynamical equations of motion and their compatibility and consistency are carefully studied, making clear that all the characteristics of the Lagrangian and the Hamiltonian formalisms are recovered in this formulation. As an example, it is studied a semidiscretization of the nonlinear wave equation proving the applicability of the proposed formalism.
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Nicotine cessation programmes in Switzerland, which are commonly based on the stage of change model of Prochaska and DiClemente (1983), are rarely offered to patients with illicit drug dependence. This stands in contrast to the high smoking rates and the heavy burden of tobacco-related problems in these patients. The stage of change was therefore assessed by self-administered questionnaire in 100 inpatients attending an illegal drug withdrawal programme. Only 15% of the patients were in the contemplation or decision stage. 93% considered smoking cessation to be difficult or very difficult. These data show a discrepancy between the motivation to change illegal drug consumption habits and the motivation for smoking cessation. The high proportion of patients remaining in the precontemplation stage for smoking cessation, in spite of their motivation for illicit drug detoxification, may be due to the perception that cessation of smoking is more difficult than illicit drug abuse cessation.
Phenotypic switching in Pseudomonas brassicacearum involves GacS- and GacA-dependent Rsm small RNAs.
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The plant-beneficial bacterium Pseudomonas brassicacearum forms phenotypic variants in vitro as well as in planta during root colonization under natural conditions. Transcriptome analysis of typical phenotypic variants using microarrays containing coding as well as noncoding DNA fragments showed differential expression of several genes relevant to secondary metabolism and of the small RNA (sRNA) genes rsmX, rsmY, and rsmZ. Naturally occurring mutations in the gacS-gacA system accounted for phenotypic switching, which was characterized by downregulation of antifungal secondary metabolites (2,4-diacetylphloroglucinol and cyanide), indoleacetate, exoenzymes (lipase and protease), and three different N-acyl-homoserine lactone molecules. Moreover, in addition to abrogating these biocontrol traits, gacS and gacA mutations resulted in reduced expression of the type VI secretion machinery, alginate biosynthesis, and biofilm formation. In a gacA mutant, the expression of rsmX was completely abolished, unlike that of rsmY and rsmZ. Overexpression of any of the three sRNAs in the gacA mutant overruled the pleiotropic changes and restored the wild-type phenotypes, suggesting functional redundancy of these sRNAs. In conclusion, our data show that phenotypic switching in P. brassicacearum results from mutations in the gacS-gacA system.
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Xenopus laevis oocytes were used to assay for trans-acting factors shown previously to be involved in the liver-specific regulation of the vitellogenin genes in vitro. To this end, crude liver nuclear extracts obtained from adult estrogen-induced Xenopus females were fractionated by heparin-Sepharose chromatography using successive elutions with 0.1, 0.35, 0.6, and 1.0 M KCl. When these four fractions were injected into oocytes, only the 0.6-M KCl protein fraction significantly stimulated mRNA synthesis from the endogenous B class vitellogenin genes. This same fraction induced estrogen-dependent in vitro transcription from the vitellogenin B1 promoter, suggesting that it contains at least a minimal set of basal transcription factors as well as two positive factors essential for vitellogenin in vitro transcription, i.e. the NF-I-like liver factor B and the estrogen receptor (ER). The presence of these two latter factors was determined by footprinting and gel retardation assays, respectively. In contrast, injection of an expression vector carrying the sequence encoding the ER was unable to activate transcription from the oocyte chromosomal vitellogenin genes. This suggests that the ER alone cannot overcome tissue-specific barriers and that one or several additional liver components participate in mediating tissue-specific expression of the vitellogenin genes. In this respect, we present evidence that the oocyte germinal vesicles contain an NF-I-like activity different from that found in hepatocytes of adult frogs. This observation might explain the lack of vitellogenin gene activation in oocytes injected with the ER cDNA only.
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D-3 Dependent Adult Abuse Report
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Since nitric oxide (NO) participates in the renal regulation of blood pressure, in part, by modulating transport of Na(+) and Cl(-) in the kidney, we asked whether NO regulates net Cl(-) flux (JCl) in the cortical collecting duct (CCD) and determined the transporter(s) that mediate NO-sensitive Cl(-) absorption. Cl(-) absorption was measured in CCDs perfused in vitro that were taken from aldosterone-treated mice. Administration of an NO donor (10 μM MAHMA NONOate) reduced JCl and transepithelial voltage (VT) both in the presence or absence of angiotensin II. However, reducing endogenous NO production by inhibiting NO synthase (100 μM N(G)-nitro-l-arginine methyl ester) increased JCl only in the presence of angiotensin II, suggesting that angiotensin II stimulates NO synthase activity. To determine the transport process that mediates NO-sensitive changes in JCl, we examined the effect of NO on JCl following either genetic ablation or chemical inhibition of transporters in the CCD. Since the application of hydrochlorothiazide (100 μM) or bafilomycin (5 nM) to the perfusate or ablation of the gene encoding pendrin did not alter NO-sensitive JCl, NO modulates JCl independent of the Na(+)-dependent Cl(-)/HCO3(-) exchanger (NDCBE, Slc4a8), the A cell apical plasma membrane H(+)-ATPase and pendrin. In contrast, both total and NO-sensitive JCl and VT were abolished with application of an epithelial Na(+) channel (ENaC) inhibitor (3 μM benzamil) to the perfusate. We conclude that NO reduces Cl(-) absorption in the CCD through a mechanism that is ENaC-dependent.
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Mutation of the nuclear receptor peroxisome proliferator-activated receptor beta/delta (PPARbeta/delta) severely affects placenta development, leading to embryonic death at embryonic day 9.5 (E9.5) to E10.5 of most, but not all, PPARbeta/delta-null mutant embryos. While very little is known at present about the pathway governed by PPARbeta/delta in the developing placenta, this paper demonstrates that the main alteration of the placenta of PPARbeta/delta-null embryos is found in the giant cell layer. PPARbeta/delta activity is in fact essential for the differentiation of the Rcho-1 cells in giant cells, as shown by the severe inhibition of differentiation once PPARbeta/delta is silenced. Conversely, exposure of Rcho-1 cells to a PPARbeta/delta agonist triggers a massive differentiation via increased expression of 3-phosphoinositide-dependent kinase 1 and integrin-linked kinase and subsequent phosphorylation of Akt. The links between PPARbeta/delta activity in giant cells and its role on Akt activity are further strengthened by the remarkable pattern of phospho-Akt expression in vivo at E9.5, specifically in the nucleus of the giant cells. In addition to this phosphatidylinositol 3-kinase/Akt main pathway, PPARbeta/delta also induced giant cell differentiation via increased expression of I-mfa, an inhibitor of Mash-2 activity. Finally, giant cell differentiation at E9.5 is accompanied by a PPARbeta/delta-dependent accumulation of lipid droplets and an increased expression of the adipose differentiation-related protein (also called adipophilin), which may participate to lipid metabolism and/or steroidogenesis. Altogether, this important role of PPARbeta/delta in placenta development and giant cell differentiation should be considered when contemplating the potency of PPARbeta/delta agonist as therapeutic agents of broad application.