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Three effective medium theories (Maxwell-Garnett Theory, MGT; Bruggeman Effective Medium Theory, BEMT; and Coherent Model Approximation, CMA) are applied to predict magnetic susceptibility of polymer-magnetic particle composites and composite resonant frequency. Predictions are compared to the measurement of multi-crystalline magnetic particulate-polymer composites. Particulates had aspect ratios near unity; bulk low frequency susceptibilities ranged from 27 to 1000 s and particle volume fractions were between 5% and 100%. Emphasis was placed on CMA and BEMT. BEMT was selected for incorporation of a scaling function relating demagnetization with particulate concentration. The scaled model is scaled effective medium theory (ScEMT). Percolation theory and micromagnetic computations were applied to guide the choice of scaling function parameters. Experimental support of scale model physics was taken from measurements of magnetic sphere clustering in two dimensions. Scaling function constants and power laws were determined by numerical fits to one set of high susceptibility, Ni0.24 Zn0.65 Cu0.07 Fe2.04O4 particle composites. The parameters of the scaling function were held constant and then applied to predict magnetic parameters in other composites. These included Fe, Fe-Ni, Ni0.34 Zn0.65Fe2.0O4, Mn0.53Zn0.4Fe2.06O4, NiMn0.02Fe2O4, and Fe3O4. ScEMT predictions and measurement were in good agreement. When combined with Snoek's law, the combined model improved predictions of resonant frequency in composites and relaxation frequency predictions are in progress. Overall, ScEMT shows improved accuracy for calculating low frequency susceptibility and composite resonant frequency. [ABSTRACT FROM AUTHOR]

Background: Delayed time from collection to centrifugation may cause erroneously high lactate levels in vitro (from continued blood cell metabolism under anaerobic conditions in the collection tube) if not collected in appropriate collection devices, consequently increasing the risk for inappropriate patient care or harm. We undertook a study to determine the turnaround time for lactate testing in a tertiary care setting and also performed short- and long-term lactate stability studies in blood collected in sodium fluoride/potassium oxalate (NaF/KOx) collection tubes. Methods: The hospital lab information system was mined for 6 months to determine patient samples that may have exceeded the time from collection-to-receival in lab of 15-min. Lactate stability was evaluated in unspun NaF/KOx collection tubes at 15 min intervals for to 2 h; and separately at 2, 6, 12, 24, and 48-h post-collection. Results: A total of 8,929 plasma samples were collected in 6 months, and 1/3 were not received in the lab within 15 min from collection. In NaF/KOx additive, lactate levels had minor increases over 2 h, and incremental increases at an average rate of 0.0035 mmol/L/h over 48 h with maximum increase of 9.8% at 48 h. However, the average change across all time points were within local allowable performance goals (at ≤4 mmol/L ± 0.5 mmol/L; at >4 mmol/L ± 12%). Conclusion: A small proportion of lactate specimens may experience delay in processing. Although lactate levels may incrementally increase over 48-h at room temperature in unspun NaF/KOx collection tubes, the changes may not be clinically impactful. [ABSTRACT FROM AUTHOR]

The Handmaid's Tale is a novel by Margaret Atwood that has won numerous awards for its frightful dystopian imagery. It was recently adapted for series television, an adaptation that has led some to see beyond the confines of the printed word. Columnists for a number of newspapers and magazines have suggested the television series provides insights into contemporary politics and religion. This study examines the way these essayists wrestled with various interpretations of the show. Some writers based their fearful reaction to the show on the Trump administration. Others, though, scoffed at this interpretation and seemed to enjoy doing so. In this study I examine how these dissonant interpretations might raise very good questions about how scholars think about media, religion, and fear. [ABSTRACT FROM AUTHOR]

Three effective medium theories (Maxwell-Garnett, MGT; Bruggeman, BEMT; Coherent Model Approximation, CMA) are often applied to predict dielectric or magnetic susceptibility of polymer-magnetic particle composites. Measured composite susceptibility data for multi-crystalline magnetic particulate aspect ratios near unity and bulk low frequency susceptibilities ranging from 10s to 1000s were used to evaluate EMT model accuracies. Composite volume fractions varied from 5 to 100%. Each theory was evaluated against measured data with emphasis placed on CMA and BEMT. BEMT was selected for incorporation of a scaling function relating demagnetization factors with particulate fraction. The scaled model is ScEMT. Percolation theory and micromagnetic computations were applied as guides in choice of scaling function numerical parameters. Experimental support of scale model physics was taken from measurements of magnetic sphere clustering in two dimensions. Scaling function parameters were determined by a numerical fit to one set of NiZnCuFerrite particle composites. The parameters of the scaling function were held constant and then applied to predict magnetic parameters in others. Those composites incorporated: Fe, Fe-Ni, Ni.34 Zn.65 ferrites; Mn.53 Zn.41 ferrites; NiMn.02 ferrites and Fe3O4. Scaled effective model, ScEMT, and measurement were in good agreement. When combined with Snoek's law, the combined model improved predictions of resonant frequency in composites and relaxation frequency predictions are in progress. Overall, ScEMT shows improved accuracy for calculating low frequency susceptibility and also composite resonant frequency. [ABSTRACT FROM AUTHOR]

In 2017 Nike, Inc. announced the launch of a new product, a pro hijab. Journalistic coverage of this event allows for analysis of how news reporters balance their view of religion with predispositions to cover other important elements, such as women in sport, and the growth of corporate power. Through a critical discourse analysis, the researcher discovered reporters did not manifest strong Islamophobia or patriarchy in their coverage and that they rarely questioned Nike's corporate power. [ABSTRACT FROM AUTHOR]

Humor is widely used as a means of supporting group solidarity, but what determines the direction that this humor takes (i.e. its quality and targets)? I suggest that the answer lies in an interaction between self-concept, perceptions of outgroups and micro group culture. Aspects of self-concept that are central for a group's identity work, especially how the group imagines outsiders, open possibilities for certain types of humor while closing off others. Then micro-cultural processes, heavily dependent on the exact persons present in a given interaction, influence the humorous forms used. This process explains why groups in roughly similar structural positions often make use of humor to generate solidarity in strikingly different ways, as well as why styles of humor vary, within limits, within groups. I provide illustrations of this process in two religious minority groups with very different humorous styles: atheists in the Bible Belt and evangelical Christians in Chicago. [ABSTRACT FROM AUTHOR]

This study examines how mainstream news media reported the withdrawal of a popular pastor from the 2013 Obama inaugural ceremony. Louie Giglio was originally chosen for a role in the event but relinquished his position when focus was placed on a sermon he once delivered about homosexuality. Analysis of framing and sourcing of the stories raises serious questions about the role media played in reporting about this skirmish, which is clearly part of the larger culture wars. [ABSTRACT FROM AUTHOR]

A recent study of a magazine distributed by a powerful conservative Christian group determined the organization showed strong concern for “visual culture.” The publication directed its readers on how to understand the seen world. The present study analyzes a periodical of an avowedly secular group to understand how they might manifest similar or different concerns. On the whole, the content of the magazine calledThe Humanistappears to indicate that visual culture is as important to agnostics as it is to theists. [ABSTRACT FROM PUBLISHER]

KCNK1, a member of the family of two-pore K+ ion channels, is specifically induced in the livers of male mice after phenobarbital treatment. Here, we have determined the molecular mechanism of this male-specific activation of the Kcnk1 gene and characterized KCNK1 as a phenobarbital-inducible antihyperplasia factor. Upon activation by phenobarbital, nuclear receptor CAR binds the 97-bp response element (−2441/−2345) within the Kcnk1 promoter. This binding is observed in the livers of male mice, but not in the livers of female mice and requires the pituitary gland, because hypophysectomy abrogates it. Hyperplasia further progressed in the livers of Kcnk1−/− male mice compared with those of Kcnk1+/+ males after phenobarbital treatment. Thus, KCNK1 suppresses phenobarbital-induced hyperplasia. These results indicate that phenobarbital treatment induces KCNK1 to elicit a male-specific and growth-suppressing signal. Thus, KCNK1 and Kcnk1−/− mice provide an experimental tool for further investigation into the molecular mechanism of CAR-mediated promotion of the development of hepatocellular carcinoma in mice. [ABSTRACT FROM AUTHOR]

Aims Circulating endogenous, dietary, and foreign chemicals can contribute to vascular dysfunction. The mechanism by which the vasculature protects itself from these chemicals is unknown. This study investigates whether the pregnane X receptor (PXR), the major transcriptional regulator of hepatic drug metabolism and transport that responds to such xenobiotics, mediates vascular protection by co-ordinating a defence gene programme in the vasculature. Methods and results PXR was detected in primary human and rat aortic endothelial and smooth muscle cells (SMC) and blood vessels including the human and rat aorta. Metabolic PXR target genes cytochrome P450 3A, 2B, 2C, and glutathione S-transferase mRNA and activity were induced by PXR ligands in rodent and human vascular cells and absent in the aortas from PXR-null mice stimulated in vivo or in rat aortic SMC expressing dominant-negative PXR. Activation of aortic PXR by classical agonists had several protective effects: increased xenobiotic metabolism demonstrated by bioactivation of the pro-drug clopidogrel, which reduced adenosine diphosphate-induced platelet aggregation; increased expression of multidrug resistance protein 1, mediating chemical efflux from the vasculature; and protection from reactive oxygen species-mediated cell death. Conclusion PXR co-ordinately up-regulates drug metabolism, transport, and antioxidant genes to protect the vasculature from endogenous and exogenous insults, thus representing a novel gatekeeper for vascular defence. [ABSTRACT FROM AUTHOR]

Phenobarbital (PB), a nongenotoxic carcinogen, activates the nuclear constitutive active/androstane receptor (CAR), resulting in the transcriptional induction or repression of various hepatic genes. We previously demonstrated that liver tumors developed after chronic PB treatment only when CAR is present. To understand the molecular mechanism of tumor promotion, cDNA microarray analysis was performed. We identified tubulin alpha 8 (TUBA8) as one of the candidate genes that may be involved in liver tumor promotion. Tuba8 mRNA was induced with PB treatment in mouse livers before tumor development as well as in tumor tissues. Because the functions of TUBA8 are unknown in liver, we investigated the effects of TUBA8 gene expression on cell growth, proliferation, and cell migration. Sense or antisense cDNA for Tuba8 was stably transfected into Huh7 and HepG2 cells. Exogenous overexpression of Tuba8 inhibited cell growth and proliferation in Huh7 but not in HepG2 cells, while cell migration was increased in HepG2 cells but not Huh7 cells. These results indicate that TUBA8 can play a role in the regulation of cell growth, proliferation, and cell migration in a cell-specific manner in vitro, suggesting that TUBA8 may contribute to mouse liver tumorigenesis through these functions. [ABSTRACT FROM AUTHOR]

Background: Phenobarbital (PB) is the most well-known among numerous non-genotoxic carcinogens that cause the development of hepatocellular carcinoma (HCC). PB activates nuclear xenobiotic receptor Constitutive Active/Androstane Receptor (CAR; NR1I3) and this activation is shown to determine PB promotion of HCC in mice. The molecular mechanism of CAR-mediated tumor promotion, however, remains elusive at the present time. Here we have identified Growth Arrest and DNA Damage-inducible 45β (GADD45B) as a novel CAR target, through which CAR represses cell death. Methodology/Principal Findings: PB activation of nuclear xenobiotic receptor CAR is found to induce the Gadd45b gene in mouse liver throughout the development of HCC as well as in liver tumors. Given the known function of GADD45B as a factor that represses Mitogen-activated protein Kinase Kinase 7 - c-Jun N-terminal Kinase (MKK7-JNK) pathway-mediated apoptosis, we have now demonstrated that CAR interacts with GADD45B to repress Tumor Necrosis Factor α ( TNFα)-induced JNK1 phosphorylation as well as cell death. Primary hepatocytes, prepared from Car+/+, Car−/−, Gadd45b+/+ and Gadd45b−/− mice, were treated with TNFα and Actinomycin D to induce phosphorylation of JNK1 and cell death. Co-treatment with the CAR activating ligand TCPOBOP (1,4 bis[2-(3,5-dichloropyridyloxy)]benzene) has resulted in repression of both phosphorylation and cell death in the primary hepatocytes from Car+/+ but not Car−/− mice. Repression by TCPOBOP was not observed in those prepared from Gadd45b−/− mice. In vitro protein-protein interaction and phosphorylation assays have revealed that CAR interacts with MKK7 and represses the MKK7-mediated phosphorylation of JNK1. Conclusions/Significance: CAR can form a protein complex with GADD45B, through which CAR represses MKK7-mediated phosphorylation of JNK1. In addition to activating the Gadd45b gene, CAR may repress death of mouse primary hepatocytes by forming a GADD45B complex and repressing MKK7-mediated phosphorylation of JNK1. The present finding that CAR can repress cell death via its interaction with GADD45B provides an insight for further investigations into the CAR-regulated molecular mechanism by which PB promotes development of HCC. [ABSTRACT FROM AUTHOR]

We previously found that the lack of nuclear xenobiotic receptor, PXR, decreases femoral bone mineral density (BMD) in Pxr-/- mice. Our present study aims to elucidate the inherited phenotype that correlates with the decreased BMD and to identify the PXR-regulated gene that may link with this phenotype.Pxr+/+ and Pxr-/- mice were used to measure the serum levels of inorganic phosphate (Pi), calcium and vitamin D3. Real time PCR and western blots were used to determine the intestinal and renal expressions of Pi and calcium transporters and various other genes involved in bone homeostasis. Cell-based reporter and gel shift assays were performed to characterize the promoter of the identified PXR-regulated gene.In both Pxr-/- male and female mice, lumbar, sternum, and skull were all also found to have decreased their BMD values. Serum Pi levels, but not calcium levels, are attenuated in Pxr-/- mice, exhibiting a phenotype of hypophosphatemia. Among the members of the Na/Pi contransporter family, only the SLC34A2 mRNA and protein are repressed in Pxr-/- mice. PXR can directly activate the transcription of the SLC34A2 gene through an ER6 motif on its promoter.Pxr-/- mice show the inherited phenotype of hypophosphatemia. The lack of PXR results in a severe repression of the Na/Pi cotransporter NaPi-IIb/Npt2b (SLC34A2), thus leading Pxr-/- males and females to develop a type of hypophosphatemia. [ABSTRACT FROM AUTHOR]

Upon drug activation, the nuclear pregnane X receptor (PXR) regulates not only hepatic drug but also energy metabolism. Using Pxr-/- mice, we have now investigated the PXR-mediated repression of lipid metabolism in the fasting livers. Treatment with PXR activator pregnenolone 16α-carbonitrile (PCN) down-regulated the mRNA levels of carnitine palmitoyltransferase 1A (in β-oxidation) and mitochondrial 3-hydroxy-3-methylglutarate-CoA synthase 2 (in ketogenesis) in wild-type (Pxr+/+) mice only. In contrast, the stearoyl-CoA desaturase 1 (in lipogenesis) mRNA was up-regulated in the PCN-treated Pxr+/+ mice. Reflecting these up- and down-regulations and consistent with decreased energy metabolism, the levels of hepatic triglycerides and of serum 3-hydroxybutylate were increased and decreased, respectively, in the PCN-treated Pxr+/+ mice. Using gel shift, glutathione S-transferase pull-down and cell-based reporter assays, we then examined whether PXR could cross-talk with the insulin response forkhead factor FoxA2 to repress the transcription of the Cpt1a and Hmgcs2 genes, because FoxA2 activates these genes in fasting liver. PXR directly bound to FoxA2 and repressed its activation of the Cpt1a and Hmgcs2 promoters. Moreover, Chip assays showed that PCN treatment attenuated the binding of FoxA2 to these promoters in fasting Pxr+/+ but not Pxr-/- mice. These results are consistent with the conclusion that PCN-activated PXR represses FoxA2-mediated transcription of Ctp1a and Hmgcs2 genes in fasting liver. [ABSTRACT FROM AUTHOR]

Estrogens are known to cause hepatotoxicity such as intrahepatic cholestasis in susceptible women during pregnancy, after administration of oral contraceptives, or during postmenopausal replacement therapy. Enterohepatic nuclear receptors including farnesoid X receptor (FXR), pregnane X receptor (PXR), and constitutive active/androstane receptor (CAR) are important in maintaining bile acid homeostasis and protecting the liver from bile acid toxicity. However, no nuclear receptor has been implicated in the mechanism for estrogen-induced hepatotoxicity. Here Era-/-, Erb-/-, Fxr-/-, Pxr-/-, and Car-/- mice were employed to show that Erα-/- mice were resistant to synthetic estrogen 17α-ethynylestradiol (EE2)-induced hepatotoxicity as indicated by the fact that the EE2-treated Erα-/- mice developed none of the hepatotoxic phenotypes such as hepatomegaly, elevation in serum bile acids, increase of alkaline phosphatase activity, liver degeneration, and inflammation. Upon EE2 treatment, estrogen receptor a (ERα) repressed the expression of bile acid and cholesterol transporters (bile salt export pump (BSEP), Na+/taurocholate cotransporting polypeptide (NTCP), OATP1, OATP2, ABCG5, and ABCG8) in the liver. Consistently, biliary secretions of both bile acids and cholesterol were markedly decreased in EE2-treated wild-type mice but not in the EE2-treated Erα-/- mice. In addition, ERα up-regulated the expression of CYP7B1 and down-regulated the CYP7A1 and CYP8B1, shifting bile acid synthesis toward the acidic pathway to increase the serum level of β-muricholic acid. ERβ, FXR, PXR, and CAR were not involved in regulating the expression of bile acid transporter and biosynthesis enzyme genes following EE2 exposure. Taken together, these results suggest that ERα-mediated repression of hepatic transporters and alterations of bile acid biosynthesis may contribute to development of the EE2-induced hepatotoxicity. [ABSTRACT FROM AUTHOR]

Although at one level Jean-Pierre Jeunet's Le Fabuleux Destin d'Amélie Poulain is a sweet, attractive film about a young Parisian doing good deeds, it also offers a compelling analysis of the role of technology in our modern lives. The film paints a world where machines and a mechanistic worldview are appealing because humans have a desire to control their destinies but threatening because humans value freedom. The work of French social theorist Jacques Ellul is especially useful in analyzing these facets of the film as technology and freedom were consistent themes in his various books on the modern milieu. [ABSTRACT FROM AUTHOR]

Abstract: The nuclear receptor constitutive active/androstane receptor CAR is a drug-sensing transcription factor. Upon activation by various drugs such as phenobarbital (PB), CAR translocates from the cytoplasm into the nucleus to regulate the genes that encode enzymes and proteins involved in hepatic metabolism. Here, we have shown the presence of CAR at the cell membrane of mouse livers, using Car +/+ and Car −/− mice. Levels of the cell membrane CAR increased after PB treatment. The CAR exists as a large approximately 160kDa complex. Thus, CAR undergoes PB-induced translocation to the cell membrane, indicating that CAR may exert a non-genomic action. [Copyright &y& Elsevier]

This paper describes a methodology to assess health/medical informatics graduate-level education curricula. The authors used the Certified Professional in Healthcare Information Management Systems (CPHIMS) exam objectives published by the Healthcare Information and Management Systems Society (HIMSS) as the basis for their assessment. The authors compared the 69 CPHIMS exam objectives against four health/medical informatics program course objectives as stated in the selected program’s online graduate catalog. Results showed that the two programs with management as a focus addressed the majority (67 and 59%) of the CPHIMS objectives within core and elective courses combined. Overall, the other two programs addressed closer to a third of the CPHIMS objectives (36 and 32%). This methodology could prove to be useful in assisting students interested in graduate-level training programs with a tool by which to measure the congruence of the curricula of different programs with the mission of the programs and with their own professional interests. [Copyright &y& Elsevier]

Silk (1995) proposed in Unsecular Media that journalists operate with a limited series of topoi and that these are borrowed from religion. Silk thus claimed when journalists write about religion, they do so in a way that ultimately supports religious values. In this study, I apply topic analysis to recent news coverage of Jesse Jackson's marital infidelity to determine the extent to which the topos of hypocrisy was employed and whether this employment supported or challenged a religious as opposed to secular world view. [ABSTRACT FROM AUTHOR]

Focuses on how Ellul's theory complicates liberal democracy. Growth of environmental journalism; Role of media in liberal democracy.

Investigates the applicability of liberal irony of philosopher Richard Rorty to environmental journalism. Notion of liberal irony as a reaction to ontology and axiology; Significance of historical contingencies in the field of communication arts; Costs and benefits of Rortyan postmodernism; Implications for environmental reporting.

Proposes the work of Jacques Ellul for reconceptualizing the relationship among the citizen, the media, and the state. Hegemony theory and its modern variants; Ellul's view that the modern state is the product of the invasion of technique throughout society; Role of the social critic.

Why do citizens indicate support for protest movements such as the Tea Party and Occupy Wall Street? There have been two general sets of explanations. One set emphasizes that support comes from those for whom the existing party system, and the ideological differentiation that corresponds to party divisions, are irrelevant. The second set takes the opposite tack, and emphasizes that the only thing that supporters of protests movements find lacking in the party system is extremity. Using some underexplored data, we present evidence that both accounts are incorrect for the case of these recent movements (Occupy and the Tea Party): what provokes support for protest movements is not ideology itself but a fundamental rejection of the current state of the party system, which we call disgruntlement. What ideology does for supporters is provide a sense of political friends and enemies (or near and far), which then can channel the direction that this disgruntlement takes. Further, ideologues with more education are more resistant to the appeal of the protest movement associated with the other political camp. [ABSTRACT FROM AUTHOR]

The article reviews the article "Hospital IT Adoption Strategies Associated with Implementation Success: Implications for Achieving Meaningful Use," by Eric W. Ford, Nir Menachemi, Timothy R. Huerta, and Feliciano Yu which appears in the May 2010 issue of the "Journal of Healthcare Management."

Low glucose stimulated phosphorylation of pregnane X receptor (PXR) at Ser 350 in correlation with an increased gluconeogenesis in human hepatoma-derived HepG2 cells. Only glucose, but neither insulin nor glucagon, stimulated this phosphorylation. Here, serine/threonine kinase, vaccinia related kinase 1 (VRK1)-mediated phosphorylation of PXR is now defined as this glucose-elicited novel signal. In low glucose conditions, VRK1 directly phosphorylates PXR at Ser 350 , enabling PO 3 -PXR to scaffold protein phosphatase PP2Cα. This PP2Cα dephosphorylates serine/threonine kinase 2 (SGK2) at Thr 193 . This dephosphorylation dissociates SGK2 from and actives the phosphoenolpyruvate carboxykinase 1 ( PCK1 ) gene as phosphorylated SGK2 binds and represses the gene. Conversely, VRK1 self-represses its activity to phosphorylate PXR through cyclin-dependent kinase 2 (CDK2) in high glucose conditions, resulting in the repression of the PCK1 gene. This PXR phosphorylation was also observed in fasting mouse livers. Thus, the VRK1-CDK2-PXR-PP2Cα-SGK2 pathway can be a novel physiological cell signaling that regulates gluconeogenesis in response to glucose. [ABSTRACT FROM AUTHOR]

Background:Whereas estrogen receptors are present in immune cells, it is not known if they are phosphorylated to regulate immune cell functions. Here we determined the phosphorylation status of estrogen receptor α (ERα) at residue serine 216 in mouse neutrophils and examined its　role in migration and infiltration. Serine 216 is the conserved phosphorylation site within the DNA binding domains found in the majority of nuclear receptors. Methodology/Principal Findings:A phospho-peptide antibody specific to phosphorylated serine 216 and ERα KO mice were utilized in immunohistochemistry, double immuno-staining or Western blot to detect phosphorylation of ERα in peripheral blood as well as infiltrating neutrophils in the mouse uterus. Transwell assays were performed to examine migration of neutrophils. An anti-Ly6G antibody identified neutrophils. About 20% of neutrophils expressed phosphorylated ERα at serine 216 in peripheral white blood cells (WBC) from C3H/HeNCrIBR females. Phosphorylation was additively segregated between C3H/HeNCrIBR and C57BL/6 females. Only neutrophils that expressed phosphorylated ERα migrated in Transwell assays as well as infiltrated the mouse uterus during normal estrous cycles. Conclusions/Significance:ERα was phosphorylated at serine 216 in about 20% of mouse peripheral blood neutrophils. Only those that express phosphorylated ERα migrate and infiltrate the mouse uterus. This phosphorylation was the first to be characterized in endogenous ERα found in normal tissues and cells. Phosphorylated ERα may have opened a novel research direction for biological roles of phosphorylation in ERα actions and can be developed as a drug target for treatment of immune-related diseases. [ABSTRACT FROM AUTHOR]

Cytoplasmic constitutive active/androstane receptor (CAR) retention protein (CCRP and also known as DNAJC7) is a co-chaperone previously characterized to retain nuclear receptor CAR in the cytoplasm of HepG2 cells. Here we have produced CCRP knockout (KO) mice and demonstrated that CCRP regulates CAR at multiple steps in activation of the cytochrome (Cyp) 2b10 gene in liver: nuclear accumulation, RNA polymerase II recruitment and epigenetic modifications. Phenobarbital treatment greatly increased nuclear CAR accumulation in the livers of KO males as compared to those of wild type (WT) males. Despite this accumulation, phenobarbital-induced activation of the Cyp2b10 gene was significantly attenuated. In ChIP assays, a CAR/retinoid X receptor-α (RXRα) heterodimer binding to the Cyp2b10 promoter was already increased before phenobarbital treatment and further pronounced after treatment. However, RNA polymerase II was barely recruited to the promoter even after phenobarbital treatment. Histone H3K27 on the Cyp2b10 promoter was de-methylated only after phenobarbital treatment in WT but was fully de-methylated before treatment in KO males. Thus, CCRP confers phenobarbital-induced de-methylation capability to the promoter as well as the phenobarbital responsiveness of recruiting RNA polymerase II, but is not responsible for the binding between CAR and its cognate sequence, phenobarbital responsive element module. In addition, KO males developed steatotic livers and increased serum levels of total cholesterol and high density lipoprotein in response to fasting. CCRP appears to be involved in various hepatic regulations far beyond CAR-mediated drug metabolism. [ABSTRACT FROM AUTHOR]

Compared with its rodent orthologs, little is known about the chemical specificity of human constitutive androstane receptor (hCAR) and its regulation of hepatic enzyme expression. Phenytoin (PHY), a widely used antiepileptic drug, is a potent inducer of CYP2B6 in primary human hepatocytes, but does not activate human pregnane X receptor (PXR) significantly in cellbased transfection assays at the same concentrations associated with potent induction of CYP2B6. Based on this observation, we hypothesized that PHY may be a selective activator of hCAR. In primary human hepatocytes, expression of CYP2B6 reporter genes containing phenobarbital-responsive enhancer module (PBREM) or PBREM/xenobiotic-responsive enhancer module (XREM) response elements were activated up to 14- and 28-fold, respectively, by 50 µM PHY. By contrast, parallel experiments in HepG2 cell lines co-transfected with an hPXR expression vector did not show increased reporter activity. These results indicated that a PXR-independent pathway, which is retained in primary hepatocytes, is responsible for PHY induction of CYP2B6. Further experiments revealed that PHY effectively translocates hCAR from the cytoplasm into the nucleus in both primary human hepatocytes and CAR-/- mice. Compared with vehicle controls, PHY administration significantly increased CYP2B6 reporter gene expression, when this reporter construct was delivered together with hCAR expression vector into CAR-/- mice. However, PHY did not increase reporter gene expression in CAR-/- mice in the absence of hCAR vector, implying that CAR is essential for mediating PHY induction of CYP2B6 gene expression. Taken together, these observations demonstrate that, in contrast to most of the known CYP2B6 inducers, PHY is a selective activator of CAR in humans. [ABSTRACT FROM AUTHOR]

The nuclear receptor CAR, a phenobarbital (PB)-responsive transcription factor, translocates into the nucleus of hepatocytes after PB induction. In non-induced mice, CAR forms a physical complex with heat shock protein 90 (HSP90) in the cytoplasm. In response to PB induction, protein phosphatase 2A is recruited to the CAR:HSP90 complex. This recruitment may lead CAR to translocate into the nucleus, consistent with the inhibitions of nuclear CAR accumulation in PB-induced mouse primary hepatocytes by okadaic acid as well as by geldanamycin. [Copyright &y& Elsevier]

Background: Estrogen receptor α (ERα) has been suggested to regulate anti-inflammatory signaling in brain microglia, the only resident immune cells in the brain. ERα conserves the phosphorylation motif at Ser216 within the DNA binding domain. Previously, Ser216 was found to be phosphorylated in neutrophils infiltrating into the mouse uterus and to enable ERα to regulate migration. Given the implication of this phosphorylation in immune regulation, ERα was examined in mouse microglia to determine if Ser216 is phosphorylated and regulates microglia's inflammation. It was found that Ser216 was constitutively phosphorylated in microglia and demonstrated that in the absence of phosphorylated ERα in ERα KI brains microglia inflamed, confirming that phosphorylation confers ERα with anti-inflammatory capability. ERα KI mice were obese and weakened motor ability. Methods: Mixed glia cells were prepared from brains of 2-days-old neonates and cultured to mature and isolate microglia. An antibody against an anti-phospho-S216 peptide of ERα (αP-S216) was used to detect phosphorylated ERα in double immunofluorescence staining with ERα antibodies and a microglia maker Iba-1 antibody. A knock-in (KI) mouse line bearing the phosphorylation-blocked ERα S216A mutation (ERα KI) was generated to examine inflammation-regulating functions of phosphorylated ERα in microglia. RT-PCR, antibody array, ELISA and FACS assays were employed to measure expressions of pro- or anti-inflammatory cytokines at their mRNA and protein levels. Rotarod tests were performed to examine motor connection ability. Results: Double immune staining of mixed glia cells showed that ERα is phosphorylated at Ser216 in microglia, but not astrocytes. Immunohistochemistry with an anti-Iba-1 antibody showed that microglia cells were swollen and shortened branches in the substantial nigra (SN) of ERα KI brains, indicating the spontaneous activation of microglia as observed with those of lipopolysaccharide (LPS)-treated ERα WT brains. Pro-inflammatory cytokines were up-regulated in the brain of ERα KI brains as well as cultured microglia, whereas anti-inflammatory cytokines were down-regulated. FACS analysis showed that the number of IL-6 producing and apoptotic microglia increased in those prepared from ERα KI brains. Times of ERα KI mice on rod were shortened in Rotarod tests. Conclusions: Blocking of Ser216 phosphorylation aggravated microglia activation and inflammation of mouse brain, thus confirming that phosphorylated ERα exerts anti-inflammatory functions. ERα KI mice enable us to further investigate the mechanism by which phosphorylated ERα regulates brain immunity and inflammation and brain diseases. Video abstract [ABSTRACT FROM AUTHOR]

Estrogen sulfotransferase (SULT1E1) inactivates estrogen and regulates its metabolic homeostats. Whereas SULT1E1 is expressed low in the liver of adult mice, it is induced by phenobarbital (PB) treatment or spontaneously in diabetic livers via nuclear receptors. Utilizing constitutive active/androstane receptor (CAR) KO, estrogen receptor α (ERα KO, phosphorylation-blocked ERα S216A KI mice, it is now demonstrated that, after being activated by PB, CAR binds and recruits ERα onto the Sulte1 promoter for subsequent phosphorylation at Ser216. This phosphorylation tightens CAR interacting with ERα and to activates the promoter. Hepatic SULT1E1 mRNA levels are constitutively up-regulated in type 1 diabetic Akita mice; CAR spontaneously accumulates in the nucleus and activates the Sult1e1 promoter by recruiting phosphorylated ERα in the liver as observed with PB-induced livers. Thus, this CAR-phosphorylated ERα signaling enables these two nuclear receptors to communicate, activating the Sult1e1 gene in response to either PB or diabetes in mice. ERα phosphorylation may integrate CAR into estrogen actions, providing insights into understanding drug-hormone interactions in clinical therapy. [ABSTRACT FROM AUTHOR]

The estrogen sulfotransferase SULT1E1 sulfates and inactivates estrogen, which is reactivated via desulfation by steroid sulfatase, thus regulating estrogen homeostasis. Phenobarbital (PB), a clinical sedative, activates Sult1e1 gene transcription in mouse livers. Here, the molecular mechanism by which the nuclear receptors CAR, which is targeted by PB, and RORα communicate through phosphorylation to regulate Sult1e1 activation has been studied. RORα, a basal activity repressor of the Sult1e1 promoter, becomes phosphorylated at serine 100 and converts to an activator of the Sult1e1 promoter in response to PB. CAR regulates both the RORα phosphorylation and conversion. Our findings suggest that PB signals CAR to communicate with RORα via serine 100 phosphorylation, converting RORα from transcription repressor to activator of the Sult1e1 gene and inducing SULT1E1 expression in mouse livers. [ABSTRACT FROM AUTHOR]

Much of the Watonwan River tributary system to the upper Mississippi River basin (UMR), and the fluvial systems to which it drains, are listed as impaired under the United States Environmental Protection Agency Clean Water Act303(d) and/or by the Minnesota Pollution Control Agency. In addition, eutrophic conditions and excessive sedimentation rates exist in Lake Pepin, a riverine lake to which the UMR drains. Thus, understanding the hydrogeomorphic change throughout the UMR is vital in order to establish appropriate efforts to mitigate environmental hazards downstream. This study attempts to evaluate hydrogeomorphic change at the watershed scale in the Watonwan River watershed between 1855 and the near present. Historical plat maps, digital elevation models (DEMs), aerial images, soil/topographic characteristics, land-use change, and field surveys are analyzed. Surficial hydrologic features digitized from historical plat maps are compared with contemporary stream networks extracted from high-resolution DEMs. Scale effects are investigated using multi-resolution (1 m, 3 m, 8.5 m, and 30 m) DEMs, with 8.5 m DEMs being ideal for watershed scale analysis, and 1-3 m DEMs being ideal for subwatershed analysis. There has been a substantial hydrogeomorphic change in the watershed since 1855, but most significantly, we interpret that the highest rates of erosion occur in the eastern watershed, where knickzone propagation has produced substantial relief. [ABSTRACT FROM AUTHOR]

The Nuclear receptor CAR (NR1I3) regulates hepatic drug and energy metabolism as well as cell fate. Its activation can be a critical factor in drug-induced toxicity and disease development such as diabetes and tumors. CAR inactivates its constitutive activity by phosphorylation at threonine 38. Utilizing receptor for protein kinase 1 (RACK1) as the regulatory subunit, protein phosphatase PP2A dephosphorylates threonine 38 to activate CAR. Here we have demonstrated that CAR undergoes its homodimer-monomer conversion to regulate this dephosphorylation. By co-expressing two differently-tagged CAR proteins in Huh-7 cells, mouse primary hepatocytes and mouse livers, co-immunoprecipitation and two-dimensional gel electrophoresis revealed that CAR can form a homodimer in a configuration in which the PP2A/RACK1 binding site is buried within its dimer interface. Epidermal growth factor (EGF) was found to stimulate CAR homo-dimerization, thus constraining CAR in its inactive form. The agonistic ligand CITCO binds directly to the CAR homodimer and dissociates phosphorylated CAR into its monomer, exposing the PP2A/RACK1 binding site for dephosphorylation. Phenobarbital, which is not a CAR ligand, binds the EGF receptor, reversing the EGF signal to monomerize CAR for its indirect activation. Thus, the homodimer-monomer conversion is the underlying molecular mechanism that regulates CAR activation, by placing phosphorylated threonine 38 as the common target for both direct and in direct activation of CAR. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ether BDE-47 (2,2′,4,4′-tetrabromodiphenyl ether) is a thyroid hormone disruptor in mice; hepatic induction of various metabolic enzymes and transporters has been suggested as the mechanism for this disruption. Utilizing Car−/− and Pxr−/− mice as well as human primary hepatocytes, here we have demonstrated that BDE-47 activated both mouse and human nuclear receptor constitutive activated/androstane receptor (CAR). In mouse livers, CAR, not PXR, was responsible for Cyp2b10 mRNA induction by BDE-47. In human primary hepatocytes, BDE-47 was able to induce translocation of YFP-tagged human CAR from the cytoplasm to the nucleus andCYP2B6 and CYP3A4 mRNAs expressions. BDE-47 activated human CAR in a manner akin to the human CAR ligand CITCO (6-(4-Chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde-O-(3,4-dichlorobenzyl)oxime) in luciferase-reporter assays using Huh-7 cells. In contrast, mouse CAR was not potently activated by BDE-47 in the same reporter assays. Furthermore, human pregnane X receptor (PXR) was effectively activated by BDE-47 while mouse PXR was weakly activated in luciferase-reporter assays. Our results indicate that BDE-47 induces CYP genes through activation of human CAR in addition to the previously identified pathway through human PXR. [ABSTRACT FROM AUTHOR]

Constituent chemicals in garlic extract are known to induce phase I and phase II enzymes in rodent livers. Here we have utilized Car+/+ and Car2/2 mice to demonstrate that the nuclear xenobiotic receptor CAR regulated the induction of the estrogen sulfotransferase Sult1e1 gene by diallyl sulfide (DAS) treatment in mouse liver. DAS treatment caused CAR accumulation in the nucleus, resulting in a remarkable increase of SULT1E1 mRNA (3,200 fold) and protein in the livers of Car+/+ females but not of Car2/2 female mice. DAS also induced other CAR-regulated genes such as Cyp2b10, Cyp3a11 and Gadd45b. Compared with the rapid increase of these mRNA levels, which began as early as 6 hourrs after DAS treatment, the levels of SULT1E1 mRNA began increasing after 24 hours. This slow response to DAS suggested that CAR required an additional factor to activate the Sult1e1 gene or that this activation was indirect. Despite the remarkable induction of SULT1E1, there was no decrease in the serum levels of endogenous E2 or increase of estrone sulfate while the clearance of exogenously administrated E2 was accelerated in DAS treated mice. [ABSTRACT FROM AUTHOR]

Upon activation by therapeutics, the nuclear xenobiotic/constitutive active/androstane receptor (CAR) regulates various liver functions ranging from drug metabolism and excretion to energy metabolism. CAR can also be a risk factor for developing liver diseases such as hepatocellular carcinoma. Here we have characterized the conserved threonine 38 of human CAR as the primary residue that regulates nuclear translocation and activation of CAR. Protein kinase C phosphorylates threonine 38 located on the a-helix spanning from residues 29-42 that constitutes a part of the first zinc finger and continues into the region between the zinc fingers. Molecular dynamics study has revealed that this phosphorylation may destabilize this helix, thereby inactivating CAR binding to DNA as well as sequestering it in the cytoplasm. We have found, in fact, that helix-stabilizing mutations reversed the effects of phosphorylation. Immunohistochemical study using an anti-phosphothreonine 38 peptide antibody has, in fact, demonstrated that the classic CAR activator phenobarbital dephosphorylates the corresponding threonine 48 of mouse CAR in the cytoplasm of mouse liver and translocates CAR into the nucleus. These results define CAR as a cell signal-regulated constitutive active nuclear receptor. These results also provide phosphorylation/dephosphorylation of the threonine as the primary drug target for CAR activation. [ABSTRACT FROM AUTHOR]

Abstract: Various drugs such as phenobarbital (PB) trigger translocation of constitutive active/adrostane receptor (CAR) from the cytoplasm into the nucleus of mouse liver cells without directly binding to the receptor. We have now characterized the guanine nucleotide exchange factor epithelial cell-transforming gene 2 (ECT2) as a PB-inducible factor as well as a cellular signal that represses PB-triggered nuclear translocation of CAR. When CFP-tagged ECT2 was co-expressed with YFP-tagged CAR in the liver of Car −/− mice, ECT2 repressed CAR nuclear translocation. Coexpression of various deletion mutants delineated this repressive activity to the tandem Dbl homology/pleckstrin homology domains of ECT2 and to their cytosolic expression. CAR directly bound to the PH domain. Thus, ECT2 may comprise a part of the PB response signal regulating the intracellular trafficking of CAR. [Copyright &y& Elsevier]

Describes a novel nuclear receptor response module from the CYP2B6 encoding region. Induction of CYP2B6 gene expression; Transcriptional activation of CYP2B genes by xenobiotics; Human primary hepatocyte cultures and transfection assays.

Phenobarbital (PB) increases hepatic drug/steroid-metabolic capability by coordinately activating transcription of the genes encoding various metabolizing enzymes. The nuclear receptor CAR was first implicated as a transcription factor that activates the cytochrome P450 Cyp2b10 gene. In response to PB, CAR forms a heterodimer with the retinoid X receptor (RXR), binds to a PB response element (typified by DR-4 motif), and activates transcription of the gene. In the CAR-null mouse, PB does not only induce the Cyp2b10 gene, but also induces genes encoding various metabolizing enzymes. Thus, CAR is a general nuclear receptor that is essential for PB induction of drug/steroid metabolizing enzymes. PB also induces amino levulinate synthase 1 (ALAS-1), the rate-limiting enzyme in heme biosynthesis, to increase heme supply. However, PB induction of the synthase occurs in CAR-null mice, suggesting that CAR does not coordinate the heme synthesis for the induction of drug/steroid metabolism. [Copyright &y& Elsevier]