factor-1 hif-1-mediated repression: Topics by WorldWideScience.org

Gene repression by minimal lac loops in vivo

Among the different extracellular virulence factors produced by Pseudomonas aeruginosa are exotoxin A (ETA) and the pyoverdine and pyochelin siderophores. Production of ETA...Full Text Available

2009-10-01

Regulatory circuit for responses of nitrogen catabolic gene expression to the GLN3 and DAL80 proteins and nitrogen catabolite repression in Saccharomyces cerevisiae.

The inflexibility of double-stranded DNA with respect to bending and twisting is well established in vitro. Understanding apparent DNA physical properties in vivo is...Full Text Available

2010-12-01

Gene Repressive Activity of RIP140 Through Direct Interaction with CDK8.

We demonstrate that expression of the UGA1, CAN1, GAP1, PUT1, PUT2, PUT4, and DAL4 genes is sensitive to nitrogen catabolite repression. The expression of all these genes, with the exception of UGA1...Full Text Available

1993-01-01

Ability of a solid state fermentation technique to significantly minimize catabolic repression of. alpha. -amylase production by Bacillus licheniformis M27

Receptor interacting protein 140 (RIP140) is a coregulator for numerous nuclear receptors and transcription factors and primarily exerts gene-repressive activities on various target genes. We previously identified a spectrum of posttranslational modifications on RIP140 that augment its property and biological activity. In T(3)-triggered biphasic regulation of cellular retinoic acid binding protein 1 (Crabp1) gene along the course of fibroblast-adipocyte differentiation, we found TRAP220(MED1) critical for T(3)-activated chromatin remodeling whereas RIP140 essential for T(3)-repressive chromatin remodeling of this gene promoter. In this current study, we aim to examine whether and how RIP140 replaces TRAP220(MED1) on the CrabpI promoter in differentiating adipocyte cultures. We find increasing recruitment of RIP140 to this promoter, with corresponding reduction in TRAP220(MED1) recruitment during the T(3)-repressive phase. ...

2011-08-25

Transcriptional repression and developmental functions of the atypical vertebrate GATA protein TRPS1

The production of {alpha}-amylase by Bacillus licheniformis M27 in submerged fermentation was completely inhibited due to catabolic repression in medium containing 1% glucose. In contrast, the enzyme production in a solid state fermentation system was 19,550 units/ml extract even when the medium contained 15% glucose. The peak in enzyme titre was, however, shifted from 48 to 72 h. The ability of the solid state fermentation system to significantly overcome catabolic repression was not known earlier and is probably conferred by various physico-chemical factors and culture conditions specific to the system. (orig.).

1991-08-01

The interplay of StyR and IHF regulates substrate-dependent induction and carbon catabolite repression of styrene catabolism genes in Pseudomonas fluorescens ST

Known vertebrate GATA proteins contain two zinc fingers and are required in development, whereas invertebrates express a class of essential proteins containing one GATA-type zinc finger. We isolated...Full Text Available

2001-04-02

The URE2 protein regulates nitrogen catabolic gene expression through the GATAA-containing UASNTR element in Saccharomyces cerevisiae.

BackgroundIn Pseudomonas fluorescens ST, the promoter of the styrene catabolic operon, PstyA, is induced by styrene and is subject to catabolite...Full Text Available

The Specificity of Innate Immune Responses Is Enforced by Repression of Interferon Response Elements by NF-?B p50

Many of the gene products that participate in nitrogen metabolism are sensitive to nitrogen catabolite repression (NCR), i.e., their expression is decreased to low levels when readily used nitrogen...Full Text Available

1994-12-01

TFIIH Operates through an Expanded Proximal Promoter To Fine-Tune c-myc Expression

The specific binding of transcription factors to cognate sequence elements is thought to be critical for the generation of specific gene expression programs. Members of the nuclear factor κB...Full Text Available

Staphylococcus aureus Aconitase Inactivation Unexpectedly Inhibits Post-Exponential-Phase Growth and Enhances Stationary-Phase Survival

A continuous stream of activating and repressing signals is processed by the transcription complex paused at the promoter of the c-myc proto-oncogene. The general transcription factor...Full Text Available

2005-01-01

Repressive BMP2 Gene Regulatory Elements Near the BMP2 promoter

Staphylococcus aureus preferentially catabolizes glucose, generating pyruvate, which is subsequently oxidized to acetate under aerobic growth conditions. Catabolite repression of the...Full Text Available

2002-11-01

The level of bone morphogenetic protein 2 (BMP2) profoundly influences essential cell behaviors such as proliferation, differentiation, apoptosis, and migration. The spatial and temporal pattern...Full Text Available

2010-02-05

Nitrogen metabolite repression of nitrate reductase in Neurospora crassa.

The activity of Src-related protein-tyrosine kinases is repressed by the phosphorylation of a conserved carboxyl-terminal tyrosine by another cytoplasmic protein-tyrosine kinase termed p50csk. In this...Full Text Available

1994-05-24

Catabolite Repression of the Citrate Fermentation Genes in Klebsiella pneumoniae: Evidence for Involvement of the Cyclic AMP Receptor Protein

The effect of different nitrogen compounds on the induction of reduced nicotinamide adenine dinucleotide phosphate-nitrate reductase was examined in Neurospora crassa. Whereas in the wild-type strain...Full Text Available

1979-03-01

Brg1 Is Required for Cdx2-Mediated Repression of Oct4 Expression in Mouse Blastocysts

Klebsiella pneumoniae is able to grow anaerobically with citrate as a sole carbon and energy source by a fermentative pathway involving the Na⁺-dependent citrate...Full Text Available

2001-09-01

A Response Regulator That Represses Transcription of Several Virulence Operons in the Group A Streptococcus

During blastocyst formation the segregation of the inner cell mass (ICM) and trophectoderm is governed by the mutually antagonistic effects of the transcription factors Oct4 and Cdx2. Evidence indicates...Full Text Available

Supplementation of pyruvate prevents palmitate-induced impairment of glucose uptake in C2 myotubes.

A search for homologs of the Bacillus subtilis PhoP response regulator in the group A streptococcus (GAS) genome revealed three good candidates. Inactivation of one of these, recently...Full Text Available

1999-06-01

Regulation of expression of a soybean storage protein subunit gene. Progress report

Elevated fatty acid levels have been thought to contribute to insulin resistance. Repression of the glucose transporter 4 (GLUT4) gene as well as impaired GLUT4 translocation may be a mediator for fatty acid-induced insulin resistance. This study was initiated to determine whether palmitate treatment repressed GLUT4 expression, whether glucose/fatty acid metabolism influenced palmitate-induced GLUT4 gene repression (PIGR), and whether attempts to prevent PIGR restored palmitate-induced impairment of glucose uptake (PIIGU) in C2 myotubes. Not only stimulators of fatty acid oxidation, such as bezafibrate, AICAR, and TOFA, but also TCA cycle substrates, such as pyruvate, leucine/glutamine, and ?-ketoisocaproate/monomethyl succinate, significantly prevented PIGR. In particular, supplementing with pyruvate through methyl pyruvate resulted in nearly complete prevention of PIIGU, whereas palmitate treatment reduced the ...

2011-07-23

Primary organization of nucleosomal core particles is invariable in repressed and active nuclei from animal, plant and yeast cells.

We have found that the methionine repression of the ..beta..-subunit gene expression is not due to degradation of the ..beta..-subunit but is due to an effect on synthesis of the ..beta..-subunit. The effect of methionine on the synthesis of the ..beta..-is due to an inhibition of ..beta..-subunit mRNA synthesis. 3 references, 1 figure.

1984-04-23

1 2 3 4

Forkhead Box Transcription Factor FOXO3a Regulates Estrogen Receptor Alpha Expression and Is Repressed by the Her-2/neu/Phosphatidylinositol 3-Kinase/Akt Signaling Pathway

A refined map for the linear arrangement of histones along DNA in nucleosomal core particles has been determined by DNA-protein crosslinking. On one strand of 145-bp core DNA, histones are aligned in...Full Text Available

1985-05-24

The selective hypoxia inducible factor-1 inhibitor PX-478 provides in vivo radiosensitization through tumor stromal effects

The expression status of the estrogen receptor alpha (ERα) and that of the epidermal growth factor receptor Her-2/neu frequently correlate inversely in breast cancers. While ERα-dependent...Full Text Available

2004-10-01

W. E. B. Du Bois's Basic American Negro Creed and the Associates in Negro Folk Education: A Case of Repressive Tolerance in the Censorship of Radical Black Discourse on Adult Education

Hypoxia inducible factor-1 (HIF-1) promotes tumor cell adaptation to microenvironmental stress. HIF-1 is up-regulated in irradiated tumors and serves as a promising target for radiosensitization....Full Text Available

2009-04-01

Induced Expression of Doublesex-and mab-3-related Transcription Factor-1 (DMRT-1) mRNA by Testosterone in the Olive Flounder, Paralichthys olivaceus ovary

W. E. B. Du Bois, one of the brightest lights in African American history, wrote a sparkling critique of the American social and economic system originally planned as part of the Bronze Booklets series, edited and published by Alain Locke and the Associates in Negro Folk Education. The piece was never published and has, until now, been lost to the annals of adult education history. Using historical evidence, the authors examine Du Bois's Basic American Negro Creed and the circumstances that led to its exclusion from the series. It is argued that the Creed was far too radical for the liberal minded Carnegie Corporation and its leaders who were only interested in accommodating adult education for Blacks through the AAAE funded Bronze Booklets. The exclusion of the Creed represents an example of repressive tolerance by the AAAE.

2008-12-01

KoreaScience (Korea)

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2007-08-01

Deficiency in trefoil factor 1 (TFF1) increases tumorigenicity of human breast cancer cells and mammary tumor development in TFF1-knockout mice

A heteromeric complex containing the centromere binding factor 1 and two basic leucine zipper factors, Met4 and Met28, mediates the transcription activation of yeast sulfur metabolism.

Although trefoil factor 1 (TFF1; previously named pS2) is abnormally expressed in about 50% of human breast tumors, its physiopathological role in this disease has been poorly studied. Moreover,...Full Text Available

2011-07-21

Inhibitory activity of Pseudomonas sp. on Flavobacterium psychrophilum, in vitro

Transcription activation of sulfur metabolism in yeast is dependent on two DNA binding factors, the centromere binding factor 1 (Cbf1) and Met4. While the role of Met4 was clearly established by showing...Full Text Available

1996-05-15

British Library Electronic Table of Contents (United Kingdom)

Abstract A Pseudomonas sp. isolate MSB1 efficiently inhibited the growth of Flavobacterium psychrophilum of different serotypes on agar medium. A significant difference in the inhibition was observed between isolates of the less virulent FpT serotype compared to the Fd and Th serotypes. In broth coculture experiments, a low number of cells of MSB1 inhibited and outcompeted the F.psychrophilum cells. Also cell-free culture supernatant of MSB1 clearly repressed the growth of F.psychrophilum. A chromoazurol S assay suggested that MSB1 produced efficient siderophores, which most probably were responsible for the iron deficiency in the supernatant. The limited growth of F.psychrophilum in the supernatant was found to be partly because of the lack of available iron, but the results also indicate...

2011-01-01

Effect of induction of SOS response on expression of pBR322 genes and on plasmid copy number

Translation Elongation Factor 1A Facilitates the Assembly of the Tombusvirus Replicase and Stimulates Minus-Strand Synthesis

Several lines of evidence are presented that indicate that the level of tetracycline resistance of Esherichia coli strains harboring plasmid pBR322 varies according to whether the SOS system of the host bacteria has been induced. These include use of strains in which the SOS system is expressed constitutively (lexA def.), is thermoinducible (recA441) or noninducible (lexA ind-), or is highly repressed (multiple copies of lexA+). Similar induction was observed with the product of another plasmid gene, beta-lactamase. The amounts of extractable plasmid DNA were also increased by SOS induction, and we propose that the SOS-induced increases in levels of tetracycline resistance and beta-lactamase activity are due to an increased plasmid copy number.

1989-09-01

Transforming growth factor-?1 induces intestinal myofibroblast differentiation and modulates their migration

Replication of plus-strand RNA viruses depends on host factors that are recruited into viral replicase complexes. Previous studies showed that eukaryotic translation elongation factor (eEF1A) is one...Full Text Available

2010-11-01

Stromal-Derived Factor-1 (CXCL12) Regulates Laminar Position of Cajal-Retzius Cells in Normal and Dysplastic Brains

AIM: To investigate the effects of transforming growth factor β1 (TGF-β1) on the differentiation of colonic lamina propria fibroblasts (CLPF) into myofibroblasts in vitro.METHODS:...Full Text Available

2009-03-28

SirT3 suppresses hypoxia inducible factor 1? and tumor growth by inhibiting mitochondrial ROS production

Normal brain development requires a series of highly complex and interrelated steps. This process presents many opportunities for errors to occur, which could result in developmental defects...Full Text Available

2006-09-13

Regulation of life span by mitochondrial respiration: the HIF-1 and ROS connection

It has become increasing clear that alterations in cellular metabolism have a key role in the generation and maintenance of cancer. Some of the metabolic changes can be attributed to the activation...Full Text Available

2011-06-30

Critical role of SDF-1?-induced progenitor cell recruitment and macrophage VEGF production in the experimental corneal neovascularization

A mild reduction in mitochondrial respiration extends the life span of many species, including C. elegans. We recently showed that hypoxia-inducible factor 1 (HIF-1) is required for...Full Text Available

Adenomatous Polyposis Coli and Hypoxia-inducible Factor-1? Have an Antagonistic Connection

PurposeTo address the roles of the stromal derived factor-1 (SDF-1) α in the course of experimental corneal neovascularization (CNV).MethodsCNV...Full Text Available

Transcription Factor IIA t Is Associated with Undifferentiated Cells and Its Gene Expression Is Repressed in Primary Neurons at the Chromatin Level In Vivo

The tumor suppressor adenomatous polyposis coli (APC) is mutated in the majority of colorectal cancers and is best known for its role as a scaffold in a Wnt-regulated protein complex that determines...Full Text Available

2010-11-01

British Library Electronic Table of Contents (United Kingdom)

The levels of General Transcription Factor (TF) IIA were examined during mammalian brain development and in rat embryo fibroblasts and transformed cell lines. The large TFIIA subunit paralogues ab and t are largely produced in unsynchronized cell lines, yet only TFIIA ab is observed in a number of differentiated tissue extracts. Steady-state protein levels of the TFIIA t, ab, and g subunits were significantly reduced when human embryonal (ec) and hepatic carcinoma cell lines were stimulated to differentiate with either all-trans-retinoic acid (ATRA) or sodium butyrate. ATRA-treated NT2-ec cells required replating to induce a neuronal phenotype and loss of detectable TFIIA t and g proteins. High levels of TFIIA t, ab, and g and Sp factors were identified in extracts from human fetal and rat...

2006-01-01

Regulatory role of neuron-restrictive silencing factor in expression of TRPC1

NADP Regulates the Yeast GAL Induction System

Neuron-restrictive silencer factor (NRSF) binds its consensus element to repress the transcription of various genes. The dominant-negative form (dnNRSF) has a hypertrophic effect on cardiogenesis through an unidentified mechanism. We examined the involvement of transient receptor potential (TRP) channel proteins, using transgenic mice overexpressing dnNRSF (dnNRSF mice). Electrophoretic mobility-shift assays revealed an interaction between NRSF and a neuron-restrictive silencer element-like sequence in intron 4 of TRPC1 genomic DNA. According to RT-PCR and Western analyses, TRPC1 was up-regulated in dnNRSF mouse heart. Transient overexpression of TRPC1 in HEK 293T cells increased the activity of the nuclear factor in activated T cells (NFAT) promoter and stimulated store-operated Ca"2"+ channel (SOCC)-mediated Ca"2"+ entry. Transfection of TRPC1 into primary cardiomyocytes increased NFAT activity, indicating a major role for TRPC1 in NFAT activation. Our findings ...

2006-12-22

Mutations in cyr1 and pat1 reveal pheromone-induced G1 arrest in the fission yeast Schizosaccharomyces pombe

Transcriptional regulation of the galactose-metabolizing genes in Saccharomyces cerevisiae depends on three core proteins: Gal4p, the transcriptional activator that binds to upstream activating DNA sequences (UASGAL); Gal80p, a repressor that binds to the carboxyl terminus of Gal4p and inhibits transcription; and Gal3p, a cytoplasmic transducer that, upon binding galactose and adenosine 5'-triphosphate, relieves Gal80p repression. The current model of induction relies on Gal3p sequestering Gal80p in the cytoplasm. However, the rapid induction of this system implies that there is a missing factor. Our structure of Gal80p in complex with a peptide from the carboxyl-terminal activation domain of Gal4p reveals the existence of a dinucleotide that mediates the interaction between the two. Biochemical and in vivo experiments suggests that nicotinamide adenine dinucleotide phosphate (NADP) plays a key role in the initial induction event.

2008-01-01

DEFF Research Database (Denmark)

Investigations into sexual differentiation and pheromone response in the fission yeast Schizosaccharomyces pombe are complicated by the need to first starve the cells of nitrogen. Most mating-related experiments are therefore performed on non-dividing cells. Here we overcome this problem by using two mutants that bypass the nutritional requirements and respond to the M-factor mating pheromone in rich medium. The first mutant lacks the cyr1 gene which encodes adenylate cyclase and these cells contain no measurable amounts of cAMP. When M-factor is added to a growing h+ cyr1- strain it causes a transient G1 arrest of cell division, transcription of mat1-Pm, and elongation of the cells to form shmoos. The second mutant contains the temperature-sensitive pat1-114 allele. At 30 degrees C this mutant was previously shown not only to bypass the nutritional signal but also to stop growing in a state derepressed for pheromone-controlled functions. We now report that an h+ pat1-114 strain ...

1994-01-01

1 2 3 4

NADPH oxidase-mediated reactive oxygen species production activates hypoxia-inducible factor-1 (HIF-1) via the ERK pathway after hyperthermia treatment

Mutations at the accommodation gate of the ribosome impair RF2-dependent translation termination

Hyperthermia (HT) is a strong adjuvant treatment with radiotherapy and chemotherapy because it causes tumor reoxygenation. However, the detailed molecular mechanisms of how HT enhances tumor oxygenation...Full Text Available

2010-11-23

Effects of Short-Term Treadmill Exercise Training or Growth Hormone Supplementation on Diastolic Function and Exercise Tolerance in Old Rats

During protein synthesis, aminoacyl-tRNA (aa-tRNA) and release factors 1 and 2 (RF1 and RF2) have to bind at the catalytic center of the ribosome on the 50S subunit where they take part in peptide bond...Full Text Available

2010-09-01

XRF analysis of rock and sediment using standard rock samples

Whether the lusitropic potential of short-term exercise in aged rats is linked to an augmentation in the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis and an alteration in the...Full Text Available

2008-09-01

XRF analysis of rock and sediment using standard rock samples

A simple and rapid method is described for the determination of major and trace elements in rock and sediment samples by wavelength dispersive XRF. Sample measured were made from cellulose powder pressed into 4 cm diameter aluminium ring 0.4 t cm/sup -2/, and then 1 g of powdered sample (0.08 g cm/sup -2/) was placed on the disk and repressed at 1.6 t cm/sup -2/. X-ray measurements were performed for total XRF intensity (I/sub p/) at the characteristic line of each element and background intensity (I/sub b/) in vicinity of the line. The correction of matrix effect was achieved by X-ray intensity ratio of peak to background for each element. Eight standard rock samples from Geological Survey of Japan were used as standard materials, and linear calibration curves were obtained by the plot of I/sub p/ - I/sub b/ vs. concentration for Ca, Na and Pb and by the plot of I/sub p//I/sub b/ ratio vs. concentration for Si, Fe, Ti, K, P, Cl, Cr, Mn, Ni, Cu, Zn, Pb, Sr and Ba, ...

1987-03-01

Transcription regulation of the vegf gene by the BMP/Smad pathway in the angioblast of zebrafish embryos

A simple and rapid method is described for the determination of major and trace elements in rock and sediment samples by wavelength dispersive XRF. Sample measured were made from cellulose powder pressed into 4 cm diameter aluminium ring 0.4 t cm"-"2, and then 1 g of powdered sample (0.08 g cm"-"2) was placed on the disk and repressed at 1.6 t cm"-"2. X-ray measurements were performed for total XRF intensity (I_p) at the characteristic line of each element and background intensity (I_b) in vicinity of the line. The correction of matrix effect was achieved by X-ray intensity ratio of peak to background for each element. Eight standard rock samples from Geological Survey of Japan were used as standard materials, and linear calibration curves were obtained by the plot of I_p - I_b vs. concentration for Ca, Na and Pb and by the plot of I_p/I_b ratio vs. concentration for Si, Fe, Ti, K, P, Cl, Cr, Mn, Ni, Cu, Zn, Pb, Sr and Ba, respectively. The relative standard ...

N"v"a"r"-"e"p"s"i"l"o"n-acetyl-#beta#-lysine: An osmolyte synthesized by mothanogenic archaebacteria

Vascular endothelial growth factor (VEGF) is a mitogen that is critically involved in vasculogenesis, angiogenesis, and hematopoiesis. However, what and how transcription factors participate in the regulation of vegf gene expression are not fully understood. Here we report the cloning and sequencing of the zebrafish vegf promoter which revealed that the promoter contains a number of bone morphogenetic protein (BMP)-activated Smad binding elements (SBE), implicating Smad1 and Smad5 in the regulation of BMP-induced expression of vegf. Electrophoretic mobility shift assays of adding recombinant Smad proteins to the SBE-containing DNA oligonucleotides that represent portions of zebrafish vegf promoter resulted in mobility shift of the oligonucleotides. These changes demonstrate potential interactions between Smad1/5 and the vegf promoter. Reporter activity assays using the wild-type or SBE-deleted vegf promoters to drive the luciferase reporter gene expression revealed that Smad1 ...

2005-04-01

Competitive degradation between the fumigants chloropicrin and 1,3-dichloropropene in unamended and amended soils.

Methanosarcina thermophila, a nonmarine methanogenic archaebacterium, can grow in a range of saline concentrations. At less than 0.4 M NaCl, Ms. thermophila accumulated glutamate in response to increasing osmotic stress. At greater than 0.4 M NaCl, this organism synthesized a modified #beta#-amino acid that was identified as N"v"a"r"-"e"p"s"i"l"o"n-acetyl-#beta#-lysine by NMR spectroscopy and ion-exchange HPLC. This #beta#-amino acid derivative accumulated to high intracellular concentrations (up to 0.6 M) in Ms. thermophila and in another methanogen examined - Methanogenium cariaci, a marine species. The compound has features that are characteristic of a compatible solute: it is neutrally charged at physiological pH and it is highly soluble. When the cells were grown in the presence of exogenous glycine betaine, a physiological pH and it is highly soluble. When the cells were grown in the presence of exogenous glycine betaine, a physiological compatible solute, ...

The relationships among bone health, insulin-like growth factor-1 and sex hormones in adolescent female athletes

The mixture of 1,3-dichloropropene (1,3-D) and chloropicrin (CP) is used as a preplant soil fumigant. In comparison with individual fumigants, application of a mixture may affect the environmental dissipation and fate of each chemical, such as emission and degradation. We investigated the degradation of CP, 1,3-D, and their mixture in fresh soils and sterile soils, and evaluated the competitive characteristic of fumigants in the mixture. The degradation of low concentrations of CP in fresh soil was accelerated at early times in the presence of 1,3-D, whereas the addition of CP reduced the degradation rate of trans-1,3-D, possibly by inhibiting the activity of trans-1,3-D degrading microorganisms. The potential of applying amendments to the soil to increase the rate of CP and 1,3-D degradation was also illustrated. The degradation of both fumigants was significantly enhanced in soils amended with ammonium thiosulfate (ATS) and sodium diethyldithiocarbamate (Na-DEDTC) compared with ...

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to determine the relationships of bone mineral density (BMD) and content (BMC) with insulin-like growth factor-1 (IGF-1), IGF-binding protein-3 (IGFBP-3) and estradiol in pubertal female athletes. The participants were 170 healthy adolescent girls (13?15?years) who participated in competitive extramural athletic programs, i.e., sports games (n?=?49), track sprinting (n?=?24), rhythmic gymnastics (n?=?23), swimming (n?=?24) and cross-country skiing (n?=?17). The control group (n?=?33) consisted of girls who took part only in compulsory physical education classes at school. The whole-body BMD and femoral neck and lumbar spine BMD and BMC were measured using DXA, and the volumetric BMD was calculated. Venous blood samples to determine the concentration of IGF-1, IGFB...

2010-01-01

Changes of hypoxia inducible factor-1 ? in hepatoma cells irradiated by gamma ray and their mechanism

Regulation of Redd1 Expression by Hypoxia

This paper reports regulation of hypoxia inducible factor-1 ? (HIF-1 ?)in hepatoma cells by irradiation. Cobalt chloride (CoCl2), a chemical mimic agent for hypoxia research, was utilized to induce the stable expression of HIF-1 ? in HepG2 cells. The HepG2 cells were irradiated to different doses to observe the changes of HIF-1 ?. The level of intracellular reactive oxygen species (ROS) was assayed by fluorescent microscope and flow cytometry (FCM). The results showed that there were obvious changes in expression of HIF-1 ? after HepG2 cells exposed to radiation, and the changes were positively related with the irradiation dose from 1 Gy to 5 Gy. Moreover, contents of incellular ROS were negatively correlated with above levels of HIF-1 ? from 1 Gy to 3 Gy. The results indicate that irradiation may enhance hypoxic cells HIF-1 ?, and the reduction of intracellular ROS can contribute to the regulation of ionizing radiation on HIF-1 ?. (authors)

2007-10-01

Displacement ventilation in industry - a design principle for improved air quality

Redd1, a recently discovered stress-response gene, is regulated by hypoxia via hypoxia-inducible factor 1 (HIF-1) and by DNA damage via p53/p63; however, the signaling pathway by which its expression is induced by hypoxia has not been elucidated. We demonstrated that the up-regulation of Redd1 transcription by hypoxia and high cell density (HCD) depends on cooperation between Sp1 and HIF-1#alpha# downstream of the PI3K/Akt pathway.

2006-05-25

Relationships between contraction properties of knee extensor muscles and fasting IGF-1 and adipocytokines in physically active postmenopausal women

There is very little quantitative documentation of actual improvements resulting from the installation of new general ventilation systems in industrial settings. Therefore the performance of the common mixing design principle was compared to the displacement design principle by means of an intervention study in a workshop (V = 12,000 m[sup 3]), where thermoplastics were moulded. An experimental signal-response tracer gas technique was used. In terms of supplying fresh air to the zone of occupancy the displacement system was better than the mixing system by a factor of 2. In terms of the exposure level to a simulated contaminant (tracer gas) the displacement system was better by a factor 1.5-18. (author)

1992-10-01

British Library Electronic Table of Contents (United Kingdom)

Summary The aim of this cross-sectional study was to find possible relationships between insulin-like growth factor-1 (IGF-1), adipocytokines (leptin and adiponectin) and twitch contraction (TC) characteristics of the knee extensor (KE) muscles in healthy physically active postmenopausal women (n = 28, 64-78 years old). We hypothesized that IGF-1 is related at least to isometric TC peak torque (Pt) as the highest value of isometric torque production and maximal voluntary contraction (MVC) torque, and there will not be any relationships between TC characteristics and leptin and adiponectin. During the measurement of MVC torque and twitch contractile properties of KE muscles, the subjects sat in a custom-made dynamometric chair with the knee and hip angles equal to 90degree and 100degree, re...

2010-01-01

Regional assessment of ambient volatile organic compounds from biopharmaceutical R&D complex

British Library Electronic Table of Contents (United Kingdom)

Biopharmaceutical R&D complexes are major emission sources of volatile organic compounds (VOCs), which may pose potential health risks for staff on site and residents nearby. In this paper health risk assessments were performed for the VOCs in the ambient air of a typical biopharmaceutical R&D complex in China. Results showed halogenated and alkyl compounds were dominant components among 24 major VOCs from 9 selected sampling sites, inside or around the complex. The principal component analysis (PCA) indicated VOCs were generated predominantly from the biopharmaceutical research activities (factor 1 (F1), 71.6%) and traffic vehicles (factor 2 (F2), 15.4%), which were confirmed by contour maps of five selected VOCs (benzene, toluene, chlorobenzene, methylene chloride and n-hexane) simulated...

2011-01-01

Study on the effectiveness of some decontamination agents against skin contamination of {sup 137}Cs and {sup 60}Co

Study on the effectiveness of some decontamination agents against skin contamination of "1"3"7Cs and "6"0Co

In order to evaluate the effectiveness of some decontamination agents against skin contamination of {sup 60}Co and {sup 137}Cs, the experiments were carried out in this study. In the experiments, pig skin was used instead of human skin, {sup 60}CoCl{sub 2} and {sup 137}CsCl were used the liquid sources of skin contamination. To examine the effectiveness of decontamination agents, skin decontamination was tried using soup, EDTA, DAERICON which was developed for decontamination of radionuclides on the surface of building structure, and new decontamination agents such as IOCON, TRICON, and CHARCON, which were developed in this study. The absorption of radionuclides through the skin was evaluated by the gamma-ray detection on the surface of sample skin after radionuclides were penetrated into the skin during 16 hour soiling time. The results of this absorption experiment indicated that 11.5% and 3.2% of initial amounts of {sup 137}Cs and {sup 60}Co, respectively, were penetrated into the ...

1998-03-01

Development and evaluation of a conditionally lethal transgenic pink bollworm

In order to evaluate the effectiveness of some decontamination agents against skin contamination of "6"0Co and "1"3"7Cs, the experiments were carried out in this study. In the experiments, pig skin was used instead of human skin, "6"0CoCl_2 and "1"3"7CsCl were used the liquid sources of skin contamination. To examine the effectiveness of decontamination agents, skin decontamination was tried using soup, EDTA, DAERICON which was developed for decontamination of radionuclides on the surface of building structure, and new decontamination agents such as IOCON, TRICON, and CHARCON, which were developed in this study. The absorption of radionuclides through the skin was evaluated by the gamma-ray detection on the surface of sample skin after radionuclides were penetrated into the skin during 16 hour soiling time. The results of this absorption experiment indicated that 11.5% and 3.2% of initial amounts of "1"3"7Cs and "6"0Co, respectively, were penetrated into the skin. In the experiment to ...

1998-03-01

Ultrashort echo time MRI of cortical bone at 7 tesla field strength: A feasibility study

A new area-wide pest control strategy using the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), genetically transformed with a conditionally lethal gene, is under development. Conditional lethality of several transgenic pink bollworm strains was demonstrated in a series of laboratory rearing experiments. Pink bollworms were transformed with genetic constructs using the RIDL technology (Release of Insects with a Dominant Lethal gene) for development of an autocidal biological control system for possible supplement or replacement of radiation based sterile insect release. LA1124 is a lethal construct controlled by a tetracycline repressible transactivator protein (tTA), in which binding of tTA to its specific target sequence tetO drives production of more tTA. In the absence of tetracycline, this leads to lethality by high expression of tTA. When tetracycline is present, tTA does not bind tetO, and so the positive feedback cycle is not ...

2005-05-09

British Library Electronic Table of Contents (United Kingdom)

AbstractPurpose: To implement and examine the feasibility of a three-dimensional (3D) ultrashort TE (UTE) sequence on a 7 Tesla (T) clinical MR scanner in comparison with 3T MRI at high isotropic resolution. Materials and Methods: Using an in-house built saddle coil at both field strengths we have imaged mid-diaphysial sections of five fresh cadaveric specimens of the distal tibia. An additional in vivo scan was performed at 7 Tesla using a quadrature knee coil. Results: Using the same type of saddle coil at both field strengths, a significant increase in SNR at 7T compared with 3T (factor 1.7) was found. Significantly shorter T2* values were found at the higher field strength (T2* = 552.2 126 s at 7T versus T2* = 1163 391 s at 3T). Conclusion: UHF MRI at 7T has great potential for imaging...

2011-01-01

Study of Bs-> \\phi l^+ l^-$ Decay in a Single Universal Extra Dimension

CERN Document Server

Utilizing form factors calculated within the light-cone sum rules, we have evaluated the decay branching ratios of $B_s\\to \\phi\\gamma$ and $B_s\\to \\phi \\ell^+\\ell^-$ in a single universal extra dimension model (UED), which is viewed as one of the alternative theories beyond the standard model (SM). For the decay $B_s \\to \\phi \\ell^+\\ell^-$, the dilepton invariant mass spectra, the forward-backward asymmetry, and double lepton polarization are also calculated. For each case, we compared the obtained results with predictions of the SM. In lower values of the compactification factor 1/R, the only parameter in this model, we see the considerable discrepancy between the UED and SM models. However, when 1/R increases, the results of UED tend to diminish and at $1/R = 1000 \\mathrm{GeV}$, two models have approximately the same predictions. Compared with data from CDF of $B_s \\to \\phi \\mu^+ \\mu^-$, the 1/R tends to be larger than $350 ...

2011-01-01

Modified 9Cr-1Mo steel shows excellent potential for steam generator applications

HSP70, the earliest-induced gene in the zebrafish retina during optic nerve regeneration: Its role in cell survival

A 9Cr-1Mo steel with properties improved over other ferritics in the ranges from 9 to 12% Cr and 1 to 2% Mo and over the widely used 2 1/2 Cr-1Mo steel has recently been developed. The main changes in the modified alloy, compared with the standard alloy, include: addition of niobium and vanadium, to improve the alloy's elevated-temperature strength properties; a specified range for each element; and a specification for nitrogen, which is not listed for the standard 9Cr-1Mo. Microstructural work has indicated that the improved strength of the modified alloy comes from two factors: (1) fine M/sub 23/C/sub 6/ precipitate particles nucleate on Nb/C, N, which comes out first during the heat treatment; and (2) the vanadium enters M/sub 23/C/sub 6/ and retards its growth at the service temperature. Mechanical properties discussed were Charpy-impact, tensile, and creep properties. Other properties included were: thermal expansion coefficient, ...

1982-12-01

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British Library Electronic Table of Contents (United Kingdom)

Fish retinal ganglion cells (RGCs) can survive and regrow their axons after optic nerve injury. Injured RGCs express anti-apoptotic proteins, such as Bcl-2, after nerve injury; however, upstream effectors of this anti-apoptotic protein are not yet fully understood. Heat shock proteins (HSPs) play a crucial role in cell survival against various stress conditions. In this study, we focused on HSP70 expression in the zebrafish retina after optic nerve injury. HSP70 mRNA and protein levels increased rapidly 2.3-fold in RGCs by 1-6 h after injury and returned to control levels by 1-3 days. HSP70 transcription is regulated by heat shock factor 1 (HSF1). HSF1 mRNA and phosphorylated-HSF1 protein rapidly increased by 2.2-fold in RGCs 0.5-6 h after injury. Intraocular injection of HSP inhibitor I s...

2011-01-01

Gap-junctional communication of bone marrow stromal cells is resistant to irradiation in vitro

Gap-junctional communication of bone marrow stromal cells is resistant to irradiation in vitro

Bone marrow is one of the most radiosensitive organs. Irradiation causes a marked decrease in the total number of hematopoietic cells in the bone marrow. The reticular meshwork structure of marrow stromal cells, however, is relatively resistant to irradiation. Unimpaired stromal cell structure has been thought to be a prerequisite for the repopulation of hematopoietic cells during recovery from the effects of irradiation. The reticular framework is maintained by cell adhesion apparatuses such as gap junctions. The in vitro radiobiologic survival values of a cloned stromal cell line, H-1/A, were studied (n = 1.8, D0 = 138 cGy). Radiation doses of up to 4000 cGy had no detectable effects on the production of colony-stimulating factor 1. H-1/A cells communicate with each other via gap junctions as determined by the sensitive dye-transfer method. Gap-junctional communication between H-1/A cells was resistant to different levels of irradiation (500 ...

1990-10-01

Electron spin resonance investigation of Mn^{2+} ions and their dynamics in manganese doped SrTiO_3

CERN Document Server

Using electron spin resonance, lattice position and dynamic properties of Mn2+ ions were studied in 0.5 and 2 % manganese doped SrTiO3 ceramics prepared by conventional mixed oxide method. The measurements showed that Mn2+ ions substitute preferably up to 97 % for Sr if the ceramics is prepared with a deficit of Sr ions. Motional narrowing of the Mn2+ ESR spectrum was observed when temperature increases from 120 K to 240-250 K that was explained as a manifestation of off-center position of this ion at the Sr site. From the analysis of the ESR spectra the activation energy Ea = 86 mV and frequency factor 1/?0 ? (2-10)x10^(-14) 1/s for jumping of the impurity between symmetrical off-center positions were determined. Both values are in agreement with those derived previously from dielectric relaxation. This proves the origin of dielectric anomalies in SrTiO3:Mn as those produced by the reorientation dynamics of Mn2+ dipoles.

2007-01-01

Angiogenic cytokines and growth factors in systemic sclerosis.

A DC-81-indole conjugate agent suppresses melanoma A375 cell migration partially via interrupting VEGF production and stromal cell-derived factor-1a-mediated signaling

Systemic sclerosis is an autoimmune connective tissue disorder characterized by a widespread microangiopathy, autoimmunity and fibrosis of the skin and of various internal organs. Microangiopathy is characterized by a reduced capillary density and an irregular chaotic architecture that lead to chronic tissue hypoxia. Despite the hypoxic conditions, there is no evidence for a sufficient compensative angiogenesis in SSc. Furthermore, vasculogenesis is also impaired. An imbalance between angiogenic and angiostatic factors might explain the pathogenetic mechanisms of SSc vasculopathy. As far as angiogenic factors are concerned, within the most important are vascular endothelial growth factor (VEGF) and its receptors, platelet derived growth factor (PDGF), transforming growth factor beta (TGF-?), fibroblast growth factor -2 (FGF-2), angiopoietin 1 (Ang-1), stromal cell-derived factor 1 (SDF-1/CXCL12), endothelin-1 (ET-1), monocyte chemoattractant ...

2011-04-28

British Library Electronic Table of Contents (United Kingdom)

Pyrrolo[2,1-c][1,4]benzodiazepine (PBD) chemicals are antitumor antibiotics inhibiting nucleic acid synthesis. An indole carboxylate-PBD hybrid with six-carbon spacer structure (IN6CPBD) has been previously demonstrated to induce melanoma cell apoptosis and reduce metastasis in mouse lungs. This study aimed at investigating the efficacy of the other hybrid compound with four-carbon spacer (IN4CPBD) and elucidating its anti-metastatic mechanism. Human melanoma A375 cells with IN4CPBD treatment underwent cytotoxicity and apoptosis-associated assays. Transwell migration assay, Western blotting, and ELISA were used for mechanistic study. IN4CPBD exhibited potent melanoma cytotoxicity through interrupting G1/S cell cycle progression, increasing DNA fragmentation and hypodipoidic DNA contents, a...

2011-01-01

Structural Insights into the Interaction of the Evolutionarily Conserved ZPR1 Domain Tandem with Eukaryotic EF1A, Receptors, and SMN Complexes

Regulation of lipoprotein lipase in primary cultures of isolated human adipocytes

Eukaryotic genomes encode a zinc finger protein (ZPR1) with tandem ZPR1 domains. In response to growth stimuli, ZPR1 assembles into complexes with eukaryotic translation elongation factor 1A (eEF1A) and the survival motor neurons protein. To gain insight into the structural mechanisms underlying the essential function of ZPR1 in diverse organisms, we determined the crystal structure of a ZPR1 domain tandem and characterized the interaction with eEF1A. The ZPR1 domain consists of an elongation initiation factor 2-like zinc finger and a double-stranded {beta} helix with a helical hairpin insertion. ZPR1 binds preferentially to GDP-bound eEF1A but does not directly influence the kinetics of nucleotide exchange or GTP hydrolysis. However, ZPR1 efficiently displaces the exchange factor eEF1B from preformed nucleotide-free complexes, suggesting that it may function as a negative regulator of eEF1A activation. Structure-based mutational and ...

2007-01-01

Potent, selective and cell penetrant inhibitors of SF-1 by functional ultra-high-throughput screening.

To study the regulation of adipose tissue lipoprotein lipase (LPL) in human adipocytes, omental adipose tissue was obtained from healthy subjects and digested in collagenase. The isolated adipocytes thus obtained were suspended in Medium 199 and cultured at 37 degrees C. Cell viability was demonstrated in adipocytes cultured for up to 72 h by constancy of cell number, cell size, trypan-blue exclusion, and specific /sup 125/I-insulin binding. In addition, chloroquine induced an increase in cell-associated /sup 125/I-insulin at 24, 48, and 72 h after preparation. Thus, isolated adipocytes retained their ability to bind, internalize, and degrade insulin. LPL was measured as activity secreted into the culture medium (CM), released from cells by heparin (HR), and extracted from cell digests. A broad range of heparin concentrations produced a prompt release of LPL from a rapidly replenishable pool of cellular activity. When cells were cultured in medium containing 10% fetal bovine serum, ...

1985-01-01

Olfactomedin 4 suppresses prostate cancer cell growth and metastasis via negative interaction with cathepsin D and SDF-1.

The steroidogenic factor 1 (SF-1, also known as NR5A1) is a transcription factor belonging to the nuclear receptor superfamily. Whereas most of the members of this family have been extensively characterized, the therapeutic potential and pharmacology of SF-1 still remains elusive. Described here is the identification and characterization of selective inhibitory chemical probes of SF-1 by a rational ultra-high-throughput screening (uHTS) strategy. A set of 64,908 compounds from the National Institute of Health's Molecular Libraries Small Molecule Repository was screened in a transactivation cell-based assay employing a chimeric SF-1 construct. Two analogous isoquinolinones, ethyl 2-[2-[2-(2,3-dihydro-1,4-benzodioxin-7-ylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate (SID7969543) and ethyl 2-[2-[2-(1,3-benzodioxol-5-ylmethylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate and (SID7970631), were identified as potent submicromolar ...

2008-03-11

Inhibitory effect of transforming growth factor-. beta. (TGF-. beta. ) on insulin-like growth factor 1 (IGF-1)-induced proliferation and differentiation in primary cultures of pig preadipocytes

The human olfactomedin 4 gene (OLFM4) encodes an olfactomedin-related glycoprotein. OLFM4 is normally expressed in a limited number of tissues, including the prostate, but its biological functions in prostate are largely unknown. In this study, we found that OLFM4 messenger RNA was reduced or undetectable in prostate cancer tissues and prostate cancer cell lines. To study the effects of OLFM4 on prostate cancer progression, we transfected PC-3 prostate cancer cells with OLFM4 to establish OLFM4-expressing PC-3 cell clones. The OLFM4-expressing PC-3 cell clones were found to have decreased proliferation and invasiveness compared with vector-transfected control PC-3 cells in vitro. In addition, nude mice injected with OLFM4-expressing PC-3 cells demonstrated reduced tumor growth and bone invasion and metastasis compared with mice injected with vector-transfected control cells. Mechanistic studies revealed that OLFM4 may exhibit its anticancer effects through regulating cell autophagy by ...

2011-04-05

Inhibitory effect of transforming growth factor-#beta# (TGF-#beta#) on insulin-like growth factor 1 (IGF-1)-induced proliferation and differentiation in primary cultures of pig preadipocytes

The influence of serum, IGF-1 and TGF-{beta} on the differentiation of preadipocytes was examined in primary cultures of porcine adipose tissue cells. In serum-supplemented or serum-free, IGF-1 (1 and 10 nM) had no effect on total cell number. However, IGF-1 (10nM) increased adipocyte number only in serum-supplemented (1% pig serum) cultures, whereas TGF-{beta} (15 pm) reduced the adipocyte number in the presence and absence of IGF-1. Replication of preadipocytes was analyzed with a ({sup 3}H) thymidine assay. Preadipocyte proliferation (cpm in adipocyte fraction) was increased by IGF-1 (10nM) only in cultures containing pig serum. TGF-{beta} had no effect on preadipocyte proliferation specifically, but slightly increased total ({sup 3}H) thymidine incorporation in cultures with serum. Glycerol phosphate dehydrogenase (GPDH) specific activity was decreased by adding TGF-{beta} to serum-free cultures but TGF-{beta} had little effect in serum-supplemented cultures. Cellular secretion of ...

1990-02-26

Beta-delayed proton emission: a new series of precursors, and the measurement of 10"-"1"6 s nuclear lifetimes

The influence of serum, IGF-1 and TGF-#beta# on the differentiation of preadipocytes was examined in primary cultures of porcine adipose tissue cells. In serum-supplemented or serum-free, IGF-1 (1 and 10 nM) had no effect on total cell number. However, IGF-1 (10nM) increased adipocyte number only in serum-supplemented (1% pig serum) cultures, whereas TGF-#beta# (15 pm) reduced the adipocyte number in the presence and absence of IGF-1. Replication of preadipocytes was analyzed with a ["3H] thymidine assay. Preadipocyte proliferation (cpm in adipocyte fraction) was increased by IGF-1 (10nM) only in cultures containing pig serum. TGF-#beta# had no effect on preadipocyte proliferation specifically, but slightly increased total ["3H] thymidine incorporation in cultures with serum. Glycerol phosphate dehydrogenase (GPDH) specific activity was decreased by adding TGF-#beta# to serum-free cultures but TGF-#beta# had little effect in serum-supplemented cultures. Cellular secretion of IGF-1 was ...

1991-04-21