WorldWideScience
1

Nitrogen-15-labeled deoxynucleosides. 3. Synthesis of (3- sup 15 N)-2 prime -deoxyadenosine  

Energy Technology Data Exchange (ETDEWEB)

The synthesis of (3-{sup 15}N)-labeled adenine has been reported by several groups. Each of these syntheses followed essentially the same route, in which the {sup 15}N is introduced by nitration of 4-bromoimidazole under forcing conditions using ({sup 15}N)-HNO{sub 3}. The authors have devised an alternate route which uses an azo coupling reaction for introduction of the {sup 15}N and proceeds through the intermediacy of (5-{sup 15}N)-labeled 5-aminoimidazole-4-carboxamide (AICA). An unrelated route to the (5-{sup 15}N)-labeled 5-amino-imidazole ribonucleoside (AIRs) was recently reported. AICA is a versatile precursor, which is most commonly used for entry into the guanine or isoguanine families, although it is usually used as the AICA-riboside rather than the heterocycle itself. The authors have found that AICA also can be used for the adenine family by ...

1990-10-24

2

Uniform and Residue-specific {sup 15}N-labeling of Proteins on a Highly Deuterated Background  

Energy Technology Data Exchange (ETDEWEB)

A general method for stable-isotope labeling of large proteins is introduced and applied for studies of the E. coli GroE chaperone proteins by solution NMR. In addition to enabling the residue-specific {sup 15}N-labeling of proteins on a highly deuterated background, it is also an efficient approach for uniform labeling. The method meets the requirements of high-level deuteration, minimal cross-labeling and high protein yield, which are crucial for NMR studies of structures with sizes above 150 kDa. The results obtained with the new protocol are compared to other strategies for protein labeling, and evaluated with regard to the influence of external factors on the resulting isotope labeling patterns. Applications with the GroE system show that these strategies are efficient tools for studies of structure, dynamics and intermolecular interactions in large supramolecular complexes, when combined with TROSY- and CRINEPT-based experimental NMR ...

2004-07-15

3

Clostridiaceae and Enterobacteriaceae as active fermenters in earthworm gut content  

British Library Electronic Table of Contents (United Kingdom)

The earthworm gut provides ideal in situ conditions for ingested heterotrophic soil bacteria capable of anaerobiosis. High amounts of mucus- and plant-derived saccharides such as glucose are abundant in the earthworm alimentary canal, and high concentrations of molecular hydrogen (H2) and organic acids in the alimentary canal are indicative of ongoing fermentations. Thus, the central objective of this study was to resolve potential links between fermentations and active fermenters in gut content of the anecic earthworm Lumbricus terrestris by 16S ribosomal RNA (rRNA)-based stable isotope probing, with [13C]glucose as a model substrate. Glucose consumption in anoxic gut content microcosms was rapid and yielded soluble organic compounds (acetate, butyrate, formate, lactate, propionate, succi...

2011-01-01

4

Interactions of myristic acid with bovine serum albumin: a 13C NMR study.  

UK PubMed Central (United Kingdom)

Interactions of myristic acid with bovine serum albumin were studied by 13C NMR spectroscopy at 50.3 MHz using 90% isotopically substituted [1-13C]-, [3-13C]-, and [14-13C]myristic acids, either individually...Full Text Available

1984-06-01

5

Bioavailability of nitrogen from sewage sludge using "1"5N-labelled ammonium sulphate  

International Nuclear Information System (INIS)

The high nutrient nitrogen and organic matter contents of sewage sludge (SS) make it a potential organic fertilizer for sandy soil. In this study, "1"5N-labelled ammonium sulphate was used to investigate the availability of nitrogen from irradiated and non-irradiated sewage sludge to tomato plants. The application of sewage sludge to sandy soil increased dry matter production (DMP), nitrogen yield (NY) and nitrogen recovery (NR) over two successive years. A positive relationship was found between sludge application rate and DMP and NY. The increase was significantly higher (P=0.05) in irradiated than non-irradiated sewage sludge. Total nitrogen derived from non-irradiated sewage sludge are : 48.0, 63.7, 73.5, 105.2 Kg/ha, whereas, the total nitrogen derived from irradiated sewage sludge are: 55.1, 72.5, 88.9, 141.4 Kg/ha corresponding to application rates of 10 t/ha, 20 t/ha, 30 t/ha, respectively. This was attributed to higher dry matter production in the later than the former. A ...

2001-01-01

7

Nitrogen Requirements and Balance of Protected Cucumber in Coastal Lebanon  

International Nuclear Information System (INIS)

Protected cultures are widespread along the Lebanese narrow coastline, encouraged by mild winter conditions. Although one of the most intensive production systems, water and nutrients managements are mostly empirical, based on the experience of the grower himself or of his workers. So far, water has been available in Lebanon, but it will become scarce within ten years. The conservation of water quality by a rational addition of nutrients is particularly relevant to protected cultures. This is important as greenhouses are developed on imported shallow soils that could be fragile and highly vulnerable to pollution. Sound management includes the amount and the forms of fertilizers as well as the modality of fertigation. An experiment was conducted during two spring seasons in a location along the northern coast in a typical unheated greenhouse. The cucumber response to two frequencies and modalities of fertigation was followed: continuous T2C and T3C and discontinuous T2D and T3D every ...

2003-10-01

8

Scintillation proximity assay for measurement of RNA methylation  

UK PubMed Central (United Kingdom)

Methylation of RNA by methyltransferases is a phylogenetically ubiquitous post-transcriptional modification that occurs most extensively in transfer RNA (tRNA) and ribosomal RNA (rRNA). Biochemical...Full Text Available

2009-03-01

12

Theoretical determination of 1H e 13C shielding constants of thymol  

International Nuclear Information System (INIS)

Portuguese 2004 2 p. Brazil Resende, Jarbas Magalhaes Vieira, Gessy

2004-07-27

14

Fatty acid distribution in systems modeling the normal and diabetic human circulation. A 13C nuclear magnetic resonance study.  

UK PubMed Central (United Kingdom)

A nonperturbing 13C nuclear magnetic resonance (NMR) method was used to monitor the equilibrium distribution of carboxyl 13C-enriched fatty acids (FA) between distinct binding sites on human serum albumin,...Full Text Available

1991-04-01

15

Quantitative evaluation of siRNA delivery in vivo  

UK PubMed Central (United Kingdom)

Effective small interfering RNA (siRNA)–mediated therapeutics require the siRNA to be delivered into the cellular RNA-induced silencing complex (RISC). Quantitative information of this essential...Full Text Available

2010-12-01

16

Genetic analysis of carbon isotope discrimination and its relation to yield in a wheat doubled haploid population.  

Science.gov (United States)

Carbon isotope discrimination (?(13) C) is considered a useful indicator for indirect selection of grain yield (GY) in cereals. Therefore, it is important to evaluate the genetic variation in ?(13) C and its relationship with GY. A doubled haploid (DH) population derived from a cross of two common wheat varieties, Hanxuan 10 (H10) and Lumai 14 (L14), was phenotyped for ?(13) C in the flag leaf, GY and yield associated traits in two trials contrasted by water availability, specifically, rain-fed and irrigated. Quantitative trait loci (QTLs) were identified by single locus and two locus QTL analyses. QTLs for ?(13) C were located on chromosomes 1A, 2B, 3B, 5A, 7A and 7B, and QTLs for other traits on all chromosomes except 1A, 4D, 5A, 5B and 6D. The population selected for high ?(13) ...

2011-09-01

17

Use of carbon stable isotope to investigate chloromethane formation in the electrolytic dechlorination of trichloroethylene  

International Nuclear Information System (INIS)

Carbon stable isotope trichloroethylene ("1"3C TCE) was used to investigate the formation of chloromethane (CM) during the electrolytic dechlorination of trichloroethylene (TCE) at a granular-graphite packed cathode. A method was developed to use a conventional GC/MS to analyze and quantify regular and "1"3C TCE and their dechlorination products. The concentration of a "1"3C compound can be calculated, based on the concentration of its regular counterpart, from the response ratio of two fragments of different mass per charge values from the compounds in a sample and two characteristic MS spectrum ratios: one is the response ratio of the two fragments of the regular compound, and the other is the response ratio of the corresponding fragments of the regular and "1"3C compounds at the same concentrations. The method was used to analyze the regular and "1"3C compounds observed in an experiment of dechlorination in an ammonium acetate solution that contained both regular TCE and "1"3C TCE. ...

2007-03-22

23

Bunyamwera virus can repair both insertions and deletions during RNA replication  

UK PubMed Central (United Kingdom)

The genomic termini of RNA viruses contain essential cis-acting signals for such diverse functions as packaging, genome translation, mRNA transcription, and RNA replication, and thus...Full Text Available

2010-06-01

24

/sup 18/O isotope effect in carbon-13 nuclear magnetic resonance spectroscopy. Part 8. Oxygen exchange of 2,4,6-trimethylpyrylium cation  

Energy Technology Data Exchange (ETDEWEB)

The rate of the oxygen-exchange reaction in an aqueous solution of a heterocyclic oxygen compound, 2,4,6-trimethylpyrylium perchlorate, was quantitated. The /sup 18/O isotope effect in /sup 13/C NMR spectroscopy affords a direct, continuous, and relatively simple analysis of the reaction and was used to obtain data on the incorporation of /sup 18/O from solvent H/sub 2//sup 18/O into the pyrylium salt. Due to the low solubility of this salt in aqueous solutions, 2,4,6-trimethyl(2-/sup 13/C)pyrylium perchlorate and 2,4,6-trimethyl(2,6-/sup 13/C/sub 2/)pyrylium perchlorate were synthesized to facilitate the acquisition of the data on an NTC-200 spectrometer operating at 50.31 MHz. Upon incorporation of /sup 18/O into the pyrylium salt, the /sup 13/C NMR signal of the directly bonded carbon atom is shifted upfield 0.038 ...

1984-12-12

25

Medium-chain fatty acid binding to albumin and transfer to phospholipid bilayers.  

UK PubMed Central (United Kingdom)

Temperature-dependent (5-42 degrees C) 13C NMR spectra of albumin complexes with 90% isotopically substituted [1-13C]decanoic acids (3 mol of fatty acid per mol of albumin) showed a single peak at greater...Full Text Available

1989-04-01

26

Temporal variations of the CO{sub 2} concentration and its carbon and oxygen isotopic ratios in a temperate forest in the central part of the main island of Japan  

Energy Technology Data Exchange (ETDEWEB)

Using discrete air sampling, values of {delta}{sup 13}C and {delta}{sup 18}O in atmospheric CO{sub 2}, as well as its concentration, were measured in a forest in the central part of the main island of Japan during the period from June 1994 to June 1996 to examine the biospheric contribution to their temporal variations. {delta}{sup 13}C shows a prominent diurnal variation with high values in the daytime and low values in the nighttime, especially during the warm season. {delta}{sup 13}C also vary seasonally, showing a maximum in summer and a minimum in spring. The diurnal and seasonal variations of {delta}{sup 13}C are opposite in phase with those of the CO{sub 2} concentration. The rate of change in {delta}{sup 13}C with respect to the CO{sub 2} concentration is found to be ...

1997-09-01

27

Enzyme induction in neonates after fetal exposure to antiepileptic drugs  

Energy Technology Data Exchange (ETDEWEB)

The /sup 13/C-AP breath test is shown to be a convenient, noninvasive method to monitor velocity and capacity of P450-dependent AP N-demethylation in infancy and childhood. According to /sup 13/C-AP breath tests, neonates have a very low capacity to eliminate /sup 13/CO/sub 2/, which is only 15 to 21% of the activity in adults. During the first year of life AP N-demethylation increases to reach its maximum at about 2 years; afterwards a slight decrease occurs. In 25 neonates exposed prenatally to different antiepileptic drugs /sup 13/C-AP breath test was efficiently used to prove that cytochrome AP N-demethylation was considerably stimulated. After primidone/phenobarbitone, especially in combination with phenytoin, /sup 13/C elimination reaches and even surpasses the range for older children. Valproate exposure during ...

1983-01-01

28

Hepatitis C Virus RNA Replication Requires a Conserved Structural Motif within the Transmembrane Domain of the NS5B RNA-Dependent RNA Polymerase ?  

UK PubMed Central (United Kingdom)

Hepatitis C virus (HCV) nonstructural protein 5B (NS5B), the viral RNA-dependent RNA polymerase (RdRp), is a tail-anchored protein with a highly conserved C-terminal transmembrane domain (TMD) that...Full Text Available

2010-11-01

29

A tRNA-like structure is present in 10Sa RNA, a small stable RNA from Escherichia coli.  

UK PubMed Central (United Kingdom)

We have determined that 10Sa RNA (one of the small stable RNAs found in Escherichia coli) has an interesting structural feature: the 5' end and the 3' end of 10Sa RNA can be arranged in a structure...Full Text Available

1994-09-27

30

The crystal structure of unmodified tRNAPhe from Escherichia coli  

UK PubMed Central (United Kingdom)

Post-transcriptional nucleoside modifications fine-tune the biophysical and biochemical properties of transfer RNA (tRNA) so that it is optimized for participation in cellular processes. Here we report...Full Text Available

2010-07-01

31

The DEXD/H-box RNA Helicase DDX19 Is Regulated by an ?-Helical Switch*S?  

UK PubMed Central (United Kingdom)

DEXD/H-box RNA helicases couple ATP hydrolysis to RNA remodeling by an unknown mechanism. We used x-ray crystallography and biochemical analysis of the human DEXD/H-box...Full Text Available

2009-04-17

32

Specific Residues of the Influenza A Virus Hemagglutinin Viral RNA Are Important for Efficient Packaging into Budding Virions?  

UK PubMed Central (United Kingdom)

A final step in the influenza virus replication cycle is the assembly of the viral structural proteins and the packaging of the eight segments of viral RNA (vRNA) into a fully infectious virion. The...Full Text Available

2007-09-01

33

Purification and translation of murine mammary tumor virus mRNA's.  

UK PubMed Central (United Kingdom)

We have studied the functions of the intracellular RNAs of mouse mammary tumor virus (MMTV) by purification and translation in vitro. Two major size classes of MMTV RNA, 35S and 24S RNA, were isolated...Full Text Available

1981-07-01

34

Nucleocapsid and Matrix Protein Contributions to Selective Human Immunodeficiency Virus Type 1 Genomic RNA Packaging  

UK PubMed Central (United Kingdom)

The nucleocapsid protein (NC) of retroviruses plays a major role in genomic RNA packaging, and some evidence has implicated the matrix protein (MA) of certain retroviruses in viral RNA binding. To further...Full Text Available

1998-03-01

35

Naturally occurring double-stranded RNA and immune responses. III. Immunogenicity and antigenicity in animals.  

UK PubMed Central (United Kingdom)

Naturally occurring, double-stranded RNA (ds-RNA)) was immunogenic when injected into mice, rats, guinea-pigs, rabbits, dogs and baboons. The response to native material administered intravenously (i.v.)...Full Text Available

1975-12-01

36

Mutational Analysis of cis-Acting RNA Signals in Segment 7 of Influenza A Virus?  

UK PubMed Central (United Kingdom)

The genomic viral RNA (vRNA) segments of influenza A virus contain specific packaging signals at their termini that overlap the coding regions. To further characterize cis-acting signals...Full Text Available

2008-12-01

37

Isoform-level microRNA-155 target prediction using RNA-seq  

UK PubMed Central (United Kingdom)

Computational prediction of microRNA targets remains a challenging problem. The existing rule-based, data-driven and expression profiling approaches to target prediction are mostly approached from the...Full Text Available

2011-05-01

38

Involvement of the Matrix and Nucleocapsid Domains of the Bovine Leukemia Virus Gag Polyprotein Precursor in Viral RNA Packaging  

UK PubMed Central (United Kingdom)

The RNA packaging process for retroviruses involves a recognition event of the genome-length viral RNA by the viral Gag polyprotein precursor (PrGag), an important step in particle morphogenesis. The...Full Text Available

2003-09-01

39

In vitro analysis of nuclear mRNA export using molecular beacons for target detection  

UK PubMed Central (United Kingdom)

A detailed molecular characterization of nuclear mRNA export will require an in vitro system, allowing a biochemical reconstitution of transport. To this end, an mRNA export assay has...Full Text Available

2003-06-01

40

Genomic but Not Antigenomic Hepatitis Delta Virus RNA Is Preferentially Exported from the Nucleus Immediately after Synthesis and Processing  

UK PubMed Central (United Kingdom)

Hepatitis delta virus (HDV) contains a viroid-like circular RNA that replicates via a double rolling circle replication mechanism. It is generally assumed that HDV RNA is synthesized and remains exclusively...Full Text Available

2002-04-01

41

Dose Optimization for Long-term rAAV-mediated RNA Interference in the Nigrostriatal Projection Neurons  

UK PubMed Central (United Kingdom)

Short-hairpin RNA (shRNA)–mediated gene knockdown is a powerful tool for targeted gene silencing and an emerging novel therapeutic strategy. Recent publications, however, reported unexpected...Full Text Available

2009-09-01

42

Differential expression of microRNA-675, microRNA-139-3p and microRNA-335 in benign and malignant adrenocortical tumours  

UK PubMed Central (United Kingdom)

BackgroundFor the clinical management of adrenocortical neoplasms it is crucial to correctly distinguish between benign and malignant tumours. Even histomorphologically based scoring...Full Text Available

2011-06-01

43

Detecting microRNA activity from gene expression data  

UK PubMed Central (United Kingdom)

BackgroundMicroRNAs (miRNAs) are non-coding RNAs that regulate gene expression by binding to the messenger RNA (mRNA) of protein coding genes. They control gene expression by either...Full Text Available

44

Computational Challenges in miRNA Target Predictions: To Be or Not to Be a True Target?  

UK PubMed Central (United Kingdom)

All microRNA (miRNA) target—finder algorithms return lists of candidate target genes. How valid is that output in a biological setting? Transcriptome analysis has proven to be a useful approach...Full Text Available

2009-01-01

45

A functional peptide encoded in the Escherichia coli 23S rRNA.  

UK PubMed Central (United Kingdom)

A pentapeptide open reading frame equipped with a canonical ribosome-binding site is present in the Escherichia coli 23S rRNA. Overexpression of 23S rRNA fragments containing the mini-gene renders cells...Full Text Available

1996-05-28

46

Locked nucleic acid (LNA): High affinity targeting of RNA for diagnostics and therapeutics  

DEFF Research Database (Denmark)

Locked nucleic acid (LNA) is a nucleic acid analogue containing one or more LNA nucleotide monomers with a bicyclic furanose unit locked in an RNA mimicking sugar conformation. This conformational restriction results in unprecedented hybridization affinity towards complementary single stranded RNA and thus, makes LNA uniquely suited for mimicking RNA structures and sequence specific targeting of RNA in vitro or in vivo. The focus of this paper is on LNAantisense, LNA-modified siRNA (siLNA), and detection and analysis of microRNAs by LNA-modified oligonucleotide probes.

2005-01-01

47

Stable Isotopes (?D, ?13C, ?15N) Reveal Associations Among Geographic Location and Condition of Alaskan Northern ...  

Science.gov (United States)

... M. Taylor, T. Kurt Kyser. (2009) Feather isotope analysis discriminates age-classes of Western, Least, and Semipalmated sandpipers when plumage ... ...

48

New approach to study fast and slow motions in lipid bilayers: application to dimyristoylphosphatidylcholine-cholesterol interactions.  

UK PubMed Central (United Kingdom)

Natural abundance 13C solid-state nuclear magnetic resonance spectroscopy was used to investigate the effect of the incorporation of cholesterol on the dynamics of dimyristoylphosphatidylcholine (DMPC)...Full Text Available

1995-05-01

49

Inhibition of Ribonucleic Acid Synthesis by Nalidixic Acid in Escherichia coli  

UK PubMed Central (United Kingdom)

The effect of low concentrations of nalidixic acid on ribonucleic acid (RNA) synthesis in Escherichia coli was examined. It was observed that RNA synthesis in exponentially growing...Full Text Available

1974-10-01

50

Utilization of a "1"3C enriched tracer for carbon flux studies in a tropical Eucalyptus exserta forest  

International Nuclear Information System (INIS)

Severe depletion of nutrients through removal of the above ground litter caused a cessation of growth of a Eucalyptus exserta forest in tropical China. Since there is no above ground input of C in this forest, microbial biomass (C_m_i_c) and soil organic C (C_o_r_g) are maintained by the below ground input only. By determining the maintenance requirement of the soil microflora, it should be possible to estimate the below ground production of this forest. To check this hypothesis the authors performed an experiment with labelled C. Since large scale production and field application of "1"4C labelled Eucalyptus litter were not feasible, 'naturally labelled' C_4 plant litter (Zea mays) was used. Maize litter has a #delta#"1"3C of -12.7 per mille as compared with a #delta#"1"3C of -30.7 per mille for Eucalyptus leaf litter. The "1"3C abundance is used to determine the amount of maize C in each of the soil layers. Investigations were made of how supplementation of the soil with litter ...

1990-10-01

51

Study of heavy-ion reactions with the unstable Nuclei, {sup 11}Be and {sup 13}N  

Energy Technology Data Exchange (ETDEWEB)

Heavy-ion reaction with unstable nuclei, {sup 13}N and {sup 11}Be, {sup 13}N+{sup 12}C and {sup 11}Be+{sup 12}C-{sup 10}Be+{sup 13}C were analyzed by a coupled-reaction-channel (CRC) method and formation of valence nucleon molecular orbital was studied by numerical analysing calculation. In this report, 1P1/2 (the ground state of {sup 13}N and {sup 13}C), 2s1/2 (the ground state of {sup 11}Be), 1d5/2 and 1d3/2 orbital were studied as one particle state of valance nucleon in {sup 13}N, {sup 13}C and {sup 11}Be. Moreover, d3/2 state, comparatively higher excited state, was contained into CRC calculation. The effect of this state on CRC scheme was proved very large. We developed new program code to obtain the numerical stable solution. It is necessary to about 200 MB (CRC equation) for {sup 11}Be+{sup 12}C{yields}{sup 10}Be+{sup ...

1996-06-01

52

Geochemical characteristics and origin of gases from the Upper, Lower Paleozoic and the Mesozoic reservoirs in the Ordos Basin, China  

Energy Technology Data Exchange (ETDEWEB)

The Ordos Basin, the second largest sedimentary basin in China, contains the broad distribution of natural gas types. So far, several giant gas fields have been discovered in the Upper and Lower Paleozoic in this basin, each having over 1000x10{sup 8}m{sup 3} of proven gas reserves, and several gas pools have also been discovered in the Mesozoic. This paper collected the data of natural gases and elucidated the geochemical characteristics of gases from different reservoirs, and then discussed their origin. For hydrocarbons preserved in the Upper Paleozoic, the elevated {delta}{sup 13}C values of methane, ethane and propane indicate that the gases would be mainly coal-formed gases; the singular reversal in the stable carbon isotopes of gaseous alkanes suggests the mixed gases from humic sources with different maturity. In the Lower Paleozoic, the {delta} {sup 13}C{sub 1} values are mostly similar with ...

2008-05-15

54

Termination of transcription by bacteriophage T3 RNA polymerase: homogeneous 3'-terminal oligonucleotide sequence of in vitro T3 RNA polymerase transcripts.  

UK PubMed Central (United Kingdom)

RNA was synthesized in vitro from a T3 DNA template by T3 RNA polymerase and subsequently separated into seven discrete size classes (molecular weights ranging between 0.21 x 10(6) and 6.2 x 10(6))...Full Text Available

1979-10-01

56

Interactions between tRNA identity nucleotides and their recognition sites in glutaminyl-tRNA synthetase determine the cognate amino acid affinity of the enzyme.  

UK PubMed Central (United Kingdom)

Sequence-specific interactions between aminoacyl-tRNA synthetases and their cognate tRNAs both ensure accurate RNA recognition and prevent the binding of noncognate substrates. Here we show for Escherichia...Full Text Available

1996-07-09

59

Cleavage of tRNA within the mature tRNA sequence by the catalytic RNA of RNase P: implication for the formation of the primer tRNA fragment for reverse transcription in copia retrovirus-like particles.  

UK PubMed Central (United Kingdom)

The retrovirus-like particles of Drosophila are intermediates of retrotransposition of the transposable element copia. In these particles, a 39-nucleotide-long fragment from the 5' region of Drosophila...Full Text Available

1990-10-01

60

Arginine aminoacylation identity is context-dependent and ensured by alternate recognition sets in the anticodon loop of accepting tRNA transcripts.  

UK PubMed Central (United Kingdom)

Yeast arginyl-tRNA synthetase recognizes the non-modified wild-type transcripts derived from both yeast tRNA(Arg) and tRNA(Asp) with equal efficiency. It discriminates its cognate natural substrate,...Full Text Available

1996-09-16

61

The nucleotide sequence and organization of nuclear 5S rRNA genes in yellow lupine  

International Nuclear Information System (INIS)

We have isolated a genomic clone containing 'Lupinus luteus' 5S ribosomal RNA genes by screening with 5S rDNA probe clones that were hybridized previously with the initiator methionine tRNA preparation (contaminated) with traces of rRNA or its degradation products). The clone isolated contains ten repeat units of 342 bp with 119 bp fragment showing 100% homology to the 5S rRNA from yellow lupine. Sequence analysis indicates only point heterogeneities among the flanking regions of the genes. (author). 6 refs, 3 figs.

1993-01-01

62

The origin of natural gas and the hydrocarbon charging history of the Yulin gas field in the Ordos Basin, China  

Energy Technology Data Exchange (ETDEWEB)

The genetic type, source and charging history of natural gas in the Yulin gas field in the Ordos Basin have been studied by combining the carbon isotopic composition of natural gas and geochemical characteristics of light hydrocarbons with carbon isotope fractionation model results and fluid inclusion analysis. The carbon isotopic composition of methane and ethane in the Yulin gas field is relatively enriched in {sup 13}C with {delta}{sup 13}C{sub 1} values ranging from - 35.3 permille to - 29.8 permille (average value = - 32.4 permille) and {delta}{sup 13}C{sub 2} ranging from - 26.3 permille to - 23.5 permille (average value = - 24.8 permille). The C{sub 7} light hydrocarbons are predominated by methylcyclohexane, accounting for 65.8% to 80.9% (average value = 71.6%), which is characteristic of coal-derived gas. Furthermore, the gas geochemistry indicates ...

2010-04-01

63

Stable carbon isotope compositions and source rock geochemistry of the giant gas accumulations in the Ordos Basin, China  

Energy Technology Data Exchange (ETDEWEB)

Ordos Basin, the second largest sedimentary basin in China, contains enormous natural gas resources. Each of the four giant gas fields discovered so far in this basin (i.e., Sulige, Yulin, Wushenqi and Jingbian) has over 100 billion cubic meters (bcm) or 3.53 trillion cubic feet (tcf) of proven gas reserves. This study examines the stable carbon isotope data of 125 gas samples collected from the four giant gas fields in the Ordos Basin. Source rocks in the Upper Paleozoic coal measures are suggested by the generally high {delta}{sup 13}C values of C{sub 2}-C{sub 4} gaseous hydrocarbons in the gases from the Sulige, Yulin and Wushenqi gas fields. The {delta}{sup 13}C values of methane, benzene and toluene in gases from the Lower Paleozoic reservoirs of the Jingbian field indicate a significant contribution from humic source rocks, as they are similar to those in the Upper Paleozoic reservoirs of the ...

2005-07-01

64

Regulation of human ribosomal RNA transcription.  

Science.gov (United States)

We have used a cell-free polymerase I transcription system derived from HeLa cells to study the regulation of human rRNA synthesis. Analysis of deletion mutants spanning the start site of transcription at nucleotide +1 indicates that the control region affecting initiation of human rRNA synthesis is contained within sequences from nucleotides -158 to +18. This promoter region can be subdivided into (i) a central segment of approximately 40 base pair that is required for transcription and (ii) flanking sequences that influence the efficiency of transcription in vitro. We have examined the in vitro transcriptional activity of the human extract under various conditions that are thought to modulate rRNA synthesis in vivo. Cell-free extracts prepared from HeLa cells infected with adenovirus 2 synthesize human rRNA at levels greatly decreased relative to uninfected cell extracts. By contrast, in vitro ...

1983-06-01

65

The origin of natural gas and the hydrocarbon charging history of the Yulin gas field in the Ordos Basin, China  

British Library Electronic Table of Contents (United Kingdom)

The genetic type, source and charging history of natural gas in the Yulin gas field in the Ordos Basin have been studied by combining the carbon isotopic composition of natural gas and geochemical characteristics of light hydrocarbons with carbon isotope fractionation model results and fluid inclusion analysis. The carbon isotopic composition of methane and ethane in the Yulin gas field is relatively enriched in ^1^3C with d^1^3C1 values ranging from -35.3%% to -29.8%% (average value=-32.4%%) and d^1^3C2 ranging from -26.3%% to -23.5%% (average value=-24.8%%). The C7 light hydrocarbons are predominated by methylcyclohexane, accounting for 65.8% to 80.9% (average value=71.6%), which is characteristic of coal-derived gas. Furthermore, the gas geochemistry indicates that, although marine lime...

2010-01-01

66

Sulfur and carbon cycling in a flue gas desulfurization sludge disposal site.  

Science.gov (United States)

Products of a power plant flue gas desulfurization scrubber are discharged into a pond as sludge consisting of calcite (initial delta13C 3.2-3.8 per thousand), gypsum (initial delta34S 7.6-8.6 per thousand), and aqueous solution. Reducing conditions exist below a boundary that appears to move vertically as a function of changes in pond water level. Under reducing conditions, bacteria partially reduce aqueous sulfate to low-delta34S sulfide, consuming organic carbon and generating low-delta13C bicarbonate. Under oxidizing conditions, sulfide is converted to sulfate, leading to calcite dissolution, gypsum precipitation, and isotopic re-equilibration of remaining calcite with dissolved bicarbonate near the pond surface. The gypsum has delta34S near 6 per thousand, and calcite has delta13C as low as -1.7 per thousand; the changes from initial values correspond to ...

2003-04-01

67

Structural studies of the O-antigenic polysaccharide from Escherichia coli O177  

British Library Electronic Table of Contents (United Kingdom)

The structure of the O-antigen polysaccharide (PS) from Escherichia coli O177 has been determined. Component analysis together with 1H and 13C NMR spectroscopy experiments was used to determine the structure. Inter-residue correlations were determined by 1H,13C-heteronuclear multiple-bond correlation and 1H,1H-NOESY experiments. PS is composed of tetrasaccharide repeating units with the following structure: 2)-a-l-Rhap-(13)-a-l-FucpNAc-(13)-a-l-FucpNAc-(13)-b-d-GlcpNAc-(1 An a-l-Rhap residue is suggested to be present at the terminal part of the polysaccharide, which on average is composed of 20 repeating units, since the 1H and 13C chemical shifts of an a-linked rhamnopyranosyl group could be assigned by a combination of 2D NMR spectra. Consequently, the biological repeating unit has a 3-...

2011-01-01

68

Novel recombinant insulin analogue with flexible C-terminus in B chain. NMR structure of biosynthetic engineered A22^G-B31^K-B32^R human insulin monomer in water/acetonitrile solution  

British Library Electronic Table of Contents (United Kingdom)

A tertiary structure of recombinant A22^G-B31^K-B32^R-human insulin monomer (insulin GKR) has been characterized by ^1H, ^1^3C NMR at natural isotopic abundance using NOESY, TOCSY, ^1H/^1^3C-GHSQC, and ^1H/^1^3C-GHSQC-TOCSY spectra. Translational diffusion studies indicate the monomer structure in water/acetonitrile (65/35vol.%). CSI analysis confirms existence of secondary structure motifs present in human insulin standard (HIS). Both techniques allow to establish that in this solvent recombinant insulin GKR exists as a monomer. Starting from structures calculated by the program CYANA, two different refinement protocols used molecular dynamics simulated annealing with the program AMBER; in vacuum (AMBER_VC), and including a generalized Born solvent model (AMBER_GB). From these calculation...

2011-01-01

69

Unilateral NMR, 13C CPMAS NMR spectroscopy and micro-analytical techniques for studying the materials and state of conservation of an ancient Egyptian wooden sarcophagus  

British Library Electronic Table of Contents (United Kingdom)

A multi-technique approach was employed to study a decorated Egyptian wooden sarcophagus (XXV?XXVI dynasty, Third Intermediate Period), belonging to the Museo del Vicino Oriente of the Sapienza University of Rome. Portable non-invasive unilateral NMR was applied to evaluate the conservation state of the sarcophagus. Moreover, using unilateral NMR, a non-invasive analytical protocol was established to detect the presence of organic substances on the surface and/or embedded in the wooden matrix. This protocol allowed for an educated sampling campaign aimed at further investigating the state of degradation of the wood and the presence of organic substances by 13C cross polarization magic angle spinning (CPMAS) NMR spectroscopy. The composition of the painted layer was analysed by optical micr...

2011-01-01

70

Tunable erbium-doped fiber ring laser for applications of infrared absorption spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

We fabricate a low noise erbium-doped fiber ring laser that can be continuously tuned over 102nm by insertion of the fiber Fabry-Perot tunable filter (FFP-TF) in the ring cavity with a novel cavity structure and the optimal gain medium length. As an application of this fiber ring laser, we performed the absorption spectroscopy of acetylene (13C2H2) and hydrogen cyanide (H13C14N) and measure the absorption spectra of more than 50 transition lines of these gases with an excellent signal to noise ratio (SNR). The pressure broadening coefficients of four acetylene transition lines are obtained using this fiber ring laser and an external cavity laser diode.

2007-01-01

71

Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation  

British Library Electronic Table of Contents (United Kingdom)

Summary: The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR res...

2006-01-01

72

Imazalil-cyclomaltoheptaose (beta-cyclodextrin) inclusion complex: preparation by supercritical carbon dioxide and 13C CPMAS and 1H NMR characterization.  

Science.gov (United States)

An inclusion complex between imazalil (IMZ), a selected fungicide, and cyclomaltoheptaose (beta-cyclodextrin, betaCD) was obtained using supercritical fluid carbon dioxide. The best preparation conditions were determined, and the inclusion complex was investigated by means of 1H NMR spectroscopy in aqueous solution and 13C CPMAS NMR spectroscopy in the solid state. Information on the geometry of the betaCD/IMZ complex was obtained from ROESY spectroscopy, while the dynamics of the inclusion complex in the kilohertz range was obtained from the proton spin-lattice relaxation times in the rotating frame, T(1rho) (1H). PMID:14553984

2003-10-10

73

Density separation of combustion-derived soot and petrogenic graphitic black carbon: Quantification and isotopic characterization  

Energy Technology Data Exchange (ETDEWEB)

The black carbon continuum is composed of a series of carbon-rich components derived from combustion or metamorphism and characterized by contrasting environmental behavior and susceptibility to oxidation. In this work, we present a micro-scale density fractionation method that allows isolating the small quantities of soot-like and graphitic material usually found in natural samples. Organic carbon and {delta}{sup 13}C mass balance calculations were used to quantify the relative contributions of the two fractions to thermally-stable organic matter from a series of aquatic sediments. Varying proportions of soot-like and graphitic material were found in these samples, with large variations in {delta}{sup 13}C signatures suggesting important differences in their origin and/or dynamics in the environment.

2009-01-01

74

Barium carbonate sediment sampling for inorganic dissolved carbon using isotope mass ratio spectrometer  

International Nuclear Information System (INIS)

This paperwork explain the method of water sampling to obtain the precipitate of BaCO3 solutions that will be used to analyze 13C from field work in Kelana Jaya, Selangor, Langkawi, Kedah and Taiping, Perak. The sampling involves collecting of water samples for groundwater from boreholes and surface water from canal, river, pond and ex-mining pond from several locations at the study sites. This study also elaborates the instruments and chemicals used. The main purpose of this sampling is to obtain the precipitate of BaCO3 for 13C analysis of dissolved inorganic carbon (DIC). A correct sampling method according to standard is very important to ensure an accurate and precise result. With this, the data from the laboratory analysis result can be fully utilized to make the interpretation of the pollutants movement. (Author)

2009-10-06

75

Unifying evolutionary and thermodynamic information for RNA folding of multiple alignments  

UK PubMed Central (United Kingdom)

Computational methods for determining the secondary structure of RNA sequences from given alignments are currently either based on thermodynamic folding, compensatory base pair substitutions or both....Full Text Available

2008-11-01

76

Unexpected diversity of RNase P, an ancient tRNA processing enzyme: challenges and prospects  

UK PubMed Central (United Kingdom)

For an enzyme functioning predominantly in a seemingly housekeeping role of 5′ tRNA maturation, RNase P displays a remarkable diversity in subunit make-up across the three domains of...Full Text Available

2010-01-21

77

Ubiquitin over-expression phenotypes and ubiquitin gene molecular misreading during aging in Drosophila melanogaster  

UK PubMed Central (United Kingdom)

Molecular Misreading (MM) is the inaccurate conversion of genomic information into aberrant proteins. For example, when RNA polymerase II transcribes a GAGAG motif it synthesizes at low frequency RNA...Full Text Available

78

Therapeutic potential of RNA interference in pain medicine  

UK PubMed Central (United Kingdom)

In recent years RNA interference (RNAi) has rapidly become the most widely used tool for gene knockdown due to its high specificity and potency. RNAi is an evolutionarily conserved mechanism...Full Text Available

2009-01-01

79

The viroid and viroid-like RNA database.  

UK PubMed Central (United Kingdom)

The viroid and viroid-like RNA database is a compilation of all natural sequences published in journals or available from the GenBank and EMBL nucleotide sequence libraries. Several information regarding...Full Text Available

1998-01-01

80

The RNA Chaperone Hfq Is Important for Growth and Stress Tolerance in Francisella novicida  

UK PubMed Central (United Kingdom)

The RNA-binding protein Hfq is recognized as an important regulatory factor in a variety of cellular processes, including stress resistance and pathogenesis. Hfq has been shown in several bacteria to...Full Text Available

81

Subunits of the Drosophila CCR4-NOT complex and their roles in mRNA deadenylation  

UK PubMed Central (United Kingdom)

The CCR4-NOT complex is the main enzyme catalyzing the deadenylation of mRNA. We have investigated the composition of this complex in Drosophila melanogaster by immunoprecipitation...Full Text Available

2010-07-01

82

Studying bacterial transcriptomes using RNA-seq  

UK PubMed Central (United Kingdom)

Genome-wide studies of bacterial gene expression are shifting from microarray technology to second generation sequencing platforms. RNA-seq has a number of advantages over hybridization-based techniques,...Full Text Available

2010-10-01

83

Short RNA half-lives in the slow-growing marine cyanobacterium Prochlorococcus  

UK PubMed Central (United Kingdom)

BackgroundRNA turnover plays an important role in the gene regulation of microorganisms and influences their speed of acclimation to environmental changes. We investigated whole-genome...Full Text Available

2010-01-01

84

Relationship between mRNA secondary structure and sequence variability in Chloroplast genes: possible life history implications  

UK PubMed Central (United Kingdom)

BackgroundSynonymous sites are freer to vary because of redundancy in genetic code. Messenger RNA secondary structure restricts this freedom, as revealed by previous findings in...Full Text Available

86

RNA polymerase II trigger loop residues stabilize and position the incoming nucleotide triphosphate in transcription  

UK PubMed Central (United Kingdom)

A structurally conserved element, the trigger loop, has been suggested to play a key role in substrate selection and catalysis of RNA polymerase II (pol II) transcription elongation. Recently resolved...Full Text Available

2010-09-07

87

Purification of mRNA guanylyltransferase from calf thymus.  

UK PubMed Central (United Kingdom)

mRNA guanylyltransferase has been extensively purified from calf thymus. A GTP-binding assay was used based on the observations by Shuman and Hurwitz (1981) and Venkatesan and Moss (1982) that vaccinia...Full Text Available

1982-01-01

88

Probing the structural hierarchy and energy landscape of an RNA T-loop hairpin  

UK PubMed Central (United Kingdom)

The T-loop motif is an important recurrent RNA structural building block consisting of a U-turn sub-motif and a UA trans Watson–Crick/Hoogsteen base pair. In the presence of...Full Text Available

2007-11-01

89

Palindromic Sequence Plays a Critical Role in Human Foamy Virus Dimerization  

UK PubMed Central (United Kingdom)

The retroviral RNA genome is dimeric, consisting of two identical strands of RNA linked near their 5′ ends by a dimer linkage structure. Previously it was shown that human foamy virus (HFV)...Full Text Available

2001-04-01

90

Nuclear Organization and Dynamics of 7SK RNA in Regulating Gene Expression  

UK PubMed Central (United Kingdom)

Noncoding RNAs play important roles in various aspects of gene regulation. We have identified 7SK RNA to be enriched in nuclear speckles or interchromatin granule clusters (IGCs), a subnuclear domain...Full Text Available

2010-12-01

91

Naturally occurring double-stranded RNA and immune responses. Effects on plaque-forming cells and antibody formation.  

UK PubMed Central (United Kingdom)

A highly purified preparation of double-stranded RNA, obtained from virus-like particles in Penicillium cultures, was found to affert humoral immune responses in mice differentially depending on its...Full Text Available

1975-03-01

92

Mode of Action of RNase BN/RNase Z on tRNA Precursors  

UK PubMed Central (United Kingdom)

RNase BN, the Escherichia coli homolog of RNase Z, was previously shown to act as both a distributive exoribonuclease and an endoribonuclease on model RNA substrates and to be inhibited...Full Text Available

2010-07-23

93

MicroRNAs and small interfering RNAs can inhibit mRNA expression by similar mechanisms  

UK PubMed Central (United Kingdom)

MicroRNAs (miRNAs) are endogenously encoded small noncoding RNAs, derived by processing of short RNA hairpins, that can inhibit the translation of mRNAs bearing partially complementary target sequences....Full Text Available

2003-08-19

94

Making the message clear: visualizing mRNA localization  

UK PubMed Central (United Kingdom)

Localized mRNA provides spatial and temporal protein expression essential to cell development and physiology. To explore the mechanisms involved, considerable effort has been spent in establishing new...Full Text Available

2010-07-01

95

Long-term impact of acyclovir suppressive therapy on genital and plasma HIV RNA in Tanzanian women: a randomised controlled trial  

UK PubMed Central (United Kingdom)

BackgroundHerpes simplex virus (HSV) suppressive therapy reduces genital and plasma HIV-1 RNA over periods up to three months but the longer-term effect is unknown.Full Text Available

2010-05-01

96

In vitro dimerization of human immunodeficiency virus type 1 (HIV-1) spliced RNAs  

UK PubMed Central (United Kingdom)

The human immunodeficiency virus type 1 (HIV-1) packages its genomic RNA as a dimer of homologous RNA molecules that has to be selected among a multitude of cellular and viral RNAs. Interestingly, spliced...Full Text Available

2007-12-01

97

Improved free-energy parameters for predictions of RNA duplex stability.  

UK PubMed Central (United Kingdom)

Thermodynamic parameters for prediction of RNA duplex stability are reported. One parameter for duplex initiation and 10 parameters for helix propagation are derived from enthalpy and free-energy changes...Full Text Available

1986-12-01

98

Heat Stress Enhances the Accumulation of Polyadenylated Mitochondrial Transcripts in Arabidopsis thaliana  

UK PubMed Central (United Kingdom)

BackgroundPolyadenylation of RNA has a decisive influence on RNA stability. Depending on the organisms or subcellular compartment, it either enhances transcript stability or targets...Full Text Available

99

Emergence of Klebsiella pneumoniae Coproducing KPC-2 and 16S rRNA Methylase ArmA in Poland ?  

UK PubMed Central (United Kingdom)

A Klebsiella pneumoniae epidemic strain that coproduced carbapenemase KPC-2 (K. pneumoniae carbapenemase 2) and 16S rRNA methylase ArmA has emerged in Poland. Four...Full Text Available

2011-01-01

100

Efficient use of accessibility in microRNA target prediction  

UK PubMed Central (United Kingdom)

Considering accessibility of the 3′UTR is believed to increase the precision of microRNA target predictions. We show that, contrary to common belief, ranking by the hybridization energy or by...Full Text Available

2011-01-01

101

Differential targeting of Tetrahymena ORC to ribosomal DNA and non-rDNA replication origins  

UK PubMed Central (United Kingdom)

The Tetrahymena thermophila origin recognition complex (ORC) contains an integral RNA subunit, 26T RNA, which confers specificity to the amplified ribosomal DNA (rDNA) origin by base...Full Text Available

2009-02-04

102

Detection of Ockelbo virus RNA in skin biopsies by polymerase chain reaction.  

UK PubMed Central (United Kingdom)

A sensitive assay based on the polymerase chain reaction for the detection of Ockelbo virus RNA was developed. Two primer pairs from the gene coding for the E2 glycoprotein were chosen. By use of a...Full Text Available

1993-08-01

103

Confocal microscopy for the analysis of siRNA delivery by polymeric nanoparticles  

UK PubMed Central (United Kingdom)

Clinical applications of genetic therapies, including delivery of short, interfering RNAs (siRNAs) for RNA interference (RNAi), are limited due to the difficulty of delivering nucleic acids...Full Text Available

2010-09-01

104

Computing the Partition Function for Kinetically Trapped RNA Secondary Structures  

UK PubMed Central (United Kingdom)

An RNA secondary structure is locally optimal if there is no lower energy structure that can be obtained by the addition or removal of a single base pair, where energy is defined according...Full Text Available

105

Characterization of the 5'-terminal cap structures of early simian virus 40 mRNA.  

UK PubMed Central (United Kingdom)

Early simian virus 40-specific mRNA was isolated from lytically infected and stably transformed cells and analyzed with respect to the 5'-terminal cap content. An analogous diversity of capped structures...Full Text Available

1980-09-01

106

Centromere-encoded RNAs are integral components of the maize kinetochore  

UK PubMed Central (United Kingdom)

RNA is involved in a variety of chromatin modification events, ranging from large-scale structural rearrangements to subtle local affects. Here, we extend the evidence for RNA–chromatin interactions...Full Text Available

2004-11-09

107

An Efficient Fungal RNA-Silencing System Using the DsRed Reporter Gene?  

UK PubMed Central (United Kingdom)

In filamentous fungi, RNA silencing is an attractive alternative to disruption experiments for the functional analysis of genes. We adapted the gene encoding the autofluorescent DsRed protein as a reporter...Full Text Available

2007-02-01

108

A structural determinant required for RNA editing  

UK PubMed Central (United Kingdom)

RNA editing by adenosine deaminases acting on RNAs (ADARs) can be both specific and non-specific, depending on the substrate. Specific editing of particular adenosines may depend on the overall sequence...Full Text Available

2011-07-01

109

A bacterial amber suppressor in Saccharomyces cerevisiae is selectively recognized by a bacterial aminoacyl-tRNA synthetase.  

UK PubMed Central (United Kingdom)

Little is known about the conservation of determinants for the identities of tRNAs between organisms. We showed previously that Escherichia coli tyrosine tRNA synthetase can charge the Saccharomyces...Full Text Available

1990-04-01

110

Wide cross-species aminoacyl-tRNA synthetase replacement in vivo: yeast cytoplasmic alanine enzyme replaced by human polymyositis serum antigen.  

UK PubMed Central (United Kingdom)

Because of variations in tRNA sequences in evolution, tRNA synthetases either do not acylate their cognate tRNAs from other organisms or execute misacylations which can be deleterious in vivo. We report...Full Text Available

1995-05-23

111

The Acidic Domain of Hepatitis C Virus NS4A Contributes to RNA Replication and Virus Particle Assembly?  

UK PubMed Central (United Kingdom)

Hepatitis C virus NS3-4A is a membrane-bound enzyme complex that exhibits serine protease, RNA helicase, and RNA-stimulated ATPase activities. This enzyme complex is essential for viral genome replication...Full Text Available

2011-02-01

112

Targeted suppression of Has2 mRNA in mouse cumulus cell-oocyte complexes by adenovirus-mediated short-hairpin RNA expression  

UK PubMed Central (United Kingdom)

RNA interference (RNAi) is an effective tool for studying gene function in oocytes, but no studies have targeted somatic cells of primary cultured cumulus cell-oocyte complexes (COCs). This...Full Text Available

2009-06-01

113

Nucleotide sequence of a Euglena gracilis chloroplast gene coding for the 16S rRNA: homologies to E. coli and Zea mays chloroplast 16S rRNA.  

UK PubMed Central (United Kingdom)

The nucleotide sequence of 16S rDNA from Euglena gracilis chloroplasts has been determined representing the first complete sequence of an algal chloroplast rRNA gene. The structural part of the 16S...Full Text Available

1982-10-25

114

Isolation and sequence determination of 5'-terminal oligonucleotide fragments of RNA transcripts synthesized by bacteriophage T3-induced RNA polymerase from T3 DNA.  

UK PubMed Central (United Kingdom)

The nucleotide sequence of the 5'-terminal oligonucleotides produced by pancreatic RNase digestion of bacteriophage T3 RNA polymerase (EC 2.7.7.6) transcripts of T3 DNA has been determined. The sequence...Full Text Available

1980-07-01

115

Cloning of rice DNA and identification of tRNA gene clones  

Energy Technology Data Exchange (ETDEWEB)

DNA from 48 hr germinated rice embryos was cut with restriction endonuclease Bam H1 and cloned to the Bam H1 site on plasmid pBR 322. The clones containing recombinant DNA were selected by their sensitivity to tetracycline and resistance to ampicillin. Using /sup 32/P-labelled rice embryos tRNA as a probe two clones were identified to contain tRNA genes by colony hybridization.

1981-10-20

116

Characterization and engineering of sequences controlling in vivo synthesis of brome mosaic virus subgenomic RNA.  

UK PubMed Central (United Kingdom)

Expression of brome mosaic virus (BMV) coat protein and internal genes of many other positive-strand RNA viruses requires initiation of subgenomic mRNA synthesis from specific internal sites on minus-strand...Full Text Available

1988-07-01

117

Current applications of magnetic resonance in coal liquefaction research  

Energy Technology Data Exchange (ETDEWEB)

Some applications of magnetic resonance in coal liquefaction research described briefly are: (1) investigation of the nature of carbon deposits on used coal-liquefaction catalysts, (2) determination of the fate of hydrogen during coal liquefaction, and (3) observation of transient free radicals during coal pyrolysis. The first two applications make use of cross-polarization /sup 13/C magnetic resonance combined with magic angle spinning, and the third application is an electron spin resonance study. (BLM)

1982-01-01

118

Crystal growth of epitaxial CVD diamond using [sup 13]C isotope and characterization of dislocations by Raman spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

[sup 13]C epitaxial diamond films have been grown on [sup 12]C-type IIb diamond substrates doped with boron, using electron assisted chemical vapor deposition. The relation between etch pits to dislocations in [sup 13]C diamond film and the broadening of the first-order Raman peak was examined. The reactant gas was [sup 13]CH[sub 4] of > 99% purity. The substrate temperature was varied from 943 to 1300 C. The uneven surface morphology was confirmed by atomic force microscopy (AFM) and laser microscopy. From 943 to 1030 C, etch pit rows along left angle 100 right angle were observed. At 991 C, the etch pit density on a row was 3300 to 5000 pits/cm. The Ar[sup +] laser beam was focused on a transparent area near the row of etch pits, where the boron impurity of the substrate is less than several 10 ppm. The first-order Raman line of [sup 13]C epitaxial diamond ...

1993-03-01

119

Climate controls on forest soil C isotope ratios in the southern Appalachian Mountains  

Energy Technology Data Exchange (ETDEWEB)

A large portion of terrestrial carbon (C) resides in soil organic carbon (SOC). The dynamics of this large reservoir depend on many factors, including climate. Measurements of {sup 13}C:{sup 12}C ratios, C concentrations, and C:N ratios at six forest sites in the Southern Appalachian Mountains (USA) were used to explore several hypotheses concerning the relative importance of factors that control soil organic matter (SOM) decomposition and SOC turnover. Mean {delta}{sup 13}C values increased with soil depth and decreasing C concentrations along a continuum from fresh litter inputs to more decomposed soil constituents. Data from the six forest sites, in combination with data from a literature review, indicate that the extent of change in {delta}{sup 13}C values from forest litter inputs to mineral soil (20 cm deep) is significantly associated with mean annual ...

2000-04-01

120

Characterization of polymers for microcellular foams  

Energy Technology Data Exchange (ETDEWEB)

We have measured, by {sup 1}H and {sup 13}C nuclear magnetic resonance (NMR), the percent deuteration, the tacticity and the purity of several polymers and one solvent used in the preparation of microcellular foams. The percent deuteration was measured for polystyrene, polyacrylonitrile and polyethylene. The tacticities of polystyrene and polyacrylonitrile were determined. The purity and degradation products of polyacrylonitrile and maleic anhydride were examined. This report documents the experimental procedures and results of these measurements.

1992-03-01

121

Molecular environment of the IIId subdomain of the IRES element of hepatitits C virus RNA on the human 40S ribosomal subunit  

British Library Electronic Table of Contents (United Kingdom)

The molecular environment of the key subdomain IIId of the internal ribosome entry site (IRES) element of hepatitis C virus (HCV) RNA in the binary complex with the human 40S ribosomal subunit was studied. To this end, HCV IRES derivatives bearing perfluorophenylazido groups activatable by mild UV at nucleotides G263 or A275 in the subdomain IIId stem were used. They were prepared by the complementary addressed modification of the corresponding RNA transcript with alkylating oligodeoxyribonucleotide derivatives. None of the RNA derivatives were shown to be crosslinked to the 18S rRNA. It was found that the photoreactive groups of the IRES G263 and A275 nucleotides are crosslinked to ribosomal proteins S3a, S14, and S16. For the IRES derivative with the photoreactive group in nucleotide G26...

2009-01-01

122

Effect of Diaporthe RNA virus 1 (DRV1) on growth and pathogenicity of different Diaporthe species  

British Library Electronic Table of Contents (United Kingdom)

A 4.1?kbp positive-strand RNA virus known as Diaporthe RNA virus 1 (DRV1) occurs in hypovirulent, non-sporulating isolates of the fungal pathogen Diaporthe perjuncta. A full-length cDNA clone of DRV1 was developed and RNA transcribed from the cDNA clone used to transfect different Diaporthe spp. The transfected species included three D. ambigua isolates and an unidentified Phomopsis asexual state of a Diaporthe sp. Successful transfections were confirmed using RT-PCR. Although the in vitro-transcribed positive sense single-stranded RNA used for transfection included vector sequences at both ends, the genomes of progeny virus from DRV1-transfected isolates were free of the vector sequences. Transfection resulted in morphological changes in these fungal pathogens. However, the presence of DR...

2011-01-01

123

The vasopressin mRNA poly(A) tract is unusually long and increases during stimulation of vasopressin gene expression in vivo  

Energy Technology Data Exchange (ETDEWEB)

The authors developed a method, termed an H-blot, by which the poly(A) tract of any specific mRNA may be detected by RNA filter hybridization after its removal from the body of the mRNA by a RNase H-catalyzed endonucleolytic cleavage in the 3' untranslated region. Using this method, they studied the modulation of the length of the poly(A) tract of rat vasopressin mRNA in vivo during changes in the levels of this mRNA resulting from a physiologic stimulus, osmotic stress. The poly(A) tract of hypothalamic vasopressin mRNA in hydrated rats was, quite remarkably, --250 nucleotides in length, in contrast to that of somatostatin mRNA, which was --30 nucleotides long. Vasopressin mRNA poly(A) tail length increased progressively from --250 to --400 nucleotides with the application of the hyperosmotic stimulus and ...

1988-06-01

124

Evolution of a molecular switch: universal bacterial GTPases regulate ribosome function.  

Science.gov (United States)

The GTPases comprise a protein superfamily of highly conserved molecular switches adapted to many diverse functions. These proteins are found in all domains of life and often perform essential roles in fundamental cellular processes. Analysis of data from genome sequencing projects demonstrates that bacteria possess a core of 11 universally conserved GTPases (elongation factor G and Tu, initiation factor 2, LepA, Era, Obg, ThdF/TrmE, Ffh, FtsY, EngA and YchF). Investigations aimed at understanding the function of GTPases indicate that a second conserved feature of these proteins is that they elicit their function through interaction with RNA and/or ribosomes. An emerging concept suggests that the 11 universal GTPases are either necessary for ribosome function or transmitting information from the ribosome to downstream targets for the purpose of generating specific cellular responses. Furthermore, it is suggested that progenitor GTPases were early regulators of ...

2001-07-01

125

Boron-Dependent Degradation of NIP5;1 mRNA for Acclimation to Excess Boron Conditions in Arabidopsis.  

Science.gov (United States)

Boron (B) is an essential plant micronutrient that is toxic at higher levels. NIP5;1 is a boric acid channel required for B uptake and growth under B deficiency. Accumulation of the NIP5;1 transcript is upregulated under B deficiency in Arabidopsis thaliana roots. To elucidate the mechanism of regulation, the 5' untranslated region (UTR) of NIP5;1 was tested for its ability to confer B-dependent regulation using ?-glucuronidase and green fluorescent protein as reporters. This analysis showed that the 5' UTR was involved in NIP5;1 transcript accumulation in response to B conditions. We also found that high-B conditions trigger NIP5;1 mRNA degradation and that the sequence from +182 to +200 bp in the 5' UTR is required for this mRNA destabilization. In the nip5;1-1 mutant background, a NIP5;1 complementation construct without the 5' UTR produced high levels of mRNA accumulation, increased B concentrations in tissues, and ...

2011-09-01

126

The prospects for polarized target materials with pure carbon background  

Science.gov (United States)

None of the materials presently in common use for polarized proton targets has a pure carbon nuclear background. The alcohols and diols contain some oxygen, and the ammonia and amine-based materials contain nitrogen and/or other noncarbon species. In the latter cases the noncarbon nuclei are measurably polarized as a concomitant of the process used to polarize the hydrogen nuclei. The relative simplicity of a pure carbon background would be advantageous for most types of scattering experiments and perhaps crucial for some. In addition to simplifying the kinematics of background events, pure carbon is relatively easy to prepare as a dummy'' target for background subtraction. Also, in such a target material, [sup 13]C-enrichment would yield a clean polarized [sup 13]C material. In this note I explore the possibilities for such materials, touching upon only what I consider to be the ...

1992-10-06

127

Synthesis, characterization and antitumor activity study of some cyclometalated organoplatinum(II) complexes containing aromatic N-donor ligands  

British Library Electronic Table of Contents (United Kingdom)

A general approach has been designed to synthesize some mononuclear and binuclear cyclometalated platinum(II) complexes, containing aromatic N-donor ligands with the presence of one Cl- trans to carbon. In this way, cyclometalated platinum(II) complex [Pt(C^N)Cl(dmso)], 1, C^N = N(1),C(2prime)-chelated, deprotonated 2-phenylpyridine and dmso = dimethylsulfoxide, was used as a precursor to react with imidazole derivatives (1-methylimidazole, 2a, imidazole, 2b,), monodentate pyridine derivatives (4-methylpyridine, 2c, pyridine, 2d,) and bidentate pyridine derivative (4,4prime-bipyridine, 3 and 4,). Synthesized complexes were fully characterized by using multinuclear NMR spectroscopy (1H, 13C{1H} and 195Pt), correlation NMR spectroscopy (1H-1H COSY, 13C{1H}-1H Heteronuclear Multiple Quantum C...

2011-01-01

128

Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation  

Energy Technology Data Exchange (ETDEWEB)

The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR resonances than the linear polymers poly(allylamine) (PAA) and poly(vinylamine) (PVA). These results are understood in terms of ...

2006-03-01

129

Kinetic studies of preactivated derivatives of cyclophosphamide by "3"1P NMR spectroscopy  

International Nuclear Information System (INIS)

Selected derivatives of cyclophosphamide (CP) metabolites were synthesized and the solution chemistry of each was studied by "3"1P nuclear magnetic resonance (NMR) spectroscopy under a standard set of reaction conditions at physiological pH (7.4) and temperature (37"0C). Complementary "2H and "1"3C NMR spectral data was obtained using isotopically ("2G and "1"3C) enriched CP metabolites. The CP derivatives were synthesized by the ozonolysis of substituted 3-butenyl phosphorodiamidates, and were isolated as analogues of either cis and trans 4-hydroperoxy-CP or aldophosphamide (AP). The relative ratios of the tautomeric species, 4-hydroxy-CP and AP, and their half-lives (T/sub 1/2/) were measured by "3"1P NMR spectroscopy. The influence of CP metabolites on perfused U-937 cells, a CP-sensitive human lymphoma, was observed by high resolution "3"1P NMR spectroscopy. In this manner, it was possible to measure, for the first time, a rate constant for the intracellular disappearance of ...

130

Crystalline O,O'-di-sec-butyl and O,O'-diethyl dithiophosphate platinum(II) complexes: Synthesis, 13C and 31P CP/MAS NMR, single crystal X-ray diffraction studies and thermal behaviour  

British Library Electronic Table of Contents (United Kingdom)

Crystalline bis(O,O'-di-sec-butyldithiophosphato)platinum(II) was prepared and studied by means of 13C, 31P CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. The unit cell of the platinum(II) compound is comprised of one centrosymmetric mononuclear molecule [Pt{S2P(O-sec-C4H9)2}2], in which the dithiophosphate groups display structural equivalence in both 31P NMR and XRD data. A pair of the dithiophosphate ligands exhibit the same S,S'-bidentate chelating structural function and form two planar four-membered chelate rings, [PtS2P], in this molecule. The planar configuration of the [PtS4] chromophore in structure 1 is governed by the dsp2-hybrid state of platinum(II). The structural states of the dithiophosphate groups in two different samples of complex 1 (one crystallised from...

2011-01-01

131

[Molecular analysis of cytoplasmic male sterility]. Progress report, June 1, 1989--June 15, 1991  

Energy Technology Data Exchange (ETDEWEB)

We have determined the actual RNA sequence of four mitochondrial genes: pcf, nad3, rps12, and coxII. Because plant mitochondrial proteins cannot be predicted from DNA sequences, the actual primary structures of the encoded proteins were unknown. We have gained information concerning the process of RNA editing. Editing can occur before splicing. Our data is consistent with the hypothesis that RNA editing is not simultaneous with transcription. Unlike other systems, the process of editing in plant does not exhibit a discernable direction. As a result of our RNA editing studies, we have produced a number of clones of the proper coding regions tube used for incorporating these mitochondrial genes into the nucleus. 6 refs., 4 figs.

1991-12-31

132

Stochastic kinetics of ribosomes: single motor properties and collective behavior  

CERN Document Server

Synthesis of protein molecules in a cell are carried out by ribosomes. A ribosome can be regarded as a molecular motor which utilizes the input chemical energy to move on a messenger RNA (mRNA) track that also serves as a template for the polymerization of the corresponding protein. The forward movement, however, is characterized by an alternating sequence of translocation and pause. Using a quantitative model, which captures the mechanochemical cycle of an individual ribosome, we derive an {\\it exact} analytical expression for the distribution of its dwell times at the successive positions on the mRNA track. Inverse of the average dwell time satisfies a ``Michaelis-Menten-like'' equation and is consistent with the general formula for the average velocity of a molecular motor with an unbranched mechano-chemical cycle. Extending this formula appropriately, we also derive the exact force-velocity relation for a ribosome. ...

2009-01-01

133

Stochastic gene expression and its consequences  

UK PubMed Central (United Kingdom)

Gene expression is a fundamentally stochastic process, with randomness in transcription and translation leading to significant cell-to-cell variations in mRNA and protein levels. This variation...Full Text Available

2008-10-17

134

Small Regulatory RNA and Legionella pneumophila  

UK PubMed Central (United Kingdom)

Legionella pneumophila is a gram-negative bacterial species that is ubiquitous in almost any aqueous environment. It is the agent of Legionnaires’ disease, an acute and often...Full Text Available

135

Separation of oligo-RNA by reverse-phase HPLC.  

UK PubMed Central (United Kingdom)

A rapid and highly reproducible chromatographic technique has been developed for analysis and purification of complex mixtures of oligoribonucleotides. The method utilizes a column of microparticulate...Full Text Available

1979-10-25

136

Mutations in RNA Binding Protein Gene Cause Familial Dilated Cardiomyopathy  

UK PubMed Central (United Kingdom)

ObjectivesWe sought to identify a novel gene for dilated cardiomyopathy (DCM).BackgroundDCM is a heritable, genetically...Full Text Available

2009-09-01

137

Isolation of full-length putative rat lysophospholipase cDNA using improved methods for mRNA isolation and cDNA cloning  

Energy Technology Data Exchange (ETDEWEB)

The authors have cloned a full-length putative rat pancreatic lysophospholipase cDNA by an improved mRNA isolation method and cDNA cloning strategy using (/sup 32/P)-labelled nucleotides. These new methods allow the construction of a cDNA library from the adult rat pancreas in which the majority of recombinant clones contained complete sequences for the corresponding mRNAs. A previously recognized but unidentified long and relatively rare cDNA clone containing the entire sequence from the cap site at the 5' end to the poly(A) tail at the 3' end of the mRNA was isolated by single-step screening of the library. The size, amino acid composition, and the activity of the protein expressed in heterologous cells strongly suggest this mRNA codes for lysophospholipase.

1987-03-24

139

Identification of pork derivatives in food products by species-specific polymerase chain reaction (PCR) for halal verification  

British Library Electronic Table of Contents (United Kingdom)

Pork identification in four types of food products, which are sausages and the casings, bread and biscuits, using species-specific polymerase chain reaction (PCR) detection of a conserved region in the mitochondrial (mt) 12S ribosomal RNA (rRNA) gene was developed. Genomic DNA of the food products were successfully extracted except for the casing samples, where no genomic DNA was detected. The extracted genomic DNA was then subjected to PCR amplification targeting the specific regions of the 12S rRNA gene. The genomic DNA from the food products were found to be of good quality and produced clear PCR products on the amplification of 12S rRNA gene of 387 base pairs (bp) from pork species. The species-specific PCR identification yielded excellent results for identification of pork derivatives...

2007-01-01

141

Curcumin Binding to DNA and RNA  

British Library Electronic Table of Contents (United Kingdom)

Curcumin, the yellow pigment from the rhizoma of Curcuma longa, is a widely studied phytochemical with a variety of biological activities. The ongoing research and clinical trials have proved that this natural phenolic compound has great and diverse pharmacological potencies. Beside its effective antioxidant, antiinflammatory, and antimicrobial/antiviral properties, curcumin is also considered as a cancer chemopreventive agent. While the antioxidant activity of curcumin is well documented, its interaction with DNA and RNA is not fully investigated. This study was designed to examine the interactions of curcumin with calf thymus DNA and yeast RNA in aqueous solution at physiological conditions, using constant DNA and RNA concentration (6.25?mM) and various curcumin/polynucleotide (phosphate...

2009-01-01

142

On the mechanism of the nonmonotonic relaxation processes in the metallic melts  

International Nuclear Information System (INIS)

The numerical analysis of the experimental data on viscosity change by time in the period after fast heating and crystal-liquid phase transition for the copper nonequilibrium melts and the Fe_7_0Cr_1_0P_1_3C_7 glass-forming melt near their melting temperatures is accomplished through the method of correlation functions and the Rytov-Dimentberg criterion. The observed dependences have nonmonotonic oscillating character but they do not relate to auto-oscillations. The proposed theoretical model of the properties oscillations origination by relaxation in the nonequilibrium liquids explains them as manifestation of noise-induced transitions in the metastable area near the critical temperatures (melting, structural transitions)

2000-01-01

143

NMR use in structural determination of natural products from Brazilian northeast plants; Uso de RMN na determinacao estrutural de produtos naturais de plantas nordestinas  

Energy Technology Data Exchange (ETDEWEB)

This work has carried out a molecular structure characterization of two Brazilian plants, Harpalyce brasiliana Benth and Bredemeyera floribunda Wild, using {sup 1} H and {sup 13} C NMR spectroscopy. NMR spectra were presented and analysed, then several structures have been proposed based on spectral data, and finally the structural determination was done 3 refs., 4 figs., 1 tab.

1995-12-31

144

Improved SSAMS performance  

British Library Electronic Table of Contents (United Kingdom)

We operate a new NEC 250kV single-stage accelerator mass spectrometer (SSAMS) next to our established 5MV tandem. This permits good comparison of 14C-AMS and challenges SSAMS performance. Initial SSAMS ion-optical deficiencies have been addressed by shimming the injection magnet and 3permil 14C/13C measurement with background limited by sample chemistry is routine. Higher-precision analysis is also achievable. A problematic measurement interference remains, however. The small spectrometer was procured to add measurement capacity, and for experiments with positive ions, but is now the preferred instrument for both convenience and measurement quality.

2010-01-01

145

Effects of Acetate Competition, pH and Soil Structure on the Rates and Pathways of Methane Formation in Tropical Rain Forest Soils  

Science.gov (United States)

The C isotopic composition of CH4 emissions are strongly influenced by the pathway of CH4 formation. Contrary to data from other freshwater systems, soil gas and surface flux measurements made in the tropical rain forests of Puerto Rico strongly suggest that CH4 produced in these environments was derived from CO2 reduction, rather than from acetate consumption. This study explored the effects of bacterial competition for acetate, pH, and soil structure on the pathways of CH4 formation in tropical rain forest soils. Our goal was to test two principal hypotheses: (1) ferric iron-reducing bacteria out-competed methanogens for acetate, resulting in greater CO2 reduction rather than aceticlastic methanogenesis, and (2) the low pH of tropical rain forest soils favors CO2 reduction rather than aceticlastic methanogenesis. In addition, this study also investigated the effect of destroying soil aggregate structure on the pathways and rates of CH4 production. Ferric iron-reducing bacteria ...

2004-12-01

146

Methionine kinetics in adult men: effects of dietary betaine on L-[2H3-methyl-1-13C]methionine  

International Nuclear Information System (INIS)

The effects of a daily 3-g supplement of betaine on kinetic aspects of L-[2H3-methyl-1-13C]methionine (MET) metabolism in healthy young adult men were explored. Four groups of four subjects each were given a control diet, based on an L-amino acid mixture supplying 29.5 and 21.9 mg.kg-1.d-1 of L-methionine and L-cystine for 4 d before the tracer study, conducted on day 5 during the fed state. Two groups received the control diet and two groups received the betaine supplement. Tracer was given intravenously (iv) or orally. The transmethylation rate of MET (TM), homocysteine remethylation (RM), and oxidation of methionine were estimated from plasma methionine labeling and 13C enrichment of expired air. RM tended to increase (P = 0.14) but the TM and methionine oxidation were significantly (P less than 0.05) higher after betaine supplementation when estimated with the oral tracer. No differences were ...

147

Enzymatic synthesis and carbon-13 nuclear magnetic resonance conformational studies of disaccharides containing. beta. -D-galactopyranosyl and. beta. -D-(1-/sup 13/C)Galactopyranosyl residues  

Energy Technology Data Exchange (ETDEWEB)

Partially purified UDPgalactosyltransferase (EC 2.4.1.22) from bovine milk has been used to synthesize millimolar amounts of compounds such as Gal..beta..(1..-->..4)Glc, Gal..beta..(1..-->..4)GlcNAc-..beta..-hexanolamine, and Gal..beta..(1..-->..4)-GlcNAc..beta..(1..-->..4)GlcNAc. The same method has been used to prepare similar compounds containing /sup 13/C-enriched galactopyranosyl moieties. Gal..beta..(1..-->..4)GlcNAc-..beta..-hexanolamine was also synthesized in a solid-phase system in which the GlcNAc-..beta..-hexanolamine glycoside was covalently linked to agarose beads. At pH 7.0 and at 1 to 5 mM Mn/sup 2 + +/ the yields of the galactosyl saccharides are greater than 90% by using 10% excess of UDPGal donor. The use of a 90% enriched (1-/sup 13/C)galactosyl residue allowed the determination of the most abundant conformer about the galactopyranosyl-glycoside linkage by analysis of ...

1980-02-05

148

Effect of steric hindrance on carbon dioxide absorption into new amine solutions. Thermodynamic and spectroscopic verification through solubility and NMR analysis  

Energy Technology Data Exchange (ETDEWEB)

Aqueous solutions of 2-amino-2-hydroxymethyl-1,3-propanediol (AHPD), a sterically hindered amine, was examined as a potential CO{sub 2} absorbent and compared with the most commonly used absorbent, monoethanolamine (MEA) solution, through equilibrium solubility measurements and {sup 13}C NMR spectroscopic analyses. The solubilities of CO{sub 2} in aqueous 10 mass % AHPD solutions were higher than those in aqueous 10 mass% MEA solutions above 4 kPa at 298.15 K, but lower below 4 kPa. The solubility difference between these two solutions increased with the CO{sub 2} partial pressures above the crossover pressure. Equilibrated CO{sub 2}-MEA-H{sub 2}O and CO{sub 2}-AHPD-H{sub 2} solutions at various CO{sub 2} partial pressures ranging from 0.01 to 3000 kPa were analyzed by {sup 13}C NMR spectroscopy. AHPD contains more hydroxyl groups than nonhindered MEA, and hence the chemical shifts in its {sup ...

2003-04-15

149

Yeast ribosomal protein L1 is required for the stability of newly synthesized 5S rRNA and the assembly of 60S ribosomal subunits.  

UK PubMed Central (United Kingdom)

Ribosomal protein L1 from Saccharomyces cerevisiae binds 5S rRNA and can be released from intact 60S ribosomal subunits as an L1-5S ribonucleoprotein (RNP) particle. To understand the nature of the...Full Text Available

1993-05-01

150

Unusual heterogeneity of the 5'-termini of human adenovirus type 2 early region E2 mRNA.  

UK PubMed Central (United Kingdom)

The 5'-terminal structures of human adenovirus type 2 (Ad2) early region 2 (E2) mRNA were investigated. The E2 transcription unit has several interesting properties, including the presence of a TATA-like...Full Text Available

1984-12-11

151

The human U1-70K snRNP protein: cDNA cloning, chromosomal localization, expression, alternative splicing and RNA-binding.  

UK PubMed Central (United Kingdom)

We have isolated and sequenced cDNA clones encoding the human U1-70K snRNP protein, and have mapped this locus (U1AP1) to human chromosome 19. The gene produces two size classes of RNA, a major 1.7-kb...Full Text Available

1987-12-23

152

The distribution of active RNA polymerase II along the transcribed region is gene-specific and controlled by elongation factors  

UK PubMed Central (United Kingdom)

In order to study the intragenic profiles of active transcription, we determined the relative levels of active RNA polymerase II present at the 3′- and 5′-ends of 261 yeast genes by...Full Text Available

2010-08-01

153

The complete sequence of a full length cDNA for human liver glyceraldehyde-3-phosphate dehydrogenase: evidence for multiple mRNA species.  

UK PubMed Central (United Kingdom)

A recombinant M13 clone (O42) containing a 65 b.p. cDNA fragment from human fetal liver mRNA coding for glyceraldehyde-3-phosphate dehydrogenase has been identified and it has been used to isolate from...Full Text Available

1984-12-11

154

The Me31B DEAD-Box Helicase Localizes to Postsynaptic Foci and Regulates Expression of a CaMKII Reporter mRNA in Dendrites of Drosophila Olfactory Projection Neurons  

UK PubMed Central (United Kingdom)

mRNP granules at adult central synapses are postulated to regulate local mRNA translation and synapse plasticity. However, they are very poorly characterized in vivo. Here, in Drosophila...Full Text Available

155

The DNA and RNA specificity of eilatin Ru(II) complexes as compared to eilatin and ethidium bromide  

UK PubMed Central (United Kingdom)

Eilatin-containing ruthenium complexes bind to a broad range of different nucleic acids including: calf thymus (CT) DNA, tRNAPhe, polymeric RNAs and DNAs, and viral RNAs including the HIV-1...Full Text Available

2003-10-01

156

Simultaneous Detection of Multiplex-Amplified Human Immunodeficiency Virus Type 1 RNA, Hepatitis C Virus RNA, and Hepatitis B Virus DNA Using a Flow Cytometer Microsphere-Based Hybridization Assay  

UK PubMed Central (United Kingdom)

The feasibility of performing a multiplex assay for the detection of human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) RNAs and hepatitis B virus (HBV) DNA is demonstrated. This...Full Text Available

2000-03-01

157

Regulation of the mRNA for monocyte-derived neutrophil-activating peptide in differentiating HL60 promyelocytes.  

UK PubMed Central (United Kingdom)

A cDNA library was constructed from HL60 human promyelocyte poly(A)+ RNA harvested 3 h after induction of macrophage differentiation with 12-O-tetradecanoyl phorbol-13-acetate in the presence of cycloheximide....Full Text Available

1989-05-01

158

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

UK PubMed Central (United Kingdom)

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

159

Individual products of the adenovirus 12S and 13S EIa mRNAs stimulate viral EIIa and EIII expression at the transcriptional level.  

UK PubMed Central (United Kingdom)

Recombinant plasmids containing mutant or wild-type adenovirus serotype 2 EIa genes that produce the 12S mRNA alone, the 13S mRNA alone, or both mRNAs were cotransfected into HeLa cells with plasmids...Full Text Available

1984-07-01

160

Identification of physochemical factors controlling the capacity of nano-particles to penetrate cells of the respiratory epithelium  

Environmental Research Database

Objectives1) To establish a protocol for transfection of immortalised type I cells with SiRNA and its effect on cell viability; 2) To optimise silencing of genes involved in endocystosis using SiRNA and confirm successful transfection with western blotting; 3) To investigate the effect of gene silencing on uptake of flourescently-labelled latex nanoparticles.DescriptionTo investigate the mechanisms of particle uptake.

2009-01-31

161

Highly efficient gene silencing using perfect complementary artificial miRNA targeting AP1 or heteromeric artificial miRNA targeting AP1 and CAL genes  

UK PubMed Central (United Kingdom)

Gene silencing is a useful technique for elucidating biological function of genes by knocking down their expression. A recently developed artificial microRNAs (amiRNAs) exploits an endogenous...Full Text Available

2009-03-01

162

Green tea increases anti-inflammatory tristetraprolin and decreases pro-inflammatory tumor necrosis factor mRNA levels in rats  

UK PubMed Central (United Kingdom)

BackgroundTristetraprolin (TTP/ZFP36) family proteins have anti-inflammatory activity by binding to and destabilizing pro-inflammatory mRNAs such as Tnf mRNA, and represent a potential...Full Text Available

163

Genome-wide analysis reveals rapid and dynamic changes in miRNA and siRNA sequence and expression during ovule and fiber development in allotetraploid cotton (Gossypium hirsutum L.)  

UK PubMed Central (United Kingdom)

BackgroundCotton fiber development undergoes rapid and dynamic changes in a single cell type, from fiber initiation, elongation, primary and secondary wall biosynthesis, to fiber...Full Text Available

2009-01-01

164

Evolutionary Constraints Acting on DDX3X Protein Potentially Interferes with Rev-Mediated Nuclear Export of HIV-1 RNA  

UK PubMed Central (United Kingdom)

Differential host-pathogen interactions direct viral replication in infected cells. In HIV-1 infected cells, nuclear export of viral RNA transcripts into cellular cytoplasm is governed by interaction...Full Text Available

165

Enhanced anti-tumor effects of combined MDR1 RNA interference and human sodium/iodide symporter (NIS) radioiodine gene therapy using an adenoviral system in a colon cancer model  

UK PubMed Central (United Kingdom)

Using an adenoviral system as a delivery mediator of therapeutic gene, we investigated the therapeutic effects of the use of combined MDR1 shRNA and human NIS (hNIS)...Full Text Available

2010-07-01

166

Elimination of L-A double-stranded RNA virus of Saccharomyces cerevisiae by expression of gag and gag-pol from an L-A cDNA clone.  

UK PubMed Central (United Kingdom)

We report that expression of a nearly full-length cDNA clone of the L-A double-stranded RNA virus causes virus loss in a wild-type strain of Saccharomyces cerevisiae. We show that in this system exclusion...Full Text Available

1993-05-01

167

Distribution and threshold expression of the tRNA(Lys) mutation in skeletal muscle of patients with myoclonic epilepsy and ragged-red fibers (MERRF).  

UK PubMed Central (United Kingdom)

We investigated the distribution and expression of mutant mtDNAs carrying the A-to-G mutation at position 8344 in the tRNA(Lys) gene in the skeletal muscle of four patients with myoclonus epilepsy and...Full Text Available

1992-12-01

168

Different genetic requirements for anterior RNA localization revealed by the distribution of Adducin-like transcripts during Drosophila oogenesis.  

UK PubMed Central (United Kingdom)

The proteins encoded by polar-localized mRNAs play an important role in cell fate specification along the anteroposterior axis of the Drosophila embryo. The only maternally synthesized mRNA known previously...Full Text Available

1993-03-15

169

Deriving four functional anti-HIV siRNAs from a single Pol III-generated transcript comprising two adjacent long hairpin RNA precursors  

UK PubMed Central (United Kingdom)

Several different approaches exist to generate expressed RNA interference (RNAi) precursors for multiple target inhibition, a strategy referred to as combinatorial (co)RNAi. One such approach makes...Full Text Available

2010-10-01

170

Attenuation of oxidant-induced lung injury by 21-aminosteroids (lazaroids): correlation with the mRNA expression for E-selectin, P-selectin, ICAM-1, and VCAM-1.  

UK PubMed Central (United Kingdom)

We compared the effects of treatment with methylprednisolone or the 21-aminosteroids, U-74389 and U-74006F (Tirilizad mesylate), on hyperoxic lung injury and the associated expression of mRNA for several...Full Text Available

1994-12-01

171

Affinity labelling of ribosomes from the livers of different vertebrates by 2-nitro-4-azidobenzoyl-Phe-tRNA  

International Nuclear Information System (INIS)

Ribosomal protein L 10 from the livers of trout, hen, and rat was found to be the main target for 2-nitro-4-azidobenzoyl-Phe-tRNA in affinity labelling experiments. Therefore, despite somewhat different electrophoretic mobilities, this protein seems to be involved in the organization of the peptidyl transferase centre in ribosomes of various vertebrates. (author).

172

Adenine and guanine recognition of stop codon is mediated by different N domain conformations of translation termination factor eRF1  

UK PubMed Central (United Kingdom)

Positioning of release factor eRF1 toward adenines and the ribose-phosphate backbone of the UAAA stop signal in the ribosomal decoding site was studied using messenger RNA (mRNA) analogs containing...Full Text Available

2011-09-01

173

A bioinformatics tool for linking gene expression profiling results with public databases of microRNA target predictions  

UK PubMed Central (United Kingdom)

MicroRNAs are short (∼22 nucleotides) noncoding RNAs that regulate the stability and translation of mRNA targets. A number of computational algorithms have been developed to help predict which...Full Text Available

2008-11-01

174

4.5S RNA is encoded by hundreds of tandemly linked genes, has a short half-life, and is hydrogen bonded in vivo to poly(A)-terminated RNAs in the cytoplasm of cultured mouse cells.  

UK PubMed Central (United Kingdom)

4.5S RNA is a group of RNAs 90 to 94 nucleotides long (length polymorphism due to a varying number of UMP residues at the 3' end) that form hydrogen bonds with poly(A)-terminated RNAs isolated from...Full Text Available

1986-05-01

175

Stability and cations coordination of DNA and RNA 14-mer G-quadruplexes: a multiscale computational approach.  

Science.gov (United States)

Molecular dynamics simulations have been used to study the differences between two DNA and RNA 14-mer quadruplexes of analogous sequences. Their structures present a completely different fold: DNA forms a bimolecular quadruplex containing antiparallel strands and diagonal loops; RNA forms an intrastrand parallel quadruplex containing a G-tetrad and an hexad, which dimerizes by hexad stacking. We used a multiscale computational approach combining classical Molecular dynamics simulations and density functional theory calculations to elucidate the difference in stability of the 2-folds and their ability in coordinating cations. The presence of 2'-OH groups in the RNA promotes the formation of a large number of intramolecular hydrogen bonds that account for the difference in fold and stability of the two 14-mers. We observe that the adenines in the RNA quadruplex play a key role in conserving the geometry ...

2008-09-03

176

Inhibition of glypican-3 expression via RNA interference influences the growth and invasive ability of the MHCC97-H human hepatocellular carcinoma cell line.  

Science.gov (United States)

Glypican-3 (GPC3), a membrane-bound heparan sulfate proteoglycan, is found to be overexpressed in hepatocellular carcinoma (HCC). The purpose of the present study was to investigate the possible role of GPC3 in the development of HCC. In this study, RNA interference (RNAi) with a GPC3 small hairpin RNA (GPC3 shRNA) was used to identify the effects of GPC3 on the regulation of malignant behaviors of HCC. MHCC97-H, a highly metastatic human HCC cell line in which GPC3 mRNA and protein levels were detected as the highest among the 4 HCC cell lines assessed in this study, and was thus selected as a cell model for in vitro and in vivo experiments. The results showed that down-regulation of GPC3 can significantly inhibit the proliferative and invasive ability of MHCC97-H. Compared with the parental HCC cells, GPC3-silenced cells exhibited attenuated capacities in developing tumors in nude mice, while the ...

2011-05-20

177

Cotton plants expressing CYP6AE14 double-stranded RNA show enhanced resistance to bollworms  

British Library Electronic Table of Contents (United Kingdom)

RNA interference (RNAi) plays an important role in regulating gene expression in eukaryotes. Previously, we generated Arabidopsis and tobacco plants expressing double-stranded RNA (dsRNA) targeting a cotton bollworm (Helicoverpa armigera) P450 gene, CYP6AE14. Bollworms fed on transgenic dsCYP6AE14 plants showed suppressed CYP6AE14 expression and reduced growth on gossypol-containing diet (Mao et?al., in Nat Biotechnol 25: 1307?1313, 2007). Here we report generation and analysis of dsRNA-expressing cotton (Gossypium hirsutum) plants. Bollworm larvae reared on T2 plants of the ds6-3 line exhibited drastically retarded growth, and the transgenic plants were less damaged by bollworms than the control. Quantitative reverse-transcription polymerase chain reaction (RT-PCR) showed that the CYP6AE1...

2011-01-01

178

Evolution of Hox Post-Transcriptional Regulation by Alternative Polyadenylation and MicroRNA Modulation Within 12 Drosophila Genomes.  

Science.gov (United States)

Hox genes encode a family of transcriptional regulators that operate differential developmental programs along the anteroposterior axis of bilateral animals. Regulatory changes affecting Hox gene expression are believed to have been crucial for the evolution of animal body plans. In Drosophila melanogaster, Hox expression is post-transcriptionally regulated by microRNAs (miRNAs) acting on target sites located in the 3' untranslated regions (3'UTRs) of Hox mRNAs. Notably, recent work has shown that during D. melanogaster development Hox genes produce mRNAs with variable 3'UTRs (short and long forms) in different sets of tissues as a result of alternative polyadenylation; importantly, Hox short and long 3'UTRs contain very different target sites for miRNAs. Here, we use a computational approach to explore the evolution of Hox 3'UTRs treated with especial regard to miRNA regulation. Our work is focused on the 12 Drosophila species for which genomic sequences are ...

2011-03-24

179

Isotope labeling strategies for NMR studies of RNA  

Energy Technology Data Exchange (ETDEWEB)

The known biological functions of RNA have expanded in recent years and now include gene regulation, maintenance of sub-cellular structure, and catalysis, in addition to propagation of genetic information. As for proteins, RNA function is tightly correlated with structure. Unlike proteins, structural information for larger, biologically functional RNAs is relatively limited. NMR signal degeneracy, relaxation problems, and a paucity of long-range {sup 1}H-{sup 1}H dipolar contacts have limited the utility of traditional NMR approaches. Selective isotope labeling, including nucleotide-specific and segmental labeling strategies, may provide the best opportunities for obtaining structural information by NMR. Here we review methods that have been developed for preparing and purifying isotopically labeled RNAs, as well as NMR strategies that have been employed for signal assignment and structure determination.

2010-01-15

180

Two dimensional NMR and NMR relaxation studies of coal structure  

Energy Technology Data Exchange (ETDEWEB)

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with [sup 13]C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed at delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.

1992-11-25

181

Steady-state isotopic transient kinetic analysis investigation of CO-O_2 and CO-NO reactions over a commercial automotive catalyst  

International Nuclear Information System (INIS)

In this paper, steady-state isotopic transient kinetic analysis (SSITKA) is used to study two model reactions, CO oxidation and CO-NO reactions, on a typical formulation of a three-way auto-catalyst. Under steady-state conditions, abrupt switches in the isotopic composition of CO ("1"2C"1"6O/"1"3C"1"8O) were carried out to produce isotopic transients in both labeled reactants and products. Along with the determination of the average surface lifetimes and concentrations of reaction intermediates, an analysis of the transient responses along the carbon reaction pathway indicated that the distribution of active sites for the formation of CO_2 was bimodal for both reactions. Furthermore, relatively few surface sites contributed to the overall reaction rate.

1991-08-25

182

Polyester and multiwalled carbon nanotube composites: characterization, electrical conductivity and antibacterial activity  

British Library Electronic Table of Contents (United Kingdom)

Abstract Poly(butylene terephthalate) (PBT) composites containing multiwalled carbon nanotubes (MWCNTs) were prepared using a melt-blending process and used to examine the effects on the composite structure and properties of replacing PBT with acrylic acid-grafted PBT (PBT-g-AA). PBT-g-AA and multihydroxyl-functionalized MWCNTs (MWCNTs-OH) were used to improve the compatibility and dispersibility of the MWCNTs within the PBT matrix. The composites were characterized morphologically using transmission electron microscopy, and chemically using Fourier transform infrared, solid-state 13C NMR and UV-visible absorption spectroscopy. The antibacterial and electrical conductivity properties of the composites were also evaluated. MWCNTs or MWCNTs-OH enhanced the antibacterial activity and electric...

2011-01-01

183

Patagonicosides B and C, two antifungal sulfated triterpene glycosides from the sea cucumber Psolus patagonicus.  

Science.gov (United States)

Two new triterpene glycosides, patagonicosides B and C (2 and 3, resp.), together with the known patagonicoside A (1), have been isolated from the EtOH extract of the sea cucumber Psolus patagonicus. The structures of the new compounds were established on the basis of extensive NMR spectroscopic analysis ((1)H- and (13)C-NMR, (1)H,(1)H-COSY, HMBC, HSQC, TOCSY, and NOESY), HR-ESI-MS data, and chemical transformations. Compounds 1-3 and their desulfated analogs showed antifungal activities against the phytopathogenic fungus Cladosporium cladosporoides in a dose-dependent fashion. PMID:21404430

2011-03-01

184

Magic-angle-spinning NMR studies of acid sites in zeolite H-ZSM-5  

Science.gov (United States)

{sup 1}H, {sup 13}C, {sup 27}Al, and {sup 29}Si magic-angle-spinning (MAS) NMR was used to elucidate the nature of the catalytic activity of zeolite H-ZSM-5. {sup 1}H MAS NMR of sealed samples after mild hydrothermal dealumination shows that the enhanced activity for n-hexane cracking is not due to an enhanced Bronstead acidity. The concentrations of the various OH groups and aluminous species suggest that the reason for the enhanced catalytic activity is the interaction of the n-hexane molecule with a bridging hydroxyl group and with extra-framework aluminium species, which give rise to the enhanced activity, cannot be easily removed from their positions, and are therefore immobilized by the zeolitic framework.

1991-01-01

185

Fullerene-Derivatized Amino Acids: Synthesis, Characterization, Antioxidant Properties, and Solid-Phase Peptide Synthesis  

British Library Electronic Table of Contents (United Kingdom)

A series of [60]fullerene-substituted phenylalanine (Baa) and lysine derivatives have been prepared by the condensation of 1,2-(4prime-oxocyclohexano)fullerene with the appropriately protected (4-amino)phenylalanine and lysine, respectively. Conversion of the imine to the corresponding amine is achieved by di-acid catalyzed hydroboration. The reduction of the imine is not accompanied by hydroboration of the fullerene cage. The [70]fullerene phenylalanine derivative has also been prepared as have the di-amino acid derivatives. The compounds were characterized by MALDI-TOF mass spectrometry, UV/Vis spectroscopy, and cyclic voltammetry. 1H and 13C NMR spectroscopy allowed the observation of diastereomers. Fullerene-substituted peptides may be synthesized on relatively large scale by solid-pha...

2007-01-01

186

Five naturally bioactive molecules including two rhamnopyranoside derivatives isolated from the Streptomyces sp. strain TN58  

British Library Electronic Table of Contents (United Kingdom)

Extraction of 25 L fermentation broth of the newly isolated Streptomyces sp. strain TN58 and various separation and purification steps led to the isolation of five bioactive metabolites, namely brevianamide F (C1), reported from a streptomycete for the first time, N?-acetyltryptamine (C2), thiazolidomycin (C3), and two rhamnopyranosides (C4 and C5). These two rhamnopyranosides were produced directly, without precursor addition. The chemical structure of these five active compounds was established on the basis of 1H, 13C/APT and 2D NMR spectra, ESI and EI-MS data, and by comparison with data from the literature. According to the biological studies, we show in this work that the compounds C1, C2, C4 and C5 possess antimicrobial activities.

2009-01-01

187

Evaluation of gels obtained from acetylation of chitosan in heterogeneous medium  

International Nuclear Information System (INIS)

Chitosan was acetylated during 2, 5 and 10 h and physical gels were obtained at different polymer concentrations in N,N-dimethylacetamide containing 5% of LiCl. Acetylation was confirmed by infrared spectroscopy and "1"3C NMR, and degrees of acetylation in the range of 0.82-0.91 were determined by NMR. The O-acetylation degree (0.12-0.15) was exclusively determined by a volumetric method. Rheological studies showed that the storage modulus values were smaller for the more acetylated samples and increased with the temperature and the polymer concentration. All the gels presented storage modulus superior to loss modulus, evidencing more elastic than viscous characteristics. The results obtained in this work suggest a gelation process based on a balance between O and N-acetylation and intermolecular bonds. (author)

188

Endophytic fungus Trichothecium roseum LZ93 antagonizing pathogenic fungi in vitro and its secondary metabolites  

British Library Electronic Table of Contents (United Kingdom)

The endophytic fungus Trichothecium roseum LZ93 from Maytenus hookeri was found to antagonize other pathogenic fungi in vitro. To identify which compound contributed substantially to the antagonism, we fermented the strain and purified its fermentation products. Eleven compounds were obtained, including two trichothecenes, five rosenonolactones, two cardiotonic cyclodepsipeptides, and two sterols. Compound 11?-hydroxyrosenonolactone (1) was assigned according to 1D and 2D-NMR data for the first time. At the same time, the 1H and 13C-NMR assignments for 6?-hydroxyrosenonolactone (2) were revised. Of all of them, only trichothecin (6) showed strong antifungal activity. Based on our observations of the antagonistic activity and the other experimental results, we suggest that the antifungal co...

2010-01-01

189

Elastic and inelastic scattering of "1"4C from medium heavy nuclei  

International Nuclear Information System (INIS)

The elastic and inelastic scattering of "1"4C at 51 MeV from targets of "4"0Ca, "5"6Fe, "6"0Ni, "6"6Zn and "8"8Sr has been measured using a Q3D spectrometer. The "1"4C-nucleus potentials have been derived by optical-model analysis of the observed elastic scattering; the inelastic scattering differential cross sections were interpreted in the distorted-wave Born approximation and also in the coupled-channels approach. The analysis yields "1"4C-nucleus potentials that closely resemble "1"2sup(,)"1"3C and "1"6O potentials. (orig.).

190

Cationic cyclization of purified natural rubber in latex form with a trimethylsilyl triflate as a novel catalyst  

British Library Electronic Table of Contents (United Kingdom)

Cyclization of deproteinized natural rubber (DPNR) or purified natural rubber latex was effectively performed in latex phase by using trimethylsilyl-trifluoromethane sulfonate or trimethylsilyl triflate (TMSOTF) as a novel catalyst, which is still not reported in the case of natural rubber latex. Various cyclization conditions affecting the degree of cyclization were studied, such as dry rubber contents, temperature, TMSOTF concentrations, and time. The cyclized products were characterized by FTIR, Raman, 1H-, and 13C-NMR spectroscopies, as well as DSC and TGA. The degree of cyclization was estimated by 1H-NMR spectrum. It was found that the degree of cyclization in NR was a function of cyclization conditions. The thermal stability of cyclized DPNR increased with the degree of cyclization....

2007-01-01

191

A new vanadium Schiff base complex as catalyst for oxidation of alcohols  

British Library Electronic Table of Contents (United Kingdom)

The monoanionic bidentate Schiff base, N-(phenolyl)-benzaldimine (HL), has been employed to synthesize a new vanadium(IV) complex of general composition [VO(L)2] (where L = O, N donor of Schiff base). The ligand and complex have been fully characterized by elemental analyses, molar conductance data, FT-IR, 1H- and 13C-NMR, and UV-Vis spectroscopies. Oxidation of alcohols to their corresponding aldehydes and ketones was conducted by this complex catalyst using Oxone as oxidant under biphasic reaction conditions (CH2Cl2/H2O) and tetra-n-butylammonium bromide as phase transfer agent under air at room temperature.

2010-01-01

192

YAPI, a New Yersinia pseudotuberculosis Pathogenicity Island  

UK PubMed Central (United Kingdom)

Pathogenicity islands (PAIs) are chromosomal clusters of pathogen-specific virulence genes often found at tRNA loci. In the Yersinia pseudotuberculosis 32777 chromosome, we characterized...Full Text Available

2004-08-01

193

Worlds within worlds: evolution of the vertebrate gut microbiota  

UK PubMed Central (United Kingdom)

Here we use published 16S rRNA gene sequences to compare the bacterial assemblages associated with humans, other mammals, other metazoa, and free-living microbial communities spanning a range...Full Text Available

2008-10-01

194

Use of synthetic oligoribonucleotides to probe RNA-protein interactions in the MS2 translational operator complex.  

UK PubMed Central (United Kingdom)

Synthetic oligoribonucleotides have been used to probe the interaction of MS2 coat protein with the translational operator of the MS2 replicase gene. We have investigated the possible formation of a...Full Text Available

1990-06-25

195

Use of synthetic oligonucleotide DNA probes for identification and direct detection of Bacteroides forsythus in plaque samples.  

UK PubMed Central (United Kingdom)

Oligonucleotide DNA probes complementary to the hypervariable region of the 16S rRNA of Bacteroides forsythus were tested for their specificity and sensitivity against reference and clinical isolates...Full Text Available

1991-10-01

196

Two separate domains within vesicular stomatitis virus phosphoprotein support transcription when added in trans.  

UK PubMed Central (United Kingdom)

The structural phosphoprotein NS of vesicular stomatitis virus, in association with the virion-associated RNA polymerase L protein, transcribes the genome ribonucleoprotein template in vitro. It contains...Full Text Available

1987-12-01

197

Two Proline-Rich Nuclear Localization Signals in the Amino- and Carboxyl-Terminal Regions of the Borna Disease Virus Phosphoprotein  

UK PubMed Central (United Kingdom)

Borna disease virus (BDV) uses a unique strategy of replication and transcription which takes place in the nucleus, unlike other known, nonsegmented, negative-stranded RNA viruses of animal origin....Full Text Available

1998-12-01

198

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

UK PubMed Central (United Kingdom)

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

199

Towards computational prediction of microRNA function and activity  

UK PubMed Central (United Kingdom)

While it has been established that microRNAs (miRNAs) play key roles throughout development and are dysregulated in many human pathologies, the specific processes and pathways regulated by individual...Full Text Available

2010-08-01

200

Time course profiling of the retinal transcriptome after optic nerve transection and optic nerve crush  

UK PubMed Central (United Kingdom)

PurposeA time-course analysis of gene regulation in the adult rat retina after intraorbital nerve crush (IONC) and intraorbital nerve transection (IONT).MethodsRNA...Full Text Available

201

Synaptic Signaling and Aberrant RNA Splicing in Autism Spectrum Disorders  

UK PubMed Central (United Kingdom)

Interactions between presynaptic and postsynaptic cellular adhesion molecules (CAMs) drive synapse maturation during development. These trans-synaptic interactions are regulated by alternative splicing...Full Text Available

202

Subcellular Localization of Expansin mRNA in Xylem Cells12  

UK PubMed Central (United Kingdom)

Terminal differentiation of many vascular cells involves cell wall changes. Cells first elongate their primary wall, then lay down a lignified secondary wall, which is often followed by digestion of...Full Text Available

2000-06-01

203

Species-specific microRNA roles elucidated following astrocyte activation  

UK PubMed Central (United Kingdom)

MicroRNAs (miRNAs) are short non-coding RNAs that play a central role in regulation of gene expression by binding to target genes. Many miRNAs were associated with the function of the central nervous...Full Text Available

2011-05-01

204

Slug down-regulation by RNA interference inhibits invasion growth in human esophageal squamous cell carcinoma  

UK PubMed Central (United Kingdom)

BackgroundEsophageal squamous cell carcinoma (ESCC) is one of the most aggressive carcinomas of the gastrointestinal tract. We assessed the relevance of Slug in measuring the invasive...Full Text Available

205

Selective Degradation of Newly Synthesized Nonmessenger Simian Virus 40 Transcripts  

UK PubMed Central (United Kingdom)

By pretreating simian virus 40-infected BSC-1 cells with glucosamine, [3H]uridine labeling of both cellular and viral RNA can be halted instantaneously by addition of cold uridine. We have...Full Text Available

1978-11-01

206

Seasonal and Spatial Variability of Bacterial and Archaeal Assemblages in the Coastal Waters near Anvers Island, Antarctica  

UK PubMed Central (United Kingdom)

A previous report of high levels of members of the domain Archaea in Antarctic coastal waters prompted us to investigate the ecology of Antarctic planktonic prokaryotes. rRNA hybridization...Full Text Available

1998-07-01

207

SWISS MADE: Standardized WithIn Class Sum of Squares to Evaluate Methodologies and Dataset Elements  

UK PubMed Central (United Kingdom)

Contemporary high dimensional biological assays, such as mRNA expression microarrays, regularly involve multiple data processing steps, such as experimental processing, computational processing, sample...Full Text Available

208

Role of microRNA-23b in flow-regulation of Rb phosphorylation and endothelial cell growth  

UK PubMed Central (United Kingdom)

MicroRNAs (miRs) can regulate many cellular functions, but their roles in regulating responses of vascular endothelial cells (ECs) to mechanical stimuli remain unexplored. We hypothesize that the physiological...Full Text Available

2010-02-16

209

RNA:DNA Ratio and Other Nucleic Acid Derived Indices in Marine Ecology  

UK PubMed Central (United Kingdom)

Some of most used indicators in marine ecology are nucleic acid-derived indices. They can be divided by target levels in three groups: 1) at the organism level as ecophysiologic indicators, indicators...Full Text Available

210

RNA recognition by the embryonic cell fate determinant and germline totipotency factor MEX-3  

UK PubMed Central (United Kingdom)

Totipotent stem cells have the potential to differentiate into every cell type. Renewal of totipotent stem cells in the germline and cellular differentiation during early embryogenesis rely upon posttranscriptional...Full Text Available

2009-12-01

211

RNA expression in a cartilaginous fish cell line reveals ancient 3? noncoding regions highly conserved in vertebrates  

UK PubMed Central (United Kingdom)

We have established a cartilaginous fish cell line [Squalus acanthias embryo cell line (SAE)], a mesenchymal stem cell line derived from the embryo of an elasmobranch, the spiny dogfish...Full Text Available

2007-01-23

212

Profiling highly conserved microrna expression in recombinant IgG-producing and parental Chinese hamster ovary cells  

British Library Electronic Table of Contents (United Kingdom)

Abstract MicroRNAs (miRNAs) play important roles in global gene regulation. Researchers in recombinant protein production have proposed miRNAs as biomarkers and cell engineering targets. However, miRNA expression remains understudied in Chinese Hamster Ovary cells, one of the most commonly used host cell systems for therapeutic protein production. To profile highly conserved miRNA expression, we used the miRCURY- miRNA array for screening miRNAs in CHO cells. The selection criteria for further miRNA profiling included positive hybridization signals and experimentally validated predicted regulatory targets. On the basis of screening, we selected 16 miRNAs for quantitative RT-PCR profiling. We profiled miR expression in parental CHO DG44 and CHO K1 cell lines as well as four recombinant DG44...

2011-01-01

213

Production of dissolved DNA, RNA, and protein by microbial populations in a Florida reservoir.  

UK PubMed Central (United Kingdom)

Production of dissolved macromolecules by ambient autotrophic and heterotrophic microbial populations was measured in a eutrophic Florida reservoir by in situ labeling with various radioactive substrates....Full Text Available

1990-10-01

214

Polymorphisms in IRF7 reduce IFN? responses of pDCs to HIV-1  

UK PubMed Central (United Kingdom)

Recognition of HIV-1 ssRNA by TLR7 induces the production of the pro-inflammatory cytokines that may contribute to the systemic immune activation associated with HIV-1 disease progression. Here...Full Text Available

2011-03-13

215

Perinuclear P granules are the principal sites of mRNA export in adult C. elegans germ cells  

UK PubMed Central (United Kingdom)

Germline-specific granules of unknown function are found in a wide variety of organisms, including C. elegans, where they are called P granules. P granules are cytoplasmic bodies...Full Text Available

2010-04-15

216

PCR-based method for targeting 16S-23S rRNA intergenic spacer regions among Vibrio species  

UK PubMed Central (United Kingdom)

BackgroundThe genus Vibrio is a diverse group of Gram-negative bacteria comprised of 74 species. Furthermore, the genus has and is expected to continue expanding...Full Text Available

217

Northern blotting analysis of microRNAs, their precursors and RNA interference triggers  

UK PubMed Central (United Kingdom)

BackgroundNumerous microRNAs (miRNAs) have heterogeneous ends resulting from imprecise cleavages by processing nucleases and from various non-templated nucleotide additions. The...Full Text Available

218

NASA/CR--- _'j_.,- 207636 - NASA Technical Report Server (NTRS)  

Science.gov (United States)

adenines, like adenine itself, may fllerefore have played an important role in the. RNA world. Griffin, B.E., Haslam, W.J., Reese, C. B.: 1964, J. Mo/. ...

219

Modulation of the human hair follicle pigmentary unit by corticotropin-releasing hormone and urocortin peptides  

UK PubMed Central (United Kingdom)

Human skin is a local source of corticotropin-releasing hormone (CRH) and expresses CRH and CRH receptors (CRH-R) at mRNA and protein levels. Epidermal melanocytes respond to CRH by induction...Full Text Available

2006-05-01

220

Modeling RNA polymerase competition: the effect of ?-subunit knockout and heat shock on gene transcription level  

UK PubMed Central (United Kingdom)

BackgroundModeling of a complex biological process can explain the results of experimental studies and help predict its characteristics. Among such processes is transcription in...Full Text Available

221

Miranda as a multidomain adapter linking apically localized Inscuteable and basally localized Staufen and Prospero during asymmetric cell division in Drosophila  

UK PubMed Central (United Kingdom)

Neuroblasts in the developing Drosophila CNS asymmetrically localize the cell fate determinants Numb and Prospero as well as prospero RNA to the basal cortex during...Full Text Available

1998-06-15

222

MAPPING THE INITIATOR BINDING TAF2 SUBUNIT IN THE STRUCTURE OF HYDRATED YEAST TFIID  

UK PubMed Central (United Kingdom)

SummaryThe general transcription factor TFIID is a large multi-subunit complex required for the transcription of most protein-encoding genes by RNA polymerase II. Taking advantage...Full Text Available

2009-03-11

223

Intact A?-fibers up-regulate TRPA1 and contribute to cold hypersensitivity in neuropathic rats  

UK PubMed Central (United Kingdom)

Mechanisms underlying cold hypersensitivity in neuropathic states are unclear. Recent data indicate both TRPM8 and TRPA1 play a role. In relation to TRPA1, there are reported increases in mRNA....Full Text Available

2008-06-26

224

Insertion in the mRNA of a metachromatic leukodystrophy patient with sphingolipid activator protein-1 deficiency.  

UK PubMed Central (United Kingdom)

The lysosomal catabolism of sulfatide requires arylsulfatase A and a specific sphingolipid activator protein, SAP-1. While most patients with metachromatic leukodystrophy have mutations in the gene...Full Text Available

1990-02-01

225

In vitro selection of RNA molecules that displace cocaine from the membrane-bound nicotinic acetylcholine receptor  

UK PubMed Central (United Kingdom)

The nicotinic acetylcholine receptor (AChR) controls signal transmission between cells in the nervous system. Abused drugs such as cocaine inhibit this receptor. Transient kinetic investigations indicate...Full Text Available

1998-11-24

226

Improved Understanding of the Bacterial Vaginal Microbiota of Women before and after Probiotic Instillation  

UK PubMed Central (United Kingdom)

The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradient gel electrophoresis (DGGE) and sequencing of the V2-V3 region of the 16S rRNA gene. Ten of the women...Full Text Available

2003-01-01

227

Hyperoxia enhances VEGF release from A549 cells via post-transcriptional processes  

UK PubMed Central (United Kingdom)

Exposure of animals to hyperoxia decreases lung VEGF mRNA expression concomitant with an acute increase in VEGF protein within the epithelial lining fluid (ELF). The VEGF concentration in ELF...Full Text Available

2007-09-01

228

Human Immunodeficiency Virus type-1 reverse transcriptase exists as post-translationally modified forms in virions and cells  

UK PubMed Central (United Kingdom)

BackgroundHIV-1 reverse transcriptase (RT) is a heterodimer composed of p66 and p51 subunits and is responsible for reverse transcription of the viral RNA genome into DNA. RT can...Full Text Available

229

General lack of global dosage compensation in ZZ/ZW systems? Broadening the perspective with RNA-seq  

UK PubMed Central (United Kingdom)

BackgroundSpecies with heteromorphic sex chromosomes face the challenge of large-scale imbalance in gene dose. Microarray-based studies in several independent male heterogametic...Full Text Available

230

Gene expression analysis of interferon ? in laser capture microdissected cervical epithelium  

UK PubMed Central (United Kingdom)

Optimal sample handling techniques for tissue preparation and storage, RNA extraction and quantification, and target gene detection are crucial for reliable gene expression analysis. Methods...Full Text Available

2008-10-01

231

Expression profiles of precursor and mature microRNAs under dehydration and high salinity shock in Populus euphratica  

British Library Electronic Table of Contents (United Kingdom)

MicroRNAs (miRNAs) are small non-coding RNAs that play vital roles in plant abiotic stress responses via cleavage or translational inhibition of their target mRNAs. Populus euphratica is a typical stress-resistant sessile organism that grows in desert areas. Here, we identified sequences of 12 miRNA precursors from 11 families and 13 mature miRNAs from 12 families by PCR amplification in P. euphratica. To detect expression differences in mature miRNAs and their precursors under dehydration and high salinity shock in P. euphratica, we examined 14 miRNA precursors from 13 miRNA families and 17 mature miRNAs from 17 miRNA families using the SYBR Green RT?PCR assay. This is the first report of expression profiles for both precursor and mature miRNAs in P. euphratica. By profiling both the matu...

2011-01-01

232

Euryarchaeal ?-CASP Proteins with Homology to Bacterial RNase J Have 5?- to 3?-Exoribonuclease Activity*  

UK PubMed Central (United Kingdom)

In the Archaea only a handful of ribonucleases involved in RNA processing and degradation have been characterized. One potential group of archaeal ribonucleases are homologues of the bacterial RNase...Full Text Available

2010-06-04

233

Engineering ligand-responsive RNA controllers in yeast through the assembly of RNase III tuning modules  

UK PubMed Central (United Kingdom)

The programming of cellular networks to achieve new biological functions depends on the development of genetic tools that link the presence of a molecular signal to gene-regulatory activity. Recently,...Full Text Available

2011-07-01

234

Effect of hypophysectomy on liver nuclear ribonucleic acid synthesis in aging rats.  

UK PubMed Central (United Kingdom)

Changes in RNA synthesis in liver nuclei were observed at different ages and after hypophysectomy and hormone replacement in female Sprague-Dawley rats. As determined by the incorporation of [3H]UMP...Full Text Available

1979-12-15

235

Ectopic Expression of Constitutively Activated RACB in Barley Enhances Susceptibility to Powdery Mildew and Abiotic Stress1  

UK PubMed Central (United Kingdom)

Small RAC/ROP-family G proteins regulate development and stress responses in plants. Transient overexpression and RNA interference experiments suggested that the barley (Hordeum vulgare)...Full Text Available

2005-09-01

236

Direct Evidence for Postmeiotic Transcription During Drosophila melanogaster Spermatogenesis  

UK PubMed Central (United Kingdom)

Extensive gene expression during meiosis is a hallmark of spermatogenesis. Although it was generally accepted that RNA transcription ceases during meiosis, recent observations suggest that some transcription...Full Text Available

2010-09-01

237

Differential recognition of viral RNA by RIG-I  

UK PubMed Central (United Kingdom)

Retinoic acid inducible gene I (RIG-I) is a pattern recognition receptor (PRR) responsible for detection of nucleic acids from pathogens in the cytoplasm of infected cells and induction of type I interferon...Full Text Available

2011-03-01

238

Detection of Atopobium vaginae in Postmenopausal Women by Cultivation-Independent Methods Warrants Further Investigation  

UK PubMed Central (United Kingdom)

We sequenced 16S rRNA genes from the vaginal swab contents of a postmenopausal woman with asymptomatic bacterial vaginosis (BV). Sequences from Atopobium vaginae were the most commonly...Full Text Available

2004-04-01

239

Defects in the Secretory Pathway and High Ca2+ Induce Multiple P-bodies  

UK PubMed Central (United Kingdom)

mRNA is sequestered and turned over in cytoplasmic processing bodies (PBs), which are induced by various cellular stresses. Unexpectedly, in Saccharomyces cerevisiae, mutants of the...Full Text Available

2010-08-01

240

Defective hepatitis B virus particles are generated by packaging and reverse transcription of spliced viral RNAs in vivo.  

UK PubMed Central (United Kingdom)

Generation of replicative defective viruses is frequently observed during viral infections. We now report that encapsidation and reverse transcription of spliced viral RNA is an additional mechanism...Full Text Available

1991-10-01

241

Conserved Alternative Splicing and Expression Patterns of Arthropod N-Cadherin  

UK PubMed Central (United Kingdom)

Metazoan development requires complex mechanisms to generate cells with diverse function. Alternative splicing of pre-mRNA not only expands proteomic diversity but also provides a means to regulate...Full Text Available

2009-04-01

242

Complexity of the microRNA repertoire revealed by next-generation sequencing  

UK PubMed Central (United Kingdom)

MicroRNAs (miRNAs) have been implicated to play key roles in normal physiological functions, and altered expression of specific miRNAs has been associated with a number of diseases. It is of great interest...Full Text Available

2010-11-01

243

Complete characterization of the edited transcriptome of the mitochondrion of Physarum polycephalum using deep sequencing of RNA  

UK PubMed Central (United Kingdom)

RNAs transcribed from the mitochondrial genome of Physarum polycephalum are heavily edited. The most prevalent editing event is the insertion of single Cs, with Us and dinucleotides...Full Text Available

2011-08-01

244

Comparative genomics reveals 104 candidate structured RNAs from bacteria, archaea, and their metagenomes  

UK PubMed Central (United Kingdom)

BackgroundStructured noncoding RNAs perform many functions that are essential for protein synthesis, RNA processing, and gene regulation. Structured RNAs can be detected by comparative...Full Text Available

2010-01-01

245

Coat protein gene duplication in a filamentous RNA virus of plants.  

UK PubMed Central (United Kingdom)

Computer-assisted analysis revealed a striking sequence similarity between the putative 24-kDa protein (p24) encoded by open reading frame (ORF) 5 of beet yellows closterovirus and the coat protein...Full Text Available

1992-10-01

246

Characterization of the Molecular Mechanism of Defective Interfering RNA-Mediated Symptom Attenuation in Tombusvirus-Infected Plants  

UK PubMed Central (United Kingdom)

Different tombusviruses were able to support the replication of either homologous or heterologous defective interfering (DI) RNAs, and those infected plants usually developed typical attenuated symptoms....Full Text Available

1998-07-01

247

Cbk1 regulation of the RNA binding protein Ssd1 integrates cell fate with translational control  

UK PubMed Central (United Kingdom)

SummarySpatial control of gene expression, at the level of both transcription and translation, is critical for cellular differentiation [1-Full Text Available

2009-12-29

248

Avian Nephritis Virus (ANV) as a New Member of the Family Astroviridae and Construction of Infectious ANV cDNA  

UK PubMed Central (United Kingdom)

The complete RNA genome of the avian nephritis virus (ANV) associated with acute nephritis in chickens has been molecularly cloned and sequenced. Excluding the poly(A) tail, the genome comprises 6,927...Full Text Available

2000-09-01

249

Association of Unique, Isolated Treponemes with Bovine Digital Dermatitis Lesions?  

UK PubMed Central (United Kingdom)

This study used a PCR-based approach targeting 16S rRNA gene fragments to determine the occurrence and association of the three bovine digital dermatitis (BDD) treponeme phylogroups within lesions found...Full Text Available

2009-03-01

250

Assessing phytoremediation potentials of selected tropical plants for acrylamide  

Science.gov (United States)

In biotechnology, acrylamide is being used in DNA and RNA analysis using the polyacrylamide gel electrophoreses procedure. Polymerized acrylamide is degraded into acrylamide through time; it is converted into a hazardous contaminant that is carcinogenic and neurotoxic to animals and humans. Because ...

251

Amber suppression in Escherichia coli by unusual mitochondria-like?transfer?RNAs  

UK PubMed Central (United Kingdom)

The “cloverleaf” base-pairing pattern was established as the structural paradigm of active tRNA species some 30 years ago. Nevertheless, this pattern does not accommodate the folding...Full Text Available

1998-02-17

252

A small RNA promotes siderophore production through transcriptional and metabolic remodeling  

UK PubMed Central (United Kingdom)

Siderophores are essential factors for iron (Fe) acquisition in bacteria during colonization and infection of eukaryotic hosts, which restrain iron access through iron-binding protein, such as lactoferrin...Full Text Available

2010-08-24

253

A retinoid responsive cytokine gene, MK, is preferentially expressed in the proximal tubules of the kidney and human tumor cell lines.  

UK PubMed Central (United Kingdom)

The aim of this study was to survey the expression of an embryonic cytokine gene, MK, in the normal organs and neoplastic tissues of adults. Northern analysis showed that MK mRNA was exclusively expressed...Full Text Available

1993-02-01

254

A T to A base substitution and small deletions in the conalbumin TATA box drastically decrease specific in vitro transcription.  

UK PubMed Central (United Kingdom)

We have previously shown that a T to G transversion at the second T of the conalbumin "TATA" box drastically decreases specific initiation of transcription by RNA polymerase B (1). We now report that...Full Text Available

1981-04-24

255

A Curated Database of miRNA Mediated Feed-Forward Loops Involving MYC as Master Regulator  

UK PubMed Central (United Kingdom)

BackgroundThe MYC transcription factors are known to be involved in the biology of many human cancer types. But little is known about the Myc/microRNAs cooperation in the regulation...Full Text Available

256

A Cellular J-Domain Protein Modulates Polyprotein Processing and Cytopathogenicity of a Pestivirus  

UK PubMed Central (United Kingdom)

Pestiviruses are positive-strand RNA viruses closely related to human hepatitis C virus. Gene expression of these viruses occurs via translation of a polyprotein, which is further processed by cellular...Full Text Available

2001-10-01

257

The nucleotide sequence of a major species of leucine tRNA from bovine liver.  

UK PubMed Central (United Kingdom)

Through the use of a variety of post-labeling techniques, the nucleotide sequence of a major species of leucine tRNA from bovine liver was determined to be pG-G-U-A-G-C-G-U-G-m-G-C-ac-C-G-A-G-C-G-G-D-C-psi-A-A-G-G-C-m-G-C-U-G-G-A-psim-...Full Text Available

1980-02-25

258

The effect of mitochondrial dysfunction on cytosolic nucleotide metabolism  

DEFF Research Database (Denmark)

Several enzymes of the metabolic pathways responsible for metabolism of cytosolic ribonucleotides and deoxyribonucleotides are located in mitochondria. Studies described in this paper suggest dysfunction of the mitochondria to affect these metabolic pathways and limit the available levels of cytosolic ribonucleotides and deoxyribonucleotides, which in turn can result in aberrant RNA and DNA synthesis. Mitochondrial dysfunction has been linked to genomic instability, and it is possible that the limiting effect of mitochondrial dysfunction on the levels of nucleotides and resulting aberrant RNA and DNA synthesis in part can be responsible for this link. This paper summarizes the parts of the metabolic pathways responsible for nucleotide metabolism that can be affected by mitochondrial dysfunction.

2010-01-01

259

Ionization and fragmentation of DNA, RNA bases induced by proton impact  

Energy Technology Data Exchange (ETDEWEB)

We present recent results obtained in the Toulouse's group that deal with proton to base and nucleoside interactions. We stress the weakness of the sugar part in the nucleoside, i.e. the uridine molecule under scrutiny. Since some parts of the fragmentation spectrum correspond to the fragmentation of a 'pure' uracil molecule, i.e. the RNA base, an 'additivity rule' seems to prevail for the nucleoside, something that still has to be confirmed. Moreover, some results that deal with the secondary electronic emission from uracil are also displayed.

2008-02-01

260

An experimental investigation of the Hahn-Noll revenue neutral auction for emissions licenses  

Energy Technology Data Exchange (ETDEWEB)

This paper reports on three series of laboratory experiments designed to test the performance of the Hahn-Noll revenue neutral auction (RNA). An alternative institution, a no-rebate uniform price auction (UPA), is also examined as a benchmark. In these experiments, the RNA markets were little different from UPA markets in terms of either prices or market efficiencies. The two institutions did differ in terms of the distribution of the gains from exchange and of the propensity of bidders to engage in a certain type of overbidding. 25 refs., 13 figs., 3 tabs.

1993-01-01

261

[mRNA level and cytochrome P450 1A activity in the liver of C57BL mice induced by various xenobiotics].  

Science.gov (United States)

The rate of hepatic cytochrome P450 Cypla1 and Cyp1a2 induction was investigated in C57BL male mice during induction with o-aminoazotoluene (OAT), benzo[a]pyrene (BP) and 1,4-dihydroxyanthraquinone (AQ). The Cypla1 mPNA level determined by quantitative RT-competitive PCR increased more than three orders of magnitude during induction with OAT and BP compared with untreated animals and remained unchanged during induction with AQ. The Cypla2 mRNA level was only 8.5, 18.7 and 1.9 times higher during induction with OAT, BP and AQ respectively than in untreated mice. At the same time 7-Ethoxyresorufin-O-deethylase (EROD) and 7-Methoxyresorufin-O-demethylase (MROD) activities of Cypla were also investigated in liver. The increase of Cypla1 mRNA level correlated with the increase of EROD activity. This suggests involvement of the transcriptional mechanism of the inducibility of this enzyme. In the case of Cypla2 there was insignificant increase of its ...

262

Effects of low-intensity prolonged exercise on PGC-1 mRNA expression in rat epitrochlearis muscle.  

Science.gov (United States)

We previously reported that the peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) mRNA in rat epitrochlearis muscle was increased after swimming exercise training. In the present study, we demonstrated further that PGC-1 mRNA expression in the epitrochlearis muscle of 4-5-week-old male Sprague-Dawley rats was increased after a 6-h acute bout of low-intensity swimming exercise. With this increase, the expression level was approximately 8-fold of control and immersion group rats that stayed for 6-h in warm water, maintained at the identical temperature of the swimming barrel (35 degrees C) (p<0.01). Second, PGC-1 mRNA expression in the muscle was found to have increased 6-h after 30 10-s tetani contractions were induced by in vitro electrical stimulation. Finally, PGC-1 mRNA expression in the muscle incubated for 18-h with 0.5mM 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR: ...

2002-08-16

263

Site-specific semisynthetic variant of human hemoglobin  

International Nuclear Information System (INIS)

A single round of Edman degradation was employed to remove the NH_2-terminal valine from isolated #alpha# chains of human hemoglobin. Reconstitution of normal #beta# chains with truncated or substituted #alpha# chains was used to form truncated (des-Val"1-#alpha#1) and substituted ([[1-"1"3C]Gly"1]#alpha#1) tetrameric hemoglobin analogs. Structural homology of the analogs with untreated native hemoglobin was established by using several spectroscopic and physical methods. Functional studies indicate that the reconstituted tetrameric protein containing des-Val"1-#alpha# chains has a higher affinity for oxygen, is less influenced by chloride ions or 2,3-biphosphoglycerate, and shows lower cooperativity than native hemoglobin. These results confirm the key functional role of the #alpha#-chain NH_2 terminus in mediating cooperative oxygen binding across the dimer interface. The NH_2-terminal pK/sub 1/2/ value was determined for the ["1"3C]glycine-substituted analog to be 7.46 +/- 0.09 at ...

264

Onium ions. 34. The methoxydiazonium ion: preparation, /sup 1/H, /sup 13/C, and /sup 15/N NMR and IR structural studies, theoretical calculations, and reaction with aromatics. Attempted preparation and the intermediacy of the hydroxydiazonium ion  

Energy Technology Data Exchange (ETDEWEB)

Nitrous oxide is methylated with CH/sub 3/F ..-->.. SbF/sub 5/F/sub 2/ or with CH/sub 3/O/sup +/SOClF in SO/sub 2/ClF to give the stable methoxydiazonium ion CH/sub 3/ON/sub 2//sup +/ (1), which was characterized by NMR (/sup 15/N, /sup 13/C, /sup 1/H) and FT IR spectroscopic studies. It is stable below -30 /sup 0/C, above which it decomposes, regenerating N/sub 2/O. When reacted with aromatics, such as toluene, 1 gives only methylation products and no methoxy derivatives are formed. Spectroscopic and chemical data indicate that the mesomeric form CH/sub 3/O-N=N/sup +/ is a significant contributor to the overall structure of 1. Consideration of computed charge distribution (4-31 G with full geometry optimization and 4-31 G*) also supports this conclusion. Independent generation of 1 was also studied by solvolysis of methylazoxy triflate and diazotization of methoxylamine with NO/sup +/BF/sub 4//sup -/. Preparation of the elusive ...

1986-04-16

265

Molecular orbitals of nucleons in nucleus-nucleus collisions  

International Nuclear Information System (INIS)

A formalism for the dynamical treatment of the molecular orbitals of valence nucleons in nucleus-nucleus collisions is developed with the use of the coupled-reaction-channel (CRC) method. The Coriolis coupling effects as well as the finite mass effects of the nucleon are taken into account in this model, of rotating molecular orbitals, RMO. First, the validity of the concept is examined from the viewpoint of the multi-step processes in a standard CRC calculation for systems containing two identical [core] nuclei. The calculations show strong CRC effects particularly in the case where the mixing of different l-parity orbitals - called hybridization in atomic physics - occurs. Then, the RMO representation for active nucleons is applied to the same systems and compared to the CRC results. Its validity is investigated with respect to the radial motion (adiabaticity) and the rotation of the molecular axis (radial and rotational coupling). Characteristic molecular orbitals of covalent ...

266

Methionine kinetics and balance at the 1985 FAO/WHO/UNU intake requirement in adult men studied with L-[2H3-methyl-1-13C]methionine as a tracer  

International Nuclear Information System (INIS)

The upper range of the requirement for methionine plus cystine in healthy adults was proposed in 1985 by FAO/WHO/UNU to be 13 mg.kg body wt-1.d-1. To explore the validity of this estimate, five healthy, young adult men were given for 7 d a diet based on an L-amino acid mixture supplying 13 mg methionine.kg-1.d-1 (87 mumol.kg-1.d-1) without cystine. Constant intravenous infusions of L-[2H3-methyl-1-13C]methionine were given on days 5 and 7 while subjects were in the fed and postabsorptive states, respectively. Estimates were made of methionine oxidation, and daily methionine balance was derived from the intake-oxidation data. For the five subjects, methionine balances were -0.9, +0.7, +3.5, -3.1, and -3.8 mg kg-1.d-1, or -6, +5, +23, -21, and -26 mumol.kg-1.d-1. These findings lead to the conclusion that the upper range of the requirement for methionine plus cystine probably exceeds 13 mg.kg-1.d-1 in healthy young adults. The implications of ...

267

Mapping a nucleolar targeting sequence of an RNA binding nucleolar protein, Nop25  

International Nuclear Information System (INIS)

Nop25 is a putative RNA binding nucleolar protein associated with rRNA transcription. The present study was undertaken to determine the mechanism of Nop25 localization in the nucleolus. Deletion experiments of Nop25 amino acid sequence showed Nop25 to contain a nuclear targeting sequence in the N-terminal and a nucleolar targeting sequence in the C-terminal. By expressing derivative peptides from the C-terminal as GFP-fusion proteins in the cells, a lysine and arginine residue-enriched peptide (KRKHPRRAQDSTKKPPSATRTSKTQRRRR) allowed a GFP-fusion protein to be transported and fully retained in the nucleolus. When the peptide was fused with cMyc epitope and expressed in the cells, a cMyc epitope was then detected in the nucleolus. Nop25 did not localize in the nucleolus by deletion of the peptide from Nop25. Furthermore, deletion of a subdomain (KRKHPRRAQ) in the peptide or amino acid substitution of lysine and arginine residues in the subdomain ...

2006-06-10

268

cDNA Cloning and mRNA analysis of PGC-1 in epitrochlearis muscle in swimming-exercised rats.  

Science.gov (United States)

Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1), a cold-inducible coactivator of nuclear receptors, stimulates mitochondrial biogenesis and respiration in muscle cells. In the present study, we first cloned a rat PGC-1 gene from a brown adipose tissue cDNA library which encodes a predicted 796-amino-acid protein and exhibits respectively 98% and 95% identity with the mouse and human homologues. Next, we examined the effect of swimming exercise training on the level of expression of the PGC-1 gene in rat epitrochlearis (Epi) muscle. PGC-1 mRNA level in Epi muscle in rats that swam 2 h a day for 3 and 7 days increased dramatically by 154% and 163%, respectively, compared to the non-exercised control group. PGC-1 mRNA up-regulation was not observed in an immersion group treated at 35 degrees C during the training program but without swimming exercise. These results demonstrate that expression of the PGC-1 gene in Epi muscle ...

2000-08-01

269

Probiotics inhibit enteropathogenic E. coli adherence in vitro by inducing intestinal mucin gene expression.  

Science.gov (United States)

Probiotic agents, live microorganisms with beneficial effects for the host, may offer an alternative to conventional antimicrobials in the treatment and prevention of enteric infections. The probiotic agents Lactobacillus plantarum 299v and Lactobacillus rhamnosus GG quantitatively inhibited the adherence of an attaching and effacing pathogenic Escherichia coli to HT-29 intestinal epithelial cells but did not inhibit adherence to nonintestinal HEp-2 cells. HT-29 cells were grown under conditions that induced high levels of either MUC2 or MUC3 mRNA, but HEp-2 cells expressed only minimal levels of MUC2 and no MUC3 mRNA. Media enriched for MUC2 and MUC3 mucin were added exogenously to binding assays and were shown to be capable of inhibiting enteropathogen adherence to HEp-2 cells. Incubation of L. plantarum 299v with HT-29 cells increased MUC2 and MUC3 mRNA expression levels. From these in vitro studies, we propose the ...

1999-04-01

270

Modulation of gene expression in differentiating 3T3 - L1 preadipocytes  

Energy Technology Data Exchange (ETDEWEB)

3T3 - L1 cells can be induced to differentiate by exposing cell culture to a medium containing 3-isobutyl-1-methyl-xanthine together with insulin and dexamethasone. They have observed that oxalomalate (OMA) which inhibits aconitase thus blocking the citric cycle, also favours differentiation to adipocytes leading to fatty acids accumulation and increased synthesis of specific proteins. They compared the effects of 3-isobutyl-1-methyl-xanthine-insulin-dexamethasone and OMA on the steady-state levels of mRNA of c / EBP, H-ferritin and aconitase / IRE-BP. OMA does not affect the steady-state mRNA amount of C / EBP, H-ferritin and aconitase / IRE-BP but the 3-isobutyl-1-methyl-xanthine-insulin-dexamethasone mixture is able to induce a five-fold increase of mRNA levels for aconitase / IRE-BP. This is the first finding correlating iron metabolism to adipocyte differentiation. Further studies will clarify a possible role for the ...

1997-12-31

271

INDUCIBLE RNAi-MEDIATED GENE SILENCING USING NANOSTRUCTURED GENE DELIVERY ARRAYS  

Energy Technology Data Exchange (ETDEWEB)

RNA interference has become a powerful biological tool over the last decade. In this study, a tetracycline-inducible shRNA vector system was designed for silencing CFP expression and delivered alongside the yfp marker gene into Chinese hamster ovary cells using impalefection on spatially indexed vertically aligned carbon nanofiber arrays (VACNFs). The VACNF architecture provided simultaneous delivery of multiple genes, subsequent adherence and proliferation of interfaced cells, and repeated monitoring of single cells over time. Following impalefection and tetracycline induction, 53.1% 10.4% of impalefected cells were fully silenced by the inducible CFP-silencing shRNA vector. Additionally, efficient CFP-silencing was observed in single cells among a population of cells that remained CFP-expressing. This effective transient expression system enables rapid analysis of gene silencing effects using RNAi in single cells and cell ...

2008-01-01

272

Human cytoplasmic actin proteins are encoded by a multigene family  

Energy Technology Data Exchange (ETDEWEB)

The authors characterized nine human actin genes that they isolated from a library of cloned human DNA. Measurements of the thermal stability of hybrids formed between each cloned actin gene and ..cap alpha..-, ..beta..-, and ..gamma..-actin mRNA demonstrated that only one of the clones is most homologous to sarcomeric actin mRNA, whereas the remaining eight clones are most homologous to cytoplasmic actin mRNA. By the following criteria they show that these nine clones represent nine different actin gene loci rather than different alleles or different parts of a single gene: (i) the restriction enzyme maps of the coding regions are dissimilar; (ii) each clone contains sufficient coding region to encode all or most of an entire actin gene; and (iii) each clone contains sequences homologous to both the 5' and 3' ends of the coding region of a cloned chicken ..beta..-actin cDNA. They conclude, therefore, that ...

1982-06-01

273

Water-soluble cis-[(NHC)PdBr2(TPPTS)] catalysts and their applications in Suzuki-Miyaura coupling of aryl chlorides  

British Library Electronic Table of Contents (United Kingdom)

New palladium(II) complexes (2), bearing NHC/TPPTS ligands, (NHC=benzimidazol-2-ylidene; TPPTS=triphenylphosphine-3,3',3''-trisulfonic acid trisodium salt) have been prepared and characterized by elemental analyses and spectroscopic methods. Their ability to catalyze the Suzuki-Miyaura reaction in neat water has been studied at 100^oC. Very high activities have been observed in the coupling of phenylboronic acid with aryl chlorides in the presence of 1% of the catalyst. We have compared the electronic properties of cis-[PdBr2(NHC)(TPPTS)] with the related complexes, [PdX2(NHC)]2 and [trans-PdBr2(NHC)(pdca)] (pdca=pyridine-2,6-dicarboxyic acid) (3) via three different techniques: cyclic voltammetry, thermogravimetric analysis and ^1^3C NMR spectroscopy.

2011-01-01

274

Two dimensional NMR and NMR relaxation studies of coal structure. Progress report, July 1, 1992--September 30, 1992  

Energy Technology Data Exchange (ETDEWEB)

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with {sup 13}C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed at delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.

1992-11-25

275

Synthesis, characterization and evaluation of antibacterial activity of some thiazolo[3,2-b][1,2,4]triazole incorporating diphenylsulfone moieties  

British Library Electronic Table of Contents (United Kingdom)

A series of thiazolo[3,2-b][1,2,4]triazole incorporating diphenylsulfone moieties were synthesized starting from 5-[4-(4-X-phenylsulfonyl)phenyl]-4H-1,2,4-triazole-3-thioles 3a-c, X=H, Cl, Br. Thus, alkylation of 1,2,4-triazoles 3 with phenacyl bromide or 4-bromophenacyl bromide afforded S-substituted 1,2,4-triazoles 4, 5. These new intermediates 4 and 5, in the presence of H2SO4 (c), were cyclized to 2-[4-(4-X-phenylsulfonyl)phenyl]-6-(4-Y-phenyl)[1,3]thiazolo[3,2-b]-[1, 2,4]-triazoles 6, 7 (I) and not to isomeric thiazolo[2,3-c][1,2,4]-triazoles 6, 7 (II). The newly synthesized compounds were characterized by IR, 1H, 13C NMR and elemental analysis. MS spectra confirmed the formation of thiazolo[3,2-b][1,2,4]triazole 6, 7 (forms I) in detriment of [2,3-c] isomeric compounds (forms II). Th...

2009-01-01

276

Synthesis, characterization and biological evaluation of mononuclear Co(II), Ni(II), Cu(II) and Pd(II) complexes with new N2O2 Schiff base ligands.  

Science.gov (United States)

New tetradentate N(2)O(2) donor Schiff bases and their mononuclear Co(II), Ni(II), Cu(II), and Pd(II) complexes were synthesized and characterized extensively by IR, (1)H-, (13)C-NMR, mass, ESR, conductivity measurements, elemental and thermal analysis. Specifically the magnetic and electronic spectral measurements demonstrate the octahedral structures of cobalt(II), nickel(II) complexes and square planar geometries of copper(II), palladium(II) complexes. All the ligands and complexes were screened for their in vitro antibacterial activity against two gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and two gram-negative bacteria (Escherichia coli, Klebsiella pneumonia). In this study, Pd(II) complexes exhibited potent antibacterial activity against B. subtilis, S. aureus whereas other metal complexes also exerted good activity towards all tested strains even than standard drugs streptomycin and ampicillin. PMID:21297294

2011-02-01

277

Synthesis of novel anode Li4Ti5O12/C with PAN as carbon source and its electrochemical performance  

British Library Electronic Table of Contents (United Kingdom)

A newly carbon-doped Lithium titanate (Li4Ti5O12/C) spinel-type composite material was routinely prepared by a simple solid-state reaction method using carbonization of polyacrylonitrile (PAN) as carbon source in an inert atmosphere. Impedance measurement shows that the resistance of the composite electrode is substantially lower than that of the pure one. Electrochemical performances of the prepared materials were investigated. Results indicate that the composite materials obtained with 10wt.% PAN shows relatively higher specific capacity, better cycling and higher rate performance. The first discharge specific capacity of 158mAhg^-^1, 138mAhg^-^1, and 121mAhg^-^1 were obtained at 0.2C rate, 1/3C rate, and 3C rate at room temperature, respectively. And it was also found that tap density o...

2011-01-01

278

Synthesis of Poly (D L-lactide-co-dl-3,6 dimethyl-morpholine, 2,5 - dione)  

International Nuclear Information System (INIS)

Polypeptides, copolymers of #alpha#-amino acids and #alpha#-hydroxy acids, could prove to be a valuable new class of synthetic biodegradable polymers. In this paper. steps in synthesis of poly (dl-lactide-co-3, 6-dimethylmorpholine-2,5-dione) from dl-lactide and dl-3,6-dimethylmorpholine-2,5-dione was explained. dl-Lactide was synthesized from lactic acid. In the reaction of 2-bromopropionyl chloride and dl-alanine, N-(2-bromopropionyl)-dl-alanine was prepared and this material was converted to its salt and finally this salt was converted to 3,6-dimethylmorpholine-2,5-dione in a sublime r. These two monomers, that is d l-lactide and dl-3,6-dimethylmorpholine-2,5-dione was polymerized by ring-opening polymerization. F T-IR, "1H NMR, "1"3C NMR Spectra were used for structure elucidation of all intermediate compounds and final product.

2001-09-01

279

Synthesis and characterization of diastereomeric (substituted iminodiacetato)(1,2-diaminocyclohexane)platinum(II) complexes  

Energy Technology Data Exchange (ETDEWEB)

Novel complexes of the type (Pt(DACH)(N-R-iminodiacetate)), wherein DACH represents (R,S)- and (R,R)-1,2 diaminocyclohexane and R represents /minus/Me, /minus/EtOH, and /minus/CH/sub 2/Ph groups, have been prepared, purified, and characterized by spectroscopic techniques (/sup 1/H, /sup 13/C, and /sup 195/Pt NMR;MS(FAB);IR) and by the measurement of selected physical properties (pH, pK/sub a/, conductivity, and molecular weights). The data are consistent with the formation of two diastereomeric complexes in unequal proportions in which the N-R-iminodiacetate ligand appears to be bonded as a pseudofacial tridentate chelate. One are of the ligand forms a stable five-membered-ring O,N-chelate while the other arm appears to be involved in ion-pair formation (zwitterion-like) involving the carboxylate anion and the formally positive Pt(II) central metal atom. It has been demonstrated indirectly that an active impurity was present in predictably ...

1988-11-16

280

Syntheses, characterizations and structures of NO donor Schiff base ligands and nickel(II) and copper(II) complexes  

British Library Electronic Table of Contents (United Kingdom)

New Schiff base derivatives (L1 and L2) were prepared by the condensation of 2-hydroxy-3-methoxybenzaldehyde (o-vanillin) and 3-hydroxy-4-methoxybenzaldehyde (iso-vanillin) with 5-methylfurfurylamine. Two new complexes [Ni(L1)2] and [Cu(L1)2] have been synthesized with bidentate NO donor Schiff base ligand (L1). The Ni(II) and Cu(II) atoms in each complex are four coordinated in a square planar geometry. Schiff bases (L1 and L2) and complexes [Ni(L1)2] and [Cu(L1)2] were characterized by elemental analyses, FT-IR, UV-vis, mass and 1H, 13C NMR spectroscopies. The crystal structures of the ligand (L2) and complexes [Ni(L1)2] and [Cu(L1)2] have also been determined by using X-ray crystallographic technique.

2011-01-01

281

Studies of initial stage in coal liquefaction. Effect of decomposition of oxygen-functional groups on coal liquefaction; Ekika hanno no shoki katei ni kansuru kenkyu. 3. Gansanso kannoki no bunkai kyodo to ekika hanno eno eikyo  

Energy Technology Data Exchange (ETDEWEB)

Pretreatment of brown coal in oil was conducted using 1-methyl naphthalene or mixture of tetralin and 1-methyl naphthalene as solvent at temperatures ranging from 300 to 430{degree}C under nitrogen atmosphere. Effects of the solvent properties on the structural change of oxygen-functional groups (OFG) and coal liquefaction were investigated by means of quantitative analysis of OFG and solid state {sup 13}C-NMR measurement. When hydrogen transfer from solvent was insufficient, it was suggested that brown coal molecules loose their hydrogen to be aromatized. While, at lower temperatures ranging from 300 to 350{degree}C, hydrogen contained in brown coal molecules was consumed for the stabilization of pyrolytic radicals, and the deterioration of liquefaction was not observed. When hydrogen transfer from solvent was insufficient at higher temperatures above 400{degree}C in nitrogen atmosphere during pretreatment in oil, crosslinking like benzofuran ...

1996-10-28

282

Structure determination and investigation on cytotoxicity of potassium dichlorido(l-prolinato)platinate(II) versus chlorido(dimethyl sulfoxide)(l-prolinato)platinum(II) complex -In vitro antitumor deactivation by Cl^-/dmso ligand exchange  

British Library Electronic Table of Contents (United Kingdom)

Potassium dichlorido(l-prolinato)platinate(II), K[PtCl"2(l-pro"?"H)] (1), and chlorido(dimethyl sulfoxide)(l-prolinato)platinum(II), [PtCl(l-pro"?"H)(dmso)] (2), were synthesized by ligand substitution reactions. Both complexes were characterized by ^1H, ^1^3C, and ^1^9^5Pt NMR spectroscopy, elemental analysis, and HR-ESI-MS. The molecular structures of 1 and 2 were determined by single crystal X-ray diffraction, proving bidentate coordinated l-prolinato ligand and SP-4-4 configuration of 2a. With the help of DFT calculations stability of possible isomers of 1 and 2 was studied. A considerable difference in the in vitro cytotoxicity of 1 versus 2a (exchange of one chlorido ligand by dmso) against four human cancer cell lines was found.

2011-01-01

283

Stereospecific ligands and their complexes. Part VII. Synthesis, characterization and in vitro antitumoral activity of platinum(II) complexes with O,Oprime-dialkyl esters of (S,S)-ethylenediamine-N,Nprime-di-2-(4-methyl)pentanoic acid  

British Library Electronic Table of Contents (United Kingdom)

Platinum(II) complexes (1-4) with bidentate N,Nprime-ligands, O,Oprime-dialkyl esters (alkyl = ethyl, n-propyl, n-butyl and n-pentyl), of (S,S)-ethylenediamine-N,Nprime-di-2-(4-methyl)pentanoic acid were synthesized and characterized by IR, 1H NMR and 13C NMR spectroscopy and elemental analysis. DFT calculations were performed for the complexes and it was found that only one diastereoisomer could be formed. Cytotoxic activity of complexes 1-4 was determined against chronic lymphocytic leukemia cells (CLL) and compared to the activity of ligand precursors L12HCl-L42HCl and corresponding palladium(II) complexes, [PdCl2L] (L = L1-L4). The complexes were found to exhibit significantly higher antitumor activities than cisplatin on CLL cells. Cytotoxic effect of platinum(II) complexes on CLL cel...

2011-01-01

284

Stable isotopes of authigenic minerals in variably-saturated fractured tuff  

Energy Technology Data Exchange (ETDEWEB)

Identifying stable isotope variation and mineralogical changes in fractured rock may help establish the history of climatic and geomorphological processes that might affect the isolation properties of a waste repository site. This study examines the use of the stable isotope ratios of oxygen ({sup 18}O/{sup 16}O) and carbon ({sup 13}C/{sup 12}C) in authigenic minerals as hydrogeochemical tools tracing low-temperature rock-water interaction in variably-saturated fractured stuff. Isotopic compositions of fracture-filling and rock matrix minerals in the Apache Leap tuff, near Superior, Arizona were concordant with geothermal temperatures and in equilibrium with water isotopically similar to present-day meteoric water and groundwater. Oxygen and carbon isotope ratios of fracture-filling, in unsaturated fractured tuff, displayed an isotopic gradient believed to result from near-surface isotopic enrichment due to evaporation rather than the effects ...

1988-11-01

285

Series fan-powered boxes: Their impact on indoor air quality and comfort  

Energy Technology Data Exchange (ETDEWEB)

Until the concerns about indoor air quality (IAQ) reached a peak in the last five years, interior zones of office buildings were traditionally served with cooling-only shut-off variable air volume (VAV) boxes. Heat gains from lighting and equipment, in addition to those from occupants themselves, caused supply air quantities of 13 C to 15 C (55 F to 60 F) air to be sustained at rates on the order of 2.5 L/s per square meter (0.5 cfm per square feet), a rate that most designers at the time felt would provide a comfortable and well ventilated environment. More recently, the reduction in lighting loads, the use of cold air systems, and, most importantly, the concern that acceptable indoor air quality may not be maintained at low air flow rates, has led to a different solution in interior zones: the series fan-powered mixing box.

1996-07-01

286

Phospholipid asymmetry in large unilamellar vesicles induced by transmembrane pH gradients  

Energy Technology Data Exchange (ETDEWEB)

The influence of membrane pH gradients on the transbilayer distribution of some common phospholipids has been investigated. The authors demonstrate that the transbilayer equilibrium of the acidic phospholipids egg phosphatidylglycerol (EPG) and egg phosphatidic acid (EPA) can be manipulated by membrane proton gradients, whereas phosphatidylethanolamine, a zwitterionic phospholipid, remains equally distributed between the inner and outer monolayers of large unilamellar vesicles (LUVs). Asymmetry of EPG is examined in detail and demonstrated by employing three independent techniques: ion-exchange chromatography, {sup 13}C NMR, and periodic acid oxidation of the (exterior) EPG headgroup. In the absence of a transmembrane pH gradient ({Delta}pH) EPG is equally distributed between the outer and inner monolayers of LuVs. When vesicles composed of either egg phosphatidylcholine (EPC) or DOPC together with 5 mol % EPG are prepared with a transmembrane ...

1989-05-16

287

Nuclear magnetic resonance spectroscopy in the structure elucidation and biosynthesis of natural products  

Energy Technology Data Exchange (ETDEWEB)

Examination of a chloroform extract of Dracaena loureiri Gagnep (Agavaceae), a Thia medicinal plant possessing antibacterial activity, has led to the isolation of fifteen flavenoids. The biogenic relationships among these flavenoids isolated were briefly discussed. Definition of the skeleton and the unambiguous assignment of all of the protons of the isolates was achieved through extensive 2D-homonuclear chemical shift correlation, nuclear Overhauser effect (NOE) difference spectroscopy and 2D-NOE experiments. The {sup 1}H and {sup 13}C NMR spectra of staurosporine, a potent biologically active agent from Streptomyces staurosporeus, were unambiguously assigned by using 2D homonuclear chemical shift correlation, NOE, {sup 1}H-detected heteronuclear multiple-quantum coherence via direct coupling and via multiple-bond coupling for resonance assignments of protonated and nonprotonated carbons, respectively. S. Staurosporeus was found to utilize ...

1988-01-01

288

Novel platinum(II) complexes of long chain aliphatic diamine ligands with oxalato as the leaving group: Comparative cytotoxic activity relative to chloride precursors  

Energy Technology Data Exchange (ETDEWEB)

Platinum complexes play an important role in the development of anticancer drugs. Their cytotoxicity can be influenced by the nature of the leaving ligands, due to the hydrolysis reaction that occurs prior to the binding of the platinum complex to DNA. Also, non-leaving groups such as lipophilic diamines may affect cellular uptake. In this work, we describe the synthesis of platinum(II) complexes having oxalato and long chain aliphatic N-alkyl ethylenediamines as ligands. The products were characterized by elemental analyses, infrared spectroscopy and {sup 1}H, {sup 13}C and {sup 195}Pt NMR spectroscopy. Biological activity was assessed against tumor cell lines (A{sub 549}, B16-F1, B16-F10, MDA-MB-231) and non-tumor cell lines (BHK-21 and CHO). The length of the carbon chain affects the cytotoxicity and the oxalato complexes were less cytotoxic than the respective chloride-containing analogues. (author)

2010-07-01

289

Novel non-discoid chiral copper(II)-salen type [N2O2] donor Schiff base complexes with a cyclohexane diamine spacer: synthesis, electrochemistry, columnar mesomorphism and DFT study  

British Library Electronic Table of Contents (United Kingdom)

A series of new non-discoid chiral copper(ii)-salen type complexes, [Cu((4-CnH2n+1O)2salen)], n = 14, 16, 18 and salen = N,N'-cyclohexane bis (salicylideneiminato), containing 4-substituted alkoxy tails in the side aromatic rings and a cyclohexane spacer, have been prepared and their mesogenic properties investigated. The compounds were characterised by Fourier transform infra-red spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy, UV-vis spectroscopy and fast atom bombardment mass spectrometry. Mesomorphic properties of these compounds were studied by polarising optical microscopy, differential scanning calorimetry and X-ray diffraction (XRD). The ligands are non-mesogenic but the complexes exhibited enantiotropic rectangular columnar mesophases (Colr) with extended temperat...

2011-01-01

290

Methimazole complexes of platinum(II): Synthesis, characterization and redox behavior  

British Library Electronic Table of Contents (United Kingdom)

A variety of platinum(II) complexes of methimazole (2-mercapto-1-methylimidazole; HImS=neutral form and ImS=thiolate form), coordinated in both thione and thiolate forms, have been isolated by reacting methimazole with [PtCl(terpy)]Cl (terpy=2,2prime:6prime,2Prime terpyridine), [PtCl2(bipy)] (bipy=bipyridine), [PtCl2(o-phen)] (o-phen=o-phenanthroline), [PtCl2(CH3CN)2] and [PtCl2(COD)] (COD=1,5-cyclooctadiene). These complexes were characterized by electronic absorption, IR and NMR (1H, 13C, 195Pt) spectroscopies. Molecular structure of [Pt(bipy)(HImS)2]Cl23H2O (3a3H2O) has been established by single crystal X-ray crystallography. Platinum thiolate complex, [Pt(ImS)2(HImS)2] (5), could be obtained by treatment of [Pt(HImS)4]Cl2 with sodium methoxide in methanol. The solution of 5 in organic...

2011-01-01

291

Metal coordination and selectivity with oxine ligands bound to silica polyamine composites  

British Library Electronic Table of Contents (United Kingdom)

A series of oxine ligands, 5-X, 8 OH C9H6N (X = H, Cl, SO3H) have been covalently bound to a silica gel polyamine composite made from a silanized amorphous silica xerogel and poly(allylamine) (BP-1) by the Mannich reaction. The resulting modified composites WP-4(X = H), CB-1(X = Cl), and SB-1(X = SO3H) were characterized by elemental analysis, FTIR, and solid state CPMAS-13C-NMR. Using the analytical data before and after the ligand modification, the ligand loading could be estimated and in combination with metal ion capacities a metal to ligand ratio could be obtained. The composites WP-4 and CB-1 both showed ratios of approximately 1 : 1 while the sulfonate modified composite, SB-1, showed a metal to ligand ratio of 1 : 2. This is tentatively interpreted in terms of a zwitterionic oxine ...

2010-01-01

292

Light liquid hydrocarbons from the catalytic pyrolysis of sewage sludge lipid  

Energy Technology Data Exchange (ETDEWEB)

The lipid obtained by the toluene extraction of a dried raw Atlanta sewage sludge by the Soxhlet method, was pyrolyzed over activated alumina at atmospheric pressure. A range of weight hourly space velocities (WHSV) from 0.22-1.60/h and a range of temperatures from 400-480[degree]C were selected. A 70 wt % yield of light liquid hydrocarbons was obtained at a WHSV of 0.46/h and 450[degree]C. The sulfur and nitrogen contents of the pyrolysis products were much lower than products from direct liquefaction of sludge. Infrared spectra and [sup 13]C nuclear magnetic resonance confirmed the absence of carbonyl groups in the products. Gas chromatography showed a uniform hydrocarbon chain length distribution across the C[sub 7] to C[sub 17] mass range. The gas product consisted mainly of carbon dioxide and hydrocarbons. Lauric acid was used as a model to study the decarboxylation. The effects of catalyst loading and catalyst moisture content were ...

1993-01-01

293

Interaction of cis-diamminediaquoplatinum(II) with adenosylcobalamin and alkylcobalamins  

Energy Technology Data Exchange (ETDEWEB)

The interaction of cis-diamminediaquoplatinum(II) nitrate with adenosylcobalamin and a series of alkylcobalamins was studied by carbon-13 nuclear magnetic resonance spectroscopy and by electronic spectroscopy. With these cobalamins cis-(Pt(NH/sub 3/)/sub 2/(OH/sub 2/)/sub 2/)/sup 2 +/ forms adducts in which N(3) of the 5,6-methylbenzimidazole moiety is co-ordinated to platinum(II) rather than to cobalt(III) of the corrin. The chemical shifts of the 5'-methylene carbon of adenosylcobalamin-platinum adduct and of the Co-methyl carbon of the methylcobalamin-platinum adduct are characteristic of these cobalamins in the base-off form. Furthermore, these cobalamin-platinum complexes have visible spectra identical to those of the cobalamins in acidic solution. The /sup 13/C NMR spectrum of the adenosylcobalamin-platinum complex suggests the presence of a second adduct in which platinum(II) complexes are co-ordinated to both the N(3) of the ...

1980-01-01

294

Interaction of 8 MeV /sup 12/C with /sup 88/Sr; neutron transfer, inelastic scattering and spin alignment of the 2/sup +/ state of /sup 12/C  

Energy Technology Data Exchange (ETDEWEB)

Using a Q3D magnetic spectrometer the elastic and inelastic scattering of /sup 12/C on /sup 88/Sr and the neutron pick-up (/sup 12/C, /sup 13/C) has been studied. The spin alignment of the inelastically excited 2/sup +/ state of /sup 12/C (4.43 MeV) has been deduced from the line shapes broadened by the ..gamma..-decay in flight. Thus for each m-substate a full angular distribution was obtained. The m = 1 substate shows a shifted interference minimum, which is explained by the different strength of the Coulomb and nuclear amplitudes in the m-substates. The analysis of the data on elastic scattering, inelastic scattering, alignment and the neutron transfer can be described consistently with one choice of the optical model parameters.

1982-04-01

295

Human tissue factor pathway inhibitor (TFPI) gene: Complete genomic structure and localization on the genetic map of chromosome 2q  

Energy Technology Data Exchange (ETDEWEB)

Tissue factor pathway inhibitor (TFPI), a protease inhibitor that circulates in association with plasma lipoproteins (VLDL, LDL and HDL), helps to regulate the extrinsic blood coagulation cascade. The authors have cloned a 125-kb genomic region containing the entire human TFPI gene on six overlapping cosmids and prepared a restriction map of this contig to clarify gene structure. More than half (45 kb) of the 85-kb gene is occupied with 5[prime] noncoding elements: coding begins at exon 3. A HindIII RFLP identified with one cosmid was genotyped in the CEPH panel of 559 reference families. Linkage analysis using markers on human chromosome 2 located the TFPI gene on 2q, 36 cM proximal to D2S43(pYNZ15) and 13 cM distal to the crystalline [gamma]-polypeptide locus CRYGP1(p5G1). 31 refs., 3 figs., 3 tabs.

1993-08-01

296

Geochemical study on origin of natural gases in Japanese oil and gas fields  

Energy Technology Data Exchange (ETDEWEB)

The origin of natural gas in the Japanese oil and gas fields are geochemically studied. Samples are taken from structural natural gas, surface gas seepage, water-dissolved natural gas and coal-field gas of the Japan Sea coast area. The origins of primary hydrocarbons are classified into bacteria gas and thermogenic gas, the latter being subclassified into gas in oil production zone with the per million deviation of the carbon isotope (/sup 13/C/sup 1/) of methane less than -35 and those gases with maturity higher than this. Surface gas seepage is subjected to migration and bacterial oxidation. Coal gas is similar to oil gas. The CO/sub 2/ concentration is 0 - 2% and /sup 13/CO/sub 2/ deviations from -30 - +30. The origin can be barely estimated from the isotopic composition because of the wide secondary change in the composition. The origin and migration of gas from the gas field of northern Niigata are not similar to those in the southern ...

1988-05-01

297

Enzymatic synthesis and carbon-13 nuclear magnetic resonance conformational studies of disaccharides containing #beta#-D-galactopyranosyl and #beta#-D-[1-"1"3C]Galactopyranosyl residues  

International Nuclear Information System (INIS)

Partially purified UDPgalactosyltransferase (EC 2.4.1.22) from bovine milk has been used to synthesize millimolar amounts of compounds such as Gal#beta#(1#->#4)Glc, Gal#beta#(1#->#4)GlcNAc-#beta#-hexanolamine, and Gal#beta#(1#->#4)-GlcNAc#beta#(1#->#4)GlcNAc. The same method has been used to prepare similar compounds containing "1"3C-enriched galactopyranosyl moieties. Gal#beta#(1#->#4)GlcNAc-#beta#-hexanolamine was also synthesized in a solid-phase system in which the GlcNAc-#beta#-hexanolamine glycoside was covalently linked to agarose beads. At pH 7.0 and at 1 to 5 mM Mn"2"+"+ the yields of the galactosyl saccharides are greater than 90% by using 10% excess of UDPGal donor. The use of a 90% enriched [1-"1"3C]galactosyl residue allowed the determination of the most abundant conformer about the galactopyranosyl-glycoside linkage by analysis of the carbon-carbon coupling constants from Cl to Gal to the C3', C4', and C5' of GlcNAc or Glc. 3 figures, 1 table.

298

Constituents of fruit pulp of Maytenus salicifolia and complete 1D/2D NMR data of 3?-hydroxy-D:B-friedo-olean-5-ene  

British Library Electronic Table of Contents (United Kingdom)

A mixture of long-chain hydrocarbons constituted by nonacosane (29C, 7.5%), hentriacontane (31C, 48.3%), and tritriacontane (33C, 30.1%), the ester 1?-acetyloxymethylpentacosa-20?-enyl 10-hydroxydecanoate (2), ?-amyrin (3), friedelin (4), and lupeol (5), and 3?-hydroxy-D:B-friedo-olean-5-ene (6) were identified as constituents of fruits of Maytenus salicifolia Reissek (Celastraceae). The structural formula and the stereochemistry of compound 6 were established by the data obtained through 1H and 13C NMR spectroscopy, including DEPT-135 and 2D (HMQC, HMBC, and NOESY) experiments. By analysis of the spectral data, it was possible to correct seven chemical shift assignments of compound 6, which were erroneous attributed and published in the scientific literature.

2010-01-01

299

Anomalous carbon isotope fractionation between atmospheric CO/sub 2/ and dissolved inorganic carbon induced by intense photosynthesis  

Energy Technology Data Exchange (ETDEWEB)

A stable isotope mass-balance of dissolved inorganic carbon during a blue-green algae bloom in a softwater lake demonstrates that at low partial pressure of carbon dioxide there must be a large net negative carbon isotope fractionation between atmospheric CO/sub 2/ and the CO/sub 2/ absorbed by lake water at pH = 9.5. Chemical enhancement of CO/sub 2/ invasion at high pH by the reaction CO/sub 2/ + OH/sup -/ ..-->.. HCO/sub 3//sup -/ at large apparent film thicknesses may result in carbon isotope fractionation approaching that for a hydroxide solution. This phenomenon, coupled with a decrease in the photosynthetic fractionation, forced the surface water of a softwater lake to achieve increasingly negative delta /sup 13/C values during an algal bloom, which is in the opposite sense to the trend that results from photosynthesis under less extreme conditions. This and other similar systems must operate under non-equilibrium (kinetic) ...

1987-04-01

300

Actinides produced by /sup 12/C + /sup 242/Pu and /sup 16/O + /sup 238/U reactions  

Energy Technology Data Exchange (ETDEWEB)

The cross sections for /sup 250/Fm, /sup 244-246/Cf, /sup 242-244/Cm, and /sup 242/Am/sup g-italic/ produced by the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions leading to the same compound nucleus of /sup 254/Fm have been measured by using radiochemical methods. The excitation functions show that the difference between the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions can be attributed mainly to the Coulomb barriers. Our results were compared with others reported previously for /sup 22/Ne+ /sup 232/Th, /sup 12/C+ /sup 238/U, /sup 12/C+ /sup 240,241/Pu, /sup 13/C+ /sup 241/Pu, /sup 16/O+ /sup 233/U, and /sup 16/O+ /sup 242/Pu reaction systems, and support a mechanism involving transfer of ..cap alpha..-particle clusters (C,Be,He) from projectile to target for the production of Cf and Cm isotopes.

1986-09-01

301

Actinides produced by /sup 12/C + /sup 242/Pu and /sup 16/O + /sup 238/U reactions  

International Nuclear Information System (INIS)

The cross sections for /sup 250/Fm, /sup 244-246/Cf, /sup 242-244/Cm, and /sup 242/Am/sup g/ produced by the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions leading to the same compound nucleus of /sup 254/Fm have been measured by using radiochemical methods. The excitation functions show that the difference between the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions can be attributed mainly to the Coulomb barriers. Our results were compared with others reported previously for /sup 22/Ne+ /sup 232/Th, /sup 12/C+ /sup 238/U, /sup 12/C+ /sup 240,241/Pu, /sup 13/C+ /sup 241/Pu, /sup 16/O+ /sup 233/U, and /sup 16/O+ /sup 242/Pu reaction systems, and support a mechanism involving transfer of #alpha#-particle clusters (C,Be,He) from projectile to target for the production of Cf and Cm isotopes.

302

Absorption of the atmospheric CO{sub 2} by oceanic biota near the air-sea interface  

Energy Technology Data Exchange (ETDEWEB)

The oceanic phytoplancton productivity may essentially influence the total rate of the atmospheric CO{sub 2} absorption by the ocean - that is, a considerable amount of CO{sub 2} will be taken-up in the 50 micrometers thick layer near the air-sea interface. Even if phytoplancton production constitutes only 5% of the total oceanic biota production, this will increase the rate of CO{sub 2} absorption more than twice compared with the present estimates. The reason is that metabolic activity of phytoplancton leads to the emergence in a thin scin (50 micrometers, the average size of phytoplancton cells) layer near the water surface of an additional minimum in the CO{sub 2} partial pressure profile and of an additional maximum of {Delta} {sup 13}C in the same area. These two extremums cannot be detected if the corresponding characteristics are averaged over any microscopic area in the well mixing layer that is more than 1 meter deep, which is usually ...

1997-12-31

303

The ribosome and the mechanism of protein synthesis  

Energy Technology Data Exchange (ETDEWEB)

In virtually all forms of life on earth, proteins in each cell are made according to a genetic blueprint, in the form of DNA. The translation of copies of this genetic blueprint (in the form of messenger RNA) into polypeptides is performed on the ribosome, a highly complex molecular machine composed of RNAs and proteins. To this end, special adaptor molecules called transfer RNAs are lined up by the ribosome in the sequence dictated by the genetic code, such that the amino acids carried by these molecules can be linked into a polypeptide. Several cofactors are involved in these processes, some of which require energy freed up by GTP hydrolysis. Although the ribosome was discovered more than 50 years ago, its structure has only been solved recently by X-ray crystallography. Another technique, cryo-electron microscopy, is starting to contribute toward our understanding of the ribosome's function, by portraying its conformational changes and binding ...

2006-05-01

304

The Morphology, Ontogeny, and Small Subunit rRNA Gene Sequence Analysis of Diophrys parappendiculata n. sp. (Protozoa, Ciliophora, Euplotida), a New Marine Ciliate from Coastal Waters of Southern China  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT. The morphology, morphogenesis, and phylogeny of Diophrys parappendiculata n. sp., a large marine ciliate isolated from the coastal waters of Daya Bay, southern China, were investigated. This new species is characterized by a combination of its large size, appendiculata-pattern of ciliature, and bipartite adoral zone of membranelles. The main stages of morphogenesis during binary fission were also recorded and described. Comparisons of morphological characteristics with similar congeners support the validity of the new species. The small subunit rRNA gene sequence of D. parappendiculata is 96.3-99.94% similar to those of four other congeners; it differs in four nucleotides from that of Diophrys appendiculata (i.e. structural similarity was 99.94%). Phylogenetic analysis indicates ...

2011-01-01

305

Profiling gene expression responses of coral larvae (Acropora millepora) to elevated temperature and settlement inducers using a novel RNA-Seq procedure  

British Library Electronic Table of Contents (United Kingdom)

Abstract Elevated temperatures resulting from climate change pose a clear threat to reef-building corals; however, the traits that might influence corals- survival and dispersal during climate change remain poorly understood. Global gene expression profiling is a powerful hypothesis-forming tool that can help elucidate these traits. Here, we applied a novel RNA-Seq protocol to study molecular responses to heat and settlement inducers in aposymbiotic larvae of the reef-building coral Acropora millepora. This analysis of a single full-sibling family revealed contrasting responses between short- (4-h) and long-term (5-day) exposures to elevated temperatures. Heat shock proteins were up-regulated only in the short-term treatment, while the long-term treatment induced the down-regulation of rib...

2011-01-01

306

Oxidation of Elemental Sulfur by Fusarium solani Strain THIF01 Harboring Endobacterium Bradyrhizobium sp.  

British Library Electronic Table of Contents (United Kingdom)

Nineteen fungal strains having an ability to oxidize elemental sulfur in mineral salts medium were isolated from deteriorated sandstones of Angkor monuments. These fungi formed clearing zone on agar medium supplemented with powder sulfur due to the dissolution of sulfur. Representative of the isolates, strain THIF01, was identified as Fusarium solani on the basis of morphological characteristics and phylogenetic analyses. PCR amplification targeting 16S rRNA gene and analyses of full 16S rRNA gene sequence indicated strain THIF01 harbors an endobacterium Bradyrhizobium sp.; however, involvement of the bacterium in the sulfur oxidation is still unclear. Strain THIF01 oxidized elemental sulfur to thiosulfate and then sulfate. Germination of the spores of strain THIF01 was observed in a liqui...

2010-01-01

307

One-step RNA pathogen detection with reverse transcriptase activity of a mutated thermostable Thermus aquaticus DNA polymerase  

British Library Electronic Table of Contents (United Kingdom)

We describe the cloning and characterization of a mutated thermostable DNA polymerase from Thermus aquaticus (Taq) that exhibits an increased reverse transcriptase activity and is therefore designated for one-step PCR pathogen detection using established real-time detection methods. We demonstrate that this Taq polymerase mutant (Taq M1) has similar PCR sensitivity and nuclease activity as the respective Taq wild-type DNA polymerase. In addition, and in marked contrast to the wild-type, Taq M1 exhibits a significantly increased reverse transcriptase activity especially at high temperatures (>60degreeC). RNA generally hosts highly stable secondary structure motifs, such as hairpins and G-quadruplexes, which complicate, or in the worst case obviate, reverse transcription (RT). Thus, RT at hi...

2010-01-01

308

Modeling protein synthesis from a physicist's perspective: a toy model  

CERN Document Server

Proteins are polymers of amino acids. These macromolecules are synthesized by intracellular machines called {\\it ribosome}. Although, traditionally, the experimental investigation of protein synthesis has been an active area of research in molecular cell biology, important quantitative models of this phenomenon have been reported mostly in the research journals devoted to statistical physics and related interdisciplinary topics. From the perspective of a physicist, protein synthesis is a phenomenon of {\\it classical transport of interacting ribosomes on a messenger RNA (mRNA) template} that dictates the sequence of the amino acids on the protein. Here we bring this frontier area of contemporary research into the classroom by appropriate simplification of the models and methods. In particular, we develope a simple toy model and analyze it by some elementary techniques of non-equilibrium statistical mechanics to predict the average rate of ...

2007-01-01

309

Distinctive Responses of Metabolically Active Microbiota to Acidification in a Thermophilic Anaerobic Digester  

British Library Electronic Table of Contents (United Kingdom)

Acidification is one of the most common and serious problems inducing process failure in anaerobic digesters. The production of volatile fatty acids (VFAs) mainly triggers acidic shock. However, little is known about the bacteria involved in the processes of acidogenic metabolism, such as fermentation and reductive acetogenesis. Here, the metabolic responses of a methanogenic community to the acidification and resulting process deterioration were investigated using transcriptional profiling of both the 16S rRNA and formyltetrahydrofolate synthetase (FTHFS) genes. The 16S rRNA-based analyses demonstrated that the dynamic shift of bacterial populations was closely correlated with reactor performance, especially with VFA accumulation levels. The pH drop accompanied by an increase in VFAs stim...

2011-01-01

310

Transcription of the E2F-1 gene is rendered cell cycle dependent by E2F DNA-binding sites within its promoter.  

UK PubMed Central (United Kingdom)

The cell cycle-regulatory transcription factor E2F-1 is regulated by interactions with proteins such as the retinoblastoma gene product and by cell cycle-dependent alterations in E2F-1 mRNA abundance....Full Text Available

1994-10-01

311

The YTH Domain Is a Novel RNA Binding Domain*  

UK PubMed Central (United Kingdom)

The YTH (YT521-B homology) domain was identified by sequence comparison and is found in 174 different proteins expressed in eukaryotes. It is characterized by 14 invariant residues within an α-helix/β-sheet...Full Text Available

2010-05-07

312

The CYP2A3 gene product catalyzes coumarin 7-hydroxylation in human liver microsomes  

Energy Technology Data Exchange (ETDEWEB)

Three cDNAs, designated IIA3, IIA3v, and IIA4, coding for P450s in the CYP2A gene subfamily were isolated from a {lambda}gt11 library prepared from human hepatic mRNA. Only three nucleotide differences and a single amino acid difference, Leu{sup 160}{yields}His, were found between IIA3 and IIA3v, indicating that they are probably allelic variants. IIA4 displayed 94% amino acid similarity with IIA3 and IIA3v. The three cDNAs were inserted into vaccinia virus, and recombinant viruses were used to infect human hepatoma Hep G2 cells. Only IIA3 was able to produce an enzyme that had a reduced CO-bound spectrum with a {lambda}{sub max} at 450 nm. This expressed enzyme was able to carry out coumarin 7-hydroxylation and ethoxycoumarin O-deethylation. cDNA-expressed IIA3v and IIA4 failed to incorporate heme and were enzymatically inactive. Analysis of IIA proteins in human liver microsomes, using antibody against rat IIA2, revealed two proteins of 49 and 50 kDa, the former ...

1990-02-06

313

The CYP2A3 gene product catalyzes coumarin 7-hydroxylation in human liver microsomes  

International Nuclear Information System (INIS)

Three cDNAs, designated IIA3, IIA3v, and IIA4, coding for P450s in the CYP2A gene subfamily were isolated from a #lambda#gt11 library prepared from human hepatic mRNA. Only three nucleotide differences and a single amino acid difference, Leu"1"6"0#->#His, were found between IIA3 and IIA3v, indicating that they are probably allelic variants. IIA4 displayed 94% amino acid similarity with IIA3 and IIA3v. The three cDNAs were inserted into vaccinia virus, and recombinant viruses were used to infect human hepatoma Hep G2 cells. Only IIA3 was able to produce an enzyme that had a reduced CO-bound spectrum with a #lambda#_m_a_x at 450 nm. This expressed enzyme was able to carry out coumarin 7-hydroxylation and ethoxycoumarin O-deethylation. cDNA-expressed IIA3v and IIA4 failed to incorporate heme and were enzymatically inactive. Analysis of IIA proteins in human liver microsomes, using antibody against rat IIA2, revealed two proteins of 49 and 50 kDa, the former of ...

1990-02-01

314

TGFB1-Induced Extracellular Expression of TGFBIp and Inhibition of TGFBIp Expression by RNA Interference in a Human Corneal Epithelial Cell Line  

UK PubMed Central (United Kingdom)

Purpose.To report the increased production of extracellular transforming growth factor β-induced protein (TGFBIp) by human corneal epithelial cells (HCECs) after induction...Full Text Available

2011-02-01

315

Specific in vitro initiation of transcription on the adenovirus type 2 early and late EII transcription units.  

UK PubMed Central (United Kingdom)

Three transcription units are present in the adenovirus type 2 region EII. Transcription units EIIaE and EIIaL encode the mRNA for the 72,000-dalton DNA binding protein, early and late in the lytic...Full Text Available

1981-12-01

316

Silencing of SARS-CoV spike gene by small interfering RNA in HEK 293T cells  

International Nuclear Information System (INIS)

Two candidate small interfering RNAs (siRNAs) corresponding to severe acute respiratory syndrome-associated coronavirus (SARS-CoV) spike gene were designed and in vitro transcribed to explore the possibility of silencing SARS-CoV S gene. The plasmid pEGFP-optS, which contains the codon-optimized SARS-CoV S gene and expresses spike-EGFP fusion protein (S-EGFP) as silencing target and expressing reporter, was transfected with siRNAs into HEK 293T cells. At various time points of posttransfection, the levels of S-EGFP expression and amounts of spike mRNA transcript were detected by fluorescence microscopy, flow cytometry, Western blot, and real-time quantitative PCR, respectively. The results showed that the cells transfected with pEGFP-optS expressed S-EGFP fusion protein at a higher level compared with those transfected with pEGFP-S, which contains wildtype SARS-CoV spike gene sequence. The green fluorescence, mean fluorescence intensity, and SARS-CoV S ...

2004-11-26

317

Scyl1 Facilitates Nuclear tRNA Export in Mammalian Cells by Acting at the Nuclear Pore Complex  

UK PubMed Central (United Kingdom)

Scyl1 is an evolutionarily conserved N-terminal protein kinase-like domain protein that plays a role in COP1-mediated retrograde protein trafficking in mammalian cells. Furthermore, loss of Scyl1 function...Full Text Available

2010-07-15

318

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

Energy Technology Data Exchange (ETDEWEB)

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

319

Polyadenylated H3 histone transcripts and H3 histone variants in alfalfa.  

UK PubMed Central (United Kingdom)

Histone H3 mRNAs were found in polyA(+) fractions of total RNA prepared from alfalfa plants, calli and somatic embryos. The sequence analysis of cDNAs revealed the presence of a polyA tail on independent...Full Text Available

1989-04-25

320

One-step RNA pathogen detection with reverse transcriptase activity of a mutated thermostable Thermus aquaticus DNA polymerase.  

Science.gov (United States)

We describe the cloning and characterization of a mutated thermostable DNA polymerase from Thermus aquaticus (Taq) that exhibits an increased reverse transcriptase activity and is therefore designated for one-step PCR pathogen detection using established real-time detection methods. We demonstrate that this Taq polymerase mutant (Taq M1) has similar PCR sensitivity and nuclease activity as the respective Taq wild-type DNA polymerase. In addition, and in marked contrast to the wild-type, Taq M1 exhibits a significantly increased reverse transcriptase activity especially at high temperatures (>60 degrees C). RNA generally hosts highly stable secondary structure motifs, such as hairpins and G-quadruplexes, which complicate, or in the worst case obviate, reverse transcription (RT). Thus, RT at high temperatures is desired to weaken or melt secondary structure motifs. To demonstrate the ability of Taq M1 for RNA detection of pathogens, we ...

2010-02-01

321

Molecular cloning of chicken metallothionein. Deduction of the complete amino acid sequence and analysis of expression using cloned cDNA  

Energy Technology Data Exchange (ETDEWEB)

A cDNA library was constructed using RNA isolated from the livers of chickens which had been treated with zinc. This library was screened with a RNA probe complementary to mouse metallothionein-I (MT), and eight chicken MT cDNA clones were obtained. All of the cDNA clones contained nucleotide sequences homologous to regions of the longest (375 bp) cDNA clone. The latter contained an open reading frame of 189 bp, and the deduced amino acid sequence indicates a protein of 63 amino acids of which 20 are cysteine residues. Amino acid composition and partial amino acid sequence analyses of purified chicken MT protein agreed with the amino acid composition and sequence deduced from the cloned cDNA. Amino acid sequence comparison establish that chicken MT shares extensive homology with mammalian MTs. Southern blot analysis of chicken DNA indicates that the chicken MT gene is not a part of a large family of related sequences, but rather is likely to be ...

1988-01-25

322

MicroRNA Let-7f Inhibits Tumor Invasion and Metastasis by Targeting MYH9 in Human Gastric Cancer  

UK PubMed Central (United Kingdom)

BackgroundMicroRNAs (miRNAs) are important regulators that play key roles in tumorigenesis and tumor progression. A previous report has shown that let-7 family members can act as...Full Text Available

323

MMP-9 Gene Ablation and TIMP-4 Mitigate PAR-1-Mediated Cardiomyocyte Dysfunction: A Plausible Role of Dicer and miRNA  

UK PubMed Central (United Kingdom)

Although matrix metalloproteinase-9 (MMP-9) is involved in cardiomyocytes contractility dysfunction, tissue inhibitor of metalloproteinase-4 (TIMP-4) mitigates the effect of MMP-9, and proteinase-activated...Full Text Available

2010-07-01

324

Large T1 oligonucleotides of Moloney leukemia virus missing in an env gene recombinant, HIX, are present on an intracellular 21S Moloney viral RNA species.  

UK PubMed Central (United Kingdom)

HIX, a recombinant derived from Moloney leukemia virus, has an envelope glycoprotein different from that of the Moloney virus. HIX and Moloney viruses share the majority of the large T1 oligonucleotides...Full Text Available

1978-06-01

325

Isolation and characterization of cDNA clones for human skeletal muscle alpha actin.  

UK PubMed Central (United Kingdom)

Two cDNA libraries corresponding to polyA+ RNA from human adult skeletal muscle have been constructed by cloning in the PstI site of pBR322. Skeletal alpha actin cDNA clones have been isolated and characterized....Full Text Available

1983-06-11

326

Intragenic rearrangements of a mycoreovirus induced by the multifunctional protein p29 encoded by the prototypic hypovirus CHV1-EP713  

UK PubMed Central (United Kingdom)

Mycoreovirus 1 (MyRV1), a member of the Reoviridae family possessing a genome consisting of 11 dsRNA segments (S1–S11), and the prototype hypovirus (CHV1-EP713)...Full Text Available

2008-12-01

327

Insulin regulation of protein biosynthesis in differentiated 3T3 adipocytes. Regulation of glyceraldehyde-3-phosphate dehydrogenase  

Energy Technology Data Exchange (ETDEWEB)

The effect of insulin on protein biosynthesis was examined in differentiated 3T3-L1 and 3T3-F442A adipocytes. Insulin altered the relative rate of synthesis of specific proteins independent of its ability to hasten conversion of the fibroblast (preadipocyte) phenotype to the adipocyte phenotype. Although more than one pattern of response to insulin was observed, the authors focused on the induction of a Mr 33,000 protein which was identified as the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Exposure of 3T3 adipocytes to insulin throughout differentiation specifically increased GAPDH activity and protein content by 2- to 3-fold as compared to 3T3 adipocytes differentiated in the absence of insulin. These changes in enzyme activity and content could be accounted for by a 4-fold increase in the relative rate of synthesis of GAPDH and a 9-fold increase in hybridizable mRNA levels. Within 2 h of insulin addition to 3T3 adipocytes differentiated ...

1985-10-05

328

Identification of a nucleoside triphosphate binding site on calf thymus RNA polymerase II  

Energy Technology Data Exchange (ETDEWEB)

A nucleoside triphosphate binding site on calf thymus RNA polymerase II was identified by using photoaffinity analogues of adenosine 5'-triphosphate and guanosine 5'-triphosphate. Both radiolabeled 8-azidoadenosine 5'-triphosphate (8-N3ATP) and radiolabeled 8-azidoguanosine 5'-triphosphate (8-N3GTP) bound to a single polypeptide of this enzyme. This polypeptide has a molecular mass of 37 kilodaltons and an isoelectric point of 5.4. Ultraviolet (UV) irradiation was necessary for photolabeling to occur. In addition, no labeling occurred when the probe was prephotolyzed or when the enzyme was inactivated. Furthermore, photolabeling of the enzyme could be decreased by preincubation with natural substrates. To provide evidence that the radiolabeled polypeptide forms a part of the domain of the nucleoside triphosphate binding site, experiments were performed using unlabeled 8-N3ATP. Although this unlabeled analogue was not a substrate ...

1986-01-14

329

Hypoxia down-regulates sFlt-1 (sVEGFR-1) expression in human microvascular endothelial cells by a mechanism involving mRNA alternative processing  

UK PubMed Central (United Kingdom)

sFlt-1 (soluble Flt-1) potently inhibits angiogenesis by binding extracellularly to VEGF (vascular endothelial growth factor). In the present paper, we report that hypoxia down-regulates sFlt-1 expression...Full Text Available

2011-06-01

330

Highly Ordered Spatial Organization of the Structural Long Noncoding NEAT1 RNAs within Paraspeckle Nuclear Bodies  

UK PubMed Central (United Kingdom)

Paraspeckles (PSPs) are nuclear bodies associated with the retention in the nucleus of specific mRNAs. Two isoforms of a long noncoding RNA (NEAT1_v1/Menε and NEAT1_v2/Menβ)...Full Text Available

2010-11-15

331

Extraribosomal functions associated with the C terminus of the 37/67?kDa laminin receptor are required for maintaining cell viability  

UK PubMed Central (United Kingdom)

The 37/67 kDa laminin receptor (LAMR) is a multifunctional protein, acting as an extracellular receptor, localizing to the nucleus, and playing roles in rRNA processing and ribosome assembly....Full Text Available

2010-05-01

332

Expression of alternatively spliced human T-lymphotropic virus type I pX mRNA in infected cell lines and in primary uncultured cells from patients with adult T-cell leukemia/lymphoma and healthy carriers.  

UK PubMed Central (United Kingdom)

Although human T-cell lymphotropic virus type I (HTLV-I) is the etiologic agent of adult T-cell leukemia/lymphoma (ATL), the role of viral gene expression in the progression to and maintenance of the...Full Text Available

1992-04-01

333

Dissecting toxin immunity in virus-infected killer yeast uncovers an intrinsic strategy of self-protection  

UK PubMed Central (United Kingdom)

Toxin-secreting “killer” yeasts were initially identified >40 years ago in Saccharomyces cerevisiae strains infected with a double-stranded RNA “killer”...Full Text Available

2006-03-07

334

Discrimination of Listeria monocytogenes from other Listeria species by ligase chain reaction.  

UK PubMed Central (United Kingdom)

A ligase chain reaction assay based on a single-base-pair difference in the V9 region of the 16S rRNA gene (16S rDNA) was developed to distinguish between Listeria monocytogenes and other Listeria species....Full Text Available

1992-11-01

335

Differentiation associated regulation of microRNA expression in vivo in human CD8+ T cell subsets  

UK PubMed Central (United Kingdom)

BackgroundThe differentiation of CD8+ T lymphocytes following priming of naïve cells is central in the establishment of the adaptive immune response. Yet, the...Full Text Available

336

Differential expression of human Fas mRNA species upon peripheral blood mononuclear cell activation.  

UK PubMed Central (United Kingdom)

Human Fas/Apo-1 is a cell-surface protein that mediates apoptosis upon ligation with Fas ligand. The gene lies on the long arm of chromosome 10, consists of nine exons, and spans more than 26 kb of...Full Text Available

1995-09-15

337

Detection of Atopobium vaginae in postmenopausal women by cultivation-independent methods warrants further investigation.  

Science.gov (United States)

We sequenced 16S rRNA genes from the vaginal swab contents of a postmenopausal woman with asymptomatic bacterial vaginosis (BV). Sequences from Atopobium vaginae were the most commonly detected. In a survey of 35 other postmenopausal women, this organism was detected in 44% with BV but not in any subjects deemed healthy. PMID:15071062

2004-04-01

338

Cumulus expansion, nuclear maturation and connexin 43, cyclooxygenase-2 and FSH receptor mRNA expression in equine cumulus-oocyte complexes cultured in vitro in the presence of FSH and precursors for hyaluronic acid synthesis  

UK PubMed Central (United Kingdom)

The aim of this study was to investigate cumulus expansion, nuclear maturation and expression of connexin 43, cyclooxygenase-2 and FSH receptor transcripts in equine cumuli oophori during in vivo and...Full Text Available

339

Cordycepin Blocks Lung Injury-Associated Inflammation and Promotes BRCA1-Deficient Breast Cancer Cell Killing by Effectively Inhibiting PARP  

UK PubMed Central (United Kingdom)

Cordycepin has been shown to interfere with a myriad of molecular processes from RNA elongation to kinase activity, and prevents numerous inflammatory processes in animal models. Here we show in a mouse...Full Text Available

2011-09-01

340

Comparison of the NucliSens easyMAG and Qiagen BioRobot 9604 Nucleic Acid Extraction Systems for Detection of RNA and DNA Respiratory Viruses in Nasopharyngeal Aspirate Samples?  

UK PubMed Central (United Kingdom)

The NucliSens easyMAG and BioRot 9604 automated nucleic acid extraction systems were evaluated and compared with the manual QIAamp (Qiagen) extraction method for their abilities to extract nucleic acid...Full Text Available

2008-07-01

341

Cloning, chromosomal assignment, and regulation of the rat thyrotropin receptor: Expression of the gene is regulated by thyrotropin, agents that increase cAMP levels, and thyroid autoantibodies  

International Nuclear Information System (INIS)

A rat thyrotropin (thyroid-stimulating hormone, TSH) receptor cDNA was isolated that encoded a protein of 764 amino acids, M_r 86,528. Transfection of the cDNA caused COS-7 cells to develop a TSH-sensitive adenylate cyclase response and the ability to bind "1"2"5I-labeled TSH; both activities were similar to those of rat FRTL-5 thyroid cells and not duplicated by lutropin. The gene represented by the cDNA was assigned to mouse chromosome 12 and human chromosome 14. Northern analyses identified two species of mRNA, 5.6 and 3.3 kilobases, in FRTL-5 thyroid cells; the transcripts appeared to differ only in the extent of their 3' noncoding sequences. There were minimal amounts of the two mRNAs in rat ovary, and neither was detected in RNA preparations from rat testis, liver, lung, brain, spleen, and FRT thyroid cells, which do not have a functional TSH receptor. TSH decreased both mRNA species 3- to 4-fold within 8 hr in FRTL-5 ...

1990-01-01

342

Cadmium down-regulation of kidney Sp1 binding to mouse SGLT1 and SGLT2 gene promoters: Possible reaction of cadmium with the zinc finger domain of Sp1  

UK PubMed Central (United Kingdom)

Cadmium (Cd) exposure causes glucosuria (glucose in the urine). Previously, it was shown that Cd exposure of primary cultures of mouse kidney cells (PMKC) decreased mRNA levels of the glucose...Full Text Available

2010-05-01

343

Arc/Arg3.1 mRNA Global Expression Patterns Elicited by Memory Recall in Cerebral Cortex Differ for Remote Versus Recent Spatial Memories  

UK PubMed Central (United Kingdom)

The neocortex plays a critical role in the gradual formation and storage of remote declarative memories. Because the circuitry mechanisms of systems-level consolidation are not well understood, the...Full Text Available

344

Application of a Newly Developed ARB Software-Integrated Tool for In Silico Terminal Restriction Fragment Length Polymorphism Analysis Reveals the Dominance of a Novel pmoA Cluster in a Forest Soil  

UK PubMed Central (United Kingdom)

TRF-CUT, an ARB-implemented tool, was developed to predict in silico the terminal restriction fragments of aligned small-subunit rRNA gene or functional gene sequences. Application of this new tool...Full Text Available

2005-03-01

345

An ultraviolet-inducible adenosine-adenosine cross-link reflects the catalytic structure of the Tetrahymena ribozyme  

Energy Technology Data Exchange (ETDEWEB)

When a shortened enzymatic version of the Tetrahymena self-splicing intervening sequence (IVS) RNA is placed under catalytic conditions and irradiated at 254 nm, a covalent cross-link forms with high efficiency. The position of the cross-link was mapped by using three independent methods: RNase H digestion, primer extension with reverse transcriptase, and partial hydrolysis of end-labeled RNA. The cross-link is chemically unusual in that it joins two adenosines, A57 and A95. Formation of this cross-link depends upon the identity and concentration of divalent cations present and upon heat-cool renaturation of the IVS in a manner that parallels conditions required for optimal catalytic activity. Furthermore, cross-linking requires the presence of sequences within the core structure, which is conserved among group I intervening sequences and necessary for catalytic activity. Together these correlations suggest that a common folded structure ...

1990-06-12

346

Alternative mRNA Splicing Produces a Novel Biologically Active Short Isoform of PGC-1?*  

UK PubMed Central (United Kingdom)

The transcriptional co-activator PGC-1α regulates functional plasticity in adipose tissue by linking sympathetic input to the transcriptional program of adaptive thermogenesis. We report here...Full Text Available

2009-11-20

347

A Targeted Bypass Screen Identifies Ynl187p, Prp42p, Snu71p, and Cbp80p for Stable U1 snRNP/Pre-mRNA Interaction?  

UK PubMed Central (United Kingdom)

To understand how DEXD/H-box proteins recognize and interact with their cellular substrates, we have been studying Prp28p, a DEXD/H-box splicing factor required for switching the U1 snRNP with the U6...Full Text Available

2009-07-01

348

Epitope mapping and functional analysis of sigma A and sigma NS proteins of avian reovirus  

International Nuclear Information System (INIS)

We have previously shown that avian reovirus (ARV) #sigma#A and #sigma#NS proteins possess dsRNA and ssRNA binding activity and suggested that there are two epitopes on #sigma#A (I and II) and three epitopes (A, B, and C) on #sigma#NS. To further define the location of epitopes on #sigma#A and #sigma#NS proteins and to further elucidate the biological functions of these epitopes by using monoclonal antibodies (MAbs) 62, 1F9, H1E1, and 4A123 against the ARV S1133 strain, the full-length and deletion fragments of S2 and S4 genes of ARV generated by polymerase chain reaction (PCR) were cloned into pET32 expression vectors and the fusion proteins were overexpressed in Escherichia coli BL21 strain. Epitope mapping using MAbs and E. coli-expressed deletion fragments of #sigma#A and #sigma#NS of the ARV S1133 strain, synthetic peptides, and the cross reactivity of MAbs to heterologous ARV strains demonstrated that epitope II on #sigma#A was located at ...

2005-02-20

349

cDNA cloning, sequence analysis and organ distribution of horse preproendothelin-2.  

Science.gov (United States)

We cloned and characterized horse preproendothelin-2 (PPET-2) cDNA from intestinal tissue. The cDNA encoded 178 amino acids of the PPET-2 polypeptide, in which a 21-amino-acid mature endothelin-2 peptide and a 16-amino acid endothelin-2-like peptide were found. For the open reading frame the correspondence of horse PPET-2 cDNA with those of the ferret, human, dog, mouse and rat was 85.1%, 84.9%, 82.1%, 77.8% and 77.2%, respectively. Analysis of the organ distribution of PPET-2 mRNA by reverse transcription-polymerase chain reaction demonstrated that the kidney, stomach and small intestine are major sites of expression of the PPET-2 gene. Surprisingly, the mRNA is not detected in the large intestine, where high expression is demonstrated in the mouse and rat. This difference may result from the underlying functional differences of the large intestine between a herbivore (horse) and an omnivore (mouse and rat). PMID:15838341

2004-11-01

350

The mitochondrial genome of the entomophagous endoparasite Xenosvesparum (Insecta: Strepsiptera)  

Energy Technology Data Exchange (ETDEWEB)

In this study, the nearly complete sequence (14,519 bp) of the mitochondrial DNA (mtDNA) of the entomophagous endoparasite Xenos vesparum (Insecta: Strepsiptera) is described. All protein coding genes (PCGs) are in the arrangement known to be ancestral for insects, but three tRNA genes (trnA, trnS(gcu), and trnL(uag)) have transposed to derived positions and there are three tandem copies of trnH, each of which is potentially functional. All of these rearrangements except for that of trnL(uag) is within the short span between nad3 and nad4 and there are numerous blocks of unassignable sequence in this region, perhaps as remnants of larger scale predisposing rearrangements. X. vesparum mtDNA nucleotide composition is strongly biased toward As and Ts, as is typical for insect mtDNAs. There is also significant strand skew in the distribution of these nucleotides, with the J-strand being richer in A than T and in C than G, and the N-strand showing an opposite skew for ...

2005-12-01

351

Systems Biology Approach in Chlamydomonas Reveals Connections between Copper Nutrition and Multiple Metabolic Steps[C][W][OA  

Science.gov (United States)

In this work, we query the Chlamydomonas reinhardtii copper regulon at a whole-genome level. Our RNA-Seq data simulation and analysis pipeline validated a 2-fold cutoff and 10 RPKM (reads per kilobase of mappable length per million mapped reads) (~1 mRNA per cell) to reveal 63 CRR1 targets plus another 86 copper-responsive genes. Proteomic and immunoblot analyses captured 25% of the corresponding proteins, whose abundance was also dependent on copper nutrition, validating transcriptional regulation as a major control mechanism for copper signaling in Chlamydomonas. The impact of copper deficiency on the expression of several O2-dependent enzymes included steps in lipid modification pathways. Quantitative lipid profiles indicated increased polyunsaturation of fatty acids on thylakoid membrane digalactosyldiglycerides, indicating a global impact of copper deficiency on the photosynthetic apparatus. Discovery of a putative plastid copper chaperone ...

2011-04-01

352

Purification and analysis of RNA polymerase II transcription factors by using wheat germ agglutinin affinity chromatography.  

Science.gov (United States)

We recently found that many RNA polymerase II transcription factors are modified with N-acetylglucosamine residues. These sugar moieties confer upon transcription factors an ability to bind the lectin wheat germ agglutinin. We have taken advantage of this interaction to devise a purification procedure for the "GC-box" binding transcription factor Sp1. Crude nuclear extracts are first subjected to wheat germ agglutinin affinity chromatography and then subjected to sequence-specific DNA affinity chromatography. The Sp1 protein purified by this procedure is at least 95% pure, and the overall recovery is greater than 80%. In addition to yielding larger quantities of Sp1 than conventional schemes, the new purification procedure is also simpler and more rapid. We show that wheat germ agglutinin affinity chromatography can also be used to purify the glycosylated forms of the CCAAT-binding transcription factor. Thus, wheat germ agglutinin affinity chromatography may aid ...

1989-03-01

353

Nuclear factor of activated T cell (NFAT) transcription proteins regulate genes involved in adipocyte metabolism and lipolysis  

Science.gov (United States)

NFAT involvement in adipocyte physiological processes was examined by treatment with CsA and/or GSK3{beta} inhibitors (Li{sup +} or TZDZ-8), which prevent or increase NFAT nuclear translocation, respectively. CsA treatment reduced basal and TNF{alpha}-induced rates of lipolysis by 50%. Adipocytes preincubated with Li{sup +} or TZDZ-8 prior to CsA and/or TNF{alpha}, exhibited enhanced basal rates of lipolysis and complete inhibition of CsA-mediated decreased rates of lipolysis. CsA treatment dramatically reduced the mRNA levels of adipocyte-specific genes (aP2, HSL, PPAR{gamma}, ACS and Adn), compared with control or TNF{alpha}-treatment, whereas Li{sup +} pretreatment blocked the inhibitory effects of CsA, and mRNA levels of aP2, HSL, PPAR{gamma}, and ACS were found at or above control levels. NFAT nuclear localization, assessed by EMSA, confirmed that CsA or Li{sup +} treatments inhibited or increased NFAT nuclear translocation, respectively. ...

2007-09-21

354

Increased transcription of the c-myc oncogene in two methylcholanthrene-induced quail fibroblastic cell lines  

Energy Technology Data Exchange (ETDEWEB)

The expression of three c-onc genes (c-erb, c-myc, c-myb) was investigated in five cell lines established from fibrosarcomas induced with 20-methylcholanthrene (MCA) of Japanese quails. These cell lines showed low levels of the three c-onc genes, with the exception of two cell lines that accumulated moderate (MCAQ 1-4) and large amounts (MCAQ 3-5) of c-myc RNA. Molecular cloning and restriction endonuclease analyses indicated that expression of c-myc in these two cell lines were not associated with detectable rearrangements in the c-myc locus, that the size of the c-myc transcript (2.7 kb) in MCAQ 3-5 was similar to that of the normal c-myc messenger RNAs (mRNA) and that the transcriptional activatin observed in MCAQ 3-5 was not mediated by the LTR (long terminal repeat) of a proximate ALV (avian leukosis virus) provirus. Finally, when analyzed with the restriction enzymes Msp I and Hpa II, the c-myc locus of MCAQ 3-5 and MCAQ 1-4 was found ...

1984-12-01

355

Human T-cell lymphotropic virus type III infection of the central nervous system: a preliminary in situ analysis  

Energy Technology Data Exchange (ETDEWEB)

Patients with acquired immunodeficiency syndrome (AIDS) are subject to a spectrum of central nervous system (CNS) disorders. Recent evidence implicates the human T-cell lymphotropic virus type III (HTLV-III) in the pathogenesis of some of these illnesses, although the cells infected by the virus have yet to be identified. Using in situ hybridization, the authors examined brain tissue from two patients with AIDS encephalopathy for the presence of HTLV-III RNA. In both cases, viral RNA was detected and concentrated in, though not limited to, the white matter. The CNS cells most frequently infected included macrophages, pleomorphic microglia, and multinucleated giant cells. Less frequently, cells morphologically consistent with astrocytes, oligodendroglia, and rarely neurons were also infected. The findings strengthen the association of HTLV-III with the pathogenesis of AIDS encephalopathy. In situ hybridization can be applied to routinely ...

1986-11-07

356

Hsp22 (HspB8/H11) knockdown induces sam68 expression and stimulates proliferation of glioblastoma cells  

British Library Electronic Table of Contents (United Kingdom)

Abstract Sam68 (Src-associated protein in mitosis 68-kDa) is a multifunctional protein, known to govern cellular signal transduction, transcription, RNA metabolism, proliferation, apoptosis, and HIV-1 replication. Although intrinsic mechanisms that modulate Sam68 function are beginning to emerge, the regulatory events contributing to its expression remain elusive. We previously reported that heat shock protein-22 (Hsp22) antagonizes Sam68 function in rev-response element (RRE)-mediated gene expression. We now demonstrate that Sam68 levels correlate inversely with Hsp22 in a variety of cells, including U87, Jurkat, 293T, and U-937. In U87 glioblastoma cells, which contained high levels of Hsp22 than other cell lines tested, Hsp22 knockdown dramatically increased both Sam68 mRNA and protein,...

2011-01-01

357

Heat shock factor binds to heat shock elements upstream of heat shock protein 70a and Samui genes to confer transcriptional activity in Bombyx mori diapause eggs exposed to 5^oC  

British Library Electronic Table of Contents (United Kingdom)

To understand the molecular mechanisms of how 5^oC-incubation activates mRNA expression of Hsp70a and Samui genes in Bombyx mori diapause eggs, we first searched the 5'-upstream regions of the Hsp70a and Samui genes for heat shock elements (HSEs) and found two regions [Hsp70aHSE-1 (-95 to -58) and -2 (-145 to -121), and SamuiHSE-1 (-84 to -55) and -2 (-304 to -290)] corresponding to HSEs (repeats of nGAAn and/or nTTCn). We cloned four cDNAs encoding heat shock factor (HSF)-a2 (627 amino acids), -b (685 aa), -c (682 aa) and -d (705 aa), which were produced by alternative splicing. When we exposed diapause eggs to 5^oC beginning at 2 day post-oviposition to break diapause, HSFd mRNA only increased after chilling for 6-8 days, a pattern very similar to those of Hsp70a and Samui mRNAs. To exam...

2011-01-01

358

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

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

359

Four small puzzles that Rosetta doesn't solve  

CERN Document Server

A complete macromolecule modeling package must be able to solve the simplest structure prediction problems. Despite recent successes in high resolution structure modeling and design, the Rosetta software suite fares poorly on deceptively small protein and RNA puzzles, some as small as four residues. To illustrate these problems, this manuscript presents extensive Rosetta results for four well-defined test cases: the 20-residue mini-protein Trp cage, an even smaller disulfide-stabilized conotoxin, the reactive loop of a serine protease inhibitor, and a UUCG RNA tetraloop. In contrast to previous Rosetta studies, several lines of evidence indicate that conformational sampling is not the major bottleneck in modeling these small systems. Instead, approximations and omissions in the Rosetta all-atom energy function currently preclude discriminating experimentally observed conformations from de novo models at atomic resolution. These molecular ...

2011-01-01

360

Magnetic silica extraction for low-viremia human immunodeficiency virus type 1 genotyping.  

Science.gov (United States)

Nucleic acid extraction and human immunodeficiency virus type 1 (HIV-1) genotyping using the NucliSens miniMAG platform and the TruGene HIV-1 genotyping kit gave HIV-1 sequence data from HIV-1-negative plasma spiked with 100 copies/ml reference HIV-1 RNA and from low-viremia clinical samples (<500 copies/ml) without the need for ultracentrifugation or nested second-round PCR. PMID:17122019

2006-11-22

361

Influence of chromatin molecular changes on RNA synthesis during embryonic development  

International Nuclear Information System (INIS)

Two aspects of the chromatin repeat length (r_l) are discussed: (i) Why is r_l longer for slowly dividing cells than in rapidly dividing cells?, and (ii) Why is the temporal evolution of r_l a decreasing function of time (t) in mammalian cortical neurons whereas it is an increasing function of t for granule cells around the time of birth? These questions are discussed in terms of a hypothesis which assumes a correlation between deoxyribonucleic acid (DNA) packaging, transcription, and replication. (author). 27 refs.

362

Acute gastric erosions in the rat. II. Viability of the gastric mucosa  

Energy Technology Data Exchange (ETDEWEB)

The autoradiographic appearance of the gastric mucosa, 5 hours after administration of indomethacin, was investigated in 29 adult rats. Indomethacin induced superficial gastric erosions. Autoradiography demonstrated the presence of viable gastric cells (as deduced by their ability to incorporate 3H-cytidin, an RNA precursor) not only in the mucosa without erosions, but also in the mucosa underneath the superficial erosions. The results indicate that indomethacin induced gastric erosions are not the superficial expression of a necrotic process taking place in the full thickness of the gastric mucosa at a particular site. A lumen-borne mechanism appears to be responsible for the formation of erosive areas in the mucosa.

1981-01-01

363

Viral RNA testing and automation on the bead-based CBNE detection microsystem.  

Energy Technology Data Exchange (ETDEWEB)

We developed prototype chemistry for nucleic acid hybridization on our bead-based diagnostics platform and we established an automatable bead handling protocol capable of 50 part-per-billion (ppb) sensitivity. We are working towards a platform capable of parallel, rapid (10 minute), raw sample testing for orthogonal (in this case nucleic acid and immunoassays) identification of biological (and other) threats in a single sensor microsystem. In this LDRD we developed the nucleic acid chemistry required for nucleic acid hybridization. Our goal is to place a non-cell associated RNA virus (Bovine Viral Diarrhea, BVD) on the beads for raw sample testing. This key pre-requisite to showing orthogonality (nucleic acid measurements can be performed in parallel with immunoassay measurements). Orthogonal detection dramatically reduces false positives. We chose BVD because our collaborators (UC-Davis) can supply samples from persistently infected animals; and because ...

2008-09-01

364

Two and 8-azido photoaffinity probes. 2. Studies on the binding process of 2-5A synthetase by photosensitive ATP analogues  

International Nuclear Information System (INIS)

The photoaffinity probes [#gamma#-"3"2P]2-azidoATP (2-N_3ATP) and [#alpha#-"3"2P]8-azido-ATP (8-N_3ATP) were used to investigate the binding of ATP to highly purified 2-5A synthetase. 2-N_3APT and 8-N_3ATP are substrates for 2-5A synthetase. In this study the authors show that 2- and 8-N_3ATP are competitive inhibitors of the enzymatic conversion of ATP to 2-5A. Ultraviolet irradiation results in the photoinsertion of 2-N_3ATP and 8-N_3ATP into the enzyme. The covalent photoinsertion of [#alpha#-"3"2P]8-N_3ATP into the 2-5A synthetase is proportional to the inactivation of the enzyme as UV irradiation is increased. Photolabeling of 2-5A synthetase is saturated at 1.5 mM 2-N_3ATP and 2.0 mM 8-N_3ATP. Computer analysis of the curvilinear Scatchard plots of the 2-5A synthetase suggest the presence of high-affinity and low-affinity binding sites that may correspond to the acceptor and the 2'-adenylation sites of the enzyme. The competition of nucleotides for the covalent photoinsertion of ...

365

Pteromalus puparum venom impairs host cellular immune responses by decreasing expression of its scavenger receptor gene.  

Science.gov (United States)

Insect host/parasitoid interactions are co-evolved systems in which host defenses are balanced by parasitoid mechanisms to disable or hide from host immune effectors. Although there is a rich literature on these systems, parasitoid immune-disabling mechanisms have not been fully elucidated. Here we report on a newly discovered immune-disabling mechanism in the Pieris rapae/Pteromalus puparum host/parasitoid system. Because venom injections and parasitization suppresses host phagocytosis, we turned attention to the P. rapae scavenger receptor (Pr-SR), posing the hypothesis that P. puparum venom suppresses expression of the host Pr-SR gene. To test our hypothesis, we cloned a full-length cDNA of the Pr-SR. Multiple sequences alignment showed the deduced amino acid sequence of Pr-SR is similar to scavenger receptors of other lepidopterans. Bacterial and bead injections induced Pr-SR mRNA and protein expression, which peaked at 4h post-bead injection. Venom injection ...

2011-07-22

366

Protein-coding and non-coding gene expression analysis in differentiating human keratinocytes using a three-dimensional epidermal equivalent.  

Science.gov (United States)

The epidermal compartment is complex and organized into several strata composed of keratinocytes (KCs), including basal, spinous, granular, and cornified layers. The continuous process of self-renewal and barrier formation is dependent on a homeostatic balance achieved amongst KCs involving proliferation, differentiation, and cell death. To determine genes responsible for initiating and maintaining a cornified epidermis, organotypic cultures comprised entirely of stratified KCs creating epidermal equivalents (EE) were raised from a submerged state to an air/liquid (A/L) interface. Compared to the array profile of submerged cultures containing KCs predominantly in a proliferative (relatively undifferentiated) state, EEs raised to an A/L interface displayed a remarkably consistent and distinct profile of mRNAs. Cultures lifted to an A/L interface triggered the induction of gene groups that regulate proliferation, differentiation, and cell death. Next, differentially expressed microRNAs ...

2010-05-25

367

Localisation of the neuropeptide PACAP and its receptors in the rat parathyroid and thyroid glands.  

Science.gov (United States)

PACAP (pituitary adenylate cyclase activating polypeptide) is widely distributed neuropeptide acting via three subtypes of receptors, PAC(1), VPAC(1) and VPAC(2). Here we examined the localisation and nature of PACAP-immunoreactive nerves in the rat thyroid and parathyroid glands and defined the distribution of PAC(1), VPAC(1) and VPAC(2) receptor mRNA's. In the parathyroid gland a large number of nerve fibres displaying PACAP-immunoreactivity were distributed beneath the capsule, around blood vessels and close to glandular cells. Most of the PACAP-nerves were sensory, since they co-stored CGRP (calcitonin-gene-related peptide) and were sensitive to capsaicin-treatment. mRNA's for PAC(1) and VPAC(2) receptors occurred in the parathyroid gland, mainly located in the glandular cells. In the thyroid gland PACAP-immunoreactive nerve fibres were associated with blood vessels, thyroid follicles and parafollicular C-cells. A high degree of ...

2010-12-19

368

Gene rearrangement and radiation carcinogenesis  

International Nuclear Information System (INIS)

The development of leukemia and thyroid cancer is characterized by activation of the abl oncogene and ret oncogene, respectively. In order to clarify the relationship between these gene aberrations and radiation, the pro-myelogenous leukemia-derived cell line HL60 and the thyroid cancer-derived cell line 8505C, were irradiated in vitro with 100Gy of X-rays. RNA was then extracted from 10"8 cells of the respective cell lines and examined by the reverse transcription PCR method for rearrangements of abl and ret genes. Five kinds of positive bands were observed in the HL-60 cells irradiated with 100Gy of X-ray. Similarly, six positive bands were also observed in the 8505C cells irradiated with 100Gy. In vitro X-irradiation activation of oncogenes found in radiation induced cancers imply that gene rearrangement by X-rays is involved in the development of malignant tumors. Furthermore, in an experiment to detect radiation effects in A-bomb survivors, ...

1993-11-01

369

{alpha}- and {beta}-Cyclodextrin [2]rotaxanes with (diethylenetriamine)platinum(II) stoppers  

Energy Technology Data Exchange (ETDEWEB)

A series of dinuclear platinum(II) complexes, [(dien)Pt(NH{sub 2}(CH{sub 2}){sub n}NH{sub 2})Pt(dien)]Cl{sub 4} (dien = diethylenetriamine, n = 8, 9, 10, and 12) and their corresponding [2]rotaxanes with {alpha}-cyclodextrin ({alpha}-CD), [(dien)Pt{l_brace}NH{sub 2}(CH{sub 2}){sub n}NH{sub 2}{center_dot}{alpha}-CD{r_brace}Pt(dien)]Cl{sub 4}, have been synthesized and characterized by {sup 1}H, {sup 13}C, and {sup 195}Pt NMR spectroscopy and electrospray mass spectrometry. The rotaxanes were prepared by reacting the {l_brace}NH{sub 2}(CH{sub 2}){sub n}NH{sub 2}{center_dot}{alpha}-CD{r_brace} pseudorotaxanes with [Pt(dien)]Cl, to stopper the included linear {alpha},{omega}-diaminoalkane chains with the inert Pt(II) end groups. The kinetics of the self-assembly and dissociation of the {beta}-CD rotaxane, [(dien)Pt{l_brace}NH{sub 2}(CH{sub 2}){sub 10}NH{sub 2}{center_dot}{beta}-CD{r_brace}Pt(dien)]{sup 4+}, were investigated by using {sup 1}H NMR ...

2005-12-15

370

Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification  

Science.gov (United States)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake ...

2006-09-13

371

Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification  

Energy Technology Data Exchange (ETDEWEB)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake ...

2006-09-13

372

Square planar platinum(II) complexes: Synthesis, IR spectroscopy, and hydration equilibrium of Pt[sup II]L(CN)[sub 2] (L = 4,4[prime]-(t-Bu)[sub 2]-2,2[prime]-bpy)  

Energy Technology Data Exchange (ETDEWEB)

The hydration behavior of a number of square planar Pt(II) bis(cyano) complexes has been examined, and the limiting stoichiometries are related to the steric requirements of the dinitrogen bidentate ligands coordinated to the metal center. In particular, the IR, UV/vis, and [sup 1]H, [sup 13]C, and [sup 195]Pt NMR spectroscopic data for the compound Pt[sup II]dtbipy(CN)[sub 2] [dtbipy = 4,4[prime]-[l brace]C(CH[sub 3])[sub 3][r brace][sub 2]-2,2[prime]-bpy] have been determined and show that, at relative humidities (rh) above [approximately]40%, this complex sorbs five water molecules at room temperature. The sorption process consists of a rapid step in which one H[sub 2]O adds to the complex and which appears to be independent of rh, followed by a slower, rh-dependent step leading to the final stoichiometry. In contrast, the analogous 2,2[prime]-bpy complex sorbs no water under these conditions, while the 4,4[prime]-(CH[sub 3])[sub ...

1992-12-23

373

Radiation testing of organic ion exchange resins  

International Nuclear Information System (INIS)

A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of "1"3"7Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by Boulder Scientific Co. (Mead, Colorado). One of the key parameters in the assessment of the organic based ion exchange materials is its useful lifetime in the radioactive and chemical environment that will be encountered during waste processing. The focus of the work presented in this report is the radiation stability of the CS-100 and the RF resins. The scope of the testing included one test with a sample of the CS-100 resin and testing of two batches of the RF resin (BSC-187 and BSC-210). Samples of the exchangers were irradiated with a "6"0Co source to a total absorbed dose ...

1983-04-11

374

Radiation testing of organic ion exchange resins  

Energy Technology Data Exchange (ETDEWEB)

A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of {sup 137}Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by Boulder Scientific Co. (Mead, Colorado). One of the key parameters in the assessment of the organic based ion exchange materials is its useful lifetime in the radioactive and chemical environment that will be encountered during waste processing. The focus of the work presented in this report is the radiation stability of the CS-100 and the RF resins. The scope of the testing included one test with a sample of the CS-100 resin and testing of two batches of the RF resin (BSC-187 and BSC-210). Samples of the exchangers were irradiated with a {sup 60}Co source to a total ...

1995-09-01

375

Mechanistic studies of ethylene biosynthesis in higher plants  

Energy Technology Data Exchange (ETDEWEB)

Ethylene is a plant hormone that elicits a wide variety of responses in plant tissue. Among these responses are the hastening of abscission, ripening and senescence. In 1979 it was discovered that 1-amino-1-cyclopropane carboxylic acid is the immediate biosynthetic precursor to ethylene. Given the obvious economic significance of ethylene production the authors concentrated their studies on the conversion of ACC to ethylene. They delved into mechanistic aspects of ACC oxidation and they studied potential inhibitors of ethylene forming enzyme (EFE). They synthesized various analogs of ACC and found that EFE shows good stereodiscrimination among alkyl substituted ACC analogs with the 1R, 2S stereoisomer being processed nine times faster than the 1S, 2R isomer in the MeACC series. They also synthesized 2-cyclopropyl ACC which is a good competitive inhibitor of EFE. This compound also causes time dependent loss of EFE activity leading us to believe it is an irreversible inhibitor of ...

1986-01-01

376

High-precision Penning-Trap measurements of light-ion masses  

International Nuclear Information System (INIS)

The UW-Penning Trap Mass Spectrometer (PTMs) is ideally suited for high precision measurements of atomic masses throughout the periodic table upon using highly-stripped ions. However, at the present time, this device has been applied extensively to the light elements ("1H, "2H, "3H, "3He, "4He, "1"2C, "1"3C, "1"4N, "1"6O) due to their fundamental importance. Atomic masses follow immediately from a comparison with some multiply-charged carbon ion, after correcting for the lost electrons and their corresponding binding energies. For instance, the most recent C"5"+/C"6"+ comparison yielded a discrepancy of -0.30(33) ppb, limited only by the magnetic field instability for a 40-h run. The initial emphasis on hydrogen has now produced a 1-ppb value for the proton's atomic mass and similar work with deuterium has yielded a 2.5-ppb value for the neutron's atomic mass. However, the most significant result is the "3H-"3He mass difference = 18,590.1(17) eV which is determined from independent ...

1993-04-12

377

Galactic evolution of D and "3He including stellar production of "3He  

International Nuclear Information System (INIS)

New stellar models which track the production and destruction of "3He (and D) have been evolved for a range of stellar masses (0.65#<=#M/M_c_i_r_c_l_e_-_d_o_t#<=#100), metallicities (0.01#<=#Z/Z_c_i_r_c_l_e_-_d_o_t#<=#1), and initial (main-sequence) "3He mass fractions (10"-"5#<=#X_3_,_M_S#<=#10"-"3). Armed with the "3He yields from these stellar models we have followed the evolution of D and "3He using a variety of chemical evolution models with and without infall of primordial or processed material. Production of new "3He by the lower mass stars overwhelms any reasonable primordial contributions and leads to predicted abundances in the presolar nebula and/or the present interstellar medium in excess of the observationally inferred values. This result, which obtains even for zero primordial D and "3He, and was anticipated by Rood, Steigman, ampersand Tinsley is insensitive to the choice of chemical evolution model; it is driven by the large "3He yields from low-mass ...

378

Formation of silk fibroin nanoparticles in water-miscible organic solvent and their characterization  

Energy Technology Data Exchange (ETDEWEB)

When Silk fibre derived from Bombyx mori, a native biopolymer, was dissolved in highly concentrated neutral salts such as CaCl{sub 2}, the regenerated liquid silk, a gradually degraded peptide mixture of silk fibroin, could be obtained. The silk fibroin nanoparticles were prepared rapidly from the liquid silk by using water-miscible protonic and polar aprotonic organic solvents. The nanoparticles are insoluble but well dispersed and stable in aqueous solution and are globular particles with a range of 35-125 nm in diameter by means of TEM, SEM, AFM and laser sizer. Over one half of the {epsilon}-amino groups exist around the protein nanoparticles by using a trinitrobenzenesulfonic acid (TNBS) method. Raman spectra shows the tyrosine residues on the surface of the globules are more exposed than those on native silk fibers. The crystalline polymorph and conformation transition of the silk nanoparticles from random-coil and {alpha}-helix form (Silk I) into anti-parallel {beta}-sheet form ...

2007-10-15

379

Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction  

Energy Technology Data Exchange (ETDEWEB)

Low-temperature catalytic pretreatment is a promising approach to the development of an improved liquefaction process- This work is a fundamental study on effects of pretreatments on coal structure and reactivity in liquefaction. The main objectives of this project are to study the coal structural changes induced by low-temperature catalytic and thermal pretreatments by using spectroscopic techniques; and to clarify the pretreatment-induced changes in reactivity or convertibility of coals in the subsequent liquefaction. This report describes the recent progress of our work. Substantial progress has been made in the spectroscopic characterization of structure and pretreatment-liquefaction reactions of a Montana subbituminous Coal (DECS-9), and thermochemical analysis of three mw and reacted bituminous coals. Temperature programmed liquefaction has been performed on three low-rank coals both in the presence and absence of dispersed molybdenum sulfide catalyst. We also performed a ...

1992-08-01

380

Depth Profiling of N and C in Ion Implanted ZnO and Si Using Deuterium Induced Nuclear Reaction Analysis  

International Nuclear Information System (INIS)

Nuclear Reaction Analysis (NRA) with deuteron ion beams has been used to probe for ion implanted nitrogen and carbon with high sensitivity in zinc oxide and silicon single crystals. The ion implanted N was measured using 1.4 MeV deuteron ion beams and was found to be in agreement with calculated values. The limit of detection for N in ZnO is 8x1014 ions cm-2. Raman measurements of the ion implanted samples showed three additional modes at 275, 504, and 644 cm-1 compared to the un-implanted ZnO crystals. The NRA and Raman results provided information on the N concentration, depth distribution, and structural changes that occur in dependence on the nitrogen ion fluences. The deuterium induced 12C(d,p)13C reaction was used to measure the carbon impurity/dose in ion implanted silicon. It was found that the use of a large cold shield (liquid nitrogen trap) in the ion implanter chamber greatly reduces the amount of carbon impurity on the surface of ...

2008-11-03

381

Continental-scale magmatic carbon dioxide seepage recorded by dawsonite in the Bowen-Gunnedah-Sydney basin system, eastern Australia  

Energy Technology Data Exchange (ETDEWEB)

Dawsonite, NaAlCO{sub 3}(OH){sub 2}, is widespread as a cement, replacement, and cavity filling in Permo-Triassic sedimentary rocks of the Bowen-Gunnedah-Sydney basin system eastern Australia. The origin of dawsonite in these rocks was studied by petrographic and stable isotope analysis. Dawsonite {delta}{sup 13}C (PDB) values range from {minus}4.0 to +4.1{per_thousand} and are remarkably consistent throughout the Bowen-Gunnedah-Sydney basin system. These values indicate either a marine carbonate or magmatic source for carbon in the dawsonite. A magmatic carbon source is considered more likely on the basis that (1) evidence of and the cause for widespread marine carbonate dissolution in the sedimentary successions are not apparent, (2) dawsonite is widespread in both marine and nonmarine facies, (3) the region has been the site of major igneous activity, (4) other dawsonite deposits of similar carbon isotopic composition are linked to igneous ...

1995-07-03

382

Carbon isotope stratigraphy of the upper Kharaib and Shuaiba formations: Implications for the Early Cretaceous evolution of the Arabian Gulf Region  

Energy Technology Data Exchange (ETDEWEB)

The carbon isotope profiles of shallow-marine carbonates from the Barremian-Aptian Kharaib and Shuaiba formations of the Arabian Gulf region range between 0.5 and 7{per_thousand} {delta}{sup 13}C PDB (Peedee belemnite). Systematic variations can be correlated with isotope profiles reported from Tethyan pelagic limestone sequences. The detailed correspondence between the isotopic signature of the relatively well-dated pelagic limestones and the poorly dated shallow-water limestones from the Arabian Gulf region suggests that global marine carbon isotope changes apparently affected deep-sea and shallow-water carbonate sediments similarly and at a similar time resolution. Although oxygen isotopes have been reset during diagenesis, carbon isotopes appear to have maintained their primary marine signature through time. No evidence has been found to connect carbon isotope trends to subaerial exposure or later meteoric diagenesis. In combination with ...

1996-05-01

383

CO{sub 2} bands in the 3350 - 3700 cm{sup {minus}1} spectral region: Ro-vibrational constants and absolute intensities  

Energy Technology Data Exchange (ETDEWEB)

Spectroscopic constants and absolute intensities from more than 2150 transitions belonging to 52 bands of 7 isotopic species of carbon dioxide have been determined using a multispectrum nonlinear least-squares fitting technique. The spectral data (0.01 cm{sup -1} resolution) were obtained at room temperature and low pressure (<10 Torr) using the McMath-Pierce Fourier transform spectrometer of the National Solar Observatory on Kitt Peak, Arizona. A natural sample of carbon dioxide with absorption path lengths between 24 and 385m were used in recording the spectra. The first measurements have been made of the theoretically predicted 2v{sub 2}{sup 2} 2+v{sub 3} {open_quotes}forbidden{close_quotes} band of {sup 12}CO{sub 2}. Two bands which have not been predicted so far, one belonging to {sup 13}CO{sub 2} and the other to {sup 13}C{sup 16}O{sup 18}O, have been identified. The measured line intensities obtained for each band have been analyzed ...

1995-12-31

384

Antifungal activity of the extracts and neolignans from Piper regnellii (Miq.) C. DC. var. pallescens (C. DC.) Yunck  

Energy Technology Data Exchange (ETDEWEB)

Piper regnellii (Miq.) C. DC. var. pallescens (C. DC.) Yunck (Piperaceae) is a medicinal plant traditionally used in Brazil to treat infectious diseases. The extracts obtained from the leaves of P. regnellii were investigated for their antifungal activities against the yeasts Candida albicans, C. krusei, C. parapsilosis, and C. tropicalis. The EtOAc extract presented gnificant activity against Candida albicans with MIC at 125 {mu}g mL{sup -1}, and a moderate activity against both C. krusei and C. parapsilosis with MIC at 500 {mu}g mL{sup -1}. Candida tropicalis was not inhibited by this extract at concentrations as high as 1000 {mu}g mL{sup -1}. Based on these findings, the EtOAc extract was fractionated by silica gel column chromatography into nine fractions. The hexane and CHCl{sub 3} fractions showed varied levels of antifungal activity against all test yeasts. Further column chromatography separation of the hexane fraction afforded the pure compounds eupomatenoid-6, eupomatenoid-5, ...

2005-11-15

385

Advanced thermally stable jet fuels: Technical progress report, October 1994--December 1994  

Science.gov (United States)

There are five tasks within this project on thermally stable coal-based jet fuels. Progress on each of the tasks is described. Task 1, Investigation of the quantitative degradation chemistry of fuels, has 5 subtasks which are described: Literature review on thermal stability of jet fuels; Pyrolytic and catalytic reactions of potential endothermic fuels: cis- and trans-decalin; Use of site specific {sup 13}C-labeling to examine the thermal stressing of 1-phenylhexane: A case study for the determination of reaction kinetics in complex fuel mixtures versus model compound studies; Estimation of critical temperatures of jet fuels; and Surface effects on deposit formation in a flow reactor system. Under Task 2, Investigation of incipient deposition, the subtask reported is Uncertainty analysis on growth and deposition of particles during heating of coal-derived aviation gas turbine fuels; under Task 3, Characterization of solid gums, sediments, and ...

1995-02-01

386

A zwitterionic silylene as reactive intermediate and its unusual dimerization to an N-heterobicyclic disilane.  

Science.gov (United States)

A way to synthesize the transient zwitterionic silylene L'Si: 8 {L'=CH[(C=CH(2))CMe(N(tBu))(2)]} and achieve its facile dimerization to the remarkable N-heterobicyclic disilane 8(2) is described. At first, employing the beta-diketiminate ligand L [L=CH(CMeN(tBu))(2)], both starting materials LH (2) and its N-lithium salt LLi (3) can react with SiBr(4) to yield the silylene precursor L'SiBr(2) (4) by silicon-induced C-H activation at an exocyclic methyl group on the backbone of the ligand. Compound 4 reacts with SiBr(4) above room temperature to afford the unexpected terminal CH(SiBr(3))-substituted dibromosilane 6 along with the unique tricyclic trisilane 7. Reduction of 4 with KC(8) at 0 degrees C furnishes the novel N-heterobicyclic disilane 8(2), which is a formal dimer of the desired zwitterionic silylene L'Si: (8). It has been reasoned that compound 8(2) may results from [4+1] cycloaddition of two molecules of 8 to give the transient dimer 8(2)', which subsequently undergoes ...

2009-08-01

387

A SURVEY OF MOLECULAR LINES TOWARD MASSIVE CLUMPS IN EARLY EVOLUTIONARY STAGES OF HIGH-MASS STAR FORMATION  

International Nuclear Information System (INIS)

We have observed the CH_3OH J = 2-1, SiO J = 2-1, C"3"4S J = 2-1, H"1"3CO"+ J = 1-0, HN"1"3C J = 1-0, CCH N = 1-0, OCS J = 8-7, and SO J_N = 2_2-1_1 lines toward 20 massive clumps, including Midcourse Space Experiment (MSX) 8 #mu#m dark sources (infrared dark clouds) and MSX 8 #mu#m sources, by using the Nobeyama Radio Observatory 45 m telescope. We have found that the velocity widths of the CH_3OH and C"3"4S lines are broader than those of the H"1"3CO"+ line in the MSX dark sources. On the other hand, they are comparable to the velocity width of the H"1"3CO"+ line in the MSX sources. In addition, the [SiO]/[H"1"3CO"+] abundance ratio is found to be enhanced in the MSX dark sources in comparison with the MSX sources. These results suggest that shocks caused by interaction between an outflow and an ambient dense gas would have substantial impact on the chemical composition of the MSX dark sources. The velocity widths of the CH_3OH and C"3"4S lines relative to that of the H"1"3CO"+ line ...

2010-05-10

388

Regulation of the pT181 encoded tetracycline resistance gene in Straphylococcus aureus  

Energy Technology Data Exchange (ETDEWEB)

pT181 is a naturally-occurring 4437 basepair (bp) plasmid isolated from Staphylococcus aureus which encodes inducible resistance to tetracycline (Tc). The DNA sequence data has identified three open reading frames (ORFs). The largest ORF B, has been found to be responsible for the Tc resistance phenotype of pT181. Since most Tc resistance systems appear to be regulated by an effector protein and a repressor protein, several Bal 31 deletion mutants of pT181 were constructed and analyzed in an effort to identify the elements involved in Tc resistance. Two transcomplementing groups of mutants were identified within the tet gene. The mechanism of Tc resistance was studied by assaying the accumulation of (7-/sup 3/H) Tc by Tc sensitive cells, and uninduced and induced pT181-containing cells. A sharp decrease in accumulation of the drug after an initial increase was observed in Tc induced pT181-containing cells. In vivo labeling of Bacillus subtilis minicells containing pT181 was performed ...

1986-01-01

389

Antimalarial activity of selected Sudanese medicinal plants with emphasis to Maytenus senegalensis  

International Nuclear Information System (INIS)

The aim of the present study is to identify and characterize the antimalrial agents from traitional Sudanese medicinal plants. 49 plants parts representing 26 species from 15 families were extracted and screened for their in vitro antimalrial activity using P. falciparum strain 3D7 which is chloroquine sensitive and Dd2 strain which is chloroquine resistant and pyrimethamine sensitive.The plant species investigated exhibited diverse botanical families. They includes Annonaceae, Aristolochiaceae, Asteraceae, Balantiaceae, Caesalpiniceae, Celasteraceae, Cucurbitaceae, Fabaceae, Graminae, Meliaceae, Myrtaceae, Polygonaceae, Rubiaceae, Rutaceae, and simaroubaceae. The evaluation of these plants for their antimalarial activity and their effect on lymphocyte proliferation was carried out. 57 extracts were tested on the chloroquine sensitive strain (3D7). Where 34 extracts (59%) exhibited significant activity against 3D7 with IC_5_0 values #100 #mu# g/ml), where as Sonochous cornatus, ...

390

mtDNA mutation C1494T, haplogroup A, and hearing loss in Chinese  

British Library Electronic Table of Contents (United Kingdom)

Mutation C1494T in mitochondrial 12S rRNA gene was recently reported in two large Chinese families with aminoglycoside-induced and nonsyndromic hearing loss (AINHL) and was claimed to be pathogenic. This mutation, however, was first reported in a sample from central China in our previous study that was aimed to reconstruct East Asian mtDNA phylogeny. All these three mtDNAs formed a subclade defined by mutation C1494T in mtDNA haplogroup A. It thus seems that mutation C1494T is a haplogroup A-associated mutation and this matrilineal background may contribute a high risk for the penetrance of mutation C1494T in Chinese with AINHL. To test this hypothesis, we first genotyped mutation C1494T in 553 unrelated individuals from three regional Chinese populations and performed an extensive search ...

2006-01-01

391

Tumor necrosis factor-? is associated with positive lymph node status in patients with recurrence of colorectal cancer?indications for anti-TNF-? agents in cancer treatment  

British Library Electronic Table of Contents (United Kingdom)

Introduction The progressive growth of malignancies is accompanied by a decline in the immune response through mechanisms which are poorly understood. Apoptosis and induction of inflammation by tumor released cytokines as tumor escape mechanisms have been proposed to play an important role in colorectal carcinogenesis. Methods Expression of Tumor necrosis factor-alpha (TNF-?) was analyzed in colorectal cancer specimen and the cancer cell line HT-29 by immunohistochemistry and RT-PCR. TNF-? expression on protein and mRNA level were correlated with clinical characteristics and impact on survival. TNFR-1 was co-labelled with TNF-? and CD8+ cytotoxic T cells in immunofluorescence double staining experiments. Results: 94% (n?=?98/104) of the patients with CRC expressed TNF-?. High TNF-? express...

2011-01-01

392

The expression profile of TLR9 mRNA and CpG ODNs immunostimulatory actions in the teleost gilthead seabream points to a major role of lymphocytes  

British Library Electronic Table of Contents (United Kingdom)

Abstract. The potential effects of synthetic unmethylated oligodeoxynucleotides (ODN) containing CpG motifs, mimicking bacterial DNA, has never been evaluated on the immune response in the teleost fish gilthead seabream (Sparus aurata), the most important fish species in Mediterranean aquaculture. First, binding and competition studies have demonstrated that binding is saturated and promiscuous, suggesting the participation of several receptors. Moreover, leucocyte cytotoxic (NCC) activity, production of ROIs (reactive oxygen intermediates), and expression of immune-relevant genes was greatly primed by ODNs. Focusing on the mechanism, the TLR9 gene is widely distributed in seabream tissues and differently regulated in vitro by several stimuli. Moreover, and for the first time in fish, TLR9...

2008-01-01

393

The expression pattern of scygonadin during the ontogenesis of Scylla paramamosain predicting its potential role in reproductive immunity  

British Library Electronic Table of Contents (United Kingdom)

The antimicrobial peptide scygonadin (Scy) was first isolated from the gonad of Scylla serrata and its gene is predominantly expressed in the ejaculatory duct of adult males. Thus, its function was predicted to be associated with reproductive immunity, but this is still unclear and needs further investigation. In our study, the expression pattern of Scy at different developmental stages of both male and female S. paramamosain was investigated, so that the potential function of this peptide could be examined. Using real-time quantitative PCR, Scy mRNA transcripts were demonstrated obviously in the vulnerable embryos and larvae-zoea I but very weakly detected in the larvae-zoea III, megalops and juveniles. The gene expression pattern showed a decreasing trend during the early developmental s...

2011-01-01

394

Sulfation of chitosan oligomers enhances their anti-adipogenic effect in 3T3-L1 adipocytes  

British Library Electronic Table of Contents (United Kingdom)

Inhibition of adipogenesis and lipid accumulation has a very crucial role to prevent obesity. Low molecular weight (LMW) chitosan is known to inhibit fat accumulation and adipogenesis. (N,O)-sulfated chitosan is a sulfation derivative of chitosan oligomers, and its anti-obesity effect is not yet reported. In this study, it has been reported that (N,O)-sulfated chitosan significantly decreased lipid accumulation, an indicator for adipogenesis, in differentiating 3T3-L1 preadipocyte cells. Furthermore, mRNA expressions and protein levels of key adipogenic markers such as peroxisome prolifetor-activated receptor (PPAR)-@c and CCAAT-enhancer binding protein (C/EBP)-@a were considerably decreased by (N,O)-sulfated chitosan treatment. As a consequence, sulfation of LMWC remarkably increased its ...

2011-01-01

395

Purpurin is a key molecule for cell differentiation during the early development of zebrafish retina  

British Library Electronic Table of Contents (United Kingdom)

Recently, we cloned purpurin cDNA as an upregulated gene in the axotomized fish retina. The retina-specific protein was secreted from photoreceptors to ganglion cell layer during an early stage of optic nerve regeneration in zebrafish retina. The purpurin worked as a trigger molecule for axonal regrowth in adult injured fish retina. During zebrafish development, purpurin mRNA first appeared in ventral retina at 2 days post-fertilization (dpf) and spread out to the outer nuclear layer at 3 dpf. Here, we investigated the role of purpurin for zebrafish retinal development using morpholino gene knockdown technique. Injection of purpurin morpholino into the 1-2 cell stage of embryos significantly inhibited the transcriptional and translational expression of purpurin at 3 dpf. In the purpurin mo...

2009-01-01

396

Preliminary crystallographic analysis of a possible transcription factor encoded by the mimivirus L544 gene  

British Library Electronic Table of Contents (United Kingdom)

Mimivirus is the prototype of a new family (the Mimiviridae) of nucleocytoplasmic large DNA viruses (NCLDVs), which already include the Poxviridae, Iridoviridae, Phycodnaviridae and Asfarviridae. Mimivirus specifically replicates in cells from the genus Acanthamoeba. Proteomic analysis of purified mimivirus particles revealed the presence of many subunits of the DNA-directed RNA polymerase II complex. A fully functional pre-transcriptional complex appears to be loaded in the virions, allowing mimivirus to initiate transcription within the host cytoplasm immediately upon infection independently of the host nuclear apparatus. To fully understand this process, a systematic study of mimivirus proteins that are predicted (by bioinformatics) or suspected (by proteomic analysis) to be involved in...

2011-01-01

397

Molecular prospecting for cryptic species in Phyllodistomum lacustri (Platyhelminthes, Gorgoderidae)  

British Library Electronic Table of Contents (United Kingdom)

Rosas-Valdez, R., Choudhury, A. & Prez-Ponce de Len, G. (2011). Molecular prospecting for cryptic species in Phyllodistomum lacustri (Platyhelminthes, Gorgoderidae). -Zoologica Scripta, 40, 296-305. Partial sequences of the 28S ribosomal RNA and cytochrome c oxidase I (COI) genes were compared among populations of a widely distributed and morphologically uniform digenean species in North America, Phyllodistomum lacustri, a parasite characteristically associated with ictalurid catfishes. Specimens were collected from the urinary bladder of ictalurid hosts in six localities of North America, spanning most of the latitudinal range of this freshwater fish group. Sequences of other congeneric species, including a potentially close relative, P.-staffordi, were also obtained and used for comparis...

2011-01-01

398

Molecular phylogenetic relationships and phenotypic diversity in miniaturized toadlets, genus Brachycephalus (Amphibia: Anura: Brachycephalidae)  

British Library Electronic Table of Contents (United Kingdom)

Toadlets of the genus Brachycephalus are endemic to the Atlantic rainforests of southeastern and southern Brazil. The 14 species currently described have snout-vent lengths less than 18mm and are thought to have evolved through miniaturization: an evolutionary process leading to an extremely small adult body size. Here, we present the first comprehensive phylogenetic analysis for Brachycephalus, using a multilocus approach based on two nuclear (Rag-1 and Tyr) and three mitochondrial (Cyt b, 12S, and 16S rRNA) gene regions. Phylogenetic relationships were inferred using a partitioned Bayesian analysis of concatenated sequences and the hierarchical Bayesian method (BEST) that estimates species trees based on the multispecies coalescent model. Individual gene trees showed conflict and also va...

2011-01-01

399

Methanogen community structure in the rumens of farmed sheep, cattle and red deer fed different diets  

British Library Electronic Table of Contents (United Kingdom)

Abstract Development of inhibitors and vaccines that mitigate rumen-derived methane by targeting methanogens relies on knowledge of the methanogens present. We investigated the composition of archaeal communities in the rumens of farmed sheep (Ovis aries), cattle (Bos taurus) and red deer (Cervus elaphus) using denaturing gradient gel electrophoresis (DGGE) to generate fingerprints of archaeal 16S rRNA genes. The total archaeal communities were relatively constant across species and diets, and were less variable and less diverse than bacterial communities. There were diet- and ruminant-species-based differences in archaeal community structure, but the same dominant archaea were present in all rumens. These were members of three coherent clades: species related to Methanobrevibacter ruminan...

2011-01-01

400

Mechanism of Dephosphorylation of the SR Protein ASF/SF2 by Protein Phosphatase 1  

British Library Electronic Table of Contents (United Kingdom)

SR proteins are essential splicing factors whose function is controlled by multi-site phosphorylation of a C-terminal domain rich in arginine-serine repeats (RS domain). The protein kinase SRPK1 has been shown to polyphosphorylate the N-terminal portion of the RS domain (RS1) of the SR protein ASF/SF2, a modification that promotes nuclear entry of this splicing factor and engagement in splicing function. Later, dephosphorylation is required for maturation of the spliceosome and other RNA processing steps. While phosphates are attached to RS1 in a sequential manner by SRPK1, little is known about how they are removed. To investigate factors that control dephosphorylation, we monitored region-specific mapping of phosphorylation sites in ASF/SF2 as a function of the protein phosphatase PP1. W...

2010-01-01

401

Involvement of the Tpl-2/cot oncogene in MMTV tumorigenesis.  

Science.gov (United States)

We report for the first time a relationship between the Tpl-2/cot oncogene and Mouse Mammary Tumor Virus (MMTV) associated transformation of mammary gland cells. A sub-genomic library generated from a primary mammary gland tumor yielded a novel MMTV integration site which disrupted the Tpl-2/cot proto-oncogene between exons 7 and 8. Comparison of a cell line derived from normal mammary gland (comma-D) and a cell line established from an MMTV induced mammary tumor (GR) demonstrated similar rearrangements within Tpl-2/cot for the GR cells but not in the comma-D cells. These rearrangements in the cell line were accompanied by an increase in the level of Tpl-2/cot specific mRNA. This data suggests that Tpl-2/cot expression may be important in epithelial cell transformation or tumor progression. PMID:8934549

1996-11-01

402

Inhibition of the heterotetrameric K++ channel KCNQ1/KCNE1 by the AMP-activated protein kinase  

British Library Electronic Table of Contents (United Kingdom)

Abstract The heterotetrameric K++-channel KCNQ1/KCNE1 is expressed in heart, skeletal muscle, liver and several epithelia including the renal proximal tubule. In the heart, it contributes to the repolarization of cardiomyocytes. The repolarization is impaired in ischemia. Ischemia stimulates the AMP-activated protein kinase (AMPK), a serine/threonine kinase, sensing energy depletion and stimulating several cellular mechanisms to enhance energy production and to limit energy utilization. AMPK has previously been shown to downregulate the epithelial Na++ channel ENaC, an effect mediated by the ubiquitin ligase Nedd4-2. The present study explored whether AMPK regulates KCNQ1/KCNE1. To this end, cRNA encoding KCNQ1/KCNE1 was injected into Xenopus oocytes with and without additional injection o...

2011-01-01

403

Inhibition of heat shock protein 27 (HspB1) tumorigenic functions by peptide aptamers  

British Library Electronic Table of Contents (United Kingdom)

Human heat shock protein 27 (Hsp27, HspB1) is an anti-apoptotic protein characterized for its tumorigenic and metastatic properties, and now referenced as a major therapeutic target in many types of cancer. Hsp27 biochemical properties rely on a structural oligomeric and dynamic organization. Downregulation by small interfering RNA or inhibition with dominant-negative mutant have proven their efficiency to counteract the anti-apoptotic and protective properties of Hsp27. In this study, we report the isolation and characterization of Hsp27-targeted molecules interfering with its structural organization. Using the peptide aptamer (PA) strategy, we isolated PAs that specifically interact with Hsp27 and not with the other members of the small heat shock protein family. In mammalian cell cultur...

2011-01-01

404

Identification of mutations leading to the Lesch-Nyhan syndrome by automated direct DNA sequencing of in vitro amplified cDNA  

Energy Technology Data Exchange (ETDEWEB)

The Lesch-Nyhan (LN) syndrome is a severe X chromosome-linked disease that results from a deficiency of the purine salvage enzyme hypoxanthine phosphoribosyltransferase (HPRT). The mutations leading to the disease are heterogeneous and frequently arise as de novo events. The authors have identified nucleotide alterations in 15 independently arising HPRT-deficiency cases by direct DNA sequencing of in vitro amplified HPRT cDNA. They also demonstrate that the direct DNA sequence analysis can be automated, further simplifying the detection of new mutations at this locus. The mutations include DNA base substitutions, small DNA deletions, a single DNA base insertion, and errors in RNA splicing. The application of these procedures allows DNA diagnosis and carrier identification by the direct detection of the mutant alleles within individual families affected by LN.

1989-03-01

405

Identification of AFAP1L1 as a prognostic marker for spindle cell sarcomas  

British Library Electronic Table of Contents (United Kingdom)

Spindle cell sarcomas consist of tumors with different biological features, of which distant metastasis is the most ominous sign for a poor prognosis. However, metastasis is difficult to predict on the basis of current histopathological analyses. We have identified actin filament-associated protein 1-like 1 (AFAP1L1) as a candidate for a metastasis-predicting marker from the gene expression profiles of 65 spindle cell sarcomas. A multivariate analysis determined that AFAP1L1 was an independent factor for predicting the occurrence of distant metastasis (P=0.0001), which was further confirmed in another set of 41 tumors by a quantitative mRNA expression analysis. Immunohistochemical staining using paraffin-embedded tumor tissues revealed that the metastasis-free rate was significantly better...

2011-01-01

406

Gene expression analysis identifies potential biomarkers of phenanthrene in human hepatocytes (HepG2)  

British Library Electronic Table of Contents (United Kingdom)

Polycyclic aromatic hydrocarbons (PAHs) are ubiquious in the environment both as natural products and as environmental contaminants. Among PAHs, phenanthrene (PH) that is ubiquitously distributed throughout the environment was subjected in this study. Although environmental distribution and metabolism of PH have been well reported, there are only a few studies examined the expression of mRNA and their functions on PH-induced toxicity. A new paradigm in toxicity screening, toxicogenomic technology represents a useful approach for evaluating the toxic properties of environmental pollutants. In this respect, we elicited the genes which were changed more than 2-fold by analysis of gene expression profiles in human hepatocellular carcinoma (HepG2) cells, exposed to PH by using human oligonucleo...

2011-01-01

407

Gene Regulation of Extracellular Matrix Remodeling in Human Bone Marrow Stem Cell-Seeded Tissue-Engineered Grafts  

British Library Electronic Table of Contents (United Kingdom)

Tissue-engineered heart valves are prone to early structural deterioration. We hypothesize that cell?scaffold interaction and mechanical deformation results in upregulation of genes related to osteogenic/chondrogenic differentiation and thus changes extracellular matrix (ECM) composition in human bone marrow mesenchymal stem cell (hBMSC)-derived tissue-engineered grafts. hBMSC were expanded and seeded onto poly-glycolic acid/poly-lactic acid scaffold for 14 days. Seeded tissue-engineered constructs (TEC) were subjected to cyclic flexure for 24?h, whereas control TEC was maintained in roller bottles for the same duration. hBMSC, TEC, and mechanically deformed TEC were subjected to gene-array and histological analysis. Expression levels of RNA and/or protein markers related to chondrogenesis...

2011-01-01

408

Functional adaptation of microbial communities from jet fuel-contaminated soil under bioremediation treatment: simulation of pollutant rebound  

British Library Electronic Table of Contents (United Kingdom)

Abstract To investigate the link between the functionality and the diversity of microbial communities under strong selective pressure from pollutants, two types of mesocosms that simulate natural attenuation and phytoremediation were generated using soil from a site highly contaminated with jet fuel and under air-sparging treatment. An increase in the petroleum hydrocarbon concentration from 4900 to 18-500-mg-kg-1-dw soil simulated a pollutant rebound (postremediation pollutant reversal due to residual contamination). Analysis of soil bacterial communities by denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments showed stronger changes and selection for a phylogenetically diverse microbial population in the mesocosms with pollutant-tolerant willow trees. Enumerat...

2011-01-01

409

Efficient methodologies for sensitive HIV-1 RNA quantitation from plasma and vaginal secretions  

British Library Electronic Table of Contents (United Kingdom)

Background: Quantifying HIV levels in mucosal secretions is essential to study compartmentalized expression of HIV and facilitate development of intervention strategies to prevent disease progression and transmission. Objectives: To develop a sensitive, reliable, and cost-effective technique to quantify HIV from blood and vaginal secretions that is compatible with efficient implementation in clinical research environments. Study design: A sensitive, reliable, internally-controlled real-time reverse transcriptase (RT) PCR assay, which uses the HIV-1 pol gene as a target (Hpol assay) was developed to quantify HIV levels in plasma and genital secretions, and compared to the widely used Roche Amplicor(TM) HIV-1 Monitor assay. In addition, a simplified method of sample collection and processing...

2009-01-01

410

Effect of postharvest water deficit stress on gene expression in heads of broccoli (Brassica oleracea var. italica)  

British Library Electronic Table of Contents (United Kingdom)

Harvested plant organs such as heads of broccoli (Brassica oleracea L. var. italica) experience a range of stresses that can lead to premature reduction in quality and eventual senescence. Understanding plant responses to stress may open up novel opportunities to extend postharvest life. One of the first stresses experienced by harvested organs is likely to be water deficit stress since severance of the vascular system halts the normal flux of water into the tissue. For broccoli branchlets with their cut ends held in water, transcriptome analysis based on hybridization of broccoli floret mRNA to a heterologous Arabidopsis microarray revealed that the transcript abundance of 431 genes reliably changed within 48h of harvest. Of these, transcripts of 146 genes increased and 34 genes decreased...

2011-01-01

411

Carbohydrates/nucleosides/RNA-DNA-ligand interactions  

Energy Technology Data Exchange (ETDEWEB)

Carbohydrate and nucleotide structural determination using modern spectroscopic techniques is dependent on our ability to label oligonucleotides and oligosaccharides with stable isotopes. Uniform Carbon 13 and Nitrogen 15 labeling of oligonucleotides is important to present-day efforts, which are focused on determining the structure of relatively small oligosaccharides and oligonucleotides, which form the elements of larger structures. Because of the relatively recent interest in three-dimensional structure, the development of techniques used to label them has lagged behind parallel techniques used to label peptides and proteins. Therefore, this group`s discussion focused primarily on problems faced today in obtaining oligonucleotides labeled uniformly with carbon 13 and nitrogen 15.

1994-12-01

412

A Hypothesis: Supplementation with Mushroom-Derived Active Compound Modulates Immunity and Increases Survival in Response to Influenza Virus (H1N1) Infection.  

Science.gov (United States)

We hypothesize that the mushroom-derived active compound may be a potential strategy for increasing survival in response to influenza virus (H1N1) infection through the stimulation of host innate immune response. The validity of the hypothesis can be tested by immune response to influenza infection as seen through survival percentage, virus clearance, weight loss, natural killer cell cytotoxicity, Tumor Necrosis Factor-? (TNF-?) and Interferon-gamma (IFN-?) levels, lytic efficiency in the spleens of mice and inducible nitric oxide synthase mRNA expressions in RAW 264.7 murine macrophage cells. The hypothesis may improve people's quality of life, reduce the medical cost of our healthcare system and eliminate people's fears of influenza outbreak. PMID:21660092

2011-03-20

413

Solution conformations of CaCl sub 2 and Ca(NO sub 3 ) sub 2 complexes of chiral tetramethyl 18-crown-6 macrocycles: A 1D and 2D sup 1 H and sup 13 C NMR investigation  

Energy Technology Data Exchange (ETDEWEB)

One- and two-dimensional NMR techniques have been used to investigate the solution structures of (2S,6S,11S,15S)-2,6,11,15-tetramethyl-1,4,7,10,13,16-hexaoxacyclooctadecane (I) and (2R,3R,11R,12R)-2,3,11,12-tetramethyl-1,4,7,10,13,16-hexaoxyacyclooctadecane (II) macrocycle complexes of CaCl{sub 2} and Ca(NO{sub 3}){sub 2} in CDCl{sub 3}. Previous chiroptical studies of these and similar crown complexes by circularly polarized luminescence (CPL), total luminescence (TL), and circular dichroism (CD) spectroscopy have shown that the macrocycle asymmetric carbons in these complexes constrain the ring such that the sense of the ring twist in the S chiral ring complexes is opposite to that in the R chiral ring complexes. These studies have also shown that there is an added chirality element in the di- and trivalent (alkaline earth and lanthanide metal, respectively) nitrate complexes of I and II associated with the twist of the nitrate anions relative to one another as they sterically ...

1989-10-04

414

Recommended ingestion of indispensable amino acids to young men . A study using stable isotopes, plasmatic amino acids and nitrogen balance  

International Nuclear Information System (INIS)

It has been previously stated that the minimum physiological recommendations for the indispensable amino acids in health adults, as proposed by FAO/WHO/UNU in 1985, are far too low, except for the methionine. An amino acid stable isotopic kinetic study was conducted to seek further experimental support to this hypothesis. Twenty healthy young men received an l-amino acid based diet, supplying 140 mg N.kg"-"1.d"-"1, patterned on egg protein for 1 week, then for 3 weeks either i) a pattern based on current international recommendations (FAO diet, n=7), ii) a the tentative Laboratory of Human Nutrition of the Massachusetts Institute of Technology, new amino acid recommendation pattern (MIT diet, n=7) or iii) again the egg hen pattern (EGG diet, n=6). All subjects were again studied for one final, consecutive week of the egg diet. At the end of the initial week, at the first and third week with the three experimental diets,and after three days following the return of the egg diet, an 8 h ...

415

Single protein omission reconstitution studies of tetracycline binding to the 30S subunit of Escherichia coli ribosomes  

Energy Technology Data Exchange (ETDEWEB)

In previous work the authors showed that on photolysis of Escherichia coli ribosomes in the presence of ({sup 3}H)tetracycline (TC) the major protein labeled is S7, and they presented strong evidence that such labeling takes place from a high-affinity site related to the inhibitory action of TC. In this work they use single protein omission reconstitution (SPORE) experiments to identify those proteins that are important for high-affinity TC binding to the 30S subunit, as measured by both cosedimentation and filter binding assays. With respect to both sedimentation coefficients and relative Phe-tRNA{sup Phe} binding, the properties of the SPORE particles they obtain parallel very closely those measured earlier, with the exception of the SPORE particle lacking S13. A total of five proteins, S3, S7, S8, S14, and S19, are shown to be important for TC binding, with the largest effects seen on omission of proteins S7 and S14. Determination of the protein compositions of ...

1990-06-05

416

Regulation of the Low Dose Radiation Paracrine-Specific Anchorage-Independent Growth Response by Annexin A2  

Energy Technology Data Exchange (ETDEWEB)

ABSTRACT-Here we identify release of annexin A2 into the culture medium in response to low dose X-ray radiation exposure and establish functional linkages to an established paracrine factor-mediated anchorage-independent growth response. Using a standard bicameral coculture model, we observe that annexin A2 levels associated with non-irradiated neighboring cells seeded in the lower chamber (annexin A2 silenced [shRNA] JB6 cells) are increased upon coculture with irradiated (10-50 cGy) JB6 cells seeded in the upper chamber, relative to coculture with sham exposed JB6 cells seeded in the upper chamber, suggesting that annexin A2 released into the medium is capable of communicating in a paracrine fashion. Using a previously established coculture model, we observed that the paracrine factor-mediated anchorage-independent growth response to low dose X-ray radiation is markedly reduced when irradiated annexin A2 silenced (shRNA) JB6 cells are used, ...

2009-07-13

417

Molecular cloning, characterization, and expression of human ADP-ribosylation factors: Two guanine nucleotide-dependent activators of cholera toxin  

International Nuclear Information System (INIS)

ADP-ribosylation factors (ARFs) are small guanine nucleotide-binding proteins that enhance the enzymatic activities of cholera toxin. Two ARF cDNAs, ARF1 and ARF3, were cloned from a human cerebellum library. Based on deduced amino acid sequences and patterns of hybridization of cDNA and oligonucleotide probes with mammalian brain poly(A)"+ RNA, human ARF1 is the homologue of bovine ARF1. Human ARF3, which differs from bovine ARF1 and bovine ARF2, appears to represent a newly identified third type of ARF. Hybridization patterns of human ARF cDNA and clone-specific oligonucleotides with poly(A)"+ RNA are consistent with the presence of at least two, and perhaps four, separate ARF messages in human brain. In vitro translation of ARF1, ARF2, and ARF3 produced proteins that behaved, by SDS/PAGE, similar to a purified soluble brain ARF. Deduced amino acid sequences of human ARF1 and ARF3 contain regions, similar to those in other G proteins, that ...

1989-01-01

418

Impact of diisobutyl phthalate and other PPAR agonists on steroidogenesis and plasma insulin and leptin levels in fetal rats  

International Nuclear Information System (INIS)

Endocrine disrupting chemicals can induce malformations and impairment of reproductive function in experimental animals and may have similar effects in humans. Recently, the environmental obesogen hypothesis was proposed, suggesting that environmental chemicals contribute to the development of obesity and insulin resistance. These effects could be related to chemical interaction with nuclear receptors such as the peroxisome proliferator activated receptors (PPARs). As several testosterone-reducing drugs are PPAR activators, we aimed to examine whether four PPAR agonists were able to affect fetal testosterone production and masculinization of rats. Additionally, we wished to examine whether these chemicals affected fetal plasma levels of insulin and leptin, which play important roles in the developmental programming of the metabolic system. Pregnant Wistar rats were exposed from gestation day (GD) 7-21 to diisobutyl phthalate (DiBP), butylparaben, perfluorooctanoate, or rosiglitazone ...

2008-09-04

419

IL-4/Stat6 activities correlate with apoptosis and metastasis in colon cancer cells  

International Nuclear Information System (INIS)

IL-4-induced Stat6 signaling is active in a variety of cell types and plays a role in cell proliferation/growth and resistance to apoptosis. Using EMSA, we identified differential IL-4/Stat6 activities in colorectal cancer cell lines, HT-29 being active Stat6"h"i"g"h phenotype and Caco-2 being defective Stat6"n"u"l"l phenotype, respectively. Active Stat6"h"i"g"h HT-29 cells exhibited resistance to apoptosis by flowcytometry and aggressive metastasis by Transwell assay compared with defective Stat6"n"u"l"l Caco-2 cells. Comparing one another using RT-PCR, Stat6"h"i"g"h HT-29 cells expressed more mRNA of anti-apoptotic and pro-metastatic genes Survivin, MDM2, and TMPRSS4, while Stat6"n"u"l"l Caco-2 cells expressed more mRNA of pro-apoptotic and anti-metastatic genes BAX, CAV1, and P53, respectively. This is the first study describing correlations of IL-4/Stat6 activities with apoptosis and metastasis in colon cancer. These findings, together with ...

2008-05-02

420

Deficiency of the housekeeping gene hypoxanthine-guanine phosphoribosyltransferase (HPRT) dysregulates neurogenesis.  

Science.gov (United States)

Neuronal transcription factors play vital roles in the specification and development of neurons, including dopaminergic (DA) neurons. Mutations in the gene encoding the purine biosynthetic enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) cause the resulting intractable and largely untreatable neurological impairment of Lesch-Nyhan disease (LND). The disorder is associated with a defect in basal ganglia DA pathways. The mechanisms connecting the purine metabolic defect and the central nervous system (CNS) phenotype are poorly understood but have been presumed to reflect a developmental defect of DA neurons. We have examined the effect of HPRT deficiency on the differentiation of neurons in the well-established human (NT2) embryonic carcinoma neurogenesis model. We have used a retrovirus expressing a small hairpin RNA (shRNA) to knock down HPRT gene expression and have examined the expression of a number of transcription factors ...

2009-08-11

421

Clofibrate-induced cytochrome P450-lauric acid omega hydroxylase(P450LA omega):purification, cDNA cloning, sequence and regulation  

Energy Technology Data Exchange (ETDEWEB)

A cytochrome P450 that hydroxylates lauric acid at the 12 position (P450LA omega) was isolated from liver microsomes of clofibrate treated rats. P450LA omega was immunologically distinct from P450s a,b,c,d,e,f,g,h,j,PB1, and PCN1. Polyclonal antibody against P450LA omega was utilized to screen a gt11 cDNA library. A clone (pP450LA omega), was isolated and its sequence determined. The P450LA omega mRNA is a minimum 2387 nts in length and codes for a P450 of Mr.58,222 daltons. This protein shares less than 35% amino acid similarity with P450s b,c,d,e,f,PB1, and PCN1; however, it does contain a hydrophobic amino terminal peptide and a conserved sequence surrounding the Cys residue at position 456, which is similar to other microsomal P450s. P450LA omega is present at high levels in untreated rat kidney and is induced by clofibrate in both kidney and liver. This induction is the result of an accumulation of mRNA through a rapid transcriptional ...

1986-05-01

422

Alteration of nucleoside diphosphate binding specificity of E. coli elongation factor Tu (EF-Tu) by single amino acid substitution at position 138  

International Nuclear Information System (INIS)

A single amino acid substitution (Asp #-># Asn) at position 138 of E. coli EF-Tu was induced in the tufA gene by an M13 phage oligonucleotide site-directed mutagenesis protocol. The mutated tufA gene was then subcloned in a plasmid vector and expressed in maxicells. The properties of ["3"5S]methionine labelled mutant and wild type EF-Tu's were compared by in vitro assays. Mutant and wild-type EF-Tu's bound EF-Ts with approximately equal affinities. The 138-Asn mutation greatly reduced the protein's affinity for GDP; however, this mutation dramatically increased the proteins affinity for XDP. The mutant protein forms a stable complex with phe-tRNA and XTP, which binds to ribosomes; whereas, it does not form a complex with phe-tRNA and GTP. These results suggest that in EF-Tu x NDP complexes amino acid residue 138 must interact with the substituent on C-2 of the purine ring. Thus in wild-type EF-Tu Asp-138 would H-bond to 2-NH_2 of GDP, and in ...

1987-06-07

423

3-Methyl-3-deazaadenine, a stable isostere of N3-methyl-adenine, is efficiently bypassed by replication in vivo and by transcription in vitro.  

Science.gov (United States)

The goal of the present work was to determine the impact of N3-methyladenine (3-mA), an important lesion generated by many environmental agents and anticancer drugs, on in vivo DNA replication and in vitro RNA transcription. Due to 3-mA chemical instability, the stable isostere 3-methyl-3-deazaadenine (3-m-c(3)A) was site specifically positioned into an oligodeoxynucleotide. The oligomer was, then incorporated into a vector system that is rapidly converted to ssDNA inside yeast cells and requires DNA replication opposite the lesion for plasmid clonal selection. For control purposes, an adenine or a stable apurinic/apyrimidinic (AP)-lesion was placed at the same site. The presence of each lesion in the oligonucleotide was confirmed by MALDI-TOF analysis. Plasmids were then transfected into yeast cells. While the AP-site dramatically reduced plasmid replication in all strains, the 3-m-c(3)A had a slight effect in the rad30 background which significantly increased ...

2011-06-14

424

Synthesis, characterization, and crystal structure of neutral rhenium(V) complexes with S-substituted N{sub 2}S{sub 2} ligands  

Energy Technology Data Exchange (ETDEWEB)

Rhenium is technetium`s third row congener and exhibits many of the chemical properties that technetium displays. Theoretically, a Re-PhAT complex will be isostructural with the {sup 99m}Tc PhAT complexes that have been prepared for use as brain imaging agents. A series of neutral rhenium(V) oxo complexes was synthesized by the reaction of ReOBr{sub 4}{sup {minus}} with diamino-thiol-thioether ligands of the type (RSC(CH{sub 3}){sub 2})CH{sub 2}NH(o-C{sub 6}H{sub 4})NHCH{sub 2}C(CH{sub 3}){sub 2}SH. The complexes were characterized by IR, UV/visible, and {sup 1}H and {sup 13}C NMR spectroscopy and by fast-atom-bombardment mass spectroscopy. The single-crystal X-ray structure determination on two of the complexes, where R = CH{sub 2}CH{double_bond}CH{sub 2} and CH{sub 2}CH{sub 2}-CH{sub 3}, showed them to consist of a square pyramidal Re{sup V}ON{sub 2}S{sub 2} core. ReO[CH{sub 2}{double_bond}CHCH{sub 2}SC(CH{sub 3}){sub 2}CH{sub 2}N(o-C{sub ...

1994-11-23

425

Isotope fractionations and radiocarbon ages of beach rock samples collected from the Nansei Islands, southwest of Japan  

International Nuclear Information System (INIS)

Beach rocks are observed frequently on the tropical and subtropical sandy beaches where they express thin beds dipping seaward at less than 15 degrees. They consist of beach sediments including fossil shells, fragments of corals, diatoms and other biocarbonates, and are well cemented within the inter-tidal zone with calcium carbonate originated in sea water. Therefore, they are not only good indicators which show the past sea level, but also provide good sample material for radiocarbon dating. The locations of beach rocks give us an optimum condition studying a carbon cycle between land and marine environment by analyzing their isotope fractionations. In order to estimate the origin of calcium carbonate which worked as an adhesive when beach rocks were formed and to estimate the formative ages of beach rocks, a total of 330 fossil corals, fossil shells and calcarenite or calcirdite samples were collected from 128 sites of 16 islands consisting of the Nansei Islands, southwest of Japan. ...

2004-10-25

426

Emission of {sup 14}C by the Almirante Alvaro Alberto Nuclear Power Plant 1 and 2 and their local effects on the environmental levels; Emissao de {sup 14}C pelas unidades 1 e 2 da Central Nuclear Almirante Alvaro Alberto (CNAAA) e seu efeito local nos niveis ambientais  

Energy Technology Data Exchange (ETDEWEB)

{sup 14}C is a is a long-lived beta-emitting nuclide (T{sub 1/2} = 5730 years) produced naturally in the upper atmosphere as a result of reactions between neutrons and stable {sup 14}N({sup 14}N(n,p){sup 14}C). Although in a lesser extent, nuclear power plants produce {sup 14}C as well during their routine operation. Since it is converted in {sup 14}CO{sub 2} and mixed throughout the atmosphere, it is incorporated into plant tissues, via photosynthesis process, and hence in food chain. Because of the biological importance of {sup 14}C and long half-life, it is of interest to quantify the amounts released by nuclear industry. The Brazilian nuclear central named Nuclear Central Admiral Alvaro Alberto (CNAAA) has two nuclear reactors of PWR type in operation, Angra I (657 MWe) and Angra II (1350 MWe), and one under construction, Angra III (1309 MWe PWR). The aim of this study was to determine the strength of the sources and the {sup 14}C content in the environment through analyses of air, ...

2006-07-01

427

Study on the variations of molecular structures of some biomolecules induced by free electron laser using FTIR spectroscopy  

International Nuclear Information System (INIS)

In this study, free electron laser (FEL) with selective wavelength was used to induce structure changes of biomolecules, which were characterized by FTIR spectroscopy. For understanding of the interactions between FEL and biomolecules as well as biological tissues, the biomolecules investigated are ATP, ADP, AMP, t-RNA, D-ribose and the complex of SmCl_3-D-ribose. Their FTIR spectra before and after irradiation of FEL show molecular structure variations of the samples after irradiation of FEL, especially the rearrangement of their hydrogen bond networks. Along with the various irradiation wavelengths, irradiation time and molecular structures, the changes after irradiation are different for these molecules. In the FTIR spectra after irradiation, the phenomenon that the bands split into several peaks indicates the existence of several structures, conformations and configurations, which may be prompted by multiple photons process induced by FEL. After irradiation, ...

2007-05-01

428

Roles for Rat Hepatocyte Malignant Transforming Factor (HMTF) in Late Stage of Hepatocarcinogenesis.  

Science.gov (United States)

In a previous study, to identify genes of importance for hepatocellular carcinogenesis, and especially for processes involved in malignant transformation, the authors investigated differences in gene expression between adenomas and carcinomas by DNA microarray. In the present study, the authors investigated AW434047, one of the sequences that was upregulated in carcinomas. The investigation led to the identification of a novel gene, which the authors named hepatocyte malignant transforming factor (HMTF), of unknown function whose expression was increased in hepatocellular carcinomas. Northern blot and in situ hybridization also demonstrated high levels of HMTF in rat hepatocellular carcinoma (HCC) cell lines, lymphocytes in the spleen, colon mucosal epithelia, spermatocytes, and granule cells of the hippocampus. Reduction of HMTF by RNA interference (RNAi) in N1 cells, an HCC cell line, caused suppression of cell proliferation, invasion, and migration. Suppression ...

2011-09-20

429

Report on a survey in fiscal 1999. Survey on industrial utilization of microorganism reaction mechanisms under anaerobic condition; 1999 nendo kenki jokenka ni okeru biseibutsu hanno kiko no kogyoteki riyo ni kansuru chosa hokokusho  

Energy Technology Data Exchange (ETDEWEB)

Industrial utilization of reaction mechanisms of microorganisms under anaerobic condition permits structuring energy saving type production processes. The present survey has investigated features of new microorganisms under anaerobic condition and the status of researches thereon inside and outside the country, and discussed their future applications. Chapter 1 compares anaerobic microorganisms and functions of microorganism under anaerobic condition with those aerobic to describe their general features, and describes the purpose of this survey and the summary of the investigations. Chapter 2 surveys the current status of technologies to utilize microorganisms under anaerobic condition. Chapter 3 outlines metabolic characteristics of the anaerobic microorganisms, and extracts functions effective for material production by different anaerobic microorganisms to describe their applicability. Chapter 4 evaluates the system classification for the anaerobic microorganisms utilizing the basic ...

2000-03-01

430

Regulation by small RNAs via coupled degradation: mean-field and variational approaches  

CERN Document Server

Regulatory genes called small RNAs (sRNAs) are known to play critical roles in cellular responses to changing environments. For several sRNAs, regulation is effected by coupled stoichiometric degradation with messenger RNAs (mRNAs). The nonlinearity inherent in this regulatory scheme indicates that exact analytical solutions for the corresponding stochastic models are intractable. Here, we present a variational approach to analyze a well-studied stochastic model for regulation by sRNAs via coupled degradation. The proposed approach is efficient and provides accurate estimates of mean mRNA levels as well as higher order terms. Results from the variational ansatz are in excellent agreement with data from stochastic simulations for a wide range of parameters, including regions of parameter space where mean-field approaches break down. The proposed approach can be applied to quantitatively model stochastic gene expression in complex regulatory networks.

2011-01-01

431

Poncirin promotes osteoblast differentiation but inhibits adipocyte differentiation in mesenchymal stem cells.  

Science.gov (United States)

Poncirin, flavanone glycoside, isolated from the fruit of Poncirus trifoliata, has anti-bacterial and anti-inflammatory activities. In this study, the effects of poncirin on the differentiation of mesenchymal stem cells were investigated. The C3H10T1/2 mesenchymal stem cells and primary bone marrow mesenchymal stem cells were studied. In the C3H10T1/2 cells, poncirin prevented adipocyte differentiation, as demonstrated by inhibition of cytoplasm lipid droplet accumulation and peroxisome proliferator-activating receptor-? (PPAR-?) and CCAAT-enhancer-binding protein-? (C/EBP-?) mRNA expression. By contrast, poncirin enhanced the expression of the key osteogenic transcription factors, runt-related transcription factor 2 (Runx2) and transcriptional coactivator with PDZ-binding motif (TAZ). Poncirin also enhanced expression of the osteogenic marker genes including alkaline phosphatase (ALP) and osteocalcin (OC). Poncirin increased mineral nodule formation in primary ...

2011-05-01

432

Nuclear Targeting of Methyl-Recycling Enzymes in Arabidopsis thaliana Is Mediated by Specific Protein Interactions.  

Science.gov (United States)

Numerous transmethylation reactions are required for normal plant growth and development. S-adenosylhomocysteine hydrolase (SAHH) and adenosine kinase (ADK) act coordinately to recycle the by-product of these reactions, S-adenosylhomocysteine (SAH) that would otherwise competitively inhibit methyltransferase (MT) activities. Here, we report on investigations to understand how the SAH produced in the nucleus is metabolized by SAHH and ADK. Localization analyses using green fluorescent fusion proteins demonstrated that both enzymes are capable of localizing to the cytoplasm and the nucleus, although no obvious nuclear localization signal was found in their sequences. Deletion analysis revealed that a 41-amino-acid segment of SAHH (Gly(150)-Lys(190)) is required for nuclear targeting of this enzyme. This segment is surface exposed, shows unique sequence conservation patterns in plant SAHHs, and possesses additional features of protein-protein interaction motifs. ADK and SAHH interact in ...

2011-10-01

433

K"A"T"P channels in mesenchymal stromal stem cells: Strong up-regulation of Kir6.2 subunits upon osteogenic differentiation  

British Library Electronic Table of Contents (United Kingdom)

The promising use of mesenchymal stromal cells (MSC) in regenerative technologies accounts for necessity of detailed study of their physiology. Proliferation and differentiation of multipotent cells often involve changes in their metabolic state. In the present study, we analyzed the expression of ATP-sensitive potassium (K"A"T"P) channels in MSC and upon in vitro differentiation. K"A"T"P channels are present in many cells and regulate a variety of cellular functions by coupling cell metabolism with membrane potential. Kir6.1, Kir6.2 and SUR2A were expressed in undifferentiated MSC, whereas SUR2B and SUR1 were not detected on cDNA and protein level. Upon adipogenic differentiation Kir6.1 and SUR2A showed a significant reduction of the amount of mRNA by 84% and 95%, respectively, whereas Ki...

2011-01-01

434

Inhibitory effect of minocycline on osteoclastogenesis in mouse bone marrow cells  

British Library Electronic Table of Contents (United Kingdom)

Objective: To study the effects of minocycline hydrochloride (MINO) on the formation of tartrate-resistant acid phosphatase (TRAP) staining-positive multinucleated osteoclast-like cells in mouse bone marrow cells (BMCs) treated with 1@a,25(OH)"2D"3 or soluble receptor activator of nuclear factor-@kB ligand (s-RANKL). Materials and methods: Mouse BMCs were cultured in alpha-modified minimum essential medium containing foetal calf serum (10%) and tetracyclines (2.5, 5 and 10@mM), such as MINO, tetracycline hydrochloride (TC), oxytetracycline hydrochloride (OXT) or doxycycline (DOXY) in the presence of 1@a,25(OH)"2D"3 (10nM) or s-RANKL (20ng/ml) for 7 days, and the number of TRAP staining-positive osteoclast-like cells was counted. In RNA isolated from BMCs treated with 1@a,25(OH)"2D"3 or s-R...

2011-01-01

435

Identification of three related human GRO genes encoding cytokine functions  

International Nuclear Information System (INIS)

The product of the human GRO gene is a cytokine with inflammatory and growth-regulatory properties; GRO is also called MGSA for melanoma growth-stimulatory activity. The authors have identified two additional genes, GRO#beta# and GRO#gamma#, that share 90% and 86% identity at the deduced amino acid level with the original GRO#alpha# isolate. One amino acid substitution of proline in GRO#alpha# by leucine in GRO#beta# and GRO#gamma# leads to a large predicted change in protein conformation. Significant differences also exist in the 3' untranslated region, including different numbers of ATTTA repeats associated with mRNA instability. A 122-base-pair region in the 3' region is conserved among the three GRO genes, and a part of it is also conserved in the Chinese hamster genome, suggesting a role in regulation. DNA hybridization with oligonucleotide probes and partial sequence analysis of the genomic clones confirm that the three forms are derived from related but ...

436

Identification of proteins important for tetracycline (TC) binding to ribosomes by single protein omission reconstitution (SPORE) experiments  

Energy Technology Data Exchange (ETDEWEB)

TC inhibits protein synthesis in E. coli by interfering with aminoacyl-tRNA binding to the ribosomal A site, and there is strong evidence that such inhibition results from TC binding to a high affinity site on the 30S subunit. The SPORE approach has been used to define those 30S proteins that are potentially important for high affinity TC binding, measured as the (/sup 3/H)-TC co-sedimenting with the reconstitution particle through a sucrose density gradient. Reverse phase-HPLC has been used both to prepare ribosomal proteins and to analyze the protein content of reconstituted particles. The results obtained so far show that protein S7, as well as some proteins linked to S7 in the 30S assembly map, are important for TC binding, whereas other ribosomal proteins are not. These results are in very good accord with their earlier photoaffinity labeling studies that strongly implicated S7 as forming part of the TC binding site. Interestingly, protein S18, which is ...

1987-05-01

437

Identification of culturable and originally non-culturable endophytic bacteria isolated from shoot tip cultures of banana cv. Grand Naine  

British Library Electronic Table of Contents (United Kingdom)

In this article we describe the identification of endophytic bacteria belonging to three groups isolated from shoot tip cultures of banana cv. Grand Naine in a recent study (Thomas et?al. 2008) based on partial 16S rRNA gene sequence homology analysis. The first group included banana stocks that displayed obvious colony growth on MS based tissue culture medium during the first in?vitro passage. The second group constituted stocks that were tissue index-negative for cultivable bacteria initially but turned index-positive after a few to several (4?8) in?vitro passages while the third group formed one sub-stock that turned index-positive after about 18 passages. The organisms belonged to about 20 different genera comprising of ?, ?, ?-proteobacteria, Gram-positive firmicutes and actinobacteri...

2008-01-01

438

Experimental attempt to produce mRNA transfected dendritic cells derived from enriched CD34+ blood progenitor cells  

British Library Electronic Table of Contents (United Kingdom)

It Peripheral blood progenitor enriched CD34+ cells (PBPC) are rather often used as stem cell background in cancer patients following high dose therapy. Keeping in mind that precursor dendritic cells (DCs) originate from haematopoietic progenitor cells, purified CD34+ cells might also serve as starting cells for ex-vivo production of DC. The aim of the present study is to develop a clinical grade procedure for ex-vivo production of DC derived from enriched CD34+ cells. Various concentrations of CD34+ cells were grown in gas-permeable Teflon bags with different serum-free and serum-containing media supplemented with GM-CSF, IL-4, TNF-a, SCF, Flt-3L and INF-a. Serum-free CellGroSCGM medium for 7 days followed by CellGroDC medium in 7 days gave equal results as serum-containing medium. Follow...

2008-01-01

439

Evaluation of the effectiveness of an antimicrobial air filter to avoid porcine reproductive and respiratory syndrome virus (PRRSV) aerosol transmission, after 16 months of exposure to a commercial swine environmental conditions  

Energy Technology Data Exchange (ETDEWEB)

The effectiveness of Noveko's antimicrobial filter was evaluated after 16 months of exposure to commercial swine production. The experiment involved the use of a scaled model of a commercial swine facility consisting of 2 small chambers connected by a duct containing the filters. A 5 kg naive pig was placed in the reception chamber for a period of 6 hours after aerosolization with porcine reproductive and respiratory syndrome virus (PRRSV). Blood samples from pigs were collected before and after aerosolization to test for the presence of PRRSV RNA. Only blood samples were tested for PRRSV antibodies by IDEXX 2XR ELISA. None of the 9 pigs tested were found to be infected. The study showed that the technology used to integrate the antimicrobial agent into the filter fibers allows the filter combination to withstand extreme weather and endure commercial swine production for at least 16 months, and can maintain its effectiveness to avoid airborne transmission ...

2010-07-01

440

Doxycycline up-regulates the expression of IL-6 and GM-CSF via MAPK/ERK and NF-kB pathways in mouse thymic epithelial cells  

British Library Electronic Table of Contents (United Kingdom)

Thymic epithelial cells (TECs) constitute a major component of the thymic stroma which provides a microenvironment critical for developing thymocytes. We have previously demonstrated that doxycycline (Dox), a tetracycline derivative, enhances the proliferation of the mouse thymic epithelial cell line 1 (MTEC1) via MAPK/ERK signal pathway. Herein we provide evidence that Dox also has profound impact on the cytokine production by MTEC1. Specifically, the expression of IL-6 and GM-CSF, both at mRNA and protein levels, was found to be increased in a time- and dose-dependent manner with the addition of Dox. Western blotting analysis revealed that treatment with Dox-induced phosphorylation of the p65 subunit of NF-kB and ERK. Notably, Dox-induced up-regulation of IL-6 and GM-CSF was largely abol...

2011-01-01

441

Does adenine incorporation into nucleic acids measure total microbial production:: a response to comments by Fuhrman et al  

Science.gov (United States)

The uptake and incorporation of (/sup 3/H)adenine as a measure of total microbial (bacteria and unicellular algae) nucleic acid synthesis depends on the validity of several assumptions. A unique characteristic of the (/sup 3/H)adenine method is the ability to measure the specific radioactivity (nCi pmol/sup -1/) of the immediate precursor pool of the adenine incorporated into nucleic acids. This measurement permits correction for isotope dilution when the added radiotracer mixes with exogenous pools of structurally related compounds before uptake and with endogenous pools after transport into the cells. The immediate precursors to (/sup 3/H)adenine incorporation into cellular RNA and DNA are ATP and dATP. Since the intracellular dATP pool is in isotopic equilibrium with the ATP pool, one can determine the specific radioactivity of both precursor pools by measuring that of the intracellular ATP pool. If the specific activity of the precursor pool is not measured, ...

1986-11-01

442

Differentially expressed genes in hypothalamus in relation to genomic regions under selection in two chicken lines resulting from divergent selection for high or low body weight  

British Library Electronic Table of Contents (United Kingdom)

Long-term divergent selection for low or high body weight from the same founder population has generated two extremely divergent lines of chickens, the high- (HWS) and low-weight (LWS) selected lines. At selection age (56?days), the lines differ by more than nine times in body weight. The HWS line chickens are compulsive feeders, whereas in the LWS line, some individuals are anorexic and others have very low appetite. Previous studies have implicated the central nervous system and particularly the hypothalamus in these behavioural differences. Here, we compared the mRNA expression in hypothalamus tissue from chickens on day?4 post-hatch using oligonucleotide arrays and found that the divergent selection had resulted in minor but multiple expression differences. Differentially expressed gen...

2011-01-01

443

Complete genome sequence of Conexibacter woesei type strain (ID131577T)  

Energy Technology Data Exchange (ETDEWEB)

The genus Conexibacter (Monciardini et al. 2003) represents the type genus of the family Conexibacteraceae (Stackebrandt 2005, emend. Zhi et al. 2009) with Conexibacter woesei as the type species of the genus. C. woesei is a representative of a deep evolutionary line of des-cent within the class Actinobacteria. Strain ID131577T was originally isolated from temperate forest soil in Gerenzano (Italy). Cells are small, short rods that are motile by peritrichous fla-gella. They may form aggregates after a longer period of growth and, then as a typical charac-teristic, an undulate structure is formed by self-aggregation of flagella with entangled bacteri-al cells. Here we describe the features of the organism, together with the complete sequence and annotation. The 6,359,369 bp long genome of C. woesei contains 5,950 protein-coding and 48 RNA genes and is part of the Genomic Encyclopedia of Bacteria and Archaea project.

2010-01-01

444

Complete genome sequence of Actinosynnema mirum type strain (101T)  

Energy Technology Data Exchange (ETDEWEB)

Actinosynnema mirum Hasegawa et al. 1978 is the type species of the genus, and is of phylogenetic interest because of its central phylogenetic location in the Actino-synnemataceae, a rapidly growing family within the actinobacterial suborder Pseudo-nocardineae. A. mirum is characterized by its motile spores borne on synnemata and as a producer of nocardicin antibiotics. It is capable of growing aerobically and under a moderate CO2 atmosphere. The strain is a Gram-positive, aerial and substrate mycelium producing bacterium, originally isolated from a grass blade collected from the Raritan River, New Jersey. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first complete genome sequence of a member of the family Actinosynnemataceae, and only the second sequence from the actinobacterial suborder Pseudonocardineae. The 8,248,144 bp long single replicon genome with its 7100 protein-coding and 77 RNA ...

2009-05-20

445

Cloning and sequencing of cDNA encoding human DNA topoisomerase II and localization of the gene to chromosome region 17q21-22  

Energy Technology Data Exchange (ETDEWEB)

Two overlapping cDNA clones encoding human DNA topoisomerase II were identified by two independent methods. In one, a human cDNA library in phage {lambda} was screened by hybridization with a mixed oligonucleotide probe encoding a stretch of seven amino acids found in yeast and Drosophila DNA topoisomerase II; in the other, a different human cDNA library in a {lambda}gt11 expression vector was screened for the expression of antigenic determinants that are recognized by rabbit antibodies specific to human DNA topoisomerase II. The entire coding sequences of the human DNA topoisomerase II gene were determined from these and several additional clones, identified through the use of the cloned human TOP2 gene sequences as probes. Hybridization between the cloned sequences and mRNA and genomic DNA indicates that the human enzyme is encoded by a single-copy gene. The location of the gene was mapped to chromosome 17q21-22 by in situ hybridization of a cloned fragment to ...

1988-10-01

446

Cloning and expression of Drosophila TAFII60 and human TAFII70 reveal conserved interactions with other subunits of TFIID.  

Science.gov (United States)

Regulation of transcription initiation by RNA polymerase II requires TFIID, a multisubunit complex composed of the TATA binding protein (TBP) and at least seven tightly associated factors (TAFs). Some TAFs act as direct targets or coactivators for promoter-specific activators while others serve as interfaces for TAF-TAF interactions. Here, we report the molecular cloning, expression and characterization of Drosophila dTAFII60 and its human homolog, hTAFII70. Recombinant TAFII60/70 binds weakly to TBP and tightly to the largest subunit of TFIID, TAFII250. In the presence of TAFII60/70, TBP and TAFII250, a stable ternary complex is formed. Both the human and Drosophila proteins directly interact with another TFIID subunit, dTAFII40. Our findings reveal that Drosophila TAFII60 and human TAFII70 share a high degree of structural similarity and that their interactions with other subunits of TFIID are conserved.Images

1993-12-15

447

Changes in myocardial beta1-adrenergic receptor and stimulatory G-protein gene expression after chronic treatment with doxorubicin in rat.  

Science.gov (United States)

The gene expression of beta(1)-adrenergic receptor (beta(1)AR) and stimulatory G-protein Gsalpha in ventricle after chronic treatment with doxorubicin (DOX) in rat was investigated. The rats were treated with DOX in a dose of 2.5 mg/kg once a week for 5 weeks, the cumulative dose being 12.5 mg/kg. Two weeks after the last injection, the positive inotropic effect of isoproterenol was noticeably decreased in left atrial muscle preparations isolated from DOX-treated rats. Northern blot hybridization showed that the mRNA transcripts of beta(1)AR and Gsalpha, important signal transduction elements for regulating heart rate and contractility, were significantly decreased in the ventricle of DOX-treated rats. Thus, chronic treatment with DOX decreases the gene expression levels of myocardial beta(1)AR and Gsalpha. PMID:15353854

2004-08-01

448

CHRNA5 as negative regulator of nicotine signaling in normal and cancer bronchial cells: effects on motility, migration and p63 expression  

British Library Electronic Table of Contents (United Kingdom)

Genome-wide association studies have linked lung cancer risk with a region of chromosome 15q25.1 containing CHRNA3, CHRNA5 and CHRNB4 encoding a3, a5 and b4 subunits of nicotinic acetylcholine receptors (nAChR), respectively. One of the strongest associations was observed for a non-silent single-nucleotide polymorphism at codon 398 in CHRNA5. Here, we have used pharmacological (antagonists) or genetic (RNA interference) interventions to modulate the activity of CHRNA5 in non-transformed bronchial cells and in lung cancer cell lines. In both cell types, silencing CHRNA5 or inhibiting receptors containing nAChR a5 with a-conotoxin MII exerted a nicotine-like effect, with increased motility and invasiveness in vitro and increasing calcium influx. The effects on motility were enhanced by addit...

2011-01-01

449

Bip overexpression, but not CHOP inhibition, attenuates fatty-acid-induced endoplasmic reticulum stress and apoptosis in HepG2 liver cells  

British Library Electronic Table of Contents (United Kingdom)

Aims: In this study we investigated whether attenuation of endoplasmic reticulum stress (ER stress) could protect HepG2 cells from free fatty acid (FFA)-induced apoptosis. Main methods: Human liver cell line HepG2 cells were exposed to Sodium Palmitate (Pa) or Sodium Oleate (Ol). Apoptosis and ER stress of HepG2 cells were analyzed with flow cytometry, real-time RT-PCR and Western Blotting. An expression plasmid encoding for the ER chaperone immunoglobulin heavy chain-binding protein (Bip) was transfected into HepG2 cells to attenuate ER stress. Small interfering RNA siCHOP was used to knockdown the expression of C/EBP Homologous Protein (CHOP) in HepG2. Key findings: Pa led to cytotoxicity and apoptosis in HepG2 cells in a dose-dependent pattern and also induced ER stress indicated by inc...

2010-01-01

450

Artesunate in combination with oxacillin protect sepsis model mice challenged with lethal live methicillin-resistant Staphylococcus aureus (MRSA) via its inhibition on proinflammatory cytokines release and enhancement on antibacterial activity of oxacillin  

British Library Electronic Table of Contents (United Kingdom)

Sepsis induced by methicillin-resistant Staphylococcus aureus (MRSA) has worse outcome because of multiresistance to a large group of antibiotics, which may lead to death from septic shock. In the present study, we firstly found that artesunate in combination with oxacillin was capable of protecting mice challenged with live MRSA WHO-2 (WHO-2) and the protection was related to the reduced TNF-a and IL-6 levels and decreased bacterial load. Based on above results, artesunate was further investigated from two aspects in vitro, anti-inflammation effect and antibacterial enhancement effect on antibiotics. Artesunate not only inhibited TNF-a and IL-6 release but also inhibited mRNA and protein expressions of TLR2 and Nod2, two important receptors, in murine peritoneal macrophages stimulated wit...

2011-01-01

451

A single amino acid substitution results in a retinoblastoma protein defective in phosphorylation and oncoprotein binding  

International Nuclear Information System (INIS)

The authors have previously identified a small-cell lung cancer cell line (NCI-H209) that expresses an aberrant, underphosphorylated form of the retinoblastoma protein RB1. Molecular analysis of RB1 mRNA from this cell line revealed a single point mutation within exon 21 that resulted in a nonconservative amino acid substitution (cysteine to phenylalanine) at codon 706. Stable expression of this mutant RB1 cDNA in a human cell line lacking endogenous RB1 demonstrated that this amino acid change was sufficient to inhibit phosphorylation. In addition, this cysteine-to-phenylalanine substitution also resulted in loss of RB1 binding to the simian virus 40 large tumor and adenovirus E1A transforming proteins. These results confirm the importance of exon 21 coding sequences and suggest that the cysteine residue at codon 706 may play a role in achieving a specific protein conformation essential for protein-protein interactions.

452

Two and 8-azido photoaffinity probes. 1. Enzymatic synthesis, characterization, and biological properties of 2- and 8-azido photoprobes of 2-5A and photolabeling of 2-5A binding proteins  

International Nuclear Information System (INIS)

The 2- and 8-azido trimer 5'-triphosphate photoprobes of 2-5A have been enzymatically synthesized from [#gamma#-"3"2P]2-azidoATP and [#alpha#-"3"2P]8-azidoAPT by 2-5A synthetase from rabbit reticulocyte lysates. Identification and structural determination of the 2- and 8-azido adenylate trimer 5'-triphosphates were accomplished by enzymatic hydrolyses with T2 RNase, snake venom phosphodiesterase, and bacterial alkaline phosphatase. Hydrolysis products were identified by HPLC and PEI-cellulose TLC analyses. The 8-azido photoprobe of 2-5A displaces p_3A_4["3"2P]pCp from RNase L with affinity equivalent to p_3A_3. The 8-azido photoprobe also activates RNase L to hydrolyze poly(U)["3"2P]pCp 50% at 7 /times/ 10/sup /minus/9/ M in core-cellulose assays. The 2- and 8-azido photoprobes and authentic p_3A_3 activate RNase L to cleave 28S and 18S rRNA to specific cleavage products at 10/sup /minus/9/ M in rRNA cleavage assays. The nucleotide binding ...

453

Modulation of neuronal differentiation by CD40 isoforms  

International Nuclear Information System (INIS)

Neuron differentiation is a complex process involving various cell-cell interactions, and multiple signaling pathways. We showed previously that CD40 is expressed and functional on mouse and human neurons. In neurons, ligation of CD40 protects against serum withdrawal-induced injury and plays a role in survival and differentiation. CD40 deficient mice display neuron dysfunction, aberrant neuron morphologic changes, and associated gross brain abnormalities. Previous studies by Tone and colleagues suggested that five isoforms of CD40 exist with two predominant isoforms expressed in humans: signal-transducible CD40 type I and a C-terminal truncated, non-signal-transducible CD40 type II. We hypothesized that differential expression of CD40 isoform type I and type II in neurons may modulate neuron differentiation. Results show that adult wild-type, and CD40"-"/"- deficient mice predominantly express CD40 type I and II isoforms. Whereas adult wild-type mice express mostly CD40 type I in ...

2008-05-02

454

Identification and characterization of noncoding small RNAs in Streptococcus pneumoniae serotype 2 strain D39.  

Science.gov (United States)

We report a search for small RNAs (sRNAs) in the low-GC, gram-positive human pathogen Streptococcus pneumoniae. Based on bioinformatic analyses by Livny et al. (J. Livny, A. Brencic, S. Lory, and M. K. Waldor, Nucleic Acids Res. 34:3484-3493, 2006), we tested 40 candidates by Northern blotting and confirmed the expression of nine new and one previously reported (CcnA) sRNAs in strain D39. CcnA is one of five redundant sRNAs reported by Halfmann et al. (A. Halfmann, M. Kovacs, R. Hakenbeck, and R. Bruckner, Mol. Microbiol. 66:110-126, 2007) that are positively controlled by the CiaR response regulator. We characterized 3 of these 14 sRNAs: Spd-sr17 (144 nucleotides [nt]; decreased in stationary phase), Spd-sr37 (80 nt; strongly expressed in all growth phases), and CcnA (93 nt; induced by competence stimulatory peptide). Spd-sr17 and CcnA likely fold into structures containing single-stranded regions between hairpin structures, whereas Spd-sr37 forms a base-paired structure. Primer ...

2010-01-01

455

An ELISA-based high throughput protein truncation test for inherited breast cancer  

Science.gov (United States)

IntroductionBreast cancer is the most diagnosed and second leading cause of cancer deaths in the U.S. female population. An estimated 5 to 10 percent of all breast cancers are inherited, caused by mutations in the breast cancer susceptibility genes (BRCA1/2). As many as 90% of all mutations are nonsense mutations, causing a truncated polypeptide product. A popular and low cost method of mutation detection has been the protein truncation test (PTT), where target regions of BRCA1/2 are PCR amplified, transcribed/translated in a cell-free protein synthesis system and analyzed for truncated polypeptides by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and autoradiography. We previously reported a novel High Throughput Solid-Phase PTT (HTS-PTT) based on an enzyme-linked immunosorbent assay (ELISA) format that eliminates the need for radioactivity, SDS-PAGE and subjective interpretation of the results. Here, we report the next generation HTS-PTT using ...

2010-10-04

456

cDNA sequence analysis of a 29-kDa cysteine-rich surface antigen of pathogenic Entamoeba histolytica  

Energy Technology Data Exchange (ETDEWEB)

A {lambda}gt11 cDNA library was constructed from poly(U)-Spharose-selected Entamoeba histolytica trophozoite RNA in order to clone and identify surface antigens. The library was screened with rabbit polyclonal anti-E. histolytica serum. A 700-base-pair cDNA insert was isolated and the nucleotide sequence was determined. The deduced amino acid sequence of the cDNA revealed a cysteine-rich protein. DNA hybridizations showed that the gene was specific to E. histolytica since the cDNA probe reacted with DNA from four axenic strains of E. histolytica but did not react with DNA from Entamoeba invadens, Acanthamoeba castellanii, or Trichomonas vaginalis. The insert was subcloned into the expression vector pGEX-1 and the protein was expressed as a fusion with the C terminus of glutathione S-transferase. Purified fusion protein was used to generate 22 monoclonal antibodies (mAbs) and a mouse polyclonal antiserum specific for the E. histolytica portion of the fusion protein. ...

1990-08-01

457

cDNA sequence analysis of a 29-kDa cysteine-rich surface antigen of pathogenic Entamoeba histolytica  

International Nuclear Information System (INIS)

A #lambda#gt11 cDNA library was constructed from poly(U)-Spharose-selected Entamoeba histolytica trophozoite RNA in order to clone and identify surface antigens. The library was screened with rabbit polyclonal anti-E. histolytica serum. A 700-base-pair cDNA insert was isolated and the nucleotide sequence was determined. The deduced amino acid sequence of the cDNA revealed a cysteine-rich protein. DNA hybridizations showed that the gene was specific to E. histolytica since the cDNA probe reacted with DNA from four axenic strains of E. histolytica but did not react with DNA from Entamoeba invadens, Acanthamoeba castellanii, or Trichomonas vaginalis. The insert was subcloned into the expression vector pGEX-1 and the protein was expressed as a fusion with the C terminus of glutathione S-transferase. Purified fusion protein was used to generate 22 monoclonal antibodies (mAbs) and a mouse polyclonal antiserum specific for the E. histolytica portion of the fusion protein. ...

458

Zonal differences in DNA synthesis activity and cytochrome P450 gene expression in livers of male F344 rats treated with five nongenotoxic carcinogens  

Energy Technology Data Exchange (ETDEWEB)

Both increased cell proliferation and {open_quotes}altered{close_quotes}CYP gene expression are prominent phenomena associated with liver tumor promotion by nongenotoxic carcinogen treatment. BRDU-labeled parenchymal nuclei were observed primarily in the periportal area of groups of rats, independent of nongenotoxic carcinogen treatment. Treatment with each of the 5 nongenotoxic carcinogens resulted in profound alterations in CPY gene expression at both the transcriptional and translational levels. Expression of CYP1A1, 1A1/2, 3A1, 2B1/2, and 4A immunoproteins demonstrated nongenotoxic carcinogen-specific patterns in both magnitude and zonal distribution. In agreement with the CYP immunoprotein data, treatment with each of the five nongenotoxic carcinogens resulted in a unique composition of mRNAs of CYP2B1, 2B2, 2C6, 2C11, 3A1, 3A2, and 4A1, which were variably increased or decreased relative to the untreated control livers, depending on the treatment. Similarly, the rate and pattern ...

1995-12-31

459

Transcriptional regulation in Drosophila: the post-genome challenge.  

Science.gov (United States)

Drosophila melanogaster has long been at the forefront of studies of transcriptional regulation in animals. Many fundamental ideas--such as cis control elements that act over long distances, the regulation of development by hierarchical cascades of transcription factors, dosage compensation, and position effect variegation--originated from studies of the fruit fly. The recent completion of the euchromatic DNA sequence of Drosophila is another breakthrough. The sequence data highlight important unanswered questions. For example, only one-fifth of the 124 Mb of Drosophila euchromatic DNA codes for protein. The function of the remaining 100 Mb of mostly unique DNA is largely unknown. Some proportion of this non-reading frame DNA must encode the functional recognition sites targeted by the approximately 700 sequence-specific DNA binding proteins that regulate transcription in Drosophila, but what proportion? Most or very little? Promoter sequences by definition contain all of the cis ...

2001-03-01

460

Short-term inhibition of ADP-induced platelet aggregation by clopidogrel ameliorates radiation-induced toxicity in rat small intestine.  

Science.gov (United States)

Endothelial dysfunction and increased platelet aggregation may be involved in the pathogenesis of normal tissue radiation toxicity. This study assessed clopidogrel, an inhibitor of ADP-induced platelet aggregation, as a modulator of intestinal radiation injury (radiation enteropathy). Rat small intestine was exposed to 21 Gy X-radiation. Clopidogrel (20 mg/kg/day) or vehicle was administered from 2 days before to 10 days after irradiation. Structural radiation injury, neutrophil infiltration, smooth muscle cell proliferation, collagen content, and TGF-beta1 expression were assessed 2 weeks (early phase) and 26 weeks (delayed phase) after irradiation, using quantitative histology and immunohistochemistry, morphometry, and real-time fluorogenic probe RT-PCR. Irradiated intestine exhibited significant histopathologic injury, reduced mucosal surface area, vascular sclerosis, intestinal wall fibrosis, increased collagen content, and increased TGF-beta1 expression. Clopidogrel reduced ...

2002-01-01

461

Search for the active components and studies on the mechanism of the hematopoiesis improvement foods  

Energy Technology Data Exchange (ETDEWEB)

In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herval mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Stimulation of macrophage cell line with herval extracts with the treatments of recombinant interferon-{gamma} resulted in increased nitric oxide synthesis in a dose-dependent manners. In addition, these extracts induced ...

1999-04-01

462

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

Science.gov (United States)

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 ...

2011-04-05

463

Novel snake venom ligand dendroaspis natriuretic peptide is selective for natriuretic peptide receptor-A in human heart: downregulation of natriuretic peptide receptor-A in heart failure.  

Science.gov (United States)

The natriuretic peptides are considered to be cardioprotective; however, their receptors have not been identified in human myocardium using radiolabeled analogs. Dendroaspis natriuretic peptide (DNP) has been recently identified as a new member of this peptide family and is thought to be less susceptible to enzymatic degradation. Therefore, we have developed the novel radiolabeled analog [125I]-DNP and used this to localize high-affinity (K(D)=0.2 nmol/L), saturable, specific binding sites in adult human heart (n=6) and coronary artery (n=8). In competition binding experiments, atrial natriuretic peptide and brain type natriuretic peptide had greater affinity for [125I]-DNP binding sites than C-type natriuretic peptide and the natriuretic peptide receptor (NPR)-C ligand, cANF. This rank order of potency suggested binding of [125I]-DNP was specific to NPR-A. Messenger RNA encoding NPR-A was identified in left ventricle and coronary artery smooth muscle, and ...

2006-06-15

464

Molecular cloning, genomic organization, and expression of a testicular isoform of hormone-sensitive lipase  

Energy Technology Data Exchange (ETDEWEB)

By catalyzing the rate-limiting step in adipose tissue lipolysis, hormone-sensitive lipase (HSL) is an important regulator of energy homeostasis. The role and importance of HSL in tissues other than adipose are poorly understood. We report here the cloning and expression of a testicular isoform, designated HSL{sub tes}. Due to an addition of amino acids at the NH{sub 2}-termini, rat and human HSL{sub tes} consist of 1068 and 1076 amino acids, respectively, compared to the 768 and 775 amino acids, respectively, of the adipocyte isoform (HSL{sub adi}). A novel exon of 1.2 kb, encoding the human testis-specific amino acids, was isolated and mapped to the HSL gene, 16 kb upstream of the exons encoding HSL{sub adi}. The transcribed mRNA of 3.9 kb was specifically expressed in testis. No significant similarity with other known proteins was found for the testis-specific sequence. The amino acid composition differs from the HSL{sub adi} sequence, with a notable hydrophilic ...

1996-08-01

465

Microbial community analysis of ambient temperature anaerobic digesters  

Energy Technology Data Exchange (ETDEWEB)

This paper reported on a study in which designs for Chinese and Indian fixed-dome anaerobic digesters were modified in an effort to produce smaller and more affordable digesters. While these types of systems are common in tropical regions of developing countries, they have not been used in colder climates because of the low biogas yield during the winter months. Although there is evidence that sufficient biogas production can be maintained in colder temperatures through design and operational changes, there is a lack of knowledge about the seasonal changes in the composition of the microbial communities in ambient temperature digesters. More knowledge is needed to design and operate systems for maximum biogas yield in temperate climates. The purpose of this study was to cultivate a microbial community that maximizes biogas production at psychrophilic temperatures. The study was conducted on a 300 gallon experimental anaerobic digester on the campus of Ohio State University. ...

2010-07-01

466

IGF 2 expression in 3T3 adipocytes in response to serum from hypophysectomized or diabetic swine  

Energy Technology Data Exchange (ETDEWEB)

Expression of IGF-2 and changes in its expression in response to systemic endocrine alterations have not been demonstrated for adipocytes. Adipocytes were induced to develop within cultures of 3T3-L1 cells using a medium containing 0.5mM isobutylmethylxanthine, 1uM insulin and 100ng hydrocortisone/ml for 48 hours of exposure. Cultures containing developing adipocytes were incubated with 10% pig serum and 1 uM insulin for several days. The resultant adipocyte cultures were then treated with either 10% pig serum, diabetic pig serum or hypophysectomized pig serum in DMEM for 48 hours. Adipocytes within the cultures were separated from undifferentiated cells using percoll density gradient centrifugation. Total RNA was isolated from adipocytes and dot blotted. Blots were probed with a {sup 32}P-cDNA probe for rat IGF-2. IGF-2 was expressed by the adipocytes and the pattern of expression showed specific differences between serum treatments; IGF-2 expression was highest ...

1990-02-26

467

Histopathological and immunohistochemical findings of 20 autopsy cases with 2009 H1N1 virus infection.  

Science.gov (United States)

Twenty autopsy cases with 2009 pandemic influenza A (2009 H1N1) virus infection, performed between August 2009 and February 2010, were histopathologically analyzed. Hematoxylin-eosin staining, immunohistochemistry for type A influenza nucleoprotein antigen, and real-time reverse transcription-PCR assay for viral RNA were performed on formalin-fixed and paraffin-embedded specimens. In addition, the D222G amino acid substitution in influenza virus hemagglutinin, which binds to specific cell receptors, was analyzed in formalin-fixed and paraffin-embedded trachea and lung sections by direct sequencing of PCR-amplified products. There were several histopathological patterns in the lung according to the most remarkable findings in each case: acute diffuse alveolar damage (DAD) with a hyaline membrane (four cases), organized DAD (one case), acute massive intra-alveolar edema with variable degrees of hemorrhage (three cases), neutrophilic bronchopneumonia (five cases) and ...

2011-08-26

468

Genomic analysis of the symbiotic marine crenarchaeon, Cenarchaeumsymbiosum  

Energy Technology Data Exchange (ETDEWEB)

Crenarchaea are ubiquitous and abundant microbial constituents of soils, sediments, lakes and ocean waters, yet relatively little is known about their fundamental evolutionary, ecological, and physiological properties. To better describe the ubiquitous nonthermophilic Crenarchaea, we analyzed the genome sequence of one representative, the uncultivated sponge symbiont, Cenarchaeum symbiosum. C. symbiosum genotypes coinhabiting the same host partitioned into two dominant populations, corresponding to previously described a- and b-type ribosomal RNA variants. Although synthetic, overlapping a- and b-type ribotypes harbored significant genetic variability. A single tiling path comprising the dominant a-type genotype was assembled, and used to explore the biological properties of C. symbiosum and its planktonic relatives. Out of a total of 2,066 predicted open reading frames, 36% were more highly conserved with other Archaea. The remainder partitioned between bacteria ...

2006-06-24

469

Evaluation of the Performance of the Automated NucliSENS easyMAG and EasyQ Systems versus the Roche AmpliPrep-AMPLICOR Combination for High-Throughput Monitoring of Human Immunodeficiency Virus Load?  

Science.gov (United States)

This study presents the data of an evaluation of the automated Nuclisens easyMAG and EasyQ systems versus the Roche AmpliPrep-AMPLICOR combination for testing of high-volume human immunodeficiency virus (HIV) load. This represents a follow-up of a previous study investigating the performance of the real-time Nuclisens assay using the semiautomated NucliSENS miniMAG extraction procedure. Three hundred eighteen patient samples were analyzed using both methods. The easyMAG-EasyQ HIV type 1 system has a higher sensitivity and broader dynamic range than the Cobas AmpliPrep-AMPLICOR system when the standard Roche assay is used alone, 25 to 3,000,000 IU/ml versus 400 to 750,000 HIV RNA copies/ml, respectively. There was significant correlation between the assays (0.93; P < 0.0001), with good accuracy (percent similarity mean ? = 96%), good precision (percent similarity standard deviation = 4.97%), and overall good agreement with a low percent similarity coefficient of ...

2007-05-01

470

Evaluation of NucliSens easyMAG for automated nucleic acid extraction from various clinical specimens.  

Science.gov (United States)

The objectives of this study were to evaluate the performance of the NucliSens easyMAG platform for nucleic acid extraction from different clinical specimens compared to NucliSens miniMAG platform and manual QIAGEN extraction. The NucliSens easyMAG and the NucliSens miniMAG showed equal performance on 215 throat swabs since real-time nucleic acid sequence-based amplification scored the same samples positive for Mycoplasma pneumoniae (n=9) and Chlamydia pneumoniae (n=5) RNAs, although internal control RNA was slightly better detected with the NucliSens easyMAG (99.3% versus 96.8%). NucliSens easyMAG extracted nucleic acids more efficiently (higher recovery and/or fewer inhibitors) compared to QIAGEN extraction by showing, on average, lower Ct values in real-time LightCycler PCR, although 4 individual specimen out of 45 were found positive only with QIAGEN. For nine M. pneumoniae-positive throat swabs, the mean difference in Ct values between NucliSens easyMAG ...

2006-12-13

471

Effect of endurance training on glucose transport capacity and glucose transporter expression in rat skeletal muscle  

Energy Technology Data Exchange (ETDEWEB)

The effect of 10 wk endurance swim training on 3-O-methylglucose (3-MG) uptake (at 40 mM 3-MG) in skeletal muscle was studied in the perfused rat hindquarter. Training resulted in an increase of approximately 33% for maximum insulin-stimulated 3-MG transport in fast-twitch red fibers and an increase of approximately 33% for contraction-stimulated transport in slow-twitch red fibers compared with nonexercised sedentary muscle. A fully additive effect of insulin and contractions was observed both in trained and untrained muscle. Compared with transport in control rats subjected to an almost exhaustive single exercise session the day before experiment both maximum insulin- and contraction-stimulated transport rates were increased in all muscle types in trained rats. Accordingly, the increased glucose transport capacity in trained muscle was not due to a residual effect of the last training session. Half-times for reversal of contraction-induced glucose transport were similar in trained ...

1990-12-01

472

Ectopic expression of a COOH-terminal fragment of the human telomerase reverse transcriptase leads to telomere dysfunction and reduction of growth and tumorigenicity in HeLa cells.  

Science.gov (United States)

The COOH-terminus of telomerase reverse transcriptase (hTERT) has been shown to participatein the nuclear translocation of TERT. Here, we constructed plasmids expressing the COOH-terminal M(r) 27,000 polypeptide of hTERT (hTERTC27) withthe telomerase RNA-binding domains and the reverse transcriptase domains deleted. We showed that ectopic overexpression of this polypeptide caused a defect in telomere maintenance in hTERT-positive HeLa cells, which led to senescence-like growth arrest and apoptosis. The hTERTC27 appears to work by inducing telomere dysfunction, exemplified by significantly increased anaphase chromosome end-to-end fusion events in transfected cells. Significantly, it had no effect on the cellular telomerase enzymatic activity or telomere length. The in vivo effect was further demonstrated as HeLa cells stably expressing hTERTC27 have significantly lower growth rate and reduced tumorigenicity in nude mice xenografts. Results from this study revealed ...

2002-06-01

473

Development of functional foods for radiation workers - Search for the active components and studies on the mechanism of the hematopoiesis improvement foods  

Energy Technology Data Exchange (ETDEWEB)

In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herbal mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts (Him-I, Him-II) which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Some fractions of Him-I and Him-II increased the proliferation of bone marrow cells irradiated {gamma}-ray(4Gray). Stimulation of macrophage cell line with herval extracts with the treatments of recombinant ...

2000-04-01

474

Coordinated responses of phytochelatin synthase and metallothionein genes in black mangrove, Avicennia germinans, exposed to cadmium and copper  

Energy Technology Data Exchange (ETDEWEB)

To evaluate the role of phytochelatins and metallothioneins in heavy metal tolerance of black mangrove Avicennia germinans, 3-month-old seedlings were exposed to cadmium or copper for 30 h, under hydroponic conditions. Degenerate Mt2 and PCS primers were synthesized based on amino acid and nucleotide alignment sequences reported for Mt2 and PCS in other plant species found in GenBank. Total RNA was isolated from A. germinans leaves and two partial fragments of metallothionein and phytochelatin synthase genes were isolated. Gene expression was evaluated with reverse transcripatase-polymerase chain reaction (RT-PCR) amplification technique. Temporal analysis showed that low Cd{sup 2+} and Cu{sup 2+} concentrations caused a slight (but not significant) increase in AvMt2 expression after a 16 h exposure time, while AvPCS expression showed a significant increase under the same conditions but only after 4 h. Results strongly suggest that the rapid increase in AvPCS ...

2007-08-01

475

Coordinated responses of phytochelatin synthase and metallothionein genes in black mangrove, Avicennia germinans, exposed to cadmium and copper  

International Nuclear Information System (INIS)

To evaluate the role of phytochelatins and metallothioneins in heavy metal tolerance of black mangrove Avicennia germinans, 3-month-old seedlings were exposed to cadmium or copper for 30 h, under hydroponic conditions. Degenerate Mt2 and PCS primers were synthesized based on amino acid and nucleotide alignment sequences reported for Mt2 and PCS in other plant species found in GenBank. Total RNA was isolated from A. germinans leaves and two partial fragments of metallothionein and phytochelatin synthase genes were isolated. Gene expression was evaluated with reverse transcripatase-polymerase chain reaction (RT-PCR) amplification technique. Temporal analysis showed that low Cd"2"+ and Cu"2"+ concentrations caused a slight (but not significant) increase in AvMt2 expression after a 16 h exposure time, while AvPCS expression showed a significant increase under the same conditions but only after 4 h. Results strongly suggest that the rapid increase in AvPCS expression ...

2007-08-01

476

Cloning of the cDNA for the human. beta. /sub 1/-adrenergic receptor  

Energy Technology Data Exchange (ETDEWEB)

Screening of a human placenta lambdagt11 library has led to the isolation of the cDNA for the human ..beta../sub 1/-adrenergic receptor (..beta../sub 1/AR). Used as the probe was the human genomic clone termed G-21. This clone, which contains an intronless gene for a putative receptor, was previously isolated by virtue of its cross hybridization with the human ..beta../sub 2/-adrenergic receptor (..beta../sub 2/AR). The 2.4-kilobase cDNA for the human ..beta../sub 1/AR encodes a protein of 477 amino acid residues that is 69% homologous with the avian ..beta..AR but only 54% homologous with the human ..beta../sub 2/AR. This suggests that the avian gene encoding ..beta..AR and the human gene encoding ..beta../sub 1/AR evolved from a common ancestral gene. RNA blot analysis indicates a message of 2.5 kilobases in rat tissues, with a pattern of tissue distribution consistent with ..beta../sub 1/AR binding. This pattern is quite distinct from the pattern obtained when ...

1987-11-01

477

Cloning of human basic A1, a distinct 59-kDa dystrophin-associated protein encoded on chromosome 8q23-24  

Energy Technology Data Exchange (ETDEWEB)

Duchenne and Becker muscular dystrophies are caused by defects of dystrophin, which forms a part of the membrane cytoskeleton of specialized cells such as muscle. It has been previously shown that the dystrophin-associated protein A1 (59-kDa DAP) is actually a heterogeneous group of phosphorylated proteins consisting of an acidic ({alpha}-A1) and a distinct basic ({beta}-A1) component. Partial peptide sequence of the A1 complex purified from rabbit muscle permitted the design of oligonucleotide probes that were used to isolate a cDNA for one human isoform of A1. This cDNA encodes a basic A1 isoform that is distinct from the recently described syntrophins in Torpedo and mouse and is expressed in many tissues with at least five distinct mRNA species of 5.9, 4.8, 4.3, 3.1, and 1.5 kb. A comparison of the human cDNA sequence with the GenBank expressed sequence tag (EST) data base has identified a relative from human skeletal muscle, EST25263, which is probably a human ...

1994-05-10

478

Cloning of Drosophila transcription factor Adf-1 reveals homology to Myb oncoproteins.  

Science.gov (United States)

The Drosophila sequence-specific DNA binding protein, Adf-1, is capable of activating transcription of the alcohol dehydrogenase gene, Adh, and is implicated in the transcriptional control of other developmentally regulated genes. We have cloned the cDNA encoding Adf-1 by generating specific DNA probes deduced from partial amino acid sequence of the protein. Several cDNA clones encoding an extended open reading frame were isolated from a phage lambda library. The complete amino acid sequence of Adf-1 deduced from the longest cDNA reveals structural similarities to the putative helix-turn-helix DNA binding motif of Myb and Myb-related proteins. DNA sequence analysis of genomic clones and Northern blot analysis of mRNA suggest that Adf-1 is a single-copy gene encoding a 1.9-kb transcript. Purified recombinant Adf-1 expressed in Escherichia coli binds specifically to Adf-1 recognition sites and activates transcription of a synthetic Adh promoter in vitro in a manner ...

1992-01-15

479

Caldicellulosiruptor obsidiansis sp. nov., an anaerobic, extremely thermophilic, cellulolytic bacterium isolated from Obsidian Pool, Yellowstone National Park  

Energy Technology Data Exchange (ETDEWEB)

A novel, obligately anaerobic, extremely thermophilic, cellulolytic bacterium, designated OB47T, was isolated from Obsidian Pool, Yellowstone National Park, WY, USA. The isolate was a non-motile, non-spore forming, Gram-positive rod approximately 2 m long by 0.2 m wide and grew at temperatures between 55-85oC with the optimum at 78oC. The pH range for growth was 6.0-8.0 with values of near 7.0 being optimal. Growth on cellobiose produced the fastest specific growth rates at 0.75 hr-1. The organism also displayed fermentative growth on glucose, maltose, arabinose, fructose, starch, lactose, mannose, sucrose, galactose, xylose, arabinogalactan, Avicel, xylan, filter paper, processed cardboard, pectin, dilute acid-pretreated switchgrass and Populus. OB47T was unable to grow on mannitol, fucose, lignin, Gelrite, acetate, glycerol, ribose, sorbital, carboxymethylcellulose and casein. Yeast extract stimulated growth and thiosulfate, sulfate, nitrate, and sulfur were not reduced. Fermentation ...

2010-02-01

480

Articular chondrocyte metabolism and osteoarthritis  

Energy Technology Data Exchange (ETDEWEB)

The three main objectives of this study were: (1) to determine if depletion of proteoglycans from the cartilage matrix that occurs during osteoarthritis causes a measurable increase of cartilage proteoglycan components in the synovial fluid and sera, (2) to observe what effect intracellular cAMP has on the expression of matrix components by chondrocytes, and (3) to determine if freshly isolated chondrocytes contain detectable levels of mRNA for fibronectin. Canine serum keratan sulfate and hyaluronate were measured to determine if there was an elevation of these serum glycosaminoglycans in a canine model of osteoarthritis. A single intra-articular injection of chymopapain into a shoulder joint increased serum keratan sulfate 10 fold and hyaluronate less than 2 fold in 24 hours. Keratan sulfate concentrations in synovial fluids of dogs about one year old were unrelated to the presence of spontaneous cartilage degeneration in the joints. High keratan sulfate in ...

1989-01-01

481

An Arabidopsis thaliana methyltransferase Capable of Methylating Farnesoic Acid  

Energy Technology Data Exchange (ETDEWEB)

We previously reported the identification of a new family of plant methyltransferases (MTs), named the SABATH family, that use S-adenosyl-l-methionine (SAM) to methylate a carboxyl moiety or a nitrogen-containing functional group on a diverse array of plant compounds. The Arabidopsis genome alone contains 24 distinct SABATH genes. To identify the catalytic specificities of members of this protein family in Arabidopsis, we screened recombinantly expressed and purified enzymes with a large number of potential substrates. Here, we report that the Arabidopsis thaliana gene At3g44860 encodes a protein with high catalytic specificity towards farnesoic acid (FA). Under steady-state conditions, this farnesoic acid carboxyl methyltransferase (FAMT) exhibits K{sub M} values of 41 and 71 {mu}M for FA and SAM, respectively. A three-dimensional model of FAMT constructed based upon similarity to the experimentally determined structure of Clarkia breweri salicylic acid methyltransferase (SAMT) ...

2006-01-01

482

A human breast cell model of pre-invasive to invasive transition  

Energy Technology Data Exchange (ETDEWEB)

A crucial step in human breast cancer progression is the acquisition of invasiveness. There is a distinct lack of human cell culture models to study the transition from pre-invasive to invasive phenotype as it may occur 'spontaneously' in vivo. To delineate molecular alterations important for this transition, we isolated human breast epithelial cell lines that showed partial loss of tissue polarity in three-dimensional reconstituted-basement membrane cultures. These cells remained non-invasive; however, unlike their non-malignant counterparts, they exhibited a high propensity to acquire invasiveness through basement membrane in culture. The genomic aberrations and gene expression profiles of the cells in this model showed a high degree of similarity to primary breast tumor profiles. The xenograft tumors formed by the cell lines in three different microenvironments in nude mice displayed metaplastic phenotypes, including squamous and basal characteristics, with ...

2008-03-10

483

The use of molecular biology techniques for the diagnosis and epidemiological study of foot-and-mouth disease virus in Thailand  

International Nuclear Information System (INIS)

The detection of foot-and-mouth disease (FMD) virus from various kinds of field samples (tissue extract and cell culture isolate) was studied using the polymerase chain reaction (PCR) technique. The gene selected for diagnosis was the polymerase gene and an amplification target product of 454 bp in length was produced using AP5/AP6 primer sets. The PCR product was further examined by NcoI endonuclease digestion. The presence of the internal restriction site was confirmed by demonstration of two small fragments of 330 bp and 124 bp in length. Forty-nine samples that gave positive and negative results by ELISA typing and were positive by the PCR test were tested by NcoI digestion to confirm the results. About 10% of PCR products could not be confirmed by the method. Furthermore the FMD RNA polymerase gene could be detected by the PCR method in samples negative in both ELISA typing and the virus isolation test. A total of 23 samples were examined and compared after ...

2000-05-01

484

On the impact of low power density microwaves in some living tissues  

Energy Technology Data Exchange (ETDEWEB)

The biomedical and ecological interest for the microwave impact on the Earth biosphere is continuously increased since the industrial, military and communication activities strongly contribute to the electromagnetic stress of living bodies. In the next the authors present some of the main results obtained regarding the microwave exposure of various types of biological material: bacteria, fungi, young plant seedlings, dry seeds, animal tissues. The electromagnetic exposure was carried out in open space in well controlled environmental conditions by using 10.75 GHz/1 m W cm{sup -2} microwaves. Biochemical assays and cytogenetic tests have been carried out to reveal the changes induced post irradiation. The response of some pathogen bacteria, have been emphasized by means of turbidimetric measurements - the stimulatory effect being noticed at the level of the microbial population density (the stimulation of the human body microbial flora seems to be one of the side effects of microwave ...

2006-07-01

485

Local chromatin structure of heterochromatin regulates repeatedDNA stability, nucleolus structure, and genome integrity  

Energy Technology Data Exchange (ETDEWEB)

Heterochromatin constitutes a significant portion of the genome in higher eukaryotes; approximately 30% in Drosophila and human. Heterochromatin contains a high repeat DNA content and a low density of protein-encoding genes. In contrast, euchromatin is composed mostly of unique sequences and contains the majority of single-copy genes. Genetic and cytological studies demonstrated that heterochromatin exhibits regulatory roles in chromosome organization, centromere function and telomere protection. As an epigenetically regulated structure, heterochromatin formation is not defined by any DNA sequence consensus. Heterochromatin is characterized by its association with nucleosomes containing methylated-lysine 9 of histone H3 (H3K9me), heterochromatin protein 1 (HP1) that binds H3K9me, and Su(var)3-9, which methylates H3K9 and binds HP1. Heterochromatin formation and functions are influenced by HP1, Su(var)3-9, and the RNA interference (RNAi) pathway. My thesis project ...

2007-05-05

486

Disruption of contact inhibition in rat liver epithelial cells by various types of AhR ligands  

Energy Technology Data Exchange (ETDEWEB)

The maintenance of a balance between cell gain and cell loss is essential for proper liver function. The exact role of aryl hydrocarbon receptor (AhR) in regulating cell proliferation and apoptosis of liver cells remains unclear, since ligand-dependent activation of AhR has been shown to induce cell cycle arrest, proliferation, differentiation or apoptosis, depending on the cellular model used. AhR can directly interact with retinoblastoma protein in hepatic cells, forming protein complexes that can efficiently block cell cycle progression by inducing G1 arrest, or to induce the expression of inhibitors of cyclin-dependent kinases, such as p271. On the other hand, it has been suggested that AhR could play a stimulatory role in cell proliferation, either directly or by mediating a release from contact inhibition. It is now generally accepted that progenitor cells exist in the liver, are activated in various liver diseases and can form a potential target cell population for both tumor ...

2004-09-15

487

Cellular Sources of Transforming Growth Factor-? Isoforms in Early and Chronic Radiation Enteropathy  

Science.gov (United States)

The three mammalian transforming growth factor (TGF)-? isoforms (TGF-?1, TGF-?2, and TGF-?3) differ in their putative roles in radiation-induced fibrosis in intestine and other organs. Furthermore, tissue specificity of TGF-? action may result from temporal or spatial changes in production and/or activation. The present study examined shifts in the cell types expressing TGF-? mRNA relative to TGF-? immunoreactivity and histopathological injury during radiation enteropathy development. A 4-cm loop of rat small intestine was locally exposed to 0, 12, or 21-Gy single doses of x-irradiation. Sham-irradiated and irradiated intestine were procured 2 and 26 weeks after irradiation. Cells expressing the TGF-?1, TGF-?2, or TGF-?3 transcripts were identified by in situ hybridization with digoxigenin-labeled riboprobes. Intestinal wall TGF-? immunoreactivity was measured using computerized image analysis, and structural radiation injury was assessed by quantitative ...

1998-11-01

488

Biogeochemistry of the compost bioreactor components of a composite acid mine drainage passive remediation system  

International Nuclear Information System (INIS)

The compost bioreactor ('anaerobic cell') components of three composite passive remediation systems constructed to treat acid mine drainage (AMD) at the former Wheal Jane tin mine, Cornwall, UK were studied over a period of 16 months. While there was some amelioration of the preprocessed AMD in each of the three compost bioreactors, as evidenced by pH increase and decrease in metal concentrations, only one of the cells showed effective removal of the two dominant heavy metals (iron and zinc) present. With two of the compost bioreactors, concentrations of soluble (ferrous) iron draining the cells were significantly greater than those entering the reactors, indicating that there was net mobilisation (by reductive dissolution) of colloidal and/or solid-phase ferric iron compounds within the cells. Soluble sulfide was also detected in waters draining all three compost bioreactors which was rapidly oxidised, in contrast to ferrous iron. Oxidation and hydrolysis of iron, together with ...

2005-02-01