Dramatically improved RNA in situ hybridization signals using LNA-modified probes

DEFF Research Database (Denmark)

Thomsen, Rune; Nielsen, Peter Stein; Jensen, Torben Heick

2005-01-01

. This increases the thermal stability of hybrids formed with RNA. The LNA-based probes detect specific RNAs in fixed yeast cells with an efficiency far better than conventional DNA oligonucleotide probes of the same sequence. Using this probe design, we were also able to detect poly(A)+ RNA accumulation within......In situ detection of RNA by hybridization with complementary probes is a powerful technique. Probe design is a critical parameter in successful target detection. We have evaluated the efficiency of fluorescent DNA oligonucleotides modified to contain locked nucleic acid (LNA) residues...

Synthesis and Characterization of Oligodeoxyribonucleotides Modified with 2'-Amino-α-l-LNA Adenine Monomers

DEFF Research Database (Denmark)

Andersen, Nicolai K; Anderson, Brooke A; Wengel, Jesper

2013-01-01

The development of conformationally restricted nucleotide building blocks continues to attract considerable interest because of their successful use within antisense, antigene, and other gene-targeting strategies. Locked nucleic acid (LNA) and its diastereomer α-l-LNA are two interesting examples...... (ONs) modified with 2'-amino-α-l-LNA adenine monomers W-Z. The synthesis of the target phosphoramidites 1-4 is initiated from pentafuranose 5, which upon Vorbrüggen glycosylation, O2'-deacylation, O2'-activation and C2'-azide introduction yields nucleoside 8. A one-pot tandem Staudinger....... ONs modified with pyrene-functionalized 2'-amino-α-l-LNA adenine monomers X-Z display greatly increased affinity toward DNA targets (ΔTm/modification up to +14 °C). Results from absorption and fluorescence spectroscopy suggest that the duplex stabilization is a result of pyrene intercalation...

Synthesis and Biophysical Investigations of Oligonucleotides Containing Galactose-Modified DNA, LNA and 2'-Amino-LNA Monomers

DEFF Research Database (Denmark)

Ries, Annika; Kumar, Rajesh; Lou, Chenguang

2016-01-01

Galactose-modified thymidine, LNA-T and 2'-amino-LNA-T nucleosides were synthesized, converted into the corresponding phosphoramidite derivatives and introduced into short oligonucleotides. Compared to the unmodified control strands, the galactose-modified oligonucleotides in general, and the N2'...

The effect of linoleic acid on the whole body synthesis rates of polyunsaturated fatty acids from α-linolenic acid and linoleic acid in free-living rats.

Science.gov (United States)

Domenichiello, Anthony F; Kitson, Alex P; Chen, Chuck T; Trépanier, Marc-Olivier; Stavro, P Mark; Bazinet, Richard P

2016-04-01

Docosahexaenoic acid (DHA) is thought to be important for brain function. The main dietary source of DHA is fish, however, DHA can also be synthesized from precursor omega-3 polyunsaturated fatty acids (n-3 PUFA), the most abundantly consumed being α-linolenic acid (ALA). The enzymes required to synthesize DHA from ALA are also used to synthesize longer chain omega-6 (n-6) PUFA from linoleic acid (LNA). The large increase in LNA consumption that has occurred over the last century has led to concern that LNA and other n-6 PUFA outcompete n-3 PUFA for enzymes involved in DHA synthesis, and therefore, decrease overall DHA synthesis. To assess this, rats were fed diets containing LNA at 53 (high LNA diet), 11 (medium LNA diet) or 1.5% (low LNA diet) of the fatty acids with ALA being constant across all diets (approximately 4% of the fatty acids). Rats were maintained on these diets from weaning for 8 weeks, at which point they were subjected to a steady-state infusion of labeled ALA and LNA to measure DHA and arachidonic acid (ARA) synthesis rates. DHA and ARA synthesis rates were generally highest in rats fed the medium and high LNA diets, while the plasma half-life of DHA was longer in rats fed the low LNA diet. Therefore, increasing dietary LNA, in rats, did not impair DHA synthesis; however, low dietary LNA led to a decrease in DHA synthesis with tissue concentrations of DHA possibly being maintained by a longer DHA half-life. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

LNA probe-based assay for the detection of Tomato black ring virus isolates.

Science.gov (United States)

Hasiów-Jaroszewska, Beata; Rymelska, Natalia; Borodynko, Natasza

2015-02-01

Tomato black ring virus (TBRV) infects a wide range of economically important plant species worldwide. In the present study we developed a locked nucleic acid (LNA) real-time RT-PCR assay for accurate detection of genetically diverse TBRV isolates collected from different hosts. The assay based on the LNA probe has a wide detection range, high sensitivity, stability and amplification efficiency. The assay amplified all tested TBRV isolates, but no signal was observed for the RNA from other nepoviruses and healthy plant species. Under optimum reaction conditions, the detection limit was estimated around 17 copies of the TBRV target region in total RNA. Real-time RT-PCR with the LNA probe described in this paper will serve as a valuable tool for robust, sensitive and reliable detection of TBRV isolates. Copyright © 2014 Elsevier Ltd. All rights reserved.

Crystallization and preliminary X-ray diffraction data of an LNA 7-mer duplex derived from a ricin aptamer

International Nuclear Information System (INIS)

Förster, Charlotte; Oberthuer, Dominik; Gao, Jiang; Eichert, André; Quast, Frederick G.; Betzel, Christian; Nitsche, Andreas; Erdmann, Volker A.; Fürste, Jens P.

2009-01-01

An all-LNA duplex was designed from the stem region of an RNA aptamer which has been generated against ricin. The LNA duplex was crystallized and preliminary X-ray diffraction analysis revealed diffraction to a resolution of up to 2.8 Å. Locked nucleic acids (LNAs) are modified nucleic acids which contain a modified sugar such as β-d-2′-O,4′-C methylene-bridged ribofuranose or other sugar derivatives in LNA analogues. The β-d-2′-O,4′-C methylene ribofuranose LNAs in particular possess high stability and melting temperatures, which makes them of interest for stabilizing the structure of different nucleic acids. Aptamers, which are DNAs or RNAs targeted against specific ligands, are candidates for substitution with LNAs in order to increase their stability. A 7-mer helix derived from the terminal part of an aptamer that was targeted against ricin was chosen. The ricin aptamer originally consisted of natural RNA building blocks and showed high affinity in ricin binding. For future stabilization of the aptamer, the terminal helix has been constructed as an ‘all-locked’ LNA and was successfully crystallized in order to investigate its structural properties. Optimization of crystal growth succeeded by the use of different metal salts as additives, such as CuCl 2 , MgCl 2 , MnCl 2 , CaCl 2 , CoCl 2 and ZnSO 4 . Preliminary X-ray diffraction data were collected and processed to 2.8 Å resolution. The LNA crystallized in space group P6 5 , with unit-cell parameters a = 50.11, b = 50.11, c = 40.72 Å. The crystals contained one LNA helix per asymmetric unit with a Matthews coefficient of 3.17 Å 3 Da −1 , which implies a solvent content of 70.15%

Pharmacokinetics and Pharmacodynamics of a 13-mer LNA-inhibitor-miR-221 in Mice and Non-human Primates

Directory of Open Access Journals (Sweden)

Maria Eugenia Gallo Cantafio

2016-01-01

Full Text Available Locked nucleic acid (LNA oligonucleotides have been successfully used to efficiently inhibit endogenous small noncoding RNAs in vitro and in vivo. We previously demonstrated that the direct miR-221 inhibition by the novel 13-mer LNA-i-miR-221 induces significant antimyeloma activity and upregulates canonical miR-221 targets in vitro and in vivo. To evaluate the LNA-i-miR-221 pharmacokinetics and pharmacodynamics, novel assays for oligonucleotides quantification in NOD.SCID mice and Cynomolgus monkeys (Macaca fascicularis plasma, urine and tissues were developed. To this aim, a liquid chromatography/mass spectrometry method, after solid-phase extraction, was used for the detection of LNA-i-miR-221 in plasma and urine, while a specific in situ hybridization assay for tissue uptake analysis was designed. Our analysis revealed short half-life, optimal tissue biovailability and minimal urine excretion of LNA-i-miR-221 in mice and monkeys. Up to 3 weeks, LNA-i-miR-221 was still detectable in mice vital organs and in xenografted tumors, together with p27 target upregulation. Importantly, no toxicity in the pilot monkey study was observed. Overall, our findings indicate the suitability of LNA-i-miR-221 for clinical use and we provide here pilot data for safety analysis and further development of LNA-miRNA-based therapeutics for human cancer.

A locked nucleic acid (LNA-based real-time PCR assay for the rapid detection of multiple bacterial antibiotic resistance genes directly from positive blood culture.

Directory of Open Access Journals (Sweden)

Lingxiang Zhu

Full Text Available Bacterial strains resistant to various antibiotic drugs are frequently encountered in clinical infections, and the rapid identification of drug-resistant strains is highly essential for clinical treatment. We developed a locked nucleic acid (LNA-based quantitative real-time PCR (LNA-qPCR method for the rapid detection of 13 antibiotic resistance genes and successfully used it to distinguish drug-resistant bacterial strains from positive blood culture samples. A sequence-specific primer-probe set was designed, and the specificity of the assays was assessed using 27 ATCC bacterial strains and 77 negative blood culture samples. No cross-reaction was identified among bacterial strains and in negative samples, indicating 100% specificity. The sensitivity of the assays was determined by spiking each bacterial strain into negative blood samples, and the detection limit was 1-10 colony forming units (CFU per reaction. The LNA-qPCR assays were first applied to 72 clinical bacterial isolates for the identification of known drug resistance genes, and the results were verified by the direct sequencing of PCR products. Finally, the LNA-qPCR assays were used for the detection in 47 positive blood culture samples, 19 of which (40.4% were positive for antibiotic resistance genes, showing 91.5% consistency with phenotypic susceptibility results. In conclusion, LNA-qPCR is a reliable method for the rapid detection of bacterial antibiotic resistance genes and can be used as a supplement to phenotypic susceptibility testing for the early detection of antimicrobial resistance to allow the selection of appropriate antimicrobial treatment and to prevent the spread of resistant isolates.

Inhibition of hepatitis B virus (HBV) by LNA-mediated nuclear interference with HBV DNA transcription

International Nuclear Information System (INIS)

Sun, Zhen; Xiang, Wenqing; Guo, Yajuan; Chen, Zhi; Liu, Wei; Lu, Daru

2011-01-01

Highlights: → LNA-modified oligonucleotides can pass through the plasma membrane of cultured cells even without using transfection machinery. → LNA-modified oligonucleotides passed efficiently across the cell membrane, and lipid-coating facilitated translocation from the cytoplasm to the nucleus. → LNA-oligonucleotide designed to target nuclear HBV DNA efficiently suppresses HBV replication and transcription in cultured hepatic cells. -- Abstract: Silencing target genes with small regulatory RNAs is widely used to investigate gene function and therapeutic drug development. Recently, triplex-based approaches have provided another attractive means to achieve targeted gene regulation and gene manipulation at the molecular and cellular levels. Nuclear entry of oligonucleotides and enhancement of their affinity to the DNA targets are key points of such approaches. In this study, we developed lipid-based transport of a locked-nucleic-acid (LNA)-modified oligonucleotide for hepatitis B virus (HBV) DNA interference in human hepatocytes expressing HBV genomic DNA. In these cells, the LNA-modified oligonucleotides passed efficiently across the cell membrane, and lipid-coating facilitated translocation from the cytoplasm to the nucleus. The oligonucleotide specifically targeting HBV DNA clearly interfered with HBV DNA transcription as shown by a block in pregenomic RNA (pgRNA) production. The HBV DNA-targeted oligonucleotide suppressed HBV DNA replication and HBV protein production more efficiently than small interfering RNAs directed to the pgRNA. These results demonstrate that fusion with lipid can carry LNA-modified oligonucleotides to the nucleus where they regulate gene expression. Interfering with HBV DNA transcription by LNA-modified oligonucleotides has strong potential as a new strategy for HBV inhibition.

Inhibition of hepatitis B virus (HBV) by LNA-mediated nuclear interference with HBV DNA transcription

Energy Technology Data Exchange (ETDEWEB)

Sun, Zhen [The State Key Laboratory of Genetic Engineering and The MOE Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai 200433 (China); Department of Biochemistry and Molecular Biology, Program in Molecular Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058 (China); Xiang, Wenqing; Guo, Yajuan [Department of Biochemistry and Molecular Biology, Program in Molecular Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058 (China); Chen, Zhi [The State Key Laboratory for Infectious Disease, Institute of Infectious Disease, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003 (China); Liu, Wei, E-mail: liuwei666@zju.edu.cn [Department of Biochemistry and Molecular Biology, Program in Molecular Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058 (China); Lu, Daru, E-mail: drlu@fudan.edu.cn [The State Key Laboratory of Genetic Engineering and The MOE Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai 200433 (China)

2011-06-10

Highlights: {yields} LNA-modified oligonucleotides can pass through the plasma membrane of cultured cells even without using transfection machinery. {yields} LNA-modified oligonucleotides passed efficiently across the cell membrane, and lipid-coating facilitated translocation from the cytoplasm to the nucleus. {yields} LNA-oligonucleotide designed to target nuclear HBV DNA efficiently suppresses HBV replication and transcription in cultured hepatic cells. -- Abstract: Silencing target genes with small regulatory RNAs is widely used to investigate gene function and therapeutic drug development. Recently, triplex-based approaches have provided another attractive means to achieve targeted gene regulation and gene manipulation at the molecular and cellular levels. Nuclear entry of oligonucleotides and enhancement of their affinity to the DNA targets are key points of such approaches. In this study, we developed lipid-based transport of a locked-nucleic-acid (LNA)-modified oligonucleotide for hepatitis B virus (HBV) DNA interference in human hepatocytes expressing HBV genomic DNA. In these cells, the LNA-modified oligonucleotides passed efficiently across the cell membrane, and lipid-coating facilitated translocation from the cytoplasm to the nucleus. The oligonucleotide specifically targeting HBV DNA clearly interfered with HBV DNA transcription as shown by a block in pregenomic RNA (pgRNA) production. The HBV DNA-targeted oligonucleotide suppressed HBV DNA replication and HBV protein production more efficiently than small interfering RNAs directed to the pgRNA. These results demonstrate that fusion with lipid can carry LNA-modified oligonucleotides to the nucleus where they regulate gene expression. Interfering with HBV DNA transcription by LNA-modified oligonucleotides has strong potential as a new strategy for HBV inhibition.

Effect of dietary docosahexaenoic acid on biosynthesis of docosahexaenoic acid from alpha-linolenic acid in young rats

OpenAIRE

DeMar, James C.; DiMartino, Carmine; Baca, Adam W.; Lefkowitz, William; Salem, Norman

2008-01-01

Docosahexaenoic acid (DHA), a crucial nervous system n-3 PUFA, may be obtained in the diet or synthesized in vivo from dietary α-linolenic acid (LNA). We addressed whether DHA synthesis is regulated by the availability of dietary DHA in artificially reared rat pups, during p8 to p28 development. Over 20 days, one group of rat pups was continuously fed deuterium-labeled LNA (d5-LNA) and no other n-3 PUFA (d5-LNA diet), and a second group of rat pups was fed a d5-LNA diet with un...

Hybridization-Based Detection of Helicobacter pylori at Human Body Temperature Using Advanced Locked Nucleic Acid (LNA) Probes

Science.gov (United States)

Fontenete, Sílvia; Guimarães, Nuno; Leite, Marina; Figueiredo, Céu; Wengel, Jesper; Filipe Azevedo, Nuno

2013-01-01

The understanding of the human microbiome and its influence upon human life has long been a subject of study. Hence, methods that allow the direct detection and visualization of microorganisms and microbial consortia (e.g. biofilms) within the human body would be invaluable. In here, we assessed the possibility of developing a variant of fluorescence in situ hybridization (FISH), named fluorescence in vivo hybridization (FIVH), for the detection of Helicobacter pylori. Using oligonucleotide variations comprising locked nucleic acids (LNA) and 2’-O-methyl RNAs (2’OMe) with two types of backbone linkages (phosphate or phosphorothioate), we were able to successfully identify two probes that hybridize at 37 °C with high specificity and sensitivity for H. pylori, both in pure cultures and in gastric biopsies. Furthermore, the use of this type of probes implied that toxic compounds typically used in FISH were either found to be unnecessary or could be replaced by a non-toxic substitute. We show here for the first time that the use of advanced LNA probes in FIVH conditions provides an accurate, simple and fast method for H. pylori detection and location, which could be used in the future for potential in vivo applications either for this microorganism or for others. PMID:24278398

C5-Alkynyl-Functionalized ?-L-LNA: Synthesis, Thermal Denaturation Experiments and Enzymatic Stability

OpenAIRE

Kumar, Pawan; Baral, Bharat; Anderson, Brooke A.; Guenther, Dale C.; ?stergaard, Michael E.; Sharma, Pawan K.; Hrdlicka, Patrick J.

2014-01-01

Major efforts are currently being devoted to improving the binding affinity, target specificity, and enzymatic stability of oligonucleotides used for nucleic acid targeting applications in molecular biology, biotechnology, and medicinal chemistry. One of the most popular strategies toward this end has been to introduce additional modifications to the sugar ring of affinity-inducing conformationally restricted nucleotide building blocks such as locked nucleic acid (LNA). In the preceding artic...

Synthetic LNA/DNA nano-scaffolds for highly efficient diagnostics of nucleic acids and autoimmune antibodies

DEFF Research Database (Denmark)

Astakhova, Irina Kira

2014-01-01

) strands and a series of fluorescent azides. The multiply labeled fluorescent LNA/DNA probes prepared herein generally display high binding affinity to complementary DNA/RNA, high quantum yields and, hence, high fluorescence brightness values. With the novel fluorescent probes, specific sensing...

A wideband Noise-Canceling CMOS LNA exploiting a transformer

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, Domine M.W.; Nauta, Bram

2006-01-01

Abstract — A broadband LNA incorporating single-ended to differential conversion, has been successfully implemented using a noise-canceling technique and a single on-chip transformer. The LNA achieves a high voltage gain of 19dB, a wideband input match (2.5–4.0 GHz), and a Noise Figure of 4–5.4 dB,

A wideband Noise-Canceling CMOS LNA exploiting a transformer

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, Domine M.W.; Nauta, Bram

2006-01-01

A broadband LNA incorporating single-ended to differential conversion, has been successfully implemented using a noise-canceling technique and a single on-chip transformer. The LNA achieves a high voltage gain of 19dB, a wideband input match (2.5–4.0 GHz), and a Noise Figure of 4–5.4 dB, while

Scaffolding along Nucleic Acid Duplexes Using 2'-Amino-Locked Nucleic Acids

DEFF Research Database (Denmark)

Astakhova, I Kira; Wengel, Jesper

2014-01-01

-LNA nucleotides. By application of different chemical reactions, modification of 2'-amino-LNA scaffolds can be efficiently performed in high yields and with various tags, postsynthetically or during the automated oligonucleotide synthesis. The choice of a synthetic method for scaffolding along 2'-amino-LNA mainly....../DNA probes bind nucleic acid targets with advantages of high affinity and specificity. Thus, molecular motion of nanodevices and programmable self-assembly of chemically modified LNA/DNA nanomaterials can be followed by bright fluorescence signaling from the functionalized LNA units. Another appealing aspect...

Locked nucleic acid

DEFF Research Database (Denmark)

Jepsen, Jan Stenvang; Sørensen, Mads D; Wengel, Jesper

2004-01-01

Locked nucleic acid (LNA) is a class of nucleic acid analogs possessing very high affinity and excellent specificity toward complementary DNA and RNA, and LNA oligonucleotides have been applied as antisense molecules both in vitro and in vivo. In this review, we briefly describe the basic...

Threshold changes in rat brain docosahexaenoic acid incorporation and concentration following graded reductions in dietary alpha-linolenic acid

Science.gov (United States)

Taha, Ameer Y.; Chang, Lisa; Chen, Mei

2016-01-01

Background This study tested the dietary level of alpha-linolenic acid (α-LNA, 18:3n-3) sufficient to maintain brain 14C-Docosahexaenoic acid (DHA, 22:6n-3) metabolism and concentration following graded α-LNA reduction. Methods 18–21 day male Fischer-344 (CDF) rats were randomized to the AIN-93G diet containing as a % of total fatty acids, 4.6% (“n-3 adequate”), 3.6%, 2.7%, 0.9% or 0.2% (“n-3 deficient”) α-LNA for 15 weeks. Rats were intravenously infused with 14C-DHA to steady state for 5 minutes, serial blood samples collected to obtain plasma and brains excised following microwave fixation. Labeled and unlabeled DHA concentrations were measured in plasma and brain to calculate the incorporation coefficient, k*, and incorporation rate, Jin. Results Compared to 4.6% α-LNA controls, k* was significantly increased in ethanolamine glycerophospholipids in the 0.2% α-LNA group. Circulating unesterified DHA and brain incorporation rates (Jin) were significantly reduced at 0.2% α-LNA. Brain total lipid and phospholipid DHA concentrations were reduced at or below 0.9% α-LNA. Conclusion Threshold changes for brain DHA metabolism and concentration were maintained at or below 0.9% dietary α-LNA, suggesting the presence of homeostatic mechanisms to maintain brain DHA metabolism when dietary α-LNA intake is low. PMID:26869088

Photoligation of self-assembled DNA constructs containing anthracene-functionalized 2'-amino-LNA monomers

DEFF Research Database (Denmark)

Pasternak, Karol; Pasternak, Anna; Gupta, Pankaj

2011-01-01

Efficient synthesis of a novel anthracene-functionalized 2'-amino-LNA phosphoramidite derivative is described together with its incorporation into oligodeoxynucleotides. Two DNA strands with the novel 2'-N-anthracenylmethyl-2'-amino-LNA monomers can be effectively cross-linked by photoligation...... at 366nm in various types of DNA constructs. Successful application of three differently functionalized 2'-amino-LNA monomers in self-assembled higher ordered structures for simultaneous cross-linking and monitoring of assembly formation is furthermore demonstrated....

A high linearity SiGe HBT LNA for GPS receiver

International Nuclear Information System (INIS)

Luo Yanbin; Shi Jian; Ma Chengyan; Gan Yebing; Qian Min

2014-01-01

A high linearity 1.575 GHz SiGe:HBT low noise amplifier (LNA) for global positioning system applications is described. The bipolar cascoded with an MOSFET LNA was fabricated in a commercial 0.18 μm SiGe BiCMOS process. A resistor bias feed circuit with a feedback resistor was designed for the LNA input transistor to improve its intermodulation and compression performance. The packaged chip tested on board has displayed a noise figure of 1.11 dB, a power gain of 18 dB, an output 1 dB compression point of +7.8 dBm and an input third-order intercept point of +1.8 dBm. The chip occupies a 500 × 560 μm 2 area and consumes 3.6 mA from a 2.85 V power supply. (semiconductor integrated circuits)

LNA-enhanced detection of single nucleotide polymorphisms in the apolipoprotein E

DEFF Research Database (Denmark)

Jacobsen, Nana; Bentzen, Joan; Meldgaard, Michael

2002-01-01

Genotyping of single nucleotide polymorphisms (SNPs) in large populations presents a great challenge, especially if the SNPs are embedded in GC-rich regions, such as the codon 112 SNP in the human apolipoprotein E (apoE). In the present study, we have used immobilized locked nucleic acid (LNA...... was applied to a panel of patient samples with simultaneous genotyping of the patients by DNA sequencing. The apoE genotyping assays for the codons 112 and 158 SNPs resulted in unambiguous results for all patient samples, concurring with those obtained by DNA sequencing....

Formation of (DNA)2-LNA triplet with recombinant base recognition: A quantum mechanical study

Science.gov (United States)

Mall, Vijaya Shri; Tiwari, Rakesh Kumar

2018-05-01

The formation of DNA triple helix offers the verity of new possibilities in molecular biology. However its applications are limited to purine and pyrimidine rich sequences recognized by forming Hoogsteen/Reverse Hoogsteen triplets in major groove sites of DNA duplex. To overcome this drawback modification in bases backbone and glucose of nucleotide unit of DNA have been proposed so that the third strand base recognized by both the bases of DNA duplex by forming Recombinant type(R-type) of bonding in mixed sequences. Here we performed Quanrum Mechanical (Hartree-Fock and DFT) methodology on natural DNA and Locked Nucleic Acids(LNA) triplets using 6-31G and some other new advance basis sets. Study suggests energetically stable conformation has been observed for recombinant triplets in order of G-C*G > A-T*A > G-C*C > T-A*T for both type of triplets. Interestingly LNA leads to more stable conformation in all set of triplets, clearly suggests an important biological tool to overcome above mentioned drawbacks.

Highly Efficient Synthesis of Allopurinol Locked Nucleic Acid Monomer by C6 Deamination of 8-Aza-7-bromo-7-deazaadenine Locked Nucleic Acid Monomer

DEFF Research Database (Denmark)

Kosbar, Tamer Reda El-Saeed; Sofan, M.; Abou-Zeid, L.

2013-01-01

An allopurinol locked nucleic acid (LNA) monomer was prepared by a novel strategy through C6 deamination of the corresponding 8-aza-7-bromo-7-deazaadenine LNA monomer with aqueous sodium hydroxide. An 8-aza-7-deazaadenine LNA monomer was also synthesized by a modification of the new synthetic...... the required LNA monomers....

Oligodeoxynucleotides containing 2'-amino-LNA nucleotides as constrained morpholino phosphoramidate and phosphorodiamidate monomers

DEFF Research Database (Denmark)

Kristensen, Kim Vejlegaard; Paul, Sibasish; Kosbar, Tamer

2017-01-01

Incorporation in a 2'→5' direction of a phosphorodiamidite 2'-amino-LNA-T nucleotide as the morpholino phosphoramidate and N,N-dimethylamino phosphorodiamidate monomers into six oligonucleotides is reported. Thermal denaturation studies showed that the novel 2'-amino-LNA-based morpholino monomers...

Application of locked nucleic acid-based probes in fluorescence in situ hybridization

DEFF Research Database (Denmark)

Fontenete, Sílvia; Carvalho, Daniel R; Guimarães, Nuno

2016-01-01

of nucleic acid mimics used as mixmers in LNA-based probes strongly influence the efficiency of detection. LNA probes with 10 to 15 mers showed the highest efficiency. Additionally, the combination of 2′-OMe RNA with LNA allowed an increase on the fluorescence intensities of the probes. Overall......Fluorescence in situ hybridization (FISH) employing nucleic acid mimics as probes is becoming an emerging molecular tool in the microbiology area for the detection and visualization of microorganisms. However, the impact that locked nucleic acid (LNA) and 2′-O-methyl (2′-OMe) RNA modifications have...

Selection of LNA-containing DNA aptamers against recombinant human CD73

DEFF Research Database (Denmark)

Elle, Ida C; Karlsen, Kasper K; Terp, Mikkel G

2015-01-01

tested by surface plasmon resonance. Truncated variants of these aptamers and variants where the LNA nucleotides were substituted for the DNA equivalent also exhibited affinity for the recombinant CD73 in the low nanomolar range. In enzyme inhibition assays with recombinant CD73 the aptamer sequences......LNA-containing DNA aptamers against CD73 (human ecto-5'-nucleotidase), a protein frequently overexpressed in solid tumours, were isolated by SELEX. A pre-defined stem-loop library, containing LNA in the forward primer region, was enriched with CD73 binding sequences through six rounds of SELEX...... with recombinant his-tagged CD73 immobilised on anti-his plates. Enriched pools isolated from rounds one, three and six were subjected to next-generation sequencing and analysed for enrichment using custom bioinformatics software. The software identified aptamer sequences via the primers and then performed several...

Synthesis, hybridization characteristics, and fluorescence properties of oligonucleotides modified with nucleobase-functionalized locked nucleic acid adenosine and cytidine monomers.

Science.gov (United States)

Kaura, Mamta; Kumar, Pawan; Hrdlicka, Patrick J

2014-07-03

Conformationally restricted nucleotides such as locked nucleic acid (LNA) are very popular as affinity-, specificity-, and stability-enhancing modifications in oligonucleotide chemistry to produce probes for nucleic acid targeting applications in molecular biology, biotechnology, and medicinal chemistry. Considerable efforts have been devoted in recent years to optimize the biophysical properties of LNA through additional modification of the sugar skeleton. We recently introduced C5-functionalization of LNA uridines as an alternative and synthetically more straightforward approach to improve the biophysical properties of LNA. In the present work, we set out to test the generality of this concept by studying the characteristics of oligonucleotides modified with four different C5-functionalized LNA cytidine and C8-functionalized LNA adenosine monomers. The results strongly suggest that C5-functionalization of LNA pyrimidines is indeed a viable approach for improving the binding affinity, target specificity, and/or enzymatic stability of LNA-modified ONs, whereas C8-functionalization of LNA adenosines is detrimental to binding affinity and specificity. These insights will impact the future design of conformationally restricted nucleotides for nucleic acid targeting applications.

A Wideband Balun LNA I/Q-Mixer combination in 65nm CMOS

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, D.M.W.; Nauta, Bram

2008-01-01

An inductor-less LNA-mixer topology merges an I/Q current-commutating mixer with a noise-canceling balun/LNA. The topology achieves >18dB conversion gain, a flat NF<5.5dB, IIP2=+20dBm and IIP3=-3dBm from 500MHz to 7GHz. The core circuit consumes 16mW and occupies less than 0.01mm2 in 65nm CMOS.

Design of 2.4Ghz CMOS Floating Active Inductor LNA using 130nm Technology

Science.gov (United States)

Muhamad, M.; Soin, N.; Ramiah, H.

2018-03-01

This paper presents about design and optimization of CMOS active inductor integrated circuit. This active inductor implements using Silterra 0.13μm technology and simulated using Cadence Virtuoso and Spectre RF. The center frequency for this active inductor is at 2.4 GHz which follow IEEE 802.11 b/g/n standard. To reduce the chip size of silicon, active inductor is used instead of passive inductor at low noise amplifier LNA circuit. This inductor test and analyse by low noise amplifier circuit. Comparison between active with passive inductor based on LNA circuit has been performed. Result shown that the active inductor has significantly reduce the chip size with 73 % area without sacrificing the noise figure and gain of LNA which is the most important criteria in LNA. The best low noise amplifier provides a power gain (S21) of 20.7 dB with noise figure (NF) of 2.1dB.

Kinetics of membrane damage to high (HNA) and low (LNA) nucleic acid bacterial clusters in drinking water by ozone, chlorine, chlorine dioxide, monochloramine, ferrate(VI), and permanganate.

Science.gov (United States)

Ramseier, Maaike K; von Gunten, Urs; Freihofer, Pietro; Hammes, Frederik

2011-01-01

Drinking water was treated with ozone, chlorine, chlorine dioxide, monochloramine, ferrate(VI), and permanganate to investigate the kinetics of membrane damage of native drinking water bacterial cells. Membrane damage was measured by flow cytometry using a combination of SYBR Green I and propidium iodide (SGI+PI) staining as indicator for cells with permeabilized membranes and SGI alone to measure total cell concentration. SGI+PI staining revealed that the cells were permeabilized upon relatively low oxidant exposures of all tested oxidants without a detectable lag phase. However, only ozonation resulted in a decrease of the total cell concentrations for the investigated reaction times. Rate constants for the membrane damage reaction varied over seven orders of magnitude in the following order: ozone > chlorine > chlorine dioxide ≈ ferrate > permanganate > chloramine. The rate constants were compared to literature data and were in general smaller than previously measured rate constants. This confirmed that membrane integrity is a conservative and therefore safe parameter for disinfection control. Interestingly, the cell membranes of high nucleic acid (HNA) content bacteria were damaged much faster than those of low nucleic acid (LNA) content bacteria during treatment with chlorine dioxide and permanganate. However, only small differences were observed during treatment with chlorine and chloramine, and no difference was observed for ferrate treatment. Based on the different reactivity of these oxidants it was suggested that HNA and LNA bacterial cell membranes have a different chemical constitution. Copyright © 2010 Elsevier Ltd. All rights reserved.

A locked nucleic Acid-based nanocrawler

DEFF Research Database (Denmark)

Astakhova, I Kira; Pasternak, Karol; Campbell, Meghan A

2013-01-01

Herein we introduce a novel fluorescent LNA/DNA machine, a nanocrawler, which reversibly moves along a directionally polar complementary road controlled by affinity-enhancing locked nucleic acid (LNA) monomers and additional regulatory strands. Polyaromatic hydrocarbon (PAH) dyes attached to 2...

Production of a conjugated fatty acid by Bifidobacterium breve LMC520 from α-linolenic acid: conjugated linolenic acid (CLnA).

Science.gov (United States)

Park, Hui Gyu; Cho, Hyung Taek; Song, Myoung-Chong; Kim, Sang Bum; Kwon, Eung Gi; Choi, Nag Jin; Kim, Young Jun

2012-03-28

This study was performed to characterize natural CLnA isomer production by Bifidobacterium breve LMC520 of human origin in comparison to conjugated linoleic acid (CLA) production. B. breve LMC520 was found to be highly active in terms of CLnA production, of which the major portion was identified as cis-9,trans-11,cis-15 CLnA isomer by GC-MS and NMR analysis. B. breve LMC520 was incubated for 48 h using MRS medium (containing 0.05% L-cysteine · HCl) under different environmental conditions such as atmosphere, pH, and substrate concentration. The high conversion rate of α-linolenic acid (α-LNA) to CLnA (99%) was retained up to 2 mM α-LNA, and the production was proportionally increased nearly 7-fold with 8 mM by the 6 h of incubation under anaerobic conditions at a wide range of pH values (between 5 and 9). When α-LNA was compared with linoleic acid (LA) as a substrate for isomerization by B. breve LMC520, the conversion of α-LNA was higher than that of LA. These results demonstrated that specific CLnA isomer could be produced through active bacterial conversion at an optimized condition. Because many conjugated octadecatrienoic acids in nature are shown to play many positive roles, the noble isomer found in this study has potential as a functional source.

Role of the heat capacity change in understanding and modeling melting thermodynamics of complementary duplexes containing standard and nucleobase-modified LNA.

Science.gov (United States)

Hughesman, Curtis B; Turner, Robin F B; Haynes, Charles A

2011-06-14

Melting thermodynamic data obtained by differential scanning calorimetry (DSC) are reported for 43 duplexed oligonucleotides containing one or more locked nucleic acid (LNA) substitutions. The measured heat capacity change (ΔC(p)) for the helix-to-coil transition is used to compute the changes in enthalpy and entropy for melting of an LNA-bearing duplex at the T(m) of its corresponding isosequential unmodified DNA duplex to allow rigorous thermodynamic analysis of the stability enhancements provided by LNA substitutions. Contrary to previous studies, our analysis shows that the origin of the improved stability is almost exclusively a net reduction (ΔΔS° thermodynamics and the increased melting temperature (ΔT(m)) of heteroduplexes formed between an unmodified DNA strand and a complementary strand containing any number and configuration of standard LNA nucleotides A, T, C, and G. This single-base thermodynamic (SBT) model requires only four entropy-related parameters in addition to ΔC(p). Finally, DSC data for 20 duplexes containing the nucleobase-modified LNAs 2-aminoadenine (D) and 2-thiothymine (H) are reported and used to determine SBT model parameters for D and H. The data and model suggest that along with the greater stability enhancement provided by D and H bases relative to their corresponding A and T analogues, the unique pseudocomplementary properties of D-H base pairs may make their use appealing for in vitro and in vivo applications.

Cleavage and protection of locked nucleic acid-modified DNA by restriction endonucleases

DEFF Research Database (Denmark)

Crouzier, Lucile; Dubois, Camille; Wengel, Jesper

2012-01-01

Locked nucleic acid (LNA) is one of the most prominent nucleic acid analogues reported so far. We herein for the first time report cleavage by restriction endonuclease of LNA-modified DNA oligonucleotides. The experiments revealed that RsaI is an efficient enzyme capable of recognizing and cleaving...

A wideband LNA employing gate-inductive-peaking and noise-canceling techniques in 0.18 μm CMOS

International Nuclear Information System (INIS)

Bao Kuan; Fan Xiangning; Li Wei; Zhang Li; Wang Zhigong

2012-01-01

This paper presents a wideband low noise amplifier (LNA) for multi-standard radio applications. The low noise characteristic is achieved by the noise-canceling technique while the bandwidth is enhanced by gate-inductive-peaking technique. High-frequency noise performance is consequently improved by the flattened gain over the entire operating frequency band. Fabricated in 0.18 μm CMOS process, the LNA achieves 2.5 GHz of −3 dB bandwidth and 16 dB of gain. The gain variation is within ±0.8 dB from 300 MHz to 2.2 GHz. The measured noise figure (NF) and average IIP3 are 3.4 dB and −2 dBm, respectively. The proposed LNA occupies 0.39 mm 2 core chip area. Operating at 1.8 V, the LNA drains a current of 11.7 mA. (semiconductor integrated circuits)

LNA-modified oligonucleotides mediate specific inhibition of microRNA function

DEFF Research Database (Denmark)

Ørom, Ulf Andersson; Kauppinen, Sakari; Lund, Anders H

2006-01-01

microRNAs are short, endogenous non-coding RNAs that act as post-transcriptional modulators of gene expression. Important functions for microRNAs have been found in the regulation of development, cellular proliferation and differentiation, while perturbed miRNA expression patterns have been...... observed in many human cancers. Here we present a method for specific inhibition of miRNA function through interaction with LNA-modified antisense oligonucleotides and report the specificity of this application. We show that LNA-modified oligonucleotides can inhibit exogenously introduced miRNAs with high...... specificity using a heterologous reporter assay, and furthermore demonstrate their ability to inhibit an endogenous miRNA in Drosophila melanogaster cells, leading to up-regulation of the cognate target protein. The method shows stoichiometric and reliable inhibition of the targeted miRNA and can thus...

Enhanced anti-HIV-1 activity of G-quadruplexes comprising locked nucleic acids and intercalating nucleic acids

DEFF Research Database (Denmark)

Pedersen, Erik Bjerregaard; Nielsen, Jakob Toudahl; Nielsen, Claus

2011-01-01

Two G-quadruplex forming sequences, 50-TGGGAG and the 17-mer sequence T30177, which exhibit anti-HIV-1 activity on cell lines, were modified using either locked nucleic acids (LNA) or via insertions of (R)-1-O-(pyren-1-ylmethyl)glycerol (intercalating nucleic acid, INA) or (R)-1-O-[4-(1......-pyrenylethynyl)phenylmethyl]glycerol (twisted intercalating nucleic acid, TINA). Incorporation of LNA or INA/TINA monomers provide as much as 8-fold improvement of anti-HIV-1 activity. We demonstrate for the first time a detailed analysis of the effect the incorporation of INA/TINA monomers in quadruplex forming...

LNA A 1.9 GHZ low noise amplifier

Directory of Open Access Journals (Sweden)

Jorge Julián Moreno-Rubio

2006-12-01

Full Text Available This paper shows the design, the simulation, and the layout from a low noise amplifier (LNA, designed with and approximate band from 25 to 80 MHz. The design results of the matching neworks are shown, its noise figure, its available and transduced gain according to its non lineal model (TOM, the DC network, crash inductors and matching capacitors with the large impedance transmission lines.

Selection of G-quadruplex folding topology with LNA-modified human telomeric sequences in K+ solution

DEFF Research Database (Denmark)

Pradhan, Devranjan; Hansen, Lykke H; Vester, Birte

2011-01-01

G-rich nucleic acid oligomers can form G-quadruplexes built by G-tetrads stacked upon each other. Depending on the nucleotide sequence, G-quadruplexes fold mainly with two topologies: parallel, in which all G-tracts are oriented parallel to each other, or antiparallel, in which one or more G......-tracts are oriented antiparallel to the other G-tracts. In the former topology, all glycosidic bond angles conform to anti conformations, while in the latter topology they adopt both syn and anti conformations. It is of interest to understand the molecular forces that govern G-quadruplex folding. Here, we approach...... this problem by examining the impact of LNA (locked nucleic acid) modifications on the folding topology of the dimeric model system of the human telomere sequence. In solution, this DNA G-quadruplex forms a mixture of G-quadruplexes with antiparallel and parallel topologies. Using CD and NMR spectroscopies, we...

Influence of the Antenna Impedance Variation and Input Matching Network Q on LNA Key Figures

DEFF Research Database (Denmark)

Ruaro, Andrea; Kvist, Søren Helstrup; Gülstorff, Steen

2012-01-01

In this paper we present an analysis of the behaviour of a 2:4 GHz Low Noise Amplifier (LNA) for Wireless Body Area Network (WBAN) applications facing antennadetuning issue. An amplifier with ultra-low power, low voltage, and with reduced component count is prototyped to validate simulation results......, then the behaviour is analyzed through simulations based on data measured on real users. The analysis shows that the designed LNA is stable to the antenna impedance variation expectable in most cases, while highlights the possible risks associated to a high-Q input matching network when used in a context prone...

The BLIXER, a Wideband Balun-LNA-I/Q-Mixer Topology

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, Domine M.W.; Nauta, Bram

2008-01-01

Abstract—This paper proposes to merge an I/Q current-commutating mixer with a noise-canceling balun-LNA. To realize a high bandwidth, the real part of the impedance of all RF nodes is kept low, and the voltage gain is not created at RF but in baseband where capacitive loading is no problem. Thus a

Rapid genotyping using pyrene-perylene locked nucleic acid complexes

DEFF Research Database (Denmark)

Kumar, Santhosh T.; Myznikova, Anna; Samokhina, Evgeniya

2013-01-01

We have developed an assay for single strand DNA and RNA detection which is based on novel pyrene-perylene FRET pairs attached to short LNA/DNA probes. The assay is based on ratiometric emission upon binding of target DNA/RNA by three combinations of fluorescent LNA/DNA reporter strands. Specific...... geometry of the pyrene fluorophore attached to the 2'-amino group of 2'-amino-LNA in position 4 allows for the first time to efficiently utilize dipole-dipole orientation parameter for sensing of single-nucleotide polymorphisms (SNPs) in nucleic acid targets by FRET. Using novel probes, SNP detection......-perylene FRET pairs, e.g., in imaging and clinical diagnostics....

Optimization of the carrot leaf dehydration aiming at the preservation of omega-3 fatty acids

Directory of Open Access Journals (Sweden)

Vanessa Vivian de Almeida

2009-01-01

Full Text Available The carrot leaf dehydration conditions in air circulation oven were optimized through response surface methodology (RSM for minimizing the degradation of polyunsaturated fatty acids, particularly alpha-linolenic (LNA, 18:3n-3. The optimized leaf drying time and temperature were 43 h and 70 ºC, respectively. The fatty acids (FA were investigated using gas chromatography equipped with a flame ionization detector and fused silica capillary column; FA were identified with standards and based on equivalent-chain-length. LNA and other FA were quantified against C21:0 internal standard. After dehydration, the amount of LNA, quantified in mg/100 g dry matter of dehydrated carrot leaves, were 984 mg.

Specific RNP capture with antisense LNA/DNA mixmers.

Science.gov (United States)

Rogell, Birgit; Fischer, Bernd; Rettel, Mandy; Krijgsveld, Jeroen; Castello, Alfredo; Hentze, Matthias W

2017-08-01

RNA-binding proteins (RBPs) play essential roles in RNA biology, responding to cellular and environmental stimuli to regulate gene expression. Important advances have helped to determine the (near) complete repertoires of cellular RBPs. However, identification of RBPs associated with specific transcripts remains a challenge. Here, we describe "specific ribonucleoprotein (RNP) capture," a versatile method for the determination of the proteins bound to specific transcripts in vitro and in cellular systems. Specific RNP capture uses UV irradiation to covalently stabilize protein-RNA interactions taking place at "zero distance." Proteins bound to the target RNA are captured by hybridization with antisense locked nucleic acid (LNA)/DNA oligonucleotides covalently coupled to a magnetic resin. After stringent washing, interacting proteins are identified by quantitative mass spectrometry. Applied to in vitro extracts, specific RNP capture identifies the RBPs bound to a reporter mRNA containing the Sex-lethal (Sxl) binding motifs, revealing that the Sxl homolog sister of Sex lethal (Ssx) displays similar binding preferences. This method also revealed the repertoire of RBPs binding to 18S or 28S rRNAs in HeLa cells, including previously unknown rRNA-binding proteins. © 2017 Rogell et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Tunable diode-pumped-LNA laser

International Nuclear Information System (INIS)

Cassimi, A.; Hardy, V.; Hamel, J.; Leduc, M.

1987-01-01

Diode-pumped crystals provided recently new compact laser devices. We report the first end pumping of a La x Nd 1-x MgAl 11 O 19 (LNA) crystal using a 200mW diode array (Spectra Diode Lab). We also report the first results obtained with a 1mW diode (SONY). This C.W. laser can be tuned from 1.048μm to 1.086μm. Without selective elements in the cavity, the laser emits around 1.054μm with a threshold of 24mW and a slope efficiency of 4.4% (output mirror of transmission T = 1%) when pumped by the diode array. With the selective elements, the threshold increases to 100mW and we obtain a power of 4mW for a pump power of 200mW

Fatty acid oxidation changes and the correlation with oxidative stress in different preeclampsia-like mouse models.

Directory of Open Access Journals (Sweden)

Xiaoyan Ding

Full Text Available BACKGROUND: Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD expression is decreased in placenta of some cases of preeclampsia (PE which may result in free fatty acid (FFA increased. High FFA level will induce oxidative stress, so abnormal long-chain fatty acid-oxidation may participate in the pathogenesis of PE through oxidative stress pathway. METHODS: PE-like groups were ApoC3 transgenic mice with abnormal fatty acid metabolism, classical PE-like models with injection of Nw-nitro-L-arginine-methyl ester (L-NA or lipopolysaccharide (LPS and the antiphospholipid syndrome (APS mouse model with β2GPI injection (ApoC3+NS, ApoC3+L-NA, L-NA, LPS and β2GPI groups. The control group was wild-type mice with normal saline injection. Except for β2GPI mice, the other mice were subdivided into pre-implantation (Pre and mid-pregnancy (Mid subgroups by injection time. RESULTS: All PE-like groups showed hypertension and proteinuria except ApoC3+NS mice only showed hypertension. Serum FFA levels increased significantly except in LPS group compared to controls (P<0.05. LCHAD mRNA and protein expression in the liver and placenta was significantly higher for ApoC3+NS, ApoC3+L-NA and β2GPI mice and lower for L-NA mice than controls (P<0.05 but did not differ between LPS mice and controls. P47phox mRNA and protein expression in the liver significantly increased in all PE-like groups except LPS group, while P47phox expression in the placenta only significantly increased in L-NA and β2GPI groups. CONCLUSIONS: Abnormal long-chain fatty acid-oxidation may play a different role in different PE-like models and in some cases participate in the pathogenesis of PE through oxidative stress pathway.

A Wide-Band High-Gain Compact SIS Receiver Utilizing a 300-μW SiGe IF LNA

Science.gov (United States)

Montazeri, Shirin; Grimes, Paul K.; Tong, Cheuk-Yu Edward; Bardin, Joseph C.

2017-06-01

Low-power low-noise amplifiers integrated with superconductor-insulator-superconductor (SIS) mixers are required to enable implementation of large-scale focal plane arrays. In this work, a 220-GHz SIS mixer has been integrated with a high-gain broad-band low-power IF amplifier into a compact receiver module. The low noise amplifier (LNA) was specifically designed to match to the SIS output impedance and contributes less than 7 K to the system noise temperature over the 4-8 GHz IF frequency range. A receiver noise temperature of 30-45 K was measured for a local oscillator frequency of 220 GHz over an IF spanning 4-8 GHz. The LNA power dissipation was only 300-μW. To the best of the authors' knowledge, this is the lowest power consumption reported for a high-gain wide-band LNA directly integrated with an SIS mixer.

A Small-Area Self-Biased Wideband CMOS Balun LNA with Noise Cancelling and Gain Enhancement

DEFF Research Database (Denmark)

Bruun, Erik; Andreani, Pietro; Custódio, J. R.

2010-01-01

In this paper we present a low-power and small-area balun LNA. The proposed inverter-based topology uses selfbiasing and noise cancelling, yielding a very robust LNA with a low NF. Comparing this circuit with a conventional inverterbased circuit, we obtain a ∼3 dB enhancement in voltage gain......, with improved robustness against PVT variations. Simulations results in a 130 nm CMOS technology show a 17.7dB voltage gain, nearly flat over a wide bandwidth (200MHz-1GHz), and an NF of approximately 4dB. The total power consumption is below 7.5 mW, with a very small die area of 0.007 mm2. All data...

Wideband Balun-LNA with Simultaneous Output Balancing, Noise-Canceling and Distortion-Canceling

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, D.M.W.; Nauta, Bram

2008-01-01

An inductorless low-noise amplifier (LNA) with active balun is proposed for multi-standard radio applications between 100 MHz and 6 GHz. It exploits a combination of a common-gate (CGH) stage and an admittance-scaled common-source (CS) stage with replica biasing to maximize balanced operation, while

An inductorless wideband LNA with a new noise canceling technique

OpenAIRE

MOGHADAM, POURIA PAZHOUHESH; ABRISHAMIFAR, ADIB

2017-01-01

An inductorless wideband low-noise amplifier (LNA) employing a new noise canceling technique for multistandard applications is presented. The main amplifier has a cascode common gate structure, which provides good input impedance matching and isolation. The proposed noise canceling technique not only improves the noise figure and power gain but also embeds a g$_{m}$-boosting technique in itself, which reduces the power consumption of the main amplifier. Using current-steering and ...

An inductorless wideband Balun-LNA in 65nm CMOS with balanced output

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Nauta, Bram; Leenaerts, D.M.W.

2007-01-01

Abstract — An inductorless LNA with active balun is designed for multi-standard radio applications between 100MHz and 6GHz. It exploits a combination of a common gate stage and a common source stage with replica biasing to maximize balanced operation. The NF is designed to be around 3dB by using the

High-performance CPW MMIC LNA using GaAs-based metamorphic HEMTs for 94-GHz applications

International Nuclear Information System (INIS)

Ryu, Keun-Kwan; Kim, Sung-Chan; An, Dan; Rhee, Jin-Koo

2010-01-01

In this paper, we report on a high-performance low-noise amplifier (LNA) using metamorphic high-electron-mobility transistor (MHEMT) technology for 94-GHz applications. The 100 nm x 60 μm MHEMT devices for the coplanar MMIC LNA exhibited DC characteristics with a drain current density of 655 mA/mm and an extrinsic transconductance of 720 mS/mm. The current gain cutoff frequency (f T ) and the maximum oscillation frequency (f max ) were 195 GHz and 305 GHz, respectively. Based on this MHEMT technology, coplanar 94-GHz MMIC LNAs were realized, achieving a small signal gain of more than 13 dB between 90 and 100 GHz and a small signal gain of 14.8 dB and a noise figure of 4.7 dB at 94 GHz.

Short (16-mer locked nucleic acid splice-switching oligonucleotides restore dystrophin production in Duchenne Muscular Dystrophy myotubes.

Directory of Open Access Journals (Sweden)

Vanessa Borges Pires

Full Text Available Splice-switching antisense oligonucleotides (SSOs offer great potential for RNA-targeting therapies, and two SSO drugs have been recently approved for treating Duchenne Muscular Dystrophy (DMD and Spinal Muscular Atrophy (SMA. Despite promising results, new developments are still needed for more efficient chemistries and delivery systems. Locked nucleic acid (LNA is a chemically modified nucleic acid that presents several attractive properties, such as high melting temperature when bound to RNA, potent biological activity, high stability and low toxicity in vivo. Here, we designed a series of LNA-based SSOs complementary to two sequences of the human dystrophin exon 51 that are most evolutionary conserved and evaluated their ability to induce exon skipping upon transfection into myoblasts derived from a DMD patient. We show that 16-mers with 60% of LNA modification efficiently induce exon skipping and restore synthesis of a truncated dystrophin isoform that localizes to the plasma membrane of patient-derived myotubes differentiated in culture. In sum, this study underscores the value of short LNA-modified SSOs for therapeutic applications.

Quantification of low-expressed mRNA using 5' LNA-containing real-time PCR primers

International Nuclear Information System (INIS)

Malgoyre, A.; Banzet, S.; Mouret, C.; Bigard, A.X.; Peinnequin, A.

2007-01-01

Real-time RT-PCR is the most sensitive and accurate method for mRNA quantification. Using specific recombinant DNA as a template, real-time PCR allows accurate quantification within a 7-log range and increased sensitivity below 10 copies. However, when using RT-PCR to quantify mRNA in biological samples, a stochastic off-targeted amplification can occur. Classical adjustments of assay parameters have minimal effects on such amplification. This undesirable amplification appears mostly to be dependent on specific to non-specific target ratio rather than on the absolute quantity of the specific target. This drawback, which decreases assay reliability, mostly appears when quantifying low-expressed transcript in a whole organ. An original primer design using properties of LNA allows to block off-target amplification. 5'-LNA substitution strengthens 5'-hybridization. Consequently on-target hybridization is stabilized and the probability for the off-target to lead to amplification is decreased

Synthesis and Excellent Duplex Stability of Oligonucleotides Containing 2'-Amino-LNA Functionalized with Galactose Units

DEFF Research Database (Denmark)

Kumar, Rajesh; Ries, Annika; Wengel, Jesper

2017-01-01

A convenient method for the preparation of oligonucleotides containing internally-attached galactose and triantennary galactose units has been developed based on click chemistry between 2'-N-alkyne 2'-amino-LNA nucleosides and azido-functionalized galactosyl building blocks. The synthesized...

An UWB LNA Design with PSO Using Support Vector Microstrip Line Model

Directory of Open Access Journals (Sweden)

Salih Demirel

2015-01-01

Full Text Available A rigorous and novel design procedure is constituted for an ultra-wideband (UWB low noise amplifier (LNA by exploiting the 3D electromagnetic simulator based support vector regression machine (SVRM microstrip line model. First of all, in order to design input and output matching circuits (IMC-OMC, source ZS and load ZL termination impedance of matching circuit, which are necessary to obtain required input VSWR (Vireq, noise (Freq, and gain (GTreq, are determined using performance characterisation of employed transistor, NE3512S02, between 3 and 8 GHz frequencies. After the determination of the termination impedance, to provide this impedance with IMC and OMC, dimensions of microstrip lines are obtained with simple, derivative-free, easily implemented algorithm Particle Swarm Optimization (PSO. In the optimization of matching circuits, highly accurate and fast SVRM model of microstrip line is used instead of analytical formulations. ADCH-80a is used to provide ultra-wideband RF choking in DC bias. During the design process, it is aimed that Vireq = 1.85, Freq = Fmin, and GTreq = GTmax all over operating frequency band. Measurements taken from the realized LNA demonstrate the success of this approximation over the band.

PMR investigation into complexes of lanthanum and lutetium with ethylenediaminediacetic acid

International Nuclear Information System (INIS)

Kostromina, N.A.; Novikova, L.B.

1975-01-01

Proton resonance spectra of ethylendiaminediacetic acid (EDDA) and EDDA mixtures with La and Lu as function of pH of solution was studied. Sequence of EDDA (A 2- ) protonation was established; cations H 3 A + and H 4 A 2+ were found; dissociation constants of above mentioned cations were determined. Formation of H 2 LnA 3+ , HLnA 2+ and LnA + complexes in EDDA-Ln (1:1) system was found. Difference in the bonds mobility of lanthanum and lutetium complexes was determined: lanthanum forms complexes with labile, lutetium with non-labile bonds. Information on complexes structure is collected. Acid dissociation constants of protonated complexes of lanthanum with EDDA were determined

Incorporation and profile of fatty acids in tilapia fillets (Oreochromis niloticus fed with tung oil

Directory of Open Access Journals (Sweden)

Elton Guntendorfer Bonafé

2013-02-01

Full Text Available The acceptance of tung oil enriched diet and the incorporation of conjugated linolenic acid - CLnA into fillets of Genetically Improved Farmed Tilapia (GIFT were investigated. The diet was well accepted, and after 10 days CLnA was incorporated into the fillets with a 1.02% content of total fatty acids (FA. In addition, biosynthesis of the conjugated linoleic acid isomers - CLA (0.31% of fillet total FA content from CLnA, and the presence of alpha-linolenic acid - LNA (1.08% of fillet total FA content, eicosapentaenoic acid - EPA (2.85% of fillet total FA content and docosahexaenoic acid - DHA (3.08% of fillet total FA content were observed. Therefore, the consumption of this fish can increase the intake of different FA (CLnA, CLA, LNA, EPA and DHA, which play an important role in human metabolism.

Biological activity and biotechnological aspects of locked nucleic acids

DEFF Research Database (Denmark)

Lundin, Karin E; Højland, Torben; Hansen, Bo

2013-01-01

Locked nucleic acid (LNA) is one of the most promising new nucleic acid analogues that has been produced under the past two decades. In this chapter, we have tried to cover many of the different areas, where this molecule has been used to improve the function of synthetic oligonucleotides (ONs). ...

Interim Report on Multiple Sequence Alignments and TaqMan Signature Mapping to Phylogenetic Trees

Energy Technology Data Exchange (ETDEWEB)

Gardner, S; Jaing, C

2012-03-27

The goal of this project is to develop forensic genotyping assays for select agent viruses, addressing a significant capability gap for the viral bioforensics and law enforcement community. We used a multipronged approach combining bioinformatics analysis, PCR-enriched samples, microarrays and TaqMan assays to develop high resolution and cost effective genotyping methods for strain level forensic discrimination of viruses. We have leveraged substantial experience and efficiency gained through year 1 on software development, SNP discovery, TaqMan signature design and phylogenetic signature mapping to scale up the development of forensics signatures in year 2. In this report, we have summarized the Taqman signature development for South American hemorrhagic fever viruses, tick-borne encephalitis viruses and henipaviruses, Old World Arenaviruses, filoviruses, Crimean-Congo hemorrhagic fever virus, Rift Valley fever virus and Japanese encephalitis virus.

Comparative crystallization and preliminary X-ray diffraction studies of locked nucleic acid and RNA stems of a tenascin C-binding aptamer

International Nuclear Information System (INIS)

Förster, Charlotte; Brauer, Arnd B. E.; Brode, Svenja; Schmidt, Kathrin S.; Perbandt, Markus; Meyer, Arne; Rypniewski, Wojciech; Betzel, Christian; Kurreck, Jens; Fürste, Jens P.; Erdmann, Volker A.

2006-01-01

Locked nucleic acid (LNA) nucleotides are RNA analogues with a useful additional conformational constraint; the current investigation will provide the first crystallographic view of an all-LNA duplex. The pharmacokinetic properties of an aptamer against the tumour-marker protein tenascin-C have recently been successfully improved by the introduction of locked nucleic acids (LNAs) into the terminal stem of the aptamer. Since it is believed that this post-SELEX optimization is likely to provide a more general route to enhance the in vitro and in vivo stability of aptamers, elucidation of the structural basis of this improvement was embarked upon. Here, the crystallographic and X-ray diffraction data of the isolated aptamer stem encompassed in a six-base-pair duplex both with and without the LNA modification are presented. The obtained all-LNA crystals belong to space group P4 1 2 1 2 or P4 3 2 1 2, with unit-cell parameters a = b = 52.80, c = 62.83 Å; the all-RNA crystals belong to space group R32, with unit-cell parameters a = b = 45.21, c = 186.97 Å, γ = 120.00°

Incorporation of conjugated linoleic acid (CLA and α-linolenic acid (LNA in pacu fillets

Directory of Open Access Journals (Sweden)

Deoclécio José Barilli

2014-03-01

Full Text Available The objective of this study was to evaluate the incorporation of conjugated linoleic acid and α-linolenic acid in fillets of pacu fish raised in net cages and fed diets enriched with these acids. The fish were fed for 49 days, and at the end of this period the fatty acid content in the fillets was determined by gas chromatography. Concentrations of α-linolenic acid, eicosapentaenoic acid, and the total omega-3 (n-3 fatty acid in the fillets increased, improving the n-6/n-3 ratio. In addition, the incorporation of conjugated linoleic acid in the fish fillets proved well established. This study showed that the use of diets enriched with conjugated linoleic acid and α-linolenic acid results in the incorporation of these acids in the of pacu fish fillets, improving their nutritional quality.

Towards Fluorescence In Vivo Hybridization (FIVH) Detection of H. pylori in Gastric Mucosa Using Advanced LNA Probes

DEFF Research Database (Denmark)

Fontenete, Sílvia; Leite, Marina; Guimarães, Nuno

2015-01-01

acid (LNA)/ 2' O-methyl RNA (2'OMe) probe using standard phosphoramidite chemistry and FISH hybridization was then successfully performed both on adhered and suspended bacteria at 37°C. In this work we simplified, shortened and adapted FISH to work at gastric pH values, meaning that the hybridization...... step now takes only 30 minutes and, in addition to the buffer, uses only urea and probe at non-toxic concentrations. Importantly, the sensitivity and specificity of the FISH method was maintained in the range of conditions tested, even at low stringency conditions (e.g., low pH). In conclusion......In recent years, there have been several attempts to improve the diagnosis of infection caused by Helicobacter pylori. Fluorescence in situ hybridization (FISH) is a commonly used technique to detect H. pylori infection but it requires biopsies from the stomach. Thus, the development of an in vivo...

Dietary High-Oleic Acid Soybean Oil Dose Dependently Attenuates Egg Yolk Content of n-3 Polyunsaturated Fatty Acids in Laying Hens Fed Supplemental Flaxseed Oil.

Science.gov (United States)

Elkin, Robert G; Kukorowski, Alexandra N; Ying, Yun; Harvatine, Kevin J

2018-02-01

Chickens can hepatically synthesize eicosapentaenoic acid (20:5 n-3) and docosahexaenoic acid (22:6 n-3) from α-linolenic acid (ALA; 18:3 n-3); however, the process is inefficient and competitively inhibited by dietary linoleic acid (LNA; 18:2 n-6). In the present study, the influence of dietary high-oleic acid (OLA; 18:1 n-9) soybean oil (HOSO) on egg and tissue deposition of ALA and n-3 polyunsaturated fatty acids (PUFA) synthesized from dietary ALA was investigated in laying hens fed a reduced-LNA base diet supplemented with high-ALA flaxseed oil (FLAX). We hypothesized that reducing the dietary level of LNA would promote greater hepatic conversion of ALA to very long-chain (VLC; >20C) n-3 PUFA, while supplemental dietary HOSO would simultaneously further enrich eggs with OLA without influencing egg n-3 PUFA contents. Nine 51-week-old hens each were fed 0, 10, 20, or 40 g HOSO/kg diet for 12 weeks. Within each group, supplemental dietary FLAX was increased every 3 weeks from 0 to 10 to 20 to 40 g/kg diet. Compared to controls, dietary FLAX maximally enriched the total n-3 and VLC n-3 PUFA contents in egg yolk by 9.4-fold and 2.2-fold, respectively, while feeding hens 40 g HOSO/kg diet maximally attenuated the yolk deposition of ALA, VLC n-3 PUFA, and total n-3 PUFA by 37, 15, and 32%, respectively. These results suggest that dietary OLA is not neutral with regard to the overall process by which dietary ALA is absorbed, metabolized, and deposited into egg yolk, either intact or in the form of longer-chain/more unsaturated n-3 PUFA derivatives. © 2018 AOCS.

Activity and phylogenetic diversity of bacterial cells with high and low nucleic acid content and electron transport system activity in an upwelling ecosystem.

Science.gov (United States)

Longnecker, K; Sherr, B F; Sherr, E B

2005-12-01

We evaluated whether bacteria with higher cell-specific nucleic acid content (HNA) or an active electron transport system, i.e., positive for reduction of 5-cyano-2,3-ditolyl tetrazolium chloride (CTC), were responsible for the bulk of bacterioplankton metabolic activity. We also examined whether the phylogenetic diversity of HNA and CTC-positive cells differed from the diversity of Bacteria with low nucleic acid content (LNA). Bacterial assemblages were sampled both in eutrophic shelf waters and in mesotrophic offshore waters in the Oregon coastal upwelling region. Cytometrically sorted HNA, LNA, and CTC-positive cells were assayed for their cell-specific [3H]leucine incorporation rates. Phylogenetic diversity in sorted non-radioactively labeled samples was assayed using denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA genes. Cell-specific rates of leucine incorporation of HNA and CTC-positive cells were on average only slightly greater than the cell-specific rates of LNA cells. HNA cells accounted for most bacterioplankton substrate incorporation due to high abundances, while the low abundances of CTC-positive cells resulted in only a small contribution by these cells to total bacterial activity. The proportion of the total bacterial leucine incorporation attributable to LNA cells was higher in offshore regions than in shelf waters. Sequence data obtained from DGGE bands showed broadly similar phylogenetic diversity across HNA, LNA, and CTC-positive cells, with between-sample and between-region variability in the distribution of phylotypes. Our results suggest that LNA bacteria are not substantially different from HNA bacteria in either cell-specific rates of substrate incorporation or phylogenetic composition and that they can be significant contributors to bacterial metabolism in the sea.

Biochemical responses to dietary α-linolenic acid restriction proceed differently among brain regions in mice.

Science.gov (United States)

Miyazawa, Daisuke; Yasui, Yuko; Yamada, Kazuyo; Ohara, Naoki; Okuyama, Harumi

2011-08-01

Previously, we noted that the dietary restriction of α-linolenic acid (ALA, n-3) for 4 weeks after weaning brought about significant decreases in the BDNF content and p38 MAPK activity in the striatum of mice, but not in the other regions of the brain, compared with an ALA- and linoleic acid (LNA, n-6)-adequate diet. In this study, we examined whether a prolonged dietary manipulation induces biochemical changes in other regions of the brain as well. Mice were fed a safflower oil (SAF) diet (ALA-restricted, LNA-adequate) or a perilla oil (PER) diet (containing adequate amounts of ALA and LNA) for 8 weeks from weaning. The docosahexaenoic acid (DHA, 22:6n-3) contents and p38 MAPK activities in the cerebral cortex, striatum and hippocampus were significantly lower in the SAF group. The BDNF contents and protein kinase C (PKC) activities in the cerebral cortex as well as in the striatum, but not in the hippocampus, were significantly lower in the SAF group. These data indicate that the biochemical changes induced by the dietary restriction of ALA have a time lag in the striatum and cortex, suggesting that the signal is transmitted through decreased p38 MAPK activity and BDNF content and ultimately decreased PKC activity.

A 5.4mW GPS CMOS quadrature front-end based on a single-stage LNA-mixer-VCO

DEFF Research Database (Denmark)

Liscidini, Amtonio; Mazzanti, Andrea; Tonietto, Riccardo

2006-01-01

A GPS RF front-end combines the LNA, mixer, and VCO in a single stage and can operate from a 1.2V supply. The chip is implemented in a 0.13um CMOS process and occupies 1.5mm2 active area. It consumes 5.4mW with a 4.8dB NF, 36dB gain, and a P1dB of -31dBm.......A GPS RF front-end combines the LNA, mixer, and VCO in a single stage and can operate from a 1.2V supply. The chip is implemented in a 0.13um CMOS process and occupies 1.5mm2 active area. It consumes 5.4mW with a 4.8dB NF, 36dB gain, and a P1dB of -31dBm....

Docosahexaenoic acid (DHA, essentiality and requirements: why and how to provide supplementation

Directory of Open Access Journals (Sweden)

Nieto, Susana

2006-06-01

Full Text Available Lipids comprize from 50-60% of the structural matter of the brain and docosahexaenoic acid (C22:6, DHA is the most  important omega-3 long-chain polyunsaturated fatty acid in the brain phospholipids comprizing 25% of the total fatty acids of the grey matter. The majority of the DHA present in the human brain is incorporated during the brain growth spurt which starts at week 26 of gestation and imposes a high demand for the fatty acid until about 2 years of age. DHA is required during brain development when neuronal and glial differentiation and migration, and active myelination and synaptogenesis take place. The fatty acid must be incorporated into the brain lipids as preformed DHA because less than 5% of its precursor (alpha linolenic acid, LNA is converted to DHA. The human foetus has a limited ability to synthesize DHA from LNA, and therefore it must be largely supplied from maternal sources. Maternal DHA available for foetal nutrition can be provided from three main sources: adipose tissue, which is the main reservoir for the fatty acid; through biosynthesis from the precursor LNA, which occurs mainly in the liver; and as preformed DHA from dietary sources. In the postnatal period DHA is provided by the mother to the newborn through milk secretion. Western nutrition provides low LNA and DHA and Expert Nutrition Committees suggest that mothers should receive DHA supplementation during pregnancy and lactation. At present DHA supplementation can be provided from different sources: as purified free DHA, as an ethyl ester derivative, extracted from single-cell algae oils, from egg yolk phospholipids, or in the form of sn-2 DHA monoacylglycerol. In this review we revise and discuss the evidence of DHA requirements for the newborn, the need for maternal supplementation during pregnancy and nursing, and the alternatives at present for providing DHA supplementation.Los lípidos comprenden entre el 50-60% de la estructura del cerebro, y el �

Does the high nucleic acid content of individual bacterial cells allow us to discriminate between active cells and inactive cells in aquatic systems?

Science.gov (United States)

Lebaron, P; Servais, P; Agogué, H; Courties, C; Joux, F

2001-04-01

The nucleic acid contents of individual bacterial cells as determined with three different nucleic acid-specific fluorescent dyes (SYBR I, SYBR II, and SYTO 13) and flow cytometry were compared for different seawater samples. Similar fluorescence patterns were observed, and bacteria with high apparent nucleic acid contents (HNA) could be discriminated from bacteria with low nucleic acid contents (LNA). The best discrimination between HNA and LNA cells was found when cells were stained with SYBR II. Bacteria in different water samples collected from seven freshwater, brackish water, and seawater ecosystems were prelabeled with tritiated leucine and then stained with SYBR II. After labeling and staining, HNA, LNA, and total cells were sorted by flow cytometry, and the specific activity of each cellular category was determined from leucine incorporation rates. The HNA cells were responsible for most of the total bacterial production, and the specific activities of cells in the HNA population varied between samples by a factor of seven. We suggest that nucleic acid content alone can be a better indicator of the fraction of growing cells than total counts and that this approach should be combined with other fluorescent physiological probes to improve detection of the most active cells in aquatic systems.

Starch and oil in the donor cow diet and starch in substrate differently affect the in vitro ruminal biohydrogenation of linoleic and linolenic acids.

Science.gov (United States)

Zened, A; Troegeler-Meynadier, A; Nicot, M C; Combes, S; Cauquil, L; Farizon, Y; Enjalbert, F

2011-11-01

Trans isomers of fatty acids exhibit different health properties. Among them, trans-10,cis-12 conjugated linoleic acid has negative effects on milk fat production and can affect human health. A shift from the trans-11 to the trans-10 pathway of biohydrogenation (BH) can occur in the rumen of dairy cows receiving high-concentrate diets, especially when the diet is supplemented with highly unsaturated fat sources. The differences of BH patterns between linoleic acid (LeA) and linolenic acid (LnA) in such ruminal conditions remain unknown; thus, the aim of this work was to investigate in vitro the effects of starch and sunflower oil in the diet of the donor cows and starch level in the incubates on the BH patterns and efficiencies of LeA and LnA. The design was a 4 × 4 Latin square design with 4 cows, 4 periods, and 4 diets with combinations of 21 or 34% starch and 0 or 5% sunflower oil. The rumen content of each cow during each period was incubated with 4 substrates, combining 2 starch levels and either LeA or LnA addition. Capillary electrophoresis single-strand conformation polymorphism of incubates showed that dietary starch decreased the diversity of the bacterial community and the high-starch plus oil diet modified its structure. High-starch diets poorly affected isomerization and first reduction of LeA and LnA, but decreased the efficiencies of trans-11,cis-15-C18:2 and trans C18:1 reduction. Dietary sunflower oil increased the efficiency of LeA isomerization but decreased the efficiency of trans C18:1 reduction. An interaction between dietary starch and dietary oil resulted in the highest trans-10 isomers production in incubates when the donor cow received the high-starch plus oil diet. The partition between trans-10 and trans-11 isomers was also affected by an interaction between starch level and the fatty acid added to the incubates, showing that the trans-10 shift only occurred with LeA, whereas LnA was mainly hydrogenated via the more usual trans-11

Branched DNA nanostructures efficiently stabilised and monitored by novel pyrene-perylene 2'-α-l-amino-LNA FRET pairs

DEFF Research Database (Denmark)

Astakhova, I Kira; Santhosh Kumar, T; Campbell, Meghan A

2013-01-01

Novel pyrene-perylene α-l-LNA FRET pairs described herein effectively detect assembly of 2- and 3-way branched DNA nanostructures prepared by postsynthetic microwave-assisted CuAAC click chemistry. The fluorescent signalling of assembly by internally positioned FRET pairs is achieved with low...

Design of a low-power 433/915-MHz RF front-end with a current-reuse common-gate LNA

International Nuclear Information System (INIS)

Jing Yiou; Lu Huaxiang

2013-01-01

This paper presents a wideband RF front-end with novel current-reuse wide band low noise amplifier (LNA), current-reuse V—I converter, active double balanced mixer and transimpedance amplifier for short range device (SRD) applications. With the proposed current-reuse LNA, the DC consumption of the front-end reduces considerably while maintaining sufficient performance needed by SRD devices. The RF front-end was fabricated in 0.18 μm RFCMOS process and occupies a silicon area of just 0.11 mm 2 . Operating in 433 MHz band, the measurement results show the RF front-end achieves a conversion gain of 29.7 dB, a double side band noise figure of 9.7 dB, an input referenced third intercept point of −24.9 dBm with only 1.44 mA power consumption from 1.8 V supply. Compared to other reported front-ends, it has an advantage in power consumption. (semiconductor integrated circuits)

Enhancing the intestinal absorption of low molecular weight chondroitin sulfate by conjugation with α-linolenic acid and the transport mechanism of the conjugates.

Science.gov (United States)

Xiao, Yuliang; Li, Pingli; Cheng, Yanna; Zhang, Xinke; Sheng, Juzheng; Wang, Decai; Li, Juan; Zhang, Qian; Zhong, Chuanqing; Cao, Rui; Wang, Fengshan

2014-04-25

The purpose of this report was to demonstrate the effect of amphiphilic polysaccharides-based self-assembling micelles on enhancing the oral absorption of low molecular weight chondroitin sulfate (LMCS) in vitro and in vivo, and identify the transepithelial transport mechanism of LMCS micelles across the intestinal barrier. α-Linolenic acid-low molecular weight chondroitin sulfate polymers(α-LNA-LMCS) were successfully synthesized, and characterized by FTIR, (1)HNMR, TGA/DSC, TEM, laser light scattering and zeta potential. The significant oral absorption enhancement and elimination half-life (t₁/₂) extension of LNA-LMCS2 in rats were evidenced by intragastric administration in comparison with CS and LMCS. Caco-2 transport studies demonstrated that the apparent permeability coefficient (Papp) of LNA-LMCS2 was significantly higher than that of CS and LMCS (p<0.001), and no significant effects on the overall integrity of the monolayer were observed during the transport process. In addition, α-LNA-LMCS micelles accumulated around the cell membrane and intercellular space observed by confocal laser scanning microscope (CLSM). Furthermore, evident alterations in the F-actin cytoskeleton were detected by CLSM observation following the treatment of the cell monolayers with α-LNA-LMCS micelles, which further certified the capacity of α-LNA-LMCS micelles to open the intercellular tight junctions rather than disrupt the overall integrity of the monolayer. Therefore, LNA-LMCS2 with low cytotoxicity and high bioavailability might be a promising substitute for CS in clinical use, such as treating osteoarthritis, atherosclerosis, etc. Copyright © 2014 Elsevier B.V. All rights reserved.

Real-time TaqMan polymerase chain reaction to quantify the effects ...

African Journals Online (AJOL)

TaqMan polymerase chain reaction was developed to quantify the number of Bifidobacterium. We used this assay to detect genomic DNA of Bifidobacterium in the intestinal tract digesta of piglets, including duodenum, jejunum, ileum, cecum and colon. Our results indicated that, developed new real-time quantitative PCR ...

Crystallization and X-ray diffraction analysis of an ‘all-locked’ nucleic acid duplex derived from a tRNASer microhelix

International Nuclear Information System (INIS)

Behling, Katja; Eichert, André; Fürste, Jens P.; Betzel, Christian; Erdmann, Volker A.; Förster, Charlotte

2009-01-01

A completely ‘all-locked’ nucleic acid duplex was designed from an E. coli tRNA Ser microhelix. The helix consists exclusively of LNA building blocks and was crystallized. The crystals diffracted to 1.9 Å resolution. Modified nucleic acids are of great interest with respect to their nuclease resistance and enhanced thermostability. In therapeutical and diagnostic applications, such molecules can substitute for labile natural nucleic acids that are targeted against particular diseases or applied in gene therapy. The so-called ‘locked nucleic acids’ contain modified sugar moieties such as 2′-O,4′-C-methylene-bridged β-d-ribofuranose and are known to be very stable nucleic acid derivatives. The structure of locked nucleic acids in single or multiple LNA-substituted natural nucleic acids and in LNA–DNA or LNA–RNA heteroduplexes has been well investigated, but the X-ray structure of an ‘all-locked’ nucleic acid double helix has not been described to date. Here, the crystallization and X-ray diffraction data analysis of an ‘all-locked’ nucleic acid helix, which was designed as an LNA originating from a tRNA Ser microhelix RNA structure, is presented. The crystals belonged to space group C2, with unit-cell parameters a = 77.91, b = 40.74, c = 30.06 Å, β = 91.02°. A high-resolution and a low-resolution data set were recorded, with the high-resolution data showing diffraction to 1.9 Å resolution. The crystals contained two double helices per asymmetric unit, with a Matthews coefficient of 2.48 Å 3 Da −1 and a solvent content of 66.49% for the merged data

Synthesis and study of rare earth complexes with ortho-hydroxyphenyliminodiacetic acid containing lactone ring

International Nuclear Information System (INIS)

Martynenko, L.I.; Mitrofanova, N.D.; Muratova, N.M.; Kurbatova, S.V.

1978-01-01

Solid complex compounds of o-oxyphenyliminodiacetic acid with rare earth elements of the composition of LnA 2 Clx6H 2 O and LnA 3 x5H 2 O (where Ln=La, Pr, Nd, Eu, Dy, Er, and Y) not described earlier, have been synthesized. The thermographic analysis of the compounds has been performed. It is shown by infrared spectroscopy that a lactone ring is retained in the dicomplex structure. The presence of the absorption bands of non-ionized COOH-groups in the infrared spectra of tricomplexonates of heavy r.e.e. points to opening of the lactone ring in the ligand part

Effects of oils rich in linoleic and α-linolenic acids on fatty acid profile and gene expression in goat meat.

Science.gov (United States)

Ebrahimi, Mahdi; Rajion, Mohamed Ali; Goh, Yong Meng

2014-09-24

Alteration of the lipid content and fatty acid (FA) composition of foods can result in a healthier product. The aim of this study was to determine the effect of flaxseed oil or sunflower oil in the goat diet on fatty acid composition of muscle and expression of lipogenic genes in the semitendinosus (ST) muscle. Twenty-one entire male Boer kid goats were fed diets containing different levels of linoleic acid (LA) and α-linolenic acid (LNA) for 100 days. Inclusion of flaxseed oil increased (p goats to enrich goat meat with n-3 fatty acids, upregulate the PPARα and PPARγ, and downregulate the SCD gene expression.

T.I.M.S: TaqMan Information Management System, tools to organize data flow in a genotyping laboratory

Science.gov (United States)

Monnier, Stéphanie; Cox, David G; Albion, Tim; Canzian, Federico

2005-01-01

Background Single Nucleotide Polymorphism (SNP) genotyping is a major activity in biomedical research. The Taqman technology is one of the most commonly used approaches. It produces large amounts of data that are difficult to process by hand. Laboratories not equipped with a Laboratory Information Management System (LIMS) need tools to organize the data flow. Results We propose a package of Visual Basic programs focused on sample management and on the parsing of input and output TaqMan files. The code is written in Visual Basic, embedded in the Microsoft Office package, and it allows anyone to have access to those tools, without any programming skills and with basic computer requirements. Conclusion We have created useful tools focused on management of TaqMan genotyping data, a critical issue in genotyping laboratories whithout a more sophisticated and expensive system, such as a LIMS. PMID:16221298

T.I.M.S: TaqMan Information Management System, tools to organize data flow in a genotyping laboratory

Directory of Open Access Journals (Sweden)

Albion Tim

2005-10-01

Full Text Available Abstract Background Single Nucleotide Polymorphism (SNP genotyping is a major activity in biomedical research. The Taqman technology is one of the most commonly used approaches. It produces large amounts of data that are difficult to process by hand. Laboratories not equipped with a Laboratory Information Management System (LIMS need tools to organize the data flow. Results We propose a package of Visual Basic programs focused on sample management and on the parsing of input and output TaqMan files. The code is written in Visual Basic, embedded in the Microsoft Office package, and it allows anyone to have access to those tools, without any programming skills and with basic computer requirements. Conclusion We have created useful tools focused on management of TaqMan genotyping data, a critical issue in genotyping laboratories whithout a more sophisticated and expensive system, such as a LIMS.

Identification of field caught Anopheles gambiae s.s. and Anopheles arabiensis by TaqMan single nucleotide polymorphism genotyping

Directory of Open Access Journals (Sweden)

Bayoh Nabie M

2007-02-01

Full Text Available Abstract Background Identification of Anopheles gambiae s.s. and Anopheles arabiensis from field-collected Anopheles gambiae s.l. is often necessary in basic and applied research, and in operational control programmes. The currently accepted method involves use of standard polymerase chain reaction amplification of ribosomal DNA (rDNA from the 3' 28S to 5' intergenic spacer region of the genome, and visual confirmation of amplicons of predicted size on agarose gels, after electrophoresis. This report describes development and evaluation of an automated, quantitative PCR method based upon TaqMan™ single nucleotide polymorphism (SNP genotyping. Methods Standard PCR, and TaqMan SNP genotyping with newly designed primers and fluorophore-labeled probes hybridizing to sequences of complementary rDNA specific for either An. gambiae s.s. or An. arabiensis, were conducted in three experiments involving field-collected An. gambiae s.l. from western Kenya, and defined laboratory strains. DNA extraction was from a single leg, sonicated for five minutes in buffer in wells of 96-well PCR plates. Results TaqMan SNP genotyping showed a reaction success rate, sensitivity, and species specificity comparable to that of standard PCR. In an extensive field study, only 29 of 3,041 (0.95% were determined to be hybrids by TaqMan (i.e., having rDNA sequences from both species, however, all but one were An. arabiensis by standard PCR, suggesting an acceptably low (ca. 1% error rate for TaqMan genotyping in mistakenly identifying species hybrids. Conclusion TaqMan SNP genotyping proved to be a sensitive and rapid method for identification of An. gambiae s.l. and An. arabiensis, with a high success rate, specific results, and congruence with the standard PCR method.

Real-time PCR for type-specific identification of herpes simplex in clinical samples: evaluation of type-specific results in the context of CNS diseases.

Science.gov (United States)

Meylan, Sylvain; Robert, Daniel; Estrade, Christine; Grimbuehler, Valérie; Péter, Olivier; Meylan, Pascal R; Sahli, Roland

2008-02-01

HSV-1 and HSV-2 cause CNS infections of dissimilar clinico-pathological characteristics with prognostic and therapeutic implications. To validate a type-specific real-time PCR that uses MGB/LNA Taqman probes and to review the virologico-clinical data of 25 eligible patients with non-neonatal CNS infections. This real-time PCR was evaluated against conventional PCR (26 CSF and 20 quality controls), and LightCycler assay (51 mucocutaneous, 8 CSF and 32 quality controls) and culture/immunofluorescence (75 mucocutaneous) to assess typing with independent methods. Taqman real-time PCR detected 240 HSV genomes per ml CSF, a level appropriate for the management of patients, and provided unambiguous typing for the 104 positive (62 HSV-1 and 42 HSV-2) out the 160 independent clinical samples tested. HSV type diagnosed by Taqman real-time PCR predicted final diagnosis (meningitis versus encephalitis/meningoencephalitis, p<0.001) in 24/25 patients at time of presentation, in contrast to clinical evaluation. Our real-time PCR, as a sensitive and specific means for type-specific HSV diagnosis, provided rapid prognostic information for patient management.

Hydrogel-Assisted Antisense LNA Gapmer Delivery for In Situ Gene Silencing in Spinal Cord Injury

DEFF Research Database (Denmark)

Moreno, Pedro M.D.; Ferreira, Ana R.; Salvador, Daniela

2018-01-01

)-modified AON gapmers in combination with a fibrin hydrogel bridging material to induce gene silencing in situ at a SCI lesion site. LNA gapmers were effectively developed against two promising gene targets aiming at enhancing axonal regeneration—RhoA and GSK3β. The fibrin-matrix-assisted AON delivery system......After spinal cord injury (SCI), nerve regeneration is severely hampered due to the establishment of a highly inhibitory microenvironment at the injury site, through the contribution of multiple factors. The potential of antisense oligonucleotides (AONs) to modify gene expression at different levels...

Locked Nucleic Acid-Based In Situ Hybridization Reveals miR-7a as a Hypothalamus-Enriched MicroRNA with a Distinct Expression Pattern

DEFF Research Database (Denmark)

Herzer, S; Silahtaroglu, A; Meister, B

2012-01-01

, a part of the brain that controls vital bodily functions, we employed locked nucleic acid (LNA) - fluorescent in situ hybridization (FISH). The expression pattern of the mature miRNAs miR-7a, miR-7b, miR-137 and miR-153 in mouse brain tissue sections was investigated. Whereas all studied miRNAs were......R-7a expression was particularly prominent in the subfornical organ, suprachiasmatic, paraventricular, periventricular, supraoptic, dorsomedial and arcuate nuclei. Identical expression patterns for miR-7a was seen in mouse and rat hypothalamus. By combining LNA-FISH with immunohistochemistry...

Development and evaluation of Taqman assays for the differentiation of Dickeya (sub)species

NARCIS (Netherlands)

Wolf, van der J.M.; Haas, de B.H.; Hoof, van R.A.; Haan, de E.G.; Bovenkamp, van den G.W.

2014-01-01

TaqMan assays were developed for the detection of seven Dickeya species, namely D. dianthicola, D. dadantii, D. paradisiaca, D. chrysanthemi, D. zeae, D. dieffenbachiae and D. solani. Sequences of the gene coding for dnaX were used for the design of primers and probes. In studies with axenic

Antagonism of microRNA-122 in mice by systemically administered LNA-antimiR leads to up-regulation of a large set of predicted target mRNAs in the liver

DEFF Research Database (Denmark)

Elmen, Joachim; Lindow, Morten; Silahtaroglu, Asli

2008-01-01

’end of miR-122 leads to specific, dose-dependent silencing of miR-122 and shows no hepatotoxicity in mice. Antagonism of miR-122 is due to formation of stable heteroduplexes between the LNA-antimiR and miR-122 as detected by northern analysis. Fluorescence in situ hybridization demonstrated uptake...... of the LNA-antimiR in mouse liver cells, which was accompanied by markedly reduced hybridization signals for mature miR-122 in treated mice. Functional antagonism of miR-122 was inferred from a low cholesterol phenotype and derepression within 24 h of 199 liver mRNAs showing significant enrichment for mi...

Comparison of allelic discrimination by dHPLC, HRM, and TaqMan in the detection of BRAF mutation V600E.

Science.gov (United States)

Carbonell, Pablo; Turpin, María C; Torres-Moreno, Daniel; Molina-Martínez, Irene; García-Solano, José; Perez-Guillermo, Miguel; Conesa-Zamora, Pablo

2011-09-01

The V600E mutation in the BRAF oncogene is associated with colorectal carcinomas, with mismatch-repair deficiency and, recently, with nonresponse to epidermal growth factor receptor inhibitor therapy. The use of reliable techniques for its detection is important. The aim of our study was to compare the performance characteristics in V600E detection of denaturing high-performance liquid chromatography (dHPLC) and high-resolution melting (HRM) with TaqMan allelic discrimination as well as direct-sequencing methods in a series of 195 colorectal paraffin-embedded specimens up to the age of 15 years. The effectiveness for obtaining results on mutation status was best using TaqMan (96.9%), followed by dHPLC (93.3%), HRM (88.7%), and sequencing (88.2%). In general, TaqMan was best for analyzing older tissues, whereas sequencing was the least efficient. Heterozygotic V600E was detected in 11.6%, 9.9%, 11.6%, and 9.9% of tissues using TaqMan, dHPLC, HRM, and sequencing, respectively. Result concordances between dHPLC and TaqMan or sequencing were excellent (κ = 0.9411 and κ = 0.8988, respectively); for HRM, the concordances were good (κ = 0.7973 and κ = 0.7488, respectively). By using DNA dilutions from tumor tissue, a minimum of 10% of V600E harboring cancer content was required for the analysis by dHPLC and HRM. dHPLC could detect four non-V600E mutations, whereas HRM detected one. Our results indicate that dHPLC and HRM are techniques that can be reliably used for the detection of the BRAFV600E mutation in archival paraffin-embedded tissues. Copyright © 2011 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Locked nucleic acid inhibits amplification of contaminating DNA in real-time PCR

DEFF Research Database (Denmark)

Hummelshoj, Lone; Ryder, Lars P; Madsen, Hans O

2005-01-01

and real-time PCR, the addition of LNA showed blocking of the amplification of genomic XBP1 but not cDNA XBP1. To test the effect of melting temperature (Tm) on the LNA, we investigated the number of LNA nucleotides that could be replaced with DNA nucleotides and still retain the blocking activity. More...

MeltMan: Optimization, Evaluation, and Universal Application of a qPCR System Integrating the TaqMan qPCR and Melting Analysis into a Single Assay

Science.gov (United States)

Nagy, Alexander; Černíková, Lenka; Vitásková, Eliška; Křivda, Vlastimil; Dán, Ádám; Dirbáková, Zuzana; Jiřincová, Helena; Procházka, Bohumír; Sedlák, Kamil; Havlíčková, Martina

2016-01-01

In the present work, we optimised and evaluated a qPCR system integrating 6-FAM (6-carboxyfluorescein)-labelled TaqMan probes and melting analysis using the SYTO 82 (S82) DNA binding dye in a single reaction. We investigated the influence of the S82 on various TaqMan and melting analysis parameters and defined its optimal concentration. In the next step, the method was evaluated in 36 different TaqMan assays with a total of 729 paired reactions using various DNA and RNA templates, including field specimens. In addition, the melting profiles of interest were correlated with the electrophoretic patterns. We proved that the S82 is fully compatible with the FAM-TaqMan system. Further, the advantages of this approach in routine diagnostic TaqMan qPCR were illustrated with practical examples. These included solving problems with flat or other atypical amplification curves or even false negativity as a result of probe binding failure. Our data clearly show that the integration of the TaqMan qPCR and melting analysis into a single assay provides an additional control option as well as the opportunity to perform more complex analyses, get more data from the reactions, and obtain analysis results with higher confidence. PMID:27031831

POLARIMETRIA ÓPTICA E MODELAGEM DE POLARES OBSERVADAS NO OPD/LNA NO PERÍODO DE 2010-2012

Directory of Open Access Journals (Sweden)

Karleyne M. G. Silva Silva

2013-12-01

Full Text Available Neste trabalho apresentamos os primeiros resultados do estudo de uma nova amostra de 7candidatas a polares a partir de dados polarimétricos obtidos no observatório do Pico dos Dias / LNA. Dos 4objetos analisados até o momento, confirmamos a presença de polarização alta e variável em 3, o que indica apresença de emissão ciclotrônica e sua classificação como polares. Esses dados serão modelados utilizando-seo código CYCLOPS.

POLARIMETRIA ÓPTICA E MODELAGEM DE POLARES OBSERVADAS NO OPD/LNA NO PERÍODO DE 2010-2012

OpenAIRE

Silva, Karleyne M. G. Silva; Divisão de Astrofísica - Instituto Nacional de Pesquisas Espacias - INPE; Rodrigues, Cláudia V.; INPE; Costa, Joaquim E. R.; INPE; Cieslinski, Deonísio; INPE; Almeida, Leonardo A.; INPE; Magalhães, Victor S.; INPE

2013-01-01

Neste trabalho apresentamos os primeiros resultados do estudo de uma nova amostra de 7candidatas a polares a partir de dados polarimétricos obtidos no observatório do Pico dos Dias / LNA. Dos 4objetos analisados até o momento, confirmamos a presença de polarização alta e variável em 3, o que indica apresença de emissão ciclotrônica e sua classificação como polares. Esses dados serão modelados utilizando-seo código CYCLOPS.

Novel TaqMan real-time polymerase chain reaction assay for verifying the authenticity of meat and commercial meat products from game birds.

Science.gov (United States)

Rojas, María; González, Isabel; Pavón, Miguel Angel; Pegels, Nicolette; Lago, Adriana; Hernández, Pablo E; García, Teresa; Martín, Rosario

2010-06-01

Species-specific real-time polymerase chain reaction (PCR) assays using TaqMan probes have been developed for verifying the labeling of meat and commercial meat products from game birds, including quail, pheasant, partridge, guinea fowl, pigeon, Eurasian woodcock and song thrush. The method combines the use of species-specific primers and TaqMan probes that amplify small fragments (amplicons meat products from the target species demonstrated the suitability of the assay for the detection of the target DNAs.

Mismatch discrimination of lipidated DNA and LNA-probes (LiNAs) in hybridization-controlled liposome assembly

DEFF Research Database (Denmark)

Jakobsen, Ulla; Vogel, Stefan

2016-01-01

Assays for mismatch discrimination and detection of single nucleotide variations by hybridization-controlled assembly of liposomes, which do not require tedious surface chemistry, are versatile for both DNA and RNA targets. We report herein a comprehensive study on different DNA and LNA (locked...... assay in the context of mismatch discrimination and SNP detection are presented. The advantages of membrane-anchored LiNA-probes compared to chemically attached probes on solid nanoparticles (e.g. gold nanoparticles) are described. Key functionalities such as non-covalent attachment of LiNA probes...... without the need for long spacers and the inherent mobility of membrane-anchored probes in lipid-bilayer membranes will be described for several different probe designs....

Evaluation of a TaqMan Array Card for Detection of Central Nervous System Infections.

Science.gov (United States)

Onyango, Clayton O; Loparev, Vladimir; Lidechi, Shirley; Bhullar, Vinod; Schmid, D Scott; Radford, Kay; Lo, Michael K; Rota, Paul; Johnson, Barbara W; Munoz, Jorge; Oneko, Martina; Burton, Deron; Black, Carolyn M; Neatherlin, John; Montgomery, Joel M; Fields, Barry

2017-07-01

Infections of the central nervous system (CNS) are often acute, with significant morbidity and mortality. Routine diagnosis of such infections is limited in developing countries and requires modern equipment in advanced laboratories that may be unavailable to a number of patients in sub-Saharan Africa. We developed a TaqMan array card (TAC) that detects multiple pathogens simultaneously from cerebrospinal fluid. The 21-pathogen CNS multiple-pathogen TAC (CNS-TAC) assay includes two parasites ( Balamuthia mandrillaris and Acanthamoeba ), six bacterial pathogens ( Streptococcus pneumonia e, Haemophilus influenzae , Neisseria meningitidis , Mycoplasma pneumoniae , Mycobacterium tuberculosis , and Bartonella ), and 13 viruses (parechovirus, dengue virus, Nipah virus, varicella-zoster virus, mumps virus, measles virus, lyssavirus, herpes simplex viruses 1 and 2, Epstein-Barr virus, enterovirus, cytomegalovirus, and chikungunya virus). The card also includes human RNase P as a nucleic acid extraction control and an internal manufacturer control, GAPDH (glyceraldehyde-3-phosphate dehydrogenase). This CNS-TAC assay can test up to eight samples for all 21 agents within 2.5 h following nucleic acid extraction. The assay was validated for linearity, limit of detection, sensitivity, and specificity by using either live viruses (dengue, mumps, and measles viruses) or nucleic acid material (Nipah and chikungunya viruses). Of 120 samples tested by individual real-time PCR, 35 were positive for eight different targets, whereas the CNS-TAC assay detected 37 positive samples across nine different targets. The CNS-TAC assays showed 85.6% sensitivity and 96.7% specificity. Therefore, the CNS-TAC assay may be useful for outbreak investigation and surveillance of suspected neurological disease. Copyright © 2017 American Society for Microbiology.

Genotyping of Hepatitis C virus isolated from hepatitis patients in Southeast of Iran by taqman realtime PCR

International Nuclear Information System (INIS)

Farivar, T.N.; Johari, P.

2011-01-01

Objectives: To check TaqMan Realtime PCR in detecting genotypes of hepatitis C virus in Iran. Methods: From July 2007 to April 2009, HCV genotyping was done on 52 patients who were referred to Research Centre for infectious Disease and Tropical Medicine, in Bou-Ali Hospital, Zahedan University of Medical Sciences. All these patients had proven hepatitis C infection. Results: Out of 52 anti HCV positive samples, 28(53.84%) had genotype 1, 2 cases (3.88 %) had genotype 2 , 12 (23.08 %) had genotype 3 and 7 (13.4 %) had genotype 4 . Mixed infection with genotypes 1 and 3 was seen in 3 cases (5.77 %). Conclusion: TaqMan probes for detecting genotyping of HCV were successful in picking genotyping of HCV infection especially those with mixed genotypes. (author)

Comparison of nested-multiplex, Taqman & SYBR Green real-time PCR in diagnosis of amoebic liver abscess in a tertiary health care institute in India.

Science.gov (United States)

Dinoop, K P; Parija, Subhash Chandra; Mandal, Jharna; Swaminathan, R P; Narayanan, P

2016-01-01

Amoebiasis is a common parasitic infection caused by Entamoeba histolytica and amoebic liver abscess (ALA) is the most common extraintestinal manifestation of amoebiasis. The aim of this study was to standardise real-time PCR assays (Taqman and SYBR Green) to detect E. histolytica from liver abscess pus and stool samples and compare its results with nested-multiplex PCR. Liver abscess pus specimens were subjected to DNA extraction. The extracted DNA samples were subjected to amplification by nested-multiplex PCR, Taqman (18S rRNA) and SYBR Green real-time PCR (16S-like rRNA assays to detect E. histolytica/E. dispar/E. moshkovskii). The amplification products were further confirmed by DNA sequence analysis. Receiver operator characteristic (ROC) curve analysis was done for nested-multiplex and SYBR Green real-time PCR and the area under the curve was calculated for evaluating the accuracy of the tests to dignose ALA. In all, 17, 19 and 25 liver abscess samples were positive for E. histolytica by nested-multiplex PCR, SYBR Green and Taqman real-time PCR assays, respectively. Significant differences in detection of E. histolytica were noted in the real-time PCR assays evaluated ( Pnested-multiplex PCR, SYBR Green real-time PCR and Taqman real-time PCR evaluated showed a positivity rate of 34, 38 and 50 per cent, respectively. Based on ROC curve analysis (considering Taqman real-time PCR as the gold standard), it was observed that SYBR Green real-time PCR was better than conventional nested-multiplex PCR for the diagnosis of ALA. Taqman real-time PCR targeting the 18S rRNA had the highest positivity rate evaluated in this study. Both nested multiplex and SYBR Green real-time PCR assays utilized were evaluated to give accurate results. Real-time PCR assays can be used as the gold standard in rapid and reliable diagnosis, and appropriate management of amoebiasis, replacing the conventional molecular methods.

Towards Fluorescence In Vivo Hybridization (FIVH) Detection of H. pylori in Gastric Mucosa Using Advanced LNA Probes

Science.gov (United States)

Fontenete, Sílvia; Leite, Marina; Guimarães, Nuno; Madureira, Pedro; Ferreira, Rui Manuel; Figueiredo, Céu; Wengel, Jesper; Azevedo, Nuno Filipe

2015-01-01

In recent years, there have been several attempts to improve the diagnosis of infection caused by Helicobacter pylori. Fluorescence in situ hybridization (FISH) is a commonly used technique to detect H. pylori infection but it requires biopsies from the stomach. Thus, the development of an in vivo FISH-based method (FIVH) that directly detects and allows the visualization of the bacterium within the human body would significantly reduce the time of analysis, allowing the diagnosis to be performed during endoscopy. In a previous study we designed and synthesized a phosphorothioate locked nucleic acid (LNA)/ 2’ O-methyl RNA (2’OMe) probe using standard phosphoramidite chemistry and FISH hybridization was then successfully performed both on adhered and suspended bacteria at 37°C. In this work we simplified, shortened and adapted FISH to work at gastric pH values, meaning that the hybridization step now takes only 30 minutes and, in addition to the buffer, uses only urea and probe at non-toxic concentrations. Importantly, the sensitivity and specificity of the FISH method was maintained in the range of conditions tested, even at low stringency conditions (e.g., low pH). In conclusion, this methodology is a promising approach that might be used in vivo in the future in combination with a confocal laser endomicroscope for H. pylori visualization. PMID:25915865

Towards Fluorescence In Vivo Hybridization (FIVH Detection of H. pylori in Gastric Mucosa Using Advanced LNA Probes.

Directory of Open Access Journals (Sweden)

Sílvia Fontenete

Full Text Available In recent years, there have been several attempts to improve the diagnosis of infection caused by Helicobacter pylori. Fluorescence in situ hybridization (FISH is a commonly used technique to detect H. pylori infection but it requires biopsies from the stomach. Thus, the development of an in vivo FISH-based method (FIVH that directly detects and allows the visualization of the bacterium within the human body would significantly reduce the time of analysis, allowing the diagnosis to be performed during endoscopy. In a previous study we designed and synthesized a phosphorothioate locked nucleic acid (LNA/ 2' O-methyl RNA (2'OMe probe using standard phosphoramidite chemistry and FISH hybridization was then successfully performed both on adhered and suspended bacteria at 37°C. In this work we simplified, shortened and adapted FISH to work at gastric pH values, meaning that the hybridization step now takes only 30 minutes and, in addition to the buffer, uses only urea and probe at non-toxic concentrations. Importantly, the sensitivity and specificity of the FISH method was maintained in the range of conditions tested, even at low stringency conditions (e.g., low pH. In conclusion, this methodology is a promising approach that might be used in vivo in the future in combination with a confocal laser endomicroscope for H. pylori visualization.

Production of Conjugated Linoleic and Conjugated α-Linolenic Acid in a Reconstituted Skim Milk-Based Medium by Bifidobacterial Strains Isolated from Human Breast Milk

Directory of Open Access Journals (Sweden)

María Antonia Villar-Tajadura

2014-01-01

Full Text Available Eight bifidobacterial strains isolated from human breast milk have been tested for their abilities to convert linoleic acid (LA and α-linolenic acid (LNA to conjugated linoleic acid (CLA and conjugated α-linolenic acid (CLNA, respectively. These bioactive lipids display important properties that may contribute to the maintenance and improvement human health. Three selected Bifidobacterium breve strains produced CLA from LA and CLNA from LNA in MRS (160–170 and 210–230 μg mL−1, resp. and, also, in reconstituted skim milk (75–95 and 210–244 μg mL−1, resp.. These bifidobacterial strains were also able to simultaneously produce both CLA (90–105 μg mL−1 and CLNA (290–320 μg mL−1 in reconstituted skim milk. Globally, our findings suggest that these bifidobacterial strains are potential candidates for the design of new fermented dairy products naturally containing very high concentrations of these bioactive lipids. To our knowledge, this is the first study describing CLNA production and coproduction of CLA and CLNA by Bifidobacterium breve strains isolated from human milk in reconstituted skim milk.

Performance evaluation of the new Roche cobas AmpliPrep/cobas TaqMan HCV test, version 2.0, for detection and quantification of hepatitis C virus RNA

NARCIS (Netherlands)

S.D. Pas (Suzan); R. Molenkamp (Richard); J. Schinkel (Janke); S. Rebers; C. Copra (Cederick); S. Seven-Deniz; D. Thamke (Diana); R.J. de Knegt (Robert); B.L. Haagmans (Bart); M. Schutten (Martin)

2013-01-01

textabstractTo evaluate the analytical performance and explore the clinical applicability of the new Roche cobas AmpliPrep/cobas TaqMan HCV test, v2.0 (CAP/CTM v2.0), a platform comparison was performed on panels and diagnostic samples with the Roche cobas AmpliPrep/cobas TaqMan HCV test (CAP/CTM

Incorporation and fatty acid composition in liver of Nile tilapia fed with flaxseed oil - doi: 10.4025/actascitechnol.v33i2.7970

Directory of Open Access Journals (Sweden)

Polyana Batoqui França

2011-04-01

Full Text Available One of the most consumed freshwater fish in South America is Nile tilapia. The present study examined the effects of flaxseed oil (FO, source of alfa-linolenic acid (LNA, on the total lipid composition and polyunsaturated fatty acid, n-6 and n-3 PUFA, contents on Nile tilapia (Oreochromis niloticus liver. Tilapias were given diets with increasing levels 0.00, 1.2, 2.50, 3.75 and 5.00% (w w-1 of FO as a replacement of sunflower oil for five months. Fatty acids analysis of methyl esters revealed 45 fatty acids common to all treatments. The increase of flaxseed oil resulted in a decrease in total n-6 PUFA (35.1 to 21.1% and an increase in n-3 PUFA (3.3 to 18.5%. The diet with LNA underwent sequential desaturation and elongation in liver, leading to an increase in all n-3 PUFA and a decrease in n-6/n-3 ratios (10.7 to 1.1. The manipulation of fatty acids with FO may be used to increase n-3 PUFA and to help balance n-6/n-3 PUFA in dietary supplements, thus, the liver tilapia becomes one product with major nutritional value.

Specific and straightforward molecular investigation of β-thalassemia mutations in the Malaysian Malays and Chinese using direct TaqMan genotyping assays.

Science.gov (United States)

Kho, S L; Chua, K H; George, E; Tan, J A M A

2013-07-15

Beta-thalassemia is a life-threatening inherited blood disorder. Rapid characterization of β-globin gene mutations is necessary because of the high frequency of Malaysian β-thalassemia carriers. A combination real-time polymerase chain reaction genotyping assay using TaqMan probes was developed to confirm β-globin gene mutations. In this study, primers and probes were designed to specifically identify 8 common β-thalassemia mutations in the Malaysian Malay and Chinese ethnic groups using the Primer Express software. "Blind tests" using DNA samples from healthy individuals and β-thalassemia patients with different genotypes were performed to determine the specificity and sensitivity of this newly designed assay. Our results showed 100% sensitivity and specificity for this novel assay. In conclusion, the TaqMan genotyping assay is a straightforward assay that allows detection of β-globin gene mutations in less than 40 min. The simplicity and reproducibility of the TaqMan genotyping assay permit its use in laboratories as a rapid and cost-effective diagnostic tool for confirmation of common β-thalassemia mutations in Malaysia.

Evaluation of omega-3 fatty acids content and antioxidant activity in wheat (Triticum aestivum L. leaves Avaliação do teor de ácidos graxos ômega-3 e atividade antioxidante em folhas de trigo (Triticum aestivum L.

Directory of Open Access Journals (Sweden)

Ana Carolina de Aguiar

2011-08-01

Full Text Available The objective of this study was to quantify alpha-linolenic acid (LNA, 18:3n-3 of dried wheat leaves, harvested at different development stages (20, 40 and 80 days, to determine the antioxidant potential and the total phenolic compounds of leaves harvested at 80 days, as well as to perform mineral analysis (Na, K, Fe, Ca, Mg, P, Zn, Cu and Mn. It was observed a predominance of polyunsaturated fatty acids (PUFA compared to saturated fatty acids (SFA in the lipid fraction of leaves. Leaves collected in all periods presented ratios of PUFA/SFA, omega-6 and omega-3 fatty acids (n-6/n-3 considered suitable for food. The highest content of LNA was found in leaves harvested at 60 days, corresponding to 2.146,72 mg 100 g-1 dried matter. The range time between 60 and 80 days showed a decline of nearly 30% in the concentration of LNA. The acetate fraction was the most effective over DPPH radical assay, showing IC50 value of 154 µg mL-1, and the phenolic compounds content was 615.4 ± 36.4 mg EAG L-1, both analyses carried out in leaves harvested at 80 days. In this development stage, wheat leaves showed significant levels of the minerals P, Zn, Cu and Mn. These results reinforce the potential of using wheat leaves in foods, according to its antioxidant content and significant levels of LNA.Conduziu-se este estudo, com o objetivo de quantificar o ácido alfa-linolênico (LNA, 18:3n-3 em folhas de trigo secas e colhidas em diferentes estádios de desenvolvimento (20, 40 e 80 dias, determinar o potencial antioxidante e o conteúdo de fenólicos totais em folhas colhidas aos 80 dias, assim como realizar a analise de minerais (Na, K, Fe, Ca, Mg, P, Zn, Cu e Mn. Foi verificada uma predominância de ácidos graxos poli-insaturados (AGPI comparado com os ácidos graxos saturados (AGS na fração lipídica das folhas. As folhas colhidas em todos os períodos apresentaram razões de AGPI/AGS e de ácidos graxos ômega-6 e ômega-3 (n-6/n-3, dentro dos valores

miR-221 stimulates breast cancer cells and cancer-associated fibroblasts (CAFs) through selective interference with the A20/c-Rel/CTGF signaling.

Science.gov (United States)

Santolla, Maria Francesca; Lappano, Rosamaria; Cirillo, Francesca; Rigiracciolo, Damiano Cosimo; Sebastiani, Anna; Abonante, Sergio; Tassone, Pierfrancesco; Tagliaferri, Pierosandro; Di Martino, Maria Teresa; Maggiolini, Marcello; Vivacqua, Adele

2018-05-02

MicroRNA (miRNAs) are non-coding small RNA molecules that regulate gene expression by inhibiting the translation of target mRNAs. Among several dysregulated miRNAs in human cancer, the up-regulation of miR-221 has been associated with development of a variety of hematologic and solid malignancies. In this study, we investigated the involvement of miR-221 in breast cancer. TaqMan microRNA assay was used to detect the miR-221 levels in normal cells and in MDA-MB 231 and SkBr3 breast cancer cells as well as in main players of the tumor microenvironment, namely cancer-associated fibroblasts (CAFs). miR-221 mimic sequence and locked nucleic acid (LNA)-i-miR-221 construct were used to induce or inhibit, respectively, the miR-221 expression in cells used. Quantitative PCR and western blotting analysis were performed to evaluate the levels of the miR-221 target gene A20 (TNFAIP3), as well as the member of the NF-kB complex namely c-Rel and the connective tissue growth factor (CTGF). Chromatin immunoprecipitation (ChIP) assay was performed to ascertain the recruitment of c-Rel to the CTFG promoter. Finally, the cell growth and migration in the presence of LNA-i-miR-221 or silencing c-Rel and CTGF by specific short hairpin were assessed by cell count, colony formation and boyden chambers assays. Statistical analysis was performed by ANOVA. We first demonstrated that LNA-i-miR-221 inhibits both endogenous and ectopic expression of miR-221 in our experimental models. Next, we found that the A20 down-regulation, as well as the up-regulation of c-Rel induced by miR-221 were no longer evident using LNA-i-miR-221. Moreover, we established that the miR-221 dependent recruitment of c-Rel to the NF-kB binding site located within the CTGF promoter region is prevented by using LNA-i-miR-221. Furthermore, we determined that the up-regulation of CTGF mRNA and protein levels by miR-221 is no longer evident using LNA-i-miR221 and silencing c-Rel. Finally, we assessed that cell growth and

Comparison of real-time SYBR green dengue assay with real-time taqman RT-PCR dengue assay and the conventional nested PCR for diagnosis of primary and secondary dengue infection

Science.gov (United States)

Paudel, Damodar; Jarman, Richard; Limkittikul, Kriengsak; Klungthong, Chonticha; Chamnanchanunt, Supat; Nisalak, Ananda; Gibbons, Robert; Chokejindachai, Watcharee

2011-01-01

Background: Dengue fever and dengue hemorrhagic fever are caused by dengue virus. Dengue infection remains a burning problem of many countries. To diagnose acute dengue in the early phase we improve the low cost, rapid SYBR green real time assay and compared the sensitivity and specificity with real time Taqman® assay and conventional nested PCR assay. Aims: To develop low cost, rapid and reliable real time SYBR green diagnostic dengue assay and compare with Taqman real-time assay and conventional nested PCR (modified Lanciotti). Materials and Methods: Eight cultured virus strains were diluted in tenth dilution down to undetectable level by the PCR to optimize the primer, temperature (annealing, and extension and to detect the limit of detection of the assay. Hundred and ninety three ELISA and PCR proved dengue clinical samples were tested with real time SYBR® Green assay, real time Taqman® assay to compare the sensitivity and specificity. Results: Sensitivity and specificity of real time SYBR® green dengue assay (84% and 66%, respectively) was almost comparable to those (81% and 74%) of Taqman real time PCR dengue assay. Real time SYBR® green RT-PCR was equally sensitive in primary and secondary infection while real time Taqman was less sensitive in the secondary infection. Sensitivity of real time Taqman on DENV3 (87%) was equal to SYBR green real time PCR dengue assay. Conclusion: We developed low cost rapid diagnostic SYBR green dengue assay. Further study is needed to make duplex primer assay for the serotyping of dengue virus. PMID:22363089

Activity and Phylogenetic Diversity of Bacterial Cells with High and Low Nucleic Acid Content and Electron Transport System Activity in an Upwelling Ecosystem

OpenAIRE

Longnecker, K.; Sherr, B. F.; Sherr, E. B.

2005-01-01

We evaluated whether bacteria with higher cell-specific nucleic acid content (HNA) or an active electron transport system, i.e., positive for reduction of 5-cyano-2,3-ditolyl tetrazolium chloride (CTC), were responsible for the bulk of bacterioplankton metabolic activity. We also examined whether the phylogenetic diversity of HNA and CTC-positive cells differed from the diversity of Bacteria with low nucleic acid content (LNA). Bacterial assemblages were sampled both in eutrophic shelf waters...

The free energy of locking a ring: Changing a deoxyribonucleoside to a locked nucleic acid.

Science.gov (United States)

Xu, You; Villa, Alessandra; Nilsson, Lennart

2017-06-05

Locked nucleic acid (LNA), a modified nucleoside which contains a bridging group across the ribose ring, improves the stability of DNA/RNA duplexes significantly, and therefore is of interest in biotechnology and gene therapy applications. In this study, we investigate the free energy change between LNA and DNA nucleosides. The transformation requires the breaking of the bridging group across the ribose ring, a problematic transformation in free energy calculations. To address this, we have developed a 3-step (easy to implement) and a 1-step protocol (more efficient, but more complicated to setup), for single and dual topologies in classical molecular dynamics simulations, using the Bennett Acceptance Ratio method to calculate the free energy. We validate the approach on the solvation free energy difference for the nucleosides thymidine, cytosine, and 5-methyl-cytosine. © 2017 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. © 2017 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc.

Ultraselective electrochemiluminescence biosensor based on locked nucleic acid modified toehold-mediated strand displacement reaction and junction-probe.

Science.gov (United States)

Zhang, Xi; Zhang, Jing; Wu, Dongzhi; Liu, Zhijing; Cai, Shuxian; Chen, Mei; Zhao, Yanping; Li, Chunyan; Yang, Huanghao; Chen, Jinghua

2014-12-07

Locked nucleic acid (LNA) is applied in toehold-mediated strand displacement reaction (TMSDR) to develop a junction-probe electrochemiluminescence (ECL) biosensor for single-nucleotide polymorphism (SNP) detection in the BRCA1 gene related to breast cancer. More than 65-fold signal difference can be observed with perfectly matched target sequence to single-base mismatched sequence under the same conditions, indicating good selectivity of the ECL biosensor.

Measurement of Epstein-Barr virus DNA loads in whole blood and plasma by TaqMan PCR and in peripheral blood lymphocytes by competitive PCR.

Science.gov (United States)

Wadowsky, Robert M; Laus, Stella; Green, Michael; Webber, Steven A; Rowe, David

2003-11-01

Epstein-Barr virus (EBV) DNA load values were measured in samples of whole blood (n = 60) and plasma (n = 59) by TaqMan PCR and in samples of peripheral blood lymphocytes (PBLs) (n = 60) by competitive PCR (cPCR). The samples were obtained from 44 transplant recipients. The whole-blood and PBL loads correlated highly (r(2) > 0.900), whereas the plasma and PBL loads correlated poorly (r(2) = 0.512). Testing of whole blood by TaqMan PCR is an acceptable alternative to testing of PBLs by cPCR for quantifying EBV DNA load.

Lipid metabolic dose response to dietary alpha-linolenic acid in monk parrot (Myiopsitta monachus).

Science.gov (United States)

Petzinger, Christina; Heatley, J J; Bailey, Christopher A; Bauer, John E

2014-03-01

Monk parrots (Myiopsitta monachus) are susceptible to atherosclerosis, a progressive disease characterized by the formation of plaques in the arteries accompanied by underlying chronic inflammation. The family of n-3 fatty acids, especially eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA), have consistently been shown to reduce atherosclerotic risk factors in humans and other mammals. Some avian species have been observed to convert α-linolenic acid (18:3n-3, ALA) to EPA and DHA (Htin et al. in Arch Geflugelk 71:258-266, 2007; Petzinger et al. in J Anim Physiol Anim Nutr, 2013). Therefore, the metabolic effects of including flaxseed oil, as a source of ALA, in the diet at three different levels (low, medium, and high) on the lipid metabolism of Monk parrots was evaluated through measuring plasma total cholesterol (TC), free cholesterol (FC), triacylglycerols (TAG), and phospholipid fatty acids. Feed intake, body weight, and body condition score were also assessed. Thus the dose and possible saturation response of increasing dietary ALA at constant linoleic acid (18:2n-6, LNA) concentration on lipid metabolism in Monk parrots (M. monachus) was evaluated. Calculated esterified cholesterol in addition to plasma TC, FC, and TAG were unaltered by increasing dietary ALA. The high ALA group had elevated levels of plasma phospholipid ALA, EPA, and docosapentaenoic acid (DPAn-3, 22:5n-3). The medium and high ALA groups had suppressed plasma phospholipid 20:2n-6 and adrenic acid (22:4n-6, ADA) compared to the low ALA group. When the present data were combined with data from a previous study (Petzinger et al. in J Anim Physiol Anim Nutr, 2013) a dose response to dietary ALA was observed when LNA was constant. Plasma phospholipid ALA, EPA, DPAn-3, DHA, and total n-3 were positively correlated while 20:2n-6, di-homo-gamma-linoleic acid (20:3n-6Δ7), arachidonic acid (20:4n-6), ADA, and total n-6 were inversely correlated with dietary en% ALA.

Predictive efficacy of low burden EGFR mutation detected by next-generation sequencing on response to EGFR tyrosine kinase inhibitors in non-small-cell lung carcinoma.

Directory of Open Access Journals (Sweden)

Hye Sook Kim

Full Text Available Direct sequencing remains the most widely used method for the detection of epidermal growth factor receptor (EGFR mutations in lung cancer; however, its relatively low sensitivity limits its clinical use. The objective of this study was to investigate the sensitivity of detecting an epidermal growth factor receptor (EGFR mutation from peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR clamp and Ion Torrent Personal Genome Machine (PGM techniques compared to that by direct sequencing. Furthermore, the predictive efficacy of EGFR mutations detected by PNA-LNA PCR clamp was evaluated. EGFR mutational status was assessed by direct sequencing, PNA-LNA PCR clamp, and Ion Torrent PGM in 57 patients with non-small cell lung cancer (NSCLC. We evaluated the predictive efficacy of PNA-LNA PCR clamp on the EGFR-TKI treatment in 36 patients with advanced NSCLC retrospectively. Compared to direct sequencing (16/57, 28.1%, PNA-LNA PCR clamp (27/57, 47.4% and Ion Torrent PGM (26/57, 45.6% detected more EGFR mutations. EGFR mutant patients had significantly longer progressive free survival (14.31 vs. 21.61 months, P = 0.003 than that of EGFR wild patients when tested with PNA-LNA PCR clamp. However, no difference in response rate to EGFR TKIs (75.0% vs. 82.4%, P = 0.195 or overall survival (34.39 vs. 44.10 months, P = 0.422 was observed between the EGFR mutations by direct sequencing or PNA-LNA PCR clamp. Our results demonstrate firstly that patients with EGFR mutations were detected more frequently by PNA-LNA PCR clamp and Ion Torrent PGM than those by direct sequencing. EGFR mutations detected by PNA-LNA PCR clamp may be as a predicative factor for EGFR TKI response in patients with NSCLC.

Efficient reverse transcription using locked nucleic acid nucleotides towards the evolution of nuclease resistant RNA aptamers

DEFF Research Database (Denmark)

Crouzier, Lucile; Dubois, Camille; Edwards, Stacey L

2012-01-01

We found that SuperScript® III Reverse Transcriptase is an efficient enzyme for the recognition of LNA nucleotides, making it a prime candidate to be used in de novo selection of LNA containing RNA aptamers....

Experimental Warming Decreases the Average Size and Nucleic Acid Content of Marine Bacterial Communities

KAUST Repository

Huete-Stauffer, Tamara M.

2016-05-23

Organism size reduction with increasing temperature has been suggested as a universal response to global warming. Since genome size is usually correlated to cell size, reduction of genome size in unicells could be a parallel outcome of warming at ecological and evolutionary time scales. In this study, the short-term response of cell size and nucleic acid content of coastal marine prokaryotic communities to temperature was studied over a full annual cycle at a NE Atlantic temperate site. We used flow cytometry and experimental warming incubations, spanning a 6°C range, to analyze the hypothesized reduction with temperature in the size of the widespread flow cytometric bacterial groups of high and low nucleic acid content (HNA and LNA bacteria, respectively). Our results showed decreases in size in response to experimental warming, which were more marked in 0.8 μm pre-filtered treatment rather than in the whole community treatment, thus excluding the role of protistan grazers in our findings. Interestingly, a significant effect of temperature on reducing the average nucleic acid content (NAC) of prokaryotic cells in the communities was also observed. Cell size and nucleic acid decrease with temperature were correlated, showing a common mean decrease of 0.4% per °C. The usually larger HNA bacteria consistently showed a greater reduction in cell and NAC compared with their LNA counterparts, especially during the spring phytoplankton bloom period associated to maximum bacterial growth rates in response to nutrient availability. Our results show that the already smallest planktonic microbes, yet with key roles in global biogeochemical cycling, are likely undergoing important structural shrinkage in response to rising temperatures.

Experimental Warming Decreases the Average Size and Nucleic Acid Content of Marine Bacterial Communities

KAUST Repository

Huete-Stauffer, Tamara M.; Arandia-Gorostidi, Nestor; Alonso-Sá ez, Laura; Moran, Xose Anxelu G.

2016-01-01

Organism size reduction with increasing temperature has been suggested as a universal response to global warming. Since genome size is usually correlated to cell size, reduction of genome size in unicells could be a parallel outcome of warming at ecological and evolutionary time scales. In this study, the short-term response of cell size and nucleic acid content of coastal marine prokaryotic communities to temperature was studied over a full annual cycle at a NE Atlantic temperate site. We used flow cytometry and experimental warming incubations, spanning a 6°C range, to analyze the hypothesized reduction with temperature in the size of the widespread flow cytometric bacterial groups of high and low nucleic acid content (HNA and LNA bacteria, respectively). Our results showed decreases in size in response to experimental warming, which were more marked in 0.8 μm pre-filtered treatment rather than in the whole community treatment, thus excluding the role of protistan grazers in our findings. Interestingly, a significant effect of temperature on reducing the average nucleic acid content (NAC) of prokaryotic cells in the communities was also observed. Cell size and nucleic acid decrease with temperature were correlated, showing a common mean decrease of 0.4% per °C. The usually larger HNA bacteria consistently showed a greater reduction in cell and NAC compared with their LNA counterparts, especially during the spring phytoplankton bloom period associated to maximum bacterial growth rates in response to nutrient availability. Our results show that the already smallest planktonic microbes, yet with key roles in global biogeochemical cycling, are likely undergoing important structural shrinkage in response to rising temperatures.

A 0.18 μm CMOS inductorless complementary-noise-canceling-LNA for TV tuner applications

International Nuclear Information System (INIS)

Yuan Haiquan; Lin Fujiang; Fu Zhongqian; Huang Lu

2010-01-01

This paper presents an inductorless complementary-noise-canceling LNA (CNCLNA) for TV tuners. The CNCLNA exploits single-to-differential topology, which consists of a common gate stage and a common source stage. The complementary topology can save power and improve the noise figure. Linearity is also enhanced by employing a multiple gated transistors technique. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed CNCLNA achieves 13.5-16 dB voltage gain from 50 to 860 MHz, the noise figure is below 4.5 dB and has a minimum value of 2.9 dB, and the best P 1dB is -7.5 dBm at 860 MHz. The core consumes 6 mA current with a supply voltage of 1.8 V, while the core area is only 0.2 x 0.2 mm 2 . (semiconductor integrated circuits)

Identification and quantification of genetically modified Moonshade carnation lines using conventional and TaqMan real-time polymerase chain reaction methods.

Science.gov (United States)

Li, Peng; Jia, Junwei; Bai, Lan; Pan, Aihu; Tang, Xueming

2013-07-01

Genetically modified carnation (Dianthus caryophyllus L.) Moonshade was approved for planting and commercialization in several countries from 2004. Developing methods for analyzing Moonshade is necessary for implementing genetically modified organism labeling regulations. In this study, the 5'-transgene integration sequence was isolated using thermal asymmetric interlaced (TAIL)-PCR. Based upon the 5'-transgene integration sequence, conventional and TaqMan real-time PCR assays were established. The relative limit of detection for the conventional PCR assay was 0.05 % for Moonshade using 100 ng total carnation genomic DNA, corresponding to approximately 79 copies of the carnation haploid genome, and the limits of detection and quantification of the TaqMan real-time PCR assay were estimated to be 51 and 254 copies of haploid carnation genomic DNA, respectively. These results are useful for identifying and quantifying Moonshade and its derivatives.

Novel (Phenylethynyl)pyrene-LNA Constructs for Fluorescence SNP Sensing in Polymorphic Nucleic Acid Targets

DEFF Research Database (Denmark)

Astakhova, Irina Kira; Samokhina, Evgeniya; Babu, B Ravindra

2012-01-01

We describe fluorescent oligonucleotide probes labeled with novel (phenylethynyl)pyrene dyes attached to locked nucleic acids. Furthermore, we prove the utility of these probes for the effective detection of single-nucleotide polymorphisms in natural nucleic acids. High-affinity hybridization......DNA and RNA gene fragments. Target sequences were obtained by analysis of 200 clinical samples from patients currently receiving anti-HIV/AIDS combination therapy at the Russian Federal AIDS Center. Using these fluorescent oligonucleotides, we were able to detect the target mutation despite all the challenges...

Fluorescent oligonucleotides containing a novel perylene 2′-amino-α-L-LNA monomer: Synthesis and analytical potential

DEFF Research Database (Denmark)

Astakhova, Irina; Kumar, Santhosh T.; Wengel, Jesper

2011-01-01

efficiency of the resulting perylene-2'-amino-alpha-L-LNA monomer (T*) into synthetic oligonucleotides was significantly improved by replacement of the typically used 1H-tetrazole activator with pyridine hydrochloride. Generally, oligonucleotides containing monomer T* showed high binding affinity towards...... incorporations of monomers T* was quenched (quantum yield Phi(F) = 0.21) relative to duplexes of this probe with complementary DNA and RNA (Phi(F) = 0.42 and 0.35, respectively). On the contrary, a strong fluorescence quenching upon target binding was demonstrated by two short oligonucleotides of analogues...... sequences containing monomers T* at 5'- and 3'-terminal positions. We explain the hybridization-induced light-up effect observed for double-labeled probe by a reduction of fluorescence quenching due to precise positioning of the fluorophores within the double-stranded complexes. Furthermore, we propose...

TaqMan MGB probe fluorescence real-time quantitative PCR for rapid detection of Chinese Sacbrood virus.

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Ma Mingxiao

Full Text Available Sacbrood virus (SBV is a picorna-like virus that affects honey bees (Apis mellifera and results in the death of the larvae. Several procedures are available to detect Chinese SBV (CSBV in clinical samples, but not to estimate the level of CSBV infection. The aim of this study was develop an assay for rapid detection and quantification of this virus. Primers and probes were designed that were specific for CSBV structural protein genes. A TaqMan minor groove binder (MGB probe-based, fluorescence real-time quantitative PCR was established. The specificity, sensitivity and stability of the assay were assessed; specificity was high and there were no cross-reactivity with healthy larvae or other bee viruses. The assay was applied to detect CSBV in 37 clinical samples and its efficiency was compared with clinical diagnosis, electron microscopy observation, and conventional RT-PCR. The TaqMan MGB-based probe fluorescence real-time quantitative PCR for CSBV was more sensitive than other methods tested. This assay was a reliable, fast, and sensitive method that was used successfully to detect CSBV in clinical samples. The technology can provide a useful tool for rapid detection of CSBV. This study has established a useful protocol for CSBV testing, epidemiological investigation, and development of animal models.

Short locked nucleic acid antisense oligonucleotides potently reduce apolipoprotein B mRNA and serum cholesterol in mice and non-human primates

DEFF Research Database (Denmark)

Straarup, Ellen Marie; Fisker, Niels; Hedtjärn, Maj

2010-01-01

-life as longer oligonucleotides. Pharmacology studies in both mice and non-human primates were conducted with a 13-mer LNA oligonucleotide against apoB, and the data showed that repeated dosing of the 13-mer at 1-2 mg/kg/week was sufficient to provide a significant and long lasting lowering of non...... using the LNA chemistry. Conclusively, we present a 13-mer LNA oligonucleotide with therapeutic potential that produce beneficial cholesterol lowering effect in non-human primates....

Effects of Oils Rich in Linoleic and α-Linolenic Acids on Fatty Acid Profile and Gene Expression in Goat Meat

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Mahdi Ebrahimi

2014-09-01

Full Text Available Alteration of the lipid content and fatty acid (FA composition of foods can result in a healthier product. The aim of this study was to determine the effect of flaxseed oil or sunflower oil in the goat diet on fatty acid composition of muscle and expression of lipogenic genes in the semitendinosus (ST muscle. Twenty-one entire male Boer kid goats were fed diets containing different levels of linoleic acid (LA and α-linolenic acid (LNA for 100 days. Inclusion of flaxseed oil increased (p < 0.05 the α-linolenic acid (C18:3n-3 concentration in the ST muscle. The diet high in α-linolenic acid (p < 0.05 decreased the arachidonic acid (C20:4n-6 and conjugated linolenic acid (CLA c-9 t-11 content in the ST muscle. There was a significant (p < 0.05 upregulation of PPARα and PPARγ gene expression and downregulation of stearoyl-CoA desaturase (SCD gene in the ST muscle for the high α-linolenic acid group compared with the low α-linolenic acid group. The results of the present study show that flaxseed oil as a source of α-linolenic acid can be incorporated into the diets of goats to enrich goat meat with n-3 fatty acids, upregulate the PPARα and PPARγ, and downregulate the SCD gene expression.

Development of SYBR Green and TaqMan quantitative real-time PCR assays for hepatopancreatic parvovirus (HPV) infecting Penaeus monodon in India.

Science.gov (United States)

Yadav, Reena; Paria, Anutosh; Mankame, Smruti; Makesh, M; Chaudhari, Aparna; Rajendran, K V

2015-12-01

Hepatopancreatic parvovirus (HPV) infects Penaeus monodon and causes mortality in the larval stages. Further, it has been implicated in the growth retardation in cultured P. monodon. Though different geographical isolates of HPV show large sequence variations, a sensitive PCR assay specific to Indian isolate has not yet been reported. Here, we developed a sensitive SYBR Green-based and TaqMan real-time PCR for the detection and quantification of the virus. A 441-bp PCR amplicon was cloned in pTZ57 R/T vector and the plasmid copy number was estimated. A 10-fold serial dilution of the plasmid DNA from 1 × 10(9) copies to 1 copy was prepared and used as the standard. The primers were tested initially using the standard on a conventional PCR format to determine the linearity of detection. The standards were further tested on real-time PCR format using SYBR Green and TaqMan chemistry and standard curves were generated based on the Ct values from three well replicates for each dilution. The assays were found to be sensitive, specific and reproducible with a wide dynamic range (1 × 10(9) to 10 copies) with coefficient of regression (R(2)) > 0.99, calculated average slope -3.196 for SYBR Green assay whereas, for TaqMan assay it was >0.99 and -3.367, respectively. The intra- and inter-assay variance of the Ct values ranged from 0.26% to 0.94% and 0.12% to 0.81%, respectively, for SYBR Green assay, and the inter-assay variance of the Ct values for TaqMan assay ranged from 0.07% to 1.93%. The specificity of the assays was proved by testing other DNA viruses of shrimp such as WSSV, IHHNV and MBV. Standardized assays were further tested to detect and quantify HPV in the post-larvae of P. monodon. The result was further compared with conventional PCR to test the reproducibility of the test. The assay was also used to screen Litopeneaus vannamei, Macrobrachium rosenbergii and Scylla serrata for HPV. Copyright © 2015 Elsevier Ltd. All rights reserved.

TaqMan probe real-time polymerase chain reaction assay for the quantification of canine DNA in chicken nugget.

Science.gov (United States)

Rahman, Md Mahfujur; Hamid, Sharifah Bee Abd; Basirun, Wan Jefrey; Bhassu, Subha; Rashid, Nur Raifana Abdul; Mustafa, Shuhaimi; Mohd Desa, Mohd Nasir; Ali, Md Eaqub

2016-01-01

This paper describes a short-amplicon-based TaqMan probe quantitative real-time PCR (qPCR) assay for the quantitative detection of canine meat in chicken nuggets, which are very popular across the world, including Malaysia. The assay targeted a 100-bp fragment of canine cytb gene using a canine-specific primer and TaqMan probe. Specificity against 10 different animals and plants species demonstrated threshold cycles (Ct) of 16.13 ± 0.12 to 16.25 ± 0.23 for canine DNA and negative results for the others in a 40-cycle reaction. The assay was tested for the quantification of up to 0.01% canine meat in deliberately spiked chicken nuggets with 99.7% PCR efficiency and 0.995 correlation coefficient. The analysis of the actual and qPCR predicted values showed a high recovery rate (from 87% ± 28% to 112% ± 19%) with a linear regression close to unity (R(2) = 0.999). Finally, samples of three halal-branded commercial chicken nuggets collected from different Malaysian outlets were screened for canine meat, but no contamination was demonstrated.

Use of a Real-Time PCR TaqMan Assay for Rapid Identification and Differentiation of Burkholderia pseudomallei and Burkholderia mallei

OpenAIRE

U'Ren, Jana M.; Van Ert, Matthew N.; Schupp, James M.; Easterday, W. Ryan; Simonson, Tatum S.; Okinaka, Richard T.; Pearson, Talima; Keim, Paul

2005-01-01

A TaqMan allelic-discrimination assay designed around a synonymous single-nucleotide polymorphism was used to genotype Burkholderia pseudomallei and Burkholderia mallei isolates. The assay rapidly identifies and discriminates between these two highly pathogenic bacteria and does not cross-react with genetic near neighbors, such as Burkholderia thailandensis and Burkholderia cepacia.

A TaqMan Real-Time PCR Assay for Detection and Quantification of Sporisorium scitamineum in Sugarcane

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Yachun Su

2013-01-01

Full Text Available Sporisorium scitamineum is a fungal smut pathogen epidemic in sugarcane producing areas. Early detection and proper identification of the smut are an essential requirement in its management practice. In this study, we developed a TaqMan real-time PCR assay using specific primers (bEQ-F/bEQ-R and a TaqMan probe (bEQ-P which were designed based on the bE (b East mating type gene (Genbank Accession no. U61290.1. This method was more sensitive (a detection limit of 10 ag pbE DNA and 0.8 ng sugarcane genomic DNA than that of conventional PCR (10 fg and 100 ng, resp.. Reliability was demonstrated through the positive detection of samples collected from artificially inoculated sugarcane plantlets (FN40. This assay was capable of detecting the smut pathogen at the initial stage (12 h of infection and suitable for inspection of sugarcane pathogen-free seed cane and seedlings. Furthermore, quantification of pathogen was verified in pathogen-challenged buds in different sugarcane genotypes, which suggested its feasibility for evaluation of smut resistance in different sugarcane genotypes. Taken together, this novel assay can be used as a diagnostic tool for sensitive, accurate, fast, and quantitative detection of the smut pathogen especially for asymptomatic seed cane or plants and evaluation of smut resistance of sugarcane genotypes.

Multiplex preamplification of specific cDNA targets prior to gene expression analysis by TaqMan Arrays

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Ribal María

2008-06-01

Full Text Available Abstract Background An accurate gene expression quantification using TaqMan Arrays (TA could be limited by the low RNA quantity obtained from some clinical samples. The novel cDNA preamplification system, the TaqMan PreAmp Master Mix kit (TPAMMK, enables a multiplex preamplification of cDNA targets and therefore, could provide a sufficient amount of specific amplicons for their posterior analysis on TA. Findings A multiplex preamplification of 47 genes was performed in 22 samples prior to their analysis by TA, and relative gene expression levels of non-preamplified (NPA and preamplified (PA samples were compared. Overall, the mean cycle threshold (CT decrement in the PA genes was 3.85 (ranging from 2.07 to 5.01. A high correlation (r between the gene expression measurements of NPA and PA samples was found (mean r = 0.970, ranging from 0.937 to 0.994; p Conclusion We demonstrate that cDNA preamplification using the TPAMMK before TA analysis is a reliable approach to simultaneously measure gene expression of multiple targets in a single sample. Moreover, this procedure was validated in genes from degraded RNA samples and low abundance expressed genes. This combined methodology could have wide applications in clinical research, where scarce amounts of degraded RNA are usually obtained and several genes need to be quantified in each sample.

Detection of single-nucleotide polymorphisms using an ON-OFF switching of regenerated biosensor based on a locked nucleic acid-integrated and toehold-mediated strand displacement reaction.

Science.gov (United States)

Gao, Zhong Feng; Ling, Yu; Lu, Lu; Chen, Ning Yu; Luo, Hong Qun; Li, Nian Bing

2014-03-04

Although various strategies have been reported for single-nucleotide polymorphisms (SNPs) detection, development of a time-saving, specific, and regenerated electrochemical sensing platform still remains a realistic goal. In this study, an ON-OFF switching of a regenerated biosensor based on a locked nucleic acid (LNA)-integrated and toehold-mediated strand displacement reaction technique is constructed for detection of SNPs. The LNA-integrated and methylene blue-labeled capture probe with an external toehold is designed to switch on the sensing system. The mutant-type DNA probe completes complementary with the capture probe to trigger the strand displacement reaction, which switches off the sensing system. However, when the single-base mismatched wild-type DNA probe is presented, the strand displacement reaction cannot be achieved; therefore, the sensing system still keeps the ON state. This DNA sensor is stable over five reuses. We further testify that the LNA-integrated sequence has better recognition ability for SNPs detection compared to the DNA-integrated sequence. Moreover, this DNA senor exhibits a remarkable discrimination capability of SNPs among abundant wild-type targets and 6000-fold (m/m) excess of genomic DNA. In addition, it is selective enough in complex and contaminant-ridden samples, such as human urine, soil, saliva, and beer. Overall, these results demonstrate that this reliable DNA sensor is easy to be fabricated, simple to operate, and stable enough to be readily regenerated.

A Laboratory-Developed TaqMan Array Card for Simultaneous Detection of 19 Enteropathogens

Science.gov (United States)

Liu, Jie; Gratz, Jean; Amour, Caroline; Kibiki, Gibson; Becker, Stephen; Janaki, Lalitha; Verweij, Jaco J.; Taniuchi, Mami; Sobuz, Shihab U.; Haque, Rashidul; Haverstick, Doris M.

2013-01-01

The TaqMan Array Card (TAC) system is a 384-well singleplex real-time PCR format that has been used to detect multiple infection targets. Here we developed an enteric TaqMan Array Card to detect 19 enteropathogens, including viruses (adenovirus, astrovirus, norovirus GII, rotavirus, and sapovirus), bacteria (Campylobacter jejuni/C. coli, Clostridium difficile, Salmonella, Vibrio cholerae, diarrheagenic Escherichia coli strains including enteroaggregative E. coli [EAEC], enterotoxigenic E. coli [ETEC], enteropathogenic E. coli [EPEC], and Shiga-toxigenic E. coli [STEC]), Shigella/enteroinvasive E. coli (EIEC), protozoa (Cryptosporidium, Giardia lamblia, and Entamoeba histolytica), and helminths (Ascaris lumbricoides and Trichuris trichiura), as well as two extrinsic controls to monitor extraction and amplification efficiency (the bacteriophage MS2 and phocine herpesvirus). Primers and probes were newly designed or adapted from published sources and spotted onto microfluidic cards. Fecal samples were spiked with extrinsic controls, and DNA and RNA were extracted using the QiaAmp Stool DNA minikit and the QuickGene RNA Tissue kit, respectively, and then mixed with Ag-Path-ID One Step real-time reverse transcription-PCR (RT-PCR) reagents and loaded into cards. PCR efficiencies were between 90% and 105%, with linearities of 0.988 to 1. The limit of detection of the assays in the TAC was within a 10-fold difference from the cognate assays performed on plates. Precision testing demonstrated a coefficient of variation of below 5% within a run and 14% between runs. Accuracy was evaluated for 109 selected clinical specimens and revealed an average sensitivity and specificity of 85% and 77%, respectively, compared with conventional methods (including microscopy, culture, and immunoassay) and 98% and 96%, respectively, compared with our laboratory-developed PCR-Luminex assays. This TAC allows fast, accurate, and quantitative detection of a broad spectrum of enteropathogens and

Bat white-nose syndrome: a real-time TaqMan polymerase chain reaction test targeting the intergenic spacer region of Geomyces destructanstructans.

Science.gov (United States)

Muller, Laura K.; Lorch, Jeffrey M.; Lindner, Daniel L.; O'Connor, Michael; Gargas, Andrea; Blehert, David S.

2013-01-01

The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The test is highly sensitive, consistently detecting as little as 3.3 fg of genomic DNA from G. destructans. The real-time PCR test specifically amplified genomic DNA from G. destructans but did not amplify target sequence from 54 closely related fungal isolates (including 43 Geomyces spp. isolates) associated with bats. The test was further qualified by analyzing DNA extracted from 91 bat wing skin samples, and PCR results matched histopathology findings. These data indicate the real-time TaqMan PCR method described herein is a sensitive, specific, and rapid test to detect DNA from G. destructans and provides a valuable tool for WNS diagnostics and research.

Bioassay-guided supercritical fluid extraction of cyclooxygenase-2 inhibiting substances in Plantago major L.

Science.gov (United States)

Stenholm, A; Göransson, U; Bohlin, L

2013-02-01

Selective extraction of plant materials is advantageous for obtaining extracts enriched with desired constituents, thereby reducing the need for subsequent chromatography purification. Such compounds include three cyclooxygenase-2 (COX-2) inhibitory substances in Plantago major L. targeted in this investigation: α-linolenic acid (α-LNA) (18:3 ω-3) and the triterpenic acids ursolic acid and oleanolic acid. To investigate the scope for tuning the selectivity of supercritical fluid extraction (SFE) using bioassay guidance, and Soxhlet extraction with dichloromethane as solvent as a reference technique, to optimise yields of these substances. Extraction parameters were varied to optimise extracts' COX-2/COX-1 inhibitory effect ratios. The crude extracts were purified initially using a solid phase extraction (SPE) clean-up procedure and the target compounds were identified with GC-MS, LC-ESI-MS and LC-ESI-MS² using GC-FID for quantification. α-LNA was preferentially extracted in dynamic mode using unmodified carbon dioxide at 40°C and 172 bar, at a 0.04% (w/w) yield with a COX-2/COX-1 inhibitory effect ratio of 1.5. Ursolic and oleanolic acids were dynamically extracted at 0.25% and 0.06% yields, respectively, with no traces of (α-LNA) and a COX-2/COX-1-inhibitory effect ratio of 1.1 using 10% (v/v) ethanol as polar modifier at 75°C and 483 bar. The Soxhlet extracts had ursolic acid, oleanolic acid and αLNA yields up to 1.36%, 0.34% and 0.15%, respectively, with a COX-2/COX-1 inhibitory effect ratio of 1.2. The target substances can be extracted selectively by bioassay guided optimisation of SFE conditions. Copyright © 2012 John Wiley & Sons, Ltd.

Detection and Quantification of Methyl tert-Butyl Ether-Degrading Strain PM1 by Real-Time TaqMan PCR

OpenAIRE

Hristova, Krassimira R.; Lutenegger, Christian M.; Scow, Kate M.

2001-01-01

The fuel oxygenate methyl tert-butyl ether (MTBE), a widely distributed groundwater contaminant, shows potential for treatment by in situ bioremediation. The bacterial strain PM1 rapidly mineralizes and grows on MTBE in laboratory cultures and can degrade the contaminant when inoculated into groundwater or soil microcosms. We applied the TaqMan quantitative PCR method to detect and quantify strain PM1 in laboratory and field samples. Specific primers and probes were designed for the 16S ribos...

Sphingosine kinase 1 is a relevant molecular target in gastric cancer

DEFF Research Database (Denmark)

Fuereder, Thorsten; Hoeflmayer, Doris; Jaeger-Lansky, Agnes

2011-01-01

Sphingosine kinase 1 (Sphk1), a lipid kinase implicated in cell transformation and tumor growth, is overexpressed in gastric cancer and is linked with a poor prognosis. The biological relevance of Sphk1 expression in gastric cancer is unclear. Here, we studied the functional significance of Sphk1...... as a novel molecular target for gastric cancer by using an antisense oligonucleotide approach in vitro and in vivo. Gastric cancer cell lines (MKN28 and N87) were treated with Sphk1 with locked nucleic acid-antisense oligonucleotides (LNA-ASO). Sphk1 target regulation, cell growth, and apoptosis were...... assessed for single-agent Sphk1 LNA-ASO and for combinations with doxorubicin. Athymic nude mice xenografted with gastric cancer cells were treated with Sphk1 LNA and assessed for tumor growth and Sphk1 target regulation, in vivo. In vitro, nanomolar concentrations of Sphk1 LNA-ASO induced an approximately...

Bat white-nose syndrome: A real-time TaqMan polymerase chain reaction test targeting the intergenic spacer region of Geomyces destructans

Science.gov (United States)

Laura K Muller; Jeffrey M. Lorch; Daniel L. Lindner; Michael O' Connor; Andrea Gargas; David S. Blehert

2013-01-01

The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The...

Performance evaluation of the Cobas TaqMan MTB assay on respiratory specimens according to clinical application

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Jong Eun Park

2017-11-01

Full Text Available Objective: To evaluate the performance of the Cobas TaqMan MTB assay (Cobas assay with respect to its clinical application. Methods: This was a retrospective analysis of 1154 results from 1034 patients for whom mycobacterial cultures and the Cobas assay were performed simultaneously. Based on the patient medical records, two categories of clinical application were defined: (1 the diagnosis of patients with a high probability of pulmonary tuberculosis according to clinical and radiological features (n = 128, and (2 the exclusion of tuberculosis in clinically indeterminate patients (n = 1026. Standard culture was used as the reference method. Results: The sensitivity of the Cobas assay for the detection of Mycobacterium tuberculosis was 70.4% (95% confidence interval (CI 49.7–85.5% for category 1, but only 25.0% (95% CI 4.5–64.4% for category 2. The specificity was ≥95.0% for both categories. The positive predictive value was 79.2% (95% CI 57.3–92.1% for category 1 and 33.3% (95% CI 6.0–75.9% for category 2, while the negative predictive value was 92.3% (95% CI 85.0–96.4% for category 1 and 99.4% (95% CI 98.7–99.8% for category 2. Conclusions: The results of this study indicate that Cobas assay results must be interpreted carefully according to the clinical purpose of the assay. Keywords: Mycobacterium tuberculosis, Pulmonary tuberculosis, Cobas TaqMan MTB assay, Korea

Rapid identification of tomato Sw-5 resistance-breaking isolates of Tomato spotted wilt virus using high resolution melting and TaqMan SNP Genotyping assays as allelic discrimination techniques.

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Valentina di Rienzo

Full Text Available In tomato, resistance to Tomato spotted wilt virus (TSWV is conferred by the dominant gene, designated Sw-5. Virulent Sw-5 resistance breaking (SRB mutants of TSWV have been reported on Sw-5 tomato cultivars. Two different PCR-based allelic discrimination techniques, namely Custom TaqMan™ SNP Genotyping and high-resolution melting (HRM assays, were developed and compared for their ability to distinguish between avirulent (Sw-5 non-infecting, SNI and SRB biotypes. TaqMan assays proved to be more sensitive (threshold of detection in a range of 50-70 TSWV RNA copies and more reliable than HRM, assigning 25 TSWV isolates to their correct genotype with an accuracy of 100%. Moreover, the TaqMan SNP assays were further improved developing a rapid and simple protocol that included crude leaf extraction for RNA template preparations. On the other hand, HRM assays showed higher levels of sensitivity than TaqMan when used to co-detect both biotypes in different artificial mixtures. These diagnostic assays contributed to gain preliminary information on the epidemiology of TSWV isolates in open field conditions. In fact, the presented data suggest that SRB isolates are present as stable populations established year round, persisting on both winter (globe artichoke and summer (tomato crops, in the same cultivated areas of Southern Italy.

Locked nucleoside analogues expand the potential of DNAzymes to cleave structured RNA targets

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Wengel Jesper

2006-06-01

Full Text Available Abstract Background DNAzymes cleave at predetermined sequences within RNA. A prerequisite for cleavage is that the DNAzyme can gain access to its target, and thus the DNAzyme must be capable of unfolding higher-order structures that are present in the RNA substrate. However, in many cases the RNA target sequence is hidden in a region that is too tightly structured to be accessed under physiological conditions by DNAzymes. Results We investigated how incorporation of LNA (locked nucleic acid monomers into DNAzymes improves their ability to gain access and cleave at highly-structured RNA targets. The binding arms of DNAzymes were varied in length and were substituted with up to three LNA and α-L-LNA monomers (forming LNAzymes. For one DNAzyme, the overall cleavage reaction proceeded fifty times faster after incorporation of two α-L-LNA monomers per binding arm (kobs increased from 0.014 min-1 to 0.78 min-1. Conclusion The data demonstrate how hydrolytic performance can be enhanced by design of LNAzymes, and indicate that there are optimal lengths for the binding arms and for the number of modified LNA monomers.

Apoptosis- and differentiation-inducing activities of jacaric acid, a conjugated linolenic acid isomer, on human eosinophilic leukemia EoL-1 cells.

Science.gov (United States)

Liu, Wai-Nam; Leung, Kwok-Nam

2014-11-01

Conjugated linolenic acids (CLNAs) are a group of naturally occurring positional and geometrical isomers of the C18 polyunsaturated essential fatty acid, linolenic acid (LNA), with three conjugated double bonds (C18:3). Although previous research has demonstrated the growth-inhibitory effects of CLNA on a wide variety of cancer cell lines in vitro, their action mechanisms and therapeutic potential on human myeloid leukemia cells remain poorly understood. In the present study, we found that jacaric acid (8Z,10E,12Z-octadecatrienoic acid), a CLNA isomer which is present in jacaranda seed oil, inhibited the in vitro growth of human eosinophilic leukemia EoL-1 cells in a time- and concentration-dependent manner. Mechanistic studies showed that jacaric acid triggered cell cycle arrest of EoL-1 cells at the G0/G1 phase and induced apoptosis of the EoL-1 cells, as measured by the Cell Death Detection ELISAPLUS kit, Annexin V assay and JC-1 dye staining. Notably, the jacaric acid-treated EoL-1 cells also underwent differentiation as revealed by morphological and phenotypic analysis. Collectively, our results demonstrated the capability of jacaric acid to inhibit the growth of EoL-1 cells in vitro through triggering cell cycle arrest and by inducing apoptosis and differentiation of the leukemia cells. Therefore, jacaric acid might be developed as a potential candidate for the treatment of certain forms of myeloid leukemia with minimal toxicity and few side effects.

Establishment of real time allele specific locked nucleic acid quantitative PCR for detection of HBV YIDD (ATT mutation and evaluation of its application.

Directory of Open Access Journals (Sweden)

Yongbin Zeng

Full Text Available BACKGROUND: Long-term use of nucleos(tide analogues can increase risk of HBV drug-resistance mutations. The rtM204I (ATT coding for isoleucine is one of the most important resistance mutation sites. Establishing a simple, rapid, reliable and highly sensitive assay to detect the resistant mutants as early as possible is of great clinical significance. METHODS: Recombinant plasmids for HBV YMDD (tyrosine-methionine-aspartate-aspartate and YIDD (tyrosine-isoleucine-aspartate-aspartate were constructed by TA cloning. Real time allele specific locked nucleic acid quantitative PCR (RT-AS-LNA-qPCR with SYBR Green I was established by LNA-modified primers and evaluated with standard recombinant plasmids, clinical templates (the clinical wild type and mutant HBV DNA mixture and 102 serum samples from nucleos(tide analogues-experienced patients. The serum samples from a chronic hepatitis B (CHB patient firstly received LMV mono therapy and then switched to LMV + ADV combined therapy were also dynamically analyzed for 10 times. RESULTS: The linear range of the assay was between 1×10(9 copies/μl and 1 × 10(2 copies/μl. The low detection limit was 1 × 10(1 copies/μl. Sensitivity of the assay were 10(-6, 10(-4 and 10(-2 in the wild-type background of 1 × 10(9 copies/μl, 1 × 10(7 copies/μl and 1 × 10(5 copies/μl, respectively. The sensitivity of the assay in detection of clinical samples was 0.03%. The complete coincidence rate between RT-AS-LNA-qPCR and direct sequencing was 91.2% (93/102, partial coincidence rate was 8.8% (9/102, and no complete discordance was observed. The two assays showed a high concordance (Kappa = 0.676, P = 0.000. Minor variants can be detected 18 weeks earlier than the rebound of HBV DNA load and alanine aminotransferase level. CONCLUSIONS: A rapid, cost-effective, high sensitive, specific and reliable method of RT-AS-LNA-qPCR with SYBR Green I for early and absolute quantification of HBV YIDD (ATT coding for isoleucine

A new general model for predicting melting thermodynamics of complementary and mismatched B-form duplexes containing locked nucleic acids: application to probe design for digital PCR detection of somatic mutations.

Science.gov (United States)

Hughesman, Curtis; Fakhfakh, Kareem; Bidshahri, Roza; Lund, H Louise; Haynes, Charles

2015-02-17

Advances in real-time polymerase chain reaction (PCR), as well as the emergence of digital PCR (dPCR) and useful modified nucleotide chemistries, including locked nucleic acids (LNAs), have created the potential to improve and expand clinical applications of PCR through their ability to better quantify and differentiate amplification products, but fully realizing this potential will require robust methods for designing dual-labeled hydrolysis probes and predicting their hybridization thermodynamics as a function of their sequence, chemistry, and template complementarity. We present here a nearest-neighbor thermodynamic model that accurately predicts the melting thermodynamics of a short oligonucleotide duplexed either to its perfect complement or to a template containing mismatched base pairs. The model may be applied to pure-DNA duplexes or to duplexes for which one strand contains any number and pattern of LNA substitutions. Perturbations to duplex stability arising from mismatched DNA:DNA or LNA:DNA base pairs are treated at the Gibbs energy level to maintain statistical significance in the regressed model parameters. This approach, when combined with the model's accounting of the temperature dependencies of the melting enthalpy and entropy, permits accurate prediction of T(m) values for pure-DNA homoduplexes or LNA-substituted heteroduplexes containing one or two independent mismatched base pairs. Terms accounting for changes in solution conditions and terminal addition of fluorescent dyes and quenchers are then introduced so that the model may be used to accurately predict and thereby tailor the T(m) of a pure-DNA or LNA-substituted hydrolysis probe when duplexed either to its perfect-match template or to a template harboring a noncomplementary base. The model, which builds on classic nearest-neighbor thermodynamics, should therefore be of use to clinicians and biologists who require probes that distinguish and quantify two closely related alleles in either a

Ruminal biohydrogenation kinetics of defatted flaxseed and sunflower is affected by heat treatment

DEFF Research Database (Denmark)

Lashkari, Saman; Hymøller, Lone; Jensen, Søren Krogh

2017-01-01

The effect of heat treatment on biohydrogenation of linoleic acid (LA) and linolenic acid (LNA) and formation of stearic acid (SA), cis-9, trans-11 conjugated LA (CLA), trans-10, cis-12 CLA and trans-vaccenic acid (VA) was studied in in vitro incubations with diluted rumen fluid as inoculum...

Development of bis-locked nucleic acid (bisLNA) oligonucleotides for efficient invasion of supercoiled duplex DNA

DEFF Research Database (Denmark)

Moreno, Pedro M D; Geny, Sylvain; Pabon, Y Vladimir

2013-01-01

In spite of the many developments in synthetic oligonucleotide (ON) chemistry and design, invasion into double-stranded DNA (DSI) under physiological salt and pH conditions remains a challenge. In this work, we provide a new ON tool based on locked nucleic acids (LNAs), designed for strand invasi...

CYP2D7 sequence variation interferes with TaqMan CYP2D6*15 and *35 genotyping

Directory of Open Access Journals (Sweden)

Amanda K Riffel

2016-01-01

Full Text Available TaqMan™ genotyping assays are widely used to genotype CYP2D6, which encodes a major drug metabolizing enzyme. Assay design for CYP2D6 can be challenging owing to the presence of two pseudogenes, CYP2D7 and CYP2D8, structural and copy number variation and numerous single nucleotide polymorphisms (SNPs some of which reflect the wild-type sequence of the CYP2D7 pseudogene. The aim of this study was to identify the mechanism causing false positive CYP2D6*15 calls and remediate those by redesigning and validating alternative TaqMan genotype assays. Among 13,866 DNA samples genotyped by the CompanionDx® lab on the OpenArray platform, 70 samples were identified as heterozygotes for 137Tins, the key SNP of CYP2D6*15. However, only 15 samples were confirmed when tested with the Luminex xTAG CYP2D6 Kit and sequencing of CYP2D6-specific long range (XL-PCR products. Genotype and gene resequencing of CYP2D6 and CYP2D7-specific XL-PCR products revealed a CC>GT dinucleotide SNP in exon 1 of CYP2D7 that reverts the sequence to CYP2D6 and allows a TaqMan assay PCR primer to bind. Because CYP2D7 also carries a Tins, a false-positive mutation signal is generated. This CYP2D7 SNP was also responsible for generating false-positive signals for rs769258 (CYP2D6*35 which is also located in exon 1. Although alternative CYP2D6*15 and *35 assays resolved the issue, we discovered a novel CYP2D6*15 subvariant in one sample that carries additional SNPs preventing detection with the alternate assay. The frequency of CYP2D6*15 was 0.1% in this ethnically diverse U.S. population sample. In addition, we also discovered linkage between the CYP2D7 CC>GT dinucleotide SNP and the 77G>A (rs28371696 SNP of CYP2D6*43. The frequency of this tentatively functional allele was 0.2%. Taken together, these findings emphasize that regardless of how careful genotyping assays are designed and evaluated before being commercially marketed, rare or unknown SNPs underneath primer and/or probe

Development of a real-time TaqMan assay to detect mendocina sublineage Pseudomonas species in contaminated metalworking fluids.

Science.gov (United States)

Saha, Ratul; Donofrio, Robert S; Bagley, Susan T

2010-08-01

A TaqMan quantitative real-time polymerase chain reaction (qPCR) assay was developed for the detection and enumeration of three Pseudomonas species belonging to the mendocina sublineage (P. oleovorans, P. pseudoalcaligenes, and P. oleovorans subsp. lubricantis) found in contaminated metalworking fluids (MWFs). These microbes are the primary colonizers and serve as indicator organisms of biodegradation of used MWFs. Molecular techniques such as qPCR are preferred for the detection of these microbes since they grow poorly on typical growth media such as R2A agar and Pseudomonas isolation agar (PIA). Traditional culturing techniques not only underestimate the actual distribution of these bacteria but are also time-consuming. The primer-probe pair developed from gyrase B (gyrB) sequences of the targeted bacteria was highly sensitive and specific for the three species. qPCR was performed with both whole cell and genomic DNA to confirm the specificity and sensitivity of the assay. The sensitivity of the assay was 10(1) colony forming units (CFU)/ml for whole cell and 13.7 fg with genomic DNA. The primer-probe pair was successful in determining concentrations from used MWF samples, indicating levels between 2.9 x 10(3) and 3.9 x 10(6) CFU/ml. In contrast, the total count of Pseudomonas sp. recovered on PIA was in the range of <1.0 x 10(1) to 1.4 x 10(5) CFU/ml for the same samples. Based on these results from the qPCR assay, the designed TaqMan primer-probe pair can be efficiently used for rapid (within 2 h) determination of the distribution of these species of Pseudomonas in contaminated MWFs.

Rapid detection of Enterovirus and Coxsackievirus A10 by a TaqMan based duplex one-step real time RT-PCR assay.

Science.gov (United States)

Chen, Jingfang; Zhang, Rusheng; Ou, Xinhua; Yao, Dong; Huang, Zheng; Li, Linzhi; Sun, Biancheng

2017-06-01

A TaqMan based duplex one-step real time RT-PCR (rRT-PCR) assay was developed for the rapid detection of Coxsackievirus A10 (CV-A10) and other enterovirus (EVs) in clinical samples. The assay was fully evaluated and found to be specific and sensitive. When applied in 115 clinical samples, a 100% diagnostic sensitivity in CV-A10 detection and 97.4% diagnostic sensitivity in other EVs were found. Copyright © 2017 Elsevier Ltd. All rights reserved.

Differences in sheep and goats milk fatty acid profile between conventional and organic farming systems.

Science.gov (United States)

Tsiplakou, Eleni; Kotrotsios, Vaios; Hadjigeorgiou, Ioannis; Zervas, George

2010-08-01

The objective of this study was to investigate whether there is a difference in chemical composition and particularly in fatty acid (FA) profile, with emphasis on cis-9, trans-11 CLA, of milk obtained from conventional and organic dairy sheep and goats farms under the farming conditions practiced in Greece. Four dairy sheep and four dairy goat farms, representing common conventional production systems and another four dairy sheep and four dairy goat farms, organically certified, representing organic production and feeding systems were selected from all over Greece. One hundred and sixty two individual milk samples were collected from those farms in January-February 2009, about three months after parturition. The milk samples were analyzed for their main chemical constituents and their FA profile. The results showed that the production system affected milk chemical composition: in particular fat content was lower in the organic sheep and goats milk compared with the corresponding conventional. Milk from organic sheep had higher content in MUFA, PUFA, alpha-LNA, cis-9, trans-11 CLA, and omega-3 FA, whereas in milk from organic goats alpha-LNA and omega-3 FA content was higher than that in conventional one. These differences are, mainly, attributed to different feeding practices used by the two production systems. The results of this study show that the organic milk produced under the farming conditions practiced in Greece has higher nutritional value, due to its FA profile, compared with the respective conventional milk.

Effects of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) on Fetal Pulmonary Circulation: An Experimental Study in Fetal Lambs.

Science.gov (United States)

Sharma, Dyuti; Aubry, Estelle; Ouk, Thavarak; Houeijeh, Ali; Houfflin-Debarge, Véronique; Besson, Rémi; Deruelle, Philippe; Storme, Laurent

2017-07-16

Background: Persistent pulmonary hypertension of the newborn (PPHN) causes significant morbidity and mortality in neonates. n -3 Poly-unsaturated fatty acids have vasodilatory properties in the perinatal lung. We studied the circulatory effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fetal sheep and in fetal pulmonary arterial rings. Methods: At 128 days of gestation, catheters were placed surgically in fetal systemic and pulmonary circulation, and a Doppler probe around the left pulmonary artery (LPA). Pulmonary arterial pressure and LPA flow were measured while infusing EPA or DHA for 120 min to the fetus, to compute pulmonary vascular resistance (PVR). The dose effects of EPA or DHA were studied in vascular rings pre-constricted with serotonin. Rings treated with EPA were separated into three groups: E+ (intact endothelium), E- (endothelium stripped) and LNA E+ (pretreatment of E+ rings with l-nitro-arginine). Results: EPA, but not DHA, induced a significant and prolonged 25% drop in PVR ( n = 8, p DHA resulted in only a mild relaxation at the highest concentration of DHA (300 µM) compared to E+. Conclusions: EPA induces a sustained pulmonary vasodilatation in fetal lambs. This effect is endothelium- and dose-dependent and involves nitric oxide (NO) production. We speculate that EPA supplementation may improve pulmonary circulation in clinical conditions with PPHN.

A TaqMan real-time PCR assay for detection of Meloidogyne hapla in root galls and in soil

DEFF Research Database (Denmark)

Sapkota, Rumakanta; Skantar, Andrea M.; Nicolaisen, Mogens

2016-01-01

. haplaand showed no significant amplification of DNA from non-target nematodes. The assay was able to detect M. haplain a background of plant and soil DNA. A dilution series of M. haplaeggs in soil showed a high correlation ( R 2 = 0 . 95 , P ...Early detection and quantification of Meloidogyne haplain soil is essential for effective disease management. The purpose of this study was to develop a real-time PCR assay for detection of M. haplain soil. Primers and a TaqMan probe were designed for M. hapladetection. The assay detected M......-knot development in carrots by testing soils before planting. The assay could be useful for management decisions in carrot cultivation....

A TaqMan real-time PCR-based assay for the identification of Fasciola spp.

Science.gov (United States)

Alasaad, Samer; Soriguer, Ramón C; Abu-Madi, Marawan; El Behairy, Ahmed; Jowers, Michael J; Baños, Pablo Díez; Píriz, Ana; Fickel, Joerns; Zhu, Xing-Quan

2011-06-30

Real time quantitative PCR (qPCR) is one of the key technologies of the post-genome era, with clear advantages compared to normal end-point PCR. In this paper, we report the first qPCR-based assay for the identification of Fasciola spp. Based on sequences of the second internal transcribed spacers (ITS-2) of the ribosomal rRNA gene, we used a set of genus-specific primers for Fasciola ITS-2 amplification, and we designed species-specific internal TaqMan probes to identify F. hepatica and F. gigantica, as well as the hybrid 'intermediate'Fasciola. These primers and probes were used for the highly specific, sensitive, and simple identification of Fasciola species collected from different animal host from China, Spain, Niger and Egypt. The novel qPCR-based technique for the identification of Fasciola spp. may provide a useful tool for the epidemiological investigation of Fasciola infection, including their intermediate snail hosts. Copyright © 2011 Elsevier B.V. All rights reserved.

A role for serotonin in the antidepressant activity of NG-Nitro-L-arginine, in the rat forced swimming test.

Science.gov (United States)

Gigliucci, Valentina; Buckley, Kathleen Niamh; Nunan, John; O'Shea, Karen; Harkin, Andrew

2010-02-01

The present study determined regional serotonin (5-HT) synthesis and metabolism changes associated with the nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine (L-NA) and the influence of 5-HT receptor blockade in the antidepressant-like actions of L-NA in the forced swimming test (FST). Regional effects of L-NA (5,10 and 20mg/kg i.p.) on tryptophan hydroxylase (TPH) activity, the rate limiting enzyme for 5-HT synthesis, were determined by measuring accumulation of the transient intermediate 5-hydoxytryptophan (5-HTP) following in vivo administration of the amino acid decarboxylase inhibitor, NSD 1015 (100mg/kg). L-NA (5-20mg/kg) dose dependently increased 5-HTP accumulation, particularly in the amygdaloid cortex, following exposure to the FST. L-NA also provoked an increase in regional brain 5-HIAA concentrations and in the 5-HIAA:5-HT metabolism ratio. Co-treatment with NSD-1015 failed to consistently modify the antidepressant-like effects of L-NA in the FST. Sub-active doses of L-NA (1mg/kg) and the 5-HT re-uptake inhibitor fluoxetine (2.5mg/kg) acted synergistically to increase swimming in the test. Co-treatment with the non-selective 5-HT receptor antagonist metergoline (1, 2 and 4mg/kg), attenuated the L-NA (20mg/kg)-induced reduction in immobility and increase in swimming behaviours. Metergoline alone however provoked an increase in immobility and reduction in swimming behaviours in the test. A similar response was obtained following co-treatment with the preferential 5-HT(2A) receptor antagonist ketanserin (5mg/kg) and the 5-HT(2C) receptor antagonist RO-430440 (5mg/kg). Co-treatment with the 5-HT(1A) receptor antagonist WAY 100635 (0.3mg/kg) or the 5-HT(1B) receptor antagonist GR 127935 (4mg/kg) failed to influence the antidepressant-like activity of L-NA. Taken together these data provide further support for a role for 5-HT in the antidepressant-like properties of NOS inhibitors. Copyright 2009 Elsevier Inc. All rights reserved.

LNA-modified isothermal oligonucleotide microarray for ...

Indian Academy of Sciences (India)

2014-10-20

Oct 20, 2014 ... the advent of DNA microarray techniques (Lee et al. 2007). ... atoms of ribose to form a bicyclic ribosyl structure. It is the .... 532 nm and emission at 570 nm. The signal ..... sis and validation using real-time PCR. Nucleic Acids ...

Effect of Native Gastric Mucus on in vivo Hybridization Therapies Directed at Helicobacter pylori

DEFF Research Database (Denmark)

Santos, Rita S; Dakwar, George R; Xiong, Ranhua

2015-01-01

Helicobacter pylori infects more than 50% of the worldwide population. It is mostly found deep in the gastric mucus lining of the stomach, being a major cause of peptic ulcers and gastric adenocarcinoma. To face the increasing resistance of H. pylori to antibiotics, antimicrobial nucleic acid...... barriers-the highly viscoelastic gastric mucus and the bacterial cell envelope. We found that LNA/2'OMe is capable of diffusing rapidly through native, undiluted, gastric mucus isolated from porcine stomachs, without degradation. Moreover, although LNA/2'OMe hybridization was still successful without...

Development and evaluation of novel one-step TaqMan realtime RT-PCR assays for the detection and direct genotyping of genogroup I and II noroviruses

DEFF Research Database (Denmark)

Schultz, Anna Charlotte; Vega, Everado; Dalsgaard, Anders

2011-01-01

BackgroundCurrent detection and genotyping methods of genogroup (G) I and II noroviruses (NoVs) consist of a 2-step approach including detection of viral RNA by TaqMan realtime RT-PCR (RT-qPCR) followed by conventional RT-PCR and sequencing of partial regions of ORF1 or ORF2. ObjectiveTo develop ......Man RT-qPCR assays for the sensitive detection and direct genotyping of GI and GII NoVs from clinical and environmental matrices...... novel long-template one-step TaqMan assays (L-RT-qPCR) for the rapid detection and direct genotyping of GI and GII NoVs and to evaluate the sensitivity and specificity of the assays. Study designGI and GII-specific broadly reactive L-RT-qPCR assays were developed by combining existing NoV primers...... and probes targeting the open reading frame (ORF)1–ORF2 junction as well as region C at the 5′–ORF2. The assays were validated using GI and GII RNA transcripts and a coded panel of 75 stool samples containing NoV strains representing 9 GI genotypes and 12 GII genotypes, as well as sapoviruses, astroviruses...

Quantum properties of spin polarized helium 3 optically oriented by a LNA laser

International Nuclear Information System (INIS)

Leduc, M.; Laloe, F.; Nacher, P.J.; Tastevin, G.; Daniels, J.M.; Betts, D.

1986-01-01

Spin polarized helium 3 (/sup 3/He increasing) and also atomic hydrogen (H decreasing) are systems exhibiting a number of unusual and interesting properties at low temperature. This is true even for dilute polarized gases in spite of the weakness of the nuclear magnetic interaction between atoms. The changes in the macroscopic properties of the gas with the nuclear polarization P are pure consequences of the indistinguishability of the particles and of the symmetrization principle in quantum mechanics. The transport properties of the gas, such as viscosity and thermal conductivity, have been calculated and found to be strongly dependent on P below a few kelvins. Spin transport in /sup 3/He increasing gives rise at low temperature to collective oscillatory modes: the transverse spin waves. Large changes are also expected with P in the case of more dense /sup 3/He fluids, such as an increase with P in the saturated vapor pressure. Optical pumping is a convenient technique for efficient polarization of the nuclear spins in /sup 3/He gas/sup 2/ making use of the 2/sup 3/S-2/sup 3/P atomic line at 1.08 μm. The arrival of cw tunable lasers in the near IR in the early 1980s gave a strong impulse to the buildup of experiments with a view to measuring quantum properties of /sup 3/He increasing at low temperature. Color center lasers (F/sup +//sub 2/ in NaF) provide P values up to 70%. They are now being replaced by more easy to handle LNA lasers which have given so far P in excess of 50% at room temperature. At low temperature, direct optical pumping of a /sup 3/He cell leads to poor P values; for that reason a different technique is used

Results of the Abbott RealTime HIV-1 assay for specimens yielding "target not detected" results by the Cobas AmpliPrep/Cobas TaqMan HIV-1 Test.

Science.gov (United States)

Babady, N Esther; Germer, Jeffrey J; Yao, Joseph D C

2010-03-01

No significantly discordant results were observed between the Abbott RealTime HIV-1 assay and the COBAS AmpliPrep/COBAS TaqMan HIV-1 Test (CTM) among 1,190 unique clinical plasma specimens obtained from laboratories located in 40 states representing all nine U.S. geographic regions and previously yielding "target not detected" results by CTM.

Quantificação de ácido alfa-linolênico em caules e folhas de linho (Linum usitatissimum L. colhidos em diferentes estágios de desenvolvimento Quantification of alpha-linolenic acid in stems and leaves of flax (Linum usitatissimum L. harvested in different stages of development

Directory of Open Access Journals (Sweden)

Ana Carolina de Aguiar

2010-12-01

Full Text Available O objetivo deste estudo foi quantificar o ácido alfa-linolênico [LNA, 18:3 (n-3], avaliar a composição centesimal das folhas e caules de linho (Linum usitatissimum L. submetidos à secagem e colhidos em diferentes estágios de desenvolvimento (40, 80 e 120 dias, e determinar o potencial antioxidante das folhas colhidas aos 80 dias através do teste com o radical DPPH. As folhas obtiveram maiores teores de cinzas, proteína e lipídios totais em relação aos caules. Tanto as folhas quanto os caules apresentaram razões de AGPI/AGS e n-6/n-3 dentro dos valores considerados adequados para a alimentação. Os caules colhidos nos diferentes tempos não apresentaram diferenças significativas (PThe objective of this study was to quantify the alpha-linolenic acid [LNA, 18:3 (n-3] and to evaluate the proximate composition of leaves and stems of flax (Linum usitatissimum L. dried and harvested at different stages of development (40, 80 and 120 days, and to determine the antioxidant potential of the leaf harvested at 80 days using the test of DPPH radical. The leaves had higher levels of ash, protein and total lipids when compared to the stems. Both the leaves as the stems had ratios of PUFA/SFA and n-6/n-3 within the values considered suitable for food. Stems in the different stages showed no significant difference (P<0.05 of LNA content. Leaves harvested at 80 days showed the highest concentration of LNA, corresponding to 1,262.36 mg/100g dried leaf. The different extracts (methanol, butanol, acetate and water were efficient in the inhibition of DPPH radical, with emphasis on the butanolic and acetate fractions and the values of IC50 were approximately 42 ppm. These results highlight the nutritional potential and antioxidant activity of leaves and stems of flaxseed for future use in the animal and human feeding.

A Pilot Study: Effects of Dietary Supplementation with α-Linolenic Acid-Enriched Perilla Seed Oil on Bronchial Asthma

Directory of Open Access Journals (Sweden)

Kozo Ashida

1997-01-01

Full Text Available N-3 fatty acids, such as fish oil, have been reported to have some beneficial effects in patients with bronchial asthma. The effects of dietary supplementation with perilla seed oil rich in a-linolenic acid (α-LNA, parent n-3 fatty acid, were studied in five patients with asthma. The symptoms of asthma and mean peak flow rates (PFR both early in the morning and in the evening were improved 2 weeks after dietary supplementation and the increases in PFR were significant (P<0.05. The generation of leukotriene B4 (LTB4 by peripheral leukocytes stimulated with the Ca2+ ionophore A23187 was significantly suppressed from 77.6 to 41.6 ng/5Xl06 cells by dietary supplementation (P<0.05. The generation of leukotriene C4 (LTC4 by leukocytes was also significantly suppressed from 64.0 to 38.8 ng/5x106 cells after supplementation with perilla seed oil (P<0.05. These results suggest that dietary supplementation with perilla seed oil is beneficial for the treatment of asthma.

A quantitative PCR (TaqMan assay for pathogenic Leptospira spp

Directory of Open Access Journals (Sweden)

Symonds Meegan L

2002-07-01

Full Text Available Abstract Background Leptospirosis is an emerging infectious disease. The differential diagnosis of leptospirosis is difficult due to the varied and often "flu like" symptoms which may result in a missed or delayed diagnosis. There are over 230 known serovars in the genus Leptospira. Confirmatory serological diagnosis of leptospirosis is usually made using the microscopic agglutination test (MAT which relies on the use of live cultures as the source of antigen, often performed using a panel of antigens representative of local serovars. Other techniques, such as the enzyme linked immunosorbent assay (ELISA and slide agglutination test (SAT, can detect different classes of antibody but may be subject to false positive reactions and require confirmation of these results by the MAT. Methods The polymerase chain reaction (PCR has been used to detect a large number of microorganisms, including those of clinical significance. The sensitivity of PCR often precludes the need for isolation and culture, thus making it ideal for the rapid detection of organisms involved in acute infections. We employed real-time (quantitative PCR using TaqMan chemistry to detect leptospires in clinical and environmental samples. Results and Conclusions The PCR assay can be applied to either blood or urine samples and does not rely on the isolation and culture of the organism. Capability exists for automation and high throughput testing in a clinical laboratory. It is specific for Leptospira and may discriminate pathogenic and non-pathogenic species. The limit of detection is as low as two cells.

TaqMan real-time PCR assays for single-nucleotide polymorphisms which identify Francisella tularensis and its subspecies and subpopulations.

Directory of Open Access Journals (Sweden)

Dawn N Birdsell

Full Text Available Francisella tularensis, the etiologic agent of tularemia and a Class A Select Agent, is divided into three subspecies and multiple subpopulations that differ in virulence and geographic distribution. Given these differences, there is a need to rapidly and accurately determine if a strain is F. tularensis and, if it is, assign it to subspecies and subpopulation. We designed TaqMan real-time PCR genotyping assays using eleven single nucleotide polymorphisms (SNPs that were potentially specific to closely related groups within the genus Francisella, including numerous subpopulations within F. tularensis species. We performed extensive validation studies to test the specificity of these SNPs to particular populations by screening the assays across a set of 565 genetically and geographically diverse F. tularensis isolates and an additional 21 genetic near-neighbor (outgroup isolates. All eleven assays correctly determined the genetic groups of all 565 F. tularensis isolates. One assay differentiates F. tularensis, F. novicida, and F. hispaniensis from the more genetically distant F. philomiragia and Francisella-like endosymbionts. Another assay differentiates F. tularensis isolates from near neighbors. The remaining nine assays classify F. tularensis-confirmed isolates into F. tularensis subspecies and subpopulations. The genotyping accuracy of these nine assays diminished when tested on outgroup isolates (i.e. non F. tularensis, therefore a hierarchical approach of assay usage is recommended wherein the F. tularensis-specific assay is used before the nine downstream assays. Among F. tularensis isolates, all eleven assays were highly sensitive, consistently amplifying very low concentrations of DNA. Altogether, these eleven TaqMan real-time PCR assays represent a highly accurate, rapid, and sensitive means of identifying the species, subspecies, and subpopulation of any F. tularensis isolate if used in a step-wise hierarchical scheme. These assays

Results of the Abbott RealTime HIV-1 Assay for Specimens Yielding “Target Not Detected” Results by the Cobas AmpliPrep/Cobas TaqMan HIV-1 Test▿

OpenAIRE

Babady, N. Esther; Germer, Jeffrey J.; Yao, Joseph D. C.

2009-01-01

No significantly discordant results were observed between the Abbott RealTime HIV-1 assay and the COBAS AmpliPrep/COBAS TaqMan HIV-1 Test (CTM) among 1,190 unique clinical plasma specimens obtained from laboratories located in 40 states representing all nine U.S. geographic regions and previously yielding “target not detected” results by CTM.

Demonstration of Hepatitis C Virus RNA with In Situ Hybridization Employing a Locked Nucleic Acid Probe in Humanized Liver of Infected Chimeric Mice and in Needle-Biopsied Human Liver

Directory of Open Access Journals (Sweden)

Kazuya Shiogama

2013-01-01

Full Text Available Background. In situ hybridization (ISH with high sensitivity has been requested to demonstrate hepatitis C virus (HCV RNA in formalin-fixed, paraffin-embedded (FFPE sections of the liver. Methods. ISH employing a locked-nucleic-acid- (LNA-modified oligonucleotide probe and biotin-free catalyzed signal amplification system (CSAII was applied to HCV-RNA detection in the liver tissue. Nested reverse-transcription polymerase chain reaction (RT-PCR was performed for HCV genotyping using total RNA extracted from FFPE sections. The target tissues included FFPE tissue sections of humanized livers in HCV-infected chimeric mice (HCV genotypes 1a, 1b, and 2a and noninfected and of needle-biopsied livers from HCV-infected patients. Results. HCV-RNA was demonstrated with the ISH technique in HCV-infected liver tissues from both chimeric mice and 9 (82% of 11 patients with HCV infection. The HCV signals were sensitive to RNase. Nested RT-PCR confirmed the genotype in 8 (73% of 11 livers (type 1b: 6 lesions and type 2a: 2 lesions. HCV-RNA was not identified in chronic hepatitis B lesions, fatty liver, autoimmune hepatitis, and hepatocellular carcinoma. Conclusion. ISH using the LNA-modified oligonucleotide probe and CSAII was applicable to detecting HCV-RNA in routinely prepared FFPE liver specimens.

Cross-platform comparison of SYBR® Green real-time PCR with TaqMan PCR, microarrays and other gene expression measurement technologies evaluated in the MicroArray Quality Control (MAQC study

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Dial Stacey L

2008-07-01

Full Text Available Abstract Background The MicroArray Quality Control (MAQC project evaluated the inter- and intra-platform reproducibility of seven microarray platforms and three quantitative gene expression assays in profiling the expression of two commercially available Reference RNA samples (Nat Biotechnol 24:1115-22, 2006. The tested microarrays were the platforms from Affymetrix, Agilent Technologies, Applied Biosystems, GE Healthcare, Illumina, Eppendorf and the National Cancer Institute, and quantitative gene expression assays included TaqMan® Gene Expression PCR Assay, Standardized (Sta RT-PCR™ and QuantiGene®. The data showed great consistency in gene expression measurements across different microarray platforms, different technologies and test sites. However, SYBR® Green real-time PCR, another common technique utilized by half of all real-time PCR users for gene expression measurement, was not addressed in the MAQC study. In the present study, we compared the performance of SYBR Green PCR with TaqMan PCR, microarrays and other quantitative technologies using the same two Reference RNA samples as the MAQC project. We assessed SYBR Green real-time PCR using commercially available RT2 Profiler™ PCR Arrays from SuperArray, containing primer pairs that have been experimentally validated to ensure gene-specificity and high amplification efficiency. Results The SYBR Green PCR Arrays exhibit good reproducibility among different users, PCR instruments and test sites. In addition, the SYBR Green PCR Arrays have the highest concordance with TaqMan PCR, and a high level of concordance with other quantitative methods and microarrays that were evaluated in this study in terms of fold-change correlation and overlap of lists of differentially expressed genes. Conclusion These data demonstrate that SYBR Green real-time PCR delivers highly comparable results in gene expression measurement with TaqMan PCR and other high-density microarrays.

Fluorescence In Vivo Hybridization (FIVH) for Detection of Helicobacter pylori Infection in a C57BL/6 Mouse Model

DEFF Research Database (Denmark)

Fontenete, Sílvia; Leite, Marina; Cappoen, Davie

2016-01-01

). Finally, the efficiency of FIVH to detect H. pylori SS1 strain in C57BL/6 infected mice was evaluated ex vivo in mucus samples, in cryosections and paraffin-embedded sections by epifluorescence and confocal microscopy. RESULTS: H. pylori SS1 strain infecting C57BL/6 mice was successfully detected...... by the Cy3_HP_LNA/2OMe_PS probe in the mucus, attached to gastric epithelial cells and colonizing the gastric pits. The specificity of the probe for H. pylori was confirmed by microscopy. CONCLUSIONS: In the future this methodology can be used in combination with a confocal laser endomicroscope for in vivo......INTRODUCTION: In this study, we applied fluorescence in vivo hybridization (FIVH) using locked nucleic acid (LNA) probes targeting the bacterial rRNA gene for in vivo detection of H. pylori infecting the C57BL/6 mouse model. A previously designed Cy3_HP_LNA/2OMe_PS probe, complementary...

A hyaluronic acid-based hydrogel enabling CD44-mediated chondrocyte binding and gapmer oligonucleotide release for modulation of gene expression in osteoarthritis

DEFF Research Database (Denmark)

Cai, Yunpeng; López-Ruiz, Elena; Wengel, Jesper

2017-01-01

Hyaluronic acid (HA) is an attractive biomaterial for osteoarthritis (OA) treatment due to inherent functional and compatibility properties as an endogenous knee joint component. In this work, we describe a HA-based hydrogel with the dual functionality of increased CD44-dependent chondrocyte......:3) for identifying designs displaying optimal engagement of OA patient-derived CD44-expressing chondrocytes. Correlation was found between cell binding and CD44 expression, with maximal binding exhibited at a HA/chitosan ratio of 7:3, that was 181% higher than CD44-negative MCF-7 cell control cells. Transfection...... agent-free uptake into OA chondrocytes of fluorescent 13-mer DNA oligonucleotides with a flanked locked nucleic acid (LNA) gapmer design, in contrast to naked siRNA, was demonstrated by confocal and flow cytometric analysis. A sustained and complete release over 5days was found with the 7:3 hydrogel...

Development of a TaqMan Array Card for Acute-Febrile-Illness Outbreak Investigation and Surveillance of Emerging Pathogens, Including Ebola Virus.

Science.gov (United States)

Liu, Jie; Ochieng, Caroline; Wiersma, Steve; Ströher, Ute; Towner, Jonathan S; Whitmer, Shannon; Nichol, Stuart T; Moore, Christopher C; Kersh, Gilbert J; Kato, Cecilia; Sexton, Christopher; Petersen, Jeannine; Massung, Robert; Hercik, Christine; Crump, John A; Kibiki, Gibson; Maro, Athanasia; Mujaga, Buliga; Gratz, Jean; Jacob, Shevin T; Banura, Patrick; Scheld, W Michael; Juma, Bonventure; Onyango, Clayton O; Montgomery, Joel M; Houpt, Eric; Fields, Barry

2016-01-01

Acute febrile illness (AFI) is associated with substantial morbidity and mortality worldwide, yet an etiologic agent is often not identified. Convalescent-phase serology is impractical, blood culture is slow, and many pathogens are fastidious or impossible to cultivate. We developed a real-time PCR-based TaqMan array card (TAC) that can test six to eight samples within 2.5 h from sample to results and can simultaneously detect 26 AFI-associated organisms, including 15 viruses (chikungunya, Crimean-Congo hemorrhagic fever [CCHF] virus, dengue, Ebola virus, Bundibugyo virus, Sudan virus, hantaviruses [Hantaan and Seoul], hepatitis E, Marburg, Nipah virus, o'nyong-nyong virus, Rift Valley fever virus, West Nile virus, and yellow fever virus), 8 bacteria (Bartonella spp., Brucella spp., Coxiella burnetii, Leptospira spp., Rickettsia spp., Salmonella enterica and Salmonella enterica serovar Typhi, and Yersinia pestis), and 3 protozoa (Leishmania spp., Plasmodium spp., and Trypanosoma brucei). Two extrinsic controls (phocine herpesvirus 1 and bacteriophage MS2) were included to ensure extraction and amplification efficiency. Analytical validation was performed on spiked specimens for linearity, intra-assay precision, interassay precision, limit of detection, and specificity. The performance of the card on clinical specimens was evaluated with 1,050 blood samples by comparison to the individual real-time PCR assays, and the TAC exhibited an overall 88% (278/315; 95% confidence interval [CI], 84% to 92%) sensitivity and a 99% (5,261/5,326, 98% to 99%) specificity. This TaqMan array card can be used in field settings as a rapid screen for outbreak investigation or for the surveillance of pathogens, including Ebola virus. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Heterotrophic bacterial responses to the winter–spring phytoplankton bloom in open waters of the NW Mediterranean

KAUST Repository

Gomes, Ana; Gasol, Josep M.; Estrada, Marta; Franco-Vidal, Leticia; Dí az-Pé rez, Laura; Ferrera, Isabel; Moran, Xose Anxelu G.

2014-01-01

and bacterioplankton biomass and production were complemented with an insight into bacterial physiological structure by single-cell analysis of nucleic acid content [low (LNA) vs. high (HNA)] and membrane integrity (“Live” vs. “Dead” cells). Bacterial production

Development and Validation of a TaqMan Real-Time PCR Assay for the Specific Detection and Quantification of Fusarium fujikuroi in Rice Plants and Seeds.

Science.gov (United States)

Carneiro, Greice Amaral; Matić, Slavica; Ortu, Giuseppe; Garibaldi, Angelo; Spadaro, Davide; Gullino, Maria Lodovica

2017-07-01

Bakanae disease, which is caused by the seedborne pathogen Fusarium fujikuroi, is found throughout the world on rice. A TaqMan real-time PCR has been developed on the TEF 1-α gene to detect F. fujikuroi in different rice tissues. Three primer/probe sets were tested. The selected set produced an amplicon of 84 bp and was specific for F. fujikuroi with respect to eight Fusarium species of rice and six other rice common pathogens. The assay was validated for specificity, selectivity, sensitivity, repeatability, and reproducibility. The detection limit was set at 27.5 fg of DNA, which is approximately equivalent to one haploid genome of F. fujikuroi. The developed TaqMan real-time assay was able to efficiently detect and quantify F. fujikuroi from rice culms, leaves, roots, and seeds. At 1 week post-germination (wpg), the pathogen was more diffused in the green tissues, while at 3 wpg it was uniformly spread also in the roots. The highest concentration of F. fujikuroi was measured in the M6 cultivar, which showed around 1,450 fungal cells/g. The assay was sufficiently sensitive to detect a few genomic equivalents in the rice seeds, corresponding to 9.89 F. fujikuroi cells/g. The assay permitted bakanae disease to be detected in asymptomatic tissues at the early rice development stages.

Purslane weed (Portulaca oleracea): a prospective plant source of nutrition, omega-3 fatty acid, and antioxidant attributes.

Science.gov (United States)

Uddin, Md Kamal; Juraimi, Abdul Shukor; Hossain, Md Sabir; Nahar, Most Altaf Un; Ali, Md Eaqub; Rahman, M M

2014-01-01

Purslane (Portulaca oleracea L.) is an important plant naturally found as a weed in field crops and lawns. Purslane is widely distributed around the globe and is popular as a potherb in many areas of Europe, Asia, and the Mediterranean region. This plant possesses mucilaginous substances which are of medicinal importance. It is a rich source of potassium (494 mg/100 g) followed by magnesium (68 mg/100 g) and calcium (65 mg/100 g) and possesses the potential to be used as vegetable source of omega-3 fatty acid. It is very good source of alpha-linolenic acid (ALA) and gamma-linolenic acid (LNA, 18 : 3 w3) (4 mg/g fresh weight) of any green leafy vegetable. It contained the highest amount (22.2 mg and 130 mg per 100 g of fresh and dry weight, resp.) of alpha-tocopherol and ascorbic acid (26.6 mg and 506 mg per 100 g of fresh and dry weight, resp.). The oxalate content of purslane leaves was reported as 671-869 mg/100 g fresh weight. The antioxidant content and nutritional value of purslane are important for human consumption. It revealed tremendous nutritional potential and has indicated the potential use of this herb for the future.

Performance evaluation of cobas HBV real-time PCR assay on Roche cobas 4800 System in comparison with COBAS AmpliPrep/COBAS TaqMan HBV Test.

Science.gov (United States)

Kim, Hanah; Hur, Mina; Bae, Eunsin; Lee, Kyung-A; Lee, Woo-In

2018-02-19

Hepatitis B virus (HBV) nucleic acid amplification testing (NAAT) is important for the diagnosis and management of HBV infection. We evaluated the analytical performance of the cobas HBV NAAT (Roche Diagnostics GmbH, Mannheim, Germany) on the cobas 4800 System in comparison with COBAS AmpliPrep/COBAS TaqMan HBV Test (CAP/CTM HBV). Precision was evaluated using three levels of cobas HBV/HCV/HIV-1 Control Kit, and linearity was evaluated across the anticipated measuring range (10.0-1.0×109 IU/mL) at seven levels using clinical samples. Detection capability, including limit of blank (LOB), limit of detection (LOD) and limit of quantitation (LOQ), was verified using the 4th WHO International Standard for HBV DNA for NAT (NIBSC code: 10/266). Correlation between the two systems was compared using 205 clinical samples (102 sera and 103 EDTA plasma). Repeatability and total imprecision (coefficient of variation) ranged from 0.5% to 3.8% and from 0.5% to 3.5%, respectively. Linearity (coefficient of determination, R2) was 0.999. LOB, LOD and LOQ were all acceptable within the observed proportion rate (85%). Correlation was very high between the two systems in both serum and plasma samples (correlation coefficient [r]=0.995). The new cobas HBV real-time PCR assay on the cobas 4800 System showed reliable analytical performances.

Evaluation of the Aptima HBV Quant assay vs. the COBAS TaqMan HBV test using the high pure system for the quantitation of HBV DNA in plasma and serum samples.

Science.gov (United States)

Schalasta, Gunnar; Börner, Anna; Speicher, Andrea; Enders, Martin

2018-03-28

Proper management of patients with chronic hepatitis B virus (HBV) infection requires monitoring of plasma or serum HBV DNA levels using a highly sensitive nucleic acid amplification test. Because commercially available assays differ in performance, we compared herein the performance of the Hologic Aptima HBV Quant assay (Aptima) to that of the Roche Cobas TaqMan HBV test for use with the high pure system (HPS/CTM). Assay performance was assessed using HBV reference panels as well as plasma and serum samples from chronically HBV-infected patients. Method correlation, analytical sensitivity, precision/reproducibility, linearity, bias and influence of genotype were evaluated. Data analysis was performed using linear regression, Deming correlation analysis and Bland-Altman analysis. Agreement between the assays for the two reference panels was good, with a difference in assay values vs. target 0.98). The two assays had similar bias and precision across the different genotypes tested at low viral loads (25-1000 IU/mL). Aptima has a performance comparable with that of HPS/CTM, making it suitable for use for HBV infection monitoring. Aptima runs on a fully automated platform (the Panther system) and therefore offers a significantly improved workflow compared with HPS/CTM.

Lack of anti-tumor activity with the β-catenin expression inhibitor EZN-3892 in the C57BL/6J Min/+ model of intestinal carcinogenesis

Energy Technology Data Exchange (ETDEWEB)

Hasson, Rian M.; Briggs, Alexandra; Rizvi, Hira; Carothers, Adelaide M.; Davids, Jennifer S.; Bertagnolli, Monica M.; Cho, Nancy L., E-mail: nlcho@partners.org

2014-02-14

Highlights: • Wnt/β-catenin signaling is aberrantly activated in most colorectal cancers. • Locked nucleic acid (LNA)-based antisense is a novel tool for cancer therapy. • β-Catenin inhibition was observed in mature intestinal tissue of LNA-treated mice. • Further investigation of Wnt/β-catenin targeted therapies is warranted. - Abstract: Background: Previously, we showed that short-term inhibition of β-catenin expression and reversal of aberrant β-catenin subcellular localization by the selective COX-2 inhibitor celecoxib is associated with adenoma regression in the C57BL/6J Min/+ mouse. Conversly, long-term administration resulted in tumor resistance, leading us to investigate alternative methods for selective β-catenin chemoprevention. In this study, we hypothesized that disruption of β-catenin expression by EZN-3892, a selective locked nucleic acid (LNA)-based β-catenin inhibitor, would counteract the tumorigenic effect of Apc loss in Min/+ adenomas while preserving normal intestinal function. Materials and methods: C57BL/6J Apc{sup +/+} wild-type (WT) and Min/+ mice were treated with the maximum tolerated dose (MTD) of EZN-3892 (30 mg/kg). Drug effect on tumor numbers, β-catenin protein expression, and nuclear β-catenin localization were determined. Results: Although the tumor phenotype and β-catenin nuclear localization in Min/+ mice did not change following drug administration, we observed a decrease in β-catenin expression levels in the mature intestinal tissue of treated Min/+ and WT mice, providing proof of principle regarding successful delivery of the LNA-based antisense vehicle. Higher doses of EZN-3892 resulted in fatal outcomes in Min/+ mice, likely due to β-catenin ablation in the intestinal tissue and loss of function. Conclusions: Our data support the critical role of Wnt/β-catenin signaling in maintaining intestinal homeostasis and highlight the challenges of effective drug delivery to target disease without permanent

Development of TaqMan probes targeting the four major celiac disease epitopes found in α-gliadin sequences of spelt (Triticum aestivum ssp. spelta) and bread wheat (Triticum aestivum ssp. aestivum).

Science.gov (United States)

Dubois, Benjamin; Bertin, Pierre; Muhovski, Yordan; Escarnot, Emmanuelle; Mingeot, Dominique

2017-01-01

Celiac disease (CD) is caused by specific sequences of gluten proteins found in cereals such as bread wheat ( Triticum aestivum ssp. aestivum ) and spelt ( T. aestivum ssp. spelta ). Among them, the α-gliadins display the highest immunogenicity, with four T-cell stimulatory epitopes. The toxicity of each epitope sequence can be reduced or even suppressed according to the allelic form of each sequence. One way to address the CD problem would be to make use of this allelic variability in breeding programs to develop safe varieties, but tools to track the presence of toxic epitopes are required. The objective of this study was to develop a tool to accurately detect and quantify the immunogenic content of expressed α-gliadins of spelt and bread wheat. Four TaqMan probes that only hybridize to the canonical-i.e. toxic-form of each of the four epitopes were developed and their specificity was demonstrated. Six TaqMan probes targeting stable reference genes were also developed and constitute a tool to normalize qPCR data. The probes were used to measure the epitope expression levels of 11 contrasted spelt accessions and three ancestral diploid accessions of bread wheat and spelt. A high expression variability was highlighted among epitopes and among accessions, especially in Asian spelts, which showed lower epitope expression levels than the other spelts. Some discrepancies were identified between the canonical epitope expression level and the global amount of expressed α-gliadins, which makes the designed TaqMan probes a useful tool to quantify the immunogenic potential independently of the global amount of expressed α-gliadins. The results obtained in this study provide useful tools to study the immunogenic potential of expressed α-gliadin sequences from Triticeae accessions such as spelt and bread wheat. The application of the designed probes to contrasted spelt accessions revealed a high variability and interesting low canonical epitope expression levels in the

Triplex-forming ability of modified oligonucleotides

DEFF Research Database (Denmark)

Højland, Torben; Babu, Bolle Ravindra; Bryld, Torsten

2007-01-01

We present our studies on the ability of several different nucleotide analogs as triplex-forming oligonucleotides. The modifications tested include 4'-C-hydroxymethyl, LNA, 2'-amino-LNA and N2'-functionalized 2'-amino-LNA. Triplexes containing monomers of N2'-glycyl-functionalized 2'-amino-LNA ar...

Development of a TaqMan Allelic Discrimination Assay for detection of Single Nucleotides Polymorphisms associated with anti-malarial drug resistance

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Kamau Edwin

2012-01-01

Full Text Available Abstract Background Anti-malarial drug resistance poses a threat to current global efforts towards control and elimination of malaria. Several methods are used in monitoring anti-malarial drug resistance. Molecular markers such as single nucleotide polymorphism (SNP for example are increasingly being used to identify genetic mutations related to anti-malarial drug resistance. Several methods are currently being used in analysis of SNP associated with anti-malarial drug resistance and although each one of these methods has unique strengths and shortcoming, there is still need to improve and/or develop new methods that will close the gap found in the current methods. Methods TaqMan Allelic Discrimination assays for detection of SNPs associated with anti-malarial drug resistance were designed for analysis on Applied Biosystems PCR platform. These assays were designed by submitting SNP sequences associated with anti-malarial drug resistance to Applied Biosystems website. Eleven SNPs associated with resistance to anti-malarial drugs were selected and tested. The performance of each SNP assay was tested by creating plasmid DNAs carrying codons of interests and analysing them for analysis. To test the sensitivity and specificity of each SNP assay, 12 clinical samples were sequenced at codons of interest and used in the analysis. Plasmid DNAs were used to establish the Limit of Detection (LoD for each assay. Results Data from genetic profiles of the Plasmodium falciparum laboratory strains and sequence data from 12 clinical samples was used as the reference method with which the performance of the SNP assays were compared to. The sensitivity and specificity of each SNP assay was establish at 100%. LoD for each assay was established at 2 GE, equivalent to less than 1 parasite/μL. SNP assays performed well in detecting mixed infection and analysis of clinical samples. Conclusion TaqMan Allelic Discrimination assay provides a good alternative tool in

Defense Priming and Jasmonates: A Role for Free Fatty Acids in Insect Elicitor-Induced Long Distance Signaling

Science.gov (United States)

Li, Ting; Cofer, Tristan; Engelberth, Marie; Engelberth, Jurgen

2016-01-01

Green leaf volatiles (GLV) prime plants against insect herbivore attack resulting in stronger and faster signaling by jasmonic acid (JA). In maize this response is specifically linked to insect elicitor (IE)-induced signaling processes, which cause JA accumulation not only around the damage site, but also in distant tissues, presumably through the activation of electrical signals. Here, we present additional data further characterizing these distal signaling events in maize. Also, we describe how exposure to GLV increases free fatty acid (fFA) levels in maize seedlings, but also in other plants, and how increased fFA levels affect IE-induced JA accumulation. Increased fFA, in particular α-linolenic acid (LnA), caused a significant increase in JA accumulation after IE treatment, while JA induced by mechanical wounding (MW) alone was not affected. We also identified treatments that significantly decreased certain fFA level including simulated wind and rain. In such treated plants, IE-induced JA accumulation was significantly reduced when compared to un-moved control plants, while MW-induced JA accumulation was not significantly affected. Since only IE-induced JA accumulation was altered by changes in the fFA composition, we conclude that changing levels of fFA affect primarily IE-induced signaling processes rather than serving as a substrate for JA. PMID:27135225

Next-generation bis-locked nucleic acids with stacking linker and 2'-glycylamino-LNA show enhanced DNA invasion into supercoiled duplexes

DEFF Research Database (Denmark)

Geny, Sylvain; Moreno, Pedro M D; Krzywkowski, Tomasz

2016-01-01

Targeting and invading double-stranded DNA with synthetic oligonucleotides under physiological conditions remain a challenge. Bis-locked nucleic acids (bisLNAs) are clamp-forming oligonucleotides able to invade into supercoiled DNA via combined Hoogsteen and Watson-Crick binding. To improve the b...

Development of a Rickettsia bellii-Specific TaqMan Assay Targeting the Citrate Synthase Gene.

Science.gov (United States)

Hecht, Joy A; Allerdice, Michelle E J; Krawczak, Felipe S; Labruna, Marcelo B; Paddock, Christopher D; Karpathy, Sandor E

2016-11-01

Rickettsia bellii is a rickettsial species of unknown pathogenicity that infects argasid and ixodid ticks throughout the Americas. Many molecular assays used to detect spotted fever group (SFG) Rickettsia species do not detect R. bellii, so that infection with this bacterium may be concealed in tick populations when assays are used that screen specifically for SFG rickettsiae. We describe the development and validation of a R. bellii-specific, quantitative, real-time PCR TaqMan assay that targets a segment of the citrate synthase (gltA) gene. The specificity of this assay was validated against a panel of DNA samples that included 26 species of Rickettsia, Orientia, Ehrlichia, Anaplasma, and Bartonella, five samples of tick and human DNA, and DNA from 20 isolates of R. bellii, including 11 from North America and nine from South America. A R. bellii control plasmid was constructed, and serial dilutions of the plasmid were used to determine the limit of detection of the assay to be one copy per 4 µl of template DNA. This assay can be used to better determine the role of R. bellii in the epidemiology of tick-borne rickettsioses in the Western Hemisphere. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.

Therapeutic silencing of microRNA-122 in primates with chronic hepatitis C virus infection

DEFF Research Database (Denmark)

Lanford, Robert E; Hildebrandt-Eriksen, Elisabeth S; Petri, Andreas

2010-01-01

The liver-expressed microRNA-122 (miR-122) is essential for hepatitis C virus (HCV) RNA accumulation in cultured liver cells, but its potential as a target for antiviral intervention has not been assessed. We found that treatment of chronically infected chimpanzees with a locked nucleic acid (LNA...

The ω-3-poly-unsaturated fatty acids and the function of the brain and retina in infants

DEFF Research Database (Denmark)

Lauritzen, Lotte; Damsgaard, Camilla Trab; Andersen, Anders Daniel

2007-01-01

The central nervous system of human infants has a uniquely high content of docosahexaenoic acid (DHA, 22:6¿-3), which is accreted during the brain growth spurt that occurs during the first year of life. Based on results from randomized controlled trials on visual acuity it is presently agreed...... LNA could meet the ¿-3 PUFA requirements. Moreover, the potential long-term implications of the early improvements in visual function are not known. ¿-3 PUFA intake in the first year of life is also believed to affect infant cognitive development, although this question remains unresolved. Breast......-developmental outcomes, mirroring the results of observational studies. Some of these studies indicate possible negative effects of ¿-3 LCPUFA, e.g. on language development, but the interpretation is complicated by lack of knowledge of the long-term predictive role of the employed early tests on cognitive development...

A quantitative TaqMan PCR assay for the detection of Ureaplasma diversum.

Science.gov (United States)

Marques, Lucas M; Amorim, Aline T; Martins, Hellen Braga; Rezende, Izadora Souza; Barbosa, Maysa Santos; Lobão, Tassia Neves; Campos, Guilherme B; Timenetsky, Jorge

2013-12-27

Ureaplasma diversum in veterinary studies is an undesirable microbe, which may cause infection in bulls and may result in seminal vesiculitis, balanopostitis, and alterations in spermatozoids, whereas in cows, it may cause placentitis, fetal alveolitis, abortion, and birth of weak calves. U. diversum is released through organic secretions, especially semen, preputial and vaginal mucus, conjunctival secretion, and milk. The aim of the present study was to develop a TaqMan probe, highly sensitive and specific quantitative PCR (qPCR) assay for the detection and quantification of U. diversum from genital swabs of bovines. Primers and probes specific to U. diversum 16S rRNA gene were designed. The specificity, detection limit, intra- and inter-assay variability of qPCR to detect this ureaplasma was compared with the results of the conventional PCR assay (cPCR). Swabs of vaginal mucus from 169 cows were tested. The qPCR assay detected as few as 10 copies of U. diversum and was 100-fold more sensitive than the cPCR. No cross-reactivity with other Mollicutes or eubacteria was observed. U. diversum was detected in 79 swabs (46.42%) by qPCR, while using cPCR it was detected in 42 (25%) samples. The difference in cPCR and qPCR ureaplasma detection between healthy and sick animals was not statistically significant. But the U. diversum load in samples from animals with genital disorders was higher than in healthy animals. The qPCR assay developed herein is highly sensitive and specific for the detection and quantification of U. diversum in vaginal bovine samples. Copyright © 2013. Published by Elsevier B.V.

Rapid Identification and Quantification of Aureococcus anophagefferens by qPCR Method (Taqman) in the Qinhuangdao Coastal Area: A Region for Recurrent Brown Tide Breakout in China.

Science.gov (United States)

Wang, Li-Ping; Lei, Kun

2016-12-01

Since 2009, Aureococcus anophagefferens has caused brown tide to occur recurrently in Qinhuangdao coastal area, China. Because the algal cells of A. anophagefferens are so tiny (~3 µm) that it is very hard to identify exactly under a microscope for natural water samples, it is very urgent to develop a method for efficient and continuous monitoring. Here specific primers and Taqman probe are designed to develop a real-time quantitative PCR (qPCR) method for identification and quantification continually. The algal community and cell abundance of A. anophagefferens in the study area (E 119°20'-119°50' and N 39°30'-39°50') from April to October in 2013 are detected by pyrosequencing, and are used to validate the specification and precision of qPCR method for natural samples. Both pyrosequencing and qPCR shows that the targeted cells are present only in May, June and July, and the cell abundance are July > June > May. Although there are various algal species including dinoflagellata, diatom, Cryptomonadales, Chrysophyceae and Chlorophyta living in the natural seawater simultaneously, no disturbance happens to qPCR method. This qPCR method could detect as few as 10 targeted cells, indicating it is able to detect the algal cells at pre-bloom levels. Therefore, qPCR with Taqman probe provides a powerful and sensitive method to monitor the brown tide continually in Qinhuangdao coastal area, China. The results provide a necessary technology support for forecasting the brown tide initiation, in China.

Comparison of the Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 test v1.0 with v2.0 in HIV-1 viral load quantification

Directory of Open Access Journals (Sweden)

Yi-Ching Tung

2015-04-01

Full Text Available Roche modified the COBAS AmpliPrep/COBAS TaqMan human immunodeficiency virus type 1 (HIV-1 test version 1.0 (CAP/CTM v1.0, resulting in the COBAS AmpliPrep/COBAS TaqMan HIV-1 test version 2.0 (CAP/CTM v2.0. The aim of this study was to evaluate the performance of the CAP/CTM v2.0 and to compare this performance with that of the CAP/CTM v1.0. The study was conducted in a small local study group in Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. A total of 86 plasma samples from HIV-1-seropositive patients were tested using the two assays. The correlation and concordance of results between the two assays were calculated. The CAP/CTM v2.0 generated higher values than did the CAP/CTM v1.0, and five samples (5.8% yielded a difference of > 1 log10 copies/mL. In addition, our data show that CAP/CTM v1.0 and CAP/CTM v2.0 yielded relatively consistent values for 23 samples with low viral loads (< 200 copies/mL. Furthermore, when viral loads were in a medium range (2–5 log10 copies/mL, the results of the two assays were more compatible. This study shows a good correlation between CAP/CTM v1.0 and v2.0 in HIV-1 viral load measurement. Further attention must be paid to those cases in which measured viral loads present larger differences between the two assays.

Australians are not Meeting the Recommended Intakes for Omega-3 Long Chain Polyunsaturated Fatty Acids: Results of an Analysis from the 2011–2012 National Nutrition and Physical Activity Survey

Directory of Open Access Journals (Sweden)

Barbara J. Meyer

2016-02-01

Full Text Available Health benefits have been attributed to omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA. Therefore it is important to know if Australians are currently meeting the recommended intake for n-3 LCPUFA and if they have increased since the last National Nutrition Survey in 1995 (NNS 1995. Dietary intake data was obtained from the recent 2011–2012 National Nutrition and Physical Activity Survey (2011–2012 NNPAS. Linoleic acid (LA intakes have decreased whilst alpha-linolenic acid (LNA and n-3 LCPUFA intakes have increased primarily due to n-3 LCPUFA supplements. The median n-3 LCPUFA intakes are less than 50% of the mean n-3 LCPUFA intakes which highlights the highly-skewed n-3 LCPUFA intakes, which shows that there are some people consuming high amounts of n-3 LCPUFA, but the vast majority of the population are consuming much lower amounts. Only 20% of the population meets the recommended n-3 LCPUFA intakes and only 10% of women of childbearing age meet the recommended docosahexaenoic acid (DHA intake. Fish and seafood is by far the richest source of n-3 LCPUFA including DHA.

Defense Priming and Jasmonates: A Role for Free Fatty Acids in Insect Elicitor-Induced Long Distance Signaling

Directory of Open Access Journals (Sweden)

Ting Li

2016-01-01

Full Text Available Green leaf volatiles (GLV prime plants against insect herbivore attack resulting in stronger and faster signaling by jasmonic acid (JA. In maize this response is specifically linked to insect elicitor (IE-induced signaling processes, which cause JA accumulation not only around the damage site, but also in distant tissues, presumably through the activation of electrical signals. Here, we present additional data further characterizing these distal signaling events in maize. Also, we describe how exposure to GLV increases free fatty acid (fFA levels in maize seedlings, but also in other plants, and how increased fFA levels affect IE-induced JA accumulation. Increased fFA, in particular α-linolenic acid (LnA, caused a significant increase in JA accumulation after IE treatment, while JA induced by mechanical wounding (MW alone was not affected. We also identified treatments that significantly decreased certain fFA level including simulated wind and rain. In such treated plants, IE-induced JA accumulation was significantly reduced when compared to un-moved control plants, while MW-induced JA accumulation was not significantly affected. Since only IE-induced JA accumulation was altered by changes in the fFA composition, we conclude that changing levels of fFA affect primarily IE-induced signaling processes rather than serving as a substrate for JA.

Application of Silver Ion High-Performance Liquid Chromatography for Quantitative Analysis of Selected n-3 and n-6 PUFA in Oil Supplements.

Science.gov (United States)

Czajkowska-Mysłek, Anna; Siekierko, Urszula; Gajewska, Magdalena

2016-04-01

The aim of this study was to develop a simple method for simultaneous determination of selected cis/cis PUFA-LNA (18:2), ALA (18:3), GLA (18:3), EPA (20:5), and DHA (22:6) by silver ion high-performance liquid chromatography coupled to a diode array detector (Ag-HPLC-DAD). The separation was performed on three Luna SCX Silver Loaded columns connected in series maintained at 10 °C with isocratic elution by 1% acetonitrile in n-hexane. The applied chromatographic system allowed a baseline separation of standard mixture of n-3 and n-6 fatty acid methyl esters containing LNA, DHA, and EPA and partial separation of ALA and GLA positional isomers. The method was validated by means of linearity, precision, stability, and recovery. Limits of detection (LOD) for considered PUFA standard solutions ranged from 0.27 to 0.43 mg L(-1). The developed method was used to evaluate of n-3 and n-6 fatty acids contents in plant and fish softgel oil capsules, results were compared with reference GC-FID based method.

Incorporation and fatty acid composition in liver of Nile tilapia fed with flaxseed oil = Incorporação e composição de ácidos graxos no fígado de tilápia-do-Nilo alimentada com óleo de linhaça

Directory of Open Access Journals (Sweden)

Polyana Batoqui França

2011-04-01

Full Text Available One of the most consumed freshwater fish in South America is Nile tilapia. The present study examined the effects of flaxseed oil (FO, source of alfa-linolenic acid (LNA, on the total lipid composition and polyunsaturated fatty acid, n-6 and n-3 PUFA, contents on Nile tilapia (Oreochromis niloticus liver. Tilapias were given diets with increasing levels 0.00, 1.2, 2.50, 3.75 and 5.00% (w w-1 of FO as a replacement of sunflower oil for five months. Fatty acids analysis ofmethyl esters revealed 45 fatty acids common to all treatments. The increase of flaxseed oil resulted in a decrease in total n-6 PUFA (35.1 to 21.1% and an increase in n-3 PUFA (3.3 to 18.5%. Thediet with LNA underwent sequential desaturation and elongation in liver, leading to an increase in all n-3 PUFA and a decrease in n-6/n-3 ratios (10.7 to 1.1. The manipulation of fatty acids with FOmay be used to increase n-3 PUFA and to help balance n-6/n-3 PUFA in dietary supplements, thus, the liver tilapia becomes one product with major nutritional value.A tilápia-do-Nilo é um dos peixes de água doce mais consumido na América do Sul. No presente experimento foram avaliados os efeitos do óleo de linhaça, fonte do ácido alfa-linolênico (LNA sobre a composição de lipídios totais e dos ácidos graxos poli-insaturados (AGPI das séries n-6 e n-3, contidos no fígado de tilápia-do-Nilo(Oreochromis niloticus. As tilápias receberam dietas com níveis de óleo de linhaça de 0,00; 1,25; 2,50; 3,75 e 5,00% (massa massa-1, em substituição ao óleo de girassol, por cinco meses. Nas análises dos ésteres metílicos de ácidos graxos foram detectados 45 ácidos graxos comuns em todos os tratamentos. O aumento na ingestão de óleo de linhaça resultou na diminuição do total de AGPI n-6 de 35,1 para 21,1% e um aumento de AGPI n-3 de 3,3 para 18,5% no fígado. OLNA, no fígado da tilápia, sofreu sequencial dessaturação e elongação, levando a um aumento de todos os AGPI n-3 e

Designing a time-effective TaqMan probe-based real-time polymerase chain reaction protocol for the identification of Yersinia enterocolitica in raw pork meat

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Milena Alicja Stachelska

2017-01-01

Full Text Available The aim of this study was to design a time-effective method comprising a short pre-enrichment step in a non-selective broth in combination with the TaqMan probe applied in the real-time polymerase chain reaction to detect Yersinia enterocolitica strains in raw pork meat. The method enabled to detect 1 colony forming unit per 25 mg of Yersinia enterocolitica in pork meat. The specificity and reliability of the method was not diminished by the company of microflora naturally present in meat. The method was found successful to detect pathogenic Yersinia enterocolitica strains in pork meat. It is advised to be used for assessing the microbial risk and for controlling the microbial quality of meat and meat products.

MicroRNA expression in the adult mouse central nervous system

DEFF Research Database (Denmark)

Bak, Mads; Silahtaroglu, Asli; Møller, Morten

2008-01-01

distinct areas of the adult mouse central nervous system (CNS). Microarray profiling in combination with real-time RT-PCR and LNA (locked nucleic acid)-based in situ hybridization uncovered 44 miRNAs displaying more than threefold enrichment in the spinal cord, cerebellum, medulla oblongata, pons......RNA-related gene regulatory networks in the mammalian central nervous system. Udgivelsesdato: 2008-Mar...

Quantitative Tetraplex Real-Time Polymerase Chain Reaction Assay with TaqMan Probes Discriminates Cattle, Buffalo, and Porcine Materials in Food Chain.

Science.gov (United States)

Hossain, M A Motalib; Ali, Md Eaqub; Sultana, Sharmin; Asing; Bonny, Sharmin Quazi; Kader, Md Abdul; Rahman, M Aminur

2017-05-17

Cattle, buffalo, and porcine materials are widely adulterated, and their quantification might safeguard health, religious, economic, and social sanctity. Recently, conventional polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) assays have been documented but they are just suitable for identification, cannot quantify adulterations. We described here a quantitative tetraplex real-time PCR assay with TaqMan Probes to quantify contributions from cattle, buffalo, and porcine materials simultaneously. Amplicon-sizes were very short (106-, 90-, and 146-bp for cattle, buffalo, and porcine) because longer targets could be broken down, bringing serious ambiguity in molecular diagnostics. False negative detection was eliminated through an endogenous control (141-bp site of eukaryotic 18S rRNA). Analysis of 27 frankfurters and 27 meatballs reflected 84-115% target recovery at 0.1-10% adulterations. Finally, a test of 36 commercial products revealed 71% beef frankfurters, 100% meatballs, and 85% burgers contained buffalo adulteration, but no porcine was found in beef products.

Improved Safety for Molecular Diagnosis of Classical Rabies Viruses by Use of a TaqMan Real-Time Reverse Transcription-PCR "Double Check" Strategy

DEFF Research Database (Denmark)

Hoffmann, B.; Freuling, C. M.; Wakeley, P. R.

2010-01-01

To improve the diagnosis of classical rabies virus with molecular methods, a validated, ready-to-use, real-time reverse transcription-PCR (RT-PCR) assay was developed. In a first step, primers and 6-carboxyfluorescien-labeled TaqMan probes specific for rabies virus were selected from the consensus...... sequence of the nucleoprotein gene of 203 different rabies virus sequences derived from GenBank. The selected primer-probe combination was highly specific and sensitive. During validation using a sample set of rabies virus strains from the virus archives of the Friedrich-Loeffler-Institut (FLI; Germany......), the Veterinary Laboratories Agency (VLA; United Kingdom), and the DTU National Veterinary Institute (Lindholm, Denmark), covering the global diversity of rabies virus lineages, it was shown that both the newly developed assay and a previously described one had some detection failures. This was overcome...

More, smaller bacteria in response to ocean's warming?

KAUST Repository

Moran, Xose Anxelu G.

2015-06-10

Heterotrophic bacteria play a major role in organic matter cycling in the ocean. Although the high abundances and relatively fast growth rates of coastal surface bacterioplankton make them suitable sentinels of global change, past analyses have largely overlooked this functional group. Here, time series analysis of a decade of monthly observations in temperate Atlantic coastal waters revealed strong seasonal patterns in the abundance, size and biomass of the ubiquitous flow-cytometric groups of low (LNA) and high nucleic acid (HNA) content bacteria. Over this relatively short period, we also found that bacterioplankton cells were significantly smaller, a trend that is consistent with the hypothesized temperature-driven decrease in body size. Although decadal cell shrinking was observed for both groups, it was only LNA cells that were strongly coherent, with ecological theories linking temperature, abundance and individual size on both the seasonal and interannual scale. We explain this finding because, relative to their HNA counterparts, marine LNA bacteria are less diverse, dominated by members of the SAR11 clade. Temperature manipulation experiments in 2012 confirmed a direct effect of warming on bacterial size. Concurrent with rising temperatures in spring, significant decadal trends of increasing standing stocks (3% per year) accompanied by decreasing mean cell size (-1% per year) suggest a major shift in community structure, with a larger contribution of LNA bacteria to total biomass. The increasing prevalence of these typically oligotrophic taxa may severely impact marine foodwebs and carbon fluxes by an overall decrease in the efficiency of the biological pump. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Association Between Stool Enteropathogen Quantity and Disease in Tanzanian Children Using TaqMan Array Cards: A Nested Case-Control Study

Science.gov (United States)

Platts-Mills, James A.; Gratz, Jean; Mduma, Esto; Svensen, Erling; Amour, Caroline; Liu, Jie; Maro, Athanasia; Saidi, Queen; Swai, Ndealilia; Kumburu, Happiness; McCormick, Benjamin J. J.; Kibiki, Gibson; Houpt, Eric R.

2014-01-01

Etiologic studies of diarrhea are limited by uneven diagnostic methods and frequent asymptomatic detection of enteropathogens. Polymerase chain reaction-based stool pathogen quantification may help distinguish clinically significant infections. We performed a nested case-control study of diarrhea in infants from a community-based birth cohort in Tanzania. We tested 71 diarrheal samples and pre-diarrheal matched controls with a laboratory-developed TaqMan Array Card for 19 enteropathogens. With qualitative detection, no pathogens were significantly associated with diarrhea. When pathogen quantity was considered, rotavirus (odds ratio [OR] = 2.70 per log10 increase, P < 0.001), astrovirus (OR = 1.49, P = 0.01), and Shigella/enteroinvasive Escherichia coli (OR = 1.47, P = 0.04) were associated with diarrhea. Enterotoxigenic E. coli (0.15 SD decline in length-for-age z score after 3 months per log10 increase, P < 0.001) and Campylobacter jejuni/C. coli (0.11 SD decline, P = 0.003) in pre-diarrheal stools were associated with poor linear growth. Quantitative analysis can help refine the association between enteropathogens and disease in endemic settings. PMID:24189366

DNA photocleavage by DNA and DNA-LNA amino acid-dye conjugates

Czech Academy of Sciences Publication Activity Database

Biton, A.; Ezra, A.; Kašpárková, Jana; Brabec, Viktor; Yavin, E.

2010-01-01

Roč. 21, č. 4 (2010), s. 616-621 ISSN 1043-1802 R&D Projects: GA AV ČR(CZ) IAA400040803 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : DNA * photocleavage * triplex forming oligonucleotides Subject RIV: BO - Biophysics Impact factor: 5.002, year: 2010

Synergy of Two Highly Specific Biomolecular Recognition Events

DEFF Research Database (Denmark)

Ejlersen, Maria; Christensen, Niels Johan; Sørensen, Kasper K

2018-01-01

Two highly specific biomolecular recognition events, nucleic acid duplex hybridization and DNA-peptide recognition in the minor groove, were coalesced in a miniature ensemble for the first time by covalently attaching a natural AT-hook peptide motif to nucleic acid duplexes via a 2'-amino......-LNA scaffold. A combination of molecular dynamics simulations and ultraviolet thermal denaturation studies revealed high sequence-specific affinity of the peptide-oligonucleotide conjugates (POCs) when binding to complementary DNA strands, leveraging the bioinformation encrypted in the minor groove of DNA...

A Ka-band low-noise amplifier with a coplanar waveguide (CPW) structure with 0.15-μm GaAs pHEMT technology

International Nuclear Information System (INIS)

Wu Chia-Song; Chang Chien-Huang; Liu Hsing-Chung; Lin Tah-Yeong; Wu Hsien-Ming

2010-01-01

This investigation explores a low-noise amplifier (LNA) with a coplanar waveguide (CPW) structure, in which a two-stage amplifier is associated with a cascade schematic circuit, implemented in 0.15-μm GaAs pseudomorphic high electron mobility transistor (pHEMT) technology in a Ka-band (26.5-40.0 GHz) microwave monolithic integrated circuit (MMIC). The experimental results demonstrate that the proposed LNA has a peak gain of 12.53 dB at 30 GHz and a minimum noise figure of 3.3 dB at 29.5 GHz, when biased at a V ds of 2 V and a V gs of -0.6 V with a drain current of 16 mA in the circuit. The results show that the millimeter-wave LNA with coplanar waveguide structure has a higher gain and wider bandwidth than a conventional circuit. Finally, the overall LNA characterization exhibits high gain and low noise, indicating that the LNA has a compact circuit and favorable RF characteristics. The strong RF character exhibited by the LNA circuit can be used in millimeter-wave circuit applications. (semiconductor integrated circuits)

Evaluation of miR-21 Inhibition and its Impact on Cancer Susceptibility Candidate 2 Long Noncoding RNA in Colorectal Cancer Cell Line

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Miganoosh Simonian

2018-01-01

Full Text Available Background: Both microRNAs (miRNAs and long noncoding RNAs (lncRNAs have been shown to have a critical role in the regulation of cellular processes such as cell growth and apoptosis, as well as cancer progression and metastasis. lncRNAs are aberrantly expressed in many diseases including cancer. Although it is well known that miRNAs can target a large number of protein-coding genes, little is known whether miRNAs can also target lncRNAs. In the present study, we determine whether miR-21 can regulate lncRNA cancer susceptibility candidate 2 (CASC2 in colorectal cancer. Materials and Methods: LS174T cells were transfected with locked nucleic acid (LNA-anti-miR-21 and scrambled LNA for 24, 48 and 72 h. The expression of miR-21 and lncCASC2 was evaluated by quantitative reverse transcriptase polymerase chain reaction. Results: However, contrary to what we expected and reported by others, lncCASC2 quantity was significantly reduced in LNA treated LS174T cells compared to the scrambled treated and normal untreated cells (P < 0.05. Conclusion: The interaction of miRNA and lncRNA are not as simple as suggested by other reports. Moreover, it could be complex molecular mechanisms underlying the communication of various noncoding RNA elements.

Characteristics of picoplankton abundances during a Thalassiosira diporocyclus bloom in the Taiwan Bank in late winter.

Science.gov (United States)

Jiang, Xin; Li, Jiajun; Ke, Zhixin; Xiang, Chenhui; Tan, Yehui; Huang, Liangmin

2017-04-15

To understand the variations of picoplankton (Prochlorococcus, Synechococcus, picoeukaryotes, and heterotrophic bacteria) abundances during diatom bloom, the distribution of picoplankton in the Taiwan Bank, South China Sea was investigated using flow cytometry during a Thalassiosira diporocyclus bloom in March 2016. The results indicated an abrupt abundance decrease for Prochlorococcus, Synechococcus, and picoeukaryotes within the bloom area while the abundance of heterotrophic bacteria showed no significant difference between the bloom and non-bloom areas. We found two sub-groups of heterotrophic bacteria: high- and low-nucleic acid content (HNA and LNA) bacteria with HNA dominated in the bloom area whereas LNA dominated in the non-bloom area. Among the picoplankton components, HNA represented the highest (61.1%) carbon biomass in the bloom area while picoeukaryotes represented the highest (37.6%) in the non-bloom area. Our findings implied that heterotrophic bacteria, especially HNA, played an essential role during the diatom bloom. Copyright © 2017 Elsevier Ltd. All rights reserved.

Polymorphisms of the FOXF1 and MHC locus genes in individuals undergoing esophageal acid reflux assessments.

Science.gov (United States)

Lam, C; Liu, W F; Bel, R D; Chan, K; Miller, L; Brown, M C; Chen, Z; Cheng, D; Patel, D; Xu, W; Darling, G E; Liu, G

2017-02-01

Gastroesophageal reflux disease (GERD) may lead to Barrett's esophagus (BE). Previously, a large genome-wide association study found two germline markers to be associated with BE, FOXF1 rs9936833 (C allele) and MHC rs9257809 (A allele). This study evaluated whether these two polymorphisms are associated with gastroesphageal acid reflux as measured by 24-hour pH testing. Patients with acid reflux symptoms referred for esophageal manometry and 24-hour pH monitoring at University Health Network (Toronto, ON) were enrolled. DNA extracted from blood was genotyped using a Taqman Polymerase Chain Reaction (PCR) assay. DeMeester scores of ≥14.7 or prior evidence of reflux esophagitis on endoscopy defined individuals with esophageal acid reflux. Logistic regression analysis, adjusted for clinical risk factors, was used to calculate odds ratios with 95% confidence intervals for each polymorphism in relation to the presence of acid reflux. Of 182 patients, the median age was 50 years and 62% were female; 95 (52%) met the definition of GERD. In the multivariable analysis, both FOXF1 rs9936833 (OR = 1.82; 95%CI: 1.12-2.96; P = 0.02) and MHC rs9257809 (OR = 9.36; 95%CI: 2.92-29.99; P acid reflux. When both polymorphisms were placed in the same model, the adjusted ORs were 2.10 (95%CI: 1.24-3.53; P = 0.005) and 10.95 (95%CI: 3.32-36.09; P acid reflux suggests a potential pathophysiologic mechanism for the role of genetic influences in BE development. © 2016 International Society for Diseases of the Esophagus.

Quantification of the biocontrol agent Trichoderma harzianum with real-time TaqMan PCR and its potential extrapolation to the hyphal biomass.

Science.gov (United States)

López-Mondéjar, Rubén; Antón, Anabel; Raidl, Stefan; Ros, Margarita; Pascual, José Antonio

2010-04-01

The species of the genus Trichoderma are used successfully as biocontrol agents against a wide range of phytopathogenic fungi. Among them, Trichoderma harzianum is especially effective. However, to develop more effective fungal biocontrol strategies in organic substrates and soil, tools for monitoring the control agents are required. Real-time PCR is potentially an effective tool for the quantification of fungi in environmental samples. The aim of this study consisted of the development and application of a real-time PCR-based method to the quantification of T. harzianum, and the extrapolation of these data to fungal biomass values. A set of primers and a TaqMan probe for the ITS region of the fungal genome were designed and tested, and amplification was correlated to biomass measurements obtained with optical microscopy and image analysis, of the hyphal length of the mycelium of the colony. A correlation of 0.76 between ITS copies and biomass was obtained. The extrapolation of the quantity of ITS copies, calculated based on real-time PCR data, into quantities of fungal biomass provides potentially a more accurate value of the quantity of soil fungi. Copyright 2009 Elsevier Ltd. All rights reserved.

Universal detection of phytoplasmas and Xylella spp. by TaqMan singleplex and multiplex real-time PCR with dual priming oligonucleotides.

Directory of Open Access Journals (Sweden)

Takao Ito

Full Text Available Phytoplasmas and Xylella spp. are bacteria that cause many economically important plant diseases worldwide. TaqMan probe-based quantitative real-time polymerase chain reaction (qPCR assays have been utilized to universally detect phytoplasmas or Xylella fastidiosa. To develop a superior universal qPCR method, we used a dual priming oligonucleotide (DPO with two annealing sites as a reverse primer to target the well-conserved bacterial 16S rDNA. The new qPCR assays universally detected various species of phytoplasmas and subspecies of X. fastidiosa as well as Xylella taiwanensis, and generally showed superior threshold cycle values when amplifying specific or non-specific products compared to current universal qPCR assays. The proposed qPCR assays were integrated to develop a multiplex qPCR assay that simultaneously detected phytoplasmas, Xylella spp., and an internal plant DNA positive control within 1 hour. This assay could detect a minimum of ten bacterial cells and was compatible with crude extractions used in the rapid screening of various plants. The amplicons were of sufficient lengths to be directly sequenced for preliminary identification, and the primers could be used in universal conventional PCR assays. Additionally, reverse DPO primers can be utilized to improve other probe-based qPCR assays.

Characterization of Phytophthora nicotianae isolates in southeast Spain and their detection and quantification through a real-time TaqMan PCR.

Science.gov (United States)

Blaya, Josefa; Lacasa, Carmen; Lacasa, Alfredo; Martínez, Victoriano; Santísima-Trinidad, Ana B; Pascual, Jose A; Ros, Margarita

2015-04-01

The soil-borne pathogens Phytophthora nicotianae and P. capsici are the causal agents of root and stem rot of many plant species. Although P. capsici was considered the causal agent in one of the main pepper production areas of Spain to date, evidence of the presence of P. nicotianae was found. We aimed to survey the presence of P. nicotianae and study the variability in its populations in this area in order to improve the management of Tristeza disease. A new specific primer and a TaqMan probe were designed based on the internal transcribed spacer regions of ribosomal DNA to detect and quantify P. nicotianae. Both morphological and molecular analysis showed its presence and confirmed it to be the causal agent of the Phytophthora disease symptoms in the studied area. The genetic characterization among P. nicotianae populations showed a low variability of genetic diversity among the isolates. Only isolates of the A2 mating type were detected. Not only is a specific and early detection of P. nicotianae essential but also the study of genetic variability among isolates for the appropriate management of the disease, above all, in producing areas with favorable conditions for the advance of the disease. © 2014 Society of Chemical Industry.

OVER-EXPRESSION OF GENE ENCODING FATTY ACID METABOLIC ENZYMES IN FISH

Directory of Open Access Journals (Sweden)

Alimuddin Alimuddin

2008-12-01

Full Text Available Eicosapentaenoic acid (EPA, 20:5n-3 and docosahexaenoic acid (DHA, 22:6n-3 have important nutritional benefits in humans. EPA and DHA are mainly derived from fish, but the decline in the stocks of major marine capture fishes could result in these fatty acids being consumed less. Farmed fish could serve as promising sources of EPA and DHA, but they need these fatty acids in their diets. Generation of fish strains that are capable of synthesizing enough amounts of EPA/DHA from the conversion of α-linolenic acid (LNA, 18:3n-3 rich oils can supply a new EPA/DHA source. This may be achieved by over-expression of genes encoding enzymes involved in HUFA biosynthesis. In aquaculture, the successful of this technique would open the possibility to reduce the enrichment of live food with fish oils for marine fish larvae, and to completely substitute fish oils with plant oils without reducing the quality of flesh in terms of EPA and DHA contents. Here, three genes, i.e. Δ6-desaturase-like (OmΔ6FAD, Δ5-desaturase-like (OmΔ5FAD and elongase-like (MELO encoding EPA/DHA metabolic enzymes derived from masu salmon (Oncorhynchus masou were individually transferred into zebrafish (Danio rerio as a model to increase its ability for synthesizing EPA and DHA. Fatty acid analysis showed that EPA content in whole body of the second transgenic fish generation over-expressing OmΔ6FAD gene was 1.4 fold and that of DHA was 2.1 fold higher (P<0.05 than those in non-transgenic fish. The EPA content in whole body of transgenic fish over-expressing OmΔ5FAD gene was 1.21-fold, and that of DHA was 1.24-fold higher (P<0.05 than those in nontransgenic fish. The same patterns were obtained in transgenic fish over-expressing MELO gene. EPA content was increased by 1.30-fold and DHA content by 1.33-fold higher (P<0.05 than those in non-transgenic fish. The results of studies demonstrated that fatty acid content of fish can be enhanced by over

The edible mushroom Laetiporus sulphureus as potential source of natural antioxidants

NARCIS (Netherlands)

Klaus, A.; Kozarski, M.; Niksic, M.; Jakovljevic, D.; Todorovic, N.; Stefanoska, I.; Griensven, van L.J.L.D.

2013-01-01

Hot water extract (LN), partially purified polysaccharides (LP) and hot alkali extracted polysaccharides (LNa) obtained from fruiting bodies of the wild basidiomycete Laetiporus sulphureus were examined for their antioxidant activities. LNa was the most active antioxidant, as shown by the median

[Exploring novel hyperspectral band and key index for leaf nitrogen accumulation in wheat].

Science.gov (United States)

Yao, Xia; Zhu, Yan; Feng, Wei; Tian, Yong-Chao; Cao, Wei-Xing

2009-08-01

The objectives of the present study were to explore new sensitive spectral bands and ratio spectral indices based on precise analysis of ground-based hyperspectral information, and then develop regression model for estimating leaf N accumulation per unit soil area (LNA) in winter wheat (Triticum aestivum L.). Three field experiments were conducted with different N rates and cultivar types in three consecutive growing seasons, and time-course measurements were taken on canopy hyperspectral reflectance and LNA tinder the various treatments. By adopting the method of reduced precise sampling, the detailed ratio spectral indices (RSI) within the range of 350-2 500 nm were constructed, and the quantitative relationships between LNA (gN m(-2)) and RSI (i, j) were analyzed. It was found that several key spectral bands and spectral indices were suitable for estimating LNA in wheat, and the spectral parameter RSI (990, 720) was the most reliable indicator for LNA in wheat. The regression model based on the best RSI was formulated as y = 5.095x - 6.040, with R2 of 0.814. From testing of the derived equations with independent experiment data, the model on RSI (990, 720) had R2 of 0.847 and RRMSE of 24.7%. Thus, it is concluded that the present hyperspectral parameter of RSI (990, 720) and derived regression model can be reliably used for estimating LNA in winter wheat. These results provide the feasible key bands and technical basis for developing the portable instrument of monitoring wheat nitrogen status and for extracting useful spectral information from remote sensing images.

Complete assessment of whole-body n-3 and n-6 PUFA synthesis-secretion kinetics and DHA turnover in a rodent model.

Science.gov (United States)

Metherel, Adam H; Lacombe, R J Scott; Chouinard-Watkins, Raphaël; Hopperton, Kathryn E; Bazinet, Richard P

2018-02-01

Previous assessments of the PUFA biosynthesis pathway have focused on DHA and arachidonic acid synthesis. Here, we determined whole-body synthesis-secretion kinetics for all downstream products of PUFA metabolism, including direct measurements of DHA and n-6 docosapentaenoic acid (DPAn-6, 22:5n-6) turnover, and compared n-6 and n-3 homolog kinetics. We infused labeled α-linolenic acid (ALA, 18:3n-3), linoleic acid (LNA, 18:2n-6), DHA, and DPAn-6 as 2 H 5 -ALA, 13 C 18 -LNA, 13 C 22 -DHA, and 13 C 22 -DPAn-6. Eight 11-week-old Long Evans rats fed a 10% fat diet were infused with the labeled PUFAs over 3 h, and plasma enrichment of labeled products was measured every 30 min. The DHA synthesis-secretion rate (94 ± 34 nmol/day) did not differ from other PUFA products (range, 21.8 ± 4.3 nmol/day to 408 ± 116 nmol/day). Synthesis-secretion rates of n-6 and n-3 PUFA homologs were similar, except 22:4n-6 and DPAn-6 had lower synthesis rates. However, daily turnover from newly synthesized DHA (0.067 ± 0.023%) was 56-fold to 556-fold slower than all other PUFA turnover and was 130-fold slower than that determined directly from the total plasma unesterified DHA pool. In conclusion, n-6 and n-3 PUFA synthesis-secretion kinetics suggest that differences in turnover, not in synthesis-secretion rates, primarily determine PUFA plasma levels. Copyright © 2018 by the American Society for Biochemistry and Molecular Biology, Inc.

Effect of dietary linoleate/alpha-linolenate balance on the brain lipid composition, reproductive outcome and behavior of rats during their prenatal and postnatal development.

Science.gov (United States)

Cheon, S H; Huh, M H; Lee, Y B; Park, J S; Sohn, H S; Chung, C W

2000-11-01

The effect of the dietary linoleate (LA)/alpha-linolenate (LNA) balance during development on the brain lipid composition, reproductive outcome and behavior of rats was studied. Female rats were fed on experimental diets during pregnancy and the resulting pups for 16 weeks. The dietary LA/LNA ratios were 1.07 (LA1), 2.64 (LA2), 4.45 (LA3), 7.68 (LA4) and 10.35 (LA5). The relative content of docosahexaenoate (DHA) in the brain of pups tended to increase with decreasing LA/LNA ratio at 0 and 3 weeks, while the level of DHA was maintained constant at 16 weeks regardless of the dietary LA/LNA ratio. The learning ability was measured at 12 weeks of age, and there was no difference among the groups. In an open field test, the exploratory index was significantly lower in the LA1 group than in the LA2 group. The LA1 group had a smaller litter size and lower survival rate than the other groups. We conclude that if the diet contained appropriate amounts and balance of LA and LNA, it was possible for rats to synthesize an appropriate amount of DHA and have normal behavioral activity without DHA supplementation.

An integrated system for identifying the hidden assassins in traditional medicines containing aristolochic acids

Science.gov (United States)

Wu, Lan; Sun, Wei; Wang, Bo; Zhao, Haiyu; Li, Yaoli; Cai, Shaoqing; Xiang, Li; Zhu, Yingjie; Yao, Hui; Song, Jingyuan; Cheng, Yung-Chi; Chen, Shilin

2015-08-01

Traditional herbal medicines adulterated and contaminated with plant materials from the Aristolochiaceae family, which contain aristolochic acids (AAs), cause aristolochic acid nephropathy. Approximately 256 traditional Chinese patent medicines, containing Aristolochiaceous materials, are still being sold in Chinese markets today. In order to protect consumers from health risks due to AAs, the hidden assassins, efficient methods to differentiate Aristolochiaceous herbs from their putative substitutes need to be established. In this study, 158 Aristolochiaceous samples representing 46 species and four genera as well as 131 non-Aristolochiaceous samples representing 33 species, 20 genera and 12 families were analyzed using DNA barcodes based on the ITS2 and psbA-trnH sequences. Aristolochiaceous materials and their non-Aristolochiaceous substitutes were successfully identified using BLAST1, the nearest distance method and the neighbor-joining (NJ) tree. In addition, based on sequence information of ITS2, we developed a Real-Time PCR assay which successfully identified herbal material from the Aristolochiaceae family. Using Ultra High Performance Liquid Chromatography-Mass Spectrometer (UHPLC-HR-MS), we demonstrated that most representatives from the Aristolochiaceae family contain toxic AAs. Therefore, integrated DNA barcodes, Real-Time PCR assays using TaqMan probes and UHPLC-HR-MS system provides an efficient and reliable authentication system to protect consumers from health risks due to the hidden assassins (AAs).

Geo-Nested Analysis: Mixed-Methods Research with Spatially Dependent Data

NARCIS (Netherlands)

Harbers, I.; Ingram, M.C.

Mixed-methods designs, especially those where cases selected for small-N analysis (SNA) are nested within a large-N analysis (LNA), have become increasingly popular. Yet, since the LNA in this approach assumes that units are independently distributed, such designs are unable to account for spatial

A Low Noise Amplifier for Neural Spike Recording Interfaces

Directory of Open Access Journals (Sweden)

Jesus Ruiz-Amaya

2015-09-01

Full Text Available This paper presents a Low Noise Amplifier (LNA for neural spike recording applications. The proposed topology, based on a capacitive feedback network using a two-stage OTA, efficiently solves the triple trade-off between power, area and noise. Additionally, this work introduces a novel transistor-level synthesis methodology for LNAs tailored for the minimization of their noise efficiency factor under area and noise constraints. The proposed LNA has been implemented in a 130 nm CMOS technology and occupies 0.053 mm-sq. Experimental results show that the LNA offers a noise efficiency factor of 2.16 and an input referred noise of 3.8 μVrms for 1.2 V power supply. It provides a gain of 46 dB over a nominal bandwidth of 192 Hz–7.4 kHz and consumes 1.92 μW. The performance of the proposed LNA has been validated through in vivo experiments with animal models.

The potential of TaqMan Array Cards for detection of multiple biological agents by real-time PCR.

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Phillip A Rachwal

Full Text Available The TaqMan Array Card architecture, normally used for gene expression studies, was evaluated for its potential to detect multiple bacterial agents by real-time PCR. Ten PCR assays targeting five biological agents (Bacillus anthracis, Burkholderia mallei, Burkholderia pseudomallei, Francisella tularensis, and Yersinia pestis were incorporated onto Array Cards. A comparison of PCR performance of each PCR in Array Card and singleplex format was conducted using DNA extracted from pure bacterial cultures. When 100 fg of agent DNA was added to Array Card channels the following levels of agent detection (where at least one agent PCR replicate returned a positive result were observed: Y. pestis 100%, B. mallei & F. tularensis 93%; B. anthracis 71%; B. pseudomallei 43%. For B. mallei & pseudomallei detection the BPM2 PCR, which detects both species, outperformed PCR assays specific to each organism indicating identification of the respective species would not be reproducible at the 100 fg level. Near 100% levels of detection were observed when 100 fg of DNA was added to each PCR in singleplex format with singleplex PCRs also returning sporadic positives at the 10 fg per PCR level. Before evaluating the use of Array Cards for the testing of environmental and clinical sample types, with potential levels of background DNA and PCR inhibitors, users would therefore have to accept a 10-fold reduction in sensitivity of PCR assays on the Array Card format, in order to benefit for the capacity to test multiple samples for multiple agents. A two PCR per agent strategy would allow the testing of 7 samples for the presence of 11 biological agents or 3 samples for 23 biological agents per card (with negative control channels.

Development of a Taqman real-time PCR assay for rapid detection and quantification of Vibrio tapetis in extrapallial fluids of clams

Directory of Open Access Journals (Sweden)

Adeline Bidault

2015-12-01

Full Text Available The Gram-negative bacterium Vibrio tapetis is known as the causative agent of Brown Ring Disease (BRD in the Manila clam Venerupis (=Ruditapes philippinarum. This bivalve is the second most important species produced in aquaculture and has a high commercial value. In spite of the development of several molecular methods, no survey has been yet achieved to rapidly quantify the bacterium in the clam. In this study, we developed a Taqman real-time PCR assay targeting virB4 gene for accurate and quantitative identification of V. tapetis strains pathogenic to clams. Sensitivity and reproducibility of the method were assessed using either filtered sea water or extrapallial fluids of clam injected with the CECT4600T V. tapetis strain. Quantification curves of V. tapetis strain seeded in filtered seawater (FSW or extrapallial fluids (EF samples were equivalent showing reliable qPCR efficacies. With this protocol, we were able to specifically detect V. tapetis strains down to 1.125 101 bacteria per mL of EF or FSW, taking into account the dilution factor used for appropriate template DNA preparation. This qPCR assay allowed us to monitor V. tapetis load both experimentally or naturally infected Manila clams. This technique will be particularly useful for monitoring the kinetics of massive infections by V. tapetis and for designing appropriate control measures for aquaculture purposes.

Sensitive and specific detection of potentially allergenic almond (Prunus dulcis) in complex food matrices by Taqman real-time polymerase chain reaction in comparison to commercially available protein-based enzyme-linked immunosorbent assay

International Nuclear Information System (INIS)

Roeder, Martin; Vieths, Stefan; Holzhauser, Thomas

2011-01-01

Currently, causative immunotherapies are lacking in food allergy. The only option to prevent allergic reactions in susceptible individuals is to strictly avoid the offending food. Thus, reliable labelling of allergenic constituents is of major importance, but can only be achieved if appropriate specific and sensitive detection techniques for foods with allergenic potential are available. Almond is an allergenic food that requires mandatory labelling on prepackaged foods and belongs to the genus Prunus. Species of this genus are phylogenetically closely related. We observed commercially available almond specific ELISA being highly cross-reactive with other foods of the Prunoideae family, resulting in a false-positive detection of up to 500,000 mg kg -1 almond. Previously published PCR methods were reported to be cross-reactive with false positive results >1200 mg kg -1 . We describe the development of a novel almond specific real-time PCR, based on mutated mismatch primers and sequence specific Taqman probe detection, in comparison with two quantitative commercially available ELISA. PCR sensitivity was investigated with chocolate, chocolate coating and cookies spiked between 5 and 100,000 mg kg -1 almond. In all matrices almond was reproducibly detected by real-time PCR at the lowest spike level of 5 mg kg -1 . Further, between 100 and 100,000 mg kg -1 spiked almond, the method featured good correlation between quantified copy numbers and the amount of spiked almond. Within this range a similar relation between detectable signal and amount of almond was observed for both PCR and ELISA. In contrast to ELISA the Taqman real-time PCR method was highly specific in 59 food items with negligible cross-reactivity for a very limited number of Prunoideae foods. The real-time PCR analysis of 24 retail samples was in concordance with ELISA results: 21% (n = 5) contained undeclared almond. This is the first completely disclosed real-time PCR method for a specific and

Inhibition of miR-15 Protects Against Cardiac Ischemic Injury

Science.gov (United States)

Hullinger, Thomas G.; Montgomery, Rusty L.; Seto, Anita G.; Dickinson, Brent A.; Semus, Hillary M.; Lynch, Joshua M.; Dalby, Christina M.; Robinson, Kathryn; Stack, Christianna; Latimer, Paul A.; Hare, Joshua M.; Olson, Eric N.; van Rooij, Eva

2012-01-01

Rationale Myocardial infarction (MI) is a leading cause of death worldwide. Because endogenous cardiac repair mechanisms are not sufficient for meaningful tissue regeneration, MI results in loss of cardiac tissue and detrimental remodeling events. MicroRNAs (miRNAs) are small, noncoding RNAs that regulate gene expression in a sequence dependent manner. Our previous data indicate that miRNAs are dysregulated in response to ischemic injury of the heart and actively contribute to cardiac remodeling after MI. Objective This study was designed to determine whether miRNAs are dysregulated on ischemic damage in porcine cardiac tissues and whether locked nucleic acid (LNA)-modified anti-miR chemistries can target cardiac expressed miRNAs to therapeutically inhibit miR-15 on ischemic injury. Methods and Results Our data indicate that the miR-15 family, which includes 6 closely related miRNAs, is regulated in the infarcted region of the heart in response to ischemia-reperfusion injury in mice and pigs. LNA-modified chemistries can effectively silence miR-15 family members in vitro and render cardiomyocytes resistant to hypoxia-induced cardiomyocyte cell death. Correspondingly, systemic delivery of miR-15 anti-miRs dose-dependently represses miR-15 in cardiac tissue of both mice and pigs, whereas therapeutic targeting of miR-15 in mice reduces infarct size and cardiac remodeling and enhances cardiac function in response to MI. Conclusions Oligonucleotide-based therapies using LNA-modified chemistries for modulating cardiac miRNAs in the setting of heart disease are efficacious and validate miR-15 as a potential therapeutic target for the manipulation of cardiac remodeling and function in the setting of ischemic injury. PMID:22052914

Long-time analytic approximation of large stochastic oscillators: Simulation, analysis and inference.

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Giorgos Minas

2017-07-01

Full Text Available In order to analyse large complex stochastic dynamical models such as those studied in systems biology there is currently a great need for both analytical tools and also algorithms for accurate and fast simulation and estimation. We present a new stochastic approximation of biological oscillators that addresses these needs. Our method, called phase-corrected LNA (pcLNA overcomes the main limitations of the standard Linear Noise Approximation (LNA to remain uniformly accurate for long times, still maintaining the speed and analytically tractability of the LNA. As part of this, we develop analytical expressions for key probability distributions and associated quantities, such as the Fisher Information Matrix and Kullback-Leibler divergence and we introduce a new approach to system-global sensitivity analysis. We also present algorithms for statistical inference and for long-term simulation of oscillating systems that are shown to be as accurate but much faster than leaping algorithms and algorithms for integration of diffusion equations. Stochastic versions of published models of the circadian clock and NF-κB system are used to illustrate our results.

Rapid and Quantitative Detection of Leifsonia xyli subsp. xyli in Sugarcane Stalk Juice Using a Real-Time Fluorescent (TaqMan PCR Assay

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Hua-Ying Fu

2016-01-01

Full Text Available Ratoon stunting disease (RSD of sugarcane, one of the most important diseases seriously affecting the productivity of sugarcane crops, was caused by the bacterial agent Leifsonia xyli subsp. xyli (Lxx. A TaqMan probe-based real-time quantitative polymerase chain reaction (qPCR assay was established in this study for the quantification of Lxx detection in sugarcane stalk juice. A pair of PCR primers (Pat1-QF/Pat1-QR and a fluorogenic probe (Pat1-QP targeting the Part1 gene of Lxx were used for the qPCR assay. The assay had a detection limit of 100 copies of plasmid DNA and 100 fg of Lxx genomic DNA, which was 100-fold more sensitive than the conventional PCR. Fifty (28.7% of 174 stalk juice samples from two field trials were tested to be positive by qPCR assay, whereas, by conventional PCR, only 12.1% (21/174 were tested to be positive with a published primer pair CxxITSf#5/CxxITSr#5 and 15.5% (27/174 were tested to be positive with a newly designed primer pair Pat1-F2/Pat1-R2. The new qPCR assay can be used as an alternative to current diagnostic methods for Lxx, especially when dealing with certificating a large number of healthy cane seedlings and determining disease incidence accurately in commercial fields.

One window-period donation in two years of individual donor-nucleic acid test screening for hepatitis B, hepatitis C and human immunodeficiency virus

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Jose Eduardo Levi

2013-06-01

Full Text Available Objective: To describe general data on nucleic acid/serology testing and report the first hepatitis B-nucleic acid testing yield case of an immunized donor in Brazil. Methods: A total of 24,441 donations collected in 2010 and 2011 were submitted to individual nucleic acid testing for hepatitis B, hepatitis C and human immunodeficiency virus using the TaqMan® MPX kit (Roche on the Cobas s201 platform, in addition to routine screening for serological markers. Nucleic acid testing-reactive donations were further evaluated by real-time polymerase chain reaction using Cobas AmpliPrep/Cobas TaqMan hepatitis B virus, hepatitis C virus and human immunodeficiency virus tests. Results: Thirty-two donations were reactive by nucleic acid testing, 31 were also serologically reactive and one first-time donor was identified as having hepatitis B in the window period. Follow-up samples showed increasing titers of anti-HBs rising from 19 UI/mL in the index donation to 109 IU/mL seven months later attributable to his vaccination history. Curiously, this donor was never reactive for HbsAg nor for anti-HBc. In the yield donation, he was concomitantly reactive for syphilis (enzyme immunoassay and fluorescent treponemal antibody-absorption; venereal disease research laboratory non-reactive. Overall, six donors (0.02% were characterized as occult hepatitis B. A total of 35% of the confirmed (recombinant immunoblot assay positive hepatitis C donations were nucleic acid testing non-reactive and no human immunodeficiency virus "elite controller" was identified. Conclusion: The yield rate (1:24,441; 95% confidence interval: 1:9,537 - 1:89,717 contrasts to the North American rate (1:410,540 donations and strongly advocates the adoption of nucleic acid testing for hepatitis B in Brazil despite the increasing rate of anti-HBs reactive subjects due to the successful immunization program.

Dynamics of anion exchange of lanthanides in aqueous-organic complexing media

International Nuclear Information System (INIS)

Sheveleva, I.V.; Bogatyrev, I.O.

1987-01-01

Effect of organic solvents (ethanol, acetone, acetonitrile) on change in kinetic parameters of the anion exchange process (anion-exchange column chromatography) of r.e.e. (europium and gadolinium) in complexing nitric acid media has been studied. It is established that complex LnA 4 anion is the only sorbing form of europium and gadolinium on anionite. When the organic component content of the solution being the same, the dynamic parameters of lanthanide exchange have higher values in aqueous-acetonitrile and aqueous-acetone media in comparison with aqueous-enthanol solutions of nitric acid. Lesser mobility of complex lanthanide anions in aqueous-alcoholic solutions can be explained by stronger solvation in the presence of solvents with higher acceptor properties

Detection of viable Salmonella in ice cream by TaqMan real-time polymerase chain reaction assay combining propidium monoazide

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Yuexia Wang

2015-09-01

Full Text Available Real-time polymerase chain reaction (PCR allows rapid detection of Salmonella in frozen dairy products, but it might cause a false positive detection result because it might amplify DNA from dead target cells as well. In this study, Salmonella-free frozen ice cream was initially inoculated with heat-killed Salmonella Typhimurium cells and stored at −18°C. Bacterial DNA extracted from the sample was amplified using TaqMan probe-based real-time PCR targeting the invA gene. Our results indicated that DNA from the dead cells remained stable in frozen ice cream for at least 20 days, and could produce fluorescence signal for real-time PCR as well. To overcome this limitation, propidium monoazide (PMA was combined with real-time PCR. PMA treatment can effectively prevent PCR amplification from heat-killed Salmonella cells in frozen ice cream. The PMA real-time PCR assay can selectively detect viable Salmonella at as low as 103 CFU/mL. Combining 18 hours of pre-enrichment with the assay allows for the detection of viable Salmonella at 100 CFU/mL and avoiding the false-positive result of dead cells. The PMA real-time PCR assay provides an alternative specifically for detection of viable Salmonella in ice cream. However, when the PMA real-time PCR assay was evaluated in ice cream subjected to frozen storage, it obviously underestimated the contamination situation of viable Salmonella, which might lead to a false negative result. According to this result, the use of enrichment prior to PMA real-time PCR analysis remains as the more appropriate approach.

Detection of viable Salmonella in ice cream by TaqMan real-time polymerase chain reaction assay combining propidium monoazide.

Science.gov (United States)

Wang, Yuexia; Yang, Ming; Liu, Shuchun; Chen, Wanyi; Suo, Biao

2015-09-01

Real-time polymerase chain reaction (PCR) allows rapid detection of Salmonella in frozen dairy products, but it might cause a false positive detection result because it might amplify DNA from dead target cells as well. In this study, Salmonella-free frozen ice cream was initially inoculated with heat-killed Salmonella Typhimurium cells and stored at -18°C. Bacterial DNA extracted from the sample was amplified using TaqMan probe-based real-time PCR targeting the invA gene. Our results indicated that DNA from the dead cells remained stable in frozen ice cream for at least 20 days, and could produce fluorescence signal for real-time PCR as well. To overcome this limitation, propidium monoazide (PMA) was combined with real-time PCR. PMA treatment can effectively prevent PCR amplification from heat-killed Salmonella cells in frozen ice cream. The PMA real-time PCR assay can selectively detect viable Salmonella at as low as 10 3  CFU/mL. Combining 18 hours of pre-enrichment with the assay allows for the detection of viable Salmonella at 10 0  CFU/mL and avoiding the false-positive result of dead cells. The PMA real-time PCR assay provides an alternative specifically for detection of viable Salmonella in ice cream. However, when the PMA real-time PCR assay was evaluated in ice cream subjected to frozen storage, it obviously underestimated the contamination situation of viable Salmonella, which might lead to a false negative result. According to this result, the use of enrichment prior to PMA real-time PCR analysis remains as the more appropriate approach. Copyright © 2015. Published by Elsevier B.V.

Op-amp based low noise amplifier for magnetic particle spectroscopy

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Malhotra Ankit

2017-09-01

Full Text Available Magnetic particle spectrometry (MPS is a novel technique used to measure the magnetization response of superparamagnetic iron oxide nanoparticles (SPIONs. Therefore, it is one of the most important tools for the characterization of the SPIONs for imaging modalities such as magnetic particle imaging (MPI and Magnetic Resonance Imaging (MRI. In MPS, change in the particle magnetization induces a voltage in a dedicated receive coil. The amplitude of the signal can be very low (ranging from a few nV to 100 μV depending upon the concentration of the nanoparticles. Hence, the received signal needs to be amplified with a low noise amplifier (LNA. LNA’s paramount task is to amplify the received signal while keeping the noise induced by its own circuitry minimum. In the current research, we purpose modeling, design, and development of a prototyped LNA for MPS. The designed prototype LNA is based on the parallelization technique of Op-amps. The prototyped LNA consists of 16 Op-amps in parallel and is manufactured on a printed circuit board (PCB, with a size of 110.38 mm × 59.46 mm and 234 components. The input noise of the amplifier is approx. 546 pV/√Hz with a noise figure (NF of approx. 1.4 dB with a receive coil termination. Furthermore, a comparison between the prototyped LNA and a commercially available amplifier is shown.

Polymorphisms in Genes Involved in Fatty Acid β-Oxidation Interact with Dietary Fat Intakes to Modulate the Plasma TG Response to a Fish Oil Supplementation

Science.gov (United States)

Bouchard-Mercier, Annie; Rudkowska, Iwona; Lemieux, Simone; Couture, Patrick; Vohl, Marie-Claude

2014-01-01

A large inter-individual variability in the plasma triglyceride (TG) response to an omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation has been observed. The objective was to examine gene-diet interaction effects on the plasma TG response after a fish oil supplementation, between single-nucleotide polymorphisms (SNPs) within genes involved in fatty acid β-oxidation and dietary fat intakes. Two hundred and eight (208) participants were recruited in the greater Quebec City area. The participants completed a six-week fish oil supplementation (5 g fish oil/day: 1.9–2.2 g EPA and 1.1 g DHA). Dietary fat intakes were measured using three-day food records. SNPs within RXRA, CPT1A, ACADVL, ACAA2, ABCD2, ACOX1 and ACAA1 genes were genotyped using TAQMAN methodology. Gene-diet interaction effects on the plasma TG response were observed for SNPs within RXRA (rs11185660, rs10881576 and rs12339187) and ACOX1 (rs17583163) genes. For rs11185660, fold changes in RXRA gene expression levels were different depending on SFA intakes for homozygotes T/T. Gene-diet interaction effects of SNPs within genes involved in fatty acid β-oxidation and dietary fat intakes may be important in understanding the inter-individual variability in plasma TG levels and in the plasma TG response to a fish oil supplementation. PMID:24647074

Polymorphisms in Genes Involved in Fatty Acid β-Oxidation Interact with Dietary Fat Intakes to Modulate the Plasma TG Response to a Fish Oil Supplementation

Directory of Open Access Journals (Sweden)

Annie Bouchard-Mercier

2014-03-01

Full Text Available A large inter-individual variability in the plasma triglyceride (TG response to an omega-3 polyunsaturated fatty acid (n-3 PUFA supplementation has been observed. The objective was to examine gene-diet interaction effects on the plasma TG response after a fish oil supplementation, between single-nucleotide polymorphisms (SNPs within genes involved in fatty acid β-oxidation and dietary fat intakes. Two hundred and eight (208 participants were recruited in the greater Quebec City area. The participants completed a six-week fish oil supplementation (5 g fish oil/day: 1.9–2.2 g EPA and 1.1 g DHA. Dietary fat intakes were measured using three-day food records. SNPs within RXRA, CPT1A, ACADVL, ACAA2, ABCD2, ACOX1 and ACAA1 genes were genotyped using TAQMAN methodology. Gene-diet interaction effects on the plasma TG response were observed for SNPs within RXRA (rs11185660, rs10881576 and rs12339187 and ACOX1 (rs17583163 genes. For rs11185660, fold changes in RXRA gene expression levels were different depending on SFA intakes for homozygotes T/T. Gene-diet interaction effects of SNPs within genes involved in fatty acid β-oxidation and dietary fat intakes may be important in understanding the inter-individual variability in plasma TG levels and in the plasma TG response to a fish oil supplementation.

Molecular detection of foodborne pathogens

DEFF Research Database (Denmark)

Josefsen, Mathilde Hartmann

Microbiological Methods (NordVal) in comparative and collaborative trials, and was approved for detection of Campylobacter in chicken neck skin, cloacal swab and boot swab samples. A comparison study on probe chemistries for real-time PCR was performed on locked nucleic acid (LNA), minor groove binder (MGB...... of the optimization strategy were observed from increasing 1) the sampling volume from the pre-enrichment, 2) the paramagnetic particles applied in the DNA extraction procedure, and 3) the amount of DNA template in the PCR. This method was subsequently validated according to the recommendations of NordVal...

Sensitive and specific detection of potentially allergenic almond (Prunus dulcis) in complex food matrices by Taqman real-time polymerase chain reaction in comparison to commercially available protein-based enzyme-linked immunosorbent assay

Energy Technology Data Exchange (ETDEWEB)

Roeder, Martin; Vieths, Stefan [Division of Allergology, Paul-Ehrlich-Institut, Paul-Ehrlich-Strasse 51-59, 63225 Langen (Germany); Holzhauser, Thomas, E-mail: holth@pei.de [Division of Allergology, Paul-Ehrlich-Institut, Paul-Ehrlich-Strasse 51-59, 63225 Langen (Germany)

2011-01-24

Currently, causative immunotherapies are lacking in food allergy. The only option to prevent allergic reactions in susceptible individuals is to strictly avoid the offending food. Thus, reliable labelling of allergenic constituents is of major importance, but can only be achieved if appropriate specific and sensitive detection techniques for foods with allergenic potential are available. Almond is an allergenic food that requires mandatory labelling on prepackaged foods and belongs to the genus Prunus. Species of this genus are phylogenetically closely related. We observed commercially available almond specific ELISA being highly cross-reactive with other foods of the Prunoideae family, resulting in a false-positive detection of up to 500,000 mg kg{sup -1} almond. Previously published PCR methods were reported to be cross-reactive with false positive results >1200 mg kg{sup -1}. We describe the development of a novel almond specific real-time PCR, based on mutated mismatch primers and sequence specific Taqman probe detection, in comparison with two quantitative commercially available ELISA. PCR sensitivity was investigated with chocolate, chocolate coating and cookies spiked between 5 and 100,000 mg kg{sup -1} almond. In all matrices almond was reproducibly detected by real-time PCR at the lowest spike level of 5 mg kg{sup -1}. Further, between 100 and 100,000 mg kg{sup -1} spiked almond, the method featured good correlation between quantified copy numbers and the amount of spiked almond. Within this range a similar relation between detectable signal and amount of almond was observed for both PCR and ELISA. In contrast to ELISA the Taqman real-time PCR method was highly specific in 59 food items with negligible cross-reactivity for a very limited number of Prunoideae foods. The real-time PCR analysis of 24 retail samples was in concordance with ELISA results: 21% (n = 5) contained undeclared almond. This is the first completely disclosed real-time PCR method for a

A 540-[Formula: see text] Duty Controlled RSSI With Current Reusing Technique for Human Body Communication.

Science.gov (United States)

Jang, Jaeeun; Lee, Yongsu; Cho, Hyunwoo; Yoo, Hoi-Jun

2016-08-01

An ultra-low-power duty controlled received signal strength indicator (RSSI) is implemented for human body communication (HBC) in 180 nm CMOS technology under 1.5 V supply. The proposed RSSI adopted 3 following key features for low-power consumption; 1) current reusing technique (CR-RSSI) with replica bias circuit and calibration unit, 2) duty controller, and 3) reconfigurable gm-boosting LNA. The CR-RSSI utilizes stacked amplifier-rectifier-cell (AR-cell) to reuse the supply current of each blocks. As a result, the power consumption becomes 540 [Formula: see text] with +/-2 dB accuracy and 75 dB dynamic range. The replica bias circuit and calibration unit are adopted to increase the reliability of CR-RSSI. In addition, the duty controller turns off the RSSI when it is not required, and this function leads 70% power reduction. At last, the gm-boosting reconfigurable LNA can adaptively vary its noise and linearity performance with respect to input signal strength. Fro current reusing technique m this feature, we achieve 62% power reduction in the LNA. Thanks to these schemes, compared to the previous works, we can save 70% of power in RSSI and LNA.

TaqMan real-time polymerase chain reaction for detection of Ophidiomyces ophiodiicola, the fungus associated with snake fungal disease.

Science.gov (United States)

Bohuski, Elizabeth; Lorch, Jeffrey M; Griffin, Kathryn M; Blehert, David S

2015-04-15

Fungal skin infections associated with Ophidiomyces ophiodiicola, a member of the Chrysosporium anamorph of Nannizziopsis vriesii (CANV) complex, have been linked to an increasing number of cases of snake fungal disease (SFD) in captive snakes around the world and in wild snake populations in eastern North America. The emergence of SFD in both captive and wild situations has led to an increased need for tools to better diagnose and study the disease. We developed two TaqMan real-time polymerase chain reaction (PCR) assays to rapidly detect O. ophiodiicola in clinical samples. One assay targets the internal transcribed spacer region (ITS) of the fungal genome while the other targets the more variable intergenic spacer region (IGS). The PCR assays were qualified using skin samples collected from 50 snakes for which O. ophiodiicola had been previously detected by culture, 20 snakes with gross skin lesions suggestive of SFD but which were culture-negative for O. ophiodiicola, and 16 snakes with no clinical signs of infection. Both assays performed equivalently and proved to be more sensitive than traditional culture methods, detecting O. ophiodiicola in 98% of the culture-positive samples and in 40% of the culture-negative snakes that had clinical signs of SFD. In addition, the assays did not cross-react with a panel of 28 fungal species that are closely related to O. ophiodiicola or that commonly occur on the skin of snakes. The assays did, however, indicate that some asymptomatic snakes (~6%) may harbor low levels of the fungus, and that PCR should be paired with histology when a definitive diagnosis is required. These assays represent the first published methods to detect O. ophiodiicola by real-time PCR. The ITS assay has great utility for assisting with SFD diagnoses whereas the IGS assay offers a valuable tool for research-based applications.

A passive dual-circulator based transmit/receive switch for use with reflection resonators in pulse EPR

Science.gov (United States)

Subramanian, V. S.; Epel, Boris; Mailer, Colin; Halpern, Howard J.

2009-01-01

In order to protect the low noise amplifier (LNA) in the receive arm of a pulsed 250 MHz EPR bridge, it is necessary to install as much isolation as possible between the power exciting the spin system and the LNA when high power is present in the receive arm of the bridge, while allowing the voltage induced by the magnetization in the spin sample to be passed undistorted and undiminished to the LNA once power is reduced below the level that can cause a LNA damage. We discuss a combination of techniques to accomplish this involving the power-routing circulator in the bridge, a second circulator acting as an isolator with passive shunt PIN diodes immediately following the second circulator. The low resistance of the forward biased PIN diode passively generates an impedance mismatch at the second circulator output port during the high power excitation pulse and resonator ring down. The mismatch reflects the high power to the remaining port of the second circulator, dumping it into a system impedance matched load. Only when the power diminishes below the diode conduction threshold will the resistance of the PIN diode rise to a value much higher than the system impedance. This brings the device into conduction mode. We find that the present design passively limits the output power to 14 dBm independent of the input power. For high input power levels the isolation may exceed 60 dB. This level of isolation is sufficient to fully protect the LNA of pulse EPR bridge. PMID:20052312

Sensitive and specific detection of potentially allergenic almond (Prunus dulcis) in complex food matrices by Taqman(®) real-time polymerase chain reaction in comparison to commercially available protein-based enzyme-linked immunosorbent assay.

Science.gov (United States)

Röder, Martin; Vieths, Stefan; Holzhauser, Thomas

2011-01-24

Currently, causative immunotherapies are lacking in food allergy. The only option to prevent allergic reactions in susceptible individuals is to strictly avoid the offending food. Thus, reliable labelling of allergenic constituents is of major importance, but can only be achieved if appropriate specific and sensitive detection techniques for foods with allergenic potential are available. Almond is an allergenic food that requires mandatory labelling on prepackaged foods and belongs to the genus Prunus. Species of this genus are phylogenetically closely related. We observed commercially available almond specific ELISA being highly cross-reactive with other foods of the Prunoideae family, resulting in a false-positive detection of up to 500,000 mg kg(-1) almond. Previously published PCR methods were reported to be cross-reactive with false positive results >1200 mg kg(-1). We describe the development of a novel almond specific real-time PCR, based on mutated mismatch primers and sequence specific Taqman(®) probe detection, in comparison with two quantitative commercially available ELISA. PCR sensitivity was investigated with chocolate, chocolate coating and cookies spiked between 5 and 100,000 mg kg(-1) almond. In all matrices almond was reproducibly detected by real-time PCR at the lowest spike level of 5 mg kg(-1). Further, between 100 and 100,000 mg kg(-1) spiked almond, the method featured good correlation between quantified copy numbers and the amount of spiked almond. Within this range a similar relation between detectable signal and amount of almond was observed for both PCR and ELISA. In contrast to ELISA the Taqman(®) real-time PCR method was highly specific in 59 food items with negligible cross-reactivity for a very limited number of Prunoideae foods. The real-time PCR analysis of 24 retail samples was in concordance with ELISA results: 21% (n=5) contained undeclared almond. This is the first completely disclosed real-time PCR method for a specific and

Novel matched amplifiers with low noise positive feedback. Part II: Resistive-capacitive feedback

Science.gov (United States)

Bruck, Y.; Zakharenko, V.

2010-02-01

This article is a continuation of consideration for an amplifier with resistive positive feedback (RPF) (Bruck (2008), 'Novel Matched LNA with Low Noise Positive Feedback. Part 1: General Features and Resistive Feedback', International Journal of Electronics, 95, 441-456). We propose here new configuration schematics of a transformer-less selective LNA with resistive-capacitive positive feedback (RCPF). A circuit of an amplifier with a transistor connected into a circuit with a common base (CB) configuration is analysed in detail. RCPF and RPF circuits are compared. It is shown that the LNA RCPF provides any pass-band, a good level of input and output matching, a minimum noise temperature which is significantly lower than that of the LNA RPF, a rather high linearity, and stability of amplification. The simulation results and some experimental data for the amplifiers intended for use in the LOFAR radiotelescope (Konovalenko et al. (2003), 'Thirty Element Array Antenna as a Prototype of a Huge Low-Frequency Radio Telescope,' Experimental Astronomy, 16, 149-164; Konovalenko (2007), 'Ukrainian Contribution to LOFAR', A scientific workshop, organised by LOFAR/ASTRON' Emmen, Netherlands, 23-27. http://www.lofar.org/workshop) are given. It is assumed that such devices are of a special interest for high-frequency integral circuits (IC).

Omega-6/omega-3 fatty acid intake of children and older adults in the U.S.: dietary intake in comparison to current dietary recommendations and the Healthy Eating Index.

Science.gov (United States)

Sheppard, Kelly W; Cheatham, Carol L

2018-03-09

Omega-6 and omega-3 fatty acids (FAs) and their ratio have been shown to affect cognitive function in children and older adults. With these analyses, we aimed to describe omega-6 and omega-3 FA intake among children and older adults in light of FA intake recommendations and with consideration of overall diet. Data were merged from two cross-sectional studies with 219 children 7 to 12 years old and one longitudinal study with 133 adults 65 to 79 years old. Demographic data, anthropometric data, and Healthy Eating Index scores were used to study relations among the omega-6 to omega-3 FA ratio and age, education, body mass index, and diet quality. FA intake, demographic, and anthropometric data were examined using partial correlations, t-tests, and analysis of variance. Most children and adults consumed at least the recommended amount of alpha-linolenic acid (LNA; omega-3) for their age and gender without consuming high amounts of linoleic acid (LA; omega-6), but did not consume sufficient eicosapentaenoic acid (EPA; omega-) and docosahexaenoic acid (DHA; omega-3). The average omega-6 to omega-3 ratios in both groups were lower than previously reported. Eating lower ratios was associated with healthier diets and consuming adequate amounts of several other nutrients. No demographic or anthropometric variables were related to FA intake in children. Adults with a college degree had significantly lower ratios than those without a college degree. American children and older adults are able to consume more balanced omega-6 to omega-3 ratios than has been indicated by commodity data. However, very few American children met even the lowest recommendations for EPA and DHA intake. Research is needed to clarify recommendations for the optimal ratio across development, which may aid in increasing EPA and DHA intake and improving health outcomes in the United States. ClinicalTrials.gov NCT02199808 13 July 2014, NCT01823419 (retrospectively registered) 20 March 2013, and NCT

Legislation for nuclear disaster

International Nuclear Information System (INIS)

Nagata, Shozo

2012-01-01

Fukushima nuclear disaster accident clarified problems on nuclear-related legislation and its application. Legislation for nuclear disaster (LNA) could not respond to severe accident because assumed size of accident was not enough. After emergency event corresponding to the article 15 of LNA, was reported by the operator, more than two hours passed by the issuance of Emergency State Declaration. Off-site center could not work at all. This article reviewed outline of LNA and introduced discussion on the reform of legislation and its application. Reform discussion should be focused on swift and effective response readiness to emergency: 1) operator's substantial nuclear emergency drilling, (2) reinforcement of government's headquarters for emergency response, (3) after nuclear emergency, government's headquarters remained to enhance resident's safety from radiation hazard and (4) enactment of nuclear emergency preparedness guidelines for local communities. (T. Tanaka)

TaqMan探针荧光定量PCR检测花生油中掺入棕榈油的研究%Determination of palm oil adulterated in peanut oil with the TaqMan probe -based RT- PCR method

Institute of Scientific and Technical Information of China (English)

周慧; 梁宇斌; 吴苏喜; 李晓明; 裴伟; 杨涛

2011-01-01

The method of Real - time fluorescence quantitative polymerase chain reaction ( RT - PCR) with TaqMan fluorescent probe was chosen to fast detect the amount of palm oil mixed in peanut oil. MT3 - B gene of palm was selected as target gene to detect palm oil from peanut oil. The primers of MT3 - B and TaqMan probe were designed, MT3 - B gene reconstructed plasmid was built as absolute quantitative criteria for quantitative RT - PCR to establish standard curve. Peanut oil blended with 1% -40% concentration gradient palm oil was extracted DNA to test palm content by RT - PCR. The result showed that the correlation coefficient (R1) of standard curve with logarithmic linear regression analysis was 0.996. When the adulteration of palm oil in peanut oil reached 5% volume, MT3 - B gene of 17.431 copies per milli-liter of mixed oil could be detected . The method showed good sensitivity, specificity and repeatability.%根据棕榈内源基因MT3 -B设计引物和TaqMan探针,采用基因重组技术构建用于检测棕榈基因MT3 -B的重组质粒作为绝对定量标准品,建立标准曲线,对花生油中掺入棕榈油1% ～40%梯度混合油品提取DNA进行棕榈成分定量检测.结果表明,重组质粒标准品荧光定量标准曲线对数线性回归分析相关系数(R2)为0.996;花生油中掺入棕榈油达到5%时,可检出每亳升混合油品中棕榈MT3 -B基因17.431 copies,检测的重复性和特异性好.

Accurate Digital Polymerase Chain Reaction Quantification of Challenging Samples Applying Inhibitor-Tolerant DNA Polymerases.

Science.gov (United States)

Sidstedt, Maja; Romsos, Erica L; Hedell, Ronny; Ansell, Ricky; Steffen, Carolyn R; Vallone, Peter M; Rådström, Peter; Hedman, Johannes

2017-02-07

Digital PCR (dPCR) enables absolute quantification of nucleic acids by partitioning of the sample into hundreds or thousands of minute reactions. By assuming a Poisson distribution for the number of DNA fragments present in each chamber, the DNA concentration is determined without the need for a standard curve. However, when analyzing nucleic acids from complex matrixes such as soil and blood, the dPCR quantification can be biased due to the presence of inhibitory compounds. In this study, we evaluated the impact of varying the DNA polymerase in chamber-based dPCR for both pure and impure samples using the common PCR inhibitor humic acid (HA) as a model. We compared the TaqMan Universal PCR Master Mix with two alternative DNA polymerases: ExTaq HS and Immolase. By using Bayesian modeling, we show that there is no difference among the tested DNA polymerases in terms of accuracy of absolute quantification for pure template samples, i.e., without HA present. For samples containing HA, there were great differences in performance: the TaqMan Universal PCR Master Mix failed to correctly quantify DNA with more than 13 pg/nL HA, whereas Immolase (1 U) could handle up to 375 pg/nL HA. Furthermore, we found that BSA had a moderate positive effect for the TaqMan Universal PCR Master Mix, enabling accurate quantification for 25 pg/nL HA. Increasing the amount of DNA polymerase from 1 to 5 U had a strong effect for ExTaq HS, elevating HA-tolerance four times. We also show that the average Cq values of positive reactions may be used as a measure of inhibition effects, e.g., to determine whether or not a dPCR quantification result is reliable. The statistical models developed to objectively analyze the data may also be applied in quality control. We conclude that the choice of DNA polymerase in dPCR is crucial for the accuracy of quantification when analyzing challenging samples.

Partial baroreceptor dysfunction and low plasma nitric oxide bioavailability as determinants of salt-sensitive hypertension: a reverse translational rat study

Energy Technology Data Exchange (ETDEWEB)

Rodríguez-Pérez, A.S.; López-Rodríguez, J.F.; Calvo-Turrubiartes, M.Z. [Integrative Physiology Laboratory, Department of Physiology and Biophysics, San Luis Potosí (Mexico); Saavedra-Alanís, V.M. [Molecular Biology Laboratory, Department of Biochemistry, San Luis Potosí (Mexico); Llamazares-Azuara, L. [Autonomous University of San Luis Potosí, Renal Laboratory, Faculty of Medicine, San Luis Potosí (Mexico); Rodríguez-Martínez, M. [Integrative Physiology Laboratory, Department of Physiology and Biophysics, San Luis Potosí (Mexico)

2013-10-02

This study determined whether clinical salt-sensitive hypertension (cSSHT) results from the interaction between partial arterial baroreceptor impairment and a high-sodium (HNa) diet. In three series (S-I, S-II, S-III), mean arterial pressure (MAP) of conscious male Wistar ChR003 rats was measured once before (pdMAP) and twice after either sham (SHM) or bilateral aortic denervation (AD), following 7 days on a low-sodium (LNa) diet (LNaMAP) and then 21 days on a HNa diet (HNaMAP). The roles of plasma nitric oxide bioavailability (pNOB), renal medullary superoxide anion production (RMSAP), and mRNA expression of NAD(P)H oxidase and superoxide dismutase were also assessed. In SHM (n=11) and AD (n=15) groups of S-I, LNaMAP-pdMAP was 10.5±2.1 vs 23±2.1 mmHg (P<0.001), and the salt-sensitivity index (SSi; HNaMAP−LNaMAP) was 6.0±1.9 vs 12.7±1.9 mmHg (P=0.03), respectively. In the SHM group, all rats were normotensive, and 36% were salt sensitive (SSi≥10 mmHg), whereas in the AD group ∼50% showed cSSHT. A 45% reduction in pNOB (P≤0.004) was observed in both groups in dietary transit. RMSAP increased in the AD group on both diets but more so on the HNa diet (S-II, P<0.03) than on the LNa diet (S-III, P<0.04). MAP modeling in rats without a renal hypertensive genotype indicated that the AD*HNa diet interaction (P=0.008) increases the likelihood of developing cSSHT. Translationally, these findings help to explain why subjects with clinical salt-sensitive normotension may transition to cSSHT.

Population dynamics of iron-oxidizing communities in pilot plants for the treatment of acid mine waters.

Science.gov (United States)

Heinzel, Elke; Janneck, Eberhard; Glombitza, Franz; Schlömann, Michael; Seifert, Jana

2009-08-15

The iron-oxidizing microbial community in two pilot plants for the treatment of acid mine water was monitored to investigate the influence of different process parameters such as pH, iron concentration, and retention time on the stability of the system to evaluate the applicability of this treatment technology on an industrial scale. The dynamics of the microbial populations were followed using T-RFLP (terminal restriction fragment length polymorphism) over a period of several months. For a more precise quantification, two TaqMan assays specific for the two prominent groups were developed and the relative abundance of these taxa in the iron-oxidizing community was verified by real-time PCR. The investigations revealed that the iron-oxidizing community was clearly dominated by two groups of Betaproteobacteria affiliated with the poorly known and not yet recognized species "Ferrovum myxofaciens" and with strains related to Gallionella ferruginea, respectively. These taxa dominated the microbial community during the whole investigation period and accelerated the oxidation of ferrous iron despite the changing characteristics of mine waters flowing into the plants. Thus, it is assumed that the treatment technology can also be applied to other mine sites and that these organisms play a crucial role in such treatment systems.

EMC, RF, and Antenna Systems in Miniature Electronic Devices

DEFF Research Database (Denmark)

Ruaro, Andrea

Advanced techniques for the control of electromagnetic interference (EMI) and for the optimization of the electromagnetic compatibility (EMC) performance has been developed under the constraints typical of miniature electronic devices (MED). The electromagnetic coexistence of multiple systems....... The structure allows for effective suppression of radiation from the MED, while taking into consideration the integration and miniaturization aspects. To increase the sensitivity of the system, a compact LNA suitable for on-body applications has been developed. The LNA allows for an increase in the overall...

MicroRNA-146a Regulates Perfusion Recovery in Response to Arterial Occlusion via Arteriogenesis

Directory of Open Access Journals (Sweden)

Joshua L. Heuslein

2018-01-01

Full Text Available The growth of endogenous collateral arteries that bypass arterial occlusion(s, or arteriogenesis, is a fundamental shear stress-induced adaptation with implications for treating peripheral arterial disease. MicroRNAs (miRs are key regulators of gene expression in response to injury and have strong therapeutic potential. In a previous study, we identified miR-146a as a candidate regulator of vascular remodeling. Here, we tested whether miR-146a regulates in vitro angiogenic endothelial cell (EC behaviors, as well as perfusion recovery, arteriogenesis, and angiogenesis in response to femoral arterial ligation (FAL in vivo. We found miR-146a inhibition impaired EC tube formation and migration in vitro. Following FAL, Balb/c mice were treated with a single, intramuscular injection of anti-miR-146a or scramble locked nucleic acid (LNA oligonucleotides directly into the non-ischemic gracilis muscles. Serial laser Doppler imaging demonstrated that anti-miR-146a treated mice exhibited significantly greater perfusion recovery (a 16% increase compared mice treated with scramble LNA. Moreover, anti-miR-146a treated mice exhibited a 22% increase in collateral artery diameter compared to controls, while there was no significant effect on in vivo angiogenesis or muscle regeneration. Despite exerting no beneficial effects on angiogenesis, the inhibition of mechanosensitive miR-146a enhances perfusion recovery after FAL via enhanced arteriogenesis.

Perancangan Low Noise Amplifier dengan Teknik Non Simultaneous Conjugate Match untuk Aplikasi Radar S-Band

Directory of Open Access Journals (Sweden)

Yana Taryana

2016-06-01

Full Text Available Radar merupakan sistem pemancar dan penerima gelombang elektromagnetik untuk mendeteksi, mengukur jarak dan membuat peta benda benda seperti pesawat terbang, kapal laut, kendaran bermotor dan informasi cuaca. Salah satu kendala yang dihadapi pada sistem radar adalah sinyal pantulan yang memiliki daya yang rendah sehingga kualitas penerimaan menjadi kurang baik. Untuk mengatasi kendala tersebut dibutuhkan penguat daya pada sistem penerima yaitu Low Noise Amplifier (LNA. Oleh karena itu, tulisan ini memaparkan perancangan LNA dengan menggunakan teknik Non Simultaneous Conjugate Match (NSCM untuk aplikasi radar S-Band. Teknik ini memberikan kemudahan dalam menentukan nilai trade off (TO untuk nilai gain, noise figure (NF dan Voltage Standing Wave Ratio (VSWR yang diinginkan. Dalam proses perancangannya, perangkat lunak Agilent Design System (ADS 2011 digunakan untuk mendapatkan hubungan antara lingkaran gain, lingkaran NF, lingkaran VSWR, dan lingkaran mismatch factor (M. Dari hubungan tersebut diperoleh nilai impedansi masukan dan keluaran dari komponen aktif. Dalam tulisan ini, LNA dirancang dua tingkat untuk mendapatkan penguatan yang tinggi. Masing-masing tingkat menggunakan komponen aktif BJT BFP420 dengan penguatan dirancang sebesar 13,50 dB untuk tingkat pertama dan kedua, dan M sebesar 0,98. Sedangkan untuk saluran penyesuai impedansinya menggunakan substrat teflon fiberglass DiClad527. Hasil simulasi menunjukkan karakteristik LNA pada frekuensi 3 GHz yaitu gain sebesar 28,80 dB, NF sebesar 2,80 dB, VSWRin sebesar 1,05 dan VSWRout sebesar 1,1.

Design of low power common-gate low noise amplifier for 2.4 GHz wireless sensor network applications

International Nuclear Information System (INIS)

Zhang Meng; Li Zhiqun

2012-01-01

This paper presents a differential low power low noise amplifier designed for the wireless sensor network (WSN) in a TSMC 0.18 μm RF CMOS process. A two-stage cross-coupling cascaded common-gate (CG) topology has been designed as the amplifier. The first stage is a capacitive cross-coupling topology. It can reduce the power and noise simultaneously. The second stage is a positive feedback cross-coupling topology, used to set up a negative resistance to enhance the equivalent Q factor of the inductor at the load to improve the gain of the LNA. A differential inductor has been designed as the load to achieve reasonable gain. This inductor has been simulated by the means of momentum electromagnetic simulation in ADS. A 'π' circuit model has been built as the inductor model by iteration in ADS. The inductor has been fabricated separately to verify the model. The LNA has been fabricated and measured. The LNA works well centered at 2.44 GHz. The measured gain S 21 is variable with high gain at 16.8 dB and low gain at 1 dB. The NF (noise figure) at high gain mode is 3.6 dB, the input referenced 1 dB compression point (IP1dB) is about −8 dBm and the IIP3 is 2 dBm at low gain mode. The LNA consumes about 1.2 mA current from 1.8 V power supply.

Real-time PCR based on SYBR-Green I fluorescence: An alternative to the TaqMan assay for a relative quantification of gene rearrangements, gene amplifications and micro gene deletions

Directory of Open Access Journals (Sweden)

Puisieux Alain

2003-10-01

Full Text Available Abstract Background Real-time PCR is increasingly being adopted for RNA quantification and genetic analysis. At present the most popular real-time PCR assay is based on the hybridisation of a dual-labelled probe to the PCR product, and the development of a signal by loss of fluorescence quenching as PCR degrades the probe. Though this so-called 'TaqMan' approach has proved easy to optimise in practice, the dual-labelled probes are relatively expensive. Results We have designed a new assay based on SYBR-Green I binding that is quick, reliable, easily optimised and compares well with the published assay. Here we demonstrate its general applicability by measuring copy number in three different genetic contexts; the quantification of a gene rearrangement (T-cell receptor excision circles (TREC in peripheral blood mononuclear cells; the detection and quantification of GLI, MYC-C and MYC-N gene amplification in cell lines and cancer biopsies; and detection of deletions in the OPA1 gene in dominant optic atrophy. Conclusion Our assay has important clinical applications, providing accurate diagnostic results in less time, from less biopsy material and at less cost than assays currently employed such as FISH or Southern blotting.

Using MEMS Capacitive Switches in Tunable RF Amplifiers

OpenAIRE

Danson John; Plett Calvin; Tait Niall

2006-01-01

A MEMS capacitive switch suitable for use in tunable RF amplifiers is described. A MEMS switch is designed, fabricated, and characterized with physical and RF measurements for inclusion in simulations. Using the MEMS switch models, a dual-band low-noise amplifier (LNA) operating at GHz and GHz, and a tunable power amplifier (PA) at GHz are simulated in m CMOS. MEMS switches allow the LNA to operate with 11 dB of isolation between the two bands while maintaining dB of gain and sub- dB no...

First Application of Newly Developed FT-NIR Spectroscopic Methodology to Predict Authenticity of Extra Virgin Olive Oil Retail Products in the USA.

Science.gov (United States)

Mossoba, Magdi M; Azizian, Hormoz; Fardin-Kia, Ali Reza; Karunathilaka, Sanjeewa R; Kramer, John K G

2017-05-01

Economically motivated adulteration (EMA) of extra virgin olive oils (EVOO) has been a worldwide problem and a concern for government regulators for a long time. The US Food and Drug Administration (FDA) is mandated to protect the US public against intentional adulteration of foods and has jurisdiction over deceptive label declarations. To detect EMA of olive oil and address food safety vulnerabilities, we used a previously developed rapid screening methodology to authenticate EVOO. For the first time, a recently developed FT-NIR spectroscopic methodology in conjunction with partial least squares analysis was applied to commercial products labeled EVOO purchased in College Park, MD, USA to rapidly predict whether they are authentic, potentially mixed with refined olive oil (RO) or other vegetable oil(s), or are of lower quality. Of the 88 commercial products labeled EVOO that were assessed according to published specified ranges, 33 (37.5%) satisfied the three published FT-NIR requirements identified for authentic EVOO products which included the purity test. This test was based on limits established for the contents of three potential adulterants, oils high in linoleic acid (OH-LNA), oils high in oleic acid (OH-OLA), palm olein (PO), and/or RO. The remaining 55 samples (62.5%) did not meet one or more of the criteria established for authentic EVOO. The breakdown of the 55 products was EVOO potentially mixed with OH-LNA (25.5%), OH-OLA (10.9%), PO (5.4%), RO (25.5%), or a combination of any of these four (32.7%). If assessments had been based strictly on whether the fatty acid composition was within the established ranges set by the International Olive Council (IOC), less than 10% would have been identified as non-EVOO. These findings are significant not only because they were consistent with previously published data based on the results of two sensory panels that were accredited by IOC but more importantly each measurement/analysis was accomplished in less than 5

Multiplex Real-Time PCR Assay Using TaqMan Probes for the Identification of Trypanosoma cruzi DTUs in Biological and Clinical Samples

Science.gov (United States)

Cura, Carolina I.; Duffy, Tomas; Lucero, Raúl H.; Bisio, Margarita; Péneau, Julie; Jimenez-Coello, Matilde; Calabuig, Eva; Gimenez, María J.; Valencia Ayala, Edward; Kjos, Sonia A.; Santalla, José; Mahaney, Susan M.; Cayo, Nelly M.; Nagel, Claudia; Barcán, Laura; Málaga Machaca, Edith S.; Acosta Viana, Karla Y.; Brutus, Laurent; Ocampo, Susana B.; Aznar, Christine; Cuba Cuba, Cesar A.; Gürtler, Ricardo E.; Ramsey, Janine M.; Ribeiro, Isabela; VandeBerg, John L.; Yadon, Zaida E.; Osuna, Antonio; Schijman, Alejandro G.

2015-01-01

Background Trypanosoma cruzi has been classified into six Discrete Typing Units (DTUs), designated as TcI–TcVI. In order to effectively use this standardized nomenclature, a reproducible genotyping strategy is imperative. Several typing schemes have been developed with variable levels of complexity, selectivity and analytical sensitivity. Most of them can be only applied to cultured stocks. In this context, we aimed to develop a multiplex Real-Time PCR method to identify the six T. cruzi DTUs using TaqMan probes (MTq-PCR). Methods/Principal Findings The MTq-PCR has been evaluated in 39 cultured stocks and 307 biological samples from vectors, reservoirs and patients from different geographical regions and transmission cycles in comparison with a multi-locus conventional PCR algorithm. The MTq-PCR was inclusive for laboratory stocks and natural isolates and sensitive for direct typing of different biological samples from vectors, reservoirs and patients with acute, congenital infection or Chagas reactivation. The first round SL-IR MTq-PCR detected 1 fg DNA/reaction tube of TcI, TcII and TcIII and 1 pg DNA/reaction tube of TcIV, TcV and TcVI reference strains. The MTq-PCR was able to characterize DTUs in 83% of triatomine and 96% of reservoir samples that had been typed by conventional PCR methods. Regarding clinical samples, 100% of those derived from acute infected patients, 62.5% from congenitally infected children and 50% from patients with clinical reactivation could be genotyped. Sensitivity for direct typing of blood samples from chronic Chagas disease patients (32.8% from asymptomatic and 22.2% from symptomatic patients) and mixed infections was lower than that of the conventional PCR algorithm. Conclusions/Significance Typing is resolved after a single or a second round of Real-Time PCR, depending on the DTU. This format reduces carryover contamination and is amenable to quantification, automation and kit production. PMID:25993316

Anti-parallel triplexes

DEFF Research Database (Denmark)

Kosbar, Tamer R.; Sofan, Mamdouh A.; Waly, Mohamed A.

2015-01-01

about 6.1 °C when the TFO strand was modified with Z and the Watson-Crick strand with adenine-LNA (AL). The molecular modeling results showed that, in case of nucleobases Y and Z a hydrogen bond (1.69 and 1.72 Å, respectively) was formed between the protonated 3-aminopropyn-1-yl chain and one...... of the phosphate groups in Watson-Crick strand. Also, it was shown that the nucleobase Y made a good stacking and binding with the other nucleobases in the TFO and Watson-Crick duplex, respectively. In contrast, the nucleobase Z with LNA moiety was forced to twist out of plane of Watson-Crick base pair which......The phosphoramidites of DNA monomers of 7-(3-aminopropyn-1-yl)-8-aza-7-deazaadenine (Y) and 7-(3-aminopropyn-1-yl)-8-aza-7-deazaadenine LNA (Z) are synthesized, and the thermal stability at pH 7.2 and 8.2 of anti-parallel triplexes modified with these two monomers is determined. When, the anti...

Reduced linear noise approximation for biochemical reaction networks with time-scale separation: The stochastic tQSSA+

Science.gov (United States)

Herath, Narmada; Del Vecchio, Domitilla

2018-03-01

Biochemical reaction networks often involve reactions that take place on different time scales, giving rise to "slow" and "fast" system variables. This property is widely used in the analysis of systems to obtain dynamical models with reduced dimensions. In this paper, we consider stochastic dynamics of biochemical reaction networks modeled using the Linear Noise Approximation (LNA). Under time-scale separation conditions, we obtain a reduced-order LNA that approximates both the slow and fast variables in the system. We mathematically prove that the first and second moments of this reduced-order model converge to those of the full system as the time-scale separation becomes large. These mathematical results, in particular, provide a rigorous justification to the accuracy of LNA models derived using the stochastic total quasi-steady state approximation (tQSSA). Since, in contrast to the stochastic tQSSA, our reduced-order model also provides approximations for the fast variable stochastic properties, we term our method the "stochastic tQSSA+". Finally, we demonstrate the application of our approach on two biochemical network motifs found in gene-regulatory and signal transduction networks.

Tunable Balun Low-Noise Amplifier in 65nm CMOS Technology

Directory of Open Access Journals (Sweden)

J. Sturm

2014-04-01

Full Text Available The presented paper includes the design and implementation of a 65 nm CMOS low-noise amplifier (LNA based on inductive source degeneration. The amplifier is realized with an active balun enabling a single-ended input which is an important requirement for low-cost system on chip implementations. The LNA has a tunable bandpass characteristics from 4.7 GHz up to 5.6 GHz and a continuously tunable gain from 22 dB down to 0 dB, which enables the required flexibility for multi-standard, multi-band receiver architectures. The gain and band tuning is realized with an optimized tunable active resistor in parallel to a tunable L-C tank amplifier load. The amplifier achieves an IIP3 linearity of -8dBm and a noise figure of 2.7 dB at the highest gain and frequency setting with a low power consumption of 10 mW. The high flexibility of the proposed LNA structure together with the overall good performance makes it well suited for future multi-standard low-cost receiver front-ends.

Effects of 6 weeks oral administration of Phyllanthus acidus leaf water extract on the vascular functions of middle-aged male rats.

Science.gov (United States)

Chongsa, Watchara; Kanokwiroon, Kanyanatt; Jansakul, Chaweewan

2015-12-24

Leaves of Phyllanthus acidus (PA) have been used in Thai traditional medicine for the treatment of hypertension. We have previously shown that chronic treatment of a PA water extract to middle-aged male rats caused a lowering of the body and serum lipids, two of the parameters that are implicated in cardiovascular disease. To investigate if chronic treatment of middle-aged male rats with a PA water extract affected the perivascular (aortic) adipose tissue (PVAT) and/or their vascular functions Fresh leaves of PA were extracted with water and orally gavaged to the middle-aged male rats for 6 weeks. Vascular functions were studied in vitro using isolated thoracic aorta with and without PVAT, and mesenteric rings in Krebs Heinseleit solution with results recorded with a Polygraph or a Myograph system. The amount of blood vessel eNOS and CSE (cystathionine-γ-lyase) expression was measured by Western blotting. PA treatment caused a lower maximal contractile response to phenylephrine (Phe) of the endothelium-intact aortic ring than that of the control group. This effect was abolished by N(G)-nitro-l-arginine (l-NA) or by denudation of the endothelium. dl-propargylglycine (PAG, H2S inhibitor) and TEA (Ca(2+)-activated K(+) channel blocker), but not glybenclamide (ATP-activated K(+) channel blocker), caused a similar increase in the baseline of the endothelium-intact aortic ring in the presence of l-NA in both the PA-treated and control aortic rings. This effect sequentially resulted in a greater contractile response of the aortic rings of both groups to Phe. Glybenclamide also caused a similar increase in the maximal contraction of the endothelium-intact blood vessels with l-NA to both groups. PAG, TEA or glybenclamide did not modify the phenylephrine C-R curves for either group of the PVAT-endothelium-intact aortic rings preincubated with l-NA. The CSE levels of the thoracic aorta and at the PVAT were not different between the PA-treated and the control group

MicroRNA expression in lung tissue and blood isolated from pigs suffering from bacterial pneumonia

DEFF Research Database (Denmark)

Skovgaard, Kerstin; Wendt, Karin Tarp; Heegaard, Peter M. H.

. No pathological changes were seen in lungs from control animals. All AP infected animals had a significantly higher level of mRNA coding for the acute-phase protein SAA-2 in the liver compared to the control group. Whole Blood samples were collected in PAXgene Blood RNA Tubes (PrenalytiX) before (control...... samples before and after infection were labelled with Hy5™ and Hy3™ fluorescent label, respectively, using the miRCURY™ LNA Array power labelling kit (Exiqon, Denmark). Sample were mixed pair-wise and hybridized to miRCURY™ LNA array version 11.0 (Exiqon, Denmark), which contains capture probes targeting...

New approaches for the standardization and validation of a real-time qPCR assay using TaqMan probes for quantification of yellow fever virus on clinical samples with high quality parameters.

Science.gov (United States)

Fernandes-Monteiro, Alice G; Trindade, Gisela F; Yamamura, Anna M Y; Moreira, Otacilio C; de Paula, Vanessa S; Duarte, Ana Cláudia M; Britto, Constança; Lima, Sheila Maria B

2015-01-01

The development and production of viral vaccines, in general, involve several steps that need the monitoring of viral load throughout the entire process. Applying a 2-step quantitative reverse transcription real time PCR assay (RT-qPCR), viral load can be measured and monitored in a few hours. In this context, the development, standardization and validation of a RT-qPCR test to quickly and efficiently quantify yellow fever virus (YFV) in all stages of vaccine production are extremely important. To serve this purpose we used a plasmid construction containing the NS5 region from 17DD YFV to generate the standard curve and to evaluate parameters such as linearity, precision and specificity against other flavivirus. Furthermore, we defined the limits of detection as 25 copies/reaction, and quantification as 100 copies/reaction for the test. To ensure the quality of the method, reference controls were established in order to avoid false negative results. The qRT-PCR technique based on the use of TaqMan probes herein standardized proved to be effective for determining yellow fever viral load both in vivo and in vitro, thus becoming a very important tool to assure the quality control for vaccine production and evaluation of viremia after vaccination or YF disease.

Understanding the link between meteorology and speciated abundance of bioaerosols in an urban environment using colocated flow cytometry and real-time autofluorescence measurements

Science.gov (United States)

Negron Marty, Arnaldo; DeLeon-Rodriguez, Natasha; Waters, Samantha; Ziemba, Luke; Anderson, Bruce; Bergin, Michael; Konstantinidis, Kostas; Nenes, Athanasios

2017-04-01

The abundance and speciation of primary biological atmospheric particles (PBAP) has been of great interest due to their potential impact on human health, cloud formation and contribution to atmospheric nutrient deposition [1, 2]. During this study state-of-the-art sampling techniques and protocols have been developed and combined with the speciation of PBAP by flow cytometry (FCM). An effective FCM protocol has been developed to identify and quantify speciated bioaerosols populations. In addition, a Wideband Integrated Bioaerosol Sensor (WIBS) has been used to understand the temporal variability of the PBAP, by measuring the autofluorescence of the atmospheric particles [3]. The techniques developed here have been applied to understand the PBAP variability and abundance in downtown Atlanta under different meteorological conditions. FCM results show the presence of a low nucleic acid (LNA) and a high nucleic acid (HNA) content subpopulation. The contribution of each subpopulation to the total biological atmospheric particles (TBAP) varies depending on the predominant meteorological conditions. Results suggest the HNA subpopulation, named fungal spores, dominates the composition of the TBAP during humid and warm days after rain events. However, during dry episodes the HNA subpopulation is diminished and the LNA subpopulation dominates the composition of the TBAP in downtown Atlanta. WIBS size distribution shifts between dry periods and humid and warm periods agreed well with the LNA and HNA subpopulations behavior. Our finding suggests Atlanta average PBAP concentration is around 1-8 x 104 part. /m3during Spring, where WIBS represents the lower bound and FCM the upper bound of the quantification. Additional experiments performed with different types of pollen, fungi and bacteria were used to better understand the scattering and fluorescence properties of them under different growing phases. References: [1] Morris, C. E., F. Conen, J. Alex Huffman, V. Phillips, U

Multiplex real-time PCR (TaqMan) assay for the simultaneous detection and discrimination of potato powdery and common scab diseases and pathogens.

Science.gov (United States)

Qu, X S; Wanner, L A; Christ, B J

2011-03-01

To develop a multiplex real-time PCR assay using TaqMan probes for the simultaneous detection and discrimination of potato powdery scab and common scab, two potato tuber diseases with similar symptoms, and the causal pathogens Spongospora subterranea and plant pathogenic Streptomyces spp. Real-time PCR primers and a probe for S. subterranea were designed based on the DNA sequence of the ribosomal RNA ITS2 region. Primers and a probe for pathogenic Streptomyces were designed based on the DNA sequence of the txtAB genes. The two sets of primer pairs and probes were used in a single real-time PCR assay. The multiplex real-time PCR assay was confirmed to be specific for S. subterranea and pathogenic Streptomyces. The assay detected DNA quantities of 100 fg for each of the two pathogens and linear responses and high correlation coefficients between the amount of DNA and C(t) values for each pathogen were achieved. The presence of two sets of primer pairs and probes and of plant extracts did not alter the sensitivity and efficiency of multiplex PCR amplification. Using the PCR assay, we could discriminate between powdery scab and common scab tubers with similar symptoms. Common scab and powdery scab were detected in some tubers with no visible symptoms. Mixed infections of common scab and powdery scab on single tubers were also revealed. This multiplex real-time PCR assay is a rapid, cost efficient, specific and sensitive tool for the simultaneous detection and discrimination of the two pathogens on infected potato tubers when visual symptoms are inconclusive or not present. Accurate and quick identification and discrimination of the cause of scab diseases on potatoes will provide critical information to potato growers and researchers for disease management. This is important because management strategies for common and powdery scab diseases are very different. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Detection and differentiation of Cryptosporidium by real-time polymerase chain reaction in stool samples from patients in Rio de Janeiro, Brazil

Directory of Open Access Journals (Sweden)

Roberta Flávia Ribeiro Rolando

2012-06-01

Full Text Available This study reports the first genetic characterisation of Cryptosporidium isolates in Brazil using real-time polymerase chain reaction (RT-PCR. A total of 1,197 faecal specimens from children and 10 specimens from human immunodeficiency virus-infected patients were collected between 1999-2010 and screened using microscopy. Forty-eight Cryptosporidium oocyst-positive isolates were identified and analysed using a generic TaqMan assay targeting the 18S rRNA to detect Cryptosporidium species and two other TaqMan assays to identify Cryptosporidium hominis and Cryptosporidium parvum. The 18S rRNA assay detected Cryptosporidium species in all 48 of the stool specimens. The C. parvum TaqMan assay correctly identified five/48 stool samples, while 37/48 stool specimens were correctly amplified in the C. hominis TaqMan assay. The results obtained in this study support previous findings showing that C. hominis infections are more prevalent than C. parvum infections in Brazil and they demonstrate that the TaqMan RT-PCR procedure is a simple, fast and valuable tool for the detection and differentiation of Cryptosporidium species.

A ratiometric electrochemical biosensor for the exosomal microRNAs detection based on bipedal DNA walkers propelled by locked nucleic acid modified toehold mediate strand displacement reaction.

Science.gov (United States)

Zhang, Jing; Wang, Liang-Liang; Hou, Mei-Feng; Xia, Yao-Kun; He, Wen-Hui; Yan, An; Weng, Yun-Ping; Zeng, Lu-Peng; Chen, Jing-Hua

2018-04-15

Sensitive and selective detection of microRNAs (miRNAs) in cancer cells derived exosomes have attracted rapidly growing interest owing to their potential in diagnostic and prognostic applications. Here, we design a ratiometric electrochemical biosensor based on bipedal DNA walkers for the attomolar detection of exosomal miR-21. In the presence of miR-21, DNA walkers are activated to walk continuously along DNA tracks, resulting in conformational changes as well as considerable increases of the signal ratio produced by target-respond and target-independent reporters. With the signal cascade amplification of DNA walkers, the biosensor exhibits ultrahigh sensitivity with the limit of detection (LOD) down to 67 aM. Furthermore, owing to the background-correcting function of target-independent reporters termed as reference reporters, the biosensor is robust and stable enough to be applied in the detection of exosomal miR-21 extracted from breast cancer cell lines and serums. In addition, because locked nucleic acid (LNA) modified toehold mediate strand displacement reaction (TMSDR) has extraordinary discriminative ability, the biosensor displays excellent selectivity even against the single-base-mismatched target. It is worth mentioning that our sensor is regenerative and stable for at least 5 cycles without diminution in sensitivity. In brief, the high sensitivity, selectivity and reproducibility, together with cheap, make the proposed biosensor a promising approach for exosomal miRNAs detection, in conjunction with early point-of-care testing (POCT) of cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of a Multiplex Real-Time Reverse Transcriptase PCR Assay for Detection and Differentiation of Influenza Viruses A and B during the 2001-2002 Influenza Season in Israel

Science.gov (United States)

Hindiyeh, Musa; Levy, Virginia; Azar, Roberto; Varsano, Noemi; Regev, Liora; Shalev, Yael; Grossman, Zehava; Mendelson, Ella

2005-01-01

The ability to rapidly diagnose influenza virus infections is of the utmost importance in the evaluation of patients with upper respiratory tract infections. It is also important for the influenza surveillance activities performed by national influenza centers. In the present study we modified a multiplex real-time reverse transcriptase PCR (RT-PCR) assay (which uses TaqMan chemistry) and evaluated it for its ability to detect and concomitantly differentiate influenza viruses A and B in 370 patient samples collected during the 2001-2002 influenza season in Israel. The performance of the TaqMan assay was compared to those of a multiplex one-step RT-PCR with gel detection, a shell vial immunofluorescence assay, and virus isolation in tissue culture. The TaqMan assay had an excellent sensitivity for the detection of influenza viruses compared to that of tissue culture. The overall sensitivity and specificity of the TaqMan assay compared to the results of culture were 98.4 and 85.5%, respectively. The sensitivity and specificity of the TaqMan assay for the detection of influenza virus A alone were 100 and 91.1%, respectively. On the other hand, the sensitivity and specificity for the detection of influenza virus B alone were 95.7 and 98.7%, respectively. The rapid turnaround time for the performance of the TaqMan assay (4.5 h) and the relatively low direct cost encourage the routine use of this assay in place of tissue culture. We conclude that the multiplex TaqMan assay is highly suitable for the rapid diagnosis of influenza virus infections both in well-established molecular biology laboratories and in reference clinical laboratories. PMID:15695650

Composicao quimica, perfil de acidos graxos e quantificacao dos acidos ƒ¿-linolenico, eicosapentaenoico e docosahexaenoico em visceras de tilapias (Oreochromis niloticus = Percentual composition, fatty acids and quantification of the LNA (Alfa-Linolenic, EPA (Eicosapentaenoic and DHA (Docosahexaenoic acids in visceras of Nile Tilapia (Oreochromis niloticus

Directory of Open Access Journals (Sweden)

Nilson Evelázio de Souza

2005-01-01

Full Text Available Foi avaliada a composição química de vísceras de tilápias (Oreochromis niloticus criadas em cativeiro Os teores de umidade, cinza, proteína bruta e lipídios totais foram de 64,4%; 1,3%; 6,3% e 18,0%, respectivamente, caracterizando alta concentração de lipídiostotais em relação a outros resíduos de peixes. Foram identificados 49 ácidos graxos, sendo majoritários os ácidos: oléico, (32,8%, seguido do palmítico, (19,9% e linoléico, (18,2%. As razões entre n-6/n-3 e ácidos poliinsaturados/saturados foram de 5,5 e 0,9, respectivamente. As quantificações dos ácidos graxos alfa-linolênico, eicosapentaenóico e docosahexaenóico, em mg/g de lipídios totais, foram de 10,4, 1,4 e 9,3, respectivamente. O elevado teor de lipídios totais das vísceras contribuiu significativamente para as quantidadesde ácidos graxos n-3. Todos os parâmetros analisados foram satisfatórios sob o ponto de vista nutricional e neste sentido as vísceras de tilápias poderão ser utilizadaa para alimentar peixes ou outros animais.The chemical composition was evaluated in visceras of tilapias raised in captivity. The moisture, ash, crude protein and total lipids contents were 64.4%; 1.3%; 6.3% and 18.0%, respectively, characterizing high total lipids concentration in relation other residues of fish. Forty nine fatty acids were detected, the major fatty acids were oleic (32.8%, palmitic (19.9% and linoleic-1 (18.2% and oleic (9.4%. The ratio n-6/n-3 and polyunsaturated/saturated fatty acids, showed the values 5.5 and 0.9, respectively. The quantifications of alfa-linolenic, eicosapentaenoic and docosahexaenoic acids (in mg/g of total lipids, were 10.4, 1.4 and 0.3, respectively. The higher contents of total lipids in visceras contributed significantly for amounts of n-3 fatty acids. All the parameters analyzed were shown nutritional value satisfactory in this sense visceras of tilapias can be used in the feed of fish and other animal.

Comparing Metabolic Functionalities, Community Structures, and Dynamics of Herbicide-Degrading Communities Cultivated with Different Substrate Concentrations

DEFF Research Database (Denmark)

Gözdereliler, Erkin; Boon, Nico; Aamand, Jens

2013-01-01

Two 4-chloro-2-methylphenoxyacetic acid (MCPA)-degrading enrichment cultures selected from an aquifer on low (0.1 mg liter−1) or high (25 mg liter−1) MCPA concentrations were compared in terms of metabolic activity, community composition, population growth, and single cell physiology. Different...... community compositions and major shifts in community structure following exposure to different MCPA concentrations were observed using both 16S rRNA gene denaturing gradient gel electrophoresis fingerprinting and pyrosequencing. The communities also differed in their MCPA-mineralizing activities...... activity in cultures selected on low herbicide concentrations. This suggests that LNA bacteria may play a role in degradation of low herbicide concentrations in aquifers impacted by agriculture. This study shows that subpopulations of herbicide-degrading bacteria that are adapted to different pesticide...

Hybridization-Based Detection of Helicobacter pylori at Human Body Temperature Using Advanced Locked Nucleic Acid (LNA) Probes

DEFF Research Database (Denmark)

Fontenete, Sílvia; Guimarães, Nuno; Leite, Marina

2013-01-01

The understanding of the human microbiome and its influence upon human life has long been a subject of study. Hence, methods that allow the direct detection and visualization of microorganisms and microbial consortia (e.g. biofilms) within the human body would be invaluable. In here, we assessed...

Chronic high-sodium diet increases aortic wall endothelin-1 expression in a blood pressure-independent fashion in rats.

Science.gov (United States)

Tsai, Yu-Hwai; Ohkita, Mamoru; Gariepy, Cheryl E

2006-06-01

Vascular endothelin (ET)-1 is upregulated in several forms of salt-induced hypertension. It is unclear to what extent these effects are primary or secondary to endothelial damage. We hypothesized that a high-sodium diet (HNa) increases vascular ET-1 production independent of arterial blood pressure changes. We investigated the effect of chronic HNa with and without ET(A) blockade on circulating and aortic ET-1 protein levels as well as aortic expression of ET-1 and ET(A) messenger RNA (mRNA) in inbred Wistar-Kyoto (WKY) and congenic ET(B)-deficient rats. Comparing WKY rats fed a low-sodium diet (LNa) with those fed HNa for 3 weeks, aortic wall ET-1 protein is significantly increased in response to HNa (331 +/- 43 pg/g tissue for LNa vs. 557 +/- 34 pg/gm tissue for HNa). HNa also increased aortic wall ET-1 mRNA levels by 40%, as determined by quantitative reverse transcriptase polymerase chain reaction. We then compared rats chronically treated with the ET(A)-selective antagonist, ABT-627, while receiving either LNa or HNa. There were no differences in arterial blood pressure (mean arterial pressure 89 +/- 1 mm Hg for WKY on LNa; 90 +/- 3 for WKY on HNa; 91 +/- 2 for ET(B)-deficient/ABT-627-treated on HNa) or heart rate. However, aortic wall ET-1 protein levels were 4-fold higher in the HNa group. Further, HNa increased aortic wall ET-1 mRNA (approximately 1.5- to 3-fold) and ET(A) mRNA (approximately 2- to 7-fold), independent of activation of ET(B). Therefore, the expression of ET-1 mRNA by the aortic wall is increased in response to chronic high dietary sodium in WKY rats in the absence of changes in arterial blood pressure.

Using MEMS Capacitive Switches in Tunable RF Amplifiers

Directory of Open Access Journals (Sweden)

Danson John

2006-01-01

Full Text Available A MEMS capacitive switch suitable for use in tunable RF amplifiers is described. A MEMS switch is designed, fabricated, and characterized with physical and RF measurements for inclusion in simulations. Using the MEMS switch models, a dual-band low-noise amplifier (LNA operating at GHz and GHz, and a tunable power amplifier (PA at GHz are simulated in m CMOS. MEMS switches allow the LNA to operate with 11 dB of isolation between the two bands while maintaining dB of gain and sub- dB noise figure. MEMS switches are used to implement a variable matching network that allows the PA to realize up to 37% PAE improvement at low input powers.

Analysis of Human TAAR8 and Murine Taar8b Mediated Signaling Pathways and Expression Profile

Directory of Open Access Journals (Sweden)

Jessica Mühlhaus

2014-11-01

Full Text Available The thyroid hormone derivative 3-iodothyronamine (3-T1AM exerts metabolic effects in vivo that contradict known effects of thyroid hormones. 3-T1AM acts as a trace amine-associated receptor 1 (TAAR1 agonist and activates Gs signaling in vitro. Interestingly, 3-T1AM-meditated in vivo effects persist in Taar1 knockout-mice indicating that further targets of 3-T1AM might exist. Here, we investigated another member of the TAAR family, the only scarcely studied mouse and human trace-amine-associated receptor 8 (Taar8b, TAAR8. By RT-qPCR and locked-nucleic-acid (LNA in situ hybridization, Taar8b expression in different mouse tissues was analyzed. Functionally, we characterized TAAR8 and Taar8b with regard to cell surface expression and signaling via different G-protein-mediated pathways. Cell surface expression was verified by ELISA, and cAMP accumulation was quantified by AlphaScreen for detection of Gs and/or Gi/o signaling. Activation of G-proteins Gq/11 and G12/13 was analyzed by reporter gene assays. Expression analyses revealed at most marginal Taar8b expression and no gender differences for almost all analyzed tissues. In heart, LNA-in situ hybridization demonstrated the absence of Taar8b expression. We could not identify 3-T1AM as a ligand for TAAR8 and Taar8b, but both receptors were characterized by a basal Gi/o signaling activity, a so far unknown signaling pathway for TAARs.

Understanding the effect of locked nucleic acid and 2'-O-methyl modification on the hybridization thermodynamics of a miRNA-mRNA pair in the presence and absence of AfPiwi protein.

Science.gov (United States)

Kumar, Santosh; Mapa, Koyeli; Maiti, Souvik

2014-03-18

miRNAs are some of the key epigenetic regulators of gene expression. They act through hybridization with their target mRNA and modulate the level of respective proteins via different mechanisms. Various cancer conditions are known to be associated with up- and downregulation of the oncogenic and tumor suppressor miRNAs, respectively. The levels of aberrantly expressed oncogenic miRNAs can be downregulated in different ways. Similarly, restoration of tumor suppressor miRNAs to their normal levels can be achieved using miRNA mimics. However, the use of miRNA mimics is limited by their reduced biostability and function. We have studied the hybridization thermodynamics of the miRNA 26a (11-mer, including the seed sequence) guide strand with the mRNA (11-mer) target strand in the absence and presence of AfPiwi protein. We have also inserted locked nucleic acids (LNAs) and 2'-O-methyl-modified nucleotides into the guide strand, in a walk-through manner, to assess their effect on the binding efficiency between guide and target RNA. Insertion of LNA and 2'-O-methyl-modified nucleotides into the guide strand helped to strengthen the binding affinity irrespective of the position of insertion. However, in the presence of AfPiwi protein, these modifications reduced the binding affinity to different extents depending on the position of insertion. Insertion of a modification leads to an increase in the enthalpic contribution with an increased unfavorable entropic contribution, which negatively compensates for the higher favorable enthalpy.

Maintaining K+ balance on the low-Na+, high-K+ diet

Science.gov (United States)

Cornelius, Ryan J.; Wang, Bangchen; Wang-France, Jun

2016-01-01

A low-Na+, high-K+ diet (LNaHK) is considered a healthier alternative to the “Western” high-Na+ diet. Because the mechanism for K+ secretion involves Na+ reabsorptive exchange for secreted K+ in the distal nephron, it is not understood how K+ is eliminated with such low Na+ intake. Animals on a LNaHK diet produce an alkaline load, high urinary flows, and markedly elevated plasma ANG II and aldosterone levels to maintain their K+ balance. Recent studies have revealed a potential mechanism involving the actions of alkalosis, urinary flow, elevated ANG II, and aldosterone on two types of K+ channels, renal outer medullary K+ and large-conductance K+ channels, located in principal and intercalated cells. Here, we review these recent advances. PMID:26739887

A pilot evaluation of whole blood finger-prick sampling for point-of-care HIV viral load measurement: the UNICORN study.

Science.gov (United States)

Fidler, Sarah; Lewis, Heather; Meyerowitz, Jodi; Kuldanek, Kristin; Thornhill, John; Muir, David; Bonnissent, Alice; Timson, Georgina; Frater, John

2017-10-20

There is a global need for HIV viral load point-of-care (PoC) assays to monitor patients receiving antiretroviral therapy. UNICORN was the first study of an off-label protocol using whole blood finger-prick samples tested with and without a simple three minute spin using a clinic-room microcentrifuge. Two PoC assays were evaluated in 40 HIV-positive participants, 20 with detectable and 20 with undetectable plasma viral load (pVL) (<20 copies/ml). Using 100 µl finger-prick blood samples, the Cepheid Xpert HIV-1 Viral Load and HIV-1 Qual cartridges were compared with laboratory pVL assessment (TaqMan, Roche). For participants with undetectable viraemia by TaqMan, there was poor concordance without centrifugation with the TaqMan platform with only 40% 'undetectable' using Xpert VL and 25% 'not detected' using the Qual assay. After a 3 minute spin, 100% of samples were undetectable using either assay, showing full concordance with the TaqMan assay. Defining a lower limit of detection of 1000 copies/ml when including a spin, there was 100% concordance with the TaqMan platform with strong correlation (rho 0.95 and 0.94; p < 0.0001 for both assays). When including a simple microcentrifugation step, finger-prick PoC testing was a quick and accurate approach for assessing HIV viraemia, with excellent concordance with validated laboratory approaches.

A real-time PCR assay for the relative quantification of the tetrahydrocannabinolic acid (THCA) synthase gene in herbal Cannabis samples.

Science.gov (United States)

Cascini, Fidelia; Passerotti, Stella; Martello, Simona

2012-04-10

In this study, we wanted to investigate whether or not the tetrahydrocannabinolic acid (THCA) synthase gene, which codes for the enzyme involved in the biosynthesis of THCA, influences the production and storage of tetrahydrocannabinol (THC) in a dose-dependent manner. THCA is actually decarboxylated to produce THC, the main psychoactive component in the Cannabis plant. Assuming as the research hypothesis a correlation between the gene copy number and the production of THC, gene quantification could be useful in forensics in order to complement or replace chemical analysis for the identification and classification of seized Cannabis samples, thus distinguishing the drug-type from the fibre-type varieties. A real-time PCR assay for the relative quantification of the THCA synthase gene was then validated on Cannabis samples; some were seized from the illegal drug market and others were derived from experimental cultivation. In order to determine the gene copy number to compare high vs. low potency plants, we chose the ΔΔCt method for TaqMan reactions. The assay enabled single plants with zero, one, and two copies of the gene to be distinguished. As a result of this first part of the research on the THCA synthase gene (the second part will cover a study of gene expression), we found no correlation between THCA synthase gene copy number and the content of THC in the herbal Cannabis samples tested. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Output-Conductance Transition-Free Method for Improving Radio-Frequency Linearity of SOI MOSFET Circuits

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A. Daghighi

2013-09-01

Full Text Available In this article, a novel concept is introduced to improve the radio frequency (RF linearity of partially-depleted (PD silicon-on-insulator (SOI MOSFET circuits. The transition due to the non-zero body resistance (RBody in output conductance of PD SOI devices leads to linearity degradation. A relation for RBody is defined to eliminate the transition and a method to obtain transition-free circuit is shown. 3-D Simulations of various body-contacted devices are carried out to extract the transition-free body resistances. To identify the output conductance transition-free concept and its application to RF circuits, a 2.4 GHz low noise amplifier (LNA is analyzed. Mixed mode device-circuit analysis is carried out to simultaneously solve device transport equations and circuit spice models. FFT calculations are performed on the output signal to compute harmonic distortion figures. Comparing the conventional body-contacted and transition-free SOI LNAs, third harmonic distortion (HD3 and total harmonic distortion (THD are improved by 16% and 24%, respectively. Two-tone test is used to analyze third order intermodulation distortions. OIP3 is improved in transition-free SOI LNA by 17% comparing with the conventional body-contacted SOI LNA. These results show the possibility of application of transition-free design concept to improve linearity of RF SOI MOSFET circuits.

Evaluation of perfluoroalkyl acid activity using primary mouse and human hepatocytes

International Nuclear Information System (INIS)

Rosen, Mitchell B.; Das, Kaberi P.; Wood, Carmen R.; Wolf, Cynthia J.; Abbott, Barbara D.; Lau, Christopher

2013-01-01

While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is known about the biological activity of other perfluoroalkyl acids (PFAAs) detected in the environment. Using a transient transfection assay developed in COS-1 cells, our group has previously evaluated a variety of PFAAs for activity associated with activation of peroxisome proliferator-activated receptor alpha (PPARα). Here we use primary heptatocytes to further assess the biological activity of a similar group of PFAAs using custom designed Taqman Low Density Arrays. Primary mouse and human hepatoyctes were cultured for 48 h in the presence of varying concentrations of 12 different PFAAs or Wy14,643, a known activator of PPARα. Total RNA was collected and the expression of 48 mouse or human genes evaluated. Gene selection was based on either in-house liver microarray data (mouse) or published data using primary hepatocytes (human). Gene expression in primary mouse hepatocytes was more restricted than expected. Genes typically regulated in whole tissue by PPARα agonists were not altered in mouse cells including Acox1, Me1, Acaa1a, Hmgcs1, and Slc27a1. Cyp2b10, a gene regulated by the constitutive androstane receptor and a transcript normally up-regulated by in vivo exposure to PFAAs, was also unchanged in cultured mouse hepatocytes. Cyp4a14, Ehhadh, Pdk4, Cpt1b, and Fabp1 were regulated as expected in mouse cells. A larger group of genes were differentially expressed in human primary hepatocytes, however, little consistency was observed across compounds with respect to which genes produced a significant dose response making the determination of relative biological activity difficult. This likely reflects weaker activation of PPARα in human versus rodent cells as well as variation among individual cell donors. Unlike mouse cells, CYP2B6 was up-regulated in human hepatocytes by a number of PFAAs as was PPARδ. Rankings were conducted on the limited

78 FR 20029 - Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance...

Science.gov (United States)

2013-04-03

..., Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance Exemption AGENCY... from the requirement of a tolerance for residues of castor oil, polymer with adipic acid, linoleic acid... pesticide formulation. Advance Polymer Technology submitted a petition to EPA under the Federal Food, Drug...

Micro-ribonucleic acid-binding site variants of type 2 diabetes candidate loci predispose to gestational diabetes mellitus in Chinese Han women.

Science.gov (United States)

Wang, Xiaojing; Li, Wei; Ma, Liangkun; Ping, Fan; Liu, Juntao; Wu, Xueyan; Mao, Jiangfeng; Wang, Xi; Nie, Min

2018-01-20

Emerging evidence has suggested that the genetic background of gestational diabetes mellitus (GDM) was analogous to type 2 diabetes mellitus. In contrast to type 2 diabetes mellitus, the genetic studies for GDM were limited. Accordingly, the aim of the present study was to extensively explore the influence of micro-ribonucleic acid-binding single-nucleotide polymorphisms (SNPs) in type 2 diabetes mellitus candidate loci on GDM susceptibility in Chinese. A total of 839 GDM patients and 900 controls were enrolled. Six micro-ribonucleic acid-binding SNPs were selected from 30 type 2 diabetes mellitus susceptibility loci and genotyped using TaqMan allelic discrimination assays. The minor allele of three SNPs, PAX4 rs712699 (OR 1.366, 95% confidence interval 1.021-1.828, P = 0.036), KCNB1 rs1051295 (OR 1.579, 95% confidence interval 1.172-2.128, P = 0.003) and MFN2 rs1042842 (OR 1.398, 95% confidence interval 1.050-1.862, P = 0.022) were identified to significantly confer higher a risk of GDM in the additive model. The association between rs1051295 and increased fasting plasma glucose (b = 0.006, P = 0.008), 3-h oral glucose tolerance test plasma glucose (b = 0.058, P = 0.025) and homeostatic model assessment of insulin resistance (b = 0.065, P = 0.017) was also shown. Rs1042842 was correlated with higher 3-h oral glucose tolerance test plasma glucose (b = 0.056, P = 0.028). However, no significant correlation between the other included SNPs (LPIN1 rs1050800, VPS26A rs1802295 and NLRP3 rs10802502) and GDM susceptibility were observed. The present findings showed that micro-ribonucleic acid-binding SNPs in type 2 diabetes mellitus candidate loci were also associated with GDM susceptibility, which further highlighted the similar genetic basis underlying GDM and type 2 diabetes mellitus. © 2018 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

[Studies on interaction of acid-treated nanotube titanic acid and amino acids].

Science.gov (United States)

Zhang, Huqin; Chen, Xuemei; Jin, Zhensheng; Liao, Guangxi; Wu, Xiaoming; Du, Jianqiang; Cao, Xiang

2010-06-01

Nanotube titanic acid (NTA) has distinct optical and electrical character, and has photocatalysis character. In accordance with these qualities, NTA was treated with acid so as to enhance its surface activity. Surface structures and surface groups of acid-treated NTA were characterized and analyzed by Transmission Electron Microscope (TEM) and Fourier Transform Infrared Spectrometry (FT-IR). The interaction between acid-treated NTA and amino acids was investigated. Analysis results showed that the lengths of acid-treated NTA became obviously shorter. The diameters of nanotube bundles did not change obviously with acid-treating. Meanwhile, the surface of acid-treated NTA was cross-linked with carboxyl or esterfunction. In addition, acid-treated NTA can catch amino acid residues easily, and then form close combination.

Geoarcheologický záznam středního a mladého paleolitu v jeskyni Kůlně, Moravský kras

Czech Academy of Sciences Publication Activity Database

Lisá, Lenka; Neruda, P.; Nerudová, Z.; Bajer, A.

2013-01-01

Roč. 98, č. 2 (2013), s. 197-214 ISSN 0323-0570 Institutional support: RVO:67985831 Keywords : Middle and Upper Palaeolithic * Kůlna cave * cave deposits * formation processes * micromorphology Subject RIV: AC - Archeology, Anthropology, Ethnology

Ibotenic acid and thioibotenic acid

DEFF Research Database (Denmark)

Hermit, Mette B; Greenwood, Jeremy R; Nielsen, Birgitte

2004-01-01

In this study, we have determined and compared the pharmacological profiles of ibotenic acid and its isothiazole analogue thioibotenic acid at native rat ionotropic glutamate (iGlu) receptors and at recombinant rat metabotropic glutamate (mGlu) receptors expressed in mammalian cell lines....... Thioibotenic acid has a distinct pharmacological profile at group III mGlu receptors compared with the closely structurally related ibotenic acid; the former is a potent (low microm) agonist, whereas the latter is inactive. By comparing the conformational energy profiles of ibotenic and thioibotenic acid...... with the conformations preferred by the ligands upon docking to mGlu1 and models of the other mGlu subtypes, we propose that unlike other subtypes, group III mGlu receptor binding sites require a ligand conformation at an energy level which is prohibitively expensive for ibotenic acid, but not for thioibotenic acid...

LNA effects on DNA binding and conformation

DEFF Research Database (Denmark)

Pabon-Martinez, Y Vladimir; Xu, You; Villa, Alessandra

2017-01-01

-substitution in the duplex pyrimidine strand alters the double helix structure, affecting x-displacement, slide and twist favoring triplex formation through enhanced TFO major groove accommodation. Collectively, these findings should facilitate the design of potent anti-gene ONs.......The anti-gene strategy is based on sequence-specific recognition of double-strand DNA by triplex forming (TFOs) or DNA strand invading oligonucleotides to modulate gene expression. To be efficient, the oligonucleotides (ONs) should target DNA selectively, with high affinity. Here we combined...... hybridization analysis and electrophoretic mobility shift assay with molecular dynamics (MD) simulations to better understand the underlying structural features of modified ONs in stabilizing duplex- and triplex structures. Particularly, we investigated the role played by the position and number of locked...

Short-term variability in bacterial abundance, cell properties, and incorporation of leucine and thymidine in subarctic sea ice

DEFF Research Database (Denmark)

Kaartokallio, H.; Sogaard, D. H.; Norman, L.

2013-01-01

Sea ice is a biome of immense size and provides a range of habitats for diverse microbial communities, many of which are adapted to living at low temperatures and high salinities in brines. We measured simultaneous incorporation of thymidine (TdR) and leucine (Leu), bacterial cell abundance...... and cell population properties (by flow cytometry) in subarctic sea ice in SW Greenland. Short-term temporal variability was moderate, and steep environmental gradients, typical for sea ice, were the main drivers of the variability in bacterial cell properties and activity. Low nucleic acid (LNA) bacteria...... and marine biofilm systems. Leu: TdR ratios were high (up to >300) in lowermost ice layers, and when compared to published respiration measurements, these results suggest non-specific Leu incorporation. There was evidence of polyhydroxyalkanoate (PHA)-containing bacteria in the sea ice, shown by brightly...

Enrichment of methylated molecules using enhanced-ice-co-amplification at lower denaturation temperature-PCR (E-ice-COLD-PCR) for the sensitive detection of disease-related hypermethylation.

Science.gov (United States)

Mauger, Florence; Kernaleguen, Magali; Lallemand, Céline; Kristensen, Vessela N; Deleuze, Jean-François; Tost, Jörg

2018-05-01

The detection of specific DNA methylation patterns bears great promise as biomarker for personalized management of cancer patients. Co-amplification at lower denaturation temperature-PCR (COLD-PCR) assays are sensitive methods, but have previously only been able to analyze loss of DNA methylation. Enhanced (E)-ice-COLD-PCR reactions starting from 2 ng of bisulfite-converted DNA were developed to analyze methylation patterns in two promoters with locked nucleic acid (LNA) probes blocking amplification of unmethylated CpGs. The enrichment of methylated molecules was compared to quantitative (q)PCR and quantified using serial dilutions. E-ice-COLD-PCR allowed the multiplexed enrichment and quantification of methylated DNA. Assays were validated in primary breast cancer specimens and circulating cell-free DNA from cancer patients. E-ice-COLD-PCR could prove a useful tool in the context of DNA methylation analysis for personalized medicine.

Chemometrics applied to the incorporation of omega-3 in tilapia fillet feed flaxseed flour

Directory of Open Access Journals (Sweden)

Márcia Fernandes Nishiyama

2014-09-01

Full Text Available This study evaluated the effect of adding flaxseed flour to the diet of Nile tilapia on the fatty acid composition of fillets using chemometrics. A traditional and an experimental diet containing flaxseed flour were used to feed the fish for 60 days. An increase of 18:3 n-3 and 22:6 n-3 and a decrease of 18:2 n-6 were observed in the tilapia fillets fed the experimental diet. There was a reduction in the n-6:n-3 ratio. A period of 45 days of incorporation caused a significant change in tilapia chemical composition. Principal Component Analysis showed that the time periods of 45 and 60 days positively contributed to the total content of n-3, LNA, and DHA, highlighting the effect of omega-3 incorporation in the treatment containing flaxseed flour.

The cobas p 630 instrument: a dedicated pre-analytic solution to optimize COBAS® AmpliPrep/COBAS® TaqMan® system workflow and turn-around-time.

Science.gov (United States)

Vallefuoco, L; Sorrentino, R; Spalletti Cernia, D; Colucci, G; Portella, G

2012-12-01

The cobas p 630, a fully automated pre-analytical instrument for primary tube handling recently introduced to complete the Cobas(®) TaqMan systems portfolio, was evaluated in conjunction with: the COBAS(®) AmpliPrep/COBAS(®) TaqMan HBV Test, v2.0, COBAS(®) AmpliPrep/COBAS(®) TaqMan HCV Test, v1.0 and COBAS(®) AmpliPrep/COBAS(®) TaqMan HIV Test, v2.0. The instrument performance in transferring samples from primary to secondary tubes, its impact in improving COBAS(®) AmpliPrep/COBAS(®) TaqMan workflow and hands-on reduction and the risk of possible cross-contamination were assessed. Samples from 42 HBsAg positive, 42 HCV and 42 HIV antibody (Ab) positive patients as well as 21 healthy blood donors were processed with or without automated primary tubes. HIV, HCV and HBsAg positive samples showed a correlation index of 0.999, 0.987 and of 0.994, respectively. To assess for cross-contamination, high titer HBV DNA positive samples, HCV RNA and HIV RNA positive samples were distributed in the cobas p 630 in alternate tube positions, adjacent to negative control samples within the same rack. None of the healthy donor samples showed any reactivity. Based on these results, the cobas p 630 can improve workflow and sample tracing in laboratories performing molecular tests, and reduce turnaround time, errors, and risks. Copyright © 2012 Elsevier B.V. All rights reserved.

Improving clinical laboratory efficiency: a time-motion evaluation of the Abbott m2000 RealTime and Roche COBAS AmpliPrep/COBAS TaqMan PCR systems for the simultaneous quantitation of HIV-1 RNA and HCV RNA.

Science.gov (United States)

Amendola, Alessandra; Coen, Sabrina; Belladonna, Stefano; Pulvirenti, F Renato; Clemens, John M; Capobianchi, M Rosaria

2011-08-01

Diagnostic laboratories need automation that facilitates efficient processing and workflow management to meet today's challenges for expanding services and reducing cost, yet maintaining the highest levels of quality. Processing efficiency of two commercially available automated systems for quantifying HIV-1 and HCV RNA, Abbott m2000 system and Roche COBAS Ampliprep/COBAS TaqMan 96 (docked) systems (CAP/CTM), was evaluated in a mid/high throughput workflow laboratory using a representative daily workload of 24 HCV and 72 HIV samples. Three test scenarios were evaluated: A) one run with four batches on the CAP/CTM system, B) two runs on the Abbott m2000 and C) one run using the Abbott m2000 maxCycle feature (maxCycle) for co-processing these assays. Cycle times for processing, throughput and hands-on time were evaluated. Overall processing cycle time was 10.3, 9.1 and 7.6 h for Scenarios A), B) and C), respectively. Total hands-on time for each scenario was, in order, 100.0 (A), 90.3 (B) and 61.4 min (C). The interface of an automated analyzer to the laboratory workflow, notably system set up for samples and reagents and clean up functions, are as important as the automation capability of the analyzer for the overall impact to processing efficiency and operator hands-on time.

[Acids in coffee. XI. The proportion of individual acids in the total titratable acid].

Science.gov (United States)

Engelhardt, U H; Maier, H G

1985-07-01

22 acids in ground roast coffees and instant coffees were determined by GLC of their silyl derivatives (after preseparation by gel electrophoresis) or isotachophoresis. The contribution to the total acidity (which was estimated by titration to pH 8 after cation exchange of the coffee solutions) was calculated for each individual acid. The mentioned acids contribute with 67% (roast coffee) and 72% (instant coffee) to the total acidity. In the first place citric acid (12.2% in roast coffee/10.7% in instant coffee), acetic acid (11.2%/8.8%) and the high molecular weight acids (8%/9%) contribute to the total acidity. Also to be mentioned are the shares of chlorogenic acids (9%/4.8%), formic acid (5.3%/4.6%), quinic acid (4.7%/5.9%), malic acid (3.9%/3%) and phosphoric acid (2.5%/5.2%). A notable difference in the contribution to total acidity between roast and instant coffee was found for phosphoric acid and pyrrolidonecarboxylic acid (0.7%/1.9%). It can be concluded that those two acids are formed or released from e.g. their esters in higher amounts than other acids during the production of instant coffee.

Emocionálna a sociálna inteligencia vo vzťahu k zvládaniu v ranej adolescencii

Czech Academy of Sciences Publication Activity Database

Baumgartner, František; Zacharová, Z.

2011-01-01

Roč. 5, č. 1 (2011), s. 1-15 ISSN 1802-8853 R&D Projects: GA ČR GA406/09/2096 Institutional research plan: CEZ:AV0Z70250504 Keywords : emotional intelligence * coping * early adolescence Subject RIV: AN - Psychology http://e-psycholog.eu/clanek/112

The acidic functional groups of humic acid

Energy Technology Data Exchange (ETDEWEB)

Shanxiang, Li; Shuhe, Sun; Zhai Zongxi, Wu Qihu

1983-09-01

The acidic functional groups content, pK value, DELTAH and DELTAS of humic acid (HA) and nitro-humic acid (NHA) were determined by potentiometry, conductometry and calorimetric titration. The thermodynamic parameters of carboxylic groups and phenolic hydroxyl groups of humic acid are similar to that of simple hydroxy-benzoic acid. The configuration sites of acidic functional groups in humic acid from different coals are different. The carbonyl groups on aromatic rings are probably ortho to phenolic -OH for HA and NHA extracted from Huangxian's brown coal and Japanese lignite, while those from Lingshi's weathered coal are not. The weak -COOH groups of the latter possess higher chemical activity. The -COOH content in HA increases, phenolic -OH group decreases and the chemical acidity of acidic functional groups increases when HA is oxidized by nitric acid. (14 refs.)

Radio Telescope Focal Container for the Russian VLBI Network of New Generation

Science.gov (United States)

Ipatov, Alexander; Mardyshkin, Vyacheslav; Cherepanov, Andrey; Chernov, Vitaly; Diky, Dmitry; Khvostov, Evgeny; Yevstigneyev, Alexander

2010-01-01

This article considers the development of the structure of receivers for Russian radio telescopes. The development of these radio telescopes is undertaken within the project for creating a Russian small-antenna-based radio interferometer of new generation. It is shown that for small antennas (10. 12 meter) the principal unit, which provides the best SNR, is the so-called focal container placed at primary focus. It includes the primary feed, HEMT LNA, and cryogenic cooling system down to 20. K. A new multi-band feed based on traveling wave resonators is used. It has small dimensions, low weight, and allows working with circular polarizations. Thus it can be placed into focal container and cooled with the LNA. A sketch of the focal container, with traveling-wave-resonator feed, and calculations of the expected parameters of the multi-band receiver are presented.

A single-to-differential low-noise amplifier with low differential output imbalance

International Nuclear Information System (INIS)

Duan Lian; Ma Chengyan; He Xiaofeng; Ye Tianchun; Huang Wei; Jin Yuhua

2012-01-01

This paper presents a single-ended input differential output low-noise amplifier intended for GPS applications. We propose a method to reduce the gain/amplitude and phase imbalance of a differential output exploiting the inductive coupling of a transformer or center-tapped differential inductor. A detailed analysis of the theory of imbalance reduction, as well as a discussion on the principle of choosing the dimensions of a transformer, are given. An LNA has been implemented using TSMC 0.18 μm technology with ESD-protected. Measurement on board shows a voltage gain of 24.6 dB at 1.575 GHz and a noise figure of 3.2 dB. The gain imbalance is below 0.2 dB and phase imbalance is less than 2 degrees. The LNA consumes 5.2 mA from a 1.8 V supply. (semiconductor integrated circuits)

A wideband CMOS inductorless low noise amplifier employing noise cancellation for digital TV tuner applications

International Nuclear Information System (INIS)

Zhang Jihong; Bai Xuefei; Huang Lu

2013-01-01

A wideband inductorless low noise amplifier for digital TV tuner applications is presented. The proposed LNA scheme uses a composite NMOS/PMOS cross-coupled transistor pair to provide partial cancellation of noise generated by the input transistors. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed LNA achieves 12.2–15.2 dB voltage gain from 300 to 900 MHz, the noise figure is below 3.1 dB and has a minimum value of 2.3 dB, and the best input-referred 1-dB compression point (IP1dB) is − 17 dBm at 900 MHz. The core consumes 7 mA current with a supply voltage of 1.8 V and occupies an area of 0.5 × 0.35 mm 2 . (semiconductor integrated circuits)

The Acid-Base Titration of a Very Weak Acid: Boric Acid

Science.gov (United States)

Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

2012-01-01

A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

Usnic acid controls the acidity tolerance of lichens

International Nuclear Information System (INIS)

Hauck, Markus; Juergens, Sascha-Rene

2008-01-01

The hypotheses were tested that, firstly, lichens producing the dibenzofuran usnic acid colonize substrates characterized by specific pH ranges, secondly, this preferred pH is in a range where soluble usnic acid and its corresponding anion occur in similar concentrations, and thirdly, usnic acid makes lichens vulnerable to acidity. Lichens with usnic acid prefer an ambient pH range between 3.5 and 5.5 with an optimum between 4.0 and 4.5. This optimum is close to the pK a1 value of usnic acid of 4.4. Below this optimum pH, dissolved SO 2 reduces the chlorophyll fluorescence yield more in lichens with than without their natural content of usnic acid. This suggests that usnic acid influences the acidity tolerance of lichens. The putative mechanism of the limited acidity tolerance of usnic acid-containing lichens is the acidification of the cytosol by molecules of protonated usnic acid shuttling protons through the plasma membrane at an apoplastic pH a1 . - Combined field and experimental data suggest that usnic acid makes lichens sensitive to acidity at pH <3.5

Heterotrophic bacterial responses to the winter–spring phytoplankton bloom in open waters of the NW Mediterranean

KAUST Repository

Gomes, Ana

2014-12-03

The response of planktonic heterotrophic prokaryotes to the NW Mediterranean winter–spring offshore phytoplankton bloom was assessed in 3 cruises conducted in March, April–May and September 2009. Bulk measurements of phytoplankton and bacterioplankton biomass and production were complemented with an insight into bacterial physiological structure by single-cell analysis of nucleic acid content [low (LNA) vs. high (HNA)] and membrane integrity (“Live” vs. “Dead” cells). Bacterial production empirical conversion factors (0.82±0.25 SE kg C mol leucine−1) were almost always well below the theoretical value. Major differences in most microbial variables were found among the 3 periods, which varied from extremely high phytoplankton biomass and production during the bloom in March (>1 g C m−2 d−1 primary production) to typically oligotrophic conditions during September stratification (<200 mg C m−2 d−1). In both these periods bacterial production was ~30 mg C m−2 d−1 while very large bacterial production (mean 228, with some stations exceeding 500 mg C m−2 d−1) but low biomass was observed during the April–May post-bloom phase. The contribution of HNA (30–67%) and “Live” cells (47–97%) were temporally opposite in the study periods, with maxima in March and September, respectively. Different relationships were found between physiological structure and bottom-up variables, with HNA bacteria apparently more responsive to phytoplankton only during the bloom, coinciding with larger average cell sizes of LNA bacteria. Moderate phytoplankton–bacterioplankton coupling of biomass and activity was only observed in the bloom and post-bloom phases, while relationships between both compartments were not significant under stratification. With all data pooled, bacteria were only weakly bottom-up controlled. Our analyses show that the biomass and production of planktonic algae and bacteria followed opposite paths in the transition from bloom to

[Teichoic acids from lactic acid bacteria].

Science.gov (United States)

Livins'ka, O P; Harmasheva, I L; Kovalenko, N K

2012-01-01

The current view of the structural diversity of teichoic acids and their involvement in the biological activity of lactobacilli has been reviewed. The mechanisms of effects of probiotic lactic acid bacteria, in particular adhesive and immunostimulating functions have been described. The prospects of the use of structure data of teichoic acid in the assessment of intraspecific diversity of lactic acid bacteria have been also reflected.

Preparation of fulvic acid and low-molecular organic acids by oxidation of weathered coal humic acid

Energy Technology Data Exchange (ETDEWEB)

Shinozuka, T.; Ito, A.; Sasaki, O.; Yazawa, Y.; Yamaguchi, T. [Chiba Institute of Technolgy, Chiba (Japan). Dept. of Industrial Chemistry

2002-07-01

Weathered coal contains much humic acid and a little fulvic acid. Therefore, the production of fulvic acid, the most valuable humic substance because of its water-solubility, was examined by ozone and hydrogen peroxide oxidation of humic acid extracted form Xinjiang (China) weathered coal. The resulting products of the oxidation were water soluble fulvic acid and organic acids, mainly formic acid and oxalic acid. The product yield of fulvic acid was 20 (C%) and that of organic acids were 39 (C%) for formic and acid 13 (C%) for oxalic acid. The formed fulvic acid showed a higher content of oxygen and carboxyl groups, than those of the extracted one from the original weathered coal.

Acid Rain

Science.gov (United States)

Bricker, Owen P.; Rice, Karen C.

1995-01-01

Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

Enzymatic formation of hexadecenoic acid from palmitic acid

International Nuclear Information System (INIS)

Nakano, Masao; Fujino, Yasuhiko

1975-01-01

Desaturation of palmitic acid was investigated in an enzyme system prepared from rat liver. 2-trans-Hexadecenoic acid as well as 9-cis-gexadecenoic acid (palmitoleic acid) were found to be formed as monoenoic acid in this system. (author)

Miniature Packaging Concept for LNAs in the 200-300 GHz Range

Science.gov (United States)

Samoska, Lorene; Fung, Andy; Varonen, Mikko; Lin, Robert; Peralta, Alejandro; Soria, Mary; Lee, Choonsup; Padmanabhan, Sharmila; Sarkozy, Stephen; Lai, Richard

2016-01-01

In this work, we describe new miniaturized low noise amplifier modules which we developed for incorporation in small-scale satellites or Cubesats, and which exhibit similar or better performance compared to previously reported LNAs in the literature. We have targeted the WR4 (170-260 GHz) and WR3 (220-325 GHz) waveguide bands for the module development. The modules include two different methods of E-plane probes which have been developed for low loss, and stability at high frequencies. MMIC LNAs were also developed for these frequency ranges and fabricated in Northrop Grumman Corporation's 35 nm InP HEMT technology, and we have experimentally verified that noise performance is lower than reported in prior work. The best results include a miniature LNA module with 550K noise at 224 GHz, and a wideband LNA module with 15 dB gain from 230-280 GHz.

Active Sensor for Microwave Tissue Imaging with Bias-Switched Arrays.

Science.gov (United States)

Foroutan, Farzad; Nikolova, Natalia K

2018-05-06

A prototype of a bias-switched active sensor was developed and measured to establish the achievable dynamic range in a new generation of active arrays for microwave tissue imaging. The sensor integrates a printed slot antenna, a low-noise amplifier (LNA) and an active mixer in a single unit, which is sufficiently small to enable inter-sensor separation distance as small as 12 mm. The sensor’s input covers the bandwidth from 3 GHz to 7.5 GHz. Its output intermediate frequency (IF) is 30 MHz. The sensor is controlled by a simple bias-switching circuit, which switches ON and OFF the bias of the LNA and the mixer simultaneously. It was demonstrated experimentally that the dynamic range of the sensor, as determined by its ON and OFF states, is 109 dB and 118 dB at resolution bandwidths of 1 kHz and 100 Hz, respectively.

A 0.1-1.4 GHz inductorless low-noise amplifier with 13 dBm IIP3 and 24 dBm IIP2 in 180 nm CMOS

Science.gov (United States)

Guo, Benqing; Chen, Jun; Chen, Hongpeng; Wang, Xuebing

2018-01-01

An inductorless noise-canceling CMOS low-noise amplifier (LNA) with wideband linearization technique is proposed. The complementary configuration by stacked NMOS/PMOS is employed to compensate second-order nonlinearity of the circuit. The third-order distortion of the auxiliary stage is also mitigated by that of the weak inversion transistors in the main path. The bias and scaling size combined by digital control words are further tuned to obtain enhanced linearity over the desired band. Implemented in a 0.18 μm CMOS process, simulated results show that the proposed LNA provides a voltage gain of 16.1 dB and a NF of 2.8-3.4 dB from 0.1 GHz to 1.4 GHz. The IIP3 and IIP2 of 13-18.9 and 24-40 dBm are obtained, respectively. The circuit core consumes 19 mW from a 1.8 V supply.

Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

Science.gov (United States)

Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

2002-12-06

Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

Glycosyltransferase glycosylating flavokermesic acid and/or kermesic acid

DEFF Research Database (Denmark)

2016-01-01

An isolated glycosyltransferase (GT) polypeptide capable of: (I) : conjugating glucose to flavokermesic acid (FK); and/or (II) : conjugating glucose to kermesic acid (KA) and use of this GT to e.g. make Carminic acid.......An isolated glycosyltransferase (GT) polypeptide capable of: (I) : conjugating glucose to flavokermesic acid (FK); and/or (II) : conjugating glucose to kermesic acid (KA) and use of this GT to e.g. make Carminic acid....

GLYCOSYLTRANSFERASE GLYCOSYLATING FLAVOKERMESIC ACID AND/OR KERMESIC ACID

DEFF Research Database (Denmark)

2015-01-01

An isolated glycosyltransferase (GT) polypeptide capable of: (I): conjugating glucose to flavokermesic acid (FK); and/or (II): conjugating glucose to kermesic acid (KA) and use of this GT to e.g. make Carminic acid.......An isolated glycosyltransferase (GT) polypeptide capable of: (I): conjugating glucose to flavokermesic acid (FK); and/or (II): conjugating glucose to kermesic acid (KA) and use of this GT to e.g. make Carminic acid....

Specific bile acid radioimmunoassays for separate determinations of unconjugated cholic acid, conjugated cholic acid and conjugated deoxycholic acid in serum and their clinical application

International Nuclear Information System (INIS)

Matern, S.; Gerok, W.

1977-01-01

Specific radioimmunoassays for separate determinations of serum unconjugated cholic, conjugated cholic and conjugated deoxycholic acids have been developed. Prior to the radioimmunoassay, extraction of serum bile acids was performed with Amberlite XAD-2. Unconjugated cholic acid was separated from glyco- and taurocholic acids by thin-layer chromatography. At 50% displacement of bound labeled glyco[ 3 H]cholic acid using antiserum obtained after immunization with cholic acid-bovine serum albumin-conjugate the cross-reactivity of taurocholic acid was 100%, cholic acid 80%, glycochenodeoxycholic acid 10%, chenodeoxycholic acid 7%, conjugated deoxycholic acid 3%, and conjugated lithocholic acid 3 H]cholic acid was linear on a logit-log plot from 5 to 80 pmol of unlabeled glycocholic acid. Fasting serum conjugated cholic acid in healthy subjects was 0.68 +- 0.34 μmol/l. Unconjugated cholic acid was determined by a solid phase radioimmunoassay using the cholic acid antibody chemically bound to Sepharose. The displacement curve of [ 3 H]cholic acid in the solid phase radioimmunoassay was linear on a logit-log plot from 5 to 200 pmol of unlabeled cholic acid. The coefficient of variation between samples was 5%. Fasting serum conjugated deoxycholic acid concentrations in 10 healthy subjects ranged from 0.18 to 0.92 μmol/l determined by a radioimmunoassay using antiserum obtained after immunization with deoxycholic acid-bovine serum albumin-conjugate. The clinical application of these bile acid radioimmunoassays is shown by an 'oral cholate tolerance test' as a sensitive indicator of liver function and by an 'oral cholyglycine tolerance test' as a useful test for bile acid absorption. (orig.) [de

Amino acids in the sedimentary humic and fulvic acids

Digital Repository Service at National Institute of Oceanography (India)

Sardessai, S.

acids in the coastal Arabian Sea sediments: whereas amino acids content of fulvic acids was lower than that of humic acids in the coastal sediments of Bay of Bengal. Slope sedimentary humic acids were relatively enriched in amino acids as compared...

Adaptive Nonlinear RF Cancellation for Improved Isolation in Simultaneous Transmit–Receive Systems

Science.gov (United States)

Kiayani, Adnan; Waheed, Muhammad Zeeshan; Anttila, Lauri; Abdelaziz, Mahmoud; Korpi, Dani; Syrjala, Ville; Kosunen, Marko; Stadius, Kari; Ryynanen, Jussi; Valkama, Mikko

2018-05-01

This paper proposes an active radio frequency (RF) cancellation solution to suppress the transmitter (TX) passband leakage signal in radio transceivers supporting simultaneous transmission and reception. The proposed technique is based on creating an opposite-phase baseband equivalent replica of the TX leakage signal in the transceiver digital front-end through adaptive nonlinear filtering of the known transmit data, to facilitate highly accurate cancellation under a nonlinear TX power amplifier (PA). The active RF cancellation is then accomplished by employing an auxiliary transmitter chain, to generate the actual RF cancellation signal, and combining it with the received signal at the receiver (RX) low noise amplifier (LNA) input. A closed-loop parameter learning approach, based on the decorrelation principle, is also developed to efficiently estimate the coefficients of the nonlinear cancellation filter in the presence of a nonlinear TX PA with memory, finite passive isolation, and a nonlinear RX LNA. The performance of the proposed cancellation technique is evaluated through comprehensive RF measurements adopting commercial LTE-Advanced transceiver hardware components. The results show that the proposed technique can provide an additional suppression of up to 54 dB for the TX passband leakage signal at the RX LNA input, even at considerably high transmit power levels and with wide transmission bandwidths. Such novel cancellation solution can therefore substantially improve the TX-RX isolation, hence reducing the requirements on passive isolation and RF component linearity, as well as increasing the efficiency and flexibility of the RF spectrum use in the emerging 5G radio networks.

Design of high–order HTS dual–band bandpass filters with receiver subsystem for future mobile communication systems

Energy Technology Data Exchange (ETDEWEB)

Sekiya, N., E-mail: nsekiya@yamanashi.ac.jp

2016-08-15

Highlights: • We have developed two high-order HTS dual-band BPFs with a receiver subsystem for future mobile communication systems. • We developed a method for flexibly adjusting the coupling coefficient for the two passbands. • We demonstrated an HTS dual-band BPF receiver subsystem that uses a pulse tube cryocooler and a wideband LNA. • The proposed BPF is evaluated by simulation and measurement with good agreement. - Abstract: We have developed two high-order high-temperature superconducting (HTS) dual-band bandpass filters (BPFs) with a receiver subsystem for future mobile communication systems. They feature stub-loaded hair-pin resonators with two types of microstrip lines between them. One has a six-pole design, and the other has an eight-pole design. Both were designed to operate at 2.15 GHz with a 43-MHz (2%) bandwidth for the lower passband and at 3.50 GHz with a 70-MHz (2%) bandwidth for the upper one. They were fabricated using YBa{sub 2}Cu{sub 3}O{sub y} thin film on a CeO{sub 2}-bufferd r-Al{sub 2}O{sub 3} substrate. The measured results for both filters agree well with the simulated ones. The HTS dual-band BPF receiver subsystem uses a pulse tube cryocooler and a wideband low noise amplifier (LNA). We measured the frequency response of the six-pole dual-band BPF with and without a wideband LNA with a gain of 10 dB. The measured return losses were close.

Effect of propionic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

Science.gov (United States)

Xu, Jian; Bao, Jia-Wei; Su, Xian-Feng; Zhang, Hong-Jian; Zeng, Xin; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

2016-03-01

In this study, an integrated citric acid-methane fermentation process was established to solve the problem of wastewater treatment in citric acid production. Citric acid wastewater was treated through anaerobic digestion and then the anaerobic digestion effluent (ADE) was further treated and recycled for the next batch citric acid fermentation. This process could eliminate wastewater discharge and reduce water resource consumption. Propionic acid was found in the ADE and its concentration continually increased in recycling. Effect of propionic acid on citric acid fermentation was investigated, and results indicated that influence of propionic acid on citric acid fermentation was contributed to the undissociated form. Citric acid fermentation was inhibited when the concentration of propionic acid was above 2, 4, and 6 mM in initial pH 4.0, 4.5 and, 5.0, respectively. However, low concentration of propionic acid could promote isomaltase activity which converted more isomaltose to available sugar, thereby increasing citric acid production. High concentration of propionic acid could influence the vitality of cell and prolong the lag phase, causing large amount of glucose still remaining in medium at the end of fermentation and decreasing citric acid production.

One-step multiplex quantitative RT-PCR for the simultaneous detection of viroids and phytoplasmas of pome fruit trees.

Science.gov (United States)

Malandraki, Ioanna; Varveri, Christina; Olmos, Antonio; Vassilakos, Nikon

2015-03-01

A one-step multiplex real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) based on TaqMan chemistry was developed for the simultaneous detection of Pear blister canker viroid and Apple scar skin viroid along with universal detection of phytoplasmas, in pome trees. Total nucleic acids (TNAs) extraction was performed according to a modified CTAB protocol. Primers and TaqMan MGB probes for specific detection of the two viroids were designed in this study, whereas for phytoplasma detection published universal primers and probe were used, with the difference that the later was modified to carry a MGB quencher. The pathogens were detected simultaneously in 10-fold serial dilutions of TNAs from infected plant material into TNAs of healthy plant up to dilutions 10(-5) for viroids and 10(-4) for phytoplasmas. The multiplex real-time assay was at least 10 times more sensitive than conventional protocols for viroid and phytoplasma detection. Simultaneous detection of the three targets was achieved in composite samples at least up to a ratio of 1:100 triple-infected to healthy tissue, demonstrating that the developed assay has the potential to be used for rapid and massive screening of viroids and phytoplasmas of pome fruit trees in the frame of certification schemes and surveys. Copyright © 2014 Elsevier B.V. All rights reserved.

A Direct, Biomass-Based Synthesis of Benzoic Acid: Formic Acid-Mediated Deoxygenation of the Glucose-Derived Materials Quinic Acid and Shikimic Acid

Energy Technology Data Exchange (ETDEWEB)

Arceo, Elena; Ellman, Jonathan; Bergman, Robert

2010-05-03

An alternative biomass-based route to benzoic acid from the renewable starting materials quinic acid and shikimic acid is described. Benzoic acid is obtained selectively using a highly efficient, one-step formic acid-mediated deoxygenation method.

A 24 GHz integrated SiGe BiCMOS vital signs detection radar front-end

DEFF Research Database (Denmark)

Jensen, Brian Sveistrup; Johansen, Tom K.; Zhurbenko, Vitaliy

2013-01-01

In this paper a 24 GHz integrated front-end transceiver for vital signs detection (VSD) radars is described. The heterodyne radar transceiver integrates LO buffering and quadrature splitting circuits, up- and down-conversion SSB mixers and two cascaded receiver LNA's. The chip has been manufactured...

Journal of Biosciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Previous studies have focused attention on their properties of duplex stabilities, hybridization kinetics and resistance against nuclease digestion; however, their ability to discriminate mismatched hybridizations has been explored much less. In this study, LNA- and OMeN-modified oligonucleotide probes have been prepared ...

Synthesis and biological evaluation of branched and conformationally restricted analogs of the anticancer compounds 3'-C-ethynyluridine (EUrd) and 3'-C-ethynylcytidine (ECyd)

DEFF Research Database (Denmark)

Hrdlicka, Patrick J; Andersen, Nicolai K; Jepsen, Jan S

2005-01-01

The synthesis of branched and conformationally restricted analogs of the anticancer nucleosides 3'-C-ethynyluridine (EUrd) and 3'-C-ethynylcytidine (ECyd) is presented. Molecular modeling and (1)H NMR coupling constant analysis revealed that the furanose rings of all analogs except the LNA analog...

Catalytic acetoxylation of lactic acid to 2-acetoxypropionic acid, en route to acrylic acid

NARCIS (Netherlands)

Beerthuis, R.; Granollers, M.; Brown, D.R.; Salavagione, H.J.; Rothenberg, G.; Shiju, N.R.

2015-01-01

We present an alternative synthetic route to acrylic acid, starting from the platform chemical lactic acid and using heterogeneous catalysis. To improve selectivity, we designed an indirect dehydration reaction that proceeds via acetoxylation of lactic acid to 2-acetoxypropionic acid. This

Gene expression of desaturase (FADS1 and FADS2) and Elongase (ELOVL5) enzymes in peripheral blood: association with polyunsaturated fatty acid levels and atopic eczema in 4-year-old children.

Science.gov (United States)

Chisaguano, Aida Maribel; Montes, Rosa; Pérez-Berezo, Teresa; Castellote, Ana Isabel; Guerendiain, Marcela; Bustamante, Mariona; Morales, Eva; García-Esteban, Raquel; Sunyer, Jordi; Franch, Angels; López-Sabater, M Carmen

2013-01-01

It is unknown if changes in the gene expression of the desaturase and elongase enzymes are associated with abnormal n-6 long chain polyunsaturated fatty acid (LC-PUFA) levels in children with atopic eczema (AE). We analyzed whether mRNA-expression of genes encoding key enzymes of LC-PUFA synthesis (FADS1, FADS2 and ELOVL5) is associated with circulating LC-PUFA levels and risk of AE in 4-year-old children. AE (n=20) and non-AE (n=104) children participating in the Sabadell cohort within the INfancia y Medio Ambiente (INMA) Project were included in the present study. RT-PCR with TaqMan Low-Density Array cards was used to measure the mRNA-expression of FADS1, FADS2 and ELOVL5. LC-PUFA levels were measured by fast gas chromatography in plasma phospholipids. The relationship of gene expression with LC-PUFA levels and enzyme activities was evaluated by Pearson's rank correlation coefficient, and logistic regression models were used to study its association with risk of developing AE. Children with AE had lower levels of several n-6 PUFA members, dihomo-γ-linolenic (DGLA) and arachidonic (AA) acids. mRNA-expression levels of FADS1 and 2 strongly correlated with DGLA levels and with D6D activity. FADS2 and ELOVL5 mRNA-expression levels were significantly lower in AE than in non-AE children (-40.30% and -20.36%; respectively), but no differences were found for FADS1. Changes in the mRNA-expression levels of FADS1 and 2 directly affect blood DGLA levels and D6D activity. This study suggests that lower mRNA-expressions of FADS2 and ELOVL5 are associated with higher risk of atopic eczema in young children.

Gene Expression of Desaturase (FADS1 and FADS2) and Elongase (ELOVL5) Enzymes in Peripheral Blood: Association with Polyunsaturated Fatty Acid Levels and Atopic Eczema in 4-Year-Old Children

Science.gov (United States)

Chisaguano, Aida Maribel; Montes, Rosa; Pérez-Berezo, Teresa; Castellote, Ana Isabel; Guerendiain, Marcela; Bustamante, Mariona; Morales, Eva; García-Esteban, Raquel; Sunyer, Jordi; Franch, Àngels; López-Sabater, M. Carmen

2013-01-01

Abstract Background It is unknown if changes in the gene expression of the desaturase and elongase enzymes are associated with abnormal n-6 long chain polyunsaturated fatty acid (LC-PUFA) levels in children with atopic eczema (AE). We analyzed whether mRNA-expression of genes encoding key enzymes of LC-PUFA synthesis (FADS1, FADS2 and ELOVL5) is associated with circulating LC-PUFA levels and risk of AE in 4-year-old children. Methods AE (n=20) and non-AE (n=104) children participating in the Sabadell cohort within the INfancia y Medio Ambiente (INMA) Project were included in the present study. RT-PCR with TaqMan Low-Density Array cards was used to measure the mRNA-expression of FADS1, FADS2 and ELOVL5. LC-PUFA levels were measured by fast gas chromatography in plasma phospholipids. The relationship of gene expression with LC-PUFA levels and enzyme activities was evaluated by Pearson’s rank correlation coefficient, and logistic regression models were used to study its association with risk of developing AE. Results Children with AE had lower levels of several n-6 PUFA members, dihomo-γ-linolenic (DGLA) and arachidonic (AA) acids. mRNA-expression levels of FADS1 and 2 strongly correlated with DGLA levels and with D6D activity. FADS2 and ELOVL5 mRNA-expression levels were significantly lower in AE than in non-AE children (-40.30% and -20.36%; respectively), but no differences were found for FADS1. Conclusions and Significance Changes in the mRNA-expression levels of FADS1 and 2 directly affect blood DGLA levels and D6D activity. This study suggests that lower mRNA-expressions of FADS2 and ELOVL5 are associated with higher risk of atopic eczema in young children. PMID:24167612

[Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis].

Science.gov (United States)

Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua

2016-03-01

Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis.

[Regulating acid stress resistance of lactic acid bacteria--a review].

Science.gov (United States)

Wu, Chongde; Huang, Jun; Zhou, Rongqing

2014-07-04

As cell factories, lactic acid bacteria are widely used in food, agriculture, pharmaceutical and other industries. Acid stress is one the important survival challenges encountered by lactic acid bacteria both in fermentation process and in the gastrointestinal tract. Recently, the development of systems biology and metabolic engineering brings unprecedented opportunity for further elucidating the acid tolerance mechanisms and improving the acid stress resistance of lactic acid bacteria. This review addresses physiological mechanisms of lactic acid bacteria during acid stress. Moreover, strategies to improve the acid stress resistance of lactic acid were proposed.

Preparation and characterization Al3+-bentonite Turen Malang for esterification fatty acid (palmitic acid, oleic acid and linoleic acid)

Science.gov (United States)

Abdulloh, Abdulloh; Aminah, Nanik Siti; Triyono, Mudasir, Trisunaryanti, Wega

2016-03-01

Catalyst preparation and characterization of Al3+-bentonite for esterification of palmitic acid, oleic acid and linoleic acid has been done. Al3+-bentonite catalyst was prepared from natural bentonite of Turen Malang through cation exchange reaction using AlCl3 solution. The catalysts obtained were characterized by XRD, XRF, pyridine-FTIR and surface area analyser using the BET method. Catalyst activity test of Al3+-bentonite for esterification reaction was done at 65°C using molar ratio of metanol-fatty acid of 30:1 and 0.25 g of Al3+-bentonite catalyst for the period of ½, 1, 2, 3, 4 and 5 hours. Based on the characterization results, the Al3+-bentonite Turen Malang catalyst has a d-spacing of 15.63 Ǻ, acid sites of Brönsted and Lewis respectively of 230.79 µmol/g and 99.39 µmol/g, surface area of 507.3 m2/g and the average of radius pore of 20.09 Å. GC-MS analysis results of the oil phase after esterification reaction showed the formation of biodiesel (FAME: Fatty acid methyl ester), namely methyl palmitate, methyl oleate and methyl linoleate. The number of conversions resulted in esterification reaction using Al3+-bentonite Turen Malang catalyst was 74.61%, 37.75%, and 20, 93% for the esterification of palmitic acid, oleic acid and linoleic acid respectively.

Reliable allele detection using SNP-based PCR primers containing Locked Nucleic Acid: application in genetic mapping

Directory of Open Access Journals (Sweden)

Trognitz Friederike

2007-02-01

Full Text Available Abstract Background The diploid, Solanum caripense, a wild relative of potato and tomato, possesses valuable resistance to potato late blight and we are interested in the genetic base of this resistance. Due to extremely low levels of genetic variation within the S. caripense genome it proved impossible to generate a dense genetic map and to assign individual Solanum chromosomes through the use of conventional chromosome-specific SSR, RFLP, AFLP, as well as gene- or locus-specific markers. The ease of detection of DNA polymorphisms depends on both frequency and form of sequence variation. The narrow genetic background of close relatives and inbreds complicates the detection of persisting, reduced polymorphism and is a challenge to the development of reliable molecular markers. Nonetheless, monomorphic DNA fragments representing not directly usable conventional markers can contain considerable variation at the level of single nucleotide polymorphisms (SNPs. This can be used for the design of allele-specific molecular markers. The reproducible detection of allele-specific markers based on SNPs has been a technical challenge. Results We present a fast and cost-effective protocol for the detection of allele-specific SNPs by applying Sequence Polymorphism-Derived (SPD markers. These markers proved highly efficient for fingerprinting of individuals possessing a homogeneous genetic background. SPD markers are obtained from within non-informative, conventional molecular marker fragments that are screened for SNPs to design allele-specific PCR primers. The method makes use of primers containing a single, 3'-terminal Locked Nucleic Acid (LNA base. We demonstrate the applicability of the technique by successful genetic mapping of allele-specific SNP markers derived from monomorphic Conserved Ortholog Set II (COSII markers mapped to Solanum chromosomes, in S. caripense. By using SPD markers it was possible for the first time to map the S. caripense alleles

Efficacy of Lactic Acid, Lactic Acid-Acetic Acid Blends, and Peracetic Acid To Reduce Salmonella on Chicken Parts under Simulated Commercial Processing Conditions.

Science.gov (United States)

Ramirex-Hernandez, Alejandra; Brashears, Mindy M; Sanchez-Plata, Marcos X

2018-01-01

The poultry processing industry has been undergoing a series of changes as it modifies processing practices to comply with new performance standards for chicken parts and comminuted poultry products. The regulatory approach encourages the use of intervention strategies to prevent and control foodborne pathogens in poultry products and thus improve food safety and protect human health. The present studies were conducted to evaluate the efficacy of antimicrobial interventions for reducing Salmonella on inoculated chicken parts under simulated commercial processing conditions. Chicken pieces were inoculated by immersion in a five-strain Salmonella cocktail at 6 log CFU/mL and then treated with organic acids and oxidizing agents on a commercial rinsing conveyor belt. The efficacy of spraying with six different treatments (sterile water, lactic acid, acetic acid, buffered lactic acid, acetic acid in combination with lactic acid, and peracetic acid) at two concentrations was evaluated on skin-on and skin-off chicken thighs at three application temperatures. Skinless chicken breasts were used to evaluate the antimicrobial efficacy of lactic acid and peracetic acid. The color stability of treated and untreated chicken parts was assessed after the acid interventions. The lactic acid and buffered lactic acid treatments produced the greatest reductions in Salmonella counts. Significant differences between the control and water treatments were identified for 5.11% lactic acid and 5.85% buffered lactic acid in both skin-on and skin-off chicken thighs. No significant effect of treatment temperature for skin-on chicken thighs was found. Lactic acid and peracetic acid were effective agents for eluting Salmonella cells attached to chicken breasts.

Molecular interaction of pinic acid with sulfuric acid

DEFF Research Database (Denmark)

Elm, Jonas; Kurtén, Theo; Bilde, Merete

2014-01-01

We investigate the molecular interactions between the semivolatile α-pinene oxidation product pinic acid and sulfuric acid using computational methods. The stepwise Gibbs free energies of formation have been calculated utilizing the M06-2X functional, and the stability of the clusters is evaluated...... cluster. The involvement of more than one pinic acid molecule in a single cluster is observed to lead to the formation of favorable (pinic acid)2(H2SO4) and (pinic acid)2(H2SO4)2 clusters. The identified most favorable growth paths starting from a single pinic acid molecule lead to closed structures...

Effect of acetic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

Science.gov (United States)

Xu, Jian; Chen, Yang-Qiu; Zhang, Hong-Jian; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

2014-09-01

An integrated citric acid-methane fermentation process was proposed to solve the problem of extraction wastewater in citric acid fermentation process. Extraction wastewater was treated by anaerobic digestion and then recycled for the next batch of citric acid fermentation to eliminate wastewater discharge and reduce water resource consumption. Acetic acid as an intermediate product of methane fermentation was present in anaerobic digestion effluent. In this study, the effect of acetic acid on citric acid fermentation was investigated and results showed that lower concentration of acetic acid could promote Aspergillus niger growth and citric acid production. 5-Cyano-2,3-ditolyl tetrazolium chloride (CTC) staining was used to quantify the activity of A. niger cells, and the results suggested that when acetic acid concentration was above 8 mM at initial pH 4.5, the morphology of A. niger became uneven and the part of the cells' activity was significantly reduced, thereby resulting in deceasing of citric acid production. Effects of acetic acid on citric acid fermentation, as influenced by initial pH and cell number in inocula, were also examined. The result indicated that inhibition by acetic acid increased as initial pH declined and was rarely influenced by cell number in inocula.

New Acid Combination for a Successful Sandstone Acidizing

Science.gov (United States)

Shafiq, M. U.; Mahmud, H. K. B.; Rezaee, R.

2017-05-01

With the development of new enhanced oil recovery techniques, sandstone acidizing has been introduced and played a pivotal role in the petroleum industry. Different acid combinations have been applied, which react with the formation, dissolve the soluble particles; thus increase the production of hydrocarbons. To solve the problems which occurred using current preflush sandstone acidizing technology (hydrochloric acid); a new acid combination has been developed. Core flooding experiments on sandstone core samples with dimensions 1.5 in. × 3 in. were conducted at a flow rate of 2 cm3/min. A series of hydrochloric-acetic acid mixtures with different ratios were tested under 150°F temperature. The core flooding experiments performed are aimed to dissolve carbonate, sodium, potassium and calcium particles from the core samples. These experiments are followed by few important tests which include, porosity-permeability, pH value, Inductively Coupled Plasma (ICP) analysis and Nuclear Magnetic Resonance (NMR measurements). All the results are compared with the results of conventional hydrochloric acid technology. NMR and porosity analysis concluded that the new acid combination is more effective in creating fresh pore spaces and thus increasing the reservoir permeability. It can be seen from the pore distribution before and after the acidizing. Prior applying acid; the large size of pores appears most frequently in the pore distribution while with the applied acid, it was found that the small pore size is most the predominant of the pore distribution. These results are validated using ICP analysis which shows the effective removal of calcium and other positive ions from the core sample. This study concludes that the combination of acetic-hydrochloric acid can be a potential candidate for the preflush stage of sandstone acidizing at high temperature reservoirs.

Application of citric acid in acid stimulation treatments

Energy Technology Data Exchange (ETDEWEB)

Alkhaldi, M.H.; Sarma, H.K. [Adelaide Univ., Adelaide (Australia); Nasr-el-Din, H.A. [Texas A and M Univ., College Station, TX (United States)

2009-07-01

A rotating disk apparatus was used to investigate mass transfer during the reaction of citric acid with calcite. The study evaluated the effects of initial acid concentrations, temperature, and disk rotational speed on the effective diffusion coefficient of citric acid. The diffusion coefficient was calculated at 25, 40, and 50 degrees C using various citric acid concentrations. The study indicated that the coefficient was a function of the interactions between calcium citrate precipitation and counter calcium ions. At high acid concentrations, the effects of calcium citrate precipitation and counter calcium ions were significant. The calculated citric acid diffusion coefficients were not comparable with measured effective diffusion coefficients using the rotating disk. At lower initial citric acid concentrations, the effects of both calcium citrate precipitation and counter calcium ions on citric acid diffusivity were minimal. It was concluded that temperature effects on the diffusion coefficient followed Arrhenius law. Activation energy was equal to 37.9 kJ/mol. 34 refs., 4 tabs., 13 figs.

Acid distribution in phosphoric acid fuel cells

Energy Technology Data Exchange (ETDEWEB)

Okae, I.; Seya, A.; Umemoto, M. [Fuji Electric Co., Ltd., Chiba (Japan)

1996-12-31

Electrolyte acid distribution among each component of a cell is determined by capillary force when the cell is not in operation, but the distribution under the current load conditions had not been clear so far. Since the loss of electrolyte acid during operation is inevitable, it is necessary to store enough amount of acid in every cell. But it must be under the level of which the acid disturbs the diffusion of reactive gases. Accordingly to know the actual acid distribution during operation in a cell is very important. In this report, we carried out experiments to clarify the distribution using small single cells.

Determination of dissociation constants or propionic acid and lactic acid (2-hydroxypropionic acid) by potentiometry and conductometry

International Nuclear Information System (INIS)

Saeeduddin; Khanzada, A.W.K.

2004-01-01

Dissociation constants of propionic acid and 2-hydroxypropionic acid (lactic acid) have been studied at different temperatures between 25 to 50 deg. C interval. Propionic acid is analyzed by conductometry while 2-hydroxypropionic acid is analyzed by potentiometry. Both investigated compounds are symmetrical carboxylic acids having same length of carbon chain but are markedly different in ionic behavior. We were interested to see how the hydroxyl group (-OH) induction in propionic acid affects on pKa values of 2-hydroxypropionic acid. We observed that as temperature increases pKa values increase. The increase is observed for both the investigated compounds. PKa values of 2-hydroxypropionic acid are lower as compared to propionic acid because of electron withdrawing (-OH). (author)

Investigating Public Perception of Occupational Therapy: An Environmental Scan of Three Media Outlets.

Science.gov (United States)

Walsh, Wendy E

Using a phenomenological approach, this study investigated visibility and perception of the profession of occupational therapy in three media outlets. Content analysis occurred on LexisNexis Academic (LNA), Google Images, and Twitter platforms. Analysis of LNA identified the prevalence of articles about occupational therapy in domestic newspapers and similar media avenues, MaxQDA qualitative software coded Google Images from a search on occupational therapy, and AnalyzeWords evaluated Twitter feeds of four health care professions for presence and tone in a social media context. Results indicate that although occupational therapy is 100 years old, its presence in news and online platforms could be stronger. This study suggests that a clear professional identity for occupational therapy practitioners must be strategically communicated through academic and social platforms. Such advocacy promotes the profession, meets the next iteration of occupational therapy's professional vision, and allows occupational therapy to remain a prominent and formidable stakeholder in today's health care marketplace. Copyright © 2018 by the American Occupational Therapy Association, Inc.

A Robust High-Performance GPS L1 Receiver with Single-stage Quadrature Redio-Frequency Circuit

Science.gov (United States)

Liu, Jianghua; Xu, Weilin; Wan, Qinq; Liu, Tianci

2018-03-01

A low power current reuse single-stage quadrature raido-frequency part (SQRF) is proposed for GPS L1 receiver in 180nm CMOS process. The proposed circuit consists of LNA, Mixer, QVCO, is called the QLMV cell. A two blocks stacked topology is adopted in this design. The parallel QVCO and mixer placed on the top forms the upper stacked block, and the LNA placed on the bottom forms the other stacked block. The two blocks share the current and achieve low power performance. To improve the stability, a float current source is proposed. The float current isolated the local oscillation signal and the input RF signal, which bring the whole circuit robust high-performance. The result shows conversion gain is 34 dB, noise figure is three dB, the phase noise is -110 dBc/Hz at 1MHz and IIP3 is -20 dBm. The proposed circuit dissipated 1.7mW with 1 V supply voltage.

Design of CMOS Tunable Image-Rejection Low-Noise Amplifier with Active Inductor

Directory of Open Access Journals (Sweden)

Ler Chun Lee

2008-01-01

Full Text Available A fully integrated CMOS tunable image-rejection low-noise amplifier (IRLNA has been designed using Silterra's industry standard 0.18 μm RF CMOS process. The notch filter is designed using an active inductor. Measurement results show that the notch filter designed using active inductor contributes additional 1.19 dB to the noise figure of the low-noise amplifier (LNA. A better result is possible if the active inductor is optimized. Since active inductors require less die area, the die area occupied by the IRLNA is not significantly different from a conventional LNA, which was designed for comparison. The proposed IRLNA exhibits S21 of 11.8 dB, S11 of −17.8 dB, S22 of −10.7 dB, and input 1 dB compression point of −12 dBm at 3 GHz

Acid Rain, pH & Acidity: A Common Misinterpretation.

Science.gov (United States)

Clark, David B.; Thompson, Ronald E.

1989-01-01

Illustrates the basis for misleading statements about the relationship between pH and acid content in acid rain. Explains why pH cannot be used as a measure of acidity for rain or any other solution. Suggests that teachers present acidity and pH as two separate and distinct concepts. (RT)

Chlorogenic acid and caffeic acid are absorbed in humans

NARCIS (Netherlands)

Olthof, Margreet R.; Hollman, Peter C H; Katan, Martijn B.

2001-01-01

Chlorogenic acid, an ester of caffeic acid and quinic acid, is a major phenolic compound in coffee; daily intake in coffee drinkers is 0.5-1 g. Chlorogenic acid and caffeic acid are antioxidants in vitro and might therefore contribute to the prevention of cardiovascular disease. However, data on the

Automated 5 ' nuclease PCR assay for identification of Salmonella enterica

DEFF Research Database (Denmark)

Hoorfar, Jeffrey; Ahrens, Peter; Rådström, P.

2000-01-01

-point fluorescence (FAM) signals for the samples and positive control (TET) signals (relative sensitivity [Delta Rn], >0.6). The diagnostic specificity of the method was assessed using 120 non-Salmonella strains, which all resulted in negative FAM signals (Delta Rn, less than or equal to 0.5). All 100 rough...... Salmonella strains tested resulted in positive FAM and TET signals. In addition, it was found that the complete PCR mixture, predispensed in microwell plates, could be stored for up to 3 months at -20 degrees C, Thus, the diagnostic TaqMan assay developed can be a useful and simple alternative method......A simple and ready-to-go test based on a 5' nuclease (TaqMan) PCR technique was developed for identification of presumptive Salmonella enterica isolates. The results were compared with those of conventional methods. The TaqMan assay was evaluated for its ability to accurately detect 210 S. enterica...

Determination of the species specificity of the primers for the detection of chicken and turkey meat by realtime PCR method

Directory of Open Access Journals (Sweden)

Lenka Maršálková

2014-07-01

Full Text Available The aim of this work was to use TaqMan Real-Time PCR for quantitative authentication of chicken and turkey meat. To meet this purpose, a specific pair of primers and TaqMan probe was used. The test was aimed at identifying the reaction cycle of turkey and chicken meat using by two sets of primers. With first set of primer designed for chicken we obtained the following results: Cp = 16.18 for 100% chicken DNA Cp = 29, 18 100% turkey DNA It was also amplified DNA of pig that exceeded the detection threshold fluorescence intensities in the 31.07 cycle (Cp = 31.07. Using primers designed for turkey we obtained the following results Cp = 31.16 for 100% CHDNA, Cp =16.18 100% TDNA. It was also amplified the 100% DNA of rabbit in 31.63 cycle (Cp = 31.63 and deer in cycle 32 (Cp = 32. The DNA of all other animal species was amplificated after more than 35 cycles (Cp >35. It follows that the second detection primer pair is specific enough to unrelated species of animals by 30 cycles of the reaction. Species authentication based on DNA analysis from this perspective overcomes all the shortcomings of proteins. At present, DNA analysis use different types of PCR. Is the most progressive Real-time PCR, which is suitable for the specific use of detection (primers and TaqMan probe. The TaqMan Real-time PCR is within the sensitivity and specificity, clearly one of the best methods for identifying the species of chicken and turkey meat. The specificity of this method, however, depends primarily on the specificity of the primers and TaqMan probe. The 30 cycle reaction was chosen by us as the threshold for specificity using primers for authentication chicken and turkey meat.

Comparison of Buffer Effect of Different Acids During Sandstone Acidizing

International Nuclear Information System (INIS)

Shafiq, Mian Umer; Mahmud, Hisham Khaled Ben; Hamid, Mohamed Ali

2015-01-01

The most important concern of sandstone matrix acidizing is to increase the formation permeability by removing the silica particles. To accomplish this, the mud acid (HF: HCl) has been utilized successfully for many years to stimulate the sandstone formations, but still it has many complexities. This paper presents the results of laboratory investigations of different acid combinations (HF: HCl, HF: H 3 PO 4 and HF: HCOOH). Hydrofluoric acid and fluoboric acid are used to dissolve clays and feldspar. Phosphoric and formic acids are added as a buffer to maintain the pH of the solution; also it allows the maximum penetration of acid into the core sample. Different tests have been performed on the core samples before and after the acidizing to do the comparative study on the buffer effect of these acids. The analysis consists of permeability, porosity, color change and pH value tests. There is more increase in permeability and porosity while less change in pH when phosphoric and formic acids were used compared to mud acid. From these results it has been found that the buffer effect of phosphoric acid and formic acid is better than hydrochloric acid. (paper)

Electrolytic nature of aqueous sulfuric acid. 2. Acidity.

Science.gov (United States)

Fraenkel, Dan

2012-09-27

In part 1 of this study, I reported that the Debye-Hückel limiting law and the smaller-ion shell (SiS) model of strong electrolyte solutions fit nicely with the experimental mean ionic activity coefficient (γ(±)) of aqueous sulfuric acid as a function of concentration and of temperature when the acid is assumed to be a strong 1-3 electrolyte. Here, I report that the SiS-derived activity coefficient of H(+), γ(H(+)), of the 1-3 acid is comparable to that of aqueous HCl. This agrees with titration curves showing, as well-known, that sulfuric acid in water is parallel in strength to aqueous HCl. The calculated pH is in good accord with the Hammett acidity function, H(0), of aqueous sulfuric acid at low concentration, and differences between the two functions at high concentration are discussed and explained. This pH-H(0) relation is consistent with the literature showing that the H(0) of sulfuric acid (in the 1-9 M range) is similar to those of HCl and the other strong mineral monoprotic acids. The titration of aqueous sulfuric acid with NaOH does not agree with the known second dissociation constant of 0.010 23; rather, the constant is found to be ~0.32 and the acid behaves upon neutralization as a strong diprotic acid practically dissociating in one step. A plausible reaction pathway is offered to explain how the acid may transform, upon base neutralization, from a dissociated H(4)SO(5) (as 3H(+) and HSO(5)(3-)) to a dissociated H(2)SO(4) even though the equilibrium constant of the reaction H(+) + HSO(5)(3-) ↔ SO(4)(2-) + H(2)O, at 25 °C, is 10(-37) (part 1).

Aspartic acid

Science.gov (United States)

... we eat. Aspartic acid is also called asparaginic acid. Aspartic acid helps every cell in the body work. It ... release Normal nervous system function Plant sources of aspartic acid include: avocado, asparagus, and molasses. Animal sources of ...

Incorporation and distribution of dihomo-gamma-linolenic acid, arachidonic acid, and eicosapentaenoic acid in cultured human keratinocytes

International Nuclear Information System (INIS)

Punnonen, K.; Puustinen, T.; Jansen, C.T.

1986-01-01

Human keratinocytes in culture were labelled with 14 C-dihomo-gamma-linolenic acid, 14 C-arachidonic acid or 14 C-eicosapentaenoic acid. All three eicosanoid precursor fatty acids were effectively incorporated into the cells. In phospholipids most of the radioactivity was recovered, in neutral lipids a substantial amount, and as free unesterified fatty acids only a minor amount. Most of the radioactivity was found in phosphatidylethanolamine which was also the major phospholipid as measured by phosphorous assay. The incorporation of dihomo-gamma-linolenic acid and arachidonic acid into lipid subfractions was essentially similar. Eicosapentaenoic acid was, however, much less effectively incorporated into phosphatidylinositol + phosphatidylserine and, correspondingly, more effectively into triacylglycerols as compared to the two other precursor fatty acids. Once incorporated, the distribution of all three precursor fatty acids was relatively stable, and only minor amounts of fatty acids were released into the culture medium during short term culture (two days). Our study demonstrates that eicosanoid precursor fatty acids are avidly taken up by human keratinocytes and esterified into membrane lipids. The clinical implication of this finding is that dietary manipulations might be employed to cause changes in the fatty acid composition of keratinocytes

High levels of microRNA-21 in the stroma of colorectal cancers predict short disease-free survival in stage II colon cancer patients

DEFF Research Database (Denmark)

Nielsen, Boye Schnack; Jørgensen, Stine; Fog, Jacob Ulrik

2011-01-01

Approximately 25% of all patients with stage II colorectal cancer will experience recurrent disease and subsequently die within 5 years. MicroRNA-21 (miR-21) is upregulated in several cancer types and has been associated with survival in colon cancer. In the present study we developed a robust...... in situ hybridization assay using high-affinity Locked Nucleic Acid (LNA) probes that specifically detect miR-21 in formalin-fixed paraffin embedded (FFPE) tissue samples. The expression of miR-21 was analyzed by in situ hybridization on 130 stage II colon and 67 stage II rectal cancer specimens. The mi...... relative to the nuclear density (TBR) obtained using a red nuclear stain. High TBR (and TB) estimates of miR-21 expression correlated significantly with shorter disease-free survival (p = 0.004, HR = 1.28, 95% CI: 1.06-1.55) in the stage II colon cancer patient group, whereas no significant correlation...

Wideband CMOS low noise amplifier including an active balun

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, D.M.W.; Nauta, Bram

2007-01-01

An inductorless LNA with active balun is proposed for multi-standard radio applications between 100MHz and 6GHz [1]. It exploits a combination of a common-gate (CG) stage and an common-source (CS) stage with replica biasing to maximize balanced operation, while simultaneously canceling the noise and

Pharmacogenetics of clopidogrel: comparison between a standard and a rapid genetic testing.

Science.gov (United States)

Saracini, Claudia; Vestrini, Anna; Galora, Silvia; Armillis, Alessandra; Abbate, Rosanna; Giusti, Betti

2012-06-01

CYP2C19 variant alleles are independent predictors of clopidogrel response variability and occurrence of major adverse cardiovascular events in high-risk vascular patients on clopidogrel therapy. Increasing evidence suggests a combination of platelet function testing with CYP2C19 genetic testing may be more effective in identifying high-risk individuals for alternative antiplatelet therapeutic strategies. A crucial point in evaluating the use of these polymorphisms in clinical practice, besides test accuracy, is the cost of the genetic test and rapid availability of the results. One hundred acute coronary syndrome patients were genotyped for CYP2C19*2,*3,*4,*5, and *17 polymorphisms with two platforms: Verigene(®) and the TaqMan(®) system. Genotyping results obtained by the classical TaqMan approach and the rapid Verigene approach showed a 100% concordance for all the five polymorphisms investigated. The Verigene system had shorter turnaround time with respect to TaqMan. The cost of reagents for TaqMan genotyping was lower than that for the Verigene system, but the effective manual staff involvement and the relative cost resulted in higher cost for TaqMan than for Verigene. The Verigene system demonstrated good performance in terms of turnaround time and cost for the evaluation of the clopidogrel poor metabolizer status, giving genetic information in suitable time (206 min) for a therapeutic strategy decision.

Uracil in formic acid hydrolysates of deoxyribonucleic acid

Science.gov (United States)

Schein, Arnold H.

1966-01-01

1. When DNA is hydrolysed with formic acid for 30min. at 175° and the hydrolysate is chromatographed on paper with propan-2-ol–2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with RF similar to that of uracil can be detected. Uracil was separated from this region and identified by its spectra in acid and alkali, and by its RF in several solvent systems. 2. Cytosine, deoxyribocytidine and deoxyribocytidylic acid similarly treated with formic acid all yielded uracil, as did a mixture of deoxyribonucleotides. 3. Approx. 4% of deoxyribonucleotide cytosine was converted into uracil by the formic acid treatment. ImagesFig. 1. PMID:5949371

Reactive extraction and recovery of levulinic acid, formic acid and furfural from aqueous solutions containing sulphuric acid

NARCIS (Netherlands)

Brouwer, Thomas; Blahusiak, Marek; Babic, Katarina; Schuur, Boelo

2017-01-01

Levulinic acid (LA) can be produced from lignocellulosic materials via hydroxylation followed by an acid-catalyzed conversion of hexoses. Inorganic homogeneous catalysts are mostly used, in particular sulphuric acid, yielding a mixture of LA with sulphuric acid, formic acid (FA) and furfural.

Well acidizing

Energy Technology Data Exchange (ETDEWEB)

Street, E H

1980-01-23

The apparatus relates in particular to a well-treating process in which an aqueous acid solution having a pH of < 2 is injected into a subterranean reservoir in a manner such that materials that contain ferric ions are present in the acid and, as the acid reacts within the reservoir and attains a pH exceeding 3, tend to be precipitated as ferric ion-containing solid materials that may plug the pores of the reservoir. Such a precipitation is prevented by dissolving in the acid solution an amount of 5-sulfosalicylic acid which is at least sufficient to sequester significant proportions of ferric ions when the pH of the acid is from 0.5 to 3 but is less than enough to cause a significant salting-out of solid materials, and an amount of citric acid which is at least sufficient to sequester significant proportions of ferric ions when the pH of the acid is from 3 to 6 but is less than enough to precipitate a significant amount of calcium citrate. The amount of the 5-sulfosalicylic acid may be from 0.01 to 0.05 moles/l and the amount of citric acid is from 0.001 to 0.009 moles/l. 11 claims.

Chemistry and electrochemistry in trifluoroacetic acid. Comparison with acetic acid

International Nuclear Information System (INIS)

Petit, Gerard

1972-01-01

As the trifluoroacetic acid is, with the acetic acid, one of most often used carboxylic acids as solvent, notably in organic chemistry, this research thesis addresses some relatively simple complexing and redox reactions to highlight the peculiar feature of this acid, and to explain its very much different behaviour with respect to acetic acid. The author develops the notion of acidity level in solvents of low dielectric constant. The second part addresses a specific solvent: BF 3 (CH 3 COOH) 2 . The boron trifluoride strengthens the acidity of acetic acid and modifies its chemical and physical-chemical properties. In the third part, the author compares solvent properties of CF 3 COOH and CH 3 COOH. Noticed differences explain why the trifluoroacetic acid is a more interesting reaction environment than acetic acid for reactions such as electrophilic substitutions or protein solubilisation [fr

Role of sialic acid in synaptosomal transport of amino acid transmitters

International Nuclear Information System (INIS)

Zaleska, M.M.; Erecinska, M.

1987-01-01

Active, high-affinity, sodium-dependent uptake of [ 14 C]-aminobutyric acid and of the acidic amino acid D-[ 3 H]-aspartate was inhibited by pretreatment of synaptosomes with neuraminidase from Vibrio cholerae. Inhibition was of a noncompetitive type and was related to the amount of sialic acid released. The maximum accumulation ratios of both amino acids (intracellular [amino acid]/extracellular [amino acid]) remained largely unaltered. Treatment with neuraminidase affected neither the synaptosomal energy levels nor the concentration of internal potassium. It is suggested that the γ-aminobutyric acid and acidic amino acid transporters are glycosylated and that sialic acid is involved in the operation of the carrier proteins directly and not through modification of driving forces responsible for amino acid uptake

Distillation Separation of Hydrofluoric Acid and Nitric Acid from Acid Waste Using the Salt Effect on Vapor-Liquid Equilibrium

Science.gov (United States)

Yamamoto, Hideki; Sumoge, Iwao

2011-03-01

This study presents the distillation separation of hydrofluoric acid with use of the salt effect on the vapor-liquid equilibrium for acid aqueous solutions and acid mixtures. The vapor-liquid equilibrium of hydrofluoric acid + salt systems (fluorite, potassium nitrate, cesium nitrate) was measured using an apparatus made of perfluoro alkylvinylether. Cesium nitrate showed a salting-out effect on the vapor-liquid equilibrium of the hydrofluoric acid-water system. Fluorite and potassium nitrate showed a salting-in effect on the hydrofluoric acid-water system. Separation of hydrofluoric acid from an acid mixture containing nitric acid and hydrofluoric acid was tested by the simple distillation treatment using the salt effect of cesium nitrate (45 mass%). An acid mixture of nitric acid (5.0 mol · dm-3) and hydrofluoric acid (5.0 mol · dm-3) was prepared as a sample solution for distillation tests. The concentration of nitric acid in the first distillate decreased from 5.0 mol · dm-3 to 1.13 mol · dm-3, and the concentration of hydrofluoric acid increased to 5.41 mol · dm-3. This first distillate was further distilled without the addition of salt. The concentrations of hydrofluoric acid and nitric acid in the second distillate were 7.21 mol · dm-3 and 0.46 mol · dm-3, respectively. It was thus found that the salt effect on vapor-liquid equilibrium of acid mixtures was effective for the recycling of acids from acid mixture wastes.

17,21-Secohopanoic acids, 25-norhopanoic acids, and 28-norhopanoic acids in source rocks and crude oils

Energy Technology Data Exchange (ETDEWEB)

Xueming Pan; Philp, R.P. [University of Oklahoma, Norman, OK (United States). School of Geology and Geophysics

2006-09-15

The presence of three families of hopanoic acids, 17,21-secohopanoic acids, 25-norhopanoic acids, and 28-norhopanoic acids, is discussed. Oils from West Siberia and tar balls from the Seychelles Islands were found to contain relatively high proportions of 17,21-secohopanoic acids. These acids have not been previously reported in any oils or source rocks. A heavily biodegraded West Siberian oil, was found to contain an homologous series of 25-norhopanoic acids co-occurring with the 25-norhopanes as previously reported in only a small number of oils from Campos Basin, Brazil. 28-Norhopanoic acids have been reported in various sediments and extracts of the Monterey Shale, but in this study their occurrence has been extended to oils, degraded oils, and tar balls sourced from the Monterey Shale. The primary purpose herein is to report the occurrence of these acids and possible relationships between the acids and corresponding hydrocarbons. (Author)

Process for the preparation of lactic acid and glyceric acid

Science.gov (United States)

Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

2008-12-02

Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

The bile acids, deoxycholic acid and ursodeoxycholic acid, regulate colonic epithelial wound healing.

Science.gov (United States)

Mroz, Magdalena S; Lajczak, Natalia K; Goggins, Bridie J; Keely, Simon; Keely, Stephen J

2018-03-01

The intestinal epithelium constitutes an innate barrier which, upon injury, undergoes self-repair processes known as restitution. Although bile acids are known as important regulators of epithelial function in health and disease, their effects on wound healing processes are not yet clear. Here we set out to investigate the effects of the colonic bile acids, deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA), on epithelial restitution. Wound healing in T 84 cell monolayers grown on transparent, permeable supports was assessed over 48 h with or without bile acids. Cell migration was measured in Boyden chambers. mRNA and protein expression were measured by RT-PCR and Western blotting. DCA (50-150 µM) significantly inhibited wound closure in cultured epithelial monolayers and attenuated cell migration in Boyden chamber assays. DCA also induced nuclear accumulation of the farnesoid X receptor (FXR), whereas an FXR agonist, GW4064 (10 µM), inhibited wound closure. Both DCA and GW4064 attenuated the expression of CFTR Cl - channels, whereas inhibition of CFTR activity with either CFTR- inh -172 (10 µM) or GlyH-101 (25 µM) also prevented wound healing. Promoter/reporter assays revealed that FXR-induced downregulation of CFTR is mediated at the transcriptional level. In contrast, UDCA (50-150 µM) enhanced wound healing in vitro and prevented the effects of DCA. Finally, DCA inhibited and UDCA promoted mucosal healing in an in vivo mouse model. In conclusion, these studies suggest bile acids are important regulators of epithelial wound healing and are therefore good targets for development of new drugs to modulate intestinal barrier function in disease treatment. NEW & NOTEWORTHY The secondary bile acid, deoxycholic acid, inhibits colonic epithelial wound healing, an effect which appears to be mediated by activation of the nuclear bile acid receptor, FXR, with subsequent downregulation of CFTR expression and activity. In contrast, ursodeoxycholic acid promotes

Effects of dietary conjugated linoleic acid and linoleic:linolenic acid ratio on polyunsaturated fatty acid status in laying hens.

Science.gov (United States)

Du, M; Ahn, D U; Sell, J L

2000-12-01

A study was conducted to determine the effects of dietary conjugated linoleic acid (CLA) and the ratio of linoleic:linolenic acid on long-chain polyunsaturated fatty acid status. Thirty-two 31-wk-old White Leghorn hens were randomly assigned to four diets containing 8.2% soy oil, 4.1% soy oil + 2.5% CLA (4.1% CLA source), 4.1% flax oil + 2.5% CLA, or 4.1% soy oil + 4.1% flax oil. Hens were fed the diets for 3 wk before eggs and tissues were collected for the study. Lipids were extracted from egg yolk and tissues, classes of egg yolk lipids were separated, and fatty acid concentrations of total lipids, triglyceride, phosphatidylethanolamine, and phosphatidylcholine were analyzed by gas chromatography. The concentrations of monounsaturated fatty acids and non-CLA polyunsaturated fatty acids were reduced after CLA feeding. The amount of arachidonic acid was decreased after CLA feeding in linoleic acid- and linolenic acid-rich diets, but amounts of eicosapentaenoic acid and docosahexaenoic acid were increased in the linolenic-rich diet, indicating that the synthesis or deposition of long-chain n-3 fatty acids was accelerated after CLA feeding. The increased docosahexaenoic acid and eicosapentaenoic acid contents in lipid may be compensation for the decreased arachidonic acid content. Dietary supplementation of linoleic acid increased n-6 fatty acid levels in lipids, whereas linolenic acid increased n-3 fatty acid levels. Results also suggest that CLA might not be elongated to synthesize long-chain fatty acids in significant amounts. The effect of CLA in reducing the level of n-6 fatty acids and promoting the level of n-3 fatty acids could be related to the biological effects of CLA.

Robust AlGaN/GaN MMIC Receiver Components

NARCIS (Netherlands)

Heijningen, M. van; Janssen, J.P.B.; Vliet, F.E. van

2009-01-01

Apart from delivering very high output powers, GaN can also be used to realize robust receiver components, such as Low Noise Amplifiersand Switches. This paper presents the designand measurement results of two GaN X-band switch and LNA MMICs, designed for integration in a radar front end. The switch

A wideband high-linearity RF receiver front-end in CMOS

NARCIS (Netherlands)

Arkesteijn, V.J.; Klumperink, Eric A.M.; Nauta, Bram

This paper presents a wideband high-linearity RF receiver-front-end, implemented in standard 0.18 μm CMOS technology. The design employs a noise-canceling LNA in combination with two passive mixers, followed by lowpass-filtering and amplification at IF. The achieved bandwidth is >2 GHz, with a noise

Classical bile acids in animals, beta-phocaecholic acid in ducks.

Science.gov (United States)

Jirsa, M; Klinot, J; Klinotová, E; Ubik, K; Kucera, K

1989-01-01

1. Bile samples of different animals were analysed and the percentage content of classical bile acids was determined. 2. Herbivorous birds mostly excreted a large proportion of chenodeoxycholic acid. 3. The anteater (Myrmecophaga tridactyla) excreted deoxycholic acid most probably as a primary bile acid. 4. In the bile of ducks (Anas platyrhynchos) a large amount of (23R)3 alpha, 7 alpha, 23-trihydroxy-5 beta-cholan-24-oic acid (beta-phocaecholic acid) was found.

Decontamination effectiveness of mixtures of citric acid, oxalic acid and EDTA

International Nuclear Information System (INIS)

Speranzini, R.A.

1990-01-01

An experimental study of the decontamination effectiveness of citric acid, oxalic acid and EDTA mixtures was conducted to assess whether oxalic acid could be removed from decontamination solutions to minimize corrosion. In loop experiments, radioactive specimens from two boiling water reactors and one pressurized water reactor were suspended in solutions of single acids or in mixtures of reagents at total reagent concentrations of less than 0.1 wt% under conditions similar to those used to decontaminate reactor systems. Rate constants for dissolution of oxides and decontamination factors were measured. Based on the results, it was concluded that under certain conditions, oxalic acid was the most effective reagent for the dissolution of oxides. It was also found, however, that conditions under which effective dissolution occurred in solutions of oxalic acid and/or citric acid were difficult to define and control. EDTA was found to be an effective reagent for dissolution of oxides such that rates of dissolution in EDTA containing solutions at 117 degrees Celsius were comparable to rates in oxalic acid containing solutions. At 90 degrees Celsius, EDTA acted synergistically with oxalic acid such that the rate of dissolution of oxides in citric-acid/oxalic-acid/EDTA solutions was higher than in citric-acid/EDTA solutions. The rates of dissolution of oxides were significantly reduced when 60 mg/kg of ferric ion was added to the citric-acid/oxalic-acid, citric-acid/EDTA and citric-acid/oxalic-acid/EDTA solutions. It was concluded that effective decontaminations of BWR and PWR systems could be achieved with mixtures of citric acid and EDTA

Radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid from human serum, with use of 125I-labeled ligands

International Nuclear Information System (INIS)

Maeentausta, O.; Jaenne, O.

1979-01-01

We describe a method for radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid in serum. In the method, 125 I-labeled bile acid conjugates are used as the tracers along with antibodies raised against individual bile acid-bovine serum albumin conjugates. Antibody-bound and free bile acids were separated by polyethylene glycol precipitation (final concentration, 125 g/L). The lowest measurable amounts of the bile acids, expressed as pmol/tube, were: cholic acid conjugates, 2; chenodeoxycholic acid conjugates, 0.5; and deoxycholic acid conjugates, 2. Analytical recovery of bile acids added to bile acid-free serum ranged from 85 to 110%; intra-assay and inter-assay CVs ranged from 8.3 to 5.3% and from 5.3 to 12.2%, respectively. Concentrations (mean +- SD) of the bile acid conjugates in serum from apparently healthy women and men (in μmol/L) were: cholic acid conjugates, 0.43 +- 0.17 (n=126); chenodeoxycholic acid conjugates, 0.47 +- 0.23 (n=111); and deoxycholic acid conjugates, 0.33 +- 0.11 (n=96). The values for primary bile acids were greatly increased in patients with various hepatobiliary diseases

A Comparative Study of the Radical-scavenging Activity of the Phenolcarboxylic Acids Caffeic Acid, p-Coumaric Acid, Chlorogenic Acid and Ferulic Acid, With or Without 2-Mercaptoethanol, a Thiol, Using the Induction Period Method

Directory of Open Access Journals (Sweden)

Seiichiro Fujisawa

2008-10-01

Full Text Available Phenolcarboxylic acid antioxidants do not act in vivo as radical-scavengers in isolation, but rather together with GSH (glutathione, a coantioxidant, they constitute an intricate antioxidant network. Caffeic acid, p-coumaric acid, ferulic acid and chlorogenic acid with or without 2-mercaptoethanol (ME, as a substitute for GSH, was investigated by the induction period (IP method for polymerization of methyl methacrylate (MMA initiated by thermal decomposition of 2,2'-azobisisobutyronitrile (AIBN, a source of alkyl radicals, R. and benzoyl peroxide (BPO, a source of peroxy radicals, PhCOO. using differential scanning calorimetry (DSC. Upon PhCOO. radical scavenging, the stoichiometric factors (n, number of free radical trapped by one mole of antioxidant for caffeic acid, ferulic acid, p-coumaric acid and chlorogenic acid were 2.4, 1.8, 1.7 and 0.9, whereas upon R. radical scavenging, the corresponding values were 1.3, 1.2, 1.0 and 0.8, respectively. Antioxidants with n values close to 2 suggest the stepwise formation of semiquinone radicals and quinones. By contrast, those with n values close to 1 suggest the formation of dimers after single-electron oxidation, possibly due to recombination of corresponding aryloxy radicals. The ratio of the rate constant of inhibition to that of propagation (kinh/kp declined in the order chlorogenic acid > p-coumaric acid > ferulic acid > caffeic acid. The ratio of the observed IP for the phenolcarboxylic acid/2-mercapto-ethanol (ME mixture (1:1 molar ratio (A to the calculated IP (the simple sum of phenol acid antioxidant and ME (B was investigated. Upon R. scavenging, the caffeic acid or p-coumaric acid/ME mixture was A/B > 1, particularly the former was 1.2, suggesting a synergic effect. By contrast, upon PhCOO. scavenging, the corresponding mixture was A/B < 1, particularly the latter was 0.7, suggesting an antagonistic effect. Upon both radicals scavenging, the A/B for the ferulic acid or chlorogenic acid

Catalyzed oxidation reactions. IV. Picolinic acid catalysis of chromic acid oxidations

International Nuclear Information System (INIS)

Rocek, J.; Peng, T.Y.

1977-01-01

Picolinic acid and several closely related acids are effective catalysts in the chromic acid oxidation of primary and secondary alcohols; the oxidation of other substrates is accelerated only moderately. The reaction is first order in chromium-(VI), alcohol, and picolinic acid; it is second order in hydrogen ions at low acidity and approaches acidity independence at high perchloric acid concentrations. A primary deuterium kinetic isotope effect is observed at high but not at low acidities. At low acidity the reaction has a considerably lower activation energy and more negative activation entropy than at higher acidities. The reactive intermediate in the proposed mechanism is a negatively charged termolecular complex formed from chromic acid, picolinic acid, and alcohol. The rate-limiting step of the reaction changes with the acidity of the solution. At higher acidities the intermediate termolecular complex is formed reversibly and the overall reaction rate is determined by the rate of its decomposition into reaction products; at low acidities the formation of the complex is irreversible and hence rate limiting. Picolinic acids with a substituent in the 6 position show a greatly reduced catalytic activity. This observation is interpreted as suggesting a square pyramidal or octahedral structure for the reactive chromium (VI) intermediate. The temperature dependence of the deuterium isotope effect has been determined and the significance of the observed large values for E/sub a//sup D/ - E/sub a//sup H/ and A/sup D//A/sup H/ is discussed

Targeted metabolomics analysis reveals the association between maternal folic acid supplementation and fatty acids and amino acids profiles in rat pups.

Science.gov (United States)

Liu, Zhipeng; Liu, Rui; Chou, Jing; Yu, Jiaying; Liu, Xiaowei; Sun, Changhao; Li, Ying; Liu, Liyan

2018-07-15

Maternal diet during pregnancy can influence offspring's health by affecting development and metabolism. This study aimed to analyze the influence of maternal folic acid (FA) supplementation on the metabolism of rat pups using targeted metabolomics. Twenty female rats were randomly assigned to a FA supplementation (FAS group, n = 10) or control group (n = 10), which were fed AIN93G diet with 2 or 10 mg/kg FA, respectively. We then measured amino acids and their derivatives, biogenic amines, and fatty acids in the female rats and their pups by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC/MS-MS) and gas chromatography-mass spectrometry (GC/MS-MS). In maternal rats, the significant changes of three metabolites (proline, γ-aminobutyric acid and esterified octadecatetraenoic acid, P acids (leucine, isoleucine, serine, proline) were obtained in FAS pups. Furthermore, there were the decreased esterified fatty acids (arachidonic acid, eicosapentaenoic acid, and docosatetraenoic acid) and free fatty acids (oleic acid, linoleic acid, γ-linolenic acid, octadecatetraenoic acid, arachidonic acid, eicosapentaenoic acid and selacholeic acid) in FAS pups. Metabolic changes in the FAS pups were characterized by changes in fatty acids and amino acids. These results suggested that FA supplementation during pregnancy influenced amino acids and fatty acids metabolism in rat pups. This study provides new insights into the regulation of amino acids and fatty acids metabolism during early life. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluation of clinical sensitivity and specificity of hepatitis B virus (HBV), hepatitis C virus, and human immunodeficiency Virus-1 by cobas MPX: Detection of occult HBV infection in an HBV-endemic area.

Science.gov (United States)

Ha, Jihye; Park, Younhee; Kim, Hyon-Suk

2017-11-01

Transfusion-transmitted infectious diseases remain a major concern for blood safety, particularly with hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV). Nucleic acid testing (NAT) in donor screening shortens the serologically negative window period and reduces virus transmission. The cobas MPX (Roche Molecular Systems, Inc., Branchburg, New Jersey) is a recently developed multiplex qualitative PCR system that enables the simultaneous detection of HBV, HCV, and HIV with improved sensitivity and throughput using cobas 6800 and 8800 instruments. The aim of this study was to conduct an evaluation of the clinical sensitivity and specificity of cobas MPX detection of HBV, HCV, and HIV in clinical specimens. Among samples referred for HBV, HCV, and HIV-1 quantification at Severance Hospital, Yonsei University College of Medicine, positive samples were selected to evaluate sensitivity. A total of 843 samples was tested using both cobas MPX and COBAS AmpliPrep/COBAS TaqMan Tests for HBV, HCV, and HIV-1 using the cobas 8800 system and a COBAS TaqMan 96 analyzer, respectively. Samples that showed discrepancies were confirmed by nested PCR. The cobas MPX achieved excellent sensitivity and specificity for the detection of HBV, HCV, and HIV-1 in clinical samples. We found that the lower limit of detection (LOD) of blood screening by NAT actually improves clinical sensitivity, and occult HBV infection prevalence among healthy employees of the hospital was rather high. Copyright © 2017 Elsevier B.V. All rights reserved.

Understanding Acid Rain

Science.gov (United States)

Damonte, Kathleen

2004-01-01

The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

Validation of a multi-analyte HPLC-DAD method for determination of uric acid, creatinine, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid and 2-methylhippuric acid in human urine.

Science.gov (United States)

Remane, Daniela; Grunwald, Soeren; Hoeke, Henrike; Mueller, Andrea; Roeder, Stefan; von Bergen, Martin; Wissenbach, Dirk K

2015-08-15

During the last decades exposure sciences and epidemiological studies attracts more attention to unravel the mechanisms for the development of chronic diseases. According to this an existing HPLC-DAD method for determination of creatinine in urine samples was expended for seven analytes and validated. Creatinine, uric acid, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid, and 2-methylhippuric acid were separated by gradient elution (formate buffer/methanol) using an Eclipse Plus C18 Rapid Resolution column (4.6mm×100mm). No interfering signals were detected in mobile phase. After injection of blank urine samples signals for the endogenous compounds but no interferences were detected. All analytes were linear in the selected calibration range and a non weighted calibration model was chosen. Bias, intra-day and inter-day precision for all analytes were below 20% for quality control (QC) low and below 10% for QC medium and high. The limits of quantification in mobile phase were in line with reported reference values but had to be adjusted in urine for homovanillic acid (45mg/L), niacinamide 58.5(mg/L), and indole-3-acetic acid (63mg/L). Comparison of creatinine data obtained by the existing method with those of the developed method showing differences from -120mg/L to +110mg/L with a mean of differences of 29.0mg/L for 50 authentic urine samples. Analyzing 50 authentic urine samples, uric acid, creatinine, hippuric acid, and 2-methylhippuric acid were detected in (nearly) all samples. However, homovanillic acid was detected in 40%, niacinamide in 4% and indole-3-acetic acid was never detected within the selected samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Removal of sulfamic acid from plutonium sulfamate--sulfamic acid solution

International Nuclear Information System (INIS)

Gray, L.W.

1978-10-01

Plutonium metal can be readily dissolved in aqueous solutions of sulfamic acid. When the plutonium sulfamate--sulfamic acid solutions are added to normal purex process streams, the sulfamate ion is oxidized by addition of sodium nitrite. This generates sodium sulfate which must be stored as radioactive waste. When recovery of ingrown 241 Am or storage of the dissolved plutonium must be considered, the sulfamate ion poses major and undesirable precipitation problems in the process streams. The present studies show that 40 to 80% of the sulfamate present in the dissolver solutions can be removed by precipitation as sulfamic acid by the addition of concentrated nitric acid. Addition of 64% nitric acid allows precipitation of 40 to 50% of the sulfamate; addition of 72% nitric acid allows precipitation of 50 to 60% of the sulfamate. If the solutions are chilled, additional sulfamic acid will precipitate. If the solutions are chilled to -10 0 C, about 70 to 80% of the orginal sulfamic acid in the dissolver will precipitate. A single, low-volume wash of the sulfamic acid crystals with concentrated nitric acid will decontaminate the crystals to a plutonium content of 5 dis/(min-gram)

76 FR 77383 - Amendment of Class C Airspace; Palm Beach International Airport, FL

Science.gov (United States)

2011-12-13

... benefit LNA traffic that primarily arrives from, or departs to, the west and east of the airport. The... Beach Approach to maneuver, provide better transit to the practice areas to the west and permit straight... above. The dispersal headings vary from 030 to 160 degrees and the southern most heading would exit...

Development of a novel concept for performing multiple assays on clinical samples using fluidic device

DEFF Research Database (Denmark)

Søe, Martin Jensen

RNA-130a sammenlignet med konventionelle teknikker, hvor der benyttes prober af DNA og LNA. Desuden kunne multiple miRNAer detekteres ved brug af sekventielle inkuberinger af TSA reagens. Dette tillod detektion af to miRNA og et protein på samme vævssnit. Den anden model involverede design og konstruktion...

Acid-functionalized polyolefin materials and their use in acid-promoted chemical reactions

Science.gov (United States)

Oyola, Yatsandra; Tian, Chengcheng; Bauer, John Christopher; Dai, Sheng

2016-06-07

An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted in liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.

Stream chemistry in the eastern United States. 2. Current sources of acidity in acidic and low acid-neutralizing-capacity streams

International Nuclear Information System (INIS)

Herlihy, A.T.; Kaufmann, P.R.; Mitch, M.E.

1991-01-01

The authors examined anion composition in National Stream Survey (NSS) data in order to evaluate the most probable sources of current acidity in acidic and low acid neutralizing capacity (ANC) streams in the eastern United States. Acidic streams that had almost no organic influence (less than 10% of total anions) and sulfate and nitrate concentrations indicative of evaporative concentration of atmospheric deposition were classified as acidic due to acidic deposition. These acidic streams were located in small forested watersheds in the Mid-Atlantic Highlands (an estimated 1950 km of stream length) and in the Mid-Atlantic Coastal Plain (1250 km). Acidic streams affected primarily by acidic deposition but also influenced by naturally occurring organic anions accounted for another 1180 km of acidic stream length and were located in the New Jersey Pine Barrens, plateau tops in the Mid-Atlantic and Southeast Highlands, and the Florida Panhandle. The total length of streams acidic due to acid mine drainage in the NSS (4590 km) was about the same as the total length of acidic streams likely affected by acidic deposition (4380 km). Acidic streams whose acid anion composition was dominated by organics were located in Florida and the Mid-Atlantic Coastal Plain. In Florida, most of the acidic streams were organic dominated, whereas about half of the streams in the Mid-Atlantic Coastal Plain were organic dominated. Organic-dominated acidic streams were not observed in the Mid-Atlantic and Southeast Highlands

15N NMR spectroscopic investigation of nitrous and nitric acids in sulfuric acid solutions of varying acidities

International Nuclear Information System (INIS)

Prakash, G.K.S.; Heiliger, L.; Olah, G.A.

1990-01-01

Both nitrous and nitric acids were studied in sulfuric acid solutions of varying acid strengths by 15 N NMR spectroscopy. The study gives new insights into the nature of intermediates present at different acid strengths. Furthermore, we have also discovered a novel redox reaction between NO 2 + and NO + ions involving the intermediacy of their respective acids. A mechanism is proposed to explain the observed results. 13 refs., 2 figs., 1 tab

Serum n-3 Tetracosapentaenoic Acid and Tetracosahexaenoic Acid Increase Following Higher Dietary α-Linolenic Acid but not Docosahexaenoic Acid.

Science.gov (United States)

Metherel, Adam H; Domenichiello, Anthony F; Kitson, Alex P; Lin, Yu-Hong; Bazinet, Richard P

2017-02-01

n-3 Tetracosapentaenoic acid (24:5n-3, TPAn-3) and tetracosahexaenoic acid (24:6n-3, THA) are believed to be important intermediates to docosahexaenoic acid (DHA, 22:6n-3) synthesis. The purpose of this study is to report for the first time serum concentrations of TPAn-3 and THA and their response to changing dietary α-linolenic acid (18:3n-3, ALA) and DHA. The responses will then be used in an attempt to predict the location of these fatty acids in relation to DHA in the biosynthetic pathway. Male Long Evans rats (n = 6 per group) were fed either a low (0.1% of total fatty acids), medium (3%) or high (10%) ALA diet with no added DHA, or a low (0%), medium (0.2%) or high (2%) DHA diet with a background of 2% ALA for 8 weeks post-weaning. Serum n-3 and n-6 polyunsaturated fatty acid (PUFA) concentrations (nmol/mL ± SEM) were determined by gas chromatography-mass spectrometry. Serum THA increases from low (0.3 ± 0.1) to medium (5.8 ± 0.7) but not from medium to high (4.6 ± 0.9) dietary ALA, while serum TPAn-3 increases with increasing dietary ALA from 0.09 ± 0.04 to 0.70 ± 0.09 to 1.23 ± 0.14 nmol/mL. Following DHA feeding, neither TPAn-3 or THA change across all dietary DHA intake levels. Serum TPAn-3 demonstrates a similar response to dietary DHA. In conclusion, this is the first study to demonstrate that increases in dietary ALA but not DHA increase serum TPAn-3 and THA in rats, suggesting that both fatty acids are precursors to DHA in the biosynthetic pathway.

Parabanic acid is the singlet oxygen specific oxidation product of uric acid.

Science.gov (United States)

Iida, Sayaka; Ohkubo, Yuki; Yamamoto, Yorihiro; Fujisawa, Akio

2017-11-01

Uric acid quenches singlet oxygen physically or reacts with it, but the oxidation product has not been previously characterized. The present study determined that the product is parabanic acid, which was confirmed by LC/TOFMS analysis. Parabanic acid was stable at acidic pH (acid at neutral or alkaline pH. The total yields of parabanic acid and oxaluric acid based on consumed uric acid were ~100% in clean singlet oxygen production systems such as UVA irradiation of Rose Bengal and thermal decomposition of 3-(1,4-dihydro-1,4-epidioxy-4-methyl-1-naphthyl)propionic acid. However, the ratio of the amount of uric acid consumed to the total amount of singlet oxygen generated was less than 1/180, indicating that most of the singlet oxygen was physically quenched. The total yields of parabanic acid and oxaluric acid were high in the uric acid oxidation systems with hydrogen peroxide plus hypochlorite or peroxynitrite. They became less than a few percent in peroxyl radical-, hypochlorite- or peroxynitrite-induced oxidation of uric acid. These results suggest that parabanic acid could be an in vivo probe of singlet oxygen formation because of the wide distribution of uric acid in human tissues and extracellular spaces. In fact, sunlight exposure significantly increased human skin levels of parabanic acid.

A GC-ECD method for estimation of free and bound amino acids, gamma-aminobutyric acid, salicylic acid, and acetyl salicylic acid from Solanum lycopersicum (L.).

Science.gov (United States)

Meher, Hari Charan; Gajbhiye, Vijay T; Singh, Ghanendra

2011-01-01

A gas chromatograph with electron capture detection method for estimation of selected metabolites--amino acids (free and bound), gamma-aminobutyric acid (GABA), salicylic acid (SA), and acetyl salicylic acid (ASA) from tomato--is reported. The method is based on nitrophenylation of the metabolites by 1-fluoro-2, 4-dinitrobenzene under aqueous alkaline conditions to form dinitophenyl derivatives. The derivatives were stable under the operating conditions of GC. Analysis of bound amino acids comprised perchloric acid precipitation of protein, alkylation (carboxymethylation) with iodoacetic acid, vapor-phase hydrolysis, and derivatization with 1-fluoro-2,4-dinitrobenzene in that order. The metabolites were resolved in 35 min, using a temperature-programmed run. The method is rapid, sensitive, and precise. It easily measured the typical amino acids (aspartate, asparagine, glutamate, glutamine, alanine, leucine, lysine, and phenylalanine) used for identification and quantification of a protein, resolved amino acids of the same mass (leucine and isoleucine), satisfactorily measured sulfur amino acid (methionine, cystine, and cysteine), and quantified GABA, SA, and ASA, as well. The developed method was validated for specificity, linearity, and precision. It has been applied and recommended for estimation of 25 metabolites from Solanum lycopersicum (L.).

Synthesis and anticonvulsant activity of novel bicyclic acidic amino acids

DEFF Research Database (Denmark)

Conti, Paola; De Amici, Marco; Joppolo Di Ventimiglia, Samuele

2003-01-01

Bicyclic acidic amino acids (+/-)-6 and (+/-)-7, which are conformationally constrained homologues of glutamic acid, were prepared via a strategy based on a 1,3-dipolar cycloaddition. The new amino acids were tested toward ionotropic and metabotropic glutamate receptor subtypes; both of them...

Crystal growth and physical characterization of picolinic acid cocrystallized with dicarboxylic acids

Science.gov (United States)

Somphon, Weenawan; Haller, Kenneth J.

2013-01-01

Pharmaceutical cocrystals are multicomponent materials containing an active pharmaceutical ingredient with another component in well-defined stoichiometry within the same unit cell. Such cocrystals are important in drug design, particularly for improving physicochemical properties such as solubility, bioavailability, or chemical stability. Picolinic acid is an endogenous metabolite of tryptophan and is widely used for neuroprotective, immunological, and anti-proliferative effects within the body. In this paper we present cocrystallization experiments of a series of dicarboxylic acids, oxalic acid, succinic acid, DL-tartaric acid, pimelic acid, and phthalic acid, with picolinic acid. Characterization by FT-IR and Raman spectroscopy, DSC and TG/DTG analysis, and X-ray powder diffraction show that new compounds are formed, including a 1:1 picolinium tartrate monohydrate, a 2:1 monohydrate adduct of picolinic acid and oxalic acid, and a 2:1 picolinic acid-succinic acid monohydrate cocrystal.

40 CFR 721.3620 - Fatty acid amine condensate, polycarboxylic acid salts.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acid amine condensate... Specific Chemical Substances § 721.3620 Fatty acid amine condensate, polycarboxylic acid salts. (a... a fatty acid amine condensate, polycarboxylic acid salts. (PMN P-92-445) is subject to reporting...

Bifidobacterium breve with α-linolenic acid and linoleic acid alters fatty acid metabolism in the maternal separation model of irritable bowel syndrome.

Science.gov (United States)

Barrett, Eoin; Fitzgerald, Patrick; Dinan, Timothy G; Cryan, John F; Ross, R Paul; Quigley, Eamonn M; Shanahan, Fergus; Kiely, Barry; Fitzgerald, Gerald F; O'Toole, Paul W; Stanton, Catherine

2012-01-01

The aim of this study was to compare the impact of dietary supplementation with a Bifidobacterium breve strain together with linoleic acid & α-linolenic acid, for 7 weeks, on colonic sensitivity and fatty acid metabolism in rats. Maternally separated and non-maternally separated Sprague Dawley rats (n = 15) were orally gavaged with either B. breve DPC6330 (10(9) microorganisms/day) alone or in combination with 0.5% (w/w) linoleic acid & 0.5% (w/w) α-linolenic acid, daily for 7 weeks and compared with trehalose and bovine serum albumin. Tissue fatty acid composition was assessed by gas-liquid chromatography and visceral hypersensitivity was assessed by colorectal distension. Significant differences in the fatty acid profiles of the non-separated controls and maternally separated controls were observed for α-linolenic acid and arachidonic acid in the liver, oleic acid and eicosenoic acid (c11) in adipose tissue, and for palmitoleic acid and docosahexaenoic acid in serum (pbreve DPC6330 to MS rats significantly increased palmitoleic acid, arachidonic acid and docosahexaenoic acid in the liver, eicosenoic acid (c11) in adipose tissue and palmitoleic acid in the prefrontal cortex (pbreve DPC6330 to non separated rats significantly increased eicosapentaenoic acid and docosapentaenoic acid in serum (pbreve DPC6330 in combination with linoleic acid and α-linolenic acid to maternally separated rats significantly increased docosapentaenoic acid in the serum (pbreve DPC6330 with fatty acid supplementation to non-separated rats significantly increased liver and serum docosapentaenoic acid (pbreve DPC6330 influenced host fatty acid metabolism. Administration of B. breve DPC6330 to maternally separated rats significantly modified the palmitoleic acid, arachidonic acid and docosahexaenoic acid contents in tissues. The effect was not observed in non-separated animals.

A novel approach in acidic disinfection through inhibition of acid resistance mechanisms; Maleic acid-mediated inhibition of glutamate decarboxylase activity enhances acid sensitivity of Listeria monocytogenes.

Science.gov (United States)

Paudyal, Ranju; Barnes, Ruth H; Karatzas, Kimon Andreas G

2018-02-01

Here it is demonstrated a novel approach in disinfection regimes where specific molecular acid resistance systems are inhibited aiming to eliminate microorganisms under acidic conditions. Despite the importance of the Glutamate Decarboxylase (GAD) system for survival of Listeria monocytogenes and other pathogens under acidic conditions, its potential inhibition by specific compounds that could lead to its elimination from foods or food preparation premises has not been studied. The effects of maleic acid on the acid resistance of L. monocytogenes were investigated and found that it has a higher antimicrobial activity under acidic conditions than other organic acids, while this could not be explained by its pKa or Ka values. The effects were found to be more pronounced on strains with higher GAD activity. Maleic acid affected the extracellular GABA levels while it did not affect the intracellular ones. Maleic acid had a major impact mainly on GadD2 activity as also shown in cell lysates. Furthermore, it was demonstrated that maleic acid is able to partly remove biofilms of L. monocytogenes. Maleic acid is able to inhibit the GAD of L. monocytogenes significantly enhancing its sensitivity to acidic conditions and together with its ability to remove biofilms, make a good candidate for disinfection regimes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acid Deposition Phenomena

International Nuclear Information System (INIS)

Ramadan, A.E.K.

2004-01-01

Acid deposition, commonly known as acid rain, occurs when emissions from the combustion of fossil fuels and other industrial processes undergo complex chemical reactions in the atmosphere and fall to the earth as wet deposition (rain, snow, cloud, fog) or dry deposition (dry particles, gas). Rain and snow are already naturally acidic, but are only considered problematic when less than a ph of 5.0 The main chemical precursors leading to acidic conditions are atmospheric concentrations of sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ). When these two compounds react with water, oxygen, and sunlight in the atmosphere, the result is sulfuric (H 2 SO 4 ) and nitric acids (HNO 3 ), the primary agents of acid deposition which mainly produced from the combustion of fossil fuel and from petroleum refinery. Airborne chemicals can travel long distances from their sources and can therefore affect ecosystems over broad regional scales and in locations far from the sources of emissions. According to the concern of petroleum ministry with the environment and occupational health, in this paper we will discussed the acid deposition phenomena through the following: Types of acidic deposition and its components in the atmosphere Natural and man-made sources of compounds causing the acidic deposition. Chemical reactions causing the acidic deposition phenomenon in the atmosphere. Factors affecting level of acidic deposition in the atmosphere. Impact of acid deposition. Procedures for acidic deposition control in petroleum industry

Bifidobacterium breve with α-linolenic acid and linoleic acid alters fatty acid metabolism in the maternal separation model of irritable bowel syndrome.

Directory of Open Access Journals (Sweden)

Eoin Barrett

Full Text Available The aim of this study was to compare the impact of dietary supplementation with a Bifidobacterium breve strain together with linoleic acid & α-linolenic acid, for 7 weeks, on colonic sensitivity and fatty acid metabolism in rats. Maternally separated and non-maternally separated Sprague Dawley rats (n = 15 were orally gavaged with either B. breve DPC6330 (10(9 microorganisms/day alone or in combination with 0.5% (w/w linoleic acid & 0.5% (w/w α-linolenic acid, daily for 7 weeks and compared with trehalose and bovine serum albumin. Tissue fatty acid composition was assessed by gas-liquid chromatography and visceral hypersensitivity was assessed by colorectal distension. Significant differences in the fatty acid profiles of the non-separated controls and maternally separated controls were observed for α-linolenic acid and arachidonic acid in the liver, oleic acid and eicosenoic acid (c11 in adipose tissue, and for palmitoleic acid and docosahexaenoic acid in serum (p<0.05. Administration of B. breve DPC6330 to MS rats significantly increased palmitoleic acid, arachidonic acid and docosahexaenoic acid in the liver, eicosenoic acid (c11 in adipose tissue and palmitoleic acid in the prefrontal cortex (p<0.05, whereas feeding B. breve DPC6330 to non separated rats significantly increased eicosapentaenoic acid and docosapentaenoic acid in serum (p<0.05 compared with the NS un-supplemented controls. Administration of B. breve DPC6330 in combination with linoleic acid and α-linolenic acid to maternally separated rats significantly increased docosapentaenoic acid in the serum (p<0.01 and α-linolenic acid in adipose tissue (p<0.001, whereas feeding B. breve DPC6330 with fatty acid supplementation to non-separated rats significantly increased liver and serum docosapentaenoic acid (p<0.05, and α-linolenic acid in adipose tissue (p<0.001. B. breve DPC6330 influenced host fatty acid metabolism. Administration of B. breve DPC6330 to maternally separated

Aminocaproic Acid and Tranexamic Acid Fail to Reverse Dabigatran-Induced Coagulopathy.

Science.gov (United States)

Levine, Michael; Huang, Margaret; Henderson, Sean O; Carmelli, Guy; Thomas, Stephen H

In recent years, dabigatran has emerged as a popular alternative to warfarin for treatment of atrial fibrillation. If rapid reversal is required, however, no reversal agent has clearly been established. The primary purpose of this manuscript was to evaluate the efficacy of tranexamic acid and aminocaproic acid as agents to reverse dabigatran-induced coagulopathy. Rats were randomly assigned to 6 groups. Each rat received either dabigatran or oral placebo, followed by saline, tranexamic acid, or aminocaproic acid. An activated clotting test was used to measure the coagulopathy. Neither tranexamic acid nor aminocaproic acid successfully reversed dabigatran-induced coagulopathy. In this rodent model of dabigatran-induced coagulopathy, neither tranexamic acid nor aminocaproic acid were able to reverse the coagulopathy.

Acidizing reservoirs while chelating iron with sulfosalicylic acid

Energy Technology Data Exchange (ETDEWEB)

McLaughlin, W A; Berkshire, D C

1980-09-30

A well treating process is described in which an aqueous solution of a strong acid capable of dissolving solids in a manner increasing the permeability of a subterranean earth formation is injected into a subterranean reservoir that contains an asphaltenic oil. At least the first injected portion of the aqueous acid and a solution or homogeneous dispersion of at least enough 5-sulfosalicylic acid to chelate with and prevent the formation of iron-asphaltene solids are included with substantially all of the ferric ions that become dissolved within the strong acid solution that enters the earth formation. 10 claims.

Acids and bases solvent effects on acid-base strenght

CERN Document Server

Cox, Brian G

2013-01-01

Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter- ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented.

Alkyl phosphonic acids and sulfonic acids in the Murchison meteorite

Science.gov (United States)

Cooper, George W.; Onwo, Wilfred M.; Cronin, John R.

1992-01-01

Homologous series of alkyl phosphonic acids and alkyl sulfonic acids, along with inorganic orthophosphate and sulfate, are identified in water extracts of the Murchison meteorite after conversion to their t-butyl dimethylsilyl derivatives. The methyl, ethyl, propyl, and butyl compounds are observed in both series. Five of the eight possible alkyl phosphonic acids and seven of the eight possible alkyl sulfonic acids through C4 are identified. Abundances decrease with increasing carbon number as observed of other homologous series indigenous to Murchison. Concentrations range downward from approximately 380 nmol/gram in the alkyl sulfonic acid series, and from 9 nmol/gram in the alkyl phosphonic acid series.

21 CFR 172.350 - Fumaric acid and salts of fumaric acid.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Fumaric acid and salts of fumaric acid. 172.350... HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.350 Fumaric acid and salts of fumaric acid. Fumaric acid and its calcium, ferrous, magnesium, potassium, and sodium salts may be safely used...

L-arginine prevents xanthoma development and inhibits atherosclerosis in LDL receptor knockout mice.

Science.gov (United States)

Aji, W; Ravalli, S; Szabolcs, M; Jiang, X C; Sciacca, R R; Michler, R E; Cannon, P J

1997-01-21

The potential antiatherosclerotic actions of NO were investigated in four groups of mice (n = 10 per group) lacking functional LDL receptor genes, an animal model of familial hypercholesterolemia. Group 1 was fed a regular chow diet. Groups 2 through 4 were fed a 1.25% high-cholesterol diet. In addition, group 3 received supplemental L-arginine and group 4 received L-arginine and N omega-nitro-L-arginine (L-NA), an inhibitor of NO synthase (NOS). Animals were killed at 6 months; aortas were stained with oil red O for planimetry and with antibodies against constitutive and inducible NOSs. Plasma cholesterol was markedly increased in the animals receiving the high-cholesterol diet. Xanthomas appeared in all mice fed the high-cholesterol diet alone but not in those receiving L-arginine. Aortic atherosclerosis was present in all mice on the high-cholesterol diet. The mean atherosclerotic lesion area was reduced significantly (P < .01) in the cholesterol-fed mice given L-arginine compared with those receiving the high-cholesterol diet alone. The mean atherosclerotic lesion area was significantly larger (P < .01) in cholesterol-fed mice receiving L-arginine + L-NA than in those on the high-cholesterol diet alone. Within the atherosclerotic plaques, endothelial cells immunoreacted for endothelial cell NOS; macrophages, foam cells, and smooth muscle cells immunostained strongly for inducible NOS and nitrotyrosine residues. The data indicate that L-arginine prevents xanthoma formation and reduces atherosclerosis in LDL receptor knockout mice fed a high-cholesterol diet. The abrogation of the beneficial effects of L-arginine by L-NA suggests that the antiatherosclerotic actions of L-arginine are mediated by NOS. The data suggest that L-arginine may be beneficial in familial hypercholesterolemia.

HHV-8 infection in patients with AIDS-related Kaposi's sarcoma in Brazil

Directory of Open Access Journals (Sweden)

Keller R.

2001-01-01

Full Text Available The aims of the present study were to determine the prevalence of human herpesvirus type 8 (HHV-8 in HIV-positive Brazilian patients with (HIV+/KS+ and without Kaposi's sarcoma (HIV+/KS- using PCR and immunofluorescence assays, to assess its association with KS disease, to evaluate the performance of these tests in detecting HHV-8 infection, and to investigate the association between anti-HHV-8 antibody titers, CD4 counts and staging of KS disease. Blood samples from 66 patients, 39 HIV+/KS+ and 27 HIV+/KS-, were analyzed for HHV-8 viremia in peripheral blood mononuclear cells by PCR and HHV-8 antigenemia for latent and lytic infection by immunofluorescence assay. Positive samples for latent nuclear HHV-8 antigen (LNA antibodies were titrated out from 1/100 to 1/409,600 dilution. Clinical information was collected from medical records and risk behavior was assessed through an interview. HHV-8 DNA sequences were detected by PCR in 74.3% of KS+ patients and in 3.7% of KS- patients. Serological assays were similar in detecting anti-LNA antibodies and anti-lytic antigens in sera from KS+ patients (79.5% and KS- patients (18.5%. HHV-8 was associated with KS whatever the method used, i.e., PCR (odds ratio (OR = 7.4, 95% confidence interval (CI = 2.16-25.61 or anti-LNA and anti-lytic antibodies (OR = 17.0, 95%CI = 4.91-59.14. Among KS+ patients, HHV-8 titration levels correlated positively with CD4 counts (rho 0.48, P = 0.02, but not with KS staging. HHV-8 is involved in the development of KS in different geographic areas worldwide, as it is in Brazil, where HHV-8 is more frequent among HIV+ patients. KS severity was associated with immunodeficiency, but no correlation was found between HHV-8 antibody titers and KS staging.

Design and analysis of high gain and low noise figure CMOS low noise amplifier for Q-band nano-sensor application

Science.gov (United States)

Suganthi, K.; Malarvizhi, S.

2018-03-01

A high gain, low power, low Noise figure (NF) and wide band of milli-meter Wave (mmW) circuits design at 50 GHz are used for Radio Frequency (RF) front end. The fundamental necessity of a receiver front-end includes perfect output and input impedance matching and port-to-port isolation with high gain and low noise over the entire band of interest. In this paper, a design of Cascade-Cascode CMOS LNA circuit at 50 GHz for Q-band application is proposed. The design of Low noise amplifier at 50 GHz using Agilent ADS tool with microstrip lines which provides simplicity in fabrication and less chip area. The low off-leakage current Ioff can be maintained with high K-dielectrics CMOS structure. Nano-scale electronics can be achieved with increased robustness. The design has overall gain of 11.091 dB and noise figure of 2.673 dB for the Q-band of 48.3 GHz to 51.3 GHz. Impedance matching is done by T matching network and the obtained input and output reflection coefficients are S11 = <-10 dB and S22 = <-10 dB. Compared to Silicon (Si) material, Wide Band Gap semiconductor materials used attains higher junction temperatures which is well matched to ceramics used in packaging technology, the protection and reliability also can be achieved with the electronic packaging. The reverse transmission coefficient S21 is less than -21 dB has shown that LNA has better isolation between input and output, Stability factor greater than 1 and Power is also optimized in this design. Layout is designed, power gain of 4.6 dB is achieved and area is optimized which is nearly equal to 502 740 μm2. The observed results show that the proposed Cascade-Cascode LNA design can find its suitability in future milli-meter Wave Radar application.

A Low Noise Electronic Circuit

NARCIS (Netherlands)

Annema, Anne J.; Leenaerts, Dominicus M.W.; de Vreede, Petrus W.H.

2002-01-01

An electronic circuit, which can be used as a Low Noise Amplifier (LNA), comprises two complementary Field Effect Transistors (M1, M2; M5, M6), each having a gate, a source and a drain. The gates are connected together as a common input terminal, and the drains are connected together as a

Low noise InP-based MMIC receivers for W-band

Science.gov (United States)

Leonard, Regis F.

1991-01-01

A program to develop a monolithic W-band low noise amplifier (a critical element in any W-band communications, sensors, or radar application) is described. Goals of the program include a completely monolithic low noise amplifier, less than a 3.5 dB noise figure, and a monolithic mixer suitable for integration with the LNA.

Heart and bile acids - Clinical consequences of altered bile acid metabolism.

Science.gov (United States)

Vasavan, Tharni; Ferraro, Elisa; Ibrahim, Effendi; Dixon, Peter; Gorelik, Julia; Williamson, Catherine

2018-04-01

Cardiac dysfunction has an increased prevalence in diseases complicated by liver cirrhosis such as primary biliary cholangitis and primary sclerosing cholangitis. This observation has led to research into the association between abnormalities in bile acid metabolism and cardiac pathology. Approximately 50% of liver cirrhosis cases develop cirrhotic cardiomyopathy. Bile acids are directly implicated in this, causing QT interval prolongation, cardiac hypertrophy, cardiomyocyte apoptosis and abnormal haemodynamics of the heart. Elevated maternal serum bile acids in intrahepatic cholestasis of pregnancy, a disorder which causes an impaired feto-maternal bile acid gradient, have been associated with fatal fetal arrhythmias. The hydrophobicity of individual bile acids in the serum bile acid pool is of relevance, with relatively lipophilic bile acids having a more harmful effect on the heart. Ursodeoxycholic acid can reverse or protect against these detrimental cardiac effects of elevated bile acids. Copyright © 2018 Elsevier B.V. All rights reserved.

Docosahexaenoic Acid-Derived Fatty Acid Esters of Hydroxy Fatty Acids (FAHFAs) With Anti-inflammatory Properties.

Science.gov (United States)

Kuda, Ondrej; Brezinova, Marie; Rombaldova, Martina; Slavikova, Barbora; Posta, Martin; Beier, Petr; Janovska, Petra; Veleba, Jiri; Kopecky, Jan; Kudova, Eva; Pelikanova, Terezie; Kopecky, Jan

2016-09-01

White adipose tissue (WAT) is a complex organ with both metabolic and endocrine functions. Dysregulation of all of these functions of WAT, together with low-grade inflammation of the tissue in obese individuals, contributes to the development of insulin resistance and type 2 diabetes. n-3 polyunsaturated fatty acids (PUFAs) of marine origin play an important role in the resolution of inflammation and exert beneficial metabolic effects. Using experiments in mice and overweight/obese patients with type 2 diabetes, we elucidated the structures of novel members of fatty acid esters of hydroxy fatty acids-lipokines derived from docosahexaenoic acid (DHA) and linoleic acid, which were present in serum and WAT after n-3 PUFA supplementation. These compounds contained DHA esterified to 9- and 13-hydroxyoctadecadienoic acid (HLA) or 14-hydroxydocosahexaenoic acid (HDHA), termed 9-DHAHLA, 13-DHAHLA, and 14-DHAHDHA, and were synthesized by adipocytes at concentrations comparable to those of protectins and resolvins derived from DHA in WAT. 13-DHAHLA exerted anti-inflammatory and proresolving properties while reducing macrophage activation by lipopolysaccharides and enhancing the phagocytosis of zymosan particles. Our results document the existence of novel lipid mediators, which are involved in the beneficial anti-inflammatory effects attributed to n-3 PUFAs, in both mice and humans. © 2016 by the American Diabetes Association.

Development of Real-Time PCR Methods for the Detection of Bacterial Meningitis Pathogens without DNA Extraction.

Directory of Open Access Journals (Sweden)

Jeni Vuong

Full Text Available Neisseria meningitidis (Nm, Haemophilus influenzae (Hi, and Streptococcus pneumoniae (Sp are the lead causes of bacterial meningitis. Detection of these pathogens from clinical specimens using traditional real-time PCR (rt-PCR requires DNA extraction to remove the PCR inhibitors prior to testing, which is time consuming and labor intensive. In this study, five species-specific (Nm-sodC and -ctrA, Hi-hpd#1 and -hpd#3 and Sp-lytA and six serogroup-specific rt-PCR tests (A, B, C, W, X, Y targeting Nm capsular genes were evaluated in the two direct rt-PCR methods using PerfeCTa and 5x Omni that do not require DNA extraction. The sensitivity and specify of the two direct rt-PCR methods were compared to TaqMan traditional rt-PCR, the current standard rt-PCR method for the detection of meningitis pathogens. The LLD for all 11 rt-PCR tests ranged from 6,227 to 272,229 CFU/ml for TaqMan, 1,824-135,982 for 5x Omni, and 168-6,836 CFU/ml for PerfeCTa. The diagnostic sensitivity using TaqMan ranged from 89.2%-99.6%, except for NmB-csb, which was 69.7%. For 5x Omni, the sensitivity varied from 67.1% to 99.8%, with three tests below 90%. The sensitivity of these tests using PerfeCTa varied from 89.4% to 99.8%. The specificity ranges of the 11 tests were 98.0-99.9%, 97.5-99.9%, and 92.9-99.9% for TaqMan, 5x Omni, and PerfeCTa, respectively. PerfeCTa direct rt-PCR demonstrated similar or better sensitivity compared to 5x Omni direct rt-PCR or TaqMan traditional rt-PCR. Since the direct rt-PCR method does not require DNA extraction, it reduces the time and cost for processing CSF specimens, increases testing throughput, decreases the risk of cross-contamination, and conserves precious CSF. The direct rt-PCR method will be beneficial to laboratories with high testing volume.

Bayesian inference for hybrid discrete-continuous stochastic kinetic models

International Nuclear Information System (INIS)

Sherlock, Chris; Golightly, Andrew; Gillespie, Colin S

2014-01-01

We consider the problem of efficiently performing simulation and inference for stochastic kinetic models. Whilst it is possible to work directly with the resulting Markov jump process (MJP), computational cost can be prohibitive for networks of realistic size and complexity. In this paper, we consider an inference scheme based on a novel hybrid simulator that classifies reactions as either ‘fast’ or ‘slow’ with fast reactions evolving as a continuous Markov process whilst the remaining slow reaction occurrences are modelled through a MJP with time-dependent hazards. A linear noise approximation (LNA) of fast reaction dynamics is employed and slow reaction events are captured by exploiting the ability to solve the stochastic differential equation driving the LNA. This simulation procedure is used as a proposal mechanism inside a particle MCMC scheme, thus allowing Bayesian inference for the model parameters. We apply the scheme to a simple application and compare the output with an existing hybrid approach and also a scheme for performing inference for the underlying discrete stochastic model. (paper)

A wideband large dynamic range and high linearity RF front-end for U-band mobile DTV

International Nuclear Information System (INIS)

Liu Rongjiang; Liu Shengyou; Guo Guiliang; Cheng Xu; Yan Yuepeng

2013-01-01

A wideband large dynamic range and high linearity U-band RF front-end for mobile DTV is introduced, and includes a noise-cancelling low-noise amplifier (LNA), an RF programmable gain amplifier (RFPGA) and a current communicating passive mixer. The noise/distortion cancelling structure and RC post-distortion compensation are employed to improve the linearity of the LNA. An RFPGA with five stages provides large dynamic range and fine gain resolution. A simple resistor voltage network in the passive mixer decreases the gate bias voltage of the mixing transistor, and optimum linearity and symmetrical mixing is obtained at the same time. The RF front-end is implemented in a 0.25 μm CMOS process. Tests show that it achieves an IIP3 (third-order intercept point) of −17 dBm, a conversion gain of 39 dB, and a noise figure of 5.8 dB. The RFPGA achieves a dynamic range of −36.2 to 23.5 dB with a resolution of 0.32 dB. (semiconductor integrated circuits)

Studies on the complexes of uranium(IV), thorium(IV) and lanthanum(III) acetates with p-aminobenzoic acid, m-aminobenzoic acid, benzilic acid and phthalic acid

International Nuclear Information System (INIS)

Singh, Mangal; Singh, Ajaib

1979-01-01

Complexes of acetates of U(IV), Th(IV) and La(III) with the ligands p-aminobenzoic acid, m-aminobenzoic acid, benzilic acid and phthalic acid have been prepared. Colour and chemical analytical data are recorded. They are characterised on the basis of IR and reflectance spectra and magnetic susceptibility data. (M.G.B.)

Incorporation of oxygen into abscisic acid and phaseic acid for molecular oxygen

International Nuclear Information System (INIS)

Creelman, R.A.; Zeevaart, J.A.D.

1984-01-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumariu. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% 18 O 2 and 80% N 2 indicates that one atom of 18 O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase. Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing 18 O 2 indicates that one atom of 18 O is presented in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-streesed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggest that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress. 17 references, 2 figures, 1 tables

Incorporation of oxygen into abscisic Acid and phaseic Acid from molecular oxygen.

Science.gov (United States)

Creelman, R A; Zeevaart, J A

1984-05-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% (18)O(2) and 80% N(2) indicates that one atom of (18)O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase.Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing (18)O(2) indicates that one atom of (18)O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress.

Amino acid and fatty acid compositions of Rusip from fermented Anchovy fish (Stolephorussp)

Science.gov (United States)

Koesoemawardani, D.; Hidayati, S.; Subeki

2018-04-01

Rusip is a typical food of Bangka Belitung Indonesia made from fermented anchovy. This study aims to determine the properties of chemistry, microbiology, composition of amino acids and fatty acids from fermented fish spontaneously and non spontaneously. Spontaneous rusip treatment is done by anchovy fish (Stolephorussp) after cleaning and added salt 25% (w/w) and palm sugar 10% (w/w). While, non-spontaneous rusip is done by adding a culture mixture of Streptococcus, Leuconostoc, and Lactobacillus bacteria 2% (w/v). The materials are then incubated for 2 weeks. The data obtained were then performed t-test at the level of 5%. Spontaneous and non-spontaneous rusip fermentation process showed significant differences in total acid, reducing sugar, salt content, TVN, total lactic acid bacteria, total mold, and total microbial. The dominant amino acid content of spontaneous and non-spontaneous rusip are glutamic acid and aspartic acid, while the dominant fatty acids in spontaneous and non-spontaneous rusip are docosahexaenoic acid, palmitic acid, oleic acid, arachidonic acid, stearic acid, eicosapentaenoic acid, palmitoleic acid, and myristic acid.

Stimulation of apical sodium-dependent bile acid transporter expands the bile acid pool and generates bile acids with positive feedback properties.

Science.gov (United States)

Rudling, Mats; Bonde, Ylva

2015-01-01

Bile acid synthesis has been considered a prototype for how a physiological process is controlled by end product feedback inhibition. By this feedback inhibition, bile acid concentrations are kept within safe ranges. However, careful examination of published rodent data strongly suggests that bile acid synthesis is also under potent positive feedback control by hydrophilic bile acids. Current concepts on the regulation of bile acid synthesis are derived from mouse models. Recent data have shown that mice have farnesoid X receptor (FXR) antagonistic bile acids capable of quenching responses elicited by FXR agonistic bile acids. This is important to recognize to understand the regulation of bile acid synthesis in the mouse, and in particular to clarify if mouse model findings are valid also in the human situation. In addition to classic end product feedback inhibition, regulation of bile acid synthesis in the mouse largely appears also to be driven by changes in hepatic levels of murine bile acids such as α- and β-muricholic acids. This has not been previously recognized. Stimulated bile acid synthesis or induction of the apical sodium-dependent bile acid transporter in the intestine, increase the availability of chenodeoxycholic acid in the liver, thereby promoting hepatic conversion of this bile acid into muricholic acids. Recognition of these mechanisms is essential for understanding the regulation of bile acid synthesis in the mouse, and for our awareness of important species differences in the regulation of bile acid synthesis in mice and humans. 2015 S. Karger AG, Basel.

Increased Bile Acid Synthesis and Impaired Bile Acid Transport in Human Obesity

OpenAIRE

Haeusler, Rebecca A.; Camastra, Stefania; Nannipieri, Monica; Astiarraga, Brenno; Castro-Perez, Jose; Xie, Dan; Wang, Liangsu; Chakravarthy, Manu; Ferrannini, Ele

2015-01-01

We measured plasma bile acids, markers of bile acid synthesis, and expression of bile acid transporters in obese and nonobese subjects. We found that obesity was associated with increased bile acid synthesis and 12-hydroxylation, blunted response of plasma bile acids to insulin infusion or a mixed meal, and decreased expression of liver bile acid transporters.

21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and as...

Transformation of chenodeoxycholic acid to ursodeoxycholic acid in patients with Crohn's disease

International Nuclear Information System (INIS)

Miwa, H.; Yamamoto, M.; Nishida, T.; Yao, T.

1986-01-01

In vivo 7 beta-epimerization of chenodeoxycholic acid to ursodeoxycholic acid and the role of 7-ketolithocholic acid as an intermediate in this biotransformation were studied in 11 patients with Crohn's disease and in 5 healthy volunteers. The incorporation of deuterium into biliary ursodeoxycholic acid and 7-ketolithocholic acid was determined by computed gas chromatography-mass fragmentography after ingestion of a dideuterated chenodeoxycholic acid, chenodeoxycholic-11,12-d2 acid. The incorporation of deuterium into ursodeoxycholic acid increased to a peak level at 48 h in the patients with Crohn's disease, but was delayed in healthy volunteers. In 8 patients and 2 healthy controls there were small amounts of 7-ketolithocholic acid in bile. The incorporation of deuterium into 7-ketolithocholic acid was confirmed in only 2 patients and the peak level was noted at 48 h. These observations suggest that 7-ketolithocholic acid is an intermediate of this biotransformation in patients with Crohn's disease

Proximate composition, amino acid and fatty acid composition of fish maws.

Science.gov (United States)

Wen, Jing; Zeng, Ling; Xu, Youhou; Sun, Yulin; Chen, Ziming; Fan, Sigang

2016-01-01

Fish maws are commonly recommended and consumed in Asia over many centuries because it is believed to have some traditional medical properties. This study highlights and provides new information on the proximate composition, amino acid and fatty acid composition of fish maws of Cynoscion acoupa, Congresox talabonoides and Sciades proops. The results indicated that fish maws were excellent protein sources and low in fat content. The proteins in fish maws were rich in functional amino acids (FAAs) and the ratio of FAAs and total amino acids in fish maws ranged from 0.68 to 0.69. Among species, croaker C. acoupa contained the most polyunsaturated fatty acids, arachidonic acid, docosahexaenoic acid and eicosapntemacnioc acid, showing the lowest value of index of atherogenicity and index of thrombogenicity, showing the highest value of hypocholesterolemic/hypercholesterolemic ratio, which is the most desirable.

A Glutamic Acid-Producing Lactic Acid Bacteria Isolated from Malaysian Fermented Foods

Science.gov (United States)

Zareian, Mohsen; Ebrahimpour, Afshin; Bakar, Fatimah Abu; Mohamed, Abdul Karim Sabo; Forghani, Bita; Ab-Kadir, Mohd Safuan B.; Saari, Nazamid

2012-01-01

l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA) as a bioactive compound. PMID:22754309

Acetic acid extraction from aqueous solutions using fatty acids

NARCIS (Netherlands)

IJmker, H.M.; Gramblicka, M.; Kersten, Sascha R.A.; van der Ham, Aloysius G.J.; Schuur, Boelo

2014-01-01

A major challenge for production of acetic acid via bio-based routes is cost-effective concentration and purification of the acetic acid from the aqueous solutions, for which liquid–liquid extraction is a possible method. A main challenge in extraction of acetic acid from dilute aqueous solutions is

Nucleic acid-binding glycoproteins which solubilize nucleic acids in dilute acid: re-examination of the Ustilago maydis glycoproteins

Energy Technology Data Exchange (ETDEWEB)

Unrau, P.; Champ, D.R.; Young, J.L.; Grant, C.E.

1980-01-01

Holloman reported the isolation from Ustilago maydis of a glycoprotein which prevented the precipitation of nucleic acids in cold 5% trichloroacetic acid. Two glycoprotein fractions from U. maydis with this nucleic acid-solubilizing activity were isolated in our laboratory using improved purification procedures. The activity was not due to nuclease contamination. The glycoproteins are distinguished by: their ability to bind to concanavalin A-Sepharose; their differential binding to double- and single-stranded deoxyribonucleic acid, and to ribonucleic acid; their molecular weights (46,000 and 69,000); and the relative amounts present in growing versus nongrowing cells. Both fractions required sulfhydryl-reducing conditions for optimal yields, specific activity, and stability. Nucleic acid binding was cooperative, the minimum number of glycoproteins required to make a native T7 DNA molecule soluble in dilute acid being estimated at 2 and 15, respectively.

Docosahexaenoic acid affects arachidonic acid uptake in megakaryocytes

International Nuclear Information System (INIS)

Schick, P.K.; Webster, P.

1987-01-01

Dietary omega 3 fatty acids are thought to prevent atherosclerosis, possibly by modifying platelet (PT) function and arachidonic acid (20:4) metabolism. The study was designed to determine whether omega 3 fatty acids primarily affect 20:4 metabolism in megakaryocytes (MK), bone marrow precursors of PT, rather than in circulating PT. MK and PT were isolated from guinea pigs and incubated with [ 14 C]-20:4 (0.13uM). Docosahexaenoic acid (22:6) is a major omega 3 fatty acid in marine oils. The incubation of MK with 22:6 (0.1, 1.0 uM) resulted in the decrease of incorporation of [ 14 C]-20:4 into total MK phospholipids, 16% and 41% respectively. Alpha-linolenic acid (18:3), a major omega 3 fatty acid present in American diets, had no effect on 20:4 uptake in MK. 22:6 primarily affected the uptake of [ 14 C]-20:4 into phosphatidylethanolamine (PE) and phosphatidylserine (PS) in MK. In MK, 22:6 (0.1, 1.0 uM) caused a decrease of incorporation of [ 14 C]-20:4 into PE, 21% and 55% respectively; a decrease into PS, 16% and 48% respectively; but only a decrease of 4% and 18%, respectively, into phosphatidylcholine; and a decrease of 3% and 21% into phosphatidylinositol 22:6 (3.0 uM) had no effect on the uptake of AA into PT phospholipids. The study shows that 22:6 has a selective effect on AA uptake in MK and that the acylation or transacylation of PE and PS are primarily affected. 22:6 and other marine omega 3 fatty acids appear to primarily affect megakaryocytes which may result in the production of platelets with abnormal content and compartmentalization of AA

Transport of acidic amino acids by human jejunal brush-border membrane vesicles

International Nuclear Information System (INIS)

Rajendran, V.M.; Harig, J.M.; Adams, M.B.; Ramaswamy, K.

1987-01-01

This study characterizes the transport of radiolabeled acidic amino acids into brush-border membrane vesicles prepared from human jejunum. The uptakes of L-glutamic, L-aspartic, and D-aspartic acids were stimulated by a Na + gradient. Concentrative uptake (resulting in an overshoot phenomenon) of these dicarboxylic amino acids occurred when there was an outward K + gradient. In addition, increasing K + gradients resulted in enhanced uptake of L-glutamic acid. This K + requirement is somewhat specific as Rb + and Cs + could enhance uptake to a limited extent, whereas Li + and choline + showed no enhancement. The presence of a K + gradient did not affect the affinity of the carrier system for L-glutamic acid but it did increase the V/sub max/. The presence of extravesicular anions having differing membrane permeabilities did not altar L-glutamic acid uptake indicating an absence of an effect of membrane potential on the transport process. Finally, the human transport system for L-glutamic acid appears to be specific for acidic amino acids as demonstrated by inhibition studies. The studies demonstrate a transport system in human jejunum specific for acidic amino acids that is energized by an inward Na + gradient and an outward K + gradient

SYNTHESIS OF FLAVANONE-6-CARBOXYLIC ACID DERIVATIVES FROM SALICYLIC ACID DERIVATIVE

Directory of Open Access Journals (Sweden)

Muhammad Idham Darussalam Mardjan

2012-02-01

Full Text Available Synthesis of flavanone-6-carboxylic acid derivatives had been conducted via the route of chalcone. The synthesis was carried out from salicylic acid derivative, i.e. 4-hydroxybenzoic acid, via esterification, Fries rearrangement, Claisen-Schmidt condensation and 1,4-nucleophilic addition reactions. Structure elucidation of products was performed using FT-IR, 1H-NMR, GC-MS and UV-Vis spectrometers. Reaction of 4-hydroxybenzoic acid with methanol catalyzed with sulfuric acid produced methyl 4-hydroxybenzoate in 87% yield. The acid-catalyzed-acetylation of the product using acetic anhydride gave methyl 4-acetoxybenzoate in 75% yield. Furthermore, solvent-free Fries rearrangement of methyl 4-acetoxybenzoate in the presence of AlCl3 produced 3-acetyl-4-hydroxybenzoic acid as the acetophenone derivatives in 67% yield. Then, Claisen-Schmidt condensation of the acetophenone and benzaldehyde derivatives of p-anisaldehyde and veratraldehyde in basic condition gave 2'-hydroxychalcone-5'-carboxylic acid derivatives  in 81 and 71 % yield, respectively. Finally, the ring closure reaction of the chalcone yielded the corresponding flavanone-6-carboxylic acids in 67 and 59% yield, respectively.

A high dynamic range programmable CMOS front-end filter with a tuning range from 1850 to 2400 MHz

DEFF Research Database (Denmark)

Christensen, Kåre Tais; Lee, Thomas H.; Bruun, Erik

2005-01-01

This paper presents a highly programmable front-end filter and amplifier intended to replace SAW filters and low noise amplifiers (LNA) in multi-mode direct conversion radio receivers. The filter has a 42 MHz bandwidth, is tunable from 1850 to 2400 MHz, achieves a 5.8 dB NF, -25 dBm in-band 1-d...

Extraterrestrial material analysis: loss of amino acids during liquid-phase acid hydrolysis

Science.gov (United States)

Buch, Arnaud; Brault, Amaury; Szopa, Cyril; Freissinet, Caroline

2015-04-01

Searching for building blocks of life in extraterrestrial material is a way to learn more about how life could have appeared on Earth. With this aim, liquid-phase acid hydrolysis has been used, since at least 1970 , in order to extract amino acids and other organic molecules from extraterrestrial materials (e.g. meteorites, lunar fines) or Earth analogues (e.g. Atacama desert soil). This procedure involves drastic conditions such as heating samples in 6N HCl for 24 h, either under inert atmosphere/vacuum, or air. Analysis of the hydrolyzed part of the sample should give its total (free plus bound) amino acid content. The present work deals with the influence of the 6N HCl hydrolysis on amino acid degradation. Our experiments have been performed on a standard solution of 17 amino acids. After liquid-phase acid hydrolysis (6N HCl) under argon atmosphere (24 h at 100°C), the liquid phase was evaporated and the dry residue was derivatized with N-Methyl-N-(t-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) and dimethylformamide (DMF), followed by gas chromatography-mass spectrometry analysis. After comparison with derivatized amino acids from the standard solution, a significant reduction of the chromatographic peak areas was observed for most of the amino acids after liquid-phase acid hydrolysis. Furthermore, the same loss pattern was observed when the amino acids were exposed to cold 6N HCl for a short amount of time. The least affected amino acid, i.e. glycine, was found to be 73,93% percent less abundant compared to the non-hydrolyzed standard, while the most affected, i.e. histidine, was not found in the chromatograms after hydrolysis. Our experiments thereby indicate that liquid-phase acid hydrolysis, even under inert atmosphere, leads to a partial or total loss of all of the 17 amino acids present in the standard solution, and that a quick cold contact with 6N HCl is sufficient to lead to a loss of amino acids. Therefore, in the literature, the reported increase

Acidic Ionic Liquids.

Science.gov (United States)

Amarasekara, Ananda S

2016-05-25

Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

Emocionálna saturácia v kontexte arteterapie

OpenAIRE

MIHALOVIČOVÁ, Jaroslava

2012-01-01

Bachelor thesis presents a view of emotional saturation with the help of art therapy. The work presents the application of art therapy program, which is involving so called Roznovska art therapy, using connection with the fine art for the people in advanced old age. The aim is to feed the emotions of people in late old age through the art therapy program and provide joy and satisfaction of creating in the last moments of life.

Investigation of Ureaplasma urealyticum biovars and their relationship with antimicrobial resistance

Directory of Open Access Journals (Sweden)

Zhu Chang-tai

2011-01-01

Full Text Available Purpose: To develop Taqman fluorescence quantitative polymerase chain reaction (PCR method for investigating the characteristics of the distributions of Ureaplasma urealyticum (UU biovars and to explore the relationship between UU biovars and antimicrobial resistance. Materials and Methods: By the method of culture, Ureaplasma species were detected. Taqman fluorescence quantitative PCR for detecting UU biovars were developed and UU clinical isolates were detected to distinguish biovars. The broth micro-dilution susceptibility testing methods were used to determine UU susceptibility. Results: By Taqman PCR method, UU biovars was successfully detected. Of 126 samples, biovar 1 was found in 73 (57.94%. There was a statistical difference between genital-urinary tract infection group and asymptomatic group (P<0.05. In the region, UU biovar 1 to 9 kinds of agents kept higher susceptibility rates, but biovar 2 maintained higher susceptibility rates only to tetracyclines. Compared with biovar 1, UU biovar 2 resistance rates to 7 kinds of agents were higher (P<0.05. Conclusions: (1 Our new established Taqman PCR method is a useful tool for screening UU biovars. (2 UU biovar 1 predominated in asymptomatic population; whereas in genital-urinary tract infection population UU biovar 2 had a higher proportion. (3 The characteristics of drug resistance were different between UU biovars. Overall, both two biovars remained higher susceptibility rates to tetracyclines. A majority of biovor 1 strains were sensitive to macrolides and quinolones; while only a small number of biovar 2 strains kept sensitive to roxithromycin and quinolones, a large proportion of biovar 2 strains were found in intermediate ranges.

"JCE" Classroom Activity #109: My Acid Can Beat Up Your Acid!

Science.gov (United States)

Putti, Alice

2011-01-01

In this guided-inquiry activity, students investigate the ionization of strong and weak acids. Bead models are used to study acid ionization on a particulate level. Students analyze seven strong and weak acid models and make generalizations about the relationship between acid strength and dissociation. (Contains 1 table and 2 figures.)

Metabolic pathways regulated by abscisic acid, salicylic acid and γ-aminobutyric acid in association with improved drought tolerance in creeping bentgrass (Agrostis stolonifera).

Science.gov (United States)

Li, Zhou; Yu, Jingjin; Peng, Yan; Huang, Bingru

2017-01-01

Abscisic acid (ABA), salicylic acid (SA) and γ-aminobutyric acid (GABA) are known to play roles in regulating plant stress responses. This study was conducted to determine metabolites and associated pathways regulated by ABA, SA and GABA that could contribute to drought tolerance in creeping bentgrass (Agrostis stolonifera). Plants were foliar sprayed with ABA (5 μM), GABA (0.5 mM) and SA (10 μM) or water (untreated control) prior to 25 days drought stress in controlled growth chambers. Application of ABA, GABA or SA had similar positive effects on alleviating drought damages, as manifested by the maintenance of lower electrolyte leakage and greater relative water content in leaves of treated plants relative to the untreated control. Metabolic profiling showed that ABA, GABA and SA induced differential metabolic changes under drought stress. ABA mainly promoted the accumulation of organic acids associated with tricarboxylic acid cycle (aconitic acid, succinic acid, lactic acid and malic acid). SA strongly stimulated the accumulation of amino acids (proline, serine, threonine and alanine) and carbohydrates (glucose, mannose, fructose and cellobiose). GABA enhanced the accumulation of amino acids (GABA, glycine, valine, proline, 5-oxoproline, serine, threonine, aspartic acid and glutamic acid) and organic acids (malic acid, lactic acid, gluconic acid, malonic acid and ribonic acid). The enhanced drought tolerance could be mainly due to the enhanced respiration metabolism by ABA, amino acids and carbohydrates involved in osmotic adjustment (OA) and energy metabolism by SA, and amino acid metabolism related to OA and stress-defense secondary metabolism by GABA. © 2016 Scandinavian Plant Physiology Society.

Complexity in Acid-Base Titrations: Multimer Formation Between Phosphoric Acids and Imines.

Science.gov (United States)

Malm, Christian; Kim, Heejae; Wagner, Manfred; Hunger, Johannes

2017-08-10

Solutions of Brønsted acids with bases in aprotic solvents are not only common model systems to study the fundamentals of proton transfer pathways but are also highly relevant to Brønsted acid catalysis. Despite their importance the light nature of the proton makes characterization of acid-base aggregates challenging. Here, we track such acid-base interactions over a broad range of relative compositions between diphenyl phosphoric acid and the base quinaldine in dichloromethane, by using a combination of dielectric relaxation and NMR spectroscopy. In contrast to what one would expect for an acid-base titration, we find strong deviations from quantitative proton transfer from the acid to the base. Even for an excess of the base, multimers consisting of one base and at least two acid molecules are formed, in addition to the occurrence of proton transfer from the acid to the base and simultaneous formation of ion pairs. For equimolar mixtures such multimers constitute about one third of all intermolecular aggregates. Quantitative analysis of our results shows that the acid-base association constant is only around six times larger than that for the acid binding to an acid-base dimer, that is, to an already protonated base. Our findings have implications for the interpretation of previous studies of reactive intermediates in organocatalysis and provide a rationale for previously observed nonlinear effects in phosphoric acid catalysis. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Nocturnal weakly acidic reflux promotes aspiration of bile acids in lung transplant recipients.

Science.gov (United States)

Blondeau, Kathleen; Mertens, Veerle; Vanaudenaerde, Bart A; Verleden, Geert M; Van Raemdonck, Dirk E; Sifrim, Daniel; Dupont, Lieven J

2009-02-01

Gastroesophageal reflux (GER) and aspiration of bile acids have been implicated as non-alloimmune risk factors for the development of bronchiolitis obliterans syndrome (BOS) after lung transplantation. The aim of our study was to investigate the association between GER and gastric aspiration of bile acids and to establish which reflux characteristics may promote aspiration of bile acids into the lungs and may feature as a potential diagnostic tool in identifying lung transplantation (LTx) patients at risk for aspiration. Twenty-four stable LTx recipients were studied 1 year after transplantation. All patients underwent 24-hour ambulatory impedance-pH recording for the detection of acid (pH acidic (pH 4 to 7) reflux. On the same day, bronchoalveolar lavage fluid (BALF) was collected and then analyzed for the presence of bile acids (Bioquant enzymatic assay). Increased GER was detected in 13 patients, of whom 9 had increased acid reflux and 4 had exclusively increased weakly acidic reflux. Sixteen patients had detectable bile acids in the BALF (0.6 [0.4 to 1.5] micromol/liter). The 24-hour esophageal volume exposure was significantly increased in patients with bile acids compared to patients without bile acids in the BALF. Acid exposure and the number of reflux events (total, acid and weakly acidic) were unrelated to the presence of bile acids in the BALF. However, both nocturnal volume exposure and the number of nocturnal weakly acidic reflux events were significantly higher in patients with bile acids in the BALF. Weakly acidic reflux events, especially during the night, are associated with the aspiration of bile acids in LTx recipients and may therefore feature as a potential risk factor for the development of BOS.

Enzymatic synthesis of 11C-pyruvic acid and 11C-L-lactic acid

International Nuclear Information System (INIS)

Cohen, M.B.; Spolter, L.; Chang, C.C.; Cook, J.S.; Macdonald, N.S.

1980-01-01

L-Lactic acid is formed as the end product of glycolysis under anaerobic conditions in all cells, but this reaction is of special significance in the myocardium. L-Lactic acid is reversibly formed from and is in equilibrium with myocardial pyruvic acid, which is its sole metabolic pathway. 11 C-Pyruvic acid is synthesized from 11 C carbon dioxide using pyruvate-ferredoxin oxidoreductase and coenzymes. The 11 C-pyruvic acid is then converted to 11 -L-lactic acid by lactic acid dehydrogenase. The availability of 11 C-pyruvic acid and 11 C-L-lactic acid will permit the in vivo investigation of lactate metabolism. (author)

Acid rain. Les pluies acides

Energy Technology Data Exchange (ETDEWEB)

Curren, T

1979-11-28

This report was produced for the use of Members of Parliament and House of Commons committees. The document describes the formation of acid rain, emissions of acidifying pollutants in North America, the growth of the problem and its environmental effects on aquatic and terrestrial ecosystems, human health and man-made structures. Areas of Canada which are most susceptible are identified. Actions taken by Parliament are given, including the formation of a sub-committee on acid rain and the passing of Bill C-51 in 1980 to amend the Clean Air Act, bringing it closer to a similar law in the U.S. A chronology of government responses to acid rain at the international, national and provincial level, is given. The most recent government actions included the passing of the US Clean Air Act by the Senate, the amending of the act into law, and commencement of negotiations to develop a Canada-US Air Quality Accord. 10 refs.

Incorporation of Oxygen into Abscisic Acid and Phaseic Acid from Molecular Oxygen 1

Science.gov (United States)

Creelman, Robert A.; Zeevaart, Jan A. D.

1984-01-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% 18O2 and 80% N2 indicates that one atom of 18O is incorporated in the 6′-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase. Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing 18O2 indicates that one atom of 18O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1′-, 4′-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1′- and 4′-positions of abscisic acid which is converted to abscisic acid under conditions of water stress. PMID:16663564

Synthesis and biological activity of amino acid conjugates of abscisic acid.

Science.gov (United States)

Todoroki, Yasushi; Narita, Kenta; Muramatsu, Taku; Shimomura, Hajime; Ohnishi, Toshiyuki; Mizutani, Masaharu; Ueno, Kotomi; Hirai, Nobuhiro

2011-03-01

We prepared 19 amino acid conjugates of the plant hormone abscisic acid (ABA) and investigated their biological activity, enzymatic hydrolysis by a recombinant Arabidopsis amidohydrolases GST-ILR1 and GST-IAR3, and metabolic fate in rice seedlings. Different sets of ABA-amino acids induced ABA-like responses in different plants. Some ABA-amino acids, including some that were active in bioassays, were hydrolyzed by recombinant Arabidopsis GST-IAR3, although GST-ILR1 did not show hydrolysis activity for any of the ABA-amino acids. ABA-L-Ala, which was active in all the bioassays, an Arabidopsis seed germination, spinach seed germination, and rice seedling elongation assays, except in a lettuce seed germination assay and was hydrolyzed by GST-IAR3, was hydrolyzed to free ABA in rice seedlings. These findings suggest that some plant amidohydrolases hydrolyze some ABA-amino acid conjugates. Because our study indicates the possibility that different plants have hydrolyzing activity toward different ABA-amino acids, an ABA-amino acid may function as a species-selective pro-hormone of ABA. Copyright © 2011 Elsevier Ltd. All rights reserved.

10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

Energy Technology Data Exchange (ETDEWEB)

Goto, Tsuyoshi, E-mail: tgoto@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Kim, Young-Il; Furuzono, Tomoya [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Takahashi, Nobuyuki [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Ohue, Ryuji [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University (Japan); Nomura, Wataru [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji 611-0011 (Japan); Sugawara, Tatsuya [Laboratory of Marine Bioproducts Technology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502 (Japan); Yu, Rina [Department of Food Science and Nutrition, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Kitamura, Nahoko [Laboratory of Fermentation Physiology and Applied Microbiology, Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502 (Japan); and others

2015-04-17

Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis.

10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

International Nuclear Information System (INIS)

Goto, Tsuyoshi; Kim, Young-Il; Furuzono, Tomoya; Takahashi, Nobuyuki; Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia; Ohue, Ryuji; Nomura, Wataru; Sugawara, Tatsuya; Yu, Rina; Kitamura, Nahoko

2015-01-01

Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis

Smallpox and pan-orthopox virus detection by real-time 3'-minor groove binder TaqMan assays on the roche LightCycler and the Cepheid smart Cycler platforms.

Science.gov (United States)

Kulesh, David A; Baker, Robert O; Loveless, Bonnie M; Norwood, David; Zwiers, Susan H; Mucker, Eric; Hartmann, Chris; Herrera, Rafael; Miller, David; Christensen, Deanna; Wasieloski, Leonard P; Huggins, John; Jahrling, Peter B

2004-02-01

We designed, optimized, and extensively tested several sensitive and specific real-time PCR assays for rapid detection of both smallpox and pan-orthopox virus DNAs. The assays are based on TaqMan 3'-minor groove binder chemistry and were performed on both the rapid-cycling Roche LightCycler and the Cepheid Smart Cycler platforms. The hemagglutinin (HA) J7R, B9R, and B10R genes were used as targets for the variola virus-specific assays, and the HA and DNA polymerase-E9L genes were used as targets for the pan-orthopox virus assays. The five orthopox virus assays were tested against a panel of orthopox virus DNAs (both genomic and cloned) at the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID). The results indicated that each assay was capable of detecting both the appropriate cloned gene and genomic DNA. The assays showed no cross-reactivity to the 78 DNAs in the USAMRIID bacterial cross-reactivity panel. The limit of detection (LOD) of each assay was determined to be between 12 and 25 copies of target DNA. The assays were also run against a blind panel of DNAs at the Centers for Disease Control and Prevention (CDC) on both the LightCycler and the Smart Cycler. The panel consisted of eight different variola virus isolates, five non-variola virus orthopox virus isolates, two varicella-zoster virus isolates, and one herpes simplex virus isolate. Each sample was tested in triplicate at 2.5 ng, 25 pg, 250 fg, and 2.5 fg, which represent 1.24 x 10(7), 1.24 x 10(5), 1.24 x 10(3), and 1.24 x 10(1) genome equivalents, respectively. The results indicated that each of the five assays was 100% specific (no false positives) when tested against both the USAMRIID panels and the CDC blind panel. With the CDC blind panel, the LightCycler was capable of detecting 96.2% of the orthopox virus DNAs and 93.8% of the variola virus DNAs. The Smart Cycler was capable of detecting 92.3% of the orthopox virus DNAs and between 75 and 93.8% of the variola virus DNAs

Uptake of actinides by sulphonated phosphinic acid resin from acid medium

International Nuclear Information System (INIS)

Jaya Mohandas; Srinivasa Rao, V.; Vijayakumar, N.; Kumar, T.; Velmurugan, S.; Narasimhan, S.V.

2014-01-01

The removal of uranium and americium from nitric acid solutions by sulphonated phosphinic acid resin has been investigated. The capacity of the sulphonated resin exceeds the capacities of phosphinic acid resin and commercial cation exchange resin. Other advantages of the sulphonated resin for uranium and americium removal include reduced sensitivity to acidity and inert salt concentration. (author)

Unsaturated fatty acids protect trophoblast cells from saturated fatty acid-induced autophagy defects.

Science.gov (United States)

Hong, Ye-Ji; Ahn, Hyo-Ju; Shin, Jongdae; Lee, Joon H; Kim, Jin-Hoi; Park, Hwan-Woo; Lee, Sung Ki

2018-02-01

Dysregulated serum fatty acids are associated with a lipotoxic placental environment, which contributes to increased pregnancy complications via altered trophoblast invasion. However, the role of saturated and unsaturated fatty acids in trophoblastic autophagy has yet to be explored. Here, we demonstrated that prolonged exposure of saturated fatty acids interferes with the invasiveness of human extravillous trophoblasts. Saturated fatty acids (but not unsaturated fatty acids) inhibited the fusion of autophagosomes and lysosomes, resulting in the formation of intracellular protein aggregates. Furthermore, when the trophoblast cells were exposed to saturated fatty acids, unsaturated fatty acids counteracted the effects of saturated fatty acids by increasing degradation of autophagic vacuoles. Saturated fatty acids reduced the levels of the matrix metalloproteinases (MMP)-2 and MMP-9, while unsaturated fatty acids maintained their levels. In conclusion, saturated fatty acids induced decreased trophoblast invasion, of which autophagy dysfunction plays a major role. Copyright © 2017 Elsevier B.V. All rights reserved.

Formation of organic acids from trace carbon in acidic oxidizing media

International Nuclear Information System (INIS)

Terrassier, C.

2003-01-01

Carbon 14 does not fully desorb as CO 2 during the hot concentrated nitric acid dissolution step of spent nuclear fuel reprocessing: a fraction is entrained in solution into the subsequent process steps as organic species. The work described in this dissertation was undertaken to identify the compounds arising from the dissolution in 3 N nitric acid of uranium carbides (selected as models of the chemical form of carbon 14 in spent fuel) and to understand their formation and dissolution mechanism. The compounds were present at traces in solution, and liquid-solid extraction on a specific stationary phase (porous graphite carbon) was selected to concentrate the monoaromatic poly-carboxylic acids including mellitic acid, which is mentioned in the literature but has not been formally identified. The retention of these species and of oxalic acid - also cited in the literature - was studied on this stationary phase as a function of the mobile phase pH, revealing an ion exchange retention mechanism similar to the one observed for benzyltrimethylammonium polystyrene resins. The desorption step was then optimized by varying the eluent pH and ionic strength. Mass spectrometry analysis of the extracts identified acetic acid, confirmed the presence of mellitic acid, and revealed compounds of high molecular weight (about 200 g/mol); the presence of oxalic acid was confirmed by combining gas chromatography and mass spectrometry. Investigating the dissolution of uranium and zirconium carbides in nitric acid provided considerable data on the reaction and suggested a reaction mechanism. The reaction is self-catalyzing via nitrous acid, and the reaction rate de pends on the acidity and nitrate ion concentration in solution. Two uranium carbide dissolution mechanisms are proposed: one involves uranium at oxidation state +IV in solution, coloring the dissolution solution dark green, and the other assumes that uranium monocarbide is converted to uranium oxide. The carboxylic acid

Synthesis of bio-based methacrylic acid by decarboxylation of itaconic acid and citric acid catalyzed by solid transition-metal catalysts.

Science.gov (United States)

Le Nôtre, Jérôme; Witte-van Dijk, Susan C M; van Haveren, Jacco; Scott, Elinor L; Sanders, Johan P M

2014-09-01

Methacrylic acid, an important monomer for the plastics industry, was obtained in high selectivity (up to 84%) by the decarboxylation of itaconic acid using heterogeneous catalysts based on Pd, Pt and Ru. The reaction takes place in water at 200-250 °C without any external added pressure, conditions significantly milder than those described previously for the same conversion with better yield and selectivity. A comprehensive study of the reaction parameters has been performed, and the isolation of methacrylic acid was achieved in 50% yield. The decarboxylation procedure is also applicable to citric acid, a more widely available bio-based feedstock, and leads to the production of methacrylic acid in one pot in 41% selectivity. Aconitic acid, the intermediate compound in the pathway from citric acid to itaconic acid was also used successfully as a substrate. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Role of nitrous acid during the dissolution of UO2 in nitric acid

International Nuclear Information System (INIS)

Deigan, N.; Pandey, N.K.; Kamachi Mudali, U.; Joshi, J.B.

2016-01-01

Understanding the dissolution behaviour of sintered UO 2 pellet in nitric acid is very important in designing an industrial scale dissolution system for the plutonium rich fast reactor MOX fuel. In the current article we have established the role of nitrous acid on the dissolution kinetics of UO 2 pellets in nitric acid. Under the chemical conditions that prevail in a typical Purex process, NO and NO 2 gases gets generated in the process streams. These gases produce nitrous acid in nitric acid medium. In addition, during the dissolution of UO 2 in nitric acid medium, nitrous acid is further produced in-situ at the pellet solution interface. As uranium dissolves oxidatively in nitric acid medium wherein it goes from U(IV) in solid to U(VI) in liquid, presence of nitrous acid (a good oxidizing agent) accelerates the reaction rate. Hence for determining the reaction mechanism of UO 2 dissolution in nitric acid medium, knowing the nitrous acid concentration profile during the course of dissolution is important. The current work involves the measurement of nitrous acid concentration during the course of dissolution of sintered UO 2 pellets in 8M starting nitric acid concentration as a function of mixing intensity from unstirred condition to 1500 RPM

Research and performance evaluation on an HA integrated acid system for sandstone acidizing

Directory of Open Access Journals (Sweden)

Liqiang Zhao

2018-03-01

Full Text Available When the conventional sandstone acidizing technologies are adopted, many slugs are needed in the injection of prepad fluid, treatment fluid and postpad fluid, and consequently the production and operation suffers inconveniences and difficulties. In view of this, a kind of HA integrated acid system which is mainly composed of organic polybasic acids (HA+HCl + HF and an efficient organic solvent was developed in this paper based on the idea of integrated acid replacing ''multiple steps'' and high efficiency and intensification. Via this HA integrated acid system, the complicated blockage in sandstone reservoirs can be removed effectively. Then, experiments were carried out on this system to evaluate its performance in terms of its retardance, organic blockage dissolution, chelating and precipitation inhibition. It is indicated that this new system can not only realize the acidizing of conventional integrated acid, but also present a good retarding performance by controlling H+ multi-stage ionization step by step and by forming silica acid-aluminum phosphonate film on the surface of clay minerals; that via this new HA integrated acid system, the organic blockage can be removed efficiently; and that it is wider in pH solution range than conventional APCs (aminopolycarboxyliates chelants, stronger in chelating capacity of Ca2+, Mg2+ and Fe3+ than conventional chelants (e.g. EDTA, NTA and DTPA, and better in precipitation inhibition on metal fluoride, fluosilicic acid alkali metal, fluoaluminic acid alkali metal and hydroxide than multi-hydrogen acid, fluoboric acid and mud acid systems. These research results provide a technical support for the plugging removal in high-temperature deep oil and gas reservoirs. Keywords: Organic polybasic acid, Integrated acid, Retardance, Chelating, Precipitation, Acidizing, Sandstone, Reservoir

Bile acid sequestrants

DEFF Research Database (Denmark)

Hansen, Morten; Sonne, David P; Knop, Filip K

2014-01-01

Bile acids are synthesized in the liver from cholesterol and have traditionally been recognized for their role in absorption of lipids and in cholesterol homeostasis. In recent years, however, bile acids have emerged as metabolic signaling molecules that are involved in the regulation of lipid...... and glucose metabolism, and possibly energy homeostasis, through activation of the bile acid receptors farnesoid X receptor (FXR) and TGR5. Bile acid sequestrants (BASs) constitute a class of drugs that bind bile acids in the intestine to form a nonabsorbable complex resulting in interruption...... of the enterohepatic circulation. This increases bile acid synthesis and consequently reduces serum low-density lipoprotein cholesterol. Also, BASs improve glycemic control in patients with type 2 diabetes. Despite a growing understanding of the impact of BASs on glucose metabolism, the mechanisms behind their glucose...

Reaction Kinetics of Monomethylhydrazine With Nitrous Acid in Perchloric Acid Solution

International Nuclear Information System (INIS)

Wei Yan; Wang Hui; Pan Yongjun; Cong Haifeng; Jiao Haiyang; Jia Yongfen; Zheng Weifang

2009-01-01

The oxidation of monomethylhydrazine (MMH) by nitrous acid was researched in perchloric acid solution with spectrophotometry. The rate equation has been determined as follows: -dc (HNO 2 ) /dt= kc (H + ) 0.9 c (MMH) 1.1 c (HNO 2 ), k is (46.0 ± 2.7) L 2 / (mol 2 · s) with the initial perchlorate concentration of 0.50 mol/L at the temperature of 4.5 degree C. The corresponding activation energy of the reaction is (42.4 ± 0.1) kJ/mol. The results indicate that oxidation of mono-methylhydrazine (MMH) by nitrous acid is fast. The higher concentration of MMH can accelerate the reduction process of nitrous acid. Higher acidity can also speed up the reduction of nitrous acid. (authors)

Bile acids: regulation of apoptosis by ursodeoxycholic acid.

Science.gov (United States)

Amaral, Joana D; Viana, Ricardo J S; Ramalho, Rita M; Steer, Clifford J; Rodrigues, Cecília M P

2009-09-01

Bile acids are a group of molecular species of acidic steroids with peculiar physical-chemical and biological characteristics. At high concentrations they become toxic to mammalian cells, and their presence is pertinent in the pathogenesis of several liver diseases and colon cancer. Bile acid cytoxicity has been related to membrane damage, but also to nondetergent effects, such as oxidative stress and apoptosis. Strikingly, hydrophilic ursodeoxycholic acid (UDCA), and its taurine-conjugated form (TUDCA), show profound cytoprotective properties. Indeed, these molecules have been described as potent inhibitors of classic pathways of apoptosis, although their precise mode of action remains to be clarified. UDCA, originally used for cholesterol gallstone dissolution, is currently considered the first choice therapy for several forms of cholestatic syndromes. However, the beneficial effects of both UDCA and TUDCA have been tested in other experimental pathological conditions with deregulated levels of apoptosis, including neurological disorders, such as Alzheimer's, Parkinson's, and Huntington's diseases. Here, we review the role of bile acids in modulating the apoptosis process, emphasizing the anti-apoptotic effects of UDCA and TUDCA, as well as their potential use as novel and alternate therapeutic agents for the treatment of apoptosis-related diseases.

Phytanic acid-an overlooked bioactive fatty acid in dairy fat?

DEFF Research Database (Denmark)

Hellgren, Lars

2010-01-01

dissipation in skeletal muscles. Phytanic acid levels in serum are associated with an increased risk of developing prostate cancer, but the available data do not support a general causal link between circulating phytanic acid and prostate cancer risk. However, certain individuals, with specific single......Phytanic acid is a multibranched fatty acid with reported retinoid X receptor (RXR) and peroxisome proliferator-activated receptor-alpha (PPAR-alpha) agonist activity, which have been suggested to have preventive effects on metabolic dysfunctions. Serum level in man is strongly correlated...

The Polyunsaturated Fatty Acids Arachidonic Acid and Docosahexaenoic Acid Induce Mouse Dendritic Cells Maturation but Reduce T-Cell Responses In Vitro

Science.gov (United States)

Carlsson, Johan A.; Wold, Agnes E.; Sandberg, Ann-Sofie; Östman, Sofia M.

2015-01-01

Long-chain polyunsaturated fatty acids (PUFAs) might regulate T-cell activation and lineage commitment. Here, we measured the effects of omega-3 (n-3), n-6 and n-9 fatty acids on the interaction between dendritic cells (DCs) and naïve T cells. Spleen DCs from BALB/c mice were cultured in vitro with ovalbumin (OVA) with 50 μM fatty acids; α-linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), linoleic acid or oleic acid and thereafter OVA-specific DO11.10 T cells were added to the cultures. Fatty acids were taken up by the DCs, as shown by gas chromatography analysis. After culture with arachidonic acid or DHA CD11c+ CD11b+ and CD11c+ CD11bneg DCs expressed more CD40, CD80, CD83, CD86 and PDL-1, while IAd remained unchanged. However, fewer T cells co-cultured with these DCs proliferated (CellTrace Violetlow) and expressed CD69 or CD25, while more were necrotic (7AAD+). We noted an increased proportion of T cells with a regulatory T cell (Treg) phenotype, i.e., when gating on CD4+ FoxP3+ CTLA-4+, CD4+ FoxP3+ Helios+ or CD4+ FoxP3+ PD-1+, in co-cultures with arachidonic acid- or DHA-primed DCs relative to control cultures. The proportion of putative Tregs was inversely correlated to T-cell proliferation, indicating a suppressive function of these cells. With arachidonic acid DCs produced higher levels of prostaglandin E2 while T cells produced lower amounts of IL-10 and IFNγ. In conclusion arachidonic acid and DHA induced up-regulation of activation markers on DCs. However arachidonic acid- and DHA-primed DCs reduced T-cell proliferation and increased the proportion of T cells expressing FoxP3, indicating that these fatty acids can promote induction of regulatory T cells. PMID:26619195

Plasma amino acids

Science.gov (United States)

Amino acids blood test ... types of methods used to determine the individual amino acid levels in the blood. ... test is done to measure the level of amino acids in the blood. An increased level of a ...

Oxidative cleavage of erucic acid for the synthesis of brassylic acid

Energy Technology Data Exchange (ETDEWEB)

Mohammed J. Nasrullah; Pooja Thapliyal; Erica N. Pfarr; Nicholas S. Dusek; Kristofer L. Schiele; James A. Bahr

2010-10-29

The main focus of this work is to synthesize Brassylic Acid (BA) using oxidative cleavage of Erucic Acid (EA). Crambe (Crambe abyssinica) is an industrial oilseed grown in North Dakota. Crambe has potential as an industrial fatty acid feedstock as a source of Erucic acid (EA). It has approximately 50-60 % of EA, a C{sub 22} monounsaturated fatty acid. Oxidative cleavage of unsaturated fatty acids derived from oilseeds produces long chain (9, 11, and 13 carbon atoms) dibasic and monobasic acids. These acids are known commercial feedstocks for the preparation of nylons, polyesters, waxes, surfactants, and perfumes. Other sources of EA are Rapeseed seed oil which 50-60 % of EA. Rapeseed is grown outside USA. The oxidative cleavage of EA was done using a high throughput parallel pressure reactor system. Kinetics of the reaction shows that BA yields reach a saturation at 12 hours. H{sub 2}WO{sub 4} was found to be the best catalyst for the oxidative cleavage of EA. High yields of BA were obtained at 80 C with bubbling of O{sub 2} or 10 bar of O{sub 2} for 12 hours.

Overview on mechanisms of acetic acid resistance in acetic acid bacteria.

Science.gov (United States)

Wang, Bin; Shao, Yanchun; Chen, Fusheng

2015-02-01

Acetic acid bacteria (AAB) are a group of gram-negative or gram-variable bacteria which possess an obligate aerobic property with oxygen as the terminal electron acceptor, meanwhile transform ethanol and sugar to corresponding aldehydes, ketones and organic acids. Since the first genus Acetobacter of AAB was established in 1898, 16 AAB genera have been recorded so far. As the main producer of a world-wide condiment, vinegar, AAB have evolved an elegant adaptive system that enables them to survive and produce a high concentration of acetic acid. Some researches and reviews focused on mechanisms of acid resistance in enteric bacteria and made the mechanisms thoroughly understood, while a few investigations did in AAB. As the related technologies with proteome, transcriptome and genome were rapidly developed and applied to AAB research, some plausible mechanisms conferring acetic acid resistance in some AAB strains have been published. In this review, the related mechanisms of AAB against acetic acid with acetic acid assimilation, transportation systems, cell morphology and membrane compositions, adaptation response, and fermentation conditions will be described. Finally, a framework for future research for anti-acid AAB will be provided.

Glutamic acid and folic acid production in aerobic and anaerobic probiotics

Directory of Open Access Journals (Sweden)

Zohre Taghi Abadi

2018-03-01

Full Text Available Introduction:From an industrial application or commercial point of view, glutamic acid is one of the most important amino acids and its microbial production has been reported from some bacteria. Regarding the role of probiotics to modulate human health and the ever-increasing demand of prebiotics in the food industry, in the current study, production of glutamic acid and folic acid from three probiotic bacteria (Bifidobacterium, Bifidobacterium bifidum, Sporolactobacillus was evaluated for the first time. Materials and methods: MRS broth and exclusive media was used for probiotic culture. The glutamic acid was identified using thin-layer chromatography and folic acid production was measured by folate kit. Each bacterium in terms of quality and quantity were measured by high pressure liquid chromatography. Results: Production of glutamic acid confirmed is based on the thin layer chromatography analysis and high pressure liquid chromatography results. In addition, it was observed that all three probiotics produce folic acid. The prevalence of folate in Bifidobacterium was measured as 315 mg/ml that was more than two other bacteria. Discussion and conclusion: To the best of our knowledge, this is the first report of microbial production of glutamic acid and folate from the probiotic bacteria. These beneficial bacteria can be used as a good source for mass production of these valuable compounds.

Folic acid and pantothenic acid protection against valproic acid-induced neural tube defects in CD-1 mice

Energy Technology Data Exchange (ETDEWEB)

Dawson, Jennifer E [Department of Pharmacology and Toxicology and School of Environmental Studies, Queen' s University, Kingston, Ontario, K7L 3N6 (Canada); Raymond, Angela M [Department of Pharmacology and Toxicology and School of Environmental Studies, Queen' s University, Kingston, Ontario, K7L 3N6 (Canada); Winn, Louise M [Department of Pharmacology and Toxicology and School of Environmental Studies, Queen' s University, Kingston, Ontario, K7L 3N6 (Canada)

2006-03-01

In utero exposure to valproic acid (VPA) during pregnancy is associated with an increased risk of neural tube defects (NTDs). Although the mechanism by which VPA mediates these effects is unknown, VPA-initiated changes in embryonic protein levels have been implicated. The objectives of this study were to investigate the effect of in utero VPA exposure on embryonic protein levels of p53, NF-{kappa}B, Pim-1, c-Myb, Bax, and Bcl-2 in the CD-1 mouse. We also evaluated the protective effects of folic acid and pantothenic acid on VPA-induced NTDs and VPA-induced embryonic protein changes in this model. Pregnant CD-1 mice were administered a teratogenic dose of VPA prior to neural tube closure and embryonic protein levels were analyzed. In our study, VPA (400 mg/kg)-induced NTDs (24%) and VPA-exposed embryos with an NTD showed a 2-fold increase in p53, and 4-fold decreases in NF-{kappa}B, Pim-1, and c-Myb protein levels compared to their phenotypically normal littermates (P < 0.05). Additionally, VPA increased the ratio of embryonic Bax/Bcl-2 protein levels (P < 0.05). Pretreatment of pregnant dams with either folic acid or pantothenic acid prior to VPA significantly protected against VPA-induced NTDs (P < 0.05). Folic acid also reduced VPA-induced alterations in p53, NF-{kappa}B, Pim-1, c-Myb, and Bax/Bcl-2 protein levels, while pantothenic acid prevented VPA-induced alterations in NF-{kappa}B, Pim-1, and c-Myb. We hypothesize that folic acid and pantothenic acid protect CD-1 embryos from VPA-induced NTDs by independent, but not mutually exclusive mechanisms, both of which may be mediated by the prevention of VPA-induced alterations in proteins involved in neurulation.

Uric acid - urine

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/003616.htm Uric acid urine test To use the sharing features on ... are no risks with this test. Images Uric acid test Uric acid crystals References Burns CM, Wortmann RL. Clinical ...

Cytotoxic effect of betulinic acid and betulinic acid acetate isolated ...

African Journals Online (AJOL)

Cytotoxic effect of betulinic acid and betulinic acid acetate isolated from Melaleuca cajuput on human myeloid leukemia (HL-60) cell line. ... The cytotoxic effect of betulinic acid (BA), isolated from Melaleuca cajuput a Malaysian plant and its four synthetic derivatives were tested for their cytotoxicity in various cell line or ...

Production of γ-linolenic acid and stearidonic acid by Synechococcus sp. PCC7002 containing cyanobacterial fatty acid desaturase genes

Science.gov (United States)

Dong, Xuewei; He, Qingfang; Peng, Zhenying; Yu, Jinhui; Bian, Fei; Li, Youzhi; Bi, Yuping

2016-07-01

Genetic modification is useful for improving the nutritional qualities of cyanobacteria. To increase the total unsaturated fatty acid content, along with the ratio of ω-3/ω-6 fatty acids, genetic engineering can be used to modify fatty acid metabolism. Synechococcus sp. PCC7002, a fast-growing cyanobacterium, does not contain a Δ6 desaturase gene and is therefore unable to synthesize γ-linolenic acid (GLA) and stearidonic acid (SDA), which are important in human health. In this work, we constructed recombinant vectors Syd6D, Syd15D and Syd6Dd15D to express the Δ15 desaturase and Δ6 desaturase genes from Synechocystis PCC6803 in Synechococcus sp. PCC7002, with the aim of expressing polyunsaturated fatty acids. Overexpression of the Δ15 desaturase gene in Synechococcus resulted in 5.4 times greater accumulation of α-linolenic acid compared with the wild-type while Δ6 desaturase gene expression produced both GLA and SDA. Co-expression of the two genes resulted in low-level accumulation of GLA but much larger amounts of SDA, accounting for as much to 11.64% of the total fatty acid content.

Kinetic study on the acid-catalyzed hydrolysis of cellulose to levulinic acid

NARCIS (Netherlands)

Girisuta, B.; Janssen, L. P. B. M.; Heeres, H. J.

2007-01-01

A variety of interesting bulk chemicals is accessible by the acid-catalyzed hydrolysis of cellulose. An interesting example is levulinic acid, a versatile precursor for fuel additives, polymers, and resins. A detailed kinetic study on the acid-catalyzed hydrolysis of cellulose to levulinic acid is

Utilization of acidic α-amino acids as acyl donors: an effective stereo-controllable synthesis of aryl-keto α-amino acids and their derivatives.

Science.gov (United States)

Wang, Lei; Murai, Yuta; Yoshida, Takuma; Okamoto, Masashi; Tachrim, Zetryana Puteri; Hashidoko, Yasuyuki; Hashimoto, Makoto

2014-05-16

Aryl-keto-containing α-amino acids are of great importance in organic chemistry and biochemistry. They are valuable intermediates for the construction of hydroxyl α-amino acids, nonproteinogenic α-amino acids, as well as other biofunctional components. Friedel-Crafts acylation is an effective method to prepare aryl-keto derivatives. In this review, we summarize the preparation of aryl-keto containing α-amino acids by Friedel-Crafts acylation using acidic α-amino acids as acyl-donors and Lewis acids or Brönsted acids as catalysts.