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Sample records for gpt delta transgenic

  1. Mutagenic Effects of Perfluorooctanesulfonic Acid in gpt Delta Transgenic System Are Mediated by Hydrogen Peroxide.

    PubMed

    Wang, Yichen; Zhang, Xuefeng; Wang, Meimei; Cao, Yiyi; Wang, Xinan; Liu, Yun; Wang, Juan; Wang, Jing; Wu, Lijun; Hei, Tom K; Luan, Yang; Xu, An

    2015-05-19

    Perfluorooctane sulfate (PFOS), a persistent organic pollutant, has recently been closely linked with an increased risk of tumorigenesis. However, PFOS has yielded negative results in various tests of genotoxicity. The present study aimed to investigate the mutagenic response to PFOS in the gpt delta transgenic mouse mutation system and to illustrate the contribution of hydrogen peroxide (H2O2) to PFOS genotoxicity. Mutations at the redBA/gam loci were determined by Spi(-) assay both in vitro and in vivo. DNA damage was measured by phosphorylated histone H2AX (γ-H2AX) and mouse bone marrow micronucleus (MN) testing. Our data showed that PFOS induced concentration-dependent increases in γ-H2AX foci and in mutation frequencies at redBA/gam loci in transgenic mouse embryonic fibroblast cells, which were confirmed by the formation of MNs in the bone marrow and the observations of mutation induction in the livers of gpt delta transgenic mice. Concurrent treatment with catalase, an efficient H2O2 scavenger, significantly decreased the formation of γ-H2AX foci and the mutation yields induced by PFOS. In addition, the generation of H2O2 was found to be closely related to the abnormal peroxisomal β-oxidation caused by PFOS. These finding might provide new mechanistical information about genotoxic effects of PFOS. PMID:25875360

  2. Potent genotoxicity of aminophenylnorharman, formed from non-mutagenic norharman and aniline, in the liver of gpt delta transgenic mouse.

    PubMed

    Masumura, Ken-ichi; Totsuka, Yukari; Wakabayashi, Keiji; Nohmi, Takehiko

    2003-12-01

    Aminophenylnorharman (APNH) is formed from non-mutagenic norharman and aniline, and is mutagenic to Salmonella typhimurium TA98 with S9 mix. Norharman and aniline are present in cigarette smoke and cooked foods and both compounds are detected in human urine samples, suggesting that APNH could be a mutagenic and carcinogenic human risk factor. The purpose of the present study was to determine the in vivo mutagenicity of APNH. Male gpt delta transgenic mice were fed a diet containing 10 or 20 p.p.m. APNH for 12 weeks. The gpt mutant frequency (MF) in the liver increased 10-fold in 20 p.p.m. APNH-treated mice, which was almost equivalent to the MF observed in the liver of the same transgenic mice treated with 300 p.p.m. 2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline for 12 weeks. In the colon mucosa, the gpt MF increased approximately 5-fold in 20 p.p.m. APNH-treated mice. Our results suggest that APNH is a strong hepatic mutagen in mice. The APNH-induced gpt mutations in the liver were dominated by G:C to T:A transversions, followed by G:C to A:T transitions. They also included single G:C deletions in G:C run sequences and 2 bp deletions: GCGC to GC and CGCG to CG. The Spi- deletion MF in the liver was 13-fold higher in 20 p.p.m. APNH-treated mice, relative to the control, and were dominated by single base pair deletions, in particular, in G:C run sequences. Large deletions were rare. The mutational characteristics induced by APNH are compared with those induced by other heterocyclic amines, and the human risk of APNH is discussed. PMID:12970073

  3. Genotoxicity assessment of intravenously injected titanium dioxide nanoparticles in gpt delta transgenic mice.

    PubMed

    Suzuki, Tetsuya; Miura, Nobuhiko; Hojo, Rieko; Yanagiba, Yukie; Suda, Megumi; Hasegawa, Tatsuya; Miyagawa, Muneyuki; Wang, Rui-Sheng

    2016-05-01

    Titanium dioxide (TiO2) nanoparticles are increasingly manufactured in large amounts for use in industrial applications such as cosmetics, pigments, foods, and as photo-catalysts. Many in vitro studies have examined the genotoxicity of TiO2 nanomaterials; some of these studies suggest that TiO2 nanoparticles (NPs) are genotoxic. Several in vivo studies have also been reported recently, but the results are inconsistent. In this study, we investigated, using several genotoxicity endpoints, the effects of dispersed TiO2 suspensions following multiple intravenous injections in mice. Male gpt Delta C57BL/6J mice were administered TiO2 NPs at doses of 2, 10 or 50mg/kg body weight per week for 4 consecutive weeks. Genotoxic effects were then analyzed by the Pig-a gene mutation assay and the micronucleus assay on peripheral blood, and by the alkaline comet, gpt mutation, and Spi(-) mutation assays on the liver. We also assessed the localization of TiO2 NPs in the liver, by transmission electron microscopy. Administration of TiO2 NPs did not significantly increase any of the following endpoints: frequency of Pig-a mutants (erythrocytes); frequency of micronuclei (reticulocytes); level of DNA damage (liver); frequencies of gpt and Spi(-) mutants (liver). Most TiO2 NPs in the liver were found in the sinuses and inside Kupffer cells, although some were occasionally observed in liver parenchymal cells. These results indicate that TiO2 NPs do not have genotoxic effects on mouse liver or bone marrow. PMID:27169374

  4. Heavy-ion-induced mutations in the gpt delta transgenic mouse: effect of p53 gene knockout.

    PubMed

    Yatagai, Fumio; Kurobe, Toshihiro; Nohmi, Takehiko; Masumura, Ken-ichi; Tsukada, Teruyo; Yamaguchi, Hirotake; Kasai-Eguchi, Kiyomi; Fukunishi, Nobuhisa

    2002-01-01

    The influence of the loss of p53 gene on heavy-ion-induced mutations was examined by constructing a new line of transgenic mice, p53 knockout (p53(-/-)) gpt delta. In this mouse model, deletions in lambda DNA integrated into the mouse genome are preferentially selected as Spi(-) phages, which can then be subjected to molecular analysis. Mice were exposed to 10 Gy of whole-body carbon-ion irradiation. The carbon ions were accelerated to 135 MeV/u by the RIKEN Ring Cyclotron. The p53 defect markedly enhanced the Spi(-) mutant frequency (MF) in the kidneys of mice exposed to C-ion irradiation: the Spi(-) MF increased 4.4- and 2.8-fold over the background level after irradiation in p53(-/-) and p53(+/+) mice, respectively. There was no significant difference in the background Spi(-) MF between p53(-/-) and p53(+/+) mice. Sequence analysis of the Spi(-) mutants indicated that the enhancement of kidney Spi(-) MF in p53(-/-) mice was primarily due to an increase in complex or rearranged-type deletions. In contrast to the kidney, the p53 defect had no effect on the Spi(-) MF in liver: Spi(-) MF increased 3.0- and 2.7-fold after the irradiation in p53(-/-) and p53(+/+) mice, respectively. Our results suggest that p53 suppresses deletion mutations induced by heavy-ion irradiation in an organ-specific manner. PMID:12355556

  5. Validation study of the combined repeated-dose toxicity and genotoxicity assay using gpt delta rats

    PubMed Central

    Akagi, Jun-ichi; Toyoda, Takeshi; Cho, Young-Man; Mizuta, Yasuko; Nohmi, Takehiko; Nishikawa, Akiyoshi; Ogawa, Kumiko

    2015-01-01

    Transgenic rodents carrying reporter genes to detect organ-specific in vivo genetic alterations are useful for risk assessment of genotoxicity that causes cancer. Thus, the Organization for Economic Co-operation and Development has established the guideline for genotoxicity tests using transgenic animals, which may be combined with repeated-dose toxicity studies. Here, we provide evidence to support equivalence of gpt delta and wild type (WT) rats in terms of toxicological responses to a genotoxic hepatocarcinogen, N-nitrosodiethylamine (DEN), and a non-genotoxic hepatocarcinogen, di(2-ethylhexyl)phthalate (DEHP). gpt delta rats treated with DEHP showed similar increases in liver and kidney weights, serum albumin, albumin/globulin ratios, and incidence of diffuse hepatocyte hypertrophy compared to WT F344 and Sprague–Dawley (SD) rats. DEN-treated gpt delta rats showed equivalent increases in the number and area of precancerous GST-P-positive foci in the liver compared to WT rats. The livers of DEN-treated gpt delta rats also showed increased frequencies of gpt and Spi− mutations; such changes were not observed in DEHP-treated gpt delta rats. These results indicated that gpt delta rats (both F344 and SD backgrounds) showed comparable DEHP-induced toxicity and DEN-induced genotoxicity to those observed in WT rats. With regard to the administration period, the general toxicity of 1.2% DEHP was evident throughout the experimental period, and the genotoxicity of 10 p.p.m. DEN could be detected after 2 weeks of administration and further increased at 4 weeks. These results suggested that combined assays using gpt delta rats could detect both general toxicity and genotoxicity by the canonical 4-week administration protocol. Therefore, this assay using gpt delta rats would be applicable for risk assessment including early detection of genotoxic carcinogens and ultimately serve to reduce cancer risks in humans from environmental chemicals. PMID:25683344

  6. Validation study of the combined repeated-dose toxicity and genotoxicity assay using gpt delta rats.

    PubMed

    Akagi, Jun-Ichi; Toyoda, Takeshi; Cho, Young-Man; Mizuta, Yasuko; Nohmi, Takehiko; Nishikawa, Akiyoshi; Ogawa, Kumiko

    2015-05-01

    Transgenic rodents carrying reporter genes to detect organ-specific in vivo genetic alterations are useful for risk assessment of genotoxicity that causes cancer. Thus, the Organization for Economic Co-operation and Development has established the guideline for genotoxicity tests using transgenic animals, which may be combined with repeated-dose toxicity studies. Here, we provide evidence to support equivalence of gpt delta and wild type (WT) rats in terms of toxicological responses to a genotoxic hepatocarcinogen, N-nitrosodiethylamine (DEN), and a non-genotoxic hepatocarcinogen, di(2-ethylhexyl)phthalate (DEHP). gpt delta rats treated with DEHP showed similar increases in liver and kidney weights, serum albumin, albumin/globulin ratios, and incidence of diffuse hepatocyte hypertrophy compared to WT F344 and Sprague-Dawley (SD) rats. DEN-treated gpt delta rats showed equivalent increases in the number and area of precancerous GST-P-positive foci in the liver compared to WT rats. The livers of DEN-treated gpt delta rats also showed increased frequencies of gpt and Spi(-) mutations; such changes were not observed in DEHP-treated gpt delta rats. These results indicated that gpt delta rats (both F344 and SD backgrounds) showed comparable DEHP-induced toxicity and DEN-induced genotoxicity to those observed in WT rats. With regard to the administration period, the general toxicity of 1.2% DEHP was evident throughout the experimental period, and the genotoxicity of 10 p.p.m. DEN could be detected after 2 weeks of administration and further increased at 4 weeks. These results suggested that combined assays using gpt delta rats could detect both general toxicity and genotoxicity by the canonical 4-week administration protocol. Therefore, this assay using gpt delta rats would be applicable for risk assessment including early detection of genotoxic carcinogens and ultimately serve to reduce cancer risks in humans from environmental chemicals. PMID:25683344

  7. Transgenic Chinese hamster V79 cell lines which exhibit variable levels of gpt mutagenesis

    SciTech Connect

    Klein, C.B.; Rossman, T.G. )

    1990-01-01

    The Escherichia coli gpt gene coding for xanthine-guanine phosphoribosyl transferase has been stably transfected into HPRT{sup {minus}} Chinese hamster V79 cells. Several gpt{sup {minus}} cell lines have been established, which retain the sequence(s) even after long-term culture without selection for gpt. While spontaneous mutagenesis to gpt{sup {minus}} occurs rather frequently for most cell lines, it cannot be correlated with either the number of plasmid integration sites or deletion of the plasmid sequence(s). One transgenic cell line (g12), which continuously maintains a low spontaneous mutation frequency was used in comparative mutagenesis studies with wild-type V79 cells (gpt vs. hprt). Alkylating agents such as N-methyl-N{prime}-nitro-N-nitrosoguanidine (MNNG) and {beta}-propiolactone (BPL) are shown to be equally toxic and mutagenic in both g12 and V79 cells. UV and X-rays are also equally toxic to both cell lines. The data presented here suggests that g12 cells may be useful to study mammalian mutagenesis by agents which yield limited response at the hprt locus.

  8. Chemical structure-related mechanisms underlying in vivo genotoxicity induced by nitrofurantoin and its constituent moieties in gpt delta rats.

    PubMed

    Kijima, Aki; Ishii, Yuji; Takasu, Shinji; Matsushita, Kohei; Kuroda, Ken; Hibi, Daisuke; Suzuki, Yuta; Nohmi, Takehiko; Umemura, Takashi

    2015-05-01

    Nitrofurans are antimicrobial compounds containing a nitro group at the 5-position of the furan ring and an amine or hydrazide side chain derivative. One member of the nitrofurans, nitrofurantoin (NFT), is a renal carcinogen in male rats despite its still controversial genotoxicity. We investigated chemical structure-related modes of action of NFT, and reporter gene mutation assays for NFT and its constituent moieties were performed. NFT, 5-nitro-2-furaldehyde (NFA), or 1-aminohydantoin (AHD) was administered to male F344 gpt delta rats by gavage for 4 or 13 weeks at a carcinogenic or the maximum tolerated dose. NFT caused a significant increase in gpt mutant frequency (MF) at 13 weeks with G-base substitution mutations. An increase in gpt MF was also observed in the NFA-treated group at 13 weeks, but not in the AHD-treated group. 8-Hydroxydeoxyguanosine (8-OHdG) levels in the kidney DNA of NFT-treated rats were significantly increased after 4 weeks. NFT caused accumulation of hyaline droplets indicated by positive immunostaining and western blot analysis for α2u-globulin in the proximal tubules. An additional study, in which female gpt delta rats were given NFT at the same dose used for males, was performed to mitigate the effect of α2u-globulin. NFT exerted the same effects on female rat kidneys to the same extent as males in terms of gpt MF and 8-OHdG level. Thus, it is highly probable that the structure of the nitro furan plays a key role in NFT-induced genotoxicity and genotoxic mechanisms including oxidative DNA damage are involved in NFT-induced renal carcinogenesis. α2u-globulin-mediated nephropathy may be a prerequisite for NFT-induced renal carcinogenesis in male rats, and additionally NFT could be a latent carcinogen in female rats and other animal species. PMID:25772432

  9. Reporter gene mutation in the livers of gpt delta mice treated with 5-(hydroxymethyl)-2-furfural, a contaminant of various foods.

    PubMed

    Matsushita, Kohei; Ishii, Yuji; Kijima, Aki; Jin, Meilan; Takasu, Shinji; Kuroda, Ken; Kodama, Yukio; Ogawa, Kumiko; Umemura, Takashi

    2012-01-01

    A major product formed during the Maillard reaction is 5-(hydroxymethyl)-2-furfural (HMF), which is present in various foods and beverages such as honey and fruit juice. HMF was shown to be a hepatocarcinogen in female mice using long-term bioassays. Although HMF is not a mutagen in conventional in vitro mutation assays, 5-sulfoxymethylfurfural (SMF), a reactive metabolite of HMF produced following sulfotransferase conjugation, does show mutagenicity. Thus, HMF-induced hepatocarcinogenesis likely involves genotoxic mechanisms. To clarify the mechanisms underlying HMF-induced hepatocarcinogenesis, female B6C3F(1) gpt delta mice were given HMF at carcinogenic doses (188 or 375 mg/kg b.w.) by gavage for 5 days per week for 4 weeks. This treatment produced no significant differences in mutant frequencies (MFs) of gpt and red/gam (Spi(-)) genes among the groups. These results suggest that genotoxicity does not contribute to HMF-induced hepatocarcinogenesis. Parameters related to cell proliferation, such as proliferation cell nuclear antigen-labeling index and Cyclin D1 and E1 mRNA expression, exhibited no significant changes in the livers of HMF-treated groups. In view of the lack of carcinogenicity in rats, HMF may be considered to be a weak carcinogen. These results help us to understand the underlying mechanisms of action of HMF carcinogenesis. PMID:23038016

  10. TRANSGENIC PLANTS EXPRESSING BACILLUS THURINGIENSIS DELTA-ENDOTOXINS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercial varieties of transgenic Bacillus thuringiensis (Bt) plants have been developed in many countries to control target pests. Initially, the expression of native Bt genes in plants was low due to mRNA instability, improper splicing, and post-translation modifications. Subsequently, modificati...

  11. A delta T-cell receptor deleting element transgenic reporter construct is rearranged in alpha beta but not gamma delta T-cell lineages.

    PubMed Central

    Shutter, J; Cain, J A; Ledbetter, S; Rogers, M D; Hockett, R D

    1995-01-01

    T cells can be divided into two groups on the basis of the expression of either alpha beta or gamma delta T-cell receptors (TCRs). Because the TCR delta chain locus lies within the larger TCR alpha chain locus, control of the utilization of these two receptors is important in T-cell development, specifically for determination of T-cell type: rearrangement of the alpha locus results in deletion of the delta coding segments and commitment to the alpha beta lineage. In the developing thymus, a relative site-specific recombination occurs by which the TCR delta chain gene segments are deleted. This deletion removes all D delta, J delta, and C delta genes and occurs on both alleles. This delta deletional mechanism is evolutionarily conserved between mice and humans. Transgenic mice which contain the human delta deleting elements and as much internal TCR delta chain coding sequence as possible without allowing the formation of a complete delta chain gene were developed. Several transgenic lines showing recombinations between deleting elements within the transgene were developed. These lines demonstrate that utilization of the delta deleting elements occurs in alpha beta T cells of the spleen and thymus. These recombinations are rare in the gamma delta population, indicating that the machinery for utilization of delta deleting elements is functional in alpha beta T cells but absent in gamma delta T cells. Furthermore, a discrete population of early thymocytes containing delta deleting element recombinations but not V alpha-to-J alpha rearrangements has been identified. These data are consistent with a model in which delta deletion contributes to the implementation of a signal by which the TCR alpha chain locus is rearranged and expressed and thus becomes an alpha beta T cell. PMID:8524269

  12. Transgenic mice support replication of hepatitis delta virus RNA in multiple tissues, particularly in skeletal muscle.

    PubMed Central

    Polo, J M; Jeng, K S; Lim, B; Govindarajan, S; Hofman, F; Sangiorgi, F; Lai, M M

    1995-01-01

    Hepatitis delta virus (HDV) is hepatotropic and frequently causes fulminant hepatitis in both human and nonhuman primate hosts. To understand the molecular basis of HDV tissue tropism and the mechanism of pathogenesis, transgenic mice in which replication-competent HDV dimeric RNA is expressed under the control of either liver-specific or universal transcriptional promoters were developed. The expressed RNA replicated efficiently in the liver and several tissues of nonhepatic origin. Surprisingly, maximal replication of HDV RNA occurred in skeletal muscle and was almost 100-fold greater than in the liver. These findings suggest that the hepatotropism of HDV is most likely a receptor-mediated restriction and that muscle-specific factors may facilitate HDV RNA replication. No evidence of cytopathology was apparent in most of the tissues examined, including the liver, supporting the contention that hepatocellular disease is not mediated by direct cytopathological effects associated with HDV RNA replication and gene expression. However, mild muscle atrophy in some of the transgenic mice was noted. Delta antigen was detected in the nuclei of myocytes. Only the small form, not the large form, of delta antigen was detected, suggesting that the RNA editing event which causes the conversion of delta antigen did not occur in transgenic mice. Furthermore, the 0.8-kb antigenomic RNA species, which is postulated to be the mRNA for delta antigen, was not detected in mice. The preferential replication of HDV RNA in skeletal muscle suggests that HDV RNA replication can be facilitated by certain muscle-specific factors. PMID:7609056

  13. Cell-autonomous alteration of dopaminergic transmission by wild type and mutant (DeltaE) TorsinA in transgenic mice.

    PubMed

    Page, Michelle E; Bao, Li; Andre, Pierrette; Pelta-Heller, Joshua; Sluzas, Emily; Gonzalez-Alegre, Pedro; Bogush, Alexey; Khan, Loren E; Iacovitti, Lorraine; Rice, Margaret E; Ehrlich, Michelle E

    2010-09-01

    Early onset torsion dystonia is an autosomal dominant movement disorder of variable penetrance caused by a glutamic acid, i.e. DeltaE, deletion in DYT1, encoding the protein TorsinA. Genetic and structural data implicate basal ganglia dysfunction in dystonia. TorsinA, however, is diffusely expressed, and therefore the primary source of dysfunction may be obscured in pan-neuronal transgenic mouse models. We utilized the tyrosine hydroxylase (TH) promoter to direct transgene expression specifically to dopaminergic neurons of the midbrain to identify cell-autonomous abnormalities. Expression of both the human wild type (hTorsinA) and mutant (DeltaE-hTorsinA) protein resulted in alterations of dopamine release as detected by microdialysis and fast cycle voltammetry. Motor abnormalities detected in these mice mimicked those noted in transgenic mice with pan-neuronal transgene expression. The locomotor response to cocaine in both TH-hTorsinA and TH-DeltaE-hTorsinA, in the face of abnormal extracellular DA levels relative to non-transgenic mice, suggests compensatory, post-synaptic alterations in striatal DA transmission. This is the first cell-subtype-specific DYT1 transgenic mouse that can serve to differentiate between primary and secondary changes in dystonia, thereby helping to target disease therapies. PMID:20460154

  14. [Expression of Mortierella isabellina delta6-fatty acid desaturase gene in gamma-linolenic acid production in transgenic tobacco].

    PubMed

    Li, Ming-Chun; Liu, Li; Hu, Guo-Wu; Xing, Lai-Jun

    2003-03-01

    Gamma-linolenic acid (GLA, C18:3delta6.9.12) is nutritional and important polyunsaturated fatty acid in human and animal diets. GLA play an important role in hormone regulation and fatty acid metabolization. Furthermore it is also the biological precursor of a group of molecules, including prostaglandins, leukotrienes and thromboxanes. Vast majority of oilseed crops do not produce GLA, but linoleic acid (LA, C18:2delta9.12) as its substrate. GLA is only produced by a small number of oilseed plants such as evening promrose ( Oenotheera spp.), borage (Borago officinalis) and etc. delta6-fatty acid desaturase (D6D) is the rate-limiting enzyme in the production of GLA. It can convert from linoleic acid to linolenic acid. To produce GLA in tobacco, plant expression vector was first constructed. To facilitate preparation of plant expression constructs, flanking Xba I and Bgl II restriction enzyme sites were added to the coding region of clone pTMICL6 by PCR amplification. pTMICL6 contains delta6-fatty acid desaturase gene cloned from Mortierella isabellina which is an oil-producing fugus. The PCR product was purified and subcloned into the plant expression vector pGA643 to generate the recombinant vector pGAMICL6 which contains the ORF of the D6D gene of Mortierella isabellina, together with regulatory elements consisting of the cauliflower mosaic virus 35S promoter and the nopaline synthase (nos) termination sequence. The plasmid pGAMICL6 was transformed into Agrobacterium tumefaciens strain LBA4404 by method of freeze thawing of liquid nitrogen. Transformants were selected by plating on YEB medium plates containing kanamycin and streptomycin and grown overnight at 28 degrees C, then transformants were further identified by PCR. The positive transformant containing the plant expression vector pGAMICL6 was transformed into tobacco ( Nicotiana tabacum cv. Xanthi) via Agrobacterium infection. Transgenic plants were selected on 100 microg/mL kanamycin. Plants were

  15. Co-expression of the borage Delta 6 desaturase and the Arabidopsis Delta 15 desaturase results in high accumulation of stearidonic acid in the seeds of transgenic soybean.

    PubMed

    Eckert, Helene; La Vallee, Brad; Schweiger, Bruce J; Kinney, Anthony J; Cahoon, Edgar B; Clemente, Tom

    2006-10-01

    Two relatively rare fatty acids, gamma-linolenic acid (GLA) and stearidonic acid (STA), have attracted much interest due to their nutraceutical and pharmaceutical potential. STA, in particular, has been considered a valuable alternative source for omega-3 fatty acids due to its enhanced conversion efficiency in animals to eicosapentaenoic acid when compared with the more widely consumed omega-3 fatty acid, alpha-linolenic acid (ALA), present in most vegetable oils. Exploiting the wealth of information currently available on in planta oil biosynthesis and coupling this information with the tool of genetic engineering it is now feasible to deliberately perturb fatty acid pools to generate unique oils in commodity crops. In an attempt to maximize the STA content of soybean oil, a borage Delta(6) desaturase and an Arabidopsis Delta(15) desaturase were pyramided by either sexual crossing of transgenic events, re-transformation of a Delta(6) desaturase event with the Delta(15) desaturase or co-transformation of both desaturases. Expression of both desaturases in this study was under the control of the seed-specific soybean beta-conglycinin promoter. Soybean events that carried only the Delta(15 )desaturase possessed a significant elevation of ALA content, while events with both desaturases displayed a relative STA abundance greater than 29%, creating a soybean with omega-3 fatty acids representing over 60% of the fatty acid profile. Analyses of the membrane lipids in a subset of the transgenic events suggest that soybean seeds compensate for enhanced production of polyunsaturated fatty acids by increasing the relative content of palmitic acid in phosphatidylcholine and other phospholipids. PMID:16718484

  16. Overexpression of [delta]-Pyrroline-5-Carboxylate Synthetase Increases Proline Production and Confers Osmotolerance in Transgenic Plants.

    PubMed Central

    Kishor, PBK.; Hong, Z.; Miao, G. H.; Hu, CAA.; Verma, DPS.

    1995-01-01

    Proline (Pro) accumulation has been correlated with tolerance to drought and salinity stresses in plants. Therefore, overproduction of Pro in plants may lead to increased tolerance against these abiotic stresses. To test this possibility, we overexpressed in tobacco the mothbean [delta]-pyrroline-5-carboxylate synthetase, a bifunctional enzyme able to catalyze the conversion of glutamate to [delta]-pyrroline-5-carboxylate, which is then reduced to Pro. The transgenic plants produced a high level of the enzyme and synthesized 10- to 18-fold more Pro than control plants. These results suggest that activity of the first enzyme of the pathway is the rate-limiting factor in Pro synthesis. Exogenous supply of nitrogen further enhanced Pro production. The osmotic potentials of leaf sap from transgenic plants were less decreased under water-stress conditions compared to those of control plants. Overproduction of Pro also enhanced root biomass and flower development in transgenic plants under drought-stress conditions. These data demonstrated that Pro acts as an osmoprotectant and that overproduction of Pro results in the increased tolerance to osmotic stress in plants. PMID:12228549

  17. Progressive paralysis associated with diffuse astrocyte anaplasia in delta 202 mice homozygous for a transgene encoding the SV40 T antigen.

    PubMed

    López-Revilla, Rubén; Soto-Zárate, Carlos; Ridaura, Cecilia; Chávez-Dueñas, Lucía; Paul, Dieter

    2004-03-01

    A convenient transgenic astrocytoma model in delta202 mice, homozygous for a construct encoding the early region of the SV40 virus genome, is described. In the offspring of crosses between delta202 mice heterozygous for the transgene nearly 60% were transgenic; one third of these developed progressive paralysis starting in the hindlimbs at approximately 35 days of age and died at 90 +/- 30 days of age. In affected mice proliferating-non-neuronal cells immunostained with antibodies to the GFAP, an astrocyte marker, whose number increased with age were found in the white matter of the brain, cerebellum and spinal cord, and progressive degeneration and necrosis of spinal motoneurons was observed that-may explain the paralysis. The early onset and reproducible time course of the neurological disease suggest that homozygous delta202 mice, whose proliferating astrocytes appear to damage spinal motoneurons, are a useful model to study astrocyte differentiation, function and tumorigenesis. PMID:15068170

  18. DHA diet reduces AD pathology in young APPswe/PS1 Delta E9 transgenic mice: possible gender effects.

    PubMed

    Perez, Sylvia E; Berg, Brian M; Moore, Kenneth A; He, Bin; Counts, Scott E; Fritz, Jason J; Hu, Yuan-Shih; Lazarov, Orly; Lah, James J; Mufson, Elliott J

    2010-04-01

    Epidemiological and clinical trial findings suggest that consumption of docosahexaenoic acid (DHA) lowers the risk of Alzheimer's disease (AD). We examined the effects of short-term (3 months) DHA enriched diet on plaque deposition and synaptic defects in forebrain of young APPswe/PS1 Delta E9 transgenic (tg) and non-transgenic (ntg) mice. Gas chromatography revealed a significant increase in DHA concomitant with a decrease of arachidonic acid in both brain and liver in mice fed with DHA. Female tg mice consumed relatively more food daily than ntg female mice, independent of diet. Plaque load was significantly reduced in the cortex, ventral hippocampus and striatum of female APPswe/PS1 Delta E9 tg mice on DHA diet compared to female tg mice on control diet. Immunoblot quantitation of the APOE receptor, LR11, which is involved in APP trafficking and A beta production, were unchanged in mice on DHA or control diets. Moreover drebrin levels were significantly increased in the hippocampus of tg mice on the DHA diet. Finally, in vitro DHA treatment prevented amyloid toxicity in cell cultures. Our findings support the concept that increased DHA consumption may play and important role in reducing brain insults in female AD patients. PMID:19859965

  19. QUANTIFICATION IN SOIL OF BACILLUS THURINGIENSIS VAR. KURSTAKI DELTA-ENDOTOXIN FROM TRANSGENIC PLANTS

    EPA Science Inventory

    Transgenic plants that produce pesticidal proteins have the potential to release these products into the environment when the plants are incorporated into soil. his could result in novel exposure of soil organisms to these pesticidal proteins. here is a lack of knowledge about th...

  20. Typing classical polymorphisms by real-time PCR: analysis of the GPT and ALAD protein polymorphisms in the Jewish populations.

    PubMed

    Zoossmann-Diskin, Avshalom; Swinburne, Sarah; Shohat, Mordechai; Peleg, Leah; Gazit, Ephraim; Turner, David

    2008-01-01

    Expanding the already extensive data array on classical polymorphisms in new populations is beneficial to full characterization of the intricate relationships between human populations. This can be done in a short time on a large-scale by using real-time PCR. The red-cell enzymes Delta-aminolevulinate dehydratase (ALAD) and glutamate pyruvate transaminase (GPT) have each two alleles that can be separated by protein electrophoresis. They were previously characterized by protein electrophoresis in some of the Jewish populations. We designed primers and probes for fluorescence resonance energy transfer detection of the ALAD and GPT alleles to type Jewish populations including some in which these polymorphisms have not been studied in the past. The methods described here allow fast and efficient determination of these common classical polymorphisms. When used in large-scale population studies, these methods are not only faster, but also cheaper than amplification followed by restriction enzyme digestion and gel electrophoresis. The frequency of ALAD*1 among Jews ranges from 0.781 to 0.960 and that of GPT*1 from 0.412 to 0.773. A maximum likelihood tree based on the ALAD and GPT polymorphisms and five other red-cells enzymes polymorphisms depicts quite accurately the known historic, anthropological, and geographic relations between the Jewish populations. PMID:18432999

  1. DELTAE

    SciTech Connect

    Ward, W.C.; Swift, G.W. )

    1993-11-01

    In thermoacoustic engines and refrigerators, and in many simple acoustic systems, a one dimensional wave equation determines the spatial dependence of the acoustic pressure and velocity. DELTAE numerically integrates such wave equations in the acoustic approximation, in gases or liquids, in user-defined geometries. Boundary conditions can include conventional acoustic boundary conditions of geometry and impedance, as well as temperature and thermal power in thermoacoustic systems. DELTAE can be used easily for apparatus ranging from simple duct networks and resonators to thermoacoustic engines refrigerators and combinations thereof. It can predict how a given apparatus will perform, or can allow the user to design an apparatus to achieve desired performance. DELTAE views systems as a series of segments; twenty segment types are supported. The purely acoustic segments include ducts and cones, and lumped impedances including compliances, series impedances, and endcaps. Electroacoustics tranducer segments can be defined using either frequency-independent coefficients or the conventional parameters of loudspeaker-style drivers: mass, spring constant, magnetic field strength, etc. Tranducers can be current driven, voltage driven, or connected to an electrical load impedance. Thermoacoustic segment geometries include parallel plates, circular and rectangular pores, and pin arrays. Side branches can be defined with fixed impedances, frequency-dependent radiation impedances, or as an auxiliary series of segments of any types. The user can select working fluids from among air, helium, neon, argon, hydrogen, deuterium, carbon dioxide, nitrogen, helium-argon mixtures, helium-xenon mixtures, liquid sodium, and eutectic sodium-potassium. Additional fluids and solids can be defined by the user.

  2. Nucleic acids encoding plant glutamine phenylpyruvate transaminase (GPT) and uses thereof

    DOEpatents

    Unkefer, Pat J.; Anderson, Penelope S.; Knight, Thomas J.

    2016-03-29

    Glutamine phenylpyruvate transaminase (GPT) proteins, nucleic acid molecules encoding GPT proteins, and uses thereof are disclosed. Provided herein are various GPT proteins and GPT gene coding sequences isolated from a number of plant species. As disclosed herein, GPT proteins share remarkable structural similarity within plant species, and are active in catalyzing the synthesis of 2-hydroxy-5-oxoproline (2-oxoglutaramate), a powerful signal metabolite which regulates the function of a large number of genes involved in the photosynthesis apparatus, carbon fixation and nitrogen metabolism.

  3. Noggin and BMP4 co-modulate adult hippocampal neurogenesis in the APP{sub swe}/PS1{sub {Delta}E9} transgenic mouse model of Alzheimer's disease

    SciTech Connect

    Tang, Jun; Song, Min; Wang, Yanyan; Fan, Xiaotang; Xu, Haiwei; Bai, Yun

    2009-07-31

    In addition to the subventricular zone, the dentate gyrus of the hippocampus is one of the few brain regions in which neurogenesis continues into adulthood. Perturbation of neurogenesis can alter hippocampal function, and previous studies have shown that neurogenesis is dysregulated in Alzheimer disease (AD) brain. Bone morphogenetic protein-4 (BMP4) and its antagonist Noggin have been shown to play important roles both in embryonic development and in the adult nervous system, and may regulate hippocampal neurogenesis. Previous data indicated that increased expression of BMP4 mRNA within the dentate gyrus might contribute to decreased hippocampal cell proliferation in the APP{sub swe}/PS1{sub {Delta}E9} mouse AD model. However, it is not known whether the BMP antagonist Noggin contributes to the regulation of neurogenesis. We therefore studied the relative expression levels and localization of BMP4 and its antagonist Noggin in the dentate gyrus and whether these correlated with changes in neurogenesis in 6-12 mo old APP{sub swe}/PS1{sub {Delta}E9} transgenic mice. Bromodeoxyuridine (BrdU) was used to label proliferative cells. We report that decreased neurogenesis in the APP/PS1 transgenic mice was accompanied by increased expression of BMP4 and decreased expression of Noggin at both the mRNA and protein levels; statistical analysis showed that the number of proliferative cells at different ages correlated positively with Noggin expression and negatively with BMP4 expression. Intraventricular administration of a chimeric Noggin/Fc protein was used to block the action of endogenous BMP4; this resulted in a significant increase in the number of BrdU-labeled cells in dentate gyrus subgranular zone and hilus in APP/PS1 mice. These results suggest that BMP4 and Noggin co-modulate neurogenesis.

  4. Transgenic plants with enhanced growth characteristics

    DOEpatents

    Unkefer, Pat J.; Anderson, Penelope S.; Knight, Thomas J.

    2016-09-06

    The invention relates to transgenic plants exhibiting dramatically enhanced growth rates, greater seed and fruit/pod yields, earlier and more productive flowering, more efficient nitrogen utilization, increased tolerance to high salt conditions, and increased biomass yields. In one embodiment, transgenic plants engineered to over-express both glutamine phenylpyruvate transaminase (GPT) and glutamine synthetase (GS) are provided. The GPT+GS double-transgenic plants of the invention consistently exhibit enhanced growth characteristics, with T0 generation lines showing an increase in biomass over wild type counterparts of between 50% and 300%. Generations that result from sexual crosses and/or selfing typically perform even better, with some of the double-transgenic plants achieving an astounding four-fold biomass increase over wild type plants.

  5. Transgenic expression of delta-6 and delta-15 fatty acid desaturases enhances omega-3 polyunsaturated fatty acid accumulation in Synechocystis sp. PCC6803

    PubMed Central

    2014-01-01

    Background Polyunsaturated fatty acids (PUFAs), which contain two or more double bonds in their backbone, are the focus of intensive global research, because of their nutritional value, medicinal applications, and potential use as biofuel. However, the ability to produce these economically important compounds is limited, because it is both expensive and technically challenging to separate omega-3 polyunsaturated fatty acids (ω-3 PUFAs) from natural oils. Although the biosynthetic pathways of some plant and microalgal ω-3 PUFAs have been deciphered, current understanding of the correlation between fatty acid desaturase content and fatty acid synthesis in Synechocystis sp. PCC6803 is incomplete. Results We constructed a series of homologous vectors for the endogenous and exogenous expression of Δ6 and Δ15 fatty acid desaturases under the control of the photosynthesis psbA2 promoter in transgenic Synechocystis sp. PCC6803. We generated six homologous recombinants, harboring various fatty acid desaturase genes from Synechocystis sp. PCC6803, Gibberella fujikuroi and Mortierella alpina. These lines produced up to 8.9 mg/l of α-linolenic acid (ALA) and 4.1 mg/l of stearidonic acid (SDA), which are more than six times the corresponding wild-type levels, at 20°C and 30°C. Thus, transgenic expression of Δ6 and Δ15 fatty acid desaturases enhances the accumulation of specific ω-3 PUFAs in Synechocystis sp. PCC6803. Conclusions In the blue-green alga Synechocystis sp. PCC6803, overexpression of endogenous and exogenous genes encoding PUFA desaturases markedly increased accumulation of ALA and SDA and decreased accumulation of linoleic acid and γ-linolenic acid. This study lays the foundation for increasing the fatty acid content of cyanobacteria and, ultimately, for producing nutritional and medicinal products with high levels of essential ω-3 PUFAs. PMID:24581179

  6. Ribozymes targeted to stearoyl-ACP delta9 desaturase mRNA produce heritable increases of stearic acid in transgenic maize leaves.

    PubMed Central

    Merlo, A O; Cowen, N; Delate, T; Edington, B; Folkerts, O; Hopkins, N; Lemeiux, C; Skokut, T; Smith, K; Woosley, A; Yang, Y; Young, S; Zwick, M

    1998-01-01

    Ribozymes are RNAs that can be designed to catalyze the specific cleavage or ligation of target RNAs. We have explored the possibility of using ribozymes in maize to downregulate the expression of the stearoyl-acyl carrier protein (Delta9) desaturase gene. Based on site accessibility and catalytic activity, several ribozyme constructs were designed and transformed into regenerable maize lines. One of these constructs, a multimer hammerhead ribozyme linked to a selectable marker gene, was shown to increase leaf stearate in two of 13 maize lines. There were concomitant decreases in Delta9 desaturase mRNA and protein. The plants with the altered stearate phenotype were shown to express ribozyme RNA. The ribozyme-mediated trait was heritable, as evidenced by stearate increases in the leaves of the R1 plants derived from a high-stearate line. The increase in stearate correlated with the presence of the ribozyme gene. A catalytically inactive version of this ribozyme did not produce any significant effect in transgenic maize. This is evidence that ribozymes can be used to modulate the expression of endogenous genes in maize. PMID:9761789

  7. Intrachromosomal telomere-related sequences and gpt locus sensitivity to ionizing radiation

    SciTech Connect

    Oroskar, A.A.; Sedita, B.A; Schwartz, J.L.

    1994-12-31

    The Chinese hamster ovary cell line CHO-T510 contains a single copy of a stably integrated retroviral vector with a selectable marker, the E. coli xanthine-guanine phosphoribosyl transferase (gpt) gene. Previous studies on the CHO-T510 line showed that, in comparison with other genetic loci, the gpt locus was hypersensitive to mutation induction by ionizing radiation. Southern blot analyses of a set of 20-26 gpt{sup -} mutant lines, isolated as either spontaneous, gamma-induced, or alpha-radiation-induced mutants, indicated that 86-95% of these were complete vector deletions. The integrated gpt vector was localized by in situ hybridization to the q arm of chromosome 5 in close proximity to the interstitial ttelomeresequences near the pericentric region of this chromosome. One to three kilobases of sequences adjacent to the gpt integration site were clones and analyzed. Both the right and left integration sites contain sequences that hybridize to a pantelomere probe, suggesting that the vector has acquired telomeric repeats at its ends. The radio-sensitivity of the gpt locus may be due to these telomere repeats, as interstitial telomeres have been reported to be radiation-sensitive fragile sites. The gpt locus in the T510 line affords a unique resource to test this hypothesis.

  8. GPT2: Empirical slant delay model for radio space geodetic techniques

    PubMed Central

    Lagler, K; Schindelegger, M; Böhm, J; Krásná, H; Nilsson, T

    2013-01-01

    Up to now, state-of-the-art empirical slant delay modeling for processing observations from radio space geodetic techniques has been provided by a combination of two empirical models. These are GPT (Global Pressure and Temperature) and GMF (Global Mapping Function), both operating on the basis of long-term averages of surface values from numerical weather models. Weaknesses in GPT/GMF, specifically their limited spatial and temporal variability, are largely eradicated by a new, combined model GPT2, which provides pressure, temperature, lapse rate, water vapor pressure, and mapping function coefficients at any site, resting upon a global 5° grid of mean values, annual, and semi-annual variations in all parameters. Built on ERA-Interim data, GPT2 brings forth improved empirical slant delays for geophysical studies. Compared to GPT/GMF, GPT2 yields a 40% reduction of annual and semi-annual amplitude differences in station heights with respect to a solution based on instantaneous local pressure values and the Vienna mapping functions 1, as shown with a series of global VLBI (Very Long Baseline Interferometry) solutions. PMID:25821263

  9. Targeted ablation and reorganization of the principal preplate neurons and their neuroblasts identified by golli promoter transgene expression in the neocortex of mice

    PubMed Central

    Xie, Yuan-Yun; Jacobs, Erin; Fisher, Robin

    2009-01-01

    The present study delineates the cellular responses of dorsal pallium to targeted genetic ablation of the principal preplate neurons of the neocortex. Ganciclovir treatment during prenatal development (E11–E13; where E is embryonic day) of mice selectively killed cells with shared S-phase vulnerability and targeted expression of a GPT [golli promoter transgene, linked to HSV-TK (herpes simplex virus-thymidine kinase), τ-eGFP (τ-enhanced green fluorescent protein) and lacZ (lacZ galactosidase) reporters] localized in preplate neurons. Morphogenetic fates of attacked neurons and neuroblasts, and their successors, were assessed by multiple labelling in time-series comparisons between ablated (HSV-TK+/0) and control (HSV-TK0/0) littermates. During ablation generation, neocortical growth was suppressed, and compensatory reorganization of non-GPT ventricular zone progenitors of dorsal pallium produced replacements for killed GPT neuroblasts. Replacement and surviving GPT neuroblasts then produced replacements for killed GPT neurons. Near-normal restoration of their complement delayed the settlement of GPT neurons into the reconstituted preplate, which curtailed the outgrowth of pioneer corticofugal axons. Based on this evidence, we conclude that specific cell killing in ablated mice can eliminate a major fraction of GPT neurons, with insignificant bystander killing. Also, replacement GPT neurons in ablated mice originate exclusively by proliferation from intermediate progenitor GPT neuroblasts, whose complement is maintained by non-GPT progenitors for inductive regulation of the total complement of GPT neurons. Finally, GPT neurons in both normal and ablated mice meet all morphogenetic criteria, including the ‘outside-in’ vertical gradient of settlement, presently used to identify principal preplate neurons. In ablated mice, delayed organization of these neurons desynchronizes and isolates developing neocortex from the rest of the brain, and permanently impairs

  10. GPT2/GMF2: An improved empirical model for tropospheric delays

    NASA Astrophysics Data System (ADS)

    Boehm, J.; Lagler, K.; Schindelegger, M.; Krasna, H.

    2012-12-01

    Troposphere delay modelling is a major error source in the analysis of space geodetic observations at radio wavelengths, like those from Global Navigation Satellite Systems (GNSS) or Very Long Baseline Interferometry (VLBI). If available, it is recommended to use pressure values recorded at the geodetic sites to determine zenith hydrostatic delays, to map those delays down to the elevation of the observation with the hydrostatic Vienna Mapping Function 1 (VMF1), and to estimate the residual zenith wet delay with the wet VMF1 in a least-squares adjustment. In case that neither local pressure values nor VMF1 are available, the analyst is advised to take the empirical functions, like the Global Pressure and Temperature (GPT) model and the Global Mapping Functions (GMF). Both, GPT and GMF, are built on spherical harmonics up to degree and order nine and they describe the annual variation of pressure, temperature, and the mapping function coefficients. Here, we present an updated version of GPT and GMF, called GPT2/GMF2, which has been obtained from 10 years of monthly climatological means as portrayed by ERA-Interim data of the ECMWF (European Centre for Medium-Range Weather Forecasts). GPT2/GMF2 is based on 5 x 5 degree grids, sine and cosine amplitudes for the annual and semi-annual variation of pressure, temperature, lapse rate, humidity, and mapping function coefficients. We show its implementation and application in the Vienna VLBI Software (VieVS) and compare the station coordinates and zenith delays against those determined with GPT/GMF or the VMF1 with local pressure measurements.

  11. Aspartate Aminotransferase (AST/GOT) and Alanine Aminotransferase (ALT/GPT) Detection Techniques

    PubMed Central

    Huang, Xing-Jiu; Choi, Yang-Kyu; Im, Hyung-Soon; Yarimaga, Oktay; Yoon, Euisik; Kim, Hak-Sung

    2006-01-01

    The levels of aspartate aminotransferase (AST/GOT) and alanine aminotransferase (ALT/GPT) in serum can help people diagnose body tissues especially the heart and the liver are injured or not. This article provides a comprehensive review of research activities that concentrate on AST/GOT and ALT/GPT detection techniques due to their clinical importance. The detection techniques include colorimetric, spectrophotometric, chemiluminescence, chromatography, fluorescence and UV absorbance, radiochemical, and electrochemical techniques. We devote the most attention on experimental principle. In some methods a few representative devices and important conclusions are presented.

  12. Serum Glutamic-Oxaloacetic Transaminase (GOT) and Glutamic-Pyruvic Transaminase (GPT) Levels in Children and Adolescents with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Lin, Jin-Ding; Lin, Pei-Ying; Chen, Li-Mei; Fang, Wen-Hui; Lin, Lan-Ping; Loh, Ching-Hui

    2010-01-01

    The elevated serum glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) rate among people with intellectual disabilities (ID) is unknown and have not been sufficiently studies. The present paper aims to provide the profile of GOT and GPT, and their associated relationship with other biochemical levels of children or…

  13. Loss of function mutation in glutamic pyruvate transaminase 2 (GPT2) causes developmental encephalopathy

    PubMed Central

    Celis, Katrina; Shuldiner, Scott; Haverfield, Eden V.; Cappell, Joshua; Yang, Rongze; Gong, Da-Wei

    2016-01-01

    Intellectual disability is genetically heterogeneous, and it is likely that many of the responsible genes have not yet been identified. We describe three siblings with isolated, severe developmental encephalopathy. After extensive uninformative genetic and metabolic testing, whole exome sequencing identified a homozygous novel variant in glutamic pyruvate transaminase 2 (GPT2) or alanine transaminase 2 (ALT2), c.459 C>G p.Ser153Arg that segregated with developmental encephalopathy in the family. This variant was predicted to be damaging by all in silico prediction algorithms. GPT2 is the gene encoding ALT2 which is responsible for the reversible transamination of alanine and 2-oxoglutarate to form pyruvate and glutamate. GPT2 is expressed in brain and is in the pathway to generate glutamate, an excitatory neurotransmitter. Functional assays of recombinant wild-type and mutant ALT2 proteins demonstrated the p.Ser153Arg mutation resulted in a severe loss of enzymatic function. We suggest that recessively inherited loss of function GPT2 mutations are a novel cause of intellectual disability. PMID:25758935

  14. Metal mutagenesis in transgenic Chinese hamster cell lines.

    PubMed Central

    Klein, C B; Kargacin, B; Su, L; Cosentino, S; Snow, E T; Costa, M

    1994-01-01

    Metals are toxic agents for which genotoxic effects are often difficult to demonstrate. To study metal mutagenesis, we have used two stable hprt/gpt+ transgenic cell lines that were derived from Chinese hamster V79 cells. Both the G12 and G10 cell lines are known to be very sensitive to clastogens such as X-rays and bleomycin, with the mutagenic response of the integrated xanthine guanine phosphoribosyl transferase (gpt) gene in G10 usually exceeding that of the same gene in the transgenic G12 cells. In studies with carcinogenic insoluble nickel compounds, a high level of mutagenesis was found at the gpt locus of G12 cells but not at the endogenous hypoxanthine phosphoribosyl transferase (hprt) locus of V79 cells. We have since demonstrated the similar recovery of a high frequency of viable G12 mutants with other insoluble nickel salts including nickel oxides (black and green). The relative mutant yield for the insoluble nickel compounds (G12 > G10) is the opposite of that obtained with nonmetal clastogens (G10 > G12). In the G12 cells, nickel mutagenesis may be related to the integration of the gpt sequence into a heterochromatic region of the genome. For some of the insoluble nickel compounds, significant inhibition of both cytotoxicity and mutant yield resulted when the G12 cells were pretreated with vitamin E. In comparison with the nickel studies, the mutagenic responses to chromium compounds in these cell lines were not as dramatic. Mutagenesis of the gpt target could not be demonstrated with other metals such as mercury or vanadium. PMID:7843139

  15. Acclimation of metabolism to light in A rabidopsis thaliana: the glucose 6‐phosphate/phosphate translocator GPT2 directs metabolic acclimation

    PubMed Central

    DYSON, BETH C.; ALLWOOD, J. WILLIAM; FEIL, REGINA; XU, YUN; MILLER, MATTHEW; BOWSHER, CAROLINE G.; GOODACRE, ROYSTON; LUNN, JOHN E.

    2015-01-01

    Abstract Mature leaves of plants transferred from low to high light typically increase their photosynthetic capacity. In A rabidopsis thaliana, this dynamic acclimation requires expression of GPT2, a glucose 6‐phosphate/phosphate translocator. Here, we examine the impact of GPT2 on leaf metabolism and photosynthesis. Plants of wild type and of a GPT2 knockout (gpt2.2) grown under low light achieved the same photosynthetic rate despite having different metabolic and transcriptomic strategies. Immediately upon transfer to high light, gpt2.2 plants showed a higher rate of photosynthesis than wild‐type plants (35%); however, over subsequent days, wild‐type plants acclimated photosynthetic capacity, increasing the photosynthesis rate by 100% after 7 d. Wild‐type plants accumulated more starch than gpt2.2 plants throughout acclimation. We suggest that GPT2 activity results in the net import of glucose 6‐phosphate from cytosol to chloroplast, increasing starch synthesis. There was clear acclimation of metabolism, with short‐term changes typically being reversed as plants acclimated. Distinct responses to light were observed in wild‐type and gpt2.2 leaves. Significantly higher levels of sugar phosphates were observed in gpt2.2. We suggest that GPT2 alters the distribution of metabolites between compartments and that this plays an essential role in allowing the cell to interpret environmental signals. PMID:25474495

  16. Transgenic Fish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fish into which foreign DNA is artificially introduced and integrated into their genome are called transgenic fish. Since the development of the first transgenic fish in 1985, techniques to produce transgenic fish have improved tremendously, resulting in the production of genetically modified (GM) ...

  17. Human glutamate pyruvate transaminase (GPT): Localization to 8q24.3, cDNA and genomic sequences, and polymorphic sites

    SciTech Connect

    Sohocki, M.M.; Sullivan, L.S.; Daiger, S.P.

    1997-03-01

    Two frequent protein variants of glutamate pyruvate transaminase (GPT) (E.C.2.6.1.2) have been used as genetic markers in humans for more than two decades, although chromosomal mapping of the GPT locus in the 1980s produced conflicting results. To resolve this conflict and develop useful DNA markers for this gene, we isolated and characterized cDNA and genomic clones of GPT. We have definitively mapped human GPT to the terminus of 8q using several methods. First, two cosmids shown to contain the GPT sequence were derived from a chromosome 8-specific library. Second, by fluorescence in situ hybridization, we mapped the cosmid containing the human GPT gene to chromosome band 8q24.3. Third, we mapped the rat gpt cDNA to the syntenic region of rat chromosome 7. Finally, PCR primers specific to human GPT amplify sequences contained within a {open_quotes}half-YAC{close_quotes} from the long arm of chromosome 8, that is, a YAC containing the 8q telomere. The human GPT genomic sequence spans 2.7 kb and consists of 11 exons, ranging in size from 79 to 243 bp. The exonic sequence encodes a protein of 495 amino acids that is nearly identical to the previously reported protein sequence of human GPT-1. The two polymorphic GPT isozymes are the result of a nucleotide substitution in codon 14. In addition, a cosmid containing the GPT sequence also contains a previously unmapped, polymorphic microsatellite sequence, D8S421. The cloned GPT gene and associated polymorphisms will be useful for linkage and physical mapping of disease loci that map to the terminus of 8q, including atypical vitelliform macular dystrophy (VMD1) and epidermolysis bullosa simplex, type Ogna (EBS1). In addition, this will be a useful system for characterizing the telomeric region of 8q. Finally, determination of the molecular basis of the GPT isozyme variants will permit PCR-based detection of this world-wide polymorphism. 22 refs., 3 figs.

  18. Delta-Aminolevulinate-Induced Host-Parasite Porphyric Disparity for Selective Photolysis of Transgenic Leishmania in the Phagolysosomes of Mononuclear Phagocytes: a Potential Novel Platform for Vaccine Delivery

    PubMed Central

    Dutta, Sujoy; Chang, Celia; Kolli, Bala Krishna; Sassa, Shigeru; Yousef, Malik; Showe, Michael; Showe, Louise

    2012-01-01

    Leishmania double transfectants (DTs) expressing the 2nd and 3rd enzymes in the heme biosynthetic pathway were previously reported to show neogenesis of uroporphyrin I (URO) when induced with delta-aminolevulinate (ALA), the product of the 1st enzyme in the pathway. The ensuing accumulation of URO in DT promastigotes rendered them light excitable to produce reactive oxygen species (ROS), resulting in their cytolysis. Evidence is presented showing that the DTs retained wild-type infectivity to their host cells and that the intraphagolysosomal/parasitophorous vacuolar (PV) DTs remained ALA inducible for uroporphyrinogenesis/photolysis. Exposure of DT-infected cells to ALA was noted by fluorescence microscopy to result in host-parasite differential porphyrinogenesis: porphyrin fluorescence emerged first in the host cells and then in the intra-PV amastigotes. DT-infected and control cells differed qualitatively and quantitatively in their porphyrin species, consistent with the expected multi- and monoporphyrinogenic specificities of the host cells and the DTs, respectively. After ALA removal, the neogenic porphyrins were rapidly lost from the host cells but persisted as URO in the intra-PV DTs. These DTs were thus extremely light sensitive and were lysed selectively by illumination under nonstringent conditions in the relatively ROS-resistant phagolysosomes. Photolysis of the intra-PV DTs returned the distribution of major histocompatibility complex (MHC) class II molecules and the global gene expression profiles of host cells to their preinfection patterns and, when transfected with ovalbumin, released this antigen for copresentation with MHC class I molecules. These Leishmania mutants thus have considerable potential as a novel model of a universal vaccine carrier for photodynamic immunotherapy/immunoprophylaxis. PMID:22307976

  19. Nile Delta

    Atmospheric Science Data Center

    2013-04-15

    article title:  The Nile River Delta     View Larger Image ... of eastern Africa. At the apex of the fertile Nile River Delta is the Egyptian capital city of Cairo. To the west are the Great Pyramids ...

  20. Transgenic Animals.

    ERIC Educational Resources Information Center

    Jaenisch, Rudolf

    1988-01-01

    Describes three methods and their advantages and disadvantages for introducing genes into animals. Discusses the predictability and tissue-specificity of the injected genes. Outlines the applications of transgenic technology for studying gene expression, the early stages of mammalian development, mutations, and the molecular nature of chromosomes.…

  1. Evaluation of pressure extracted from NCEP and CMC global numerical weather prediction models against in-situ and GPT pressure

    NASA Astrophysics Data System (ADS)

    McAdam, M.; Chai, N.; Santos, M. C.

    2012-12-01

    An earlier investigation by Urquhart et al (2011) demonstrated that ray traced hydrostatic zenith delays from NCEP's Re-Analysis I (NCEP) dataset proved to exhibit higher variability when compared to those from the Canadian Meteorological Centre's (CMC) Global Deterministic Prediction System (GDPS) and the European Centre for Medium Range Weather Forecasting (ECMWF). This investigation expands on the original by analyzing the variation of the zenith hydrostatic delay (as ray traced through the NWP) and the extracted pressure at the surface for 35 IGS reference stations for the entire year of 2010. Two NWP's were selected, NCEP's Re-Analysis I and CMC's GDPS. NCEP was selected since it forms the basis for the UNB-VMF1 service, and CMC's GDPS was selected due to availability. Both models have global coverage, but NCEP's grid resolution is 2.5 x 2.5 degrees as compared to CMC's (GDPS) 0.6 x 0.6 degrees. The location within the NWP is defined by the location of the IGS reference stations. The position of the reference stations are defined by the IGS weekly solutions where week 52's coordinate values for the year 2010 were used. The height was then adjusted by the defined meteorological sensor offset as defined the IGS stations's respective log. The investigation is based on the following comparisons: 1. Extracted Pressure from the NWP (NCEP and CMC (GDPS)) compared to measured pressure from the site, and also from pressure derived from GPT model. 2. Raytraced hydrostatic zenith delay compared to the Saastamoinen hydrostatic zenith computed from the measured site pressure. Results indicate good agreement between pressure extracted from the NWP and in-situ pressure and larger differences with respect to GPT.

  2. Quantitative and molecular analyses of mutation in a pSV2gpt transformed CHO cell line

    SciTech Connect

    Stankowski, L.F. Jr.; Tindall, K.R.; Hsie, A.W.

    1983-01-01

    Following NDA-mediated gene transfer we have isolated a cell line useful for studying gene mutation at the molecular level. This line, AS52, derived from a hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficient Chinese hamster ovary (CHO) cell line, carries a single copy of the E. coli xanthine-guanine phosphoribosyl transferase (XGPRT) gene (gpt) and exhibits a spontaneous mutant frequency of 20 TG/sup r/ mutants/10/sup 6/ clonable cells. As with HGPRT/sup -/ mutants, XGPRT/sup -/ mutants can be selected in 6-thioguanine. AS52 (XGPRT/sup +/) and wild type CHO (HGPRT/sup +/) cell exhibit almost identical cytotoxic responses to various agents. We observed significant differences in mutation induction by UV light and ethyl methanesulfonate (EMS). Ratios of XGPRT/sup -/ to HGPRT/sup -/ mutants induced per unit dose (J/m/sup 2/ for UV light and ..mu..g/ml for EMS) are 1.4 and 0.70, respectively. Preliminary Southern blot hybridization analyses has been performed on 30 XGPRT/sup -/ AS52 mutants. A majority of spontaneous mutants have deletions ranging in size from 1 to 4 kilobases (9/19) to complete loss of gpt sequences (4/19); the remainder have no detectable (5/19) or only minor (1/19) alterations. 5/5 UV-induced and 5/6 EMS-induced mutants do not show a detectable change. Similar analyses are underway for mutations induced by x-irradiation and ICR 191 treatment.

  3. VIRAL STRATEGIES TO STUDY THE BRAIN, INCLUDING A REPLICATION-RESTRICTED SELF-AMPLIFYING DELTA-G VESICULAR STOMATIS VIRUS THAT RAPIDLY EXPRESSES TRANSGENES IN BRAIN AND CAN GENERATE A MULTICOLOR GOLGI-LIKE EXPRESSION

    PubMed Central

    van den Pol, Anthony N.; Ozduman, Koray; Wollmann, Guido; Ho, Winson; Simon, Ian; Yao, Yang; Rose, John K.; Ghosh, Prabhat

    2010-01-01

    Viruses have substantial value as vehicles to transport transgenes into neurons. Each virus has its own set of attributes for addressing neuroscience-related questions. Here we review some of the advantages and limitations of herpes, pseudorabies, rabies, adeno-associated, lentivirus, and others to study the brain. We then explore a novel recombinant vesicular stomatitis virus (dG-VSV) with the G-gene deleted and transgenes engineered into the first position of the RNA genome which replicates only in the first brain cell infected, as corroborated with ultrastructural analysis, eliminating spread of virus. Due to its ability to rapidly replicate and express multiple mRNA copies and additional templates for more copies, reporter gene expression is amplified substantially, over 500-fold in 6 hours, allowing detailed imaging of dendrites, dendritic spines, axons, and axon terminal fields within a few hours to a few days after inoculation. GFP expression is first detected within one hour of inoculation. The virus generates a Golgi-like appearance in all neuron or glia of regions of the brain tested. Whole cell patch clamp electrophysiology, calcium digital imaging with fura-2, and time-lapse digital imaging showed that neurons appeared physiologically normal after expressing viral transgenes. The virus has a wide range of species applicability, including mouse, rat, hamster, human, and drosophila cells. Using dG-VSV, we show efferent projections from the suprachiasmatic nucleus terminating in the periventricular region immediately dorsal to the nucleus. DG-VSVs with genes coding for different color reporters allow multicolor visualization of neurons wherever applied. PMID:19672982

  4. Sex-linked behavioural differences in mice expressing a human insulin transgene in the medial habenula.

    PubMed

    Douhet, P; Bertaina, V; Durkin, T; Calas, A; Destrade, C

    1997-12-01

    We previously reported that a human insulin transgene was specifically expressed in the medial habenula of the adult mouse brain, and that this expression was ascribed to the delta-168 transgene. The present study analyses the possible behavioural consequences of this insulin transgene expression using measures of food intake, spontaneous activity, emotional reactivity, learning and extinction performance of an operant task. The delta-168 transgenic mice did not differ from the C57BL/6 control mice as concerns food intake, behaviour in the open field, or emotional response in an elevated plus maze. On the other hand, measures of locomotor activity in a circular corridor revealed a significantly faster decline of spontaneous locomotor activity in male as compared to female delta-168 transgenic mice. Moreover, as compared to female transgenic mice, male transgenic mice exhibited a deficit in the rate of acquisition and an acceleration of the rate of extinction of a bar press response in a Skinner box. In contrast, the behaviour of female transgenic mice did not differ from either male or female C57BL/6 control mice. The results of the present study demonstrate that the behavioural modifications observed in delta-168 transgenic mice are sex-linked and suggest that these behavioural differences result from changes in the interaction (interface) between motivational and motor mechanisms mediated via the striato-habenulo-mesencephalic system. PMID:9475633

  5. Neuroanatomy and transgenic technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a short review that introduces recent advances of neuroanatomy and transgenic technologies. The anatomical complexity of the nervous system remains a subject of tremendous fascination among neuroscientists. In order to tackle this extraordinary complexity, powerful transgenic technologies a...

  6. Mississippi Delta

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The streamers of clouds draped over the Gulf of Mexico in this true-color MODIS image from February 27, 2002, suggest that a cold, dry wind was blowing southward over the United States and began to pick up moisture over the Gulf, causing these strips of clouds. That the clouds didn't pick up until some distance from the coastline allowed MODIS to get a perfect view of the dynamic Gulf Coast environment spanning (left to right) Texas, Louisiana, Mississippi, Alabama, and Florida's Western Panhandle. The Mississippi River runs roughly down the center of the image, and is joined in Louisiana by the Red River coming in from the northwest. Over the past 7000 years, the actual delta, where the main river channel empties into the Gulf, has wandered around what we now think of as the Louisiana coast. Considering all the sediment visible in this image, it's not hard to imagine that the river carries about 2.4 billion kilograms of sediment into the Gulf each year. Deposition of some of this sediment has been building up the current delta, called the Birdfoot Delta, for obvious reasons, for about 700 years. The coastal waters are alive with microscopic organisms called phytoplankton, which contain colorful pigments, including chlorophyll, for harvesting sunlight. Beyond the sediment plume off Louisiana, the waters are very dark, which could indicate that a large amount of chlorophyll is present, absorbing lots of sunlight and causing the water to appear dark. Farther south, the waters appear bright blue, which could be a signature of coccolithophores, which use highly reflective calcium carbonate to build scaly coverings for themselves. The brighter offshore waters could also be caused by a blue-green algae called Trichodesmium, an organism that can not only harness carbon dioxide for photosynthesis, but can also take nitrogen from the air and turn it into a form that can be used by living organisms. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  7. Mississippi Delta

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Mississippi River delta teems with sediment deposited by the river as it flows into the Gulf of Mexico in this true-color image captured by MODIS on October 15, 2001. The sediment, which is marked by brown swirls in the Gulf, provides nutrients for the bloom of phytoplankton visible as blue-green swirls off the coastline. In the high-resolution image the city of Memphis can be seen in the southwest corner of Tennessee, which is just to left of center at the top of the image. The brown coloration that encompasses Memphis and either side of the river, as flows north to south along the left side of the image, is the river's flood plain. Also visible, in the upper-right hand corner of the image is the southern end of the Appalachian Mountains.

  8. Molecular Analyses of Transgenic Plants.

    PubMed

    Trijatmiko, Kurniawan Rudi; Arines, Felichi Mae; Oliva, Norman; Slamet-Loedin, Inez Hortense; Kohli, Ajay

    2016-01-01

    One of the major challenges in plant molecular biology is to generate transgenic plants that express transgenes stably over generations. Here, we describe some routine methods to study transgene locus structure and to analyze transgene expression in plants: Southern hybridization using DIG chemiluminescent technology for characterization of transgenic locus, SYBR Green-based real-time RT-PCR to measure transgene transcript level, and protein immunoblot analysis to evaluate accumulation and stability of transgenic protein product in the target tissue. PMID:26614292

  9. Delta III—an evolutionary delta growth

    NASA Astrophysics Data System (ADS)

    Arvesen, R. J.; Simpson, J. S.

    1996-03-01

    In order to remain competitive in the future and expand the McDonnell Douglas Aerospace market share, MDA has developed an expendable launch system strategy that devices cost-effective launch systems from the Delta II with a growth vehicle configuration called Delta III. The Delta III evolves from the Delta II launch system through development of a larger payload fairing (4-meter diameter), new cryogenically propelled upper stage, new first stage fuel tank, and larger strap-on solid rocket motors. We are developing the Delta III using Integrated Product Development Teams that capitalize on the experience base that has led us to a world record breaking mission success of 49 consecutive Delta II missions. The Delta III first-launch capability is currently planned for the spring of 1998 in support of our first spacecraft customer, Hughes Space and Communications International.

  10. Transgenic control of perforin gene expression

    SciTech Connect

    Lichtenheld, M.G.; Podack, E.R.; Levy, R.B.

    1995-03-01

    Perforin is a pore-forming effector molecule of CTL and NK cells. To characterize perforin gene expression and its transcriptional control mechanisms in vivo, expression of a cell surface tag, i.e., human CD4, was driven by 5.1 kb of the murin perforin 5{prime} flanking and promoter region in transgenic mice. Six out of seven transgenic lines expressed the perforin-tag hybrid gene at low to intermediate levels, depending on the integration site. Transgene expression occurred in all cells that physiologically are able to express perforin. At the whole organ level, significant amounts of transgenic mRNA and endogenous perforin mRNA were co-expressed in the lymphoid organs, as well as in the lung, the ileum, the oviduct/uterus, and the bone marrow. At the single cell level, the perforin tag was present on NK cells and on CD8{sup +}, as well as on CD4{sup +} cells. Also targeted were Thy-1.2{sup +} {gamma}{delta} T cells, but not Thy-1.2{sup -} {gamma}{delta} T cells, B cells, nor monocytes. During thymic T cell development, transgene expression occurred in double negative (CD4{sup -}CD8{sup -}) thymocytes and was detected at all subsequent stages, but exceeded the expression levels of the endogenous gene in the thymus. In conclusion, the analyzed perforin 5{prime} flanking and promoter region contains important cis-acting sequences that restrict perforin expression to T cells and NK cells, and therefore provides a unique tool for manipulating T cell and/or Nk cell-mediated immune responses in transgenic mice. On the other hand, the normal control of perforin gene expression involves at least one additional negative control mechanism that was not mediated by the transgenic promoter and upstream region. This control restricts perforin gene expression in thymically developing T cells and in most resting peripheral T cells, but can be released upon T cell activation. 43 refs., 7 figs., 1 tab.

  11. Generation of Transgenic Mice

    PubMed Central

    Cho, Andrew; Haruyama, Naoto; Kulkarni, Ashok B.

    2009-01-01

    This unit describes detailed step-by-step protocols, reagents, and equipment required for successful generation of transgenic mice using pronuclear injection. The experimental methods and practical tips given here will help guide beginners in understanding what is required and what to avoid in these standard protocols for efficiently generating transgenic mice. PMID:19283729

  12. WEEDING IN TRANSGENES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenes promise to reduce insecticide and fungicide use, but relatively little has been done to significantly reduce herbicide use through genetic engineering. Three strategies for transgene utilization are discussed which have the potential to change this: 1) improvement of weed-specific biocon...

  13. Dipel-selected Ostrinia nubilalis larvae are not resistant to transgenic corn expressing Bacillus thuringiensis Cry1Ab

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The survival of KS-SC DipelTM-resistant and -susceptible European corn borer, Ostrinia nubilalis Hübner, was evaluated on different tissues from corn hybrids, including a non-transgenic and two transgenic corn plants (events MON810 and Bt11) expressing high doses of Bacillus thuringiensis (Bt) delta...

  14. delta-Hexachlorocyclohexane (delta-HCH)

    Integrated Risk Information System (IRIS)

    delta - Hexachlorocyclohexane ( delta - HCH ) ; CASRN 319 - 86 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Ass

  15. Tandem constructs to mitigate transgene persistence: tobacco as a model.

    PubMed

    Al-Ahmad, Hani; Galili, Shmuel; Gressel, Jonathan

    2004-03-01

    Some transgenic crops can introgress genes into other varieties of the crop, to related weeds or themselves remain as 'volunteer' weeds, potentially enhancing the invasiveness or weediness of the resulting offspring. The presently suggested mechanisms for transgene containment allow low frequency of gene release (leakage), requiring the mitigation of continued spread. Transgenic mitigation (TM), where a desired primary gene is tandemly coupled with mitigating genes that are positive or neutral to the crop but deleterious to hybrids and their progeny, was tested as a mechanism to mitigate transgene introgression. Dwarfism, which typically increases crop yield while decreasing the ability to compete, was used as a mitigator. A construct of a dominant ahasR (acetohydroxy acid synthase) gene conferring herbicide resistance in tandem with the semidominant mitigator dwarfing Delta gai (gibberellic acid-insensitive) gene was transformed into tobacco (Nicotiana tabacum). The integration and the phenotypic stability of the tandemly linked ahasR and Delta gai genomic inserts in later generations were confirmed by polymerase chain reaction. The hemizygous semidwarf imazapyr-resistant TM T1 (= BC1) transgenic plants were weak competitors when cocultivated with wild type segregants under greenhouse conditions and without using the herbicide. The competition was most intense at close spacings typical of weed offspring. Most dwarf plants interspersed with wild type died at 1-cm, > 70% at 2.5-cm and 45% at 5-cm spacing, and the dwarf survivors formed no flowers. At 10-cm spacing, where few TM plants died, only those TM plants growing at the periphery of the large cultivation containers formed flowers, after the wild type plants terminated growth. The highest reproductive TM fitness relative to the wild type was 17%. The results demonstrate the suppression of crop-weed hybrids when competing with wild type weeds, or such crops as volunteer weeds, in seasons when the selector

  16. BAC TransgeneOmics

    PubMed Central

    Poser, Ina; Sarov, Mihail; Hutchins, James R A; Hériché, Jean-Karim; Toyoda, Yusuke; Pozniakovsky, Andrei; Weigl, Daniela; Nitzsche, Anja; Hegemann, Björn; Bird, Alexander W; Pelletier, Laurence; Kittler, Ralf; Hua, Sujun; Naumann, Ronald; Augsburg, Martina; Sykora, Martina M; Hofemeister, Helmut; Zhang, Youming; Nasmyth, Kim; White, Kevin P; Dietzel, Steffen; Mechtler, Karl; Durbin, Richard; Stewart, A Francis; Peters, Jan-Michael; Buchholz, Frank; Hyman, Anthony A

    2009-01-01

    The interpretation of genome sequences requires reliable and standardized methods to assess protein function at high throughput. Here we describe a fast and reliable pipeline to study protein function in mammalian cells based on protein tagging in bacterial artificial chromosomes (BACs). The large size of the BAC transgenes ensures the presence of most, if not all, regulatory elements and results in expression that closely matches that of the endogenous gene. We show that BAC transgenes can be rapidly and reliably generated using 96-well-format recombineering. After stable transfection of these transgenes into human tissue culture cells or mouse embryonic stem cells, the localization, protein-protein and/or protein-DNA interactions of the tagged protein are studied using generic, tag-based assays. The same high-throughput approach will be generally applicable to other model systems. PMID:18391959

  17. [Oncogenesis in transgenic mice].

    PubMed

    Shvemberger, I N; Ermilov, A N

    1994-01-01

    Oncogenesis in transgenic mice is at present a model, most adequately reflecting the natural conditions of tumor development. One of more important traits of this model is that it allows to study malignant growth simultaneously at all the structure-function levels in the context of the whole organism. This paper is a review of results of a series of experiments in which the localization of tumors was dependent or independent on the tissue specificity of a promoter, as well as development of multiple tumors with the use of viral regulatory sequences in genetic constructions. It has been shown that although a transgene is expressed in most of the tissues, tumors develop in some particular tissues only. These observations are interpreted by some authors in favour of the concept of multistep cancerogenesis. In this view, of primary importance are the results of studies on oncogenesis in transgenic mice, which contradict this concept and are regarded by their authors as an evidence of the possibility of a one-step transformation of normal cell into malignant one. The analysis of the obtained material enabled us to put forward an assumption that the key role in oncogenesis is played not only by certain genetic disturbances, but also by multi-level homeostatic mechanisms. Apparently, it is just the transgenic mice with cellular or viral oncogenes in their genome that represent a more adequate model for the detection of certain molecular-biological mechanisms underlying these disturbances. Also, of much importance is abundant material accumulated by now on oncogenesis of transgenic mice which shows a possibility of the effective use of various genetic constructions with prokaryotic and eukaryotic regulatory sequences, a possibility to induce not only tumors of some particular tissues, but also multiple hyperplastic and neoplastic changes in one and the same mouse. Development of tumors in such transgenic mice can be regarded as a model of different types of cancer disease

  18. Transgenic Crops for Herbicide Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since their introduction in 1995, crops made resistant to the broad-spectrum herbicides glyphosate and glufosinate with transgenes are widely available and used in much of the world. As of 2008, over 80% of the transgenic crops grown world-wide have this transgenic trait. This technology has had m...

  19. Transgenic Farm Animals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of recombinant DNA technology has enabled scientists to isolate single genes, analyze and modify their nucleotide structure(s), make copies of these isolated genes, and insert copies of these genes into the genome of plants and animals. The transgenic technology of adding genes to li...

  20. Isolation and characterization of a Delta5-desaturase from Oblongichytrium sp.

    PubMed

    Kumon, Yasuyuki; Kamisaka, Yasushi; Tomita, Nao; Kimura, Kazuyoshi; Uemura, Hiroshi; Yokochi, Toshihiro; Yokoyama, Rinka; Honda, Daiske

    2008-08-01

    We isolated a cDNA clone with homology to known desaturase genes from Oblongichytrium sp., recently classified as a new genus of thraustochytrids (Labyrinthulomycetes), and found that it encoded Delta5-desaturase by its heterologous expression in yeast. The enzyme had higher activity toward 20:4n-3 than 20:3n-6, indicating that this Delta5-desaturase can be used in the production of n-3 polyunsaturated fatty acids in transgenic organisms. PMID:18685196

  1. 5-Azacytidine Induces Transgene Silencing by DNA Methylation in Chinese Hamster Cells

    PubMed Central

    Broday, Limor; Lee, Yong-Woo; Costa, Max

    1999-01-01

    The cytosine analog 5-azacytidine (5-AzaC) is a demethylating agent that is also known to induce mutagenesis in mammalian cells. In this study, the mutagenic potential of this drug was tested in the G10 and G12 transgenic Chinese hamster cell lines, which have a single bacterial gpt gene integrated into the genome at different sites, with its expression driven by a simian virus 40 (SV40) promoter. We show that the mutation frequencies following a 48-h exposure to different concentrations of 5-AzaC were 10 to 20 times higher than those of any of the other numerous mutagens that have been tested in the G10-G12 system. Moreover, the mutation frequencies were much higher in the G10 cell line than in the G12 cells. Detailed molecular analysis of the 6-thioguanine (6-TG)-resistant variants demonstrated that transgene silencing by de novo DNA methylation and increased chromatin condensation in the SV40 promoter was the major factor responsible for this high level of 6-TG resistance. As would be expected, exposure to 5-AzaC lowered the overall genomic DNA methylation levels, but it unexpectedly caused hypermethylation and increased chromatin condensation of the transgene in both the G10 and G12 cell lines. These results provide the first evidence that 5-AzaC may also induce transgene-specific DNA methylation, a phenomenon that can further be used for the elucidation of the mechanism that controls silencing of foreign DNA. PMID:10082586

  2. Pen Branch delta expansion

    SciTech Connect

    Nelson, E.A.; Christensen, E.J.; Mackey, H.E.; Sharitz, R.R.; Jensen, J.R.; Hodgson, M.E.

    1984-02-01

    Since 1954, cooling water discharges from K Reactor ({anti X} = 370 cfs {at} 59 C) to Pen Branch have altered vegetation and deposited sediment in the Savannah River Swamp forming the Pen Branch delta. Currently, the delta covers over 300 acres and continues to expand at a rate of about 16 acres/yr. Examination of delta expansion can provide important information on environmental impacts to wetlands exposed to elevated temperature and flow conditions. To assess the current status and predict future expansion of the Pen Branch delta, historic aerial photographs were analyzed using both basic photo interpretation and computer techniques to provide the following information: (1) past and current expansion rates; (2) location and changes of impacted areas; (3) total acreage presently affected. Delta acreage changes were then compared to historic reactor discharge temperature and flow data to see if expansion rate variations could be related to reactor operations.

  3. Delta hepatitis in Malaysia.

    PubMed

    Sinniah, M; Dimitrakakis, M; Tan, D S

    1986-06-01

    Sera from one hundred and fifty nine Malaysian individuals were screened for the prevalence of delta markers. These included 15 HBsAg positive homosexuals, 16 acute hepatitis B cases, 9 chronic hepatitis B patients, 13 healthy HBsAg carriers and 106 intravenous (i.v.) drug abusers, of whom 27 were positive for HBsAg only and the rest were anti-HBc IgG positive but HBsAg negative. The prevalence of delta markers in the homosexuals was found to be 6.7%, in the HBsAg positive drug abusers 17.8%, in acute hepatitis B cases 12.5%. No evidence of delta infection was detected in healthy HBsAg carriers, chronic hepatitis B cases and HBsAg negative i.v. drug abusers. With reference to i.v. drug abusers, the prevalence of delta markers was higher in Malays (23%) than in Chinese (7%) although the latter had a higher HBsAg carrier rate. Although the HBsAg carrier rate in the homosexuals was high, their delta prevalence rate was low as compared to drug abusers. In Malaysia, as in other non-endemic regions, hepatitis delta virus transmission appeared to occur mainly via the parenteral and sexual routes. This is the first time in Malaysia that a reservoir of delta infection has been demonstrated in certain groups of the population at high risk for hepatitis B. PMID:3787309

  4. Delta Scuti stars: Theory

    SciTech Connect

    Guzik, J.A.

    1998-03-01

    The purpose of asteroseismology is not only to derive the internal structure of individual stars from their observed oscillation frequencies, but also to test and extend one`s understanding of the physics of matter under the extremes of temperature, density, and pressure found in stellar interiors. In this review, the author hopes to point out what one can learn about the Sun by studying {delta} Scuti stars, as well as what one can learn about stars more massive or evolved than the Sun. He discusses some of the difficulties in theoretical approaches to asteroseismology for {delta} Scuti stars, using FG Vir, {delta} Scuti, and CD-24{degree} 7599 as examples.

  5. The Delta Clipper dream

    NASA Astrophysics Data System (ADS)

    Furniss, Tim

    1992-04-01

    A conceptual development status evaluation is presented for the SDIO's projected VTOL SSTOV, dubbed the 'Delta Clipper', which is envisioned as an alternative to the slowly developing NASP and the next-generation National Launch System. Delta Clipper program managers believe that the lightweight materials and structures entailed by the requisite empty/gross-weight ratio for an SSTOV are now available, precluding the airbreathing propulsion of such alternatives as HOTOL. The Delta Clipper could operate with a crew of two, or entirely unmanned. The 8-12 LH2/LOX engines employed are derived from the RL-10 engines of the Centaur launcher.

  6. Modeling river delta formation.

    PubMed

    Seybold, Hansjörg; Andrade, José S; Herrmann, Hans J

    2007-10-23

    A model to simulate the time evolution of river delta formation process is presented. It is based on the continuity equation for water and sediment flow and a phenomenological sedimentation/erosion law. Different delta types are reproduced by using different parameters and erosion rules. The structures of the calculated patterns are analyzed in space and time and compared with real data patterns. Furthermore, our model is capable of simulating the rich dynamics related to the switching of the mouth of the river delta. The simulation results are then compared with geological records for the Mississippi River. PMID:17940031

  7. Nile River Delta, Egypt

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The Nile River Delta of Egypt (30.0N, 31.0E) irrigated by the Nile River and its many distributaries, is some of the richest farm land in the world and home to some 45 million people, over half of Egypt's population. The capital city of Cairo is at the apex of the delta. Just across the river from Cairo can be seen the ancient three big pyramids and sphinx at Giza and the Suez Canal is just to the right of the delta.

  8. Nile Delta, Egypt

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The Nile Delta of Egypt (30.0N, 31.0E) irrigated by the Nile River and its many distributaries, is some of the richest farm land in the world and home to some 45 million people, over half of Egypt's population of 57 million. The capital city of Cairo is at the apex of the delta in the middle of the scene. Across the river from Cairo can be seen the three big pyramids and sphinx at Giza and the Suez Canal is just to the right of the delta.

  9. Modeling river delta formation

    PubMed Central

    Seybold, Hansjörg; Andrade, José S.; Herrmann, Hans J.

    2007-01-01

    A model to simulate the time evolution of river delta formation process is presented. It is based on the continuity equation for water and sediment flow and a phenomenological sedimentation/erosion law. Different delta types are reproduced by using different parameters and erosion rules. The structures of the calculated patterns are analyzed in space and time and compared with real data patterns. Furthermore, our model is capable of simulating the rich dynamics related to the switching of the mouth of the river delta. The simulation results are then compared with geological records for the Mississippi River. PMID:17940031

  10. Transgenics in crops

    NASA Technical Reports Server (NTRS)

    Li, Y.; Wu, Y. H.; McAvoy, R.; Duan, H.

    2001-01-01

    With rapid world population growth and declining availability of fresh water and arable land, a new technology is urgently needed to enhance agricultural productivity. Recent discoveries in the field of crop transgenics clearly demonstrate the great potential of this technology for increasing food production and improving food quality while preserving the environment for future generations. In this review, we briefly discuss some of the recent achievements in crop improvement that have been made using gene transfer technology.

  11. Population-scale laboratory studies of the effect of transgenic plants on nontarget insects.

    PubMed

    Schuler, T H; Denholm, I; Jouanin, L; Clark, S J; Clark, A J; Poppy, G M

    2001-07-01

    Studies of the effects of insect-resistant transgenic plants on beneficial insects have, to date, concentrated mainly on either small-scale "worst case scenario" laboratory experiments or on field trials. We present a laboratory method using large population cages that represent an intermediate experimental scale, allowing the study of ecological and behavioural interactions between transgenic plants, pests and their natural enemies under more controlled conditions than is possible in the field. Previous studies have also concentrated on natural enemies of lepidopteran and coleopteran target pests. However, natural enemies of other pests, which are not controlled by the transgenic plants, are also potentially exposed to the transgene product when feeding on hosts. The reduction in the use of insecticides on transgenic crops could lead to increasing problems with such nontarget pests, normally controlled by sprays, especially if there are any negative effects of the transgenic plant on their natural enemies. This study tested two lines of insect-resistant transgenic oilseed rape (Brassica napus) for side-effects on the hymenopteran parasitoid Diaeretiella rapae and its aphid host, Myzus persicae. One transgenic line expressed the delta-endotoxin Cry1Ac from Bacillus thuringiensis (Bt) and a second expressed the proteinase inhibitor oryzacystatin I (OC-I) from rice. These transgenic plant lines were developed to provide resistance to lepidopteran and coleopteran pests, respectively. No detrimental effects of the transgenic oilseed rape lines on the ability of the parasitoid to control aphid populations were observed. Adult parasitoid emergence and sex ratio were also not consistently altered on the transgenic oilseed rape lines compared with the wild-type lines. PMID:11472551

  12. Man made deltas

    PubMed Central

    Maselli, Vittorio; Trincardi, Fabio

    2013-01-01

    The review of geochronological and historical data documents that the largest southern European deltas formed almost synchronously during two short intervals of enhanced anthropic pressure on landscapes, respectively during the Roman Empire and the Little Ice Age. These growth phases, that occurred under contrasting climatic regimes, were both followed by generalized delta retreat, driven by two markedly different reasons: after the Romans, the fall of the population and new afforestation let soil erosion in river catchments return to natural background levels; since the industrial revolution, instead, flow regulation through river dams overkill a still increasing sediment production in catchment basins. In this second case, furthermore, the effect of a reduced sediment flux to the coasts is amplified by the sinking of modern deltas, due to land subsidence and sea level rise, that hampers delta outbuilding and increases the vulnerability of coastal zone to marine erosion and flooding. PMID:23722597

  13. Man made deltas.

    PubMed

    Maselli, Vittorio; Trincardi, Fabio

    2013-01-01

    The review of geochronological and historical data documents that the largest southern European deltas formed almost synchronously during two short intervals of enhanced anthropic pressure on landscapes, respectively during the Roman Empire and the Little Ice Age. These growth phases, that occurred under contrasting climatic regimes, were both followed by generalized delta retreat, driven by two markedly different reasons: after the Romans, the fall of the population and new afforestation let soil erosion in river catchments return to natural background levels; since the industrial revolution, instead, flow regulation through river dams overkill a still increasing sediment production in catchment basins. In this second case, furthermore, the effect of a reduced sediment flux to the coasts is amplified by the sinking of modern deltas, due to land subsidence and sea level rise, that hampers delta outbuilding and increases the vulnerability of coastal zone to marine erosion and flooding. PMID:23722597

  14. Federal Funding in the Delta.

    ERIC Educational Resources Information Center

    Reeder, Richard J.; Calhoun, Samuel D.

    2002-01-01

    The Lower Mississippi Delta region, especially the rural Delta, faces many economic challenges. The rural Delta has received much federal aid in basic income support and funding for human resource development, but less for community resource programs, which are important for economic development. Federal aid to the Delta is analyzed in terms of…

  15. Transgenic algae engineered for higher performance

    DOEpatents

    Unkefer, Pat J; Anderson, Penelope S; Knight, Thomas J

    2014-10-21

    The present disclosure relates to transgenic algae having increased growth characteristics, and methods of increasing growth characteristics of algae. In particular, the disclosure relates to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and a glutamine synthetase.

  16. Man made deltas?

    NASA Astrophysics Data System (ADS)

    Maselli, V.; Trincardi, F.

    2014-12-01

    During the last few millennia, southern European fluvio-deltaic systems have evolved in response to changes in the hydrological cycle, mostly driven by high-frequency climate oscillations and increasing anthropic pressure on natural landscapes. The review of geochronological and historical data documents that the bulk of the four largest northern Mediterranean and Black Sea deltas (Ebro, Rhone, Po and Danube) formed during two short and synchronous intervals during which anthropogenic land cover change was the main driver for enhanced sediment production. These two major growth phases occurred under contrasting climatic regimes and were both followed by generalized delta retreat, supporting the hypothesis of human-driven delta progradation. Delta retreat, in particular, was the consequence of reduced soil erosion for renewed afforestation after the fall of the Roman Empire, and of river dams construction that overkilled the still increasing sediment production in catchment basins since the Industrial Era. In this second case, in particular, the effect of a reduced sediment flux to the coasts is amplified by the sinking of modern deltas, due to land subsidence and sea level rise, that hampers delta outbuilding and increases the vulnerability of coastal zone to marine erosion and flooding.

  17. Cryopreservation of Xenopus transgenic lines.

    PubMed

    Buchholz, Daniel R; Fu, Liezhen; Shi, Yun-Bo

    2004-01-01

    Xenopus laevis has been widely used for molecular, cellular, and developmental studies. With the development of the sperm-mediated transgenic method, it is now possible to study gene function during vertebrate development by using this popular model. On the other hand, like other animal species, it is labor intensive, and the maintenance of transgenic lines is expensive. In this article, we investigated the possibility of using sperm-cryopreservation as a means to preserve transgenic frog lines. We demonstrated that cryopreserved sperms are viable but not fertile under our in vitro fertilization (IVF) conditions. However, by microinjecting cryopreserved sperm nuclei, we successfully regenerated a transgenic line carrying a double promoter transgene construct, where the marker gene encoding the green fluorescent protein (GFP) is driven by the gamma-crystallin gene promoter and a gene of interest, encoding a fusion protein of GFP with the matrix metalloproteinase stromelysin-3 (ST3-GFP), is driven by a heat shock-inducible promoter. We demonstrated the functional transmission of the ST3-GFP transgene by analyzing the phenotype of the F1 animals after heat-shock to induce its expression. Our method thus provides an inexpensive means to preserve transgenic frog lines and a convenient way for distribution of transgenic lines. Furthermore, the ease with which to microinject nuclei compared to the technically demanding transgenesis procedure with variable outcome should facilitate more laboratories to use transgenic Xenopus laevis for functional studies in vivo. Mol. Reprod. Dev. 67: 65-69, 2004. PMID:14648875

  18. Epigenetic silencing in transgenic plants

    PubMed Central

    Rajeevkumar, Sarma; Anunanthini, Pushpanathan; Sathishkumar, Ramalingam

    2015-01-01

    Epigenetic silencing is a natural phenomenon in which the expression of genes is regulated through modifications of DNA, RNA, or histone proteins. It is a mechanism for defending host genomes against the effects of transposable elements and viral infection, and acts as a modulator of expression of duplicated gene family members and as a silencer of transgenes. A major breakthrough in understanding the mechanism of epigenetic silencing was the discovery of silencing in transgenic tobacco plants due to the interaction between two homologous promoters. The molecular mechanism of epigenetic mechanism is highly complicated and it is not completely understood yet. Two different molecular routes have been proposed for this, that is, transcriptional gene silencing, which is associated with heavy methylation of promoter regions and blocks the transcription of transgenes, and post-transcriptional gene silencing (PTGS), the basic mechanism is degradation of the cytosolic mRNA of transgenes or endogenous genes. Undesired transgene silencing is of major concern in the transgenic technologies used in crop improvement. A complete understanding of this phenomenon will be very useful for transgenic applications, where silencing of specific genes is required. The current status of epigenetic silencing in transgenic technology is discussed and summarized in this mini-review. PMID:26442010

  19. Transgenic horticultural crops in Asia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modern biotechnology applications, including genetic engineering, are a powerful tool to complement the conventional methods of crop improvement. Asia currently has three countries cultivating biotech/transgenic crops – China, India, and the Philippines, but only China commercially grows a transgen...

  20. [Transgenic bioinsecticides inimical to parasites, but imical to environment].

    PubMed

    Kucińska, Jolanta; Lonc, Elzbieta; Rydzanicz, Katarzyna

    2003-01-01

    Identification of Bacillus thuringiensis (Bt) parasporal crystalline inclusions composed of Cry proteins (=delta-endotoxins) resulted in introduction of microbial pesticides for biological control of some parasites. Delta-endotoxins are encoded by cry genes and are active against pest and nuisance insects (mostly mosquitoes and black flies--vectors of still important infectious diseases). The recent significant progress in DNA recombination technique may overcome limitations (a short residual persistence and a narrow spectrum of activity) associated with application of Bt conventional products. An introduction of cry genes from mosquitocidal subspecies B. th. israelensis (Bti) to the aquatic microorganisms inhabiting the same water bodies as mosquito and fly larvae (Diptera), has considerably improved the toxin delivery system to target insects. However, in the first experiments, in which Bti genes were cloned in cyanobacteria (Agmenellum quadruplicatum, Synechocystis PCC6803), a low gene expression was observed. Thus, it was necessary to integrate cry genes with strong promoters or to increase the number of vector-introduced copies. To overcome the obstacles of low gene expression and regulatory restriction for recombinant organisms, Bti spore/crystal formulations were encapsulated in the aquatic protozoan, Tetrahymena pyriformis. Large numbers of crystals (180 to 240/cell) were accumulated in its food vacuoles. This system resulted also in an increase in toxin persistence from 24 to 71 h. Cloning Bti genes in B. sphaericus (which also produces mosquitocidal proteins) was another way of an increasing Bt crystal residual activity. In this case, the crystals were additionally protected by B. sphaericus exosporium. These transgenic bacteria produced large amounts of delta-endotoxins that remained under water surface longer than the wild B. sphaericus strains. Moreover, they had a broader spectrum of insecticidal activity, because B. sphaericus is toxic mostly to

  1. Delta II Mars Pathfinder

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Final preparations for lift off of the DELTA II Mars Pathfinder Rocket are shown. Activities include loading the liquid oxygen, completing the construction of the Rover, and placing the Rover into the Lander. After the countdown, important visual events include the launch of the Delta Rocket, burnout and separation of the three Solid Rocket Boosters, and the main engine cutoff. The cutoff of the main engine marks the beginning of the second stage engine. After the completion of the second stage, the third stage engine ignites and then cuts off. Once the third stage engine cuts off spacecraft separation occurs.

  2. [Transgenics without Manichaeism].

    PubMed

    Valle, S

    2000-01-01

    We live in an era characterized by the hegemony of science and technology, an era fraught with questions awaiting answers which would enable a safe and sustainable future for humankind. The development of agro-industrial processes - food products in particular - through recombinant DNA technology has enhanced the profit prospects of the few big biotechnology companies and of large-scale farmers who have access to the latest technological developments. We thus oppose a moratorium on recombinant DNA technology. Moreover, hasty statements about risk-free transgenics may be misleading in the absence of extensive safety tests. There is a pressing need for the establishment of biosafety policy in this country involving the organized civil society and every government agency responsible for monitoring such matters. There is also the need to put in place a bio-surveillance and a code of ethics regarding genetic manipulation. PMID:16680900

  3. Lessons from KIPP Delta

    ERIC Educational Resources Information Center

    Maranto, Robert; Shuls, James V.

    2011-01-01

    KIPP Delta succeeds at its stated mission, probably because of its careful attention to culture building. What distinguishes this KIPP school is thoughtful work linking the daily processes of schooling to the goals of schooling, in this case success in college. Day to day tactics reflect broader themes: having a clear mission and hiring staff who…

  4. Delta Airlines LOFT training

    NASA Technical Reports Server (NTRS)

    Whitehead, J.

    1981-01-01

    A LOFT program was developed as part of the DC-9 training program which serves as a prototype for much of Delta's other aircraft training programs. The LOFT used differs little from the ideology presented in the Advisory Circular. Difficulty and experienced concerns regarding the effectiveness of LOFT as a complete training vehicle are explored.

  5. DELTA PHASE PLUTONIUM ALLOYS

    DOEpatents

    Cramer, E.M.; Ellinger, F.H.; Land. C.C.

    1960-03-22

    Delta-phase plutonium alloys were developed suitable for use as reactor fuels. The alloys consist of from 1 to 4 at.% zinc and the balance plutonium. The alloys have good neutronic, corrosion, and fabrication characteristics snd possess good dimensional characteristics throughout an operating temperature range from 300 to 490 deg C.

  6. Using delta-front bathymetry to understand river delta progradation

    NASA Astrophysics Data System (ADS)

    Shaw, J. B.; Mohrig, D. C.

    2010-12-01

    We investigate the delta-front bathymetry of the Wax Lake Delta in Louisiana, USA; a sand rich river delta prograding quickly (~100 m/yr) into a shallow (~2.5 m) basin. The delta-front is the zone separating the bottomset from the topset of the delta. Bottomset sedimentation covers the bed evenly whereas topset sediment transport is focused by flow through distributary channels. The delta front connects these two disparate transport regimes and has a profound effect on channel-network evolution and sedimentary structure of river deltas. Predictions of delta-front topography made by models of delta progradation have rarely been compared to the bathymetry of field-scale deltas. We have mapped 60 km2 of delta front bathymetry immediately seaward of two sub-aerial distributary channels. Subaqueous channels extend up to 2 km seaward of their subaerial portions. These channels lose definition at their distal ends through a combination of channel-bed shoaling and loss of bank relief. Little bathymetric relief is observed at the fronts of the subaqueous channels, calling into question the role of channel-mouth bars in generating the bifurcations observed in this delta-channel network. Near the subaerial to subaqueous transition, steep and eroding sidewalls transition to constructional banks with gentle grades. Grab samples of bed material have been collected throughout the study area in order to detect proximal to distal fining and to constrain the shear stresses connected with delta-front sedimentation. A better understanding of sediment transport in the delta front and its affiliated patterns of erosion and deposition is essential for progress in understanding how river deltas prograde and fill their basins.

  7. The Devil's in the Delta

    ERIC Educational Resources Information Center

    Luyben, William L.

    2007-01-01

    Students frequently confuse and incorrectly apply the several "deltas" that are used in chemical engineering. The deltas come in three different flavors: "out minus in", "big minus little" and "now versus then." The first applies to a change in a stream property as the stream flows through a process. For example, the "[delta]H" in an energy…

  8. DELTAS: A new Global Delta Sustainability Initiative (Invited)

    NASA Astrophysics Data System (ADS)

    Foufoula-Georgiou, E.

    2013-12-01

    Deltas are economic and environmental hotspots, food baskets for many nations, home to a large part of the world population, and hosts of exceptional biodiversity and rich ecosystems. Deltas, being at the land-water interface, are international, regional, and local transport hubs, thus providing the basis for intense economic activities. Yet, deltas are deteriorating at an alarming rate as 'victims' of human actions (e.g. water and sediment reduction due to upstream basin development), climatic impacts (e.g. sea level rise and flooding from rivers and intense tropical storms), and local exploration (e.g. sand or aggregates, groundwater and hydrocarbon extraction). Although many efforts exist on individual deltas around the world, a comprehensive global delta sustainability initiative that promotes awareness, science integration, data and knowledge sharing, and development of decision support tools for an effective dialogue between scientists, managers and policy makers is lacking. Recently, the international scientific community proposed to establish the International Year of Deltas (IYD) to serve as the beginning of such a Global Delta Sustainability Initiative. The IYD was proposed as a year to: (1) increase awareness and attention to the value and vulnerability of deltas worldwide; (2) promote and enhance international and regional cooperation at the scientific, policy, and stakeholder level; and (3) serve as a launching pad for a 10-year committed effort to understand deltas as complex socio-ecological systems and ensure preparedness in protecting and restoring them in a rapidly changing environment. In this talk, the vision for such an international coordinated effort on delta sustainability will be presented as developed by a large number of international experts and recently funded through the Belmont Forum International Opportunities Fund. Participating countries include: U.S., France, Germany, U.K., India, Japan, Netherlands, Norway, Brazil, Bangladesh

  9. Changes in fatty acid composition in plant tissues expressing a mammalian delta9 desaturase.

    PubMed

    Moon, H; Hazebroek, J; Hildebrand, D F

    2000-05-01

    Plant tissues expressing a mammalian stearoyl-CoA delta9 desaturase were reported to accumulate delta9 hexadecenoic acid (16:1), normally very minor in most plant tissues. The transgenic plants were thoroughly analyzed for alterations of individual lipids in different subcellular sites. Western blot analysis indicated that the animal desaturase was targeted to the microsomes. The delta9 16:1 was incorporated into both the sn-1 and sn-2 positions of all the major membrane lipids tested, indicating that the endoplasmic reticulum acyltransferases do not exclude unsaturated C16 fatty acids from the sn-2 position. In addition to increases in monounsaturated and decreases in saturated fatty acids, accumulation of 16:1 was accompanied by a reduction in 18:3 in all the lipids tested except phosphatidylglycerol, and increases in 18:2 in phospholipids. Total C16 fatty acid content in the galactolipids of the transgenics was significantly higher than that in the control, but those in the phospholipids were unchanged. In transgenics, delta11 18:1 was detected in the sn-1 position of the lipids tested except phosphatidylinositol and phosphatidylserine. Introduction of the animal desaturase, controlled by a seed-specific phaseolin promoter, into soybean somatic embryo resulted in a significant reduction in saturated fatty acids. Such effects were greater in cotyledons than hypocotyl-radicles. This study demonstrated that the animal desaturase can be used to decrease the levels of saturated fatty acids in a crop plant. PMID:10907781

  10. Faster embryonic segmentation through elevated Delta-Notch signalling

    PubMed Central

    Liao, Bo-Kai; Jörg, David J.; Oates, Andrew C.

    2016-01-01

    An important step in understanding biological rhythms is the control of period. A multicellular, rhythmic patterning system termed the segmentation clock is thought to govern the sequential production of the vertebrate embryo's body segments, the somites. Several genetic loss-of-function conditions, including the Delta-Notch intercellular signalling mutants, result in slower segmentation. Here, we generate DeltaD transgenic zebrafish lines with a range of copy numbers and correspondingly increased signalling levels, and observe faster segmentation. The highest-expressing line shows an altered oscillating gene expression wave pattern and shortened segmentation period, producing embryos with more, shorter body segments. Our results reveal surprising differences in how Notch signalling strength is quantitatively interpreted in different organ systems, and suggest a role for intercellular communication in regulating the output period of the segmentation clock by altering its spatial pattern. PMID:27302627

  11. Faster embryonic segmentation through elevated Delta-Notch signalling.

    PubMed

    Liao, Bo-Kai; Jörg, David J; Oates, Andrew C

    2016-01-01

    An important step in understanding biological rhythms is the control of period. A multicellular, rhythmic patterning system termed the segmentation clock is thought to govern the sequential production of the vertebrate embryo's body segments, the somites. Several genetic loss-of-function conditions, including the Delta-Notch intercellular signalling mutants, result in slower segmentation. Here, we generate DeltaD transgenic zebrafish lines with a range of copy numbers and correspondingly increased signalling levels, and observe faster segmentation. The highest-expressing line shows an altered oscillating gene expression wave pattern and shortened segmentation period, producing embryos with more, shorter body segments. Our results reveal surprising differences in how Notch signalling strength is quantitatively interpreted in different organ systems, and suggest a role for intercellular communication in regulating the output period of the segmentation clock by altering its spatial pattern. PMID:27302627

  12. Martian deltas: Morphology and distribution

    NASA Technical Reports Server (NTRS)

    Rice, J. W., Jr.; Scott, D. H.

    1993-01-01

    Recent detailed mapping has revealed numerous examples of Martian deltas. The location and morphology of these deltas are described. Factors that contribute to delta morphology are river regime, coastal processes, structural stability, and climate. The largest delta systems on Mars are located near the mouths of Maja, Maumee, Vedra, Ma'adim, Kasei, and Brazos Valles. There are also several smaller-scale deltas emplaced near channel mouths situated in Ismenius Lacus, Memnonia, and Arabia. Delta morphology was used to reconstruct type, quantity, and sediment load size transported by the debouching channel systems. Methods initially developed for terrestrial systems were used to gain information on the relationships between Martian delta morphology, river regime, and coastal processes.

  13. Understanding pesticides in California's Delta

    USGS Publications Warehouse

    Kuivila, Kathryn M.; Orlando, James L.

    2012-01-01

    The Sacramento-San Joaquin River Delta (Delta) is the hub of California’s water system and also an important habitat for imperiled fish and wildlife. Aquatic organisms are exposed to mixtures of pesticides that flow through the maze of Delta water channels from sources including agricultural, landscape, and urban pest-control applications. While we do not know all of the effects pesticides have on the ecosystem, there is evidence that they cause some damage to organisms in the Delta. Decades of USGS research have provided a good understanding of when, where, and how pesticides enter the Delta. However, pesticide use is continually changing. New field studies and methods are needed so that scientists can analyze which pesticides are present in the Delta, and at what concentrations, enabling them to estimate exposure and ultimate effects on organisms. Continuing research will provide resource managers and stakeholders with crucial information to manage the Delta wisely.

  14. Transgenic hepatocarcinogenesis in the rat.

    PubMed Central

    Hully, J. R.; Su, Y.; Lohse, J. K.; Griep, A. E.; Sattler, C. A.; Haas, M. J.; Dragan, Y.; Peterson, J.; Neveu, M.; Pitot, H. C.

    1994-01-01

    Although transgenic hepatocarcinogenesis has been accomplished in the mouse with a number of genetic constructs targeting the oncogene to expression primarily in the liver, no example of this process has yet been developed in the rat. Because our understanding of the multistage nature of hepatocarcinogenesis is most advanced in the rat, we have developed a strain of transgenic rats carrying the promoter-enhancer sequences of the mouse albumin gene linked 5' to the simian virus-40 T antigen gene. A line of transgenic rats bearing this transgene has been developed from a single founder female. Five to six copies of the transgene, possibly in tandem, occur within the genome of the transgenic animals, which are maintained by heterozygous matings. Livers of transgenic animals are histologically normal after weaning; at 2 months of age, small foci of vacuolated cells appear in this organ. By 4 months of age, all animals exhibit focal lesions and nodules consisting primarily of small basophilic cells, many of which exhibit considerable cytoplasmic vacuolization. Mating of animals each bearing the transgene results in rats with a demyelinating condition that develops acutely in pregnant females and more chronically in males. Ultrastructural studies of these cells indicate that the vacuoles contain substantial amounts of glycogen, with the cells resembling hepatoblasts. Malignant neoplasms with both a glandular and a hepatoblastoma/hepatocellular carcinoma pattern arise from the nodules. Enzyme and immunohistochemical studies of all lesions reveal many similarities in gene expression to comparable lesions in rats subjected to chemically induced hepatocarcinogenesis, with certain exceptions. The placental form of glutathione-S-transferase is absent from all lesions in the transgenic animal, as is the expression of connexin 32. A significant number of lesions express serum albumin, and many, but not all, exhibit the T antigen. Lesions expressing the T antigen also contain

  15. Mississippi River Delta

    NASA Technical Reports Server (NTRS)

    2002-01-01

    As the Mississippi River enters the Gulf of Mexico, it loses energy and dumps its load of sediment that it has carried on its journey through the mid continent. This pile of sediment, or mud, accumulates over the years building up the delta front. As one part of the delta becomes clogged with sediment, the delta front will migrate in search of new areas to grow. The area shown on this image is the currently active delta front of the Mississippi. The migratory nature of the delta forms natural traps for oil. Most of the land in the image consists of mud flats and marsh lands. There is little human settlement in this area due to the instability of the sediments. The main shipping channel of the Mississippi River is the broad stripe running northwest to southeast.

    This image was acquired on May 24, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18,1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping

  16. Natural processes in delta restoration: application to the Mississippi Delta.

    PubMed

    Paola, Chris; Twilley, Robert R; Edmonds, Douglas A; Kim, Wonsuck; Mohrig, David; Parker, Gary; Viparelli, Enrica; Voller, Vaughan R

    2011-01-01

    Restoration of river deltas involves diverting sediment and water from major channels into adjoining drowned areas, where the sediment can build new land and provide a platform for regenerating wetland ecosystems. Except for local engineered structures at the points of diversion, restoration mainly relies on natural delta-building processes. Present understanding of such processes is sufficient to provide a basis for determining the feasibility of restoration projects through quantitative estimates of land-building rates and sustainable wetland area under different scenarios of sediment supply, subsidence, and sea-level rise. We are not yet to the point of being able to predict the evolution of a restored delta in detail. Predictions of delta evolution are based on field studies of active deltas, deltas in mine-tailings ponds, experimental deltas, and countless natural experiments contained in the stratigraphic record. These studies provide input for a variety of mechanistic delta models, ranging from radially averaged formulations to more detailed models that can resolve channels, topography, and ecosystem processes. Especially exciting areas for future research include understanding the mechanisms by which deltaic channel networks self-organize, grow, and distribute sediment and nutrients over the delta surface and coupling these to ecosystem processes, especially the interplay of topography, network geometry, and ecosystem dynamics. PMID:21329199

  17. Modification of fatty acid composition in tomato (Lycopersicon esculentum) by expression of a borage delta6-desaturase.

    PubMed

    Cook, David; Grierson, Don; Jones, Craigh; Wallace, Andrew; West, Gill; Tucker, Greg

    2002-06-01

    The improvement of nutritional quality is one potential application for the genetic modification of plants. One possible target for such manipulation is the modification of fatty acid metabolism. In this work, expression of a borage delta6-desaturase cDNA in tomato (Lycopersicon esculentum L.) has been shown to produce gamma-linolenic acid (GLA; 18:83 delta6,9,12) and octadecatetraenoic acid (OTA; 18:4 delta6,9,12,15) in transgenic leaf and fruit tissue. This genetic modification has also, unexpectedly, resulted in a reduction in the percentage of linoleic acid (LA 18:2 delta9,12) and a concomitant increase in the percentage of alpha-linolenic acid (ALA; 18:3 delta9,12,15) in fruit tissue. These changes in fatty acid composition are thought to be beneficial for human health. PMID:12059112

  18. Pioneer Launch on Delta Vehicle

    NASA Technical Reports Server (NTRS)

    1969-01-01

    NASA launches the last in the series of interplanetary Pioneer spacecraft, Pioneer 10 from Cape Kennedy, Florida. The long-tank Delta launch vehicle placed the spacecraft in a solar orbit along the path of Earth's orbit. The spacecraft then passed inside and outside Earth's orbit, alternately speeding up and slowing down relative to Earth. The Delta launch vehicle family started development in 1959. The Delta was composed of parts from the Thor, an intermediate-range ballistic missile, as its first stage, and the Vanguard as its second. The first Delta was launched from Cape Canaveral on May 13, 1960 and was powerful enough to deliver a 100-pound spacecraft into geostationary transfer orbit. Delta has been used to launch civil, commercial, and military satellites into orbit. For more information about Delta, please see Chapter 3 in Roger Launius and Dennis Jenkins' book To Reach the High Frontier published by The University Press of Kentucky in 2002.

  19. Delta in Eberswalde

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This HiRISE image covers a portion of a delta that partially fills Eberswalde crater in Margaritifer Sinus. The delta was first recognized and mapped using MOC images that revealed various features whose presence required sustained flow and deposition into a lake that once occupied the crater. The HiRISE image resolves meter-scale features that record the migration of channels and delta distributaries as the delta grew over time. Differences in grain-size of sediments within the environments on the delta enable differential erosion of the deposits. As a result, coarser channel deposits are slightly more resistant and stand in relief relative to finer-grained over-bank and more easily eroded distal delta deposits. Close examination of the relict channel deposits confirms the presence of some meter-size blocks that were likely too coarse to have been transported by water flowing within the channels. These blocks may be formed of the sand and gravel that more likely moved along the channels that was lithified and eroded. Numerous meter-scale polygonal structures are common on many surfaces, but mostly those associated with more quiescent depositional environments removed from the channels. The polygons could be the result of deposition of fine-grained sediments that were either exposed and desiccated (dried out), rich in clays that shrunk when the water was removed, turned into rock and then fractured and eroded, or some combination of these processes.

    Image PSP_001336_1560 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on November 8, 2006. The complete image is centered at -23.8 degrees latitude, 326.4 degrees East longitude. The range to the target site was 256.3 km (160.2 miles). At this distance the image scale is 25.6 cm/pixel (with 1 x 1 binning) so objects 77 cm across are resolved. The image shown here has been map-projected to 25 cm/pixel and north is up. The image was

  20. Lift force of delta wings

    SciTech Connect

    Lee, M.; Ho, Chihming )

    1990-09-01

    On a delta wing, the separation vortices can be stationary due to the balance of the vorticity surface flux and the axial convection along the swept leading edge. These stationary vortices keep the wing from losing lift. A highly swept delta wing reaches the maximum lift at an angle of attack of about 40, which is more than twice as high as that of a two-dimensional airfoil. In this paper, the experimental results of lift forces for delta wings are reviewed from the perspective of fundamental vorticity balance. The effects of different operational and geometrical parameters on the performance of delta wings are surveyed.

  1. [Transgenic animals and animal welfare

    PubMed

    Reinhardt, Christoph

    1998-01-01

    Under the pressure of a public vote in Switzerland (7 June 1998) on an initiative to ban the production, use and patenting of transgenic animals, their value for biomedical research and development is intensely debated. In addition, the Swiss legislation has adopted (1992) a constitutional obligation to "take into account the dignity of creatures". The term "dignity of creatures", however, can be interpreted in anthropocentric or biocentric ways. The government has now formulated the legal implications of this term for transgenic animals and plants in various laws including the animal and environmental protection laws. This paper gives arguments for a fair evaluation of trangenic animals from an animal welfare point of view where not only the costs of animal suffering must be considered but also the probability of potential benefit for man. A self-confident research community should allow such an evaluation procedure even in view of an outcome which could ban many uses of transgenic animals PMID:11208266

  2. Cryopreservation of transgenic mouse lines.

    PubMed

    Pomeroy, K O

    1993-01-01

    A transgenic animal represents an enormous investment in time and money. Animals can be destroyed through disease, fire, malfuncnons in the control of the environment, negligence, sabotage, or accidental disposal. Researchers can protect valuable transgenic lines from accrdental destruction by "banking" them in liquid nitrogen. Cryopreservation can also reduce animal costs by decreasing the number of live animals investigators must maintain. Often, when one is trying to produce a transgenic animal, some lines will be derived that may not initially appear interesting. These animals can be stored in liquid nitrogen for future recovery and study. The maintenance of just one line of mice, say 25 mice at 15 cents/d, can cost over $1000 (US) in a single year. PMID:21390665

  3. Holden Crater Delta

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA03694 Holden Crater Delta

    This fan-shaped delta deposit is located in Holden Crater.

    Image information: VIS instrument. Latitude -27.3N, Longitude 324.5E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  4. Shanghai Delta Complex

    SciTech Connect

    Hart, R.E.; Hoffman, P.F.; Parker, R.W.

    1988-01-01

    The upper Eocene Yegua Formation expands dramatically across a regional system of growth faults into an area generally 12-15 km wide, extending at least from the western edge of the Houston sale dome basin to the San Marcos arch. Within this area, the expanded Yegua trend has yielded, since 1982, at least seven noteworthy discoveries: Toro Grande and Lost Bridge fields in Jackson County, and Black Owl, Shanghai, Shanghai East, El Campo, and Phase Four fields in Wharton County. During each of several postulated Yegua sea level drops, this flexure became a focal point for deltaic deposition of excellent reservoir-quality sands. Shanghai, Shanghai East, and El Campo fields are located within what the writers have labeled the ''Shanghai delta complex.'' Integration of seismic and well data in this vicinity shows a marked increase in the expansion indices of growth faults, and moderately thick progradational sand sequences have accumulated immediately downthrow. This structural-stratigraphic pattern, as well as internal bedding characteristics and other lithologic data observed, is believed typical of deltas deposited along the Yegua shelf margin.

  5. Thermostatted delta f

    SciTech Connect

    Krommes, J.A.

    2000-01-18

    The delta f simulation method is revisited. Statistical coarse-graining is used to rigorously derive the equation for the fluctuation delta f in the particle distribution. It is argued that completely collisionless simulation is incompatible with the achievement of true statistically steady states with nonzero turbulent fluxes because the variance of the particle weights w grows with time. To ensure such steady states, it is shown that for dynamically collisionless situations a generalized thermostat or W-stat may be used in lieu of a full collision operator to absorb the flow of entropy to unresolved fine scales in velocity space. The simplest W-stat can be implemented as a self-consistently determined, time-dependent damping applied to w. A precise kinematic analogy to thermostatted nonequilibrium molecular dynamics (NEMD) is pointed out, and the justification of W-stats for simulations of turbulence is discussed. An extrapolation procedure is proposed such that the long-time, steady-state, collisionless flux can be deduced from several short W-statted runs with large effective collisionality, and a numerical demonstration is given.

  6. How To Produce and Characterize Transgenic Plants.

    ERIC Educational Resources Information Center

    Savka, Michael A.; Wang, Shu-Yi; Wilson, Mark

    2002-01-01

    Explains the process of establishing transgenic plants which is a very important tool in plant biology and modern agriculture. Produces transgenic plants with the ability to synthesize opines. (Contains 17 references.) (YDS)

  7. [Current status and industrialization of transgenic tomatoes].

    PubMed

    Wang, Ao-Xue; Chen, Xiu-Ling

    2011-09-01

    In this review, the progress in transgenic tomato research, including disease and insect resistance, herbicide resistance, stress tolerance, long-term storage, quality improvement, and male sterility, were described. The recent researches on producing heterologous proteins using transgenic tomatoes were also reviewed. Furthermore, the industrialization status and problems of transgenic tomatoes were analyzed and the prospects of both research and industrialization in transgenic tomatoes were discussed. PMID:21951797

  8. TRANSGENIC FISH: In Genomics and Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fish into which foreign DNA is artificially introduced and integrated into their genome are called transgenic fish. Since the development of the first transgenic fish in 1985, techniques to produce transgenic fish have improved tremendously, resulting in the production of genetically modified (GM)...

  9. Delta Electroproduction in 12-C

    SciTech Connect

    Steven McLauchlan

    2003-01-31

    The Delta-nucleus potential is a crucial element in the understanding of the nuclear system. Previous electroexcitation measurements in the delta region reported a Q2 dependence of the delta mass indicating that this potential is dependent on the momentum of the delta. Such a dependence is not observed for protons and neutrons in the nuclear medium. This thesis presents the experimental study of the electroexcitation of the delta resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4(pie) acceptance detector CLAS that enables the detection of the full reaction final state. Inclusive, semi inclusive, and exclusive cross sections were measured with an incident electron beam energy of 1.162GeV over the Q2 range 0.175-0.475 (GeV/c)2. A Q2 dependence of the delta mass was only observed in the exclusive measurements indicating that the delta-nucleus potential is affected by the momentum of the delta.

  10. Human health and transgenic crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Under the joint auspices of the Agrochemical and the Agricultural and Food Chemistry Divisions of the American Chemical Society, we organized a short symposium on “Human Health and Transgenic Crops” at the 244th ACS national meeting, held August 19-23, 2012 in Philadelphia, PA, to examine an array o...

  11. Colorado River Delta

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Colorado River ends its 2330 km journey in the Gulf of Mexico in Baja California. The heavy use of the river as an irrigation source for the Imperial Valley has dessicated the lower course of the river in Mexico such that it no longer consistently reaches the sea. Prior to the mid 20th century, the Colorado River Delta provided a rich estuarine marshland that is now essentially desiccated, but nonetheless is an important ecological resource.

    The image was acquired May 29, 2006, covers an area of 44.3 x 57.5 km, and is located at 32.1 degrees north latitude, 115.1 degrees west longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  12. Mackenzie River Delta, Canada

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The Mackenzie River in the Northwest Territories, Canada, with its headstreams the Peace and Finley, is the longest river in North America at 4241 km, and drains an area of 1,805,000 square km. The large marshy delta provides habitat for migrating Snow Geese, Tundra Swans, Brant, and other waterfowl. The estuary is a calving area for Beluga whales. The Mackenzie (previously the Disappointment River) was named after Alexander Mackenzie who travelled the river while trying to reach the Pacific in 1789.

    The image was acquired on August 4, 2005, covers an area of 55.8 x 55.8 km, and is located at 68.6 degrees north latitude, 134.7 degrees west longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  13. Artificial delta growth

    NASA Astrophysics Data System (ADS)

    Mikeš, Daniel

    2010-05-01

    A deltaic sedimentary system has a point source; sediment is carried over the delta plain by distributary channels away from the point source and deposited at the delta front by distributary mouth bars. The established methods to describe such a sedimentary system are "bedding analysis", "facies analysis", and "basin analysis". We shall call the ambient conditions "input" and the rock record "output". There exist a number of methods to deduce input from output, e.g. "Sequence stratigraphy" (a.o. Vail et al. 1977, Catuneanu et al. 2009), "Shoreline trajectory" (a.o. Helland-Hansen & Martinsen 1996, Helland-Hansen & Hampson 2009) on the one hand and the complex use of established techniques on the other (a.o. Miall & Miall 2001, Miall & Miall 2002). None of these deductive methods seems to be sufficient. I claim that the common errors in all these attempts are the following: (1) a sedimentary system is four-dimensional (3+1) and a lesser dimensional analysis is insufficient; (2) a sedimentary system is complex and any empirical/deductive analysis is non-unique. The proper approach to the problem is therefore the theoretical/inductive analysis. To that end we performed six scenarios of a scaled version of a passive margin delta in a flume tank. The scenarios have identical stepwise tectonic subsidence and semi-cyclic sealevel, but different supply curves, i.e. supply is: constant, highly-frequent, proportional to sealevel, inversely proportional to sealevel, lagging to sealevel, ahead of sealevel. The preliminary results are indicative. Lobe-switching occurs frequently and hence locally sedimentation occurs shortly and hiatuses are substantial; therefore events in 2D (+1) cross-sections don't correlate temporally. The number of sedimentary cycles disequals the number of sealevel cycles. Lobe-switching and stepwise tectonic subsidence cause onlap/transgression. Erosional unconformities are local diachronous events, whereas maximum flooding surfaces are regional

  14. Delta spots and great flares

    NASA Technical Reports Server (NTRS)

    Zirin, Harold; Liggett, Margaret A.

    1987-01-01

    The development of delta spots and the great flares they produce are reviewed based on 18 years of observations. Delta groups are found to develop in three ways: (1) by the eruption of a single complex active region formed below the surface; (2) by the eruption of large satellite spots near a large older spot; and (3) by the collision of spots of opposite polarity from different dipoles. It is shown that the present sample of 21 delta spots never separate once they lock together, and that the driving force for the shear is spot motion. Indicators for the prediction of the occurrence of great flares are identified.

  15. Striatal cell type-specific overexpression of DeltaFosB enhances incentive for cocaine.

    PubMed

    Colby, Christina R; Whisler, Kim; Steffen, Cathy; Nestler, Eric J; Self, David W

    2003-03-15

    The transcription factor DeltaFosB accumulates in substance P-dynorphin-containing striatal neurons with repeated cocaine use. Here, we show that inducible transgenic DeltaFosB overexpression in this same striatal cell type facilitates acquisition of cocaine self-administration at low-threshold doses, consistent with increased sensitivity to the pharmacological effects of the drug. Importantly, DeltaFosB also enhances the degree of effort mice will exert to maintain self-administration of higher doses on a progressive ratio schedule of reinforcement, whereas levels of cocaine intake are not altered on less demanding fixed-ratio schedules. Acquisition and extinction of behavior reinforced by food pellets is not altered in DeltaFosB-overexpressing mice, indicating that DeltaFosB does not alter the capacity to learn an instrumental response or cause response perseveration in the absence of reinforcement. These data suggest that accumulation of DeltaFosB contributes to drug addiction by increasing the incentive properties of cocaine, an effect that could increase the risk for relapse long after cocaine use ceases. PMID:12657709

  16. Transgenic Arabidopsis Gene Expression System

    NASA Technical Reports Server (NTRS)

    Ferl, Robert; Paul, Anna-Lisa

    2009-01-01

    The Transgenic Arabidopsis Gene Expression System (TAGES) investigation is one in a pair of investigations that use the Advanced Biological Research System (ABRS) facility. TAGES uses Arabidopsis thaliana, thale cress, with sensor promoter-reporter gene constructs that render the plants as biomonitors (an organism used to determine the quality of the surrounding environment) of their environment using real-time nondestructive Green Fluorescent Protein (GFP) imagery and traditional postflight analyses.

  17. Delta-9 desaturase from sharpshooters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomic analyses of several leafhoppers identified the first leafhopper delta-9 desaturase. Identification of important gene transcripts within insect pests permits them to be targeted with RNA interference, RNAi, strategies. The glassy-winged sharpshooter, GWSS (Hemiptera: Cicadellidae; Homalodis...

  18. Transgenic mouse offspring generated by ROSI.

    PubMed

    Moreira, Pedro; Pérez-Cerezales, Serafín; Laguna, Ricardo; Fernández-Gonzalez, Raúl; Sanjuanbenito, Belén Pintado; Gutiérrez-Adán, Alfonso

    2016-01-01

    The production of transgenic animals is an important tool for experimental and applied biology. Over the years, many approaches for the production of transgenic animals have been tried, including pronuclear microinjection, sperm-mediated gene transfer, transfection of male germ cells, somatic cell nuclear transfer and the use of lentiviral vectors. In the present study, we developed a new transgene delivery approach, and we report for the first time the production of transgenic animals by co-injection of DNA and round spermatid nuclei into non-fertilized mouse oocytes (ROSI). The transgene used was a construct containing the human CMV immediate early promoter and the enhanced GFP gene. With this procedure, 12% of the live offspring we obtained carried the transgene. This efficiency of transgenic production by ROSI was similar to the efficiency by pronuclear injection or intracytoplasmic injection of male gamete nuclei (ICSI). However, ICSI required fewer embryos to produce the same number of transgenic animals. The expression of Egfp mRNA and fluorescence of EGFP were found in the majority of the organs examined in 4 transgenic lines generated by ROSI. Tissue morphology and transgene expression were not distinguishable between transgenic animals produced by ROSI or pronuclear injection. Furthermore, our results are of particular interest because they indicate that the transgene incorporation mediated by intracytoplasmic injection of male gamete nuclei is not an exclusive property of mature sperm cell nuclei with compact chromatin but it can be accomplished with immature sperm cell nuclei with decondensed chromatin as well. The present study also provides alternative procedures for transgene delivery into embryos or reconstituted oocytes. PMID:26498042

  19. Supersonic aerodynamics of delta wings

    NASA Technical Reports Server (NTRS)

    Wood, Richard M.

    1988-01-01

    Through the empirical correlation of experimental data and theoretical analysis, a set of graphs has been developed which summarize the inviscid aerodynamics of delta wings at supersonic speeds. The various graphs which detail the aerodynamic performance of delta wings at both zero-lift and lifting conditions were then employed to define a preliminary wing design approach in which both the low-lift and high-lift design criteria were combined to define a feasible design space.

  20. Expression of a coriander desaturase results in petroselinic acid production in transgenic tobacco

    SciTech Connect

    Cahoon, E.B.; Shanklin, J.; Ohlrogge, J.B. )

    1992-12-01

    Little is known about the metabolic origin of petroselinic acid (18:1[Delta][sup 6cis]), the principal fatty acid of the seed oil of most Umbelliferae, Araliaceae, and Garryaceae species. To examine the possibility that petroselinic acid is the product of an acyl-acyl carrier protein (ACP) desaturase, Western blots of coriander and other Umbelliferae seed extracts were probed with antibodies against the [Delta][sup 9]-stearoyl-ACP desaturase of avocado. In these extracts, proteins of 39 and 36 kDa were detected. Of these, only the 36-kDa peptide was specific to tissues which synthesize petroselinic acid. A cDNA encoding the 36-kDa peptide was isolated from a coriander endosperm cDNA library, placed under control of the cauliflower mosaic virus 35S promoter, and introduced into tobacco by Agrobacterium tumefaciens-mediated transformation. Expression of this cDNA in transgenic tobacco callus was accompanied by the accumulation of petroselinic acid and [Delta][sup 4]-hexadecenoic acid, both of which were absent from control callus. These results demonstrate the involvement of a 36-kDa putative acyl-ACP desaturase in the biosynthetic pathway of petroselinic acid and the ability to produce fatty acids of unusual structure in transgenic plants by the expression of the gene for this desaturase. 27 refs., 5 figs.

  1. Expression of a coriander desaturase results in petroselinic acid production in transgenic tobacco.

    PubMed Central

    Cahoon, E B; Shanklin, J; Ohlrogge, J B

    1992-01-01

    Little is known about the metabolic origin of petroselinic acid (18:1 delta 6cis), the principal fatty acid of the seed oil of most Umbelliferae, Araliaceae, and Garryaceae species. To examine the possibility that petroselinic acid is the product of an acyl-acyl carrier protein (ACP) desaturase, Western blots of coriander and other Umbelliferae seed extracts were probed with antibodies against the delta 9-stearoyl-ACP desaturase of avocado. In these extracts, proteins of 39 and 36 kDa were detected. Of these, only the 36-kDa peptide was specific to tissues which synthesize petroselinic acid. A cDNA encoding the 36-kDa peptide was isolated from a coriander endosperm cDNA library, placed under control of the cauliflower mosaic virus 35S promoter, and introduced into tobacco by Agrobacterium tumefaciens-mediated transformation. Expression of this cDNA in transgenic tobacco callus was accompanied by the accumulation of petroselinic acid and delta 4-hexadecenoic acid, both of which were absent from control callus. These results demonstrate the involvement of a 36-kDa putative acyl-ACP desaturase in the biosynthetic pathway of petroselinic acid and the ability to produce fatty acids of unusual structure in transgenic plants by the expression of the gene for this desaturase. Images PMID:1454797

  2. Composition of transgenic soybean seeds with higher γ-linolenic acid content is equivalent to that of conventional control.

    PubMed

    Qin, Fengyun; Kang, Linzhi; Guo, Liqiong; Lin, Junfang; Song, Jingshen; Zhao, Yinhua

    2012-03-01

    γ-Linolenic acid (GLA) has been used as a general nutraceutical for pharmacologic applications, particularly in the treatment of skin conditions such as eczema. Four transgenic soybean lines that produce GLA at high yields (4.21% of total fatty acids, up to 1002-fold) were generated through the stable insertion of the Delta-6-fatty acid desaturase gene isolated from Borago officinalis into the genome of a conventional soybean cultivar. As part of the safety assessment of genetically engineered crops, the transgenic soybean seeds were compared with their parental soybean seeds (nontransgenic) by applying the principle of substantial equivalence. Compositional analyses were conducted by measuring the fatty acids, proximate analysis (moisture, crude protein, crude fat, carbohydrates, TDF, and ash contents), amino acids, lectins, and trypsin inhibitor activity. The present results showed that the specific transgenic cultivar studied was similar to the conventional control. PMID:22324875

  3. A built-in strategy for containment of transgenic plants: creation of selectively terminable transgenic rice.

    PubMed

    Lin, Chaoyang; Fang, Jun; Xu, Xiaoli; Zhao, Te; Cheng, Jiaan; Tu, Juming; Ye, Gongyin; Shen, Zhicheng

    2008-01-01

    Plant transgenic technology has been widely utilized for engineering crops for trait improvements and for production of high value proteins such as pharmaceuticals. However, the unintended spreading of commercial transgenic crops by pollination and seed dispersal is a major concern for environmental and food safety. Simple and reliable containment strategies for transgenes are highly desirable. Here we report a novel method for creating selectively terminable transgenic rice. In this method, the gene(s) of interest is tagged with a RNA interference cassette, which specifically suppresses the expression of the bentazon detoxification enzyme CYP81A6 and thus renders transgenic rice to be sensitive to bentazon, a herbicide used for rice weed control. We generated transgenic rice plants by this method using a new glyphosate resistant 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene from Pesudomonas putida as the gene of interest, and demonstrated that these transgenic rice plants were highly sensitive to bentazon but tolerant to glyphosate, which is exactly the opposite of conventional rice. Field trial of these transgenic rice plants further confirmed that they can be selectively killed at 100% by one spray of bentazon at a regular dose used for conventional rice weed control. Furthermore, we found that the terminable transgenic rice created in this study shows no difference in growth, development and yield compared to its non-transgenic control. Therefore, this method of creating transgenic rice constitutes a novel strategy of transgene containment, which appears simple, reliable and inexpensive for implementation. PMID:18350155

  4. A Built-In Strategy for Containment of Transgenic Plants: Creation of Selectively Terminable Transgenic Rice

    PubMed Central

    Zhao, Te; Cheng, Jiaan; Tu, Juming; Ye, Gongyin; Shen, Zhicheng

    2008-01-01

    Plant transgenic technology has been widely utilized for engineering crops for trait improvements and for production of high value proteins such as pharmaceuticals. However, the unintended spreading of commercial transgenic crops by pollination and seed dispersal is a major concern for environmental and food safety. Simple and reliable containment strategies for transgenes are highly desirable. Here we report a novel method for creating selectively terminable transgenic rice. In this method, the gene(s) of interest is tagged with a RNA interference cassette, which specifically suppresses the expression of the bentazon detoxification enzyme CYP81A6 and thus renders transgenic rice to be sensitive to bentazon, a herbicide used for rice weed control. We generated transgenic rice plants by this method using a new glyphosate resistant 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene from Pesudomonas putida as the gene of interest, and demonstrated that these transgenic rice plants were highly sensitive to bentazon but tolerant to glyphosate, which is exactly the opposite of conventional rice. Field trial of these transgenic rice plants further confirmed that they can be selectively killed at 100% by one spray of bentazon at a regular dose used for conventional rice weed control. Furthermore, we found that the terminable transgenic rice created in this study shows no difference in growth, development and yield compared to its non-transgenic control. Therefore, this method of creating transgenic rice constitutes a novel strategy of transgene containment, which appears simple, reliable and inexpensive for implementation. PMID:18350155

  5. The DELTA Synchrotron Light Interferometer

    SciTech Connect

    Berges, U.

    2004-05-12

    Synchrotron radiation sources like DELTA, the Dortmund Electron Accelerator, a third generation synchrotron light source, need an optical monitoring system to measure the beam size at different points of the ring with high resolution and accuracy. These measurements also allow an investigation of the emittance of the storage ring, an important working parameter for the efficiency of working beamlines with experiments using the synchrotron radiation. The resolution limits of the different types of optical synchrotron light monitors at DELTA are investigated. The minimum measurable beamsize with the normal synchrotron light monitor using visible light at DELTA is about 80 {mu}m. Due to this a synchrotron light interferometer was built up and tested at DELTA. The interferometer uses the same beamline in the visible range. The minimum measurable beamsize is with about 8 {mu}m one order of magnitude smaller. This resolution is sufficient for the expected small vertical beamsizes at DELTA. The electron beamsize and emittance were measured with both systems at different electron beam energies of the storage ring. The theoretical values of the present optics are smaller than the measured emittance. So possible reasons for beam movements are investigated.

  6. Transgenic Models in Retinoblastoma Research.

    PubMed

    Nair, Rohini M; Vemuganti, Geeta K

    2015-04-01

    Understanding the mechanism of retinoblastoma (Rb) tumor initiation, development, progression and metastasis in vivo mandates the use of animal models that mimic this intraocular tumor in its genetic, anatomic, histologic and ultrastructural features. An early setback for developing mouse Rb models was that Rb mutations did not cause tumorigenesis in murine retinas. Subsequently, the discovery that the p107 protein takes over the role of pRb in mice led to the development of several animal models that phenotypically and histologically resemble the human form. This paper summarizes the transgenic models that have been developed over the last three decades. PMID:27171579

  7. Transgenic Models in Retinoblastoma Research

    PubMed Central

    Nair, Rohini M.; Vemuganti, Geeta K.

    2015-01-01

    Understanding the mechanism of retinoblastoma (Rb) tumor initiation, development, progression and metastasis in vivo mandates the use of animal models that mimic this intraocular tumor in its genetic, anatomic, histologic and ultrastructural features. An early setback for developing mouse Rb models was that Rb mutations did not cause tumorigenesis in murine retinas. Subsequently, the discovery that the p107 protein takes over the role of pRb in mice led to the development of several animal models that phenotypically and histologically resemble the human form. This paper summarizes the transgenic models that have been developed over the last three decades. PMID:27171579

  8. An Expanded Notch-Delta Model Exhibiting Long-Range Patterning and Incorporating MicroRNA Regulation

    PubMed Central

    Chen, Jerry S.; Gumbayan, Abygail M.; Zeller, Robert W.; Mahaffy, Joseph M.

    2014-01-01

    Notch-Delta signaling is a fundamental cell-cell communication mechanism that governs the differentiation of many cell types. Most existing mathematical models of Notch-Delta signaling are based on a feedback loop between Notch and Delta leading to lateral inhibition of neighboring cells. These models result in a checkerboard spatial pattern whereby adjacent cells express opposing levels of Notch and Delta, leading to alternate cell fates. However, a growing body of biological evidence suggests that Notch-Delta signaling produces other patterns that are not checkerboard, and therefore a new model is needed. Here, we present an expanded Notch-Delta model that builds upon previous models, adding a local Notch activity gradient, which affects long-range patterning, and the activity of a regulatory microRNA. This model is motivated by our experiments in the ascidian Ciona intestinalis showing that the peripheral sensory neurons, whose specification is in part regulated by the coordinate activity of Notch-Delta signaling and the microRNA miR-124, exhibit a sparse spatial pattern whereby consecutive neurons may be spaced over a dozen cells apart. We perform rigorous stability and bifurcation analyses, and demonstrate that our model is able to accurately explain and reproduce the neuronal pattern in Ciona. Using Monte Carlo simulations of our model along with miR-124 transgene over-expression assays, we demonstrate that the activity of miR-124 can be incorporated into the Notch decay rate parameter of our model. Finally, we motivate the general applicability of our model to Notch-Delta signaling in other animals by providing evidence that microRNAs regulate Notch-Delta signaling in analogous cell types in other organisms, and by discussing evidence in other organisms of sparse spatial patterns in tissues where Notch-Delta signaling is active. PMID:24945987

  9. Transgenic Papaya: Development, Release, Impact, and Challenges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although the technology for developing virus-resistant transgenic plants through the use of the coat protein of a virus was unveiled twenty years ago, it is surprising to note that only a three virus-resistant plants (squash, potato, and papaya) have been commercialized in the U.S. The transgenic p...

  10. Transgenic Biofuel Feedstocks and Strategies for Biocontainment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are several reasons to believe that transgenic plant feedstocks will be required to realize the full economic and environmental benefits of cellulosic and other biofuels. Much of the commercialization potential for the use of transgenic plant cellulosic feedstocks may be impacted by regulatio...

  11. 2008 FHB Analysis of Transgenic Barley Lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenic lines have been developed with the goal of reducing FHB and DON in barley. Replicated field trials for FHB reaction of 48 Conlon transgenic lines were conducted in 2008 in Langdon, ND and Rosemount, MN. The Langdon trials consisted of three replicates in hill plots in an inoculated misted...

  12. Accumulation of nickel in transgenic tobacco

    NASA Astrophysics Data System (ADS)

    Sidik, Nik Marzuki; Othman, Noor Farhan

    2013-11-01

    The accumulation of heavy metal Ni in the roots and leaves of four T1 transgenic lines of tobacco (T(1)20E, T(1)24C, T(1)18B1 and T(1)20B) expressing eiMT1 from E.indica was assessed. The aim of the study was to investigate the level of Ni accumulation in the leaves and roots of each transgenic lines and to evaluate the eligibility of the plants to be classified as a phytoremediation agent. All of the transgenic lines showed different ability in accumulating different metals and has translocation factor (TF) less than 1 (TF<1) at all levels of metal treatment. Among the 4 transgenic lines, transgenic line T(1)24C showed the highest accumulation of Ni (251.9 ± 0.014 mg/kg) and the lowest TF value (TFT(1)24C=0.0875) at 60 ppm Ni.

  13. Delta Revival: Restoring a California Ecosystem

    USGS Publications Warehouse

    U.S. Geological Survey; California Bay Delta Authority

    2003-01-01

    'Delta Revival: Restoring a California Ecosystem' shows scientists from many disciplines working together to guide the unprecendented restoration of the Sacramento- San Joaquin Delta east of San Francisco Bay.

  14. Delta launch vehicle inertial guidance system (DIGS)

    NASA Technical Reports Server (NTRS)

    Duck, K. I.

    1973-01-01

    The Delta inertial guidance system, part of the Delta launch vehicle improvement effort, has been flown on three launches and was found to perform as expected for a variety of mission profiles and vehicle configurations.

  15. Abeta42 gene vaccine prevents Abeta42 deposition in brain of double transgenic mice.

    PubMed

    Qu, Bao-Xi; Xiang, Qun; Li, Liping; Johnston, Stephen Albert; Hynan, Linda S; Rosenberg, Roger N

    2007-09-15

    Abeta42 peptide aggregation and deposition is an important component of the neuropathology of Alzheimer's disease (AD). Gene-gun mediated gene vaccination targeting Abeta42 is a potential method to prevent and treat AD. APPswe/PS1DeltaE9 transgenic (Tg) mice were immunized with an Abeta42 gene construct delivered by the gene gun. The vaccinated mice developed Th2 antibodies (IgG1) against Abeta42. The Abeta42 levels in brain were decreased by 41% and increased in plasma 43% in the vaccinated compared with control mice as assessed by ELISA analysis. Abeta42 plaque deposits in cerebral cortex and hippocampus were reduced by 51% and 52%, respectively, as shown by quantitative immunolabeling. Glial cell activation was also significantly attenuated in vaccinated compared with control mice. One rhesus monkey was vaccinated and developed anti-Abeta42 antibody. These new findings advance significantly our knowledge that gene-gun mediated Abeta42 gene immunization effectively induces a Th2 immune response and reduces the Abeta42 levels in brain in APPswe/PS1DeltaE9 mice. Abeta42 gene vaccination may be safe and efficient immunotherapy for AD. PMID:17574274

  16. Delta launch vehicle accident investigation

    NASA Astrophysics Data System (ADS)

    1986-03-01

    The text of the testimony given by several witnesses during the House hearings on the Delta launch vehicle accident of May 3, 1986 is given. Pre-launch procedures, failure analysis, the possibility of sabotage, and design and testing are among the topics discussed.

  17. N-{Delta} weak transition

    SciTech Connect

    Graczyk, Krzysztof M.

    2011-11-23

    A short review of the Rein-Sehgal and isobar models is presented. The attention is focused on the nucleon-{Delta}(1232) weak transition form-factors. The results of the recent re-analyses of the ANL and BNL bubble chamber neutrino-deuteron scattering data are discussed.

  18. Phytoplankton fuels Delta food web

    USGS Publications Warehouse

    Jassby, Alan D.; Cloern, James E.; Muller-Solger, A. B.

    2003-01-01

    Populations of certain fishes and invertebrates in the Sacramento-San Joaquin Delta have declined in abundance in recent decades and there is evidence that food supply is partly responsible. While many sources of organic matter in the Delta could be supporting fish populations indirectly through the food web (including aquatic vegetation and decaying organic matter from agricultural drainage), a careful accounting shows that phytoplankton is the dominant food source. Phytoplankton, communities of microscopic free-floating algae, are the most important food source on a Delta-wide scale when both food quantity and quality are taken into account. These microscopic algae have declined since the late 1960s. Fertilizer and pesticide runoff do not appear to be playing a direct role in long-term phytoplankton changes; rather, species invasions, increasing water transparency and fluctuations in water transport are responsible. Although the potential toxicity of herbicides and pesticides to plank- ton in the Delta is well documented, the ecological significance remains speculative. Nutrient inputs from agricultural runoff at current levels, in combination with increasing transparency, could result in harmful al- gal blooms. 

  19. Spongeplant Spreading in the Delta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Invasive, exotic aquatic plants impact a range of important economic and ecological functions in the Sacramento-San Joaquin Delta of California, and the state now spends over $5 million to control water hyacinth and Brazilian waterweed. In 2007, a new exotic floating plant South American Spongeplan...

  20. Delta-ALA urine test

    MedlinePlus

    ... increased level of urinary delta-ALA may indicate: Lead poisoning Porphyria (several types) A decreased level may occur ... A.M. Editorial team. Related MedlinePlus Health Topics Lead Poisoning Porphyria Browse the Encyclopedia A.D.A.M., ...

  1. Revisiting double Dirac delta potential

    NASA Astrophysics Data System (ADS)

    Ahmed, Zafar; Kumar, Sachin; Sharma, Mayank; Sharma, Vibhu

    2016-07-01

    We study a general double Dirac delta potential to show that this is the simplest yet still versatile solvable potential to introduce double wells, avoided crossings, resonances and perfect transmission (T = 1). Perfect transmission energies turn out to be the critical property of symmetric and anti-symmetric cases wherein these discrete energies are found to correspond to the eigenvalues of a Dirac delta potential placed symmetrically between two rigid walls. For well(s) or barrier(s), perfect transmission (or zero reflectivity, R(E)) at energy E=0 is non-intuitive. However, this has been found earlier and called the ‘threshold anomaly’. Here we show that it is a critical phenomenon and we can have 0≤slant R(0)\\lt 1 when the parameters of the double delta potential satisfy an interesting condition. We also invoke a zero-energy and zero curvature eigenstate (\\psi (x)={Ax}+B) of the delta well between two symmetric rigid walls for R(0)=0. We resolve that the resonant energies and the perfect transmission energies are different and they arise differently.

  2. Maintenance of large deltas through channelization

    NASA Astrophysics Data System (ADS)

    Giosan, L.; Constatinescu, S.; Filip, F.

    2013-12-01

    A new paradigm for delta restoration is currently taking shape using primarily Mississippi delta examples. Here we propose an alternative for delta maintenance primarily envisioned for wave-influenced deltas based on Danube delta experiences. Over the last half century, while the total sediment load of the Danube dramatically decreased due to dam construction on tributaries and its mainstem, a grand experiment was inadvertently run in the Danube delta: the construction of a dense network of canals, which almost tripled the water discharge toward the interior of the delta plain. We use core-based and chart-based sedimentation rates and patterns to explore the delta transition from the natural to an anthropogenic regime, to understand the effects of far-field damming and near-field channelization, and to construct a conceptual model for delta development as a function sediment partition between the delta plain and the delta coastal fringe. We show that sediment fluxes increased to the delta plain due to channelization, counteracting sea level rise. In turn, the delta coastal fringe was most impacted by the Danube's sediment load collapse. Furthermore, we show that morphodynamic feedbacks at the river mouth are crucial in trapping sediment near the coast and constructing wave-dominated deltas or lobes or delaying their destruction. As a general conclusion, we suggest that increased channelization that mimics and enhances natural processes may provide a simple solution for keeping delta plains above sea level and that abandonment of wave-dominated lobes may be the most long term efficient solution for protecting the internal fluvial regions of deltas and provide new coastal growth downcoast.

  3. Assessment of Delta Nitrogen Losses (Delta NL) at the Field Level

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We defined a new concept of field-level delta nitrogen (N) losses (Delta NL) as a comparison between management scenarios. We defined delta nitrogen losses (Delta NL) as a function of improved N use efficiencies of field management scenarios that reduce the average N inputs and/or modify other manag...

  4. The calculation of T{sub {delta}} and V{sub {delta}} in austenitic steel

    SciTech Connect

    Dai Qixun; Yang Ruzeng

    1997-03-01

    The relation between the {gamma}/{gamma} + {delta} boundary temperature, T{sub {delta}}, of austenitic steels and the equivalent weights, [Cr] and [Ni], has been studied, as has the law of variation of the {delta} phase volume, V{sub {delta}}, with temperature. With the aid of a computer, the following regression expressions have been derived from the experimental results: T{sub {delta}} ({degree}C) =- T{sub 4} {minus} 21.2[Cr] + 15.8[Ni] {minus} 223; V{sub {delta}} (%) = 0.715 exp [0.015(T {minus} T{sub {delta}})]. Satisfactory results have been obtained by using these regression expressions.

  5. Generation of transgenic Hydra by embryo microinjection.

    PubMed

    Juliano, Celina E; Lin, Haifan; Steele, Robert E

    2014-01-01

    As a member of the phylum Cnidaria, the sister group to all bilaterians, Hydra can shed light on fundamental biological processes shared among multicellular animals. Hydra is used as a model for the study of regeneration, pattern formation, and stem cells. However, research efforts have been hampered by lack of a reliable method for gene perturbations to study molecular function. The development of transgenic methods has revitalized the study of Hydra biology(1). Transgenic Hydra allow for the tracking of live cells, sorting to yield pure cell populations for biochemical analysis, manipulation of gene function by knockdown and over-expression, and analysis of promoter function. Plasmid DNA injected into early stage embryos randomly integrates into the genome early in development. This results in hatchlings that express transgenes in patches of tissue in one or more of the three lineages (ectodermal epithelial, endodermal epithelial, or interstitial). The success rate of obtaining a hatchling with transgenic tissue is between 10% and 20%. Asexual propagation of the transgenic hatchling is used to establish a uniformly transgenic line in a particular lineage. Generating transgenic Hydra is surprisingly simple and robust, and here we describe a protocol that can be easily implemented at low cost. PMID:25285460

  6. Glyphostate-drift but not herbivory alters the rate of transgene flow from single and stacked trait transgenic canola (Brassica napus L.) to non-transgenic B. napus and B. rapa

    EPA Science Inventory

    While transgenic plants can offer agricultural benefits, the escape of transgenes out of crop fields is a major environmental concern. Escape of transgenic herbicide resistance has occurred between transgenic Brassica napus (canola) and weedy species in numerous locations. In t...

  7. Transgenic fish: present status and future directions.

    PubMed

    Hew, C L

    1989-06-01

    Successful production of transgenic fish by gene transfer technology is a very important breakthrough in the techniques of genetic manipulation in animals. This will have an impact of an unprecedented scale in fish biology, aquaculture and mariculture. This is a summary of the workshop on the Transgenic Fish presented at this Symposium. The Workshop discussed the current knowledge, experimental difficulties and related topics of the transgenic fish. It recommended further research on better gene constructs, methods development, safety containment and the closer collaboration of researchers of different disciplines. PMID:24221801

  8. Expression of multiple proteins in transgenic plants

    DOEpatents

    Vierstra, Richard D.; Walker, Joseph M.

    2002-01-01

    A method is disclosed for the production of multiple proteins in transgenic plants. A DNA construct for introduction into plants includes a provision to express a fusion protein of two proteins of interest joined by a linking domain including plant ubiquitin. When the fusion protein is produced in the cells of a transgenic plant transformed with the DNA construction, native enzymes present in plant cells cleave the fusion protein to release both proteins of interest into the cells of the transgenic plant. Since the proteins are produced from the same fusion protein, the initial quantities of the proteins in the cells of the plant are approximately equal.

  9. [Transgenic technology and soybean quality improvement].

    PubMed

    Cheng, Hao; Jin, Hang-Xia; Gai, Jun-Yi; Yu, De-Yue

    2011-05-01

    Soybean is an important source of edible oil, protein and protein diet. The breeding process of high quality soybean can be accelerated via employment of transgenic technology, by which the key genes for soybean quality traits could be directly manipulated. Thus, various soybean varieties could be bred to fulfill different needs for specific consumers. Here, we reviewed the contribution of transgenic technology to improvement of soybean qualities in recent years. We also introduce some newly developed safe transgenic technologies and hope this information could relieve some concerns on the GM food. PMID:21586389

  10. Comparison of sugar, acids, and volatile composition in raspberry bushy dwarf virus-resistant transgenic raspberries and the wild type 'meeker' (rubus idaeus L.).

    PubMed

    Malowicki, Sarah M M; Martin, Robert; Qian, Michael C

    2008-08-13

    Raspberry bushy dwarf virus (RBDV) causes a significant reduction in yield and quality in raspberry and raspberry-blackberry hybrid. Genetic modifications were made to 'Meeker' red raspberries to impart RBDV resistance. The RBDV-resistant transgenic and wild type 'Meeker' plants were grown in Oregon and Washington, and the fruits were harvested in the 2004 and 2005 growing seasons. Year-to-year and site-to-site variations were observed for the degrees Brix and titratable acidity, with Oregon raspberries having slightly higher degrees Brix and lower titratable acidity than Washington raspberries. Twenty-nine volatile compounds were quantified using stir bar sorptive extraction (SBSE) paired with gas chromatography-mass spectrometry (GC-MS). There were very few differences in volatile concentrations between the transgenic varieties and the wild type 'Meeker'. Much larger variations were observed between sites and harvest seasons. Raspberries grown in Oregon appeared to have higher concentrations of delta-octalactone, delta-decalactone, geraniol, and linalool. Chiral analysis of alpha-ionone, alpha-pinene, linalool, terpinen-4-ol, delta-octalactone, and delta-decalactone demonstrated a much higher percentage of one isomer over the other, particularly alpha-ionone, alpha-pinene, delta-octalactone, and delta-decalactone, with more than 90% of one isomer, while a racemic mixture was observed for linalool. The isomeric analysis revealed very little variation between varieties, locations, or years. The flavor compounds tested in this study did not show any difference between the transgenic lines and the wild type 'Meeker' raspberry. PMID:18598047

  11. Changes in Oleic Acid Content of Transgenic Soybeans by Antisense RNA Mediated Posttranscriptional Gene Silencing

    PubMed Central

    Zhang, Ling; Yang, Xiang-dong; Zhang, Yuan-yu; Yang, Jing; Qi, Guang-xun; Guo, Dong-quan; Xing, Guo-jie; Yao, Yao; Xu, Wen-jing; Li, Hai-yun; Li, Qi-yun; Dong, Ying-shan

    2014-01-01

    The Delta-12 oleate desaturase gene (FAD2-1), which converts oleic acid into linoleic acid, is the key enzyme determining the fatty acid composition of seed oil. In this study, we inhibited the expression of endogenous Delta-12 oleate desaturase GmFad2-1b gene by using antisense RNA in soybean Williams 82. By employing the soybean cotyledonary-node method, a part of the cDNA of soybean GmFad2-1b 801 bp was cloned for the construction of a pCAMBIA3300 vector under the soybean seed promoter BCSP. Leaf painting, LibertyLink strip, PCR, Southern blot, qRT-PCR, and fatty acid analysis were used to detect the insertion and expression of GmFad2-1b in the transgenic soybean lines. The results indicate that the metabolically engineered plants exhibited a significant increase in oleic acid (up to 51.71%) and a reduction in palmitic acid (to <3%) in their seed oil content. No structural differences were observed between the fatty acids of the transgenic and the nontransgenic oil extracts. PMID:25197629

  12. Overview: Engineering transgenic constructs and mice

    PubMed Central

    Haruyama, Naoto; Cho, Andrew; Kulkarni, Ashok B

    2009-01-01

    Cell biology research encompasses everything from single cells to whole animals. Recent discoveries concerning particular gene functions can be applied to the whole animal for understanding genotype-phenotype relationships underlying disease mechanisms. For this reason, genetically manipulated mouse models are now considered essential to correctly understand disease processes in whole animals. This unit provides the basic mouse technologies used to generate conventional transgenic mice, which represents gain-of-function approach. First, an overview of the transgenic construct design is presented. This unit then explains basic strategies for the identification and establishment of independent transgenic mouse lines, followed by comments on historical and emerging techniques, and then on typical problems that are encountered when researchers start to generate transgenic mice. PMID:19283728

  13. AN APPROACH TO TRANSGENIC CROP MONITORING

    EPA Science Inventory

    Remote sensing by aerial or satellite images may provide a method of identifying transgenic pesticidal crop distribution in the landscape. Genetically engineered crops containing bacterial gene(s) that express an insecticidal protein from Bacillus thuringiensis (Bt) are regulated...

  14. [Review of transgenic crop breeding in China].

    PubMed

    Huang, Dafang

    2015-06-01

    The development history and fundamental experience of transgenic crops (Genetically modified crops) breeding in China for near 30 years were reviewed. It was illustrated that a scientific research, development and industrialization system of transgenic crops including gene discovery, transformation, variety breeding, commercialization, application and biosafety assessment has been initially established which was few in number in the world. The research innovative capacity of transgenic cotton, rice and corn has been lifted. The research features as well as relative advantages have been initially formed. The problems and challenges of transgenic crop development were discussed. In addition, three suggestions of promoting commercialization, speeding up implementation of the Major National Project of GM Crops, and enhancing science communication were made. PMID:26672365

  15. Bacillus thuringiensis (Bt) transgenic crop: an environment friendly insect-pest management strategy.

    PubMed

    Kumar, Suresh; Chandra, Amaresh; Pandey, K C

    2008-09-01

    Introduction of DDT (dichloro-diphenyl-trichloroethane) and following move towards indiscriminate use of synthetic chemical insecticides led to the contamination of water and food sources, poisoning of non-target beneficial insects and development of insect-pests resistant to the chemical insecticides. Increased public concems about the adverse environmental effects of indiscriminate use of chemical insecticides prompted search of altemative methods for insect-pest control. One of the promising alternatives has been the use of biological control agents. There is well-documented history of safe application of Bt (B. thuringiensis, a gram positive soil bacterium) as effective biopesticides and a number of reports of expression of delta-endotoxin gene(s) in crop plants are available. Only a few insecticidal sprays are required on Bt transgenic crops, which not only save cost and time, but also reduce health risks. Insects exhibit remarkable ability to develop resistance to different insecticidal compounds, which raises concern about the unsystematic use of Bt transgenic technology also. Though resistance to Bt products among insect species under field conditions has been rare, laboratory studies show that insects are capable of developing high levels of resistance to one ormore Cry proteins. Now it is generally agreed that 'high-dose/refuge strategy' is the most promising and practical approach to prolong the effectiveness of Bt toxins. Although manybiosafety concerns, ethical and moral issues exist, area under Bt transgenic crops is rapidly increasing and they are cultivated on more than 32 million hectares world over Even after reservation of European Union (EU) for acceptance of geneticaly modified (GM) crops, 6 out of 25 countries have already adopted Bt crops and many otherindustrial countries will adopt Bt transgenic crops in near future. While the modem biotechnology has been recognized to have a great potential for the promotion of human well-being, adoption

  16. Deformation characteristics of {delta} phase in the delta-processed Inconel 718 alloy

    SciTech Connect

    Zhang, H.Y.; Zhang, S.H.; Cheng, M.; Li, Z.X.

    2010-01-15

    The hot working characteristics of {delta} phase in the delta-processed Inconel 718 alloy during isothermal compression deformation at temperature of 950 deg. C and strain rate of 0.005 s{sup -1}, were studied by using optical microscope, scanning electron microscope and quantitative X-ray diffraction technique. The results showed that the dissolution of plate-like {delta} phase and the precipitation of spherical {delta} phase particles coexisted during the deformation, and the content of {delta} phase decreased from 7.05 wt.% to 5.14 wt.%. As a result of deformation breakage and dissolution breakage, the plate-like {delta} phase was spheroidized and transferred to spherical {delta} phase particles. In the center with largest strain, the plate-like {delta} phase disappeared and spherical {delta} phase appeared in the interior of grains and grain boundaries.

  17. The delta (delta) gap: an approach to mixed acid-base disorders.

    PubMed

    Wrenn, K

    1990-11-01

    The anion gap (AG) is a helpful, yet underused, clinical tool. Not only does the presence of a high AG suggest a certain differential, but knowledge of the relationship between the rise in AG (delta AG) and the fall in bicarbonate (delta HCO3) is important in understanding mixed acid-based disorders. Simple arithmetic converts this relationship into a numerical value, the delta gap (delta gap). The delta gap = delta AG - delta HCO3. If the delta gap is significantly positive (greater than +6), a metabolic alkalosis is usually present because the rise in AG is more than the fall in HCO3. Conversely, if the delta gap is significantly negative (less than -6), then a hyperchloremic acidosis is usually present because the rise in AG is less than the fall in HCO3. Familarity with the relationship between the changes in AG and HCO3 can be useful in unmasking occult metabolic disorders. PMID:2240729

  18. Transgene flow: facts, speculations and possible countermeasures.

    PubMed

    Ryffel, Gerhart U

    2014-01-01

    Convincing evidence has accumulated that unintended transgene escape occurs in oilseed rape, maize, cotton and creeping bentgrass. The escaped transgenes are found in variant cultivars, in wild type plants as well as in hybrids of sexually compatible species. The fact that in some cases stacked events are present that have not been planted commercially, implies unintended recombination of transgenic traits. As the consequences of this continuous transgene escape for the ecosystem cannot be reliably predicted, I propose to use more sophisticated approaches of gene technology in future. If possible GM plants should be constructed using either site-directed mutagenesis or cisgenic strategies to avoid the problem of transgene escape. In cases where a transgenic trait is needed, efficient containment should be the standard approach. Various strategies available or in development are discussed. Such a cautious approach in developing novel types of GM crops will enhance the sustainable potential of GM crops and thus increase the public trust in green gene technology. PMID:25523171

  19. Future Deltas Utrecht University research focus area: towards sustainable management of sinking deltas

    NASA Astrophysics Data System (ADS)

    Stouthamer, E.; van Asselen, S.

    2015-11-01

    Deltas are increasingly under pressure from human impact and climate change. To deal with these pressures that threat future delta functioning, we need to understand interactions between physical, biological, chemical and social processes in deltas. This requires an integrated approach, in which knowledge on natural system functioning is combined with knowledge on spatial planning, land and water governance and legislative frameworks. In the research focus area Future Deltas of Utrecht University an interdisciplinary team from different research groups therefore works together. This allows developing integrated sustainable and resilient delta management strategies, which is urgently needed to prevent loss of vital delta services.

  20. A Primer for Using Transgenic Insecticidal Cotton in Developing Countries

    PubMed Central

    Showalter, Ann M.; Heuberger, Shannon; Tabashnik, Bruce E.; Carrière, Yves

    2009-01-01

    Many developing countries face the decision of whether to approve the testing and commercial use of insecticidal transgenic cotton and the task of developing adequate regulations for its use. In this review, we outline concepts and provide information to assist farmers, regulators and scientists in making decisions concerning this technology. We address seven critical topics: 1) molecular and breeding techniques used for the development of transgenic cotton cultivars, 2) properties of transgenic cotton cultivars and their efficacy against major insect pests, 3) agronomic performance of transgenic cotton in developing countries, 4) factors affecting transgene expression, 5) impact of gene flow between transgenic and non-transgenic cotton, 6) non-target effects of transgenic cotton, and 7) management of pest resistance to transgenic cotton. PMID:19613464

  1. COMMD1 regulates the delta epithelial sodium channel ({delta}ENaC) through trafficking and ubiquitination

    SciTech Connect

    Chang, Tina; Ke, Ying; Ly, Kevin; McDonald, Fiona J.

    2011-08-05

    Highlights: {yields} The COMM domain of COMMD1 mediates binding to {delta}ENaC. {yields} COMMD1 reduces the cell surface population of {delta}ENaC. {yields} COMMD1 increases the population of {delta}ENaC-ubiquitin. {yields} Both endogenous and transfected {delta}ENaC localize with COMMD1 and transferrin suggesting they are located in early/recycling endosomes. -- Abstract: The delta subunit of the epithelial sodium channel ({delta}ENaC) is a member of the ENaC/degenerin family of ion channels. {delta}ENaC is distinct from the related {alpha}-, {beta}- and {gamma}ENaC subunits, known for their role in sodium homeostasis and blood pressure control, as {delta}ENaC is expressed in brain neurons and activated by external protons. COMMD1 (copper metabolism Murr1 domain 1) was previously found to associate with and downregulate {delta}ENaC activity. Here, we show that COMMD1 interacts with {delta}ENaC through its COMM domain. Co-expression of {delta}ENaC with COMMD1 significantly reduced {delta}ENaC surface expression, and led to an increase in {delta}ENaC ubiquitination. Immunocytochemical and confocal microscopy studies show that COMMD1 promoted localization of {delta}ENaC to the early/recycling endosomal pool where the two proteins were localized together. These results suggest that COMMD1 downregulates {delta}ENaC activity by reducing {delta}ENaC surface expression through promoting internalization of surface {delta}ENaC to an intracellular recycling pool, possibly via enhanced ubiquitination.

  2. A transgenic perspective on plant functional genomics.

    PubMed

    Pereira, A

    2000-01-01

    Transgenic crops are very much in the news due to the increasing public debate on their acceptance. In the scientific community though, transgenic plants are proving to be powerful tools to study various aspects of plant sciences. The emerging scientific revolution sparked by genomics based technologies is producing enormous amounts of DNA sequence information that, together with plant transformation methodology, is opening up new experimental opportunities for functional genomics analysis. An overview is provided here on the use of transgenic technology for the functional analysis of plant genes in model plants and a link made to their utilization in transgenic crops. In transgenic plants, insertional mutagenesis using heterologous maize transposons or Agrobacterium mediated T-DNA insertions, have been valuable tools for the identification and isolation of genes that display a mutant phenotype. To discover functions of genes that do not display phenotypes when mutated, insertion sequences have been engineered to monitor or change the expression pattern of adjacent genes. These gene detector insertions can detect adjacent promoters, enhancers or gene exons and precisely reflect the expression pattern of the tagged gene. Activation tag insertions can mis-express the adjacent gene and confer dominant phenotypes that help bridge the phenotype gap. Employment of various forms of gene silencing technology broadens the scope of recovering knockout phenotypes for genes with redundant function. All these transgenic strategies describing gene-phenotype relationships can be addressed by high throughput reverse genetics methods that will help provide functions to the genes discovered by genome sequencing. The gene functions discovered by insertional mutagenesis and silencing strategies along with expression pattern analysis will provide an integrated functional genomics perspective and offer unique applications in transgenic crops. PMID:11131004

  3. Phycoremediation of heavy metals using transgenic microalgae.

    PubMed

    Rajamani, Sathish; Siripornadulsil, Surasak; Falcao, Vanessa; Torres, Moacir; Colepicolo, Pio; Sayre, Richard

    2007-01-01

    Microalgae account for most of the biologically sequestered trace metals in aquatic environments. Their ability to adsorb and metabolize trace metals is associated with their large surface:volume ratios, the presence of high-affinity, metal-binding groups on their cell surfaces, and efficient metal uptake and storage systems. Microalgae may bind up to 10% of their biomass as metals. In addition to essential trace metals required for metabolism, microalgae can efficiently sequester toxic heavy metals. Toxic heavy metals often compete with essential trace metals for binding to and uptake into cells. Recently, transgenic approaches have been developed to further enhance the heavy metal specificity and binding capacity of microalgae with the objective of using these microalgae for the treatment of heavy metal contaminated wastewaters and sediments. These transgenic strategies have included the over expression of enzymes whose metabolic products ameliorate the effects of heavy metal-induced stress, and the expression of high-affinity, heavy metal binding proteins on the surface and in the cytoplasm of transgenic cells. The most effective strategies have substantially reduced the toxicity of heavy metals allowing transgenic cells to grow at wild-type rates in the presence of lethal concentrations of heavy metals. In addition, the metal binding capacity of transgenic algae has been increased five-fold relative to wild-type cells. Recently, fluorescent heavy metal biosensors have been developed for expression in transgenic Chlamydomonas. These fluorescent biosensor strains can be used for the detection and quantification of bioavailable heavy metals in aquatic environments. The use of transgenic microalgae to monitor and remediate heavy metals in aquatic environments is not without risk, however. Strategies to prevent the release of live microalgae having enhanced metal binding properties are described. PMID:18161494

  4. Effects of transgenic rootstocks on growth and development of non-transgenic scion cultivars in apple.

    PubMed

    Smolka, Anders; Li, Xue-Yuan; Heikelt, Catrin; Welander, Margareta; Zhu, Li-Hua

    2010-12-01

    Although cultivation of genetic modified (GM) annual crops has been steadily increasing in the recent 10 years, the commercial cultivation of GM fruit tree is still very limited and reports of field trials on GM fruit trees are rare. This is probably because development and evaluation of GM fruit trees require a long period of time due to long life cycles of trees. In this study, we report results from a field trial on three rolB transgenic dwarfing apple rootstocks of M26 and M9 together with non-transgenic controls grafted with five non-transgenic scion cultivars. We intended to investigate the effects of transgenic rootstock on non-transgenic scion cultivars under natural conditions as well as to evaluate the potential value of using the rolB gene to modify difficult-to-root rootstocks of fruit trees. The results showed that all rolB transgenic rootstocks significantly reduced vegetative growth including tree height regardless of scion cultivar, compared with the non-transgenic rootstocks. Flowering and fruiting were also decreased for cultivars grown on the transgenic rootstocks in most cases, but the fruit quality was not clearly affected by the transgenic rootstocks. Cutting experiment and RT-PCR analysis showed that the rolB gene was stably expressed under field conditions. PCR and RT-PCR analyses displayed that the rolB gene or its mRNA were not detectable in the scion cultivars, indicating no translocation of the transgene or its mRNA from rootstock to scion. Our results suggest that rolB modified rootstocks should be used in combination with vigorous scion cultivars in order to obtain sufficient vegetative growth and good yield. Alternatively, the rolB gene could be used to dwarf vigorous rootstocks of fruit trees or produce bonzai plants as it can significantly reduce the vegetative growth of plants. PMID:20135223

  5. Navigational Use of Cassini Delta V Telemetry

    NASA Technical Reports Server (NTRS)

    Roth, Duane C.; Antreasian, Peter G.; Ardalan, Shadan M.; Criddle, Kevin E.; Goodson, Troy; Ionasescu, Rodica; Jones, Jeremy B.; Parcher, Daniel W.; Pelletier, Frederic J.; Thompson, Paul F.; Vaughan, Andrew T.

    2008-01-01

    Telemetry data are used to improve navigation of the Saturn orbiting Cassini spacecraft. Thrust induced delta V's are computed on-board the spacecraft, recorded in telemetry, and downlinked to Earth. This paper discusses how and why the Cassini Navigation team utilizes spacecraft delta V telemetry. Operational changes making this information attractive to the Navigation Team will be briefly discussed, as will spacecraft hardware and software algorithms responsible for the on-board computation. An analysis of past delta V telemetry, providing calibrations and accuracies that can be applied to the estimation of future delta V activity, is described.

  6. From Natural to Design River Deltas

    NASA Astrophysics Data System (ADS)

    Giosan, Liviu

    2016-04-01

    Productive and biologically diverse, deltaic lowlands attracted humans since prehistory and may have spurred the emergence of the first urban civilizations. Deltas continued to be an important nexus for economic development across the world and are currently home for over half a billion people. But recently, under the double whammy of sea level rise and inland sediment capture behind dams, they have become the most threatened coastal landscape. Here I will address several deceptively simple questions to sketch some unexpected answers using example deltas from across the world from the Arctic to the Tropics, from the Danube to the Indus, Mississippi to Godavari and Krishna, Mackenzie to Yukon. What is a river delta? What is natural and what is not in a river delta? Are the geological and human histories of a delta important for its current management? Is maintaining a delta the same to building a new one? Can we design better deltas than Nature? These answers help us see clearly that survival of deltas in the next century depends on human intervention and is neither assured nor simple to address or universally applicable. Empirical observations on the hydrology, geology, biology and biochemistry of deltas are significantly lagging behind modeling capabilities endangering the applicability of numerical-based reconstruction solutions and need to be ramped up significantly and rapidly across the world.

  7. The transgenic animal platform for biopharmaceutical production.

    PubMed

    Bertolini, L R; Meade, H; Lazzarotto, C R; Martins, L T; Tavares, K C; Bertolini, M; Murray, J D

    2016-06-01

    The recombinant production of therapeutic proteins for human diseases is currently the largest source of innovation in the pharmaceutical industry. The market growth has been the driving force on efforts for the development of new therapeutic proteins, in which transgenesis emerges as key component. The use of the transgenic animal platform offers attractive possibilities, residing on the low production costs allied to high productivity and quality of the recombinant proteins. Although many strategies have evolved over the past decades for the generation of transgenic founders, transgenesis in livestock animals generally faces some challenges, mainly due to random transgene integration and control over transgene copy number. But new developments in gene editing with CRISPR/Cas system promises to revolutionize the field for its simplicity and high efficiency. In addition, for the final approval of any given recombinant protein for animal or human use, the production and characterization of bioreactor founders and expression patterns and functionality of the proteins are technical part of the process, which also requires regulatory and administrative decisions, with a large emphasis on biosafety. The approval of two mammary gland-derived recombinant proteins for commercial and clinical use has boosted the interest for more efficient, safer and economic ways to generate transgenic founders to meet the increasing demand for biomedical proteins worldwide. PMID:26820414

  8. Manipulation of glutathione metabolism in transgenic plants.

    PubMed

    Creissen, G; Broadbent, P; Stevens, R; Wellburn, A R; Mullineaux, P

    1996-05-01

    There is clear potential for the genetic manipulation of key enzymes involved in stress metabolism in transgenic plants. However, the data emerging so far from such experiments are equivocal. The detailed analysis of stress responses in progeny of primary transgenics, coupled with comparisons with control transgenic plants that do not contain the GR transgene, allows us to take into account the possible variation in response to stress associated with regeneration of plants from tissue culture. The picture that is now beginning to emerge with respect to the role of GR in stress protection is that, although there are clearly benefits to be had from overexpression of the enzymes, there is no direct correlation between enzyme levels and stress tolerance. It may be that overexpression of the cytosolic isoform (gor2) will prove to be of greater benefit. Furthermore, the types of stresses to which transgenic plants have been exposed in order to assess the consequences of oxidative stress tolerance cannot reproduce those that will experienced in field conditions. Only when plants with higher GR levels and increased glutathione synthesis capacity are grown in field trials will it be possible to make a full assessment of the benefits of engineering plants with altered glutathione metabolism. PMID:8736785

  9. Neighbor effects of neurons bearing protective transgenes

    PubMed Central

    Lee, Angela L; Campbell, Laura B; Sapolsky, Robert M

    2010-01-01

    Viral vectors bearing protective transgenes can decrease neurotoxicity after varied necrotic insults. A neuron that dies necrotically releases glutamate, calcium and reactive oxygen species, thereby potentially damaging neighboring neurons. This raises the possibility that preventing such neuron death via gene therapy can secondarily protect neighboring neurons that, themselves, do not express a protective transgene. We determined whether such “good neighbor” effects occur, by characterizing neurons that, while uninfected themselves, are in close proximity to a transgene-bearing neuron. We tested two genes whose overexpression protects against excitotoxicity: anti-apoptotic Bcl-2, and a calcium-activated K+ channel, SK2. Using herpes simplex virus type 2-mediated transgene delivery to hippocampal cultures, we observed “good neighbor” effects on neuronal survival following an excitotoxic insult. However, in the absence of insult, “bad neighbor effects” could also occur (i.e., where being in proximity to a neuron constitutively expressing one of those transgenes is deleterious). We also characterized the necessity for cell-cell contact for these effects. These phenomena may have broad implications for the efficacy of gene overexpression strategies in the CNS. PMID:20417625

  10. Comments on the slip factor and the relation Delta phi = -h Delta theta

    SciTech Connect

    Ng, K.Y.; /Fermilab

    2009-09-01

    The definition of the slip factor can be obtained from the phase equation. However, a derivation using the relation {Delta}{phi} = -h{Delta}{theta} leads to a different slip-factor definition. This apparent paradox is examined in detail and resolved. Here {Delta}{phi} is the rf phase difference and {Delta}{theta} is the azimuthal phase difference around the accelerator ring between an off-momentum particle and the synchronous particle, while h is the rf harmonic.

  11. [Evaluation of Salt Tolerance of Transgenic Tobacco Plants Bearing with P5CS1 Gene of Arabidopsis thaliana].

    PubMed

    Ibragimova, S M; Trifonova, E A; Filipenko, E A; Shymny, V K

    2015-12-01

    Arabidopsis thaliana delta1-pyrroline-5-carhoxylate synthase 1 gene (P5CS1) cDNA was cloned under the control of the potent constitutive 35S RNA promoter of the cauliflower mosaic virus and transferred into genome of tobacco cv. Petit Havana SR-1 (Nicotiana tabacum L.) plants. It is shown that the constitutive level of proline in the transgenic plants T0 exceeds that of the SR1 reference line by 1.5 to 4 times. Under conditions of salt stress (200, 300 mM NaCl) T1-generation transgenic plants in early stages of development formed a large biomass, developed more quickly, and had a higher rate of root growth compared to the control, which confirms the involvement of the P5CS1 gene in molecular mechanisms of stress resistance in plants. PMID:27055296

  12. Screening for transgenic Japanese quail offspring.

    PubMed

    Poynter, Greg; Huss, David; Lansford, Rusty

    2009-01-01

    After mosaic founder breeding pairs of Japanese quail start to produce fertile eggs, the hatchlings must be screened for germ-line transmission to the subsequent G1 generation. This article describes how to isolate hatchling genomic DNA from the chorioallantoic membrane (CAM), which remains inside the egg after hatching. Collecting genomic DNA from the CAM decreases the hatchling's stress during handling and eliminates the need for a blood draw. By following this protocol, the CAM of a single egg will provide 50 microg or more of high-quality genomic DNA. The article also describes how to screen the genomic DNA samples for the transgene by the polymerase chain reaction (PCR). PCR genotyping should be used for screening hatchlings with a nonfluorescent transgene or with a fluorescently labeled transgene that does not lend itself well to phenotypic screening. PMID:20147014

  13. Toxins for Transgenic Resistance to Hemipteran Pests

    PubMed Central

    Chougule, Nanasaheb P.; Bonning, Bryony C.

    2012-01-01

    The sap sucking insects (Hemiptera), which include aphids, whiteflies, plant bugs and stink bugs, have emerged as major agricultural pests. The Hemiptera cause direct damage by feeding on crops, and in some cases indirect damage by transmission of plant viruses. Current management relies almost exclusively on application of classical chemical insecticides. While the development of transgenic crops expressing toxins derived from the bacterium Bacillus thuringiensis (Bt) has provided effective plant protection against some insect pests, Bt toxins exhibit little toxicity against sap sucking insects. Indeed, the pest status of some Hemiptera on Bt-transgenic plants has increased in the absence of pesticide application. The increased pest status of numerous hemipteran species, combined with increased prevalence of resistance to chemical insecticides, provides impetus for the development of biologically based, alternative management strategies. Here, we provide an overview of approaches toward transgenic resistance to hemipteran pests. PMID:22822455

  14. Transgenic Mouse Technology: Principles and Methods

    PubMed Central

    Kumar, T. Rajendra; Larson, Melissa; Wang, Huizhen; McDermott, Jeff; Bronshteyn, Illya

    2014-01-01

    Introduction of foreign DNA into the mouse germ line is considered a major technical advancement in the fields of developmental biology and genetics. This technology now referred to as transgenic mouse technology has revolutionized virtually all fields of biology and provided new genetic approaches to model many human diseases in a whole animal context. Several hundreds of transgenic lines with expression of foreign genes specifically targeted to desired organelles/cells/tissues have been characterized. Further, the ability to spatio-temporally inactivate or activate gene expression in vivo using the “Cre-lox” technology has recently emerged as a powerful approach to understand various developmental processes including those relevant to molecular endocrinology. In this chapter, we will discuss the principles of transgenic mouse technology, and describe detailed methodology standardized at our Institute. PMID:19763515

  15. Generation of BAC Transgenic Epithelial Organoids

    PubMed Central

    Schwank, Gerald; Andersson-Rolf, Amanda; Koo, Bon-Kyoung; Sasaki, Nobuo; Clevers, Hans

    2013-01-01

    Under previously developed culture conditions, mouse and human intestinal epithelia can be cultured and expanded over long periods. These so-called organoids recapitulate the three-dimensional architecture of the gut epithelium, and consist of all major intestinal cell types. One key advantage of these ex vivo cultures is their accessibility to live imaging. So far the establishment of transgenic fluorescent reporter organoids has required the generation of transgenic mice, a laborious and time-consuming process, which cannot be extended to human cultures. Here we present a transfection protocol that enables the generation of recombinant mouse and human reporter organoids using BAC (bacterial artificial chromosome) technology. PMID:24204693

  16. Production of homozygous transgenic rainbow trout with enhanced disease resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies conducted in our laboratory showed that transgenic medaka expressing cecropin B transgenes exhibited resistant characteristic to fish bacterial pathogens, Pseudomonas fluorescens and Vibrio anguillarum. To confirm whether antimicrobial peptide gene will also exhibit antibacterial an...

  17. Lectin cDNA and transgenic plants derived therefrom

    DOEpatents

    Raikhel, Natasha V.

    2000-10-03

    Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties.

  18. Delta Blues Scholarship and Imperialist Nostalgia.

    ERIC Educational Resources Information Center

    Nye, William P.

    When Delta blues are considered to be "folk music," the genre is inextricably tied to the neocolonial, sharecropping system of cotton production characteristic of the Mississippi Delta region between the Civil War and World War II. "Imperialist nostalgia," then, arises in accounts which pay primary and positive tribute to blues performances…

  19. The hepatitis delta virus and its infection

    SciTech Connect

    Rizzeto, M.; Gerin, J.L.; Purcell, R.H.

    1987-01-01

    This book contains over 50 papers. Some of the titles are: Structure and Replication of the Genome of Hepatitis Delta Virus; Clinical Significance of HDV RNA in HDV Disease; HBV DNA in Delta Chronic Carriers; Prevalance of HBV-DNA Among Anti-Hd Positive Patients; and Characterization of LKM/sub 1/ and LKM/sub 2/ Antigens.

  20. Electromagnetic excitation of the Delta(1232) resonance

    SciTech Connect

    V. Pascalutsa; M. Vanderhaeghen; Shin Nan Yang

    2006-09-05

    We review the description of the lowest-energy nucleon excitation--the Delta(1232)-resonance. Much of the recent effort has been focused on the precision measurements of the nucleon to Delta transition by means of electromagnetic probes. We review the results of those measurements and confront them with the state-of-the-art calculations based on chiral effective-field theories (EFT), lattice QCD, and QCD-inspired models. Some of the theoretical approaches are reviewed in detail. In particular, we describe the chiral EFT of QCD in the energy domain of the Delta-resonance, and its applications to the electromagnetic nucleon-to-Delta transition (gamma N Delta). We also describe the recent dynamical and unitary-isobar models of pion electroproduction which are extensively used in the extraction of the gamma* N Delta form factors from experiment. Furthermore, we discuss the link of the gamma* N Delta form factors to generalized parton distributions (GPDs), as well as the predictions of perturbative QCD for these transition form factors. The present status of understanding the Delta-resonance properties and the nature of its excitation is summarized.

  1. BAY DELTA CROSS CHANNEL OPERATIONAL STUDIES

    EPA Science Inventory

    The Delta Cross Channel was constructed in 1953 to deliver low-salinity water from the Sacramento River in Northern California to the South Delta where it is pumped to the San Francisco Bay Area and other parts of the State for public consumption and to the San Joaquin Valley for...

  2. Delta hepatitis: another concern for dentistry.

    PubMed

    Cottone, J A

    1986-01-01

    Delta hepatitis is a defective virus dependent on hepatitis B virus for replication and transmission. Delta hepatitis infection is becoming more prevalent in the United States, especially in parenteral drug abusers; several outbreaks have occurred. Infection control procedures and the hepatitis B vaccine can protect the dental staff from infection and transmission. PMID:3455994

  3. 27 CFR 9.96 - Mississippi Delta.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Mississippi Delta. 9.96 Section 9.96 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.96 Mississippi Delta. (a) Name. The name of...

  4. Production of homozygous transgenic rainbow trout with enhanced disease resistance.

    PubMed

    Chiou, Pinwen Peter; Chen, Maria J; Lin, Chun-Mean; Khoo, Jenny; Larson, Jon; Holt, Rich; Leong, Jo-Ann; Thorgarrd, Gary; Chen, Thomas T

    2014-06-01

    Previous studies conducted in our laboratory showed that transgenic medaka expressing cecropin B transgenes exhibited resistant characteristic to fish bacterial pathogens, Pseudomonas fluorescens and Vibrio anguillarum. To confirm whether antimicrobial peptide gene will also exhibit anti-bacterial and anti-viral characteristics in aquaculture important fish species, we produced transgenic rainbow trout expressing cecropin P1 or a synthetic cecropin B analog, CF-17, transgene by sperm-mediated gene transfer method. About 30 % of fish recovered from electroporation were shown to carry the transgene as determined by polymerase chain reaction (PCR) amplification assay. Positive P₁ transgenic fish were crossed to non-transgenic fish to establish F₁ transgenic founder families, and subsequently generating F₂, and F₃ progeny. Expression of cecropin P1 and CF-17 transgenes was detected in transgenic fish by reverse transcription (RT)-PCR analysis. The distribution of body sizes among F₁ transgenic fish were not significantly different from those of non-transgenic fish. Results of challenge studies revealed that many families of F₂ and F₃ transgenic fish exhibited resistance to infection by Aeromonas salmonicida and infectious hematopoietic necrosis virus (IHNV). All-male homozygous cecropin P1 transgenic families were produced by androgenesis from sperm of F₃ heterozygous transgenic fish in one generation. The resistant characteristic to A. salmonicida was confirmed in progeny derived from the outcross of all-male fish to non-transgenic females. Results of our current studies confirmed the possibility of producing disease-resistant homozygous rainbow trout strains by transgenesis of cecropin P1 or CF-17 gene and followed by androgenesis. PMID:24085608

  5. Delta-6 desaturase from borage converts linoleic acid to gamma-linolenic acid in HEK293 cells.

    PubMed

    Chen, Qing; Nimal, Jonathan; Li, Wanli; Liu, Xia; Cao, Wenguang

    2011-07-01

    Gamma-linolenic acid (GLA, 18:3 n6) is an essential polyunsaturated fatty acid of the omega-6 family and is found to be effective in prevention and/or treatment of various health problems. In this study, we evaluated the possibility of increasing γ-linolenic acid contents in mammalian cells using the delta-6 gene from Borago officinalis. The borage Δ6-desaturase gene (sDelta-6) was codon-optimized and introduced into HEK293 cells by lipofectin transfection. Co-expression of GFP with sDelta-6 and RT-PCR analysis indicated that sDelta-6 could be expressed in mammalian cells. Subsequently, the heterologous expression of borage Δ6-desaturase was evaluated by fatty acid analysis. Total cellular lipid analysis of transformed cells fed with linoleic acid (LA 18:2 n6) as a substrate showed that the expression of sDelta-6 resulted in an 228-483% (p<0.05) increase of GLA when compared with that in the control cells. The highest conversion efficiency of LA into GLA in sDelta-6(+) cells was 6.9 times higher than that in the control group (11.59% vs. 1.69%; p<0.05). Our present work demonstrated that the sDelta-6 gene from borage could be functionally expressed in mammalian cells, and could convert LA into GLA. Furthermore, this study may pave the way to generate transgenic livestock that can synthesise GLA. PMID:21679695

  6. Delta connected resonant snubber circuit

    DOEpatents

    Lai, J.S.; Peng, F.Z.; Young, R.W. Sr.; Ott, G.W. Jr.

    1998-01-20

    A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 36 figs.

  7. Delta connected resonant snubber circuit

    DOEpatents

    Lai, Jih-Sheng; Peng, Fang Zheng; Young, Sr., Robert W.; Ott, Jr., George W.

    1998-01-01

    A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.

  8. IDENTIFICATION OF ESCAPED TRANSGENIC CREEPING BENTGRASS IN OREGON

    EPA Science Inventory

    When transgenic plants are cultivated near wild species that are sexually compatible with the crop, gene flow between the crop and wild plants is possible. A resultant concern is that transgene flow and transgene introgression within wild populations could have unintended ecologi...

  9. Maize transgenes containing zein promoters are regulated by opaque2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenes have great potential in crop improvement, but relatively little is known about the epistatic interaction of transgenes with the native genes in the genome. Understanding these interactions is critical for predicting the response of transgenes to different genetic backgrounds and environm...

  10. 78 FR 53127 - Delta-Bienville Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-28

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Delta-Bienville Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. Date change. SUMMARY: The Delta-Bienville Resource Advisory...

  11. Monitoring transgenic plants using in vivo markers

    SciTech Connect

    Stewart, C.N. Jr.

    1996-06-01

    The gene coding for green fluorecent protein (GFP), isolated and cloned from the jellyfish Aequorea victoria, is an ideal transgene for the monitoring of any plant species. It has the ability to fluoresce without added substrate, enzyme, or cofactor; it does not introduce morphological or sexual aberrations when expressed. 7 refs., 1 fig.

  12. Transgenic plants with increased calcium stores

    NASA Technical Reports Server (NTRS)

    Wyatt, Sarah (Inventor); Tsou, Pei-Lan (Inventor); Robertson, Dominique (Inventor); Boss, Wendy (Inventor)

    2004-01-01

    The present invention provides transgenic plants over-expressing a transgene encoding a calcium-binding protein or peptide (CaBP). Preferably, the CaBP is a calcium storage protein and over-expression thereof does not have undue adverse effects on calcium homeostasis or biochemical pathways that are regulated by calcium. In preferred embodiments, the CaBP is calreticulin (CRT) or calsequestrin. In more preferred embodiments, the CaBP is the C-domain of CRT, a fragment of the C-domain, or multimers of the foregoing. In other preferred embodiments, the CaBP is localized to the endoplasmic reticulum by operatively associating the transgene encoding the CaBP with an endoplasmic reticulum localization peptide. Alternatively, the CaBP is targeted to any other sub-cellular compartment that permits the calcium to be stored in a form that is biologically available to the plant. Also provided are methods of producing plants with desirable phenotypic traits by transformation of the plant with a transgene encoding a CaBP. Such phenotypic traits include increased calcium storage, enhanced resistance to calcium-limiting conditions, enhanced growth and viability, increased disease and stress resistance, enhanced flower and fruit production, reduced senescence, and a decreased need for fertilizer production. Further provided are plants with enhanced nutritional value as human food or animal feed.

  13. Generation of Transgenic Rats Using Lentiviral Vectors.

    PubMed

    Reichardt, Holger M; Fischer, Henrike J

    2016-01-01

    Transgenesis is a valuable tool with which to study different aspects of gene function in the context of the intact organism. During the last two decades a tremendous number of transgenic animals have been generated, and the continuous improvement of technology and the development of new systems have fostered their widespread application in biomedical research. Generally, transgenic animals are generated by introducing foreign DNA into fertilized oocytes, which can be achieved either by injecting recombinant DNA into the pronucleus or by transferring lentiviral particles into the perivitelline space. While mice remain the favored species in many laboratories, there are a number of applications where the use of rats is advantageous. One such research area is multiple sclerosis. Here, several experimental models are available that are closely mimicking the human disease, and it is possible to induce neuroinflammation by transferring pathogenic T cells which can then be studied by flow cytometry and 2-photon live imaging. Unlike for mice, the development of transgenic rats has encountered some hurdles in the past, e.g., due to a complicated reproductive biology and the frailty of the fertilized oocytes in vitro. In this chapter we provide a protocol describing how we manipulate single cell embryos in our lab in order to efficiently generate transgenic rats in a variety of different strains using lentiviral gene transfer. PMID:25063498

  14. Transgenic Mouse Model of Chronic Beryllium Disease

    SciTech Connect

    Gordon, Terry

    2009-05-26

    Animal models provide powerful tools for dissecting dose-response relationships and pathogenic mechanisms and for testing new treatment paradigms. Mechanistic research on beryllium exposure-disease relationships is severely limited by a general inability to develop a sufficient chronic beryllium disease animal model. Discovery of the Human Leukocyte Antigen (HLA) - DPB1Glu69 genetic susceptibility component of chronic beryllium disease permitted the addition of this human beryllium antigen presentation molecule to an animal genome which may permit development of a better animal model for chronic beryllium disease. Using FVB/N inbred mice, Drs. Rubin and Zhu, successfully produced three strains of HLA-DPB1 Glu 69 transgenic mice. Each mouse strain contains a haplotype of the HLA-DPB1 Glu 69 gene that confers a different magnitude of odds ratio (OR) of risk for chronic beryllium disease: HLA-DPB1*0401 (OR = 0.2), HLA-DPB1*0201 (OR = 15), HLA-DPB1*1701 (OR = 240). In addition, Drs. Rubin and Zhu developed transgenic mice with the human CD4 gene to permit better transmission of signals between T cells and antigen presenting cells. This project has maintained the colonies of these transgenic mice and tested the functionality of the human transgenes.

  15. Metal resistance sequences and transgenic plants

    DOEpatents

    Meagher, Richard Brian; Summers, Anne O.; Rugh, Clayton L.

    1999-10-12

    The present invention provides nucleic acid sequences encoding a metal ion resistance protein, which are expressible in plant cells. The metal resistance protein provides for the enzymatic reduction of metal ions including but not limited to divalent Cu, divalent mercury, trivalent gold, divalent cadmium, lead ions and monovalent silver ions. Transgenic plants which express these coding sequences exhibit increased resistance to metal ions in the environment as compared with plants which have not been so genetically modified. Transgenic plants with improved resistance to organometals including alkylmercury compounds, among others, are provided by the further inclusion of plant-expressible organometal lyase coding sequences, as specifically exemplified by the plant-expressible merB coding sequence. Furthermore, these transgenic plants which have been genetically modified to express the metal resistance coding sequences of the present invention can participate in the bioremediation of metal contamination via the enzymatic reduction of metal ions. Transgenic plants resistant to organometals can further mediate remediation of organic metal compounds, for example, alkylmetal compounds including but not limited to methyl mercury, methyl lead compounds, methyl cadmium and methyl arsenic compounds, in the environment by causing the freeing of mercuric or other metal ions and the reduction of the ionic mercury or other metal ions to the less toxic elemental mercury or other metals.

  16. Transgenic plants protected from insect attack

    NASA Astrophysics Data System (ADS)

    Vaeck, Mark; Reynaerts, Arlette; Höfte, Herman; Jansens, Stefan; de Beuckeleer, Marc; Dean, Caroline; Zabeau, Marc; Montagu, Marc Van; Leemans, Jan

    1987-07-01

    The Gram-positive bacterium Bacillus thuringiensis produces proteins which are specifically toxic to a variety of insect species. Modified genes have been derived from bt2, a toxin gene cloned from one Bacillus strain. Transgenic tobacco plants expressing these genes synthesize insecticidal proteins which protect them from feeding damage by larvae of the tobacco hornworm.

  17. Effect of transgene number of spontaneous and radiation-induced micronuclei in lacl transgenic mice

    SciTech Connect

    O`Loughlin, K.G.; Hamer, J.D.; Winegar, R.A.; Mirsalis, J.C.; Short, J.M.

    1994-12-31

    Lacl transgenic mice are widely used for the measurement of mutations in specific target issues. The lacl transgene is present in mice as 40 tandem repeats; this sequence is homozygous (contained in both copies of chromosome 5) in C57Bl/6 mice, and is hemizygous in B6C3F1 mice. Previous reports have indicated that tandem repeats can produce chromosome instability, fragile sites, and other effects. To determine whether the presence of the transgene effects micronucleus induction we compared the response of nontransgenic (NTR) to hemizygous (HEMI) transgenic B6C3F1 mice and to hemizygous and homozygous (HOMO) transgenic C57Bl/6 mice. Five mice/group were irradiated with 500 cGy from a {sup 137}Cs source. Bone marrow was harvested 24 hr after treatment and 2000 polychromatic erythrocytes (PCE) were analyzed per animal. The presence or absence of the lacl transgene had no effect in unirradiated mice on the percent of micronucleated PCE (MN) or on the ratio of PCE to total red blood cells for either strain: B6C3F1 mice had MN frequencies of 0.26% and 0.20% for NTR and HEMI mice, respectively; C57Bl/6 mice had MN frequencies of 0.34%, 0.32%, and 0.38% for NTR, HEMI, and HOMO mice, respectively. Radiation-induced micronucleus frequencies were significantly higher in HEMI lacl B6C3F1 mice (2.85%) than in NTR litter mates (1.59%); the converse was true in C57Bl/6 mice: NTR were 2.45%, HEMI were 1.25%, HOMO were 1.65%. These data suggest that the lacl transgene does not cause chromosome instability as measured by spontaneous micronucleus levels. However, the response of these transgenic mice to a variety of clastogenic agents needs to be investigated before they are integrated into standard in vivo assays for chromosome damage.

  18. TransgeneOmics - A transgenic platform for protein localization based function exploration.

    PubMed

    Hasse, Susanne; Hyman, Anthony A; Sarov, Mihail

    2016-03-01

    The localization of a protein is intrinsically linked to its role in the structural and functional organization of the cell. Advances in transgenic technology have streamlined the use of protein localization as a function discovery tool. Here we review the use of large genomic DNA constructs such as bacterial artificial chromosomes as a transgenic platform for systematic tag-based protein function exploration. PMID:26475212

  19. Influence of different organic fertilizers on quality parameters and the delta(15)N, delta(13)C, delta(2)H, delta(34)S, and delta(18)O values of orange fruit (Citrus sinensis L. Osbeck).

    PubMed

    Rapisarda, Paolo; Camin, Federica; Fabroni, Simona; Perini, Matteo; Torrisi, Biagio; Intrigliolo, Francesco

    2010-03-24

    To investigate the influence of different types of fertilizers on quality parameters, N-containing compounds, and the delta(15)N, delta(13)C, delta(2)H, delta (34)S, and delta(18)O values of citrus fruit, a study was performed on the orange fruit cv. 'Valencia late' (Citrus sinensis L. Osbeck), which was harvested in four plots (three organic and one conventional) located on the same farm. The results demonstrated that different types of organic fertilizers containing the same amount of nitrogen did not effect important changes in orange fruit quality parameters. The levels of total N and N-containing compounds such as synephrine in fruit juice were not statistically different among the different treatments. The delta(15)N values of orange fruit grown under fertilizer derived from animal origin as well as from vegetable compost were statistically higher than those grown with mineral fertilizer. Therefore, delta(15)N values can be used as an indicator of citrus fertilization management (organic or conventional), because even when applied organic fertilizers are of different origins, the natural abundance of (15)N in organic citrus fruit remains higher than in conventional ones. These treatments also did not effect differences in the delta(13)C, delta(2)H, delta(34)S, and delta(18)O values of fruit. PMID:20184327

  20. Skin human papillomavirus type 38 alters p53 functions by accumulation of deltaNp73.

    PubMed

    Accardi, Rosita; Dong, Wen; Smet, Anouk; Cui, Rutao; Hautefeuille, Agnes; Gabet, Anne-Sophie; Sylla, Bakary S; Gissmann, Lutz; Hainaut, Pierre; Tommasino, Massimo

    2006-03-01

    The E6 and E7 of the cutaneous human papillomavirus (HPV) type 38 immortalize primary human keratinocytes, an event normally associated with the inactivation of pathways controlled by the tumour suppressor p53. Here, we show for the first time that HPV38 alters p53 functions. Expression of HPV38 E6 and E7 in human keratinocytes or in the skin of transgenic mice induces stabilization of wild-type p53. This selectively activates the transcription of deltaNp73, an isoform of the p53-related protein p73, which in turn inhibits the capacity of p53 to induce the transcription of genes involved in growth suppression and apoptosis. DeltaNp73 downregulation by an antisense oligonucleotide leads to transcriptional re-activation of p53-regulated genes and apoptosis. Our findings illustrate a novel mechanism of the alteration of p53 function that is mediated by a cutaneous HPV type and support the role of HPV38 and deltaNp73 in human carcinogenesis. PMID:16397624

  1. Making BAC transgene constructs with lambda-red recombineering system for transgenic animals or cell lines.

    PubMed

    Holmes, Scott; Lyman, Suzanne; Hsu, Jen-Kang; Cheng, JrGang

    2015-01-01

    The genomic DNA libraries based on Bacteria Artificial Chromosomes (BAC) are the foundation of whole genomic mapping, sequencing, and annotation for many species like mice and humans. With their large insert size, BACs harbor the gene-of-interest and nearby transcriptional regulatory elements necessary to direct the expression of the gene-of-interest in a temporal and cell-type specific manner. When replacing a gene-of-interest with a transgene in vivo, the transgene can be expressed with the same patterns and machinery as that of the endogenous gene. This chapter describes in detail a method of using lambda-red recombineering to make BAC transgene constructs with the integration of a transgene into a designated location within a BAC. As the final BAC construct will be used for transfection in cell lines or making transgenic animals, specific considerations with BAC transgenes such as genotyping, BAC coverage and integrity as well as quality of BAC DNA will be addressed. Not only does this approach provide a practical and effective way to modify large DNA constructs, the same recombineering principles can apply to smaller high copy plasmids as well as to chromosome engineering. PMID:25239742

  2. Can Transgenic Maize Affect Soil Microbial Communities?

    PubMed Central

    Mulder, Christian; Wouterse, Marja; Raubuch, Markus; Roelofs, Willem; Rutgers, Michiel

    2006-01-01

    The aim of the experiment was to determine if temporal variations of belowground activity reflect the influence of the Cry1Ab protein from transgenic maize on soil bacteria and, hence, on a regulatory change of the microbial community (ability to metabolize sources belonging to different chemical guilds) and/or a change in numerical abundance of their cells. Litter placement is known for its strong influence on the soil decomposer communities. The effects of the addition of crop residues on respiration and catabolic activities of the bacterial community were examined in microcosm experiments. Four cultivars of Zea mays L. of two different isolines (each one including the conventional crop and its Bacillus thuringiensis cultivar) and one control of bulk soil were included in the experimental design. The growth models suggest a dichotomy between soils amended with either conventional or transgenic maize residues. The Cry1Ab protein appeared to influence the composition of the microbial community. The highly enhanced soil respiration observed during the first 72 h after the addition of Bt-maize residues can be interpreted as being related to the presence of the transgenic crop residues. This result was confirmed by agar plate counting, as the averages of the colony-forming units of soils in conventional treatments were about one-third of those treated with transgenic straw. Furthermore, the addition of Bt-maize appeared to induce increased microbial consumption of carbohydrates in BIOLOG EcoPlates. Three weeks after the addition of maize residues to the soils, no differences between the consumption rate of specific chemical guilds by bacteria in soils amended with transgenic maize and bacteria in soils amended with conventional maize were detectable. Reaped crop residues, comparable to post-harvest maize straw (a common practice in current agriculture), rapidly influence the soil bacterial cells at a functional level. Overall, these data support the existence of short

  3. Can transgenic maize affect soil microbial communities?

    PubMed

    Mulder, Christian; Wouterse, Marja; Raubuch, Markus; Roelofs, Willem; Rutgers, Michiel

    2006-09-29

    The aim of the experiment was to determine if temporal variations of belowground activity reflect the influence of the Cry1Ab protein from transgenic maize on soil bacteria and, hence, on a regulatory change of the microbial community (ability to metabolize sources belonging to different chemical guilds) and/or a change in numerical abundance of their cells. Litter placement is known for its strong influence on the soil decomposer communities. The effects of the addition of crop residues on respiration and catabolic activities of the bacterial community were examined in microcosm experiments. Four cultivars of Zea mays L. of two different isolines (each one including the conventional crop and its Bacillus thuringiensis cultivar) and one control of bulk soil were included in the experimental design. The growth models suggest a dichotomy between soils amended with either conventional or transgenic maize residues. The Cry1Ab protein appeared to influence the composition of the microbial community. The highly enhanced soil respiration observed during the first 72 h after the addition of Bt-maize residues can be interpreted as being related to the presence of the transgenic crop residues. This result was confirmed by agar plate counting, as the averages of the colony-forming units of soils in conventional treatments were about one-third of those treated with transgenic straw. Furthermore, the addition of Bt-maize appeared to induce increased microbial consumption of carbohydrates in BIOLOG EcoPlates. Three weeks after the addition of maize residues to the soils, no differences between the consumption rate of specific chemical guilds by bacteria in soils amended with transgenic maize and bacteria in soils amended with conventional maize were detectable. Reaped crop residues, comparable to post-harvest maize straw (a common practice in current agriculture), rapidly influence the soil bacterial cells at a functional level. Overall, these data support the existence of short

  4. [Animal welfare problems concerning the use of transgenic animals

    PubMed

    Mani, Peter

    1998-01-01

    Using transgenic animals as clinical models pose certain problems since they can suffer. Yet in single cases transgenic animals can reduce the suffering of (other) animals. The permission to generate transgenic animals is not yet clearly regulated in Switzerland. The term "dignity of creature", as formulated in the Swiss Constitution, has to be defined for the Swiss animal protection law. We present the recommendations of the commission for ethical questions concerning transgenic animals appointed by the Federal Council. Partly, these recommendations shall also be applied to the traditional breeding methods. We support the nomination of a national ethics committee for transgenic animals. PMID:11208267

  5. Online high-precision delta(2)H and delta(18)O analysis in water by pyrolysis.

    PubMed

    Lu, Feng H

    2009-10-01

    A method for online simultaneous delta(2)H and delta(18)O analysis in water by high-temperature conversion is presented. Water is injected by using a syringe into a high-temperature carbon reactor and converted into H(2) and CO, which are separated by gas chromatography (GC) and carried by helium to the isotope ratio mass spectrometer for hydrogen and oxygen isotope analysis. A series of experiments was conducted to evaluate several issues such as sample size, temperature and memory effects. The delta(2)H and delta(18)O values in multiple water standards changed consistently as the reactor temperature increased from 1150 to 1480 degrees C. The delta(18)O in water can be measured at a lower temperature (e.g. 1150 degrees C) although the precision was relatively poor at temperatures <1300 degrees C. Memory effects exist for delta(2)H and delta(18)O between two waters, and can be reduced (to <1%) with proper measures. The injection of different amounts of water may affect the isotope ratio results. For example, in contrast to small injections (100 nL or less) from small syringes (e.g. 1.2 microL), large injections (1 microL or more) from larger syringes (e.g. 10 microL) with dilution produced asymmetric peaks and shifts of isotope ratios, e.g. 4 per thousand for delta(2)H and 0.4 per thousand for delta(18)O, probably resulting from isotope fractionation during dilution via the ConFlo interface. This method can be used to analyze nanoliter samples of water (e.g. 30 nL) with good precision of 0.5 per thousand for delta(2)H and 0.1 per thousand for delta(18)O. This is important for geosciences; for instance, fluid inclusions in ancient minerals may be analyzed for delta(2)H and delta(18)O to help understand the formation environments. PMID:19714707

  6. Identifying hazards associated with lava deltas

    NASA Astrophysics Data System (ADS)

    Poland, Michael P.; Orr, Tim R.

    2014-12-01

    Lava deltas, formed where lava enters the ocean and builds a shelf of new land extending from the coastline, represent a significant local hazard, especially on populated ocean island volcanoes. Such structures are unstable and prone to collapse—events that are often accompanied by small explosions that can deposit boulders and cobbles hundreds of meters inland. Explosions that coincide with collapses of the East Lae `Apuki lava delta at Kīlauea Volcano, Hawai`i, during 2005-2007 followed an evolutionary progression mirroring that of the delta itself. A collapse that occurred when the lava-ocean entry was active was associated with a blast of lithic blocks and dispersal of spatter and fine, glassy tephra. Shortly after delta growth ceased, a collapse exposed hot rock to cold ocean water, resulting in an explosion composed entirely of lithic blocks and lapilli. Further collapse of the delta after several months of inactivity, by which time it had cooled significantly, resulted in no recognizable explosion deposit. Seaward displacement and subsidence of the coastline immediately inland of the delta was measured by both satellite and ground-based sensors and occurred at rates of several centimeters per month even after the lava-ocean entry had ceased. The anomalous deformation ended only after complete collapse of the delta. Monitoring of ground deformation may therefore provide an indication of the potential for delta collapse, while the hazard associated with collapse can be inferred from the level of activity, or the time since the last activity, on the delta.

  7. Identifying hazards associated with lava deltas

    USGS Publications Warehouse

    Poland, Michael P.; Orr, Tim R.

    2014-01-01

    Lava deltas, formed where lava enters the ocean and builds a shelf of new land extending from the coastline, represent a significant local hazard, especially on populated ocean island volcanoes. Such structures are unstable and prone to collapse—events that are often accompanied by small explosions that can deposit boulders and cobbles hundreds of meters inland. Explosions that coincide with collapses of the East Lae ‘Apuki lava delta at Kīlauea Volcano, Hawai‘i, during 2005–2007 followed an evolutionary progression mirroring that of the delta itself. A collapse that occurred when the lava–ocean entry was active was associated with a blast of lithic blocks and dispersal of spatter and fine, glassy tephra. Shortly after delta growth ceased, a collapse exposed hot rock to cold ocean water, resulting in an explosion composed entirely of lithic blocks and lapilli. Further collapse of the delta after several months of inactivity, by which time it had cooled significantly, resulted in no recognizable explosion deposit. Seaward displacement and subsidence of the coastline immediately inland of the delta was measured by both satellite and ground-based sensors and occurred at rates of several centimeters per month even after the lava–ocean entry had ceased. The anomalous deformation ended only after complete collapse of the delta. Monitoring of ground deformation may therefore provide an indication of the potential for delta collapse, while the hazard associated with collapse can be inferred from the level of activity, or the time since the last activity, on the delta.

  8. Efficient Generation of Mice with Consistent Transgene Expression by FEEST.

    PubMed

    Gao, Lei; Jiang, Yonghua; Mu, Libing; Liu, Yanbin; Wang, Fengchao; Wang, Peng; Zhang, Aiqun; Tang, Nan; Chen, Ting; Luo, Minmin; Yu, Lei; Gao, Shaorong; Chen, Liang

    2015-01-01

    Transgenic mouse models are widely used in biomedical research; however, current techniques for producing transgenic mice are limited due to the unpredictable nature of transgene expression. Here, we report a novel, highly efficient technique for the generation of transgenic mice with single-copy integration of the transgene and guaranteed expression of the gene-of-interest (GOI). We refer to this technique as functionally enriched ES cell transgenics, or FEEST. ES cells harboring an inducible Cre gene enabled the efficient selection of transgenic ES cell clones using hygromycin before Cre-mediated recombination. Expression of the GOI was confirmed by assaying for the GFP after Cre recombination. As a proof-of-principle, we produced a transgenic mouse line containing Cre-activatable tTA (cl-tTA6). This tTA mouse model was able to induce tumor formation when crossed with a transgenic mouse line containing a doxycycline-inducible oncogene. We also showed that the cl-tTA6 mouse is a valuable tool for faithfully recapitulating the clinical course of tumor development. We showed that FEEST can be easily adapted for other genes by preparing a transgenic mouse model of conditionally activatable EGFR L858R. Thus, FEEST is a technique with the potential to generate transgenic mouse models at a genome-wide scale. PMID:26573149

  9. N and. delta. resonances: an experimental review

    SciTech Connect

    Kelly, R.L.

    1980-07-01

    Experimental progress in N and ..delta.. resonances since the Oxford baryon conference is reviewed. The review concentrates on hadronic channels, and on developments of the last one or two years. The topics reviewed include the antiproton lifetime; the ..delta../sup + +/ magnetic moment; measurements of ..pi..N elastic and charge-exchange scattering in the ..delta.. region, the eta n threshold region, and the high-mass region; partial wave analyses of ..pi..N ..-->.. ..pi..N; measurements of two-body inelastic ..pi..N scattering; and isobar analyses of ..pi..N ..-->.. ..pi pi..N. 75 references, 3 figures, 4 tables.

  10. Changes in hepatic gene expression related to innate immunity, growth and iron metabolism in GH-transgenic amago salmon (Oncorhynchus masou) by cDNA subtraction and microarray analysis, and serum lysozyme activity.

    PubMed

    Mori, Tsukasa; Hiraka, Ikuei; Kurata, Youichi; Kawachi, Hiroko; Mano, Nobuhiro; Devlin, Robert H; Nagoya, Hiroyuki; Araki, Kazuo

    2007-03-01

    Growth hormone (GH) transgenic amago salmon (Oncorhynchus masou) were generated with a construct containing the sockeye salmon GH1 gene fused to the metallothionein-B (MT-B) promoter from the same species. This transgene directed significant growth enhancement with transgenic fish reaching approximately four to five times greater weight than control salmon in F(2) and F(3) generations. This drastic growth enhancement by GH transgene is well known in fish species compared with mammals, however, such fish can show morphological abnormalities and physiological disorders like other GH transgenic animals. GH is known to have many acute effects, but currently there are no data describing the chronic effects of over-expression of GH on various hepatic genes in GH transgenic fish. Hepatic gene expression is anticipated to play very important roles in many physiological functions and growth performance of transgenic and control salmon. To examine these effects, we performed subtractive hybridization (using cDNA generated from liver RNA) in both directions to identify genes both increased and decreased in transgenic salmon relative to controls (576 clones were isolated and sequenced in total). Heme oxygenase, vitelline envelope protein, Acyl-coA binding protein, NADH dehydrogenase, mannose binding lectin-associated serine protease, hemopexin-like protein, leucyte-derived chemotaxin2 (LECT2), and many other genes were obtained in higher clone frequencies suggesting enhanced expression. In contrast, complement C3-1, lectin, rabin, alcohol dehydrogenase, Tc1-like transposase, Delta6-desaturase, and pentraxin genes were obtained in lower frequencies. Microarray analysis was also performed to obtain quantitative expression data for these subtracted cDNA clones. Analysis of fish across seasons was also conducted using both F(2) and F(3) salmon. Results of the microarray data essentially corresponded with those of the subtraction data when both F(2) and F(3) fish were completely

  11. Regeneration of transgenic cassava from transformed embryogenic tissues.

    PubMed

    Zhang, Peng; Puonti-Kaerlas, Johanna

    2005-01-01

    Production of transgenic plants is gradually becoming routine in cassava biotechnology. Green cotyledons of maturing somatic embryos (somatic cotyledons for short) and friable embryogenic suspensions (FES) are the target tissues for transformation by Agrobacterium or biolistics. Putative transgenic shoots develop from transformed somatic cotyledons via shoot organogenesis or from FES via somatic embryogenesis under selection. Maturation of transgenic somatic embryos is induced by transfer to maturation medium with reduced concentrations of selective agents. Mature somatic embryos can also develop directly from FES cells under selection. Transgenic plants are regenerated by the elongation of transgenic shootlets from organogenesis experiments and by the germination of or shoot development from transgenic mature embryos cultured without selection. beta-Glucuronidase (GUS) assays and rooting tests can be used to screen for escapes from selection, which improves the regeneration rate of truly transgenic plants. PMID:15310920

  12. Niger Delta play types, Nigeria

    SciTech Connect

    Akinpelu, A.O.

    1995-08-01

    Exploration databases can be more valuable when sorted by play type. Play specific databases provide a system to organize E & P data used in evaluating the range of values of parameters for reserve estimation and risk assessment. It is important both in focusing the knowledge base and in orienting research effort. A play in this context is any unique combination of trap, reservoir and source properties with the right dynamics of migration and preservation that results in hydrocarbon accumulation. This definitions helps us to discriminate the subtle differences found with these accumulation settings. About 20 play types were identified around the Niger Delta oil province in Nigeria. These are grouped into three parts: (1) The proven plays-constituting the bulk of exploration prospects in Nigeria today. (2) The unproven or semi-proven plays usually with some successes recorded in a few tries but where knowledge is still inadequate. (3) The unproven or analogous play concept. These are untested but geologically sound ideas which may or may not have been tried elsewhere. With classification and sub grouping of these play types into specific databases, intrinsic attributes and uniqueness of each of them with respect to the four major risk elements and the eight parameters for reserve estimation can be better understood.

  13. Upper Wilcox Rosita delta system of south Texas: growth-faulted shelf-edge deltas

    SciTech Connect

    Edwards, M.B.

    1981-01-01

    The Rosita delta system, a heretofore unrecognized, major depositional system preserved in the deep upper Wilcox of south Texas, was delineated by detailed correlation of approximately 500 well logs. The Rosita delta system comprises at least three delta complexes, each of which can be traced up to tens of miles along strike and up to approximately 15 mi (24 km) downdip. Basinward, across the growth-fault zone, each delta complex thickens from about 600 ft (180 m) to more than 3000 ft (900 m). The growth faults were activated by progradation of deltas over unstable prodelta-slope muds at the contemporary shelf margin. The three upper Wilcox delta complexes studied in detail are, from oldest to youngest, the Duval, Zapata, and Live Oak deltas, named for the counties in which they are centered. Each complex consists of several lobes, some of which can be traced across the deep zones where the thickness increases by as much as tenfold owing to progradation over active growth faults. Characteristic coarsening-upward progradational units are interpreted from electric log patterns to include prodelta shales, delta-front sandstones, distributary channel and channel-mouth bar sandstones, and interdistributary shales and sandstones. Appreciable variability in sandstone distribution in the deltas may reflect changing importance of fluvial versus marine currents in distributing sediment along the delta front. However, all of the deltas prograded abruptly toward the shelf margin. The gulfward extent of these delta complexes is unknown, and it is concluded that appreciable quantities of sandstone remain to be explored in the deep subsurface of the trend.

  14. Damped Oscillator with Delta-Kicked Frequency

    NASA Technical Reports Server (NTRS)

    Manko, O. V.

    1996-01-01

    Exact solutions of the Schrodinger equation for quantum damped oscillator subject to frequency delta-kick describing squeezed states are obtained. The cases of strong, intermediate, and weak damping are investigated.

  15. Delta-nucleus dynamics: proceedings of symposium

    SciTech Connect

    Lee, T.S.H.; Geesaman, D.F.; Schiffer, J.P.

    1983-10-01

    The appreciation of the role in nuclear physics of the first excited state of the nucleon, the delta ..delta..(1232), has grown rapidly in the past decade. The delta resonance dominates nuclear reactions induced by intermediate energy pions, nucleons, and electromagnetic probes. It is also the most important non-nucleonic degree of freedom needed to resolve many fundamental problems encountered in the study of low-energy nuclear phenomena. Clearly, a new phase of nuclear physics has emerged and conventional thinking must be extended to account for this new dimension of nuclear dynamics. The most challenging problem we are facing is how a unified theory can be developed to describe ..delta..-nucleus dynamics at all energies. In exploring this new direction, it is important to have direct discussions among researchers with different viewpoints. Separate entries were prepared for the 49 papers presented. (WHK)

  16. [The return of the hepatitis delta virus].

    PubMed

    Zoutendijk, R; de Jonge, P J F; de Man, R A

    2016-01-01

    - There are several regions worldwide with a high prevalence of infection with the hepatitis delta virus (HDV) in hepatitis B virus (HBV) carriers.- Chronic HDV infection is occurring with increasing frequency due to increased immigration.- HDV transmission can take place through the same routes as HBV by simultaneous infection with both viruses (co-infection) or infection of an HBV carrier with HDV (superinfection).- Delta hepatitis is considered as the most severe form of viral hepatitis with a high risk of progression to cirrhosis and hepatocellular carcinoma.- Chronic delta hepatitis is exclusively observed in patients who are HBV carriers.- Pegylated interferon is currently the only registered therapy for patients with delta hepatitis, but leads to a persistent virological response in only a minority of them, and rarely leads to a complete cure.- New antivirals, such as viral entry blockers, prenylation inhibitors and anti-sense oligonucleotides are promising and currently being investigated in phase 2 trials. PMID:27405575

  17. Delta XTE Launch Activities (Scrub #2)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This NASA Kennedy Space Center video presents Delta XTE (X-Ray Timing Explorer) launch activities on 12/11/95. The launch was rescheduled for next weekend due to out of limit upper level wind conditions.

  18. Beteigeuze (Alpha Orionis) und Mintaka (Delta Orionis)

    NASA Astrophysics Data System (ADS)

    Vollmann, Wolfgang

    2013-02-01

    Magnitude measures transformed to Johnson V of Alpha Orionis (Betelgeuse) and Delta Orionis with a wide-angle lens and DSLR are presented and discussed. Alpha Orionis light changes are shown clearly. The primary and secondary eclipses of Delta Orionis with amplitudes of 0.12 and 0.05 mag respectively are clearly recorded. They occur near phase 0.00 and 0.50 respectively of current elements from VSX (2).

  19. Migration in Vulnerable Deltas: A Research Strategy

    NASA Astrophysics Data System (ADS)

    Hutton, C.; Nicholls, R. J.; Allan, A.

    2015-12-01

    C. Hutton1, & R. J. Nicholls1, , 1 University of Southampton, University Road, Southampton, Hampshire, United Kingdom, SO17 1BJ. cwh@geodata. soton.ac.ukAbstractGlobally, deltas contain 500 million people and with rising sea levels often linked to large number of forced migrants are expected in the coming century. However, migration is already a major process in deltas, such as the growth of major cities such as Dhaka and Kolkata. Climate and environmental change interacts with a range of catchment and delta level drivers, which encompass a nexus of sea-level rise, storms, freshwater and sediment supply from the catchment, land degradation, subsidence, agricultural loss and socio-economic stresses. DECCMA (Deltas, Vulnerability and Climate Change: Migration and Adaptation/CARRIA) is investigating migration in the Ganges-Brahmaputra-Meghna (GBM), Mahanadi and Volta Deltas, including the influence of climate change. The research will explore migration from a range of perspectives including governance and stakeholder analysis, demographic analysis, household surveys of sending and receiving areas, macro-economic analysis, and hazards and hotspot analysis both historically and into the future. Migration under climate change will depend on other adaptation in the deltas and this will be examined. Collectively, integrated analysis will be developed to examine migration, other adaptation and development pathways with a particular focus on the implications for the poorest. This will require the development of input scenarios, including expert-derived exogenous scenarios (e.g., climate change) and endogenous scenarios of the delta developed in a participatory manner. This applied research will facilitate decision support methods for the development of deltas under climate change, with a focus on migration and other adaptation strategies.

  20. Transgenic farm animals: present and future.

    PubMed

    Niemann, H; Kues, W; Carnwath, J W

    2005-04-01

    Until recently, pronuclear microinjection of deoxyribonucleic acid (DNA) was the standard method for producing transgenic animals. This technique is now being replaced by more efficient protocols based on somatic nucleartransferthat also permit targeted genetic modifications. Lentiviral vectors and small interfering ribonucleic acid technology are also becoming important tools for transgenesis. Transgenic farm animals are important in human medicine as sources of biologically active proteins, as donors in xenotransplantation, and for research in cell and gene therapy. Typical agricultural applications include improved carcass composition, lactational performance and wool production, as well as enhanced disease resistance and reduced environmental impact. Product safety can be ensured by standardisation of procedures and monitored by polymerase chain reaction and array technology. As sequence information and genomic maps of farm animals are refined, it becomes increasingly practical to remove or modify individual genes. This approach to animal breeding will be instrumental in meeting global challenges in agricultural production in the future. PMID:16110896

  1. Preparing Nimbus E on Delta Vehicle

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Nimbus E, the sixth spacecraft in the Nimbus series, is shown preparing for launch on December 12, 1972 from the Western Test Range (WTR), Space Launch Complex SLC-2, West, by the Thrust- Augmented Delta vehicle. The satellite was placed in an 1100-kilometer run-synchronous nearly circular polar orbit. The spacecraft was designated Nimbus 5 upon confirmation that it had achieved successful orbit. The Delta launch vehicle family started development in 1959. The Delta is composed of parts from the Thor, an intermediate-range ballistic missile, as its first stage, and the Vanguard as its second. The first Delta was launched from Cape Canaveral on May 13, 1960 and was powerful enough to deliver a 100-pound spacecraft into geostationary transfer orbit. Delta has been used to launch civil, commercial, and military satellites into orbit. For more information about Delta, please see Chapter 3 in Roger Launius and Dennis Jenkins' book To Reach the High Frontier published by The University Press of Kentucky in 2002.

  2. Lena River delta formation during the Holocene

    NASA Astrophysics Data System (ADS)

    Bolshiyanov, D.; Makarov, A.; Savelieva, L.

    2015-01-01

    The Lena River delta, the largest delta of the Arctic Ocean, differs from other deltas because it consists mainly of organomineral sediments, commonly called peat, that contain a huge organic carbon reservoir. The analysis of delta sediment radiocarbon ages showed that they could not have formed as peat during floodplain bogging; rather, they accumulated when Laptev Sea water level was high and green mosses and sedges grew and were deposited on the surface of flooded marshes. The Lena River delta formed as organomineral masses and layered sediments accumulated during transgressive phases when sea level rose. In regressive phases, the islands composed of these sediments and other, more ancient islands were eroded. Each new sea transgression led to further accumulation of layered sediments. As a result of alternating transgressive and regressive phases, the first alluvial-marine terrace formed, consisting of geological bodies of different ages. Determining the formation age of different areas of the first terrace and other marine terraces on the coast allowed the periods of increasing (8000-6000 BP (years before present), 4500-4000, 2500-1500, and 400-200 BP) and decreasing (5000, 3000, and 500 BP) Laptev Sea levels to be distinguished in the Lena Delta area.

  3. Lena River Delta formation during the Holocene

    NASA Astrophysics Data System (ADS)

    Bolshiyanov, D.; Makarov, A.; Savelieva, L.

    2014-03-01

    The Lena River Delta, the largest delta of the Arctic Ocean, differs from other deltas because it consists mainly of organomineral sediments, commonly called peat, that contain a huge organic carbon reservoir. The analysis of Delta sediment radiocarbon ages showed that they could not have formed as peat during floodplain bogging, but accumulated when Laptev Sea water level was high and green mosses and sedges grew and were deposited on the surface of flooded marshes. The Lena River Delta formed as organomineral masses and layered sediments accumulated during transgressive phases when sea level rose. In regressive phases, the islands composed of these sediments and other, more ancient islands were eroded. Each new sea transgression led to further accumulation of layered sediments. As a result of alternating transgressive and regressive phases the first alluvial-marine terrace formed, consisting of geological bodies of different ages. Determining the formation age of different areas of the first terrace and other marine terraces on the coast allowed the periods of increasing (8-6 Ka, 4.5-4 Ka, 2.5-1.5 Ka, 0.4-0.2 Ka) and decreasing (5 Ka, 3 Ka, 0.5 Ka) Laptev Sea levels to be distinguished in the Lena Delta area.

  4. River deltas: channelizing sandpiles with memory

    NASA Astrophysics Data System (ADS)

    Jerolmack, Douglas; Reitz, Meredith

    2013-03-01

    River deltas are wedges of sediment that are built via the lateral migration of self-channelizing rivers, but the timescale of this process is prohibitively long to observe in nature. Here we present laboratory results that allow us to examine how channels form and fill space to create a delta. Flow collapses into a single channel whose dimensions adjust to threshold transport conditions for the imposed sediment load. This channelization causes localized shoreline growth until the slope drops below a threshold value for sediment transport. This leads to deposition within the channel, with an upstream-migrating step akin to a stopping front in granular flows, which causes widespread flooding and the selection of a new (steeper) channel path. This cycle is remarkably periodic; delta slope oscillates between two thresholds - entrainment and distrainment - analogous to static and dynamic angles of repose. Selection of a new flow path is inherently stochastic, but previously abandoned channels act as significant attractors for the flow. Once a critical density of flow paths has been established, the flow oscillates among the same 3-5 channels indefinitely. These dynamics result in self-similar (quasi-)radial growth of delta lobes, which can be described using a simple geometric model. Despite its simplicity, the experimental system agrees well with what can be measured from natural deltas Thus, temporal and spatial patterns of deltas appear to be a robust result of mass conservation and transport thresholds.

  5. Delta's role in reaching the fourth environment

    NASA Technical Reports Server (NTRS)

    Grimes, D. W.; Ganoung, J. K.

    1981-01-01

    The Delta launch vehicle has played a significant role in spaceand airborne studies since its first launch in 1960, and a high volume period of service is planned for the 1980s. The historical role played by Delta in launching satellites from 1960 to the present is discussed, and vehicle modifications made during this period are summarized. It is shown that out of 154 launches, 143 proved successful for an overall reliability of 93%. The forecasted launch schedule through 1985 is also presented. Various modifications are now under way to provide spacecraft interchangeability with the Shuttle: a Payload Assist Module (PAM) is proposed to provide an orderly transition from the Delta expendable vehicle to the Shuttle reusable vehicle; the new Delta 3920 Improved Second Stage is the result of a need for improved Delta performance to meet 3910 payload capabilities; the firing sequence of the solid rocket motors was altered from five at liftoff and four during ascent to a sequence of six and three, thereby increasing spacecraft weight in geosynchronous transfer orbit. Potential future improvements discussed include the Delta 4920, 9-ft-diam fairing, booster engine performance, PAM solid motor performance, a universal second stage, a hydrogen-oxygen second stage, and large strap-on solids.

  6. An ovine transgenic Huntington's disease model

    PubMed Central

    Jacobsen, Jessie C.; Bawden, C. Simon; Rudiger, Skye R.; McLaughlan, Clive J.; Reid, Suzanne J.; Waldvogel, Henry J.; MacDonald, Marcy E.; Gusella, James F.; Walker, Simon K.; Kelly, Jennifer M.; Webb, Graham C.; Faull, Richard L.M.; Rees, Mark I.; Snell, Russell G.

    2010-01-01

    Huntington's disease (HD) is an inherited autosomal dominant neurodegenerative disorder caused by an expansion of a CAG trinucleotide repeat in the huntingtin (HTT) gene [Huntington's Disease Collaborative Research Group (1993) A novel gene containing a trinucleotide repeat that is expanded and unstable on Huntington's disease chromosomes. The Huntington's Disease Collaborative Research Group. Cell, 72, 971–983]. Despite identification of the gene in 1993, the underlying life-long disease process and effective treatments to prevent or delay it remain elusive. In an effort to fast-track treatment strategies for HD into clinical trials, we have developed a new large-animal HD transgenic ovine model. Sheep, Ovis aries L., were selected because the developmental pattern of the ovine basal ganglia and cortex (the regions primarily affected in HD) is similar to the analogous regions of the human brain. Microinjection of a full-length human HTT cDNA containing 73 polyglutamine repeats under the control of the human promotor resulted in six transgenic founders varying in copy number of the transgene. Analysis of offspring (at 1 and 7 months of age) from one of the founders showed robust expression of the full-length human HTT protein in both CNS and non-CNS tissue. Further, preliminary immunohistochemical analysis demonstrated the organization of the caudate nucleus and putamen and revealed decreased expression of medium size spiny neuron marker DARPP-32 at 7 months of age. It is anticipated that this novel transgenic animal will represent a practical model for drug/clinical trials and surgical interventions especially aimed at delaying or preventing HD initiation. New sequence accession number for ovine HTT mRNA: FJ457100. PMID:20154343

  7. Transgenic Analysis of GFAP Promoter Elements

    PubMed Central

    Yeo, Sujeong; Bandyopadhyay, Susanta; Messing, Albee; Brenner, Michael

    2015-01-01

    Transcriptional regulation of the glial fibrillary acidic protein gene (GFAP) is of interest because of its astrocyte specificity and its upregulation in response to CNS injuries. We have used a transgenic approach instead of cell transfection to identify promoter elements of the human GFAP gene, since previous observations show that GFAP transcription is regulated differently in transfected cultured cells from in the mouse. We previously showed that block mutation of enhancer regions spanning from bp −1488 to −1434 (the C1.1 segment) and −1443 to −1399 (C1.2) resulted in altered patterns of expression and loss of astrocyte specificity, respectively. This analysis has now been extended upstream to bp −1612 to −1489 (the B region), which previously has been shown especially important for expression. Block mutation of each of four contiguous sequences, which together span the B region, each decreased the level of transgene activity by at least 50%, indicating that multiple sites contribute to the transcriptional activity in a cooperative manner. Several of the block mutations also altered the brain region pattern of expression, astrocyte specificity and/or the developmental time course. Transgenes were then analyzed in which mutations were limited to specific transcription factor binding sites in each of the 4 B block segments as well as in C1.1 and C1.2. Whereas mutation of the conserved consensus AP-1 site unexpectedly had little effect on transgene expression; NFI, SP1, STAT3, and NF-κB were identified as having important roles in regulating the strength of GFAP promoter activity and/or its astrocyte specificity. PMID:23832770

  8. Predictive imaging of chemotherapeutic response in a transgenic mouse model of pancreatic cancer.

    PubMed

    Wang, Ping; Yoo, Byunghee; Sherman, Sarah; Mukherjee, Pinku; Ross, Alana; Pantazopoulos, Pamela; Petkova, Victoria; Farrar, Christian; Medarova, Zdravka; Moore, Anna

    2016-08-01

    The underglycosylated mucin 1 tumor antigen (uMUC1) is a biomarker that forecasts the progression of adenocarcinomas. In this study, we evaluated the utility of a dual-modality molecular imaging approach based on targeting uMUC1 for monitoring chemotherapeutic response in a transgenic murine model of pancreatic cancer (KCM triple transgenic mice). An uMUC1-specific contrast agent (MN-EPPT) was synthesized for use with magnetic resonance imaging (MRI) and fluorescence optical imaging. It consisted of dextran-coated iron oxide nanoparticles conjugated to the near infrared fluorescent dye Cy5.5 and to a uMUC1-specific peptide (EPPT). KCM triple transgenic mice were given gemcitabine as chemotherapy while control animals received saline injections following the same schedule. Changes in uMUC1 levels following chemotherapy were monitored using T2-weighted MRI and optical imaging before and 24 hr after injection of the MN-EPPT. uMUC1 expression in tumors from both groups was evaluated by histology and qRT-PCR. We observed that the average delta-T2 in the gemcitabine-treated group was significantly reduced compared to the control group indicating lower accumulation of MN-EPPT, and correspondingly, a lower level of uMUC1 expression. In vivo optical imaging confirmed the MRI findings. Fluorescence microscopy of pancreatic tumor sections showed a lower level of uMUC1 expression in the gemcitabine-treated group compared to the control, which was confirmed by qRT-PCR. Our data proved that changes in uMUC1 expression after gemcitabine chemotherapy could be evaluated using MN-EPPT-enhanced in vivo MR and optical imaging. These results suggest that the uMUC1-targeted imaging approach could provide a useful tool for the predictive assessment of therapeutic response. PMID:26996122

  9. Studies of an expanded trinucleotide repeat in transgenic mice

    SciTech Connect

    Bingham, P.; Wang, S.; Merry, D.

    1994-09-01

    Spinal and bulbar muscular atrophy (SBMA) is a progressive motor neuron disease caused by expansion of a trinucleotide repeat in the androgen receptor gene (AR{sup exp}). AR{sup exp} repeats expand further or contract in approximately 25% of transmissions. Analogous {open_quotes}dynamic mutations{close_quotes} have been reported in other expanded trinucleotide repeat disorders. We have been developing a mouse model of this disease using a transgenic approach. Expression of the SBMA AR was documented in transgenic mice with an inducible promoter. No phenotypic effects of transgene expression were observed. We have extended our previous results on stability of the expanded trinucleotide repeat in transgenic mice in two lines carrying AR{sup exp}. Tail DNA was amplified by PCR using primers spanning the repeat on 60 AR{sup exp} transgenic mice from four different transgenic lines. Migration of the PCR product through an acrylamide gel showed no change of the 45 CAG repeat length in any progeny. Similarly, PCR products from 23 normal repeat transgenics showed no change from the repeat length of the original construct. Unlike the disease allele in humans, the expanded repeat AR cDNA in transgenic mice showed no change in repeat length with transmission. The relative stability of CAG repeats seen in the transgenic mice may indicate either differences in the fidelity of replicative enzymes, or differences in error identification and repair between mice and humans. Integration site or structural properties of the transgene itself might also play a role.

  10. Transgenic oil palm: production and projection.

    PubMed

    Parveez, G K; Masri, M M; Zainal, A; Majid, N A; Yunus, A M; Fadilah, H H; Rasid, O; Cheah, S C

    2000-12-01

    Oil palm is an important economic crop for Malaysia. Genetic engineering could be applied to produce transgenic oil palms with high value-added fatty acids and novel products to ensure the sustainability of the palm oil industry. Establishment of a reliable transformation and regeneration system is essential for genetic engineering. Biolistic was initially chosen as the method for oil palm transformation as it has been the most successful method for monocotyledons to date. Optimization of physical and biological parameters, including testing of promoters and selective agents, was carried out as a prerequisite for stable transformation. This has resulted in the successful transfer of reporter genes into oil palm and the regeneration of transgenic oil palm, thus making it possible to improve the oil palm through genetic engineering. Besides application of the Biolistics method, studies on transformation mediated by Agrobacterium and utilization of the green fluorescent protein gene as a selectable marker gene have been initiated. Upon the development of a reliable transformation system, a number of useful targets are being projected for oil palm improvement. Among these targets are high-oleate and high-stearate oils, and the production of industrial feedstock such as biodegradable plastics. The efforts in oil palm genetic engineering are thus not targeted as commodity palm oil. Due to the long life cycle of the palm and the time taken to regenerate plants in tissue culture, it is envisaged that commercial planting of transgenic palms will not occur any earlier than the year 2020. PMID:11171275

  11. Transgenic approaches to western corn rootworm control.

    PubMed

    Narva, Kenneth E; Siegfried, Blair D; Storer, Nicholas P

    2013-01-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) is a significant corn pest throughout the United States corn belt. Rootworm larvae feed on corn roots causing yield losses and control expenditures that are estimated to exceed US$1 billion annually. Traditional management practices to control rootworms such as chemical insecticides or crop rotation have suffered reduced effectiveness due to the development of physiological and behavioral resistance. Transgenic maize expressing insecticidal proteins are very successful in protecting against rootworm damage and preserving corn yield potential. However, the high rate of grower adoption and early reliance on hybrids expressing a single mode of action and low-dose traits threatens the durability of commercialized transgenic rootworm technology for rootworm control. A summary of current transgenic approaches for rootworm control and the corresponding insect resistance management practices is included. An overview of potential new modes of action based on insecticidal proteins, and especially RNAi targeting mRNA coding for essential insect proteins is provided. PMID:23604211

  12. Generation of cyanogen-free transgenic cassava.

    PubMed

    Siritunga, Dimuth; Sayre, Richard T

    2003-07-01

    Cassava ( Manihot esculenta Crantz.) is the major source of calories for subsistence farmers in sub-Saharan Africa. Cassava, however, contains potentially toxic levels of the cyanogenic glucoside, linamarin. The cyanogen content of cassava foods can be reduced to safe levels by maceration, soaking, rinsing and baking; however, short-cut processing techniques can yield toxic food products. Our objective was to eliminate cyanogens from cassava so as to eliminate the need for food processing. To achieve this goal we generated transgenic acyanogenic cassava plants in which the expression of the cytochrome P450 genes ( CYP79D1 and CYP79D2), that catalyze the first-dedicated step in linamarin synthesis, was inhibited. Using a leaf-specific promoter to drive the antisense expression of the CYP79D1/ CYP79D2 genes we observed up to a 94% reduction in leaf linamarin content associated with an inhibition of CYP79D1 and CYP79D2 expression. Importantly, the linamarin content of roots also was reduced by 99% in transgenic plants having between 60 and 94% reduction in leaf linamarin content. Analysis of CYP79D1/ CYP79D2 transcript levels in transgenic roots indicated they were unchanged relative to wild-type plants. These results suggest that linamarin is transported from leaves to roots and that a threshold level of leaf linamarin production is required for transport. PMID:14520563

  13. Using empirical data to model transgene dispersal.

    PubMed Central

    Meagher, T R; Belanger, F C; Day, P R

    2003-01-01

    One element of the current public debate about genetically modified crops is that gene flow from transgenic cultivars into surrounding weed populations will lead to more problematic weeds, particularly for traits such as herbicide resistance. Evolutionary biologists can inform this debate by providing accurate estimates of gene flow potential and subsequent ecological performance of resulting hybrids. We develop a model for gene flow incorporating exponential distance and directional effects to be applied to windpollinated species. This model is applied to previously published data on gene flow in experimental plots of Agrostis stolonifera L. (creeping bentgrass), which assessed gene flow from transgenic plants resistant to the herbicide glufosinate to surrounding non-transgenic plants. Our results show that although pollen dispersal can be limited in some sites, it may be extensive in others, depending on local conditions such as exposure to wind. Thus, hybridization under field conditions is likely to occur. Given the nature of the herbicide resistance trait, we regard this trait as unlikely to persist in the absence of herbicide, and suggest that the ecological consequences of such gene flow are likely to be minimal. PMID:12831482

  14. A novel mouse PKC{delta} splice variant, PKC{delta}IX, inhibits etoposide-induced apoptosis

    SciTech Connect

    Kim, Jung D.; Seo, Kwang W.; Lee, Eun A.; Quang, Nguyen N.; Cho, Hong R.; Kwon, Byungsuk

    2011-07-01

    Highlights: {yields} A novel PKC{delta} isoform, named PKC{delta}IX, that lacks the C1 domain and the ATP-binding site is ubiquitously expressed. {yields} PKC{delta}IX inhibits etoposide-induced apoptosis. {yields} PKC{delta}IX may function as an endogenous dominant negative isoform for PKC{delta}. -- Abstract: Protein kinase C (PKC) {delta} plays an important role in cellular proliferation and apoptosis. The catalytic fragment of PKC{delta} generated by caspase-dependent cleavage is essential for the initiation of etoposide-induced apoptosis. In this study, we identified a novel mouse PKC{delta} isoform named PKC{delta}IX (Genebank Accession No. (HQ840432)). PKC{delta}IX is generated by alternative splicing and is ubiquitously expressed, as seen in its full-length PKC{delta}. PKC{delta}IX lacks the C1 domain, the caspase 3 cleavage site, and the ATP binding site but preserves an almost intact c-terminal catalytic domain and a nuclear localization signal (NLS). The structural characteristics of PKC{delta}IX provided a possibility that this PKC{delta} isozyme functions as a novel dominant-negative form for PKC{delta} due to its lack of the ATP-binding domain that is required for the kinase activity of PKC{delta}. Indeed, overexpression of PKC{delta}IX significantly inhibited etoposide-induced apoptosis in NIH3T3 cells. In addition, an in vitro kinase assay showed that recombinant PKC{delta}IX protein could competitively inhibit the kinase activity of PKC{delta}. We conclude that PKC{delta}IX can function as a natural dominant-negative inhibitor of PKC{delta}in vivo.

  15. The Okavango: Whose Delta is it?

    NASA Astrophysics Data System (ADS)

    Magole, Lapologang; Magole, Lefatshe Innocent

    The Okavango Delta is amongst the largest Ramsar sites ( http://www.ramsar.org/sitelist.pdf) in the world and an important wetland for community livelihoods, conservation and tourism in Botswana. Over the years, the utilization of the delta has shifted from communal use to state control, with an increased use for conservation and tourism. This increased use for conservation and tourism has manifested in the physical expansion of the conservation area - Moremi Game Reserve and the formation of Wildlife Management Areas (WMAs) around the reserve, whose primary land use is wildlife utilization. The expansion of the conservation area has translated into several practical matters, including expansion of the area for non-hunting activities or photographic areas. The livelihoods of local communities of the Okavango delta who depended on fishing, hunter-gathering, livestock rearing, rain-fed agriculture and flood recession farming have been negatively affected by the expansion of conservation and tourism in the delta. The livelihoods alternatives in the form of Community Based Natural Resource Management (CBNRM) and tourism have not provided substitutes for the people as the communities are still reliant on the same old livelihood sources as in the past, albeit within smaller and restricted areas. This paper explores the ownership of the natural resources within the Okavango Delta. It asks and attempts to answer the following questions: Who owns and controls the use of the land? Who has access to other resources there in? Who makes the decisions on how the delta resources should be managed and used? Who benefits from the delta resources? We argue firstly that ownership of the delta as defined by legal parameters and demonstrated in natural resource management practice is vested on government. Secondly, government, after assuming ownership of the delta continues to sell its stake to the international community, at the expense of local ownership and access to resources. We

  16. Expression of complete metabolic pathways in transgenic plants.

    PubMed

    Krichevsky, Alexander; Zaltsman, Adi; King, Lisa; Citovsky, Vitaly

    2012-01-01

    Plant genetic engineering emerged as a methodology to introduce only few transgenes into the plant genome. Following fast-paced developments of the past few decades, engineering of much larger numbers of transgenes became a reality, allowing to introduce full metabolic pathways from other organisms into plants and generate transgenics with startling new traits. From the advent of the classical plant genetic engineering, the transgenes were introduced into the nuclear genome of the plant cell, and this strategy still is quite successful when applied to few transgenes. However, for introducing large number of transgenes, we advocate that the chloroplast genome is a superior choice, especially for engineering of new complete metabolic pathways into plants. The ability to genetically engineer plants with complex and fully functional metabolic pathways from other organisms bears a substantial promise in generation of pharmaceuticals, i.e., biopharming, and new agricultural crops with that traits never existed before, leading to enhancement in quality of human life. PMID:22616478

  17. Efficient production of germline transgenic chickens using lentiviral vectors.

    PubMed

    McGrew, Michael J; Sherman, Adrian; Ellard, Fiona M; Lillico, Simon G; Gilhooley, Hazel J; Kingsman, Alan J; Mitrophanous, Kyriacos A; Sang, Helen

    2004-07-01

    An effective method for genetic modification of chickens has yet to be developed. An efficient technology, enabling production of transgenic birds at high frequency and with reliable expression of transgenes, will have many applications, both in basic research and in biotechnology. We investigated the efficiency with which lentiviral vectors could transduce the chicken germ line and examined the expression of introduced reporter transgenes. Ten founder cockerels transmitted the vector to between 4% and 45% of their offspring and stable transmission to the G2 generation was demonstrated. Analysis of expression of reporter gene constructs in several transgenic lines showed a conserved expression profile between individuals that was maintained after transmission through the germ line. These data demonstrate that lentiviral vectors can be used to generate transgenic lines with an efficiency in the order of 100-fold higher than any previously published method, with no detectable silencing of transgene expression between generations. PMID:15192698

  18. Efficient production of germline transgenic chickens using lentiviral vectors

    PubMed Central

    McGrew, Michael J; Sherman, Adrian; Ellard, Fiona M; Lillico, Simon G; Gilhooley, Hazel J; Kingsman, Alan J; Mitrophanous, Kyriacos A; Sang, Helen

    2004-01-01

    An effective method for genetic modification of chickens has yet to be developed. An efficient technology, enabling production of transgenic birds at high frequency and with reliable expression of transgenes, will have many applications, both in basic research and in biotechnology. We investigated the efficiency with which lentiviral vectors could transduce the chicken germ line and examined the expression of introduced reporter transgenes. Ten founder cockerels transmitted the vector to between 4% and 45% of their offspring and stable transmission to the G2 generation was demonstrated. Analysis of expression of reporter gene constructs in several transgenic lines showed a conserved expression profile between individuals that was maintained after transmission through the germ line. These data demonstrate that lentiviral vectors can be used to generate transgenic lines with an efficiency in the order of 100-fold higher than any previously published method, with no detectable silencing of transgene expression between generations. PMID:15192698

  19. A model for the Delta(1600) resonance and gamma N -> Delta(1600) transition

    SciTech Connect

    G. Ramalho, K. Tsushima

    2010-10-01

    A covariant spectator constituent quark model is applied to study the gamma N -> Delta(1600) transition. Two processes are important in the transition: a photon couples to the individual quarks of the Delta(1600) core (quark core), and a photon couples to the intermediate pion-baryon states (pion cloud). While the quark core contributions are estimated assuming Delta(1600) as the first radial excitation of Delta(1232), the pion cloud contributions are estimated based on an analogy with the gamma N -> Delta(1232) transition. To estimate the pion cloud contributions in the gamma N -> Delta(1600) transition, we include the relevant intermediate states, pi-N, pi-Delta, pi-N(1440) and pi-Delta(1600). Dependence on the four-momentum transfer squared, Q2, is predicted for the magnetic dipole transition form factor, GM*(Q2), as well as the helicity amplitudes, A_1/2(Q2) and A_3/2(Q2). The results at Q2=0 are compared with the existing data.

  20. Model for the {Delta}(1600) resonance and {gamma}N{yields}{Delta}(1600) transition

    SciTech Connect

    Ramalho, G.; Tsushima, K.

    2010-10-01

    A covariant spectator constituent quark model is applied to study the {gamma}N{yields}{Delta}(1600) transition. Two processes are important in the transition: a photon couples to the individual quarks of the {Delta}(1600) core (quark core), and a photon couples to the intermediate pion-baryon states (pion cloud). While the quark core contributions are estimated assuming {Delta}(1600) as the first radial excitation of {Delta}(1232), the pion cloud contributions are estimated based on an analogy with the {gamma}N{yields}{Delta}(1232) transition. To estimate the pion cloud contributions in the {gamma}N{yields}{Delta}(1600) transition, we include the relevant intermediate states, {pi}N, {pi}{Delta}, {pi}N(1440) and {pi}{Delta}(1600). Dependence on the four-momentum transfer squared, Q{sup 2}, is predicted for the magnetic dipole transition form factor, G{sub M}*(Q{sup 2}), as well as the helicity amplitudes, A{sub 1/2}(Q{sup 2}) and A{sub 3/2}(Q{sup 2}). The results at Q{sup 2}=0 are compared with the existing data.

  1. Using metabolomics to estimate unintended effects in transgenic crop plants: problems, promises and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenic crops are widespread in some countries and sectors of the agro-economy, but are also highly contentious. Proponents of transgenic crop improvement often cite the “substantial equivalence” of transgenic crops to their non-transgenic parents and sibling varieties. Opponents of transgenic cr...

  2. Transgenic apple (Malus x domestica) shoot showing low browning potential.

    PubMed

    Murata, M; Haruta, M; Murai, N; Tanikawa, N; Nishimura, M; Homma, S; Itoh, Y

    2000-11-01

    Transgenic apple shoots were prepared from leaf disks by using Agrobacterium tumefaciens carrying the kanamycin (KM) resistance gene and antisense polyphenol oxidase (PPO) DNA. Four transgenic apple lines that grew on the medium containing 50 microgram/mL KM were obtained. They contained the KM resistance gene and grew stably on the medium for >3 years. Two transgenic shoot lines containing antisense PPO DNA in which PPO activity was repressed showed a lower browning potential than a control shoot. PMID:11087467

  3. The DELTA MONSTER: An RPV designed to investigate the aerodynamics of a delta wing platform

    NASA Technical Reports Server (NTRS)

    Connolly, Kristen; Flynn, Mike; Gallagher, Randy; Greek, Chris; Kozlowski, Marc; Mcdonald, Brian; Mckenna, Matt; Sellar, Rich; Shearon, Andy

    1989-01-01

    The mission requirements for the performance of aerodynamic tests on a delta wind planform posed some problems, these include aerodynamic interference; structural support; data acquisition and transmission instrumentation; aircraft stability and control; and propulsion implementation. To eliminate the problems of wall interference, free stream turbulence, and the difficulty of achieving dynamic similarity between the test and actual flight aircraft that are associated with aerodynamic testing in wind tunnels, the concept of the remotely piloted vehicle which can perform a basic aerodynamic study on a delta wing was the main objective for the Green Mission - the Delta Monster. The basic aerodynamic studies were performed on a delta wing with a sweep angle greater than 45 degrees. These tests were performed at various angles of attack and Reynolds numbers. The delta wing was instrumented to determine the primary leading edge vortex formation and location, using pressure measurements and/or flow visualization. A data acquisition system was provided to collect all necessary data.

  4. Holocene evolution of a wave-dominated fan-delta: Godavari delta, India

    NASA Astrophysics Data System (ADS)

    Saito, Y.; Nageswara Rao, K.; Nagakumar, K.; Demudu, G.; Rajawat, A.; Kubo, S.; Li, Z.

    2013-12-01

    The Godavari delta is one of the world's largest wave-dominated deltas. The Godavari River arises in the Western Ghats near the west coast of India and drains an area of about 3.1x10^5 km^2, flowing about 1465 km southeast across the Indian peninsula to the Bay of Bengal. The Godavari delta consists of a gentle seaward slope from its apex (12 m elevation) at Rajahmundry and a coastal beach-ridge plain over a distance of about 75 km and covers ~5200 km^2 as a delta plain. The river splits into two major distributary channels, the Gautami and the Vasishta, at a barrage constructed in the mid-1800s. The coastal environment of the deltaic coast is microtidal (~1 m mean tidal range) and wave-dominated (~1.5 m mean wave height in the June-September SW monsoon season, ~0.8 m in the NE monsoon season). Models of the Holocene evolution of the Godavari delta have changed from a zonal progradation model (e.g. Nageswara Rao & Sadakata, 1993) to a truncated cuspate delta model (Nageswara Rao et al., 2005, 2012). Twelve borehole cores (340 m total length), taken in the coastal delta plain during 2010-2013, yielded more than 100 C-14 dates. Sediment facies and C-14 dates from these and previous cores and remote-sensing data support a new delta evolution model. The Holocene coastal delta plain is divided into two parts by a set of linear beach ridges 12-14 km landward from the present shoreline in the central part of the delta. The location of the main depocenter (lobe) has shifted during the Holocene from 1) the center to 2) the west, 3) east, 4) center, 5) west, and 6) east. The linear beach ridges separate the first three from the last three stages. These lobe shifts are controlled by river channel shifts near the apex. Just as the current linear shoreline of the central part of the delta and the concave-up nearshore topography are the result of coastal erosion of a cuspate delta, the linear beach ridges indicate a former eroded shoreline. An unconformity within the deltaic

  5. [Effects of transgenic crops on soil microorganisms: a review].

    PubMed

    Zhang, Yan-Jun; Xie, Ming; Peng, De-Liang

    2013-09-01

    The worldwide cultivation of transgenic crops not only provides tremendous economic benefits, but also induces the concern about the potential risks of transgenic crops on soil ecosystem in which microorganisms are involved. The potential effects of transgenic crops on soil microorganisms include the direct effects of the transgenic proteins on non-target soil microorganisms, and the indirect effects of the unintentional changes in the chemical compositions of root exudates induced by the introduction of the exogenous transgenic proteins. Most of the studies on transgenic crops suggested that transgenic crops could affect the quantity and structure of soil microbial populations. However, the perceivable effects on the soil microorganisms are inconsistent, with some in significant and others in non-significant, or some with persistent and others with non-persistent. This paper summarized the effects of different transgenic crops on soil microorganisms, and discussed the factors affecting the assessment reliability, including the species of transgenic crops and the experimental technologies and principles. Some issues needed to be paid special attention to in the future studies were put forward. PMID:24417130

  6. Hepatic steatosis in transgenic mice overexpressing human histone deacetylase 1

    SciTech Connect

    Wang, Ai-Guo; Seo, Sang-Beom; Moon, Hyung-Bae; Shin, Hye-Jun; Kim, Dong Hoon; Kim, Jin-Man; Lee, Tae-Hoon; Kwon, Ho Jeong; Yu, Dae-Yeul . E-mail: dyyu10@kribb.re.kr; Lee, Dong-Seok . E-mail: lee10@kribb.re.kr

    2005-05-06

    It is generally thought that histone deacetylases (HDACs) play important roles in the transcriptional regulation of genes. However, little information is available concerning the specific functions of individual HDACs in disease states. In this study, two transgenic mice lines were established which harbored the human HDAC1 gene. Overexpressed HDAC1 was detected in the nuclei of transgenic liver cells, and HDAC1 enzymatic activity was significantly higher in the transgenic mice than in control littermates. The HDAC1 transgenic mice exhibited a high incidence of hepatic steatosis and nuclear pleomorphism. Molecular studies showed that HDAC1 may contribute to nuclear pleomorphism through the p53/p21 signaling pathway.

  7. {delta}-mediated pion production in nuclei

    SciTech Connect

    Praet, C.; Lalakulich, O.; Jachowicz, N.; Ryckebusch, J.

    2009-04-15

    We present a fully relativistic formalism for describing neutrino-induced {delta}-mediated single-pion production in nuclei. We assess the ambiguities stemming from the {delta} interactions and quantify the uncertainties in the axial form-factor parameters by comparing with the available bubble-chamber neutrino-scattering data. To include nuclear effects, we turn to a relativistic plane-wave impulse approximation (RPWIA) using realistic bound-state wave functions derived in the Hartree approximation to the {sigma}-{omega} Walecka model. For neutrino energies larger than 1 GeV, we show that a relativistic Fermi-gas model with appropriate binding-energy correction produces results that are comparable to the RPWIA that naturally includes Fermi motion, nuclear-binding effects, and the Pauli exclusion principle. Including {delta} medium modifications roughly halves the RPWIA cross section. Calculations for primary (prior to undergoing final-state interactions) pion production are presented for both electron- and neutrino-induced processes, and a comparison with electron-scattering data and other theoretical approaches is included. We infer that the total {delta}-production strength is underestimated by about 20 to 25%, a fraction that is due to the pionless decay modes of the {delta} in a medium. The model presented in this work can be naturally extended to include the effect of final-state interactions in a relativistic and quantum-mechanical way.

  8. Tracking Nile Delta vulnerability to Holocene change.

    PubMed

    Marriner, Nick; Flaux, Clément; Morhange, Christophe; Stanley, Jean-Daniel

    2013-01-01

    Understanding deltaic resilience in the face of Holocene climate change and human impacts is an important challenge for the earth sciences in characterizing the full range of present and future wetland responses to global warming. Here, we report an 8000-year mass balance record from the Nile Delta to reconstruct when and how this sedimentary basin has responded to past hydrological shifts. In a global Holocene context, the long-term decrease in Nile Delta accretion rates is consistent with insolation-driven changes in the 'monsoon pacemaker', attested throughout the mid-latitude tropics. Following the early to mid-Holocene growth of the Nile's deltaic plain, sediment losses and pronounced erosion are first recorded after ~4000 years ago, the corollaries of falling sediment supply and an intensification of anthropogenic impacts from the Pharaonic period onwards. Against the backcloth of the Saharan 'depeopling', reduced river flow underpinned by a weakening of monsoonal precipitation appears to have been particularly conducive to the expansion of human activities on the delta by exposing productive floodplain lands for occupation and irrigation agriculture. The reconstruction suggests that the Nile Delta has a particularly long history of vulnerability to extreme events (e.g. floods and storms) and sea-level rise, although the present sediment-starved system does not have a direct Holocene analogue. This study highlights the importance of the world's deltas as sensitive archives to investigate Holocene geosystem responses to climate change, risks and hazards, and societal interaction. PMID:23922692

  9. Delta Coherence Protocols: The Home Update Protocol

    SciTech Connect

    Williams, C.; Reynolds, P.F.; de Supinoki, B.

    2000-07-21

    We describe a new class of directory coherence protocols called delta coherence protocols that use network guarantees to support a new and highly concurrent approach to maintain a consistent shared memory. Delta coherence protocols are more concurrent than other coherence protocols in that they allow processes to pipeline memory accesses without violating sequential consistency; support multiple concurrent readers and writers to the same cache block; and allow processes to access multiple shared variables atomically without invalidating the copies held by other processes or otherwise obtaining exclusive access to the referenced variables. Delta protocols include both update and invalidate protocols. In this paper we describe the simplest, most basic delta protocol, an update protocol called the home update protocol. Delta protocols are based on isotach network guarantees. An isotach network maintains a logical time system that allows each process to predict and control the logical time at which its messages are received. Processes use isotach guarantees to control the logical time at which their requests on shared memory appear to be executed. We prove the home update protocol is correct using logical time to reason about the order in which requests are executed.

  10. Using LC-MS Based Methods for Testing the Digestibility of a Nonpurified Transgenic Membrane Protein in Simulated Gastric Fluid.

    PubMed

    Skinner, Wayne S; Phinney, Brett S; Herren, Anthony; Goodstal, Floyd J; Dicely, Isabel; Facciotti, Daniel

    2016-06-29

    The digestibility of a nonpurified transgenic membrane protein was determined in pepsin, as part of the food safety evaluation of its resistance to digestion and allergenic potential. Delta-6-desaturase from Saprolegnia diclina, a transmembrane protein expressed in safflower for the production of gamma linolenic acid in the seed, could not be obtained in a pure, native form as normally required for this assay. As a novel approach, the endoplasmic reticulum isolated from immature seeds was digested in simulated gastric fluid (SGF) and the degradation of delta-6-desaturase was selectively followed by SDS-PAGE and targeted LC-MS/MS quantification using stable isotope-labeled peptides as internal standards. The digestion of delta-6-desaturase by SGF was shown to be both rapid and complete. Less than 10% of the initial amount of D6D remained intact after 30 s, and no fragments large enough (>3 kDa) to elicit a type I allergenic response remained after 60 min. PMID:27255301