964 resultados para 2-nitrocinnamic acid
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BACKGROUND: The use of valproic acid in the first trimester of pregnancy is associated with an increased risk of spina bifida, but data on the risks of other congenital malformations are limited. METHODS: We first combined data from eight published cohort studies (1565 pregnancies in which the women were exposed to valproic acid, among which 118 major malformations were observed) and identified 14 malformations that were significantly more common among the offspring of women who had received valproic acid during the first trimester. We then assessed the associations between use of valproic acid during the first trimester and these 14 malformations by performing a case-control study with the use of the European Surveillance of Congenital Anomalies (EUROCAT) antiepileptic-study database, which is derived from population-based congenital-anomaly registries. Registrations (i.e., pregnancy outcomes with malformations included in EUROCAT) with any of these 14 malformations were compared with two control groups, one consisting of infants with malformations not previously linked to valproic acid use (control group 1), and one consisting of infants with chromosomal abnormalities (control group 2). The data set included 98,075 live births, stillbirths, or terminations with malformations among 3.8 million births in 14 European countries from 1995 through 2005. RESULTS: Exposure to valproic acid monotherapy was recorded for a total of 180 registrations, with 122 registrations in the case group, 45 in control group 1, and 13 in control group 2. As compared with no use of an antiepileptic drug during the first trimester (control group 1), use of valproic acid monotherapy was associated with significantly increased risks for 6 of the 14 malformations under consideration; the adjusted odds ratios were as follows: spina bifida, 12.7 (95% confidence interval [CI], 7.7 to 20.7); atrial septal defect, 2.5 (95% CI, 1.4 to 4.4); cleft palate, 5.2 (95% CI, 2.8 to 9.9); hypospadias, 4.8 (95% CI, 2.9 to 8.1); polydactyly, 2.2 (95% CI, 1.0 to 4.5); and craniosynostosis, 6.8 (95% CI, 1.8 to 18.8). Results for exposure to valproic acid were similar to results for exposure to other antiepileptic drugs. CONCLUSIONS: The use of valproic acid monotherapy in the first trimester was associated with significantly increased risks of several congenital malformations, as compared with no use of antiepileptic drugs or with use of other antiepileptic drugs.
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The tumor Ag SSX-2 (HOM-MEL-40) was found by serological identification of Ags by recombinant expression cloning and was shown to be a cancer/testis Ag expressed in a wide variety of tumors. It may therefore represent a source of CD8(+) T cell epitopes useful for specific immunotherapy of cancer. To identify potential SSX-2-derived epitopes that can be recognized by CD8(+) T cells, we used an approach that combined: 1) the in vitro proteasomal digestion of precursor peptides overlapping the complete SSX-2 sequence; 2) the prediction of SSX-2-derived peptides with an appropriate HLA-A2 binding score; and 3) the analysis of a tumor-infiltrated lymph node cell population from an HLA-A2(+) melanoma patient with detectable anti-SSX-2 serum Abs. This strategy allowed us to identify peptide SSX-2(41-49) as an HLA-A2-restricted epitope. SSX2(41-49)-specific CD8(+) T cells were readily detectable in the tumor-infiltrated lymph node population by multimer staining, and CTL clones isolated by multimer-guided cell sorting were able to lyse HLA-A2(+) tumor cells expressing SSX-2.
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The CD8 molecule is a glycoprotein expressed on a subset of mature T lymphocytes. It has been postulated to be a receptor for class I major histocompatibility complex molecules. In the mouse, CD8 is a heterodimer composed of Ly-2 and Ly-3 chains. We have isolated and analyzed cDNA and cosmid clones corresponding to the Ly-3 subunit. One of the isolated, cosmid clones was subsequently transfected, alone or in combination with the Ly-2 gene, into mouse Ltk- cells. Analysis of the Ly-2,3 molecules expressed at the surface of the double transfectants indicated that they are serologically and biochemically indistinguishable from their normal counterparts expressed on lymphoid cells. Ltk- cells transfected with the Ly-2 gene alone were shown to react with a subset of anti-CD8 monoclonal antibodies whereas Ly-3 transfectants did not stain with any of the anti-Ly-3 antibodies employed in this study. Since at least one of these antibodies (53-5.8) has been previously shown to recognize an epitope which is retained on the Ly-3 subunit after dissociation of the heterodimeric Ly-2,3 complex, these observations suggest that the expression of the Ly-2 polypeptide is required to permit the detectable cell surface expression of the antigenic determinants carried by the Ly-3 subunit.
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To gain further insight into abscisic acid (ABA) signaling and its role in growth regulation, we have screened for Arabidopsis (Arabidopsis thaliana) mutants hypersensitive to ABA-mediated root growth inhibition. As a result, we have identified a loss-of-function allele of BREVIS RADIX (BRX) in the Columbia background, named brx-2, which shows enhanced response to ABA-mediated inhibition of root growth. BRX encodes a key regulator of cell proliferation and elongation in the root, which has been implicated in the brassinosteroid (BR) pathway as well as in the regulation of auxin-responsive gene expression. Mutants affected in BR signaling that are not impaired in root growth, such as bes1-D, bzr1-D, and bsu1-D, also showed enhanced sensitivity to ABA-mediated inhibition of root growth. Triple loss-of-function mutants affected in PP2Cs, which act as negative regulators of ABA signaling, showed impaired root growth in the absence of exogenous ABA, indicating that disturbed regulation of ABA sensitivity impairs root growth. In agreement with this result, diminishing ABA sensitivity of brx-2 by crossing it with a 35S:HAB1 ABA-insensitive line allowed significantly higher recovery of root growth after brassinolide treatment. Finally, transcriptomic analysis revealed that ABA treatment negatively affects auxin signaling in wild-type and brx-2 roots and that ABA response is globally altered in brx-2. Taken together, our results reveal an interaction between BRs, auxin, and ABA in the control of root growth and indicate that altered sensitivity to ABA is partly responsible for the brx short-root phenotype.
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The protein kinase casein kinase 2 (CK2) phosphorylates different components of the RNA polymerase I (Pol I) transcription machinery and exerts a positive effect on rRNA gene (rDNA) transcription. Here we show that CK2 phosphorylates the transcription initiation factor TIF-IA at serines 170 and 172 (Ser170/172), and this phosphorylation triggers the release of TIF-IA from Pol I after transcription initiation. Inhibition of Ser170/172 phosphorylation or covalent tethering of TIF-IA to the RPA43 subunit of Pol I inhibits rDNA transcription, leading to perturbation of nucleolar structure and cell cycle arrest. Fluorescence recovery after photobleaching and chromatin immunoprecipitation experiments demonstrate that dissociation of TIF-IA from Pol I is a prerequisite for proper transcription elongation. In support of phosphorylation of TIF-IA switching from the initiation into the elongation phase, dephosphorylation of Ser170/172 by FCP1 facilitates the reassociation of TIF-IA with Pol I, allowing a new round of rDNA transcription. The results reveal a mechanism by which the functional interplay between CK2 and FCP1 sustains multiple rounds of Pol I transcription.
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Background Fatty acid synthase (FASN) is overexpressed and hyperactivated in several human carcinomas, including lung cancer. We characterize and compare the anti-cancer effects of the FASN inhibitors C75 and (−)-epigallocatechin-3-gallate (EGCG) in a lung cancer model. Methods We evaluated in vitro the effects of C75 and EGCG on fatty acid metabolism (FASN and CPT enzymes), cellular proliferation, apoptosis and cell signaling (EGFR, ERK1/2, AKT and mTOR) in human A549 lung carcinoma cells. In vivo, we evaluated their anti-tumour activity and their effect on body weight in a mice model of human adenocarcinoma xenograft. Results C75 and EGCG had comparable effects in blocking FASN activity (96,9% and 89,3% of inhibition, respectively). In contrast, EGCG had either no significant effect in CPT activity, the rate-limiting enzyme of fatty acid β-oxidation, while C75 stimulated CPT up to 130%. Treating lung cancer cells with EGCG or C75 induced apoptosis and affected EGFR-signaling. While EGCG abolished p-EGFR, p-AKT, p-ERK1/2 and p-mTOR, C75 was less active in decreasing the levels of EGFR and p-AKT. In vivo, EGCG and C75 blocked the growth of lung cancer xenografts but C75 treatment, not EGCG, caused a marked animal weight loss. Conclusions In lung cancer, inhibition of FASN using EGCG can be achieved without parallel stimulation of fatty acid oxidation and this effect is related mainly to EGFR signaling pathway. EGCG reduce the growth of adenocarcinoma human lung cancer xenografts without inducing body weight loss. Taken together, EGCG may be a candidate for future pre-clinical development.
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Tartraatti-resistentin happaman fosfataasin hiljentäminen RNAi menetelmällä: odottamaton vaikutus monosyytti-makrofagi linjan soluissa RNA interferenssi (RNAi) eli RNA:n hiljentyminen löydettiin ensimmäisenä kasveissa, ja 2000-luvulla RNAi menetelmä on otettu käyttöön myös nisäkässoluissa. RNAi on mekanismi, jossa lyhyet kaksi juosteiset RNA molekyylit eli siRNA:t sitoutuvat proteiinikompleksiin ja sitoutuvat komplementaarisesti proteiinia koodaavaan lähetti RNA:han katalysoiden lähetti RNA:n hajoamisen. Tällöin RNA:n koodaamaa proteiinia ei solussa tuoteta. Tässä työssä on RNA interferenssi menetelmän avuksi kehitetty uusi siRNA molekyylien suunnittelualgoritmi siRNA_profile, joka etsii lähetti RNA:sta geenin hiljentämiseen sopivia kohdealueita. Optimaalisesti suunnitellulla siRNA molekyylillä voi olla mahdollista saavuttaa pitkäaikainen geenin hiljeneminen ja spesifinen kohdeproteiinin määrän aleneminen solussa. Erilaiset kemialliset modifikaatiot, mm. 2´-Fluoro-modifikaatio, siRNA molekyylin riboosirenkaassa lisäsivät siRNA molekyylin stabiilisuutta veren plasmassa sekä siRNA molekyylin tehokkuutta. Nämä ovat tärkeitä siRNA molekyylien ominaisuuksia kun RNAi menetelmää sovelletaan lääketieteellisiin tarkoituksiin. Tartraatti-resistentti hapan fosfataasi (TRACP) on entsyymi, joka esiintyy luunsyöjäsoluissa eli osteoklasteissa, antigeenejä esittelevissä dendiriittisissä soluissa sekä eri kudosten makrofageissa, jotka ovat syöjäsoluja. TRACP entsyymin biologista tehtävää ei ole saatu selville, mutta oletetaan että TRACP entsyymin kyvyllä tuottaa reaktiivisia happiradikaaleja on tehtävä sekä luuta hajoittavissa osteoklasteissa sekä antigeenia esittelevissä dendriittisissä soluissa. Makrofageilla, jotka yliekpressoivat TRACP entsyymiä, on myös solunsisäinen reaktiivisten happiradikaalien tuotanto sekä bakteerin tappokyky lisääntynyt. TRACP-geenin hiljentämiseen tarkoitetut spesifiset DNA ja siRNA molekyylit aiheuttivat monosyytti-makrofagilinjan soluviljelymallissa TRACP entsyymin tuoton lisääntymistä odotusten vastaisesti. DNA ja RNA molekyylien vaikutusta TRACP entsyymin tuoton lisääntymiseen tutkittiin myös Tolllike reseptori 9 (TLR9) poistogeenisestä hiirestä eristetyissä monosyyttimakrofaagisoluissa. TRACP entsyymin tuoton lisääntyminen todettiin sekvenssistä ja TLR9:stä riippumattomaksi vasteeksi solun ulkopuolisia DNA ja RNA molekyylejä vastaan. Havainto TRACP entsyymin tuoton lisääntymisestä viittaa siihen, että TRACP entsyymillä on tehtävä solun immuunipuolustusjärjestelmässä.
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Using the yeast two-hybrid system, we identified the mu 2 subunit of the clathrin adaptor complex 2 as a protein interacting with the C-tail of the alpha 1b-adrenergic receptor (AR). Direct association between the alpha 1b-AR and mu 2 was demonstrated using a solid phase overlay assay. The alpha 1b-AR/mu 2 interaction occurred inside the cells, as shown by the finding that the transfected alpha 1b-AR and the endogenous mu 2 could be coimmunoprecipitated from HEK-293 cell extracts. Mutational analysis of the alpha 1b-AR revealed that the binding site for mu 2 does not involve canonical YXX Phi or dileucine motifs but a stretch of eight arginines on the receptor C-tail. The binding domain of mu 2 for the receptor C-tail involves both its N terminus and the subdomain B of its C-terminal portion. The alpha 1b-AR specifically interacted with mu 2, but not with the mu 1, mu 3, or mu 4 subunits belonging to other AP complexes. The deletion of the mu 2 binding site in the C-tail markedly decreased agonist-induced receptor internalization as demonstrated by confocal microscopy as well as by the results of a surface receptor biotinylation assay. The direct association of the adaptor complex 2 with a G protein-coupled receptor has not been reported so far and might represent a common mechanism underlying clathrin-mediated receptor endocytosis.
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The objective of this work was to evaluate the accuracy of digestion techniques using nitric and perchloric acid at the ratios of 2:1, 3:1, and 4:1 v v-1, in one- or two-step digestion, to estimate chromium contents in cattle feces, using sodium molybdate as a catalyst. Fecal standards containing known chromium contents (0, 2, 4, 6, 8, and 10 g kg-1) were produced from feces of five animals. The chromium content in cattle feces is accurately estimated using digestion techniques based on nitric and perchloric acids, at a 3:1 v v-1 ratio, in one-step digestion, with sodium molybdate as a catalyst.
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Laktoosi eli maitosokeri on tärkein ainesosa useimpien nisäkkäiden tuottamassa maidossa. Sitä erotetaan herasta, juustosta ja maidosta. Laktoosia käytetään elintarvike- ja lääketeollisuuden raaka-aineena monissaeri tuotteissa. Lääketeollisuudessa laktoosia käytetään esimerkiksi tablettien täyteaineena. Hapettamalla laktoosia voidaan valmistaa laktobionihappoa, 2-keto-laktobionihappoa ja laktuloosia. Laktobionihappoa käytetään biohajoavien pintojen ja kosmetiikkatuotteiden valmistuksessa, sekä sisäelinten säilöntäliuoksissa, joissa laktobionihappo estää happiradikaalien aiheuttamien kudosvaurioiden syntymistä. Tässä työssä laktoosia hapetettiin laktobionihapoksi sekoittimella varustetussa laboratoriomittakaavaisessa panosreaktorissa käyttäenkatalyyttinä palladiumia aktiivihiilellä. Muutamissa kokeissa katalyytin promoottorina käytettiin vismuttia, joka hidastaa katalyytin deaktivoitumista. Työn tarkoituksena oli saada lisää tietoa laktoosin hapettamisen kinetiikasta. Laktoosin hapettumisessa laktobionihapoksi havaittiin selektiivisyyteen vaikuttavan muunmuassa reaktiolämpötila, paine, pH ja käytetyn katalyytin määrä. Katalyyttiä kierrättämällä eri kokeiden välillä saatiin paremmat konversiot, selektiivisyydet ja saannot. Parhaat koetulokset saatiin hapetettaessa synteettisellä ilmalla 60 oC lämpötilassa ja 1 bar paineessa. Tehdyissä kokeissa pH:n säätö tehtiin manuaalisesti, joten pH ei pysynyt koko ajan haluttuna. Laktoosin konversio oli parhaimmillaan 95 %. Laktobionihapon suhteellinen selektiivisyys oli 100% ja suhteellinen saanto 100 %. Kinetiikan matemaattinen mallinnus tehtiin Modest-ohjelmalla käyttäen kokeista saatuja mittaustuloksia.Ohjelman avulla estimoitiin parametreja ja saatiin matemaattinen malli reaktorille. Tässä työssä tehtiin kineettinen mallinnus myös ravistelureaktorissa tehdyille laktoosin hapetuskokeille, missä pH pysyi koko ajan haluttuna 'in-situ' titrauksen avulla. Työn yhteydessä selvitettiin myös mahdollisuutta käyttää monoliittikatalyyttejä laktoosin hapetusreaktiossa.
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Abstract:The objective of this work was to evaluate the effect of abscisic acid, applied at different rates and different fruit developmental stages, on the thinning of 'Chiripá' peach. Abscisic acid (ABA) at 500 mg L-1 was applied at three stages of fruit development based on lignin deposition: stage 1, at 24 days after full bloom (DAFB); stage 2, at 40 DAFB; and stage 3, at 52 DAFB. Only ABA application at stage 2 - 40 DAFB - reduced fruit set and the number of fruit per plant. Three ABA concentrations (350, 500, and 750 mg L-1) were then applied at 40 DAFB. All rates increased fruit ethylene production and fruit abscission.
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PAH (N-(4-aminobenzoyl)glycin) clearance measurements have been used for 50 years in clinical research for the determination of renal plasma flow. The quantitation of PAH in plasma or urine is generally performed by colorimetric method after diazotation reaction but the measurements must be corrected for the unspecific residual response observed in blank plasma. We have developed a HPLC method to specifically determine PAH and its metabolite NAc-PAH using a gradient elution ion-pair reversed-phase chromatography with UV detection at 273 and 265 nm, respectively. The separations were performed at room temperature on a ChromCart (125 mmx4 mm I.D.) Nucleosil 100-5 microm C18AB cartridge column, using a gradient elution of MeOH-buffer pH 3.9 1:99-->15:85 over 15 min. The pH 3.9 buffered aqueous solution consisted in a mixture of 375 ml sodium citrate-citric acid solution (21.01 g citric acid and 8.0 g NaOH per liter), added up with 2.7 ml H3PO4 85%, 1.0 g of sodium heptanesulfonate and completed ad 1000 ml with ultrapure water. The N-acetyltransferase activity does not seem to notably affect PAH clearances, although NAc-PAH represents 10.2+/-2.7% of PAH excreted unchanged in 12 healthy subjects. The performance of the HPLC and the colorimetric method have been compared using urine and plasma samples collected from healthy volunteers. Good correlations (r=0.94 and 0.97, for plasma and urine, respectively) are found between the results obtained with both techniques. However, the colorimetric method gives higher concentrations of PAH in urine and lower concentrations in plasma than those determined by HPLC. Hence, both renal (ClR) and systemic (Cls) clearances are systematically higher (35.1 and 17.8%, respectively) with the colorimetric method. The fraction of PAH excreted by the kidney ClR/ClS calculated from HPLC data (n=143) is, as expected, always <1 (mean=0.73+/-0.11), whereas the colorimetric method gives a mean extraction ratio of 0.87+/-0.13 implying some unphysiological values (>1). In conclusion, HPLC not only enables the simultaneous quantitation of PAH and NAc-PAH, but may also provide more accurate and precise PAH clearance measurements.
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The protection of arginine (Arg) side chains is a crucial issue in peptide chemistry because of the propensity of the basic guanidinium group to produce side reactions. Currently, sulfonyl-type protecting groups, such as 2,2,5,7,8-pentamethylchroman (Pmc) and 2,2,4,6,7-pentamethyldihydrobenzofurane (Pbf), are the most widely used for this purpose. Nevertheless, Arg side chain protection remains problematic as a result of the acid stability of these two compounds. This issue is even more relevant in Arg-rich sequences, acid-sensitive peptides and large-scale syntheses. The 1,2-dimethylindole-3-sulfonyl (MIS) group is more acid-labile than Pmc and Pbf and can therefore be a better option for Arg side chain protection. In addition, MIS is compatible with tryptophan-containing peptides.
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Orosomucoid (ORM) phenotyping has been performed on 329 unrelated Swiss subjects, using immobilized pH gradients with 8 M urea and 2% v/v 2-mercaptoethanol followed by immunoblotting. After desialylation the band patterns of ORM confirmed that the polymorphism of the structural locus ORM1 is controlled by three codominant autosomal alleles (ORM1*F1, ORM1*S and ORM1*F2). One rare and one new allele were detected. The rare variant, tentatively assigned to the second structural locus ORM2, is observed in a cathodal position and named ORM2 B1. The new variant, tentatively assigned to the first structural locus ORM1, is observed in a region located between ORM1 S and ORM1 F2, and named ORM1 F3. Moreover, the pI values of the ORM variants have been measured accurately with Immobiline Dry Plates (LKB): they were found to be within the pH range 4.93-5.14.
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Preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol was carried out by the enzymatic hydrolysis of halohydrin palmitates using biocatalysts. Halohydrin palmitates were prepared by various methods from palmitic acid and 1,2-octanediol. A tandem hydrolysis was carried out using lipases from Candida antarctica (Novozym® 435), Rhizomucor miehei (Lipozyme IM), and “resting cells” from a Rhizopus oryzae strain that was not mycotoxigenic. The influence of the enzyme and the reaction medium on the selective hydrolysis of isomeric mixtures of halohydrin esters is described. Novozym® 435 allowed preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol after 1–3 h ofreaction at 40 °C in [BMIM][PF6].