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1.
J Appl Microbiol ; 122(3): 708-718, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27930840

RESUMEN

AIMS: The aim of this study was to elucidate whether grape-associated fungi exert an influence on gushing by their production of surface-active compounds. METHODS AND RESULTS: In preliminary experiments, 58 grape-associated isolates of species within Penicillium and Aspergillus genera were tested for their ability to modify the surface activity of culture supernatants. As the genus Penicillium had a higher potential to change surface activity, further research focused on that genus. Subsequently, supernatants of 36 Penicillium isolates were assessed for their potential to induce gushing in a model system. Isolates of Penicillium oxalicum had the highest potential. Different external factors were investigated for their influence on the intensity of gushing. By using reversed-phase high performance liquid chromatography and subsequent MALDI-TOF MS, SDS-PAGE and nano-ESI-LC-MS/MS analysis, two proteins in the exoproteome of P. oxalicum were identified, which could be linked to the induction of gushing. CONCLUSIONS: Our results suggest that infection of grapes by P. oxalicum may contribute to gushing in sparkling wine. SIGNIFICANCE AND IMPACT OF THE STUDY: In contrast to gushing of beer, the reason for its development in sparkling wine is widely unexplored. Nonetheless, sparkling wine producers have also been affected by this economically damaging phenomenon. This study has first suggested about the occurrence of primary gushing in sparkling wine.


Asunto(s)
Aspergillus/metabolismo , Proteínas Fúngicas/química , Penicillium/metabolismo , Vitis/microbiología , Vino , Aspergillus/aislamiento & purificación , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Hongos/aislamiento & purificación , Hongos/metabolismo , Penicillium/aislamiento & purificación
2.
Faraday Discuss ; 188: 69-79, 2016 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-27098521

RESUMEN

Within a fluid catalytic cracking (FCC) unit, a mixture of catalyst particles that consist of either zeolite Y (FCC-Y) or ZSM-5 (FCC-ZSM-5) is used in order to boost the propylene yield when processing crude oil fractions. Mixtures of differently aged FCC-Y and FCC-ZSM-5 particles circulating in the FCC unit, the so-called equilibrium catalyst (Ecat), are routinely studied to monitor the overall efficiency of the FCC process. In this study, the age of individual catalyst particles is evaluated based upon photographs after selective staining with substituted styrene molecules. The observed color changes are linked to physical properties, such as the micropore volume and catalytic cracking activity data. Furthermore, it has been possible to determine the relative amount of FCC-Y and FCC-ZSM-5 in an artificial series of physical mixtures as well as in an Ecat sample with unknown composition. As a result, a new practical tool is introduced in the field of zeolite catalysis to evaluate FCC catalyst performances on the basis of photo-spectroscopic measurements with an off-the-shelf digital single lens reflex (DSLR) photo-camera with a macro lens. The results also demonstrate that there is an interesting time and cost trade-off between single catalyst particle studies, as performed with e.g. UV-vis, synchrotron-based IR and fluorescence micro-spectroscopy, and many catalyst particle photo-spectroscopy studies, making use of a relatively simple DSLR photo-camera. The latter approach offers clear prospects for the quality control of e.g. FCC catalyst manufacturing plants.

3.
Chem Soc Rev ; 44(20): 7342-70, 2015 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-26382875

RESUMEN

Fluid catalytic cracking (FCC) is one of the major conversion technologies in the oil refinery industry. FCC currently produces the majority of the world's gasoline, as well as an important fraction of propylene for the polymer industry. In this critical review, we give an overview of the latest trends in this field of research. These trends include ways to make it possible to process either very heavy or very light crude oil fractions as well as to co-process biomass-based oxygenates with regular crude oil fractions, and convert these more complex feedstocks in an increasing amount of propylene and diesel-range fuels. After providing some general background of the FCC process, including a short history as well as details on the process, reactor design, chemical reactions involved and catalyst material, we will discuss several trends in FCC catalysis research by focusing on ways to improve the zeolite structure stability, propylene selectivity and the overall catalyst accessibility by (a) the addition of rare earth elements and phosphorus, (b) constructing hierarchical pores systems and (c) the introduction of new zeolite structures. In addition, we present an overview of the state-of-the-art micro-spectroscopy methods for characterizing FCC catalysts at the single particle level. These new characterization tools are able to explain the influence of the harsh FCC processing conditions (e.g. steam) and the presence of various metal poisons (e.g. V, Fe and Ni) in the crude oil feedstocks on the 3-D structure and accessibility of FCC catalyst materials.

4.
Eur J Neurosci ; 41(7): 965-75, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25615590

RESUMEN

Factor VII activating protease (FSAP) is a circulating protease with a putative role in hemostasis, remodeling and inflammation. A polymorphism giving rise to low proteolytic activity has been associated with an increased risk of stroke and carotid stenosis. To date, no in vivo studies or mechanistic information is available to explain these results. Based on the polymorphism data we hypothesize that a lack of endogenous FSAP will increase the severity of stroke. Stroke was induced by applying thrombin in the middle cerebral artery in wild-type (WT) and FSAP(-/-) mice. Increased stroke volume and worsened neurological deficit were observed in FSAP(-/-) mice. Raised levels of FSAP protein were detected in the infarcted area of WT mice together with enhanced leukocyte infiltration and apoptosis in FSAP(-/-) mice. There was a concomitant increase in the activation of the NFκB pathway and decrease in expression of the PI3K/AKT pathway proteins. At a cellular level, FSAP increased cell survival and decreased apoptosis in primary cortical neurons and astrocytes exposed to tPA/NMDA excitotoxicity or oxygen glucose deprivation (OGD)/reoxygenation, respectively. This was mediated via the PI3K/AKT pathway with involvement of the protease activated receptor-1. To corroborate the human epidemiological data, which link FSAP with stroke, we now show that the lack of FSAP in mice worsens the outcome of stroke. In the absence of FSAP there was a stronger inflammatory response and lower cell survival due to insufficient activation of the PI3K/AKT pathway.


Asunto(s)
Isquemia Encefálica/enzimología , Serina Endopeptidasas/deficiencia , Accidente Cerebrovascular/enzimología , Animales , Apoptosis/fisiología , Astrocitos/enzimología , Astrocitos/patología , Encéfalo/enzimología , Encéfalo/patología , Isquemia Encefálica/patología , Movimiento Celular/fisiología , Supervivencia Celular/fisiología , Células Cultivadas , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media , Leucocitos/patología , Leucocitos/fisiología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/enzimología , Neuronas/patología , Receptor PAR-1/metabolismo , Serina Endopeptidasas/genética , Liberación Accidental en Seveso , Accidente Cerebrovascular/patología , Trombina
5.
Nat Commun ; 15(1): 7170, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169026

RESUMEN

The process of hydrodesulfurization is one of the most important heterogeneous catalytic reactions in industry as it helps with reducing global SOx emissions by selectively removing the sulfur contaminants from commercial fuel. In this work, we successfully combine high-pressure scanning tunneling microscopy and reaction modeling using density functional theory to observe the hydrodesulfurization of methanethiol (CH3SH) on the Co-substituted S edges of a Co-promoted MoS2 model catalyst in situ at near-industrial conditions and investigate the plausible reaction pathways. The active sites on the Co-substituted S edges show a time-varying atomic structure influenced by the hydrodesulfurization reaction rate. The involvement of the edge Co site allows for the C-S bond scission to occur at appreciable rates, and is the critical step in the hydrodesulfurization of CH3SH. The atomic structures of the S-edge active sites from our reaction models match excellently with those observed in situ in the experiments.

6.
Phys Rev Lett ; 109(13): 130403, 2012 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-23030071

RESUMEN

We realize and study an attractively interacting two-dimensional Fermi liquid. Using momentum-resolved photoemission spectroscopy, we measure the self-energy, determine the contact parameter of the short-range interaction potential, and find their dependence on the interaction strength. We successfully compare the measurements to a theoretical analysis, properly taking into account the finite temperature, harmonic trap, and the averaging over several two-dimensional gases with different peak densities.

7.
Catal Sci Technol ; 12(4): 1220-1228, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35310769

RESUMEN

The methanol-to-hydrocarbons (MTH) process, commonly catalyzed by zeolites, is of great commercial interest and therefore widely studied both in industry and academia. However, zeolite-based catalyst materials are notoriously hard to study at the nano-scale. Atom probe tomography (APT) is uniquely positioned among the suite of characterization techniques, as it can provide 3D chemical information with sub-nm resolution. In this work, we have used APT to study the nano-scale coking behavior of zeolite SSZ-13 and its relation to bulk coke formation on the macro-/micro-scale studied with operando and in situ UV-vis spectroscopy and microscopy. Radial distribution function analysis (RDF) of the APT data revealed short carbon-carbon length scale affinities, consistent with the formation of larger aromatic molecules (coke species). Using nearest neighbor distribution (NND) analysis, an increase in the homogeneity of carbon was found with increasing time-on-stream. However, carbon clusters could not be isolated due to spatial noise and limited clustering. Therefore, it was found that the coke formation in zeolite SSZ-13 (CHA) is reasonably homogeneous on the nano-scale, and is rather similar to the silicoaluminophosphate analogue SAPO-34 (CHA) but different in nano-scale coking behavior compared to previously studied zeolite ZSM-5 (MFI).

8.
Mol Hum Reprod ; 16(9): 665-84, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20406800

RESUMEN

Mitotic centromere-associated kinesin (MCAK) is an ATP-dependent microtubule (MT) depolymerase regulated by Aurora kinase (AURK) phosphorylation and implicated in resolution of improper MT attachments in mitosis. Distribution of MCAK was studied in oocyte maturation by anti-MCAK antibody, anti-tubulin antibody, anti-AURKB antibody and anti-centromere antibody (ACA) and by the expression of MCAK-enhanced green fluorescent protein fusion protein in maturing mouse oocytes. Function was assessed by knockdown of MCAK and Mad2, by inhibiting AURK or the proteasome, by live imaging with polarization microscope and by chromosomal analysis. The results show that MCAK is transiently recruited to the nucleus and transits to spindle poles, ACA-positive domains and chiasmata at prometaphase I. At metaphase I and II, it is present at centrosomes and centromeres next to AURKB and checkpoint proteins Mad2 and BubR1. It is retained at centromeres at telophase I and also at the midbody. Knockdown of MCAK causes a delay in chromosome congression but does not prevent bipolar spindle assembly. MCAK knockdown also induces a meiosis I arrest, which is overcome by knockdown of Mad2 resulting in chiasma resolution, chromosome separation, formation of aberrant meiosis II spindles and increased hypoploidy. In conclusion, MCAK appears to possess a unique distribution and function in oocyte maturation. It is required for meiotic progression from meiosis I to meiosis II associated with silencing of the spindle assembly checkpoint. Alterations in abundance and activity of MCAK, as implicated in aged oocytes, may therefore contribute to the loss of control of cell cycle and chromosome behaviour, thus increasing risk for errors in chromosome segregation and aneuploidy.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Centrómero/enzimología , Cinesinas/metabolismo , Meiosis , Mitosis , Oocitos/enzimología , Huso Acromático/enzimología , Animales , Aurora Quinasa B , Aurora Quinasas , Proteínas de Ciclo Celular/genética , Nucléolo Celular/enzimología , Células Cultivadas , Centrómero/efectos de los fármacos , Segregación Cromosómica , Inhibidores de Cisteína Proteinasa/farmacología , Femenino , Cinesinas/genética , Proteínas Mad2 , Ratones , Microinyecciones , Oocitos/efectos de los fármacos , Fosforilación , Ploidias , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Transporte de Proteínas , Interferencia de ARN , Proteínas Recombinantes de Fusión/metabolismo , Huso Acromático/efectos de los fármacos , Factores de Tiempo
9.
Reprod Biomed Online ; 19(3): 352-68, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19778480

RESUMEN

Aurora kinases comprise a family of phosphoproteins performing multiple functions in mitosis and meiosis. Because Aurora kinase B (AURKB) expression is altered in aged oocytes and there is only limited information on its function in meiosis, it was decided to study the spatial distribution and co-localization of AURKB with other regulatory proteins at centromeres during mouse oocyte maturation. AURKB associates with chromosomes after germinal vesicle breakdown, is enriched at centromeres from prometaphase I and transits to the spindle midzone at late anaphase I. Preferential inhibition of AURKB by low concentrations of ZM 447439 inhibitor prevents polar body formation and affects spindle formation and chromosome congression at meiosis I, associated with expression of BubR1 checkpoint protein at kinetochores. Release of cohesion between sister chromatids appears inhibited resulting in failure of chiasma resolution in oocytes progressing to anaphase I. Concomitantly, the inhibitor reduces histone H3 lysine 9 trimethylation at centromeric heterochromatin and affects chromosome condensation. The cytokinesis arrest protects young, healthy oocytes from errors in chromosome segregation although increasing polyploidy. This study shows that changes in activity of AURKB may increase risks for chromosome non-disjunction and aneuploidy in mammalian oocytes, irrespective of age.


Asunto(s)
Centrómero/genética , Segregación Cromosómica/genética , Epigénesis Genética/fisiología , Heterocromatina/genética , Oocitos/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Aneuploidia , Animales , Aurora Quinasa B , Aurora Quinasas , Benzamidas/farmacología , Centrómero/efectos de los fármacos , Centrómero/metabolismo , Segregación Cromosómica/efectos de los fármacos , Femenino , Heterocromatina/efectos de los fármacos , Heterocromatina/metabolismo , Histonas/antagonistas & inhibidores , Histonas/metabolismo , Meiosis/efectos de los fármacos , Meiosis/genética , Ratones , No Disyunción Genética/genética , Oocitos/efectos de los fármacos , Oogénesis/efectos de los fármacos , Oogénesis/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Quinazolinas/farmacología , Huso Acromático/efectos de los fármacos , Huso Acromático/metabolismo
10.
Mutat Res ; 651(1-2): 14-29, 2008 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-18096427

RESUMEN

The spindle assembly checkpoint (SAC) monitors attachment to microtubules and tension on chromosomes in mitosis and meiosis. It represents a surveillance mechanism that halts cells in M-phase in the presence of unattached chromosomes, associated with accumulation of checkpoint components, in particular, Mad2, at the kinetochores. A complex between the anaphase promoting factor/cylosome (APC/C), its accessory protein Cdc20 and proteins of the SAC renders APC/C inactive, usually until all chromosomes are properly assembled at the spindle equator (chromosome congression) and under tension from spindle fibres. Upon release from the SAC the APC/C can target proteins like cyclin B and securin for degradation by the proteasome. Securin degradation causes activation of separase proteolytic enzyme, and in mitosis cleavage of cohesin proteins at the centromeres and arms of sister chromatids. In meiosis I only the cohesin proteins at the sister chromatid arms are cleaved. This requires meiosis specific components and tight regulation by kinase and phosphatase activities. There is no S-phase between meiotic divisions. Second meiosis resembles mitosis. Mammalian oocytes arrest constitutively at metaphase II in presence of aligned chromosomes, which is due to the activity of the cytostatic factor (CSF). The SAC has been identified in spermatogenesis and oogenesis, but gender-differences may contribute to sex-specific differential responses to aneugens. The age-related reduction in expression of components of the SAC in mammalian oocytes may act synergistically with spindle and other cell organelles' dysfunction, and a partial loss of cohesion between sister chromatids to predispose oocytes to errors in chromosome segregation. This might affect dose-response to aneugens. In view of the tendency to have children at advanced maternal ages it appears relevant to pursue studies on consequences of ageing on the susceptibility of human oocytes to the induction of meiotic error by aneugens and establish models to assess risks to human health by environmental exposures.


Asunto(s)
Segregación Cromosómica/genética , Meiosis/genética , Oocitos/metabolismo , Aneuploidia , Animales , Femenino , Humanos , Cinetocoros/metabolismo , Microtúbulos/metabolismo , Oocitos/citología , Huso Acromático/metabolismo
11.
Biochim Biophys Acta ; 1062(2): 271-8, 1991 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-2004114

RESUMEN

The malate carrier of barley (Hordeum vulgare L.) mesophyll vacuoles was highly purified by chromatography on hydroxyapatite followed by affinity-chromatography using 5-amino-1,2,3-benzenetricarboxylic acid as ligand. The carrier, reconstituted in asolectin liposomes, had properties similar to those described previously for the carrier in intact vacuoles (Martinoia, E., Flügge, U.I., Kaiser, G., Heber, U. and Heldt, H.W. (1985) Biochim. Biophys. Acta 806, 311-319). The apparent Km for malate uptake was 2-3 mM, and the uptake was inhibited by other carboxylic acids (preferentially tricarboxylic). The sulfhydryl reagent, p-chloromercuribenzenesulfonate, as well as the anion transport inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid, also inhibited malate uptake. The transport was dependent on the membrane potential with an optimum at about 35 mV.


Asunto(s)
Proteínas Portadoras/aislamiento & purificación , Hordeum/análisis , Malatos/metabolismo , Proteínas de Plantas/aislamiento & purificación , Proteínas Portadoras/metabolismo , Fraccionamiento Celular/métodos , Cromatografía de Afinidad , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Membranas Intracelulares/química , Liposomas/metabolismo , Potenciales de la Membrana/fisiología , Proteínas de Plantas/metabolismo , Vacuolas/química
12.
Biochim Biophys Acta ; 1012(3): 279-83, 1989 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-2547440

RESUMEN

Fish oil has been reported as having beneficial effects on cardiovascular diseases. Elevated serum lipoproteins, prostaglandins and intracellular free calcium concentrations [( Ca2+]i) of the vasculature and thus the phosphoinositide (PI) turnover may be involved in the pathogenesis of these disorders. Therefore, the effect of fish oil on the potency of both low-density lipoprotein (LDL) and angiotensin II (AII) to stimulate the PI turnover in cultured rat vascular smooth muscle cells (VSMC) has been studied. Furthermore, a possible link between PI turnover activity and thromboxane A2 (TXA2) metabolism in these cells has been investigated. In VSMC cultured for up to 7 weeks with either fish oil or n-3 eicosapentaenoic acid (EPA) a decrease to 5-48% of the LDL-induced inositol trisphosphate (IP3) formation (= 100%) was found. A similar range of decreased IP3 synthesis was observed, when AII was used instead of LDL. Both LDL- and AII-stimulated TXA2 synthesis was suppressed concomitantly within the range 34-60%. Blockade of VSMC TXA2 biosynthesis with either indomethacin or TXA2 synthetase blocker (SQ-80338) inhibited LDL-induced formation of IP3 in a dose-dependent manner. Similar results were obtained, when TXA2 receptor coupling antagonists (SQ-27427 or BM-13177) were used. However, blockers of TXA2 synthesis and of TXA2 receptor binding failed to affect AII-induced formation of IP3.


Asunto(s)
Aceites de Pescado/farmacología , Músculo Liso Vascular/metabolismo , Fosfatidilinositoles/metabolismo , Tromboxano A2/metabolismo , Angiotensina II/farmacología , Animales , Células Cultivadas , Ácido Eicosapentaenoico/farmacología , Indometacina/farmacología , Fosfatos de Inositol/biosíntesis , Fosfatos de Inositol/metabolismo , Lipoproteínas LDL/farmacología , Músculo Liso Vascular/efectos de los fármacos , Ratas , Tromboxano A2/biosíntesis
13.
Plant Physiol ; 102(1): 101-105, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-12231801

RESUMEN

Phosphatases in cytosolic fractions, vacuoles, and vacuolar membranes from barley (Hordeum vulgare L.) leaves were found to dephosphorylate inositol 1,4,5-trisphosphate (IP3). 1,4-inositol bisphosphate (1,4-IP2) is the main product of IP3 dephosphorylation by the cytosolic fraction. The activity was strictly Mg2+ dependent. In contrast, IP3 dephosphorylation activity of both the soluble vacuolar and the tonoplast fractions was inhibited up to 50% by Mg2+. When vacuolar membranes were incubated with IP3, 1,4-IP2 was produced only under neutral and slightly alkaline conditions. Under acidic conditions, however, dephosphorylation yielded putative 4,5-inositol bisphosphate. Li+ (20 mM) and Ca2+ (100 [mu]M) strongly inhibited activity in the soluble vacuolar fraction but had only a slight effect on the activities of the cytosolic and tonoplast fractions.

14.
Cell Mol Biol (Noisy-le-grand) ; 51(5): 471-7, 2005 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-16309569

RESUMEN

Heme oxygenase (HO)-1, the inducible isoform of the rate-limiting enzyme of heme degradation, and peroxiredoxin (Prx) I, a thioredoxin-dependent peroxidase, are multifunctional antioxidant stress proteins which are coordinately up-regulated by oxidative stress in cell cultures. HO-1 and Prx I exhibit a different hepatic cellular and subcellular localization. Here, a distinct expression pattern of the two genes was confirmed by in situ hybridization of normal rat liver. Moreover, expression of the HO-1 and Prx I genes was determined in a model of acutely damaged rat liver which was elicited by application of a single dose of carbon tetrachloride (CCl4). The mRNA levels of the HO-1 and Prx I genes were induced in whole livers of CCl4-treated rats with differential kinetics as determined by Northern blot analysis. While HO-1 mRNA was induced up to 48 hr, Prx I exhibited a maximum level of mRNA after 12 hr of treatment with CCl4. CCl4-dependent oxidative stress led to a focal increase of perivenous HO-1 positive liver cells with simultaneous loss of Prx I immunoreactivity. Taken together, the complementary hepatic gene expression pattern of HO-1 and Prx I in response to oxidative stress may suggest a functional interplay of these antioxidant genes.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Hemo-Oxigenasa 1/genética , Hígado/metabolismo , Estrés Oxidativo/genética , Peroxidasas/genética , Animales , Tetracloruro de Carbono , Modelos Animales de Enfermedad , Hemo-Oxigenasa 1/análisis , Cinética , Masculino , Peroxidasas/análisis , Peroxirredoxinas , ARN Mensajero/análisis , Ratas , Ratas Wistar
15.
FEBS Lett ; 411(2-3): 206-10, 1997 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-9271206

RESUMEN

ATP-binding cassette (ABC) transporters are thought to be involved in many cellular detoxification mechanisms. Performing a BLAST search, we found four distinct expressed sequence tags (EST) of Arabidopsis thaliana highly similar to the human and fungal glutathione-conjugate ABC transporters. We studied the expression of the corresponding genes in response to various xenobiotics in an effort to gain information on their function. The abundance of transcripts corresponding to one of the genes (EST1) was not affected by the various compounds tested, whereas the abundance of transcripts corresponding to the other three genes (EST2, EST3, EST4) was increased by 1-chloro-2,4-dinitrobenzene, primisulfuron and IRL 1803. Treatment of Arabidopsis with either primisufuron or IRL 1803 resulted in a more than 40-fold increase in EST2-specific transcripts.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Xenobióticos/farmacología , Secuencia de Aminoácidos , Arabidopsis/efectos de los fármacos , Northern Blotting , Southern Blotting , Clonación Molecular , Marcadores Genéticos , Datos de Secuencia Molecular , Estructura Molecular , Proteínas de Plantas/genética , ARN Mensajero/análisis , ARN Mensajero/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Transcripción Genética
16.
Pediatrics ; 91(5): 922-6, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8474812

RESUMEN

OBJECTIVE: To generate contemporary postnatal growth curves for hospitalized very low birth weight infants. DESIGN: Retrospective survey. SETTING: Tertiary intensive care nursery. PATIENTS: All surviving singleton, appropriate-for-gestational age infants with birth weight < or = 1500 g, born January 1, 1987, to May 31, 1991, who did not develop necrotizing enterocolitis (N = 205). MEASUREMENTS AND RESULTS: Macronutrient intakes and body weights were recorded daily, with crown-heel length and occipital-frontal head circumference recorded weekly up to 105 days of age or hospital discharge, whichever occurred first. Growth curves were generated for four birth weight ranges: 501 through 750, 751 through 1000, 1001 through 1250, and 1251 through 1500 g. Compared to previously published growth curves, the current infants regained birth weight more quickly and exhibited larger average daily weight gains. These differences were most apparent in infants of lowest birth weight. CONCLUSIONS: The "premature growth grid" constructed by Dancis et al more than 40 years ago may no longer be a useful standard of early postnatal growth for present-day very low birth weight, appropriate-for-gestational-age infants. The new weight curves are a more accurate reflection of current in-hospital growth trends, especially for infants weighing < or = 1000 g at birth.


Asunto(s)
Crecimiento , Recién Nacido de Bajo Peso/fisiología , Recien Nacido Prematuro/fisiología , Femenino , Cabeza/crecimiento & desarrollo , Humanos , Recién Nacido , Masculino , Estado Nutricional , Valores de Referencia , Estudios Retrospectivos
17.
J Reprod Immunol ; 22(1): 1-14, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1522561

RESUMEN

Naturally occurring antibodies against the negatively charged phospholipids cardiolipin (CL) and phosphatidylserine (PS) have been associated with recurrent pregnancy loss. One prevalent hypothesis proposes that antiphospholipid antibody (aPL) mediated pathophysiology is through increased placental thrombosis. In this study we investigated the reactivity of three mouse monoclonal aPLs with term and 26 week human placental preparations. Each monoclonal antibody reacted differently with CL and PS; 3SB9b reacted with PS (CL-/PS+), D11A4 reacted with CL (CL+/PS-) and BA3B5C4 reacted with both CL and PS (CL+/PS+). 3SB9b reacted strongly with the syncytiotrophoblastic layer of both formalin fixed and frozen placental tissue. Sporadic reactivity was observed against the cytotrophoblastic layer. BA3B5C4 reacted strongly and specifically with cytotrophoblastic cells. D11A4 had only weak reactivity in the subtrophoblastic stromal region of the placenta in frozen sections. aPL staining was also observed against extravillous cytotrophoblast. BA3B5C4 stained cytoplasmic structures, whereas 3SB9b stained the plasma membrane region with little cytoplasmic staining. These data suggest that the trophoblastic layer is reactive with aPLs and may potentially be directly damaged through mechanisms unrelated to thrombosis. In addition, the trophoblastic layer directly in contact with the maternal circulation is most reactive with aPLs that are PS+ rather than CL+. The differential reactivity of 3SB9b and BA3B5C4 suggests that the antigenic conformation involving PS on the cytotrophoblast is altered concurrent with fusion into the syncytium.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Fosfolípidos/inmunología , Trofoblastos/inmunología , Sitios de Unión de Anticuerpos , Cardiolipinas/inmunología , Vellosidades Coriónicas/inmunología , Femenino , Humanos , Técnicas para Inmunoenzimas , Fosfatidilserinas/inmunología
18.
Int J Dev Neurosci ; 12(3): 185-96, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7942092

RESUMEN

Neuronal ceroid lipofuscinosis (NCL) is a type of lysosomal storage disease resulting in the progressive deterioration of neuronal function. Little is known about the genetics, pathophysiology and biochemical basis of this disease. This is, in part, due to the complexity of the central nervous system and the lack of an in vitro model. In this report, we describe the conditions to establish neuronal cells in primary culture from the brains of newborn English setters with NCL, a canine model for this disease. Over 80% of the neuronal cells from normal dog brain establish well-developed interconnecting networks of long neurites. On the contrary, approximately 50% of the neurons cultured from NCL dog brains do not assemble neurites. Of those NCL neurons with processes, the neurites are routinely shorter and fewer in number than those seen in normal cultures. In addition, the characteristic inclusion bodies, pathological markers for this disease in vivo, are prevalent in the soma of cultured neuronal cells isolated from NCL dog brain. A time-dependent maturation of the inclusion bodies suggests a progression of the disease state in culture. The reduced ability of the NCL neurons to establish neurites prompted us to examine the effects of growth factors on neurite assembly. Our data show that insulin-like growth factor I, epidermal growth factor and platelet-derived growth factor are capable of stimulating neurite outgrowth of NCL neurons. We report the establishment and morphological characterization of neuronal cultures from normal and NCL dog brains. The abnormal morphology of cultured NCL neurons can, in part, be alleviated by supplementing the medium with growth factors. The results suggest that this cellular model of NCL will be useful to study the molecular and physiological mechanisms of NCL disease, as well as to test potential therapeutic agents and candidate genes.


Asunto(s)
Factores de Crecimiento Nervioso/farmacología , Neuritas/efectos de los fármacos , Lipofuscinosis Ceroideas Neuronales/patología , Neuronas/efectos de los fármacos , Animales , Animales Recién Nacidos , Encéfalo/patología , Perros , Técnica del Anticuerpo Fluorescente , Cuerpos de Inclusión/ultraestructura , Masculino , Proteínas del Tejido Nervioso/inmunología , Proteínas del Tejido Nervioso/metabolismo , Neuritas/ultraestructura , Lipofuscinosis Ceroideas Neuronales/genética , Neuronas/ultraestructura , Fenotipo , Factor de Crecimiento Derivado de Plaquetas/inmunología , Factor de Crecimiento Derivado de Plaquetas/metabolismo
19.
Percept Mot Skills ; 81(3 Pt 2): 1379-87, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8684937

RESUMEN

This experiment was designed as a test of the 1993 findings of Rauscher, Shaw, and Ky who reported a positive effect of listening to classical music on spatial reasoning. Present results do not demonstrate the "Mozart effect." In our study, 114 students were pretested on items from the Raven's Progressive Matrices--Advanced Form, then instructed to listen to either 8 min. of Mozart's music, relaxation instructions, or silence. Then subjects were posttested on an equivalent set of Raven's items. The subjects were also asked to provide information about their musical background and preferences. All instructions and treatments were audiotaped and played to individual subjects through earphones in the university language laboratory, ensuring standardization of procedures. Subjects in all 3 treatment groups showed a practice effect, but this improvement in Raven's scores was not dependent on the type of treatment received. There were no differences in Raven's scores among groups before or after treatment so our results do not confirm the prior ones. There was no evidence that the brief music had a different effect on subsequent problem solving according to listeners' musical background and training.


Asunto(s)
Percepción Auditiva , Música , Solución de Problemas , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia por Relajación
20.
Med Device Technol ; 8(4): 28-37, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-10173029

RESUMEN

Some Member States have already established systems to meet the recovery and recycling targets for packaging waste. This article reviews their differences and similarities.


Asunto(s)
Equipos y Suministros , Guías como Asunto , Eliminación de Residuos Sanitarios/legislación & jurisprudencia , Eliminación de Residuos Sanitarios/normas , Embalaje de Productos/legislación & jurisprudencia , Embalaje de Productos/normas , Equipo Reutilizado , Unión Europea , Humanos
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