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1.
J Emerg Med ; 58(3): 375-384, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32001120

RESUMO

BACKGROUND: The outcomes of patients with nonshockable out-of-hospital cardiac arrest (OHCA) are poor, but may be improved by extracorporeal cardiopulmonary resuscitation (E-CPR). OBJECTIVE: To examine the effects of veno-arterial extracorporeal membranous oxygenation (ECMO) as E-CPR in patients with nonshockable OHCA after emergency medical services (EMS) arrival for whom satisfactory cardiopulmonary resuscitation (CPR) was immediately performed. METHODS: Among 16,452 patients enrolled in the SOS-KANTO 2012 study, we examined data on 531 patients aged ≥ 18 years who performed activities of daily living (ADL) well or had moderate disability before the onset of cardiac arrest (CA) and those with normal spontaneous respiration or pulse palpation upon EMS arrival. CPR was performed immediately after CA onset, and advanced life support was provided upon hospital arrival for these patients. We divided patients into ECMO and non-ECMO groups. We retrospectively analyzed background factors and clinical outcomes. RESULTS: E-CPR was performed on 38 (7.2%) patients. In the univariate analysis, the mean age of the ECMO group was lower, ADL function before onset was more favorable, mean body weight was higher, and the mean interval from onset until hospital arrival was shorter than those in the non-ECMO group. One-to 3-month survival or favorable cerebral function outcome rates were higher in the ECMO group than in the non-ECMO group. In the multivariate analysis, ECMO use and the interval from onset until hospital arrival were independent prognostic factors for favorable cerebral functional outcomes at 1 and 3 months. CONCLUSION: E-CPR may be associated with favorable outcomes in carefully selected patients with nonshockable OHCA.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Atividades Cotidianas , Idoso , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos
2.
Mol Genet Genomics ; 291(2): 989-97, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26701352

RESUMO

Overwinter survival has to be under critical regulation in the lifecycle of herbaceous perennial plants. Gentians (Gentiana L.) maintain their perennial life style through producing dormant and freezing-tolerant overwinter buds (OWBs) to overcome cold winter. However, the mechanism acting on such an overwinter survival and the genes/proteins contributing to it have been poorly understood. Previously, we identified an OWB-enriched protein W14/15, a member of a group of α/ß hydrolase fold superfamily that is implicated in regulation of hormonal action in plants. The W14/15 gene has more than ten variant types in Gentiana species. However, roles of the W14/15 gene in OWB survival and functional difference among those variants have been unclear. In the present study, we examined whether the W14/15 gene variants are involved in the mechanism acting on overwinter survival, by crossing experiments using cultivars carrying different W14/15 variant alleles and virus-induced gene silencing experiments. We found that particular types of the W14/15 variants (W15a types) contributed toward obtaining high ability of overwinter survival, while other types (W14b types) did not, or even interfered with the former type gene. This study demonstrates two findings; first, contribution of esterase genes to winter hardiness, and second, paired set or paired partner among the allelic variants determines the ability of overwinter survival.


Assuntos
Adaptação Fisiológica/genética , Esterases/genética , Flores/genética , Gentiana/genética , Alelos , Sequência de Aminoácidos/genética , Flores/crescimento & desenvolvimento , Congelamento , Regulação da Expressão Gênica de Plantas , Gentiana/crescimento & desenvolvimento , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
3.
Chemistry ; 21(47): 16764-8, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26441371

RESUMO

Oligo(2,5-dialkoxy-1,4-phenylenevinylene)s containing three different chiral alkoxy substituents on the phenyl end groups with structurally regular (all trans) controlled repeat units have been prepared; these compounds showed highly enhanced aggregation-induced circular dichroism (AICD; formation of supramolecular polymers), and an inversion of the CD signal was observed even with the same end groups under certain conditions.

4.
Molecules ; 18(2): 1626-37, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23358321

RESUMO

We conducted diastereodifferentiating [2+2] photocycloadditions of cyclo-hexenones modified with a chiral 8-(p-methoxy phenyl)menthyl auxiliary with olefins in water. Although the photoreaction didn't proceed at all in pure water owing to very low solubility, the use of surfactants [sodium dodecyl sulfate (SDS) or dodecylamine hydrochloride (DAH)] and additive (organic solvent) enabled the reactions to progress with moderate to high conversions and yields. Furthermore, we synthesized a new menthol derivative substrate containing a (p-octyloxy)phenyl group for enhancing hydrophobicity, and elucidated that this new substrate was found to be a suitable chiral auxiliary in this asymmetric photoreaction in aqueous system. The additive effect of organic molecules on the yield and diastereoselectivity of the photo-adducts is also discussed.


Assuntos
Alcenos/química , Reação de Cicloadição/métodos , Hidrocarbonetos Cíclicos/síntese química , Luz , Tensoativos/química , Água/química , Ciclopentanos/química , Etilenos/química , Hidrocarbonetos Cíclicos/química , Fotólise , Estereoisomerismo
5.
Zoolog Sci ; 29(3): 185-90, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22379986

RESUMO

Animals possess systems for sensing environmental temperature using temperature-sensitive ion channels called transient receptor potential channels (TRPs). Various TRPs have been identified and characterized in mammals. However, those of ectotherms, such as reptiles, are less well studied. Here, we identify the V subfamily of TRP (TRPV) in two reptile species: Japanese grass lizard (Takydromus tachydromoides) and Japanese four-lined ratsnake (Elaphe quadrivirgata). Phylogenetic analysis of TRPVs indicated that ectothermic reptilian TRPVs are more similar to those of endothermic chicken and mammals, than to other ectotherms, such as frog and fish. Expression analysis of TRPV4 mRNA in the lizard showed that its expression in tissues and organs is specifically controlled in cold environments and hibernation. The mRNA was ubiquitously expressed in seven tissues/organs examined. Both cold-treatment and hibernation lowered TRPV4 expression, but in a tissue/organ-specific manner. Cold-treatment reduced TRPV4 expression in tongue and muscle, while in hibernation it was reduced more widely in brain, tongue, heart, lung, and muscle. Interestingly, however, levels of TRPV4 mRNA in the skin remained unaffected after entering hibernation and cold-treatment, implying that TRPV4 in the skin may act as an environmental temperature sensor throughout the reptilian life cycle, including hibernation. This is the first report, to our knowledge, to describe reptilian TRPV4 in relation to hibernation.


Assuntos
Regulação da Expressão Gênica/fisiologia , Hibernação/fisiologia , Lagartos/fisiologia , Canais de Cátion TRPV/metabolismo , Sequência de Aminoácidos , Animais , Hibernação/genética , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Canais de Cátion TRPV/genética
6.
Mol Genet Genomics ; 285(1): 47-56, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20978911

RESUMO

We have identified multiple alleles for a single gene termed W14/15. This gene encodes closely related but not identical proteins W14 and W15 that accumulate in overwinter buds of Gentiana triflora (Takahashi et al. in Breed Sci 56:39-46, 2006; Hikage et al. in Mol Genet Genomics 278:95-104, 2007). In this study, structural analysis of the W14/15 gene was carried out for 21 different gentian lines/cultivars consisting of 5 different species, to survey species- or line/cultivar-specific haplotypes. Within the samples examined, multiple variant forms were found. Those were categorized into seven major types (type I-VII) and ten subtypes based on the presence of three short insertion/deletion sites, three RFLP sites, and several SNP sites. Each line/cultivar had a distinct set of W14/15 gene variants for an allelic pair. Phylogenetic analysis showed that the W14/15 alleles cluster into groups that are characteristic of gentian species, i.e., G. triflora, G. scabra, G. pneumonanthe, G. septemfida and an unknown species other than the former four. In addition, within the same gentian species, different sets of haplotypes were found. Thus, the W14/15 alleles provide useful landmarks to resolve phylogenies of the genus or section Gentiana, as well as to analyze pedigree and breeding history of the cultivars derived from those Gentiana sp.


Assuntos
Esterases/genética , Genes de Plantas/genética , Gentiana/genética , Sequência de Bases , Éxons/genética , Frequência do Gene/genética , Haplótipos/genética , Dados de Sequência Molecular , Filogenia , Polimorfismo de Nucleotídeo Único/genética
7.
Plant Cell Rep ; 30(6): 1099-106, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21305302

RESUMO

Gynogenesis was investigated on gentian (Gentiana triflora, G. scabra and their hybrids), which is an important ornamental flower. When unfertilized ovules were cultured in 1/2 NLN medium containing a high concentration of sucrose (100 g/l), embryo-like structures (ELS) were induced. Although genotypic variation was observed in ELS induction, all four genotypes produced ELSs ranging from 0.93 to 0.04 ELSs per flower bud. The ovules collected from flower buds of later stages (just before anthesis or flower anthesis) tended to exhibit higher response. The dark culture condition produced more than four times as many ELSs than in 16-h light condition. A significant number of plantlets were directly regenerated from ELSs on MS regeneration medium. The ploidy levels of 179 regenerated plants were determined by flow cytometry, revealing that the majority of them were diploid (55.9%) and haploid (31.3%). When a total of 54 diploid plants were examined by molecular genetic markers, 52 (96.3%) were considered as doubled haploids (DHs). This is the first report showing successful gynogenesis in gentian. The production of haploids and DHs by unfertilized ovule culture opens a novel prospect in gentian F1 hybrid breeding.


Assuntos
Diploide , Gametogênese Vegetal/genética , Gentiana/genética , Haploidia , Técnicas de Cultura de Tecidos/métodos , Fertilização/efeitos da radiação , Citometria de Fluxo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/efeitos da radiação , Gametogênese Vegetal/efeitos da radiação , Marcadores Genéticos , Genótipo , Gentiana/embriologia , Gentiana/fisiologia , Gentiana/efeitos da radiação , Homozigoto , Luz , Regeneração/fisiologia , Regeneração/efeitos da radiação , Sementes/crescimento & desenvolvimento , Sementes/efeitos da radiação
8.
Int J Infect Dis ; 103: 173-175, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33207270

RESUMO

Herpes simplex virus 2 (HSV-2) is a well-known cause of neurological complications. This case study describes the first reported case of reactivated HSV-2 myelitis, which was induced by immunosuppression due to sepsis. During the treatment of meningococcal meningitis, the patient developed quadriparesis and was later diagnosed as HSV-2 myelitis, mimicking ICU-acquired weakness. The case emphasizes the importance of excluding viral myelitis before making the diagnosis of ICU-acquired weakness.


Assuntos
Antibacterianos/uso terapêutico , Herpes Simples/diagnóstico por imagem , Herpesvirus Humano 2/isolamento & purificação , Meningite Meningocócica/complicações , Mielite/diagnóstico por imagem , Quadriplegia/etiologia , Ampicilina/uso terapêutico , Herpes Simples/etiologia , Herpes Simples/virologia , Humanos , Terapia de Imunossupressão/efeitos adversos , Unidades de Terapia Intensiva , Masculino , Meningite Meningocócica/tratamento farmacológico , Pessoa de Meia-Idade , Mielite/etiologia , Mielite/virologia , Ativação Viral
9.
J Exp Bot ; 61(3): 791-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19933315

RESUMO

During rice (Oryza sativa L.) seed development, the primary endosperm nucleus undergoes a series of divisions without cytokinesis, producing a multinucleate cell, known as a syncytium. After several rounds of rapid nuclear proliferation, the syncytium ceases to undergo mitosis; thereafter, the syncytium is partitioned into individual cells by a specific type of cytokinesis called cellularization. The transition between syncytium and cellularization is important in determining the final seed size and is a model for studying the cell cycle and cytokinesis. The involvement of cyclin-dependent kinase (CDK) inhibitors (CKIs) in cell cycle control was investigated here during the transition between syncytium and cellularization. It was found that one of the rice CKIs, Orysa;KRP3, is strongly expressed in the caryopsis at 2 d after flowering (DAF), and its expression is significantly reduced at 3 DAF. The other CKI transcripts did not show such a shift at 2 DAF. In situ hybridization analysis revealed that Orysa;KRP3 is expressed in multinucleate syncytial endosperm at 2 DAF, but not in cellularized endosperm at 3 DAF. Two-hybrid assays showed that Orysa;KRP3 binds Orysa;CDKA;1, Orysa;CDKA;2, Orysa;CycA1;1, and Orysa;CycD2;2. By contrast, Orysa;CDKB2;1 and Orysa;CycB2;2 do not show binding to Orysa;KRP3. Orysa;KRP3 was able to rescue yeast premature cell division due to the dominant positive expression of mutant rice CDKA;1 indicating that Orysa;KRP3 inhibited rice CDK. These data suggest that Orysa;KRP3 is involved in cell cycle control of syncytial endosperm.


Assuntos
Ciclo Celular/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina/genética , Endosperma/citologia , Regulação da Expressão Gênica de Plantas , Células Gigantes/metabolismo , Oryza/genética , Proteínas de Plantas/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo , Quinases Ciclina-Dependentes/antagonistas & inibidores , Ciclinas/metabolismo , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Flores/genética , Perfilação da Expressão Gênica , Genes de Plantas/genética , Células Gigantes/citologia , Especificidade de Órgãos/genética , Oryza/anatomia & histologia , Oryza/citologia , Proteínas de Plantas/metabolismo , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/citologia
10.
Chemistry ; 16(25): 7448-55, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20461835

RESUMO

Upon diastereodifferentiating the [2+2] photocycloaddition of ethylene to a series of p-substituted (-)-8-phenylmenthyl cyclohexenonecarboxylates, the diastereoselectivity was critically controlled by the nature of the substituent introduced to the chiral auxiliary, and the p-nitro-substituted substrate afforded the cycloadducts in 90% diastereomeric excess (de) and with 97% isolated yield. Detailed experimental and theoretical conformation analyses revealed that the stacking interaction of the aromatic auxiliary with the cyclohexenone moiety plays the decisive role in determining the substrate conformation and is, therefore, responsible for the dramatic enhancement of the de. Of particular interest, the product de was directly related to the ellipticity of the substrate, enabling us to "predict" the de prior to photoirradiation.

11.
Biosci Biotechnol Biochem ; 74(7): 1435-40, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20622450

RESUMO

To endure considerable fluctuations in temperature, plants need precise regulation of temperature-controlled gene expression. In this study, the involvement of TAS1 trans-acting siRNA (tasiRNA) in temperature-controlled gene expression was examined in Arabidopsis. The accumulation of TAS1 tasiRNA was downregulated at 4 degrees C. Concomitant with the reduction of TAS1 tasiRNA-mediated cleavage, expression of At1g51670, a target of TAS1 tasiRNA, was upregulated at 4 degrees C in the wild type but not in a dicer-like enzyme (DCL) 4 mutant (dcl4-2), which is impaired in tasiRNA biogenesis. The expression of At4g29760 and of At5g18040, further TAS1 tasiRNA targets, was upregulated both in the wild type and in dcl4-2 at 4 degrees C. However, after shifting the temperature to 22 degrees C, low-temperature-induced expression of At4g29760 rapidly dropped in the wild type, but not in dcl4-2. Thus TAS1 tasiRNA acted as a sweeper for the clearance of excess amounts of At4g29760 transcripts. Our data suggest that differential regulation of TAS1 tasiRNA targets is involved in temperature-controlled gene expression.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , RNA Interferente Pequeno/genética , Temperatura , Proteínas de Arabidopsis/metabolismo , Sequência de Bases , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
Acute Med Surg ; 7(1): e472, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31988784

RESUMO

AIM: In severe urinary tract infection (UTI), susceptible antibiotics should be given. With the recent increase of multidrug-resistant bacteria, especially extended spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E), broad-spectrum antibiotics, such as carbapenems, are used more frequently, which could lead to a further increase of multidrug-resistant bacteria. We aimed to analyze the relationship between initial empirical antibiotic appropriateness and clinical outcomes in UTI, especially in patients with systemic inflammatory response syndrome (SIRS) and ESBL-E. METHODS: A retrospective observational study from 2012 to 2017. RESULTS: Among urine culture-positive cases with ≥105 colony-forming units/mL (n = 1,880), true UTI cases were extracted (n = 844) and divided into the SIRS group (n = 336 [ESBL-E12.8% (43/336)]) and non-SIRS group (n = 508 [ESBL-E12.6% (64/508)]). In the SIRS ESBL-E group, the initial antibiotics were susceptible in 55.8% (24/43), among which 91.7% (22/24) improved and 8.3% (2/24) deteriorated or died. The initial antibiotics were resistant in 44.2% (19/43), among which 47.4% (9/19) improved with the initial antibiotics, 47.4% (9/19) improved after escalating antibiotics, and 5.3% (1/19) deteriorated or died. In the SIRS group, 14 cases had true bacteremia with ESBL-E. Seven cases were initiated with inappropriate antibiotics; four cases showed improvement before or without antibiotic change and three cases improved after antibiotic escalation. CONCLUSION: Initiation of narrow-spectrum antibiotics in septic UTI with ESBL-E might not deteriorate the clinical outcome if promptly escalated on clinical deterioration or with ESBL-E culture results. Further investigation is warranted to guide judicious use of initial antibiotics.

13.
Mol Cell Biol ; 26(23): 8770-80, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16982680

RESUMO

A region encompassing the rat aldolase B gene (aldB) promoter acts as a chromosomal origin of DNA replication (origin) in rat aldolase B-nonexpressing hepatoma cells. To examine replicator function of the aldB origin, we constructed recombinant mouse cell lines in which the rat aldB origin and the mutant derivatives were inserted into the same position at the mouse chromosome 8 by cre-mediated recombination. Nascent strand abundance assays revealed that the rat origin acts as a replicator at the ectopic mouse locus. Mutation of site C in the rat origin, which binds an Orc1-binding protein AlF-C in vitro, resulted in a significant reduction of the replicator activity in the mouse cells. Chromatin immunoprecipitation (ChIP) assays indicated that the reduction of replicator activity was paralleled with the reduced binding of AlF-C and Orc1, suggesting that sequence-specific binding of AlF-C to the ectopic rat origin leads to enhanced replicator activity in cooperation with Orc1. Involvement of AlF-C in replication in vivo was further examined for the aldB origin at its original rat locus and for a different rat origin identified in the present study, which contained an AlF-C-binding site. ChIP assays revealed that both replication origins bind AlF-C and Orc1. We think that the results presented here may represent one mode of origin recognition in mammalian cells.


Assuntos
Frutose-Bifosfato Aldolase/genética , Complexo de Reconhecimento de Origem/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Ligação Competitiva , Imunoprecipitação da Cromatina , Cromossomos/metabolismo , Clonagem Molecular , Ensaio de Desvio de Mobilidade Eletroforética , Frutose-Bifosfato Aldolase/metabolismo , Glutationa Transferase/metabolismo , Integrases , Células L , Camundongos , Dados de Sequência Molecular , Mutagênese Insercional , Ligação Proteica , Ratos , Proteínas Recombinantes/metabolismo , Recombinação Genética , Fatores de Transcrição/química
14.
Chem Commun (Camb) ; (18): 2103-5, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-18438482

RESUMO

3-Arylthiochromone derivatives were synthesized as new photolabile protecting groups, in which the photoreactivity was switchable based on oxidation of the sulfur atom (sulfide and sulfone); the protected substrates , released the corresponding alcohols, amines or carbonxylic acids almost quantitatively under UV-light in neutral condition and the photoproduct showed high fluorescence intensity.


Assuntos
Cromonas/química , Cromonas/síntese química , Óxidos/química , Óxidos/síntese química , Compostos de Sulfidrila/química , Compostos de Sulfidrila/síntese química , Álcoois/síntese química , Álcoois/química , Álcoois/efeitos da radiação , Aminas/síntese química , Aminas/química , Aminas/efeitos da radiação , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/efeitos da radiação , Cromonas/efeitos da radiação , Ciclização , Estrutura Molecular , Óxidos/efeitos da radiação , Fotoquímica , Estereoisomerismo , Compostos de Sulfidrila/efeitos da radiação , Raios Ultravioleta
15.
ACS Omega ; 3(6): 6166-6181, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458800

RESUMO

Reactions of Nb(NAr)(N=C t Bu2)3 (3a, Ar = 2,6-Me2C6H3) with 1.0, 2.0, or 3.0 equiv of Ar'OH (Ar' = 2,6- i Pr2C6H3) afforded Nb(NAr)(N=C t Bu2)2(OAr'), Nb(NAr)(N=C t Bu2)(OAr')2, or Nb(NAr)(OAr')3, respectively (at 25 °C), whereas the reaction with 2.0 equiv of 2,6- t Bu2C6H3OH afforded Nb(NAr)(N=C t Bu2)2(O-2,6- t Bu2C6H3) upon heating (70 °C) without the formation of bis(phenoxide) and the reaction of 3a with 2.0 equiv of 2,4,6-Me3C6H2OH afforded Nb(NAr)(N=C t Bu2)(O-2,4,6-Me3C6H2)2(HN=C t Bu2). Similar reactions of 3a with 1.0 equiv of (CF3)3COH or 2.0 equiv of (CF3)2CHOH afforded Nb(NAr)(N=C t Bu2)2[OC(CF3)3](HN=C t Bu2) or Nb(NAr)(N=C t Bu2)[OCH(CF3)2]2(HN=C t Bu2), respectively. On the basis of their structural analyses and the reaction chemistry, it was suggested that these reactions proceeded via coordination of phenol (alcohol) to Nb and the subsequent proton (hydrogen) transfer to the ketimide (N=C t Bu2) ligand. The reaction of Nb(NAr)(N=C t Bu2)2(OAr') with 1.0 equiv of 2,4,6-Me3C6H2OH gave the disproportionation products Nb(NAr)(N=C t Bu2)(OAr')2 and Nb(NAr)(N=C t Bu2)(O-2,4,6-Me3C6H2)2(HN=C t Bu2) with 1:1 ratio, clearly indicating the presence of the above mechanism and the fast equilibrium (between the ketimide and the phenoxide). The reaction of 3a with 1.0 or 2.0 equiv of C6F5OH afforded Nb(N=C t Bu2)2(OC6F5)3(HN=C t Bu2) as the sole isolated product, which was formed from once generated Nb(NAr)(N=C t Bu2)2(OC6F5)(HN=C t Bu2) by treating with C6F5OH.

16.
ACS Omega ; 3(9): 11041-11049, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459214

RESUMO

Cross-metathesis of unsaturated fatty acid methyl esters (methyl oleate (MO), methyl petroselinate (MP), and methyl erucate (ME), obtained from vegetable oils) with eugenol (obtained from clove oil) proceeded under green, mild conditions (in 2-propanol or ethanol at 50 °C) in the presence of a ruthenium-carbene catalyst (called a second-generation Grubbs catalyst). These metathesis reactions proceeded with both high conversion (>90% of MO, MP) and selectivity (>98%) even with low catalyst loading (0.1 mol % Ru).

17.
ACS Omega ; 2(7): 3886-3900, 2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457695

RESUMO

A series of neutral and cationic palladium(II) complexes containing C 2-symmetric bis(oxazoline) (BOX) ligands, (BOX)PdCl2 (2a-d), (BOX)Pd(Me)Cl (3a-d), and [(BOX)PdMe(2,6-Me2C5H3N)]+PF6 - (4a-d) [BOX: 2,2'-(2-propylidene)bis{(4R)-4-phenyl-5,5-dimethyl-2-oxazoline}, 2,2'-methylenebis{(4R)-4-phenyl-5,5-dimethyl-2-oxazoline}, 2,2'-methylenebis{(4R)-4,5,5-triphenyl-2-oxazoline}, and 2,2'-methylenebis{(4R,5S)-4,5-diphenyl-2-oxazoline}], were prepared, and their structures were determined by X-ray crystallography. It was found that substituents at the 5-position (Ph, Me) in addition to substituents on the bridgehead carbon directly affect the structure around palladium, especially the BOX bite angle and the dihedral angles between the phenyl rings at the 4-position and the N2Pd plane. Treatment of the bridged methylene proton in the BOX ligand (1b-d) with KH afforded the anionic BOX ligand; also, the neutral Pd complexes, (BOX)PdMe(2,6-Me2C5H3N) (5b-d), could thus be prepared by reaction with Pd(Me)Cl(cod) (cod = 1,5-cyclooctadiene); 5b-d showed strong coordination to Pd, as demonstrated by X-ray crystallographic analysis.

18.
ACS Omega ; 2(12): 8660-8673, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457397

RESUMO

(Imido)vanadium(V) dichloride complexes containing 2-(2'-benzimidazolyl)-6-methylpyridine ligand (L) of type V(NR)Cl2(L) [R = 1-adamantyl (Ad, 1), C6H5 (2), and 2,6-Me2C6H3 (3)] have been prepared, and their structures were determined by X-ray crystallography as distorted trigonal bipyramidal structures around vanadium. Reactions with ethylene using 1-3 in the presence of methylaluminoxane (MAO) afforded a mixture of oligomer and polymers, and the compositions were affected by the imido ligand employed. By contrast, 1-3 exhibited remarkable catalytic activities for ethylene polymerization in the presence of Me2AlCl; the phenylimido complex (2) exhibited the highest activity [80 100 kg-PE/mol-V·h turn over frequency (TOF, 2 850 000 h-1, 792 s-1)]. The ethylene copolymerizations with norbornene afforded ultrahigh-molecular-weight copolymers with uniform molecular weight distributions and compositions [e.g., M n = 1.71-2.66 × 106, M w/M n = 2.27-2.53]. On the basis of V nuclear magnetic resonance (51V NMR), electron spin resonance, and V K-edge X-ray absorption near-edge structure (XANES) spectra of the catalyst solution, the observed difference in the catalyst performance in the presence of (between) MAO and Me2AlCl cocatalyst should be due to the formation of different catalytically active species with different oxidation states. Apparent changes in the oxidation state were observed in the (especially in the NMR and XANES) spectra upon addition of Me2AlCl, whereas no significant changes in the spectra were observed in presence of MAO.

19.
Genes Genet Syst ; 81(2): 135-41, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16755137

RESUMO

beta-conglycinin, a major component of seed-storage proteins in soybean, comprises three subunits: alpha, alpha', and beta. Expression of these genes is spatially regulated in a stringent manner and occurs during seed development. To understand the mechanisms that control expression of the alpha subunit gene, we analyzed the nucleotide sequence of the 2.9-kb region upstream of the gene. The upstream sequence up to -1357 or a series of its 5'-deleted derivatives was fused to the beta-glucuronidase (GUS) gene. These reporter gene constructs were introduced into Arabidopsis thaliana plants via Agrobacterium-mediated gene transfer. Prominent GUS activity was detected in developing seeds of the T3 generation when 245 bp or longer sequences of the upstream region were fused to the GUS gene. We found a clear association of decreased GUS activity with a stepwise deletion of a region containing the RY sequence from the original construct. These results are consistent with the notion that multiple sequence elements including the RY sequences are involved in the seed-specific transcriptional activation of the beta-conglycinin alpha subunit gene in soybean.


Assuntos
Arabidopsis/metabolismo , Globulinas/genética , Regiões Promotoras Genéticas/fisiologia , Elementos Reguladores de Transcrição/fisiologia , Sementes/metabolismo , Proteínas de Soja/genética , Antígenos de Plantas , Arabidopsis/crescimento & desenvolvimento , Sequência de Bases , Regulação da Expressão Gênica , Genes Reporter , Vetores Genéticos/metabolismo , Glucuronidase/metabolismo , Dados de Sequência Molecular , Plantas Geneticamente Modificadas/metabolismo , Subunidades Proteicas/genética , Rhizobium/metabolismo , Proteínas de Armazenamento de Sementes , Sementes/crescimento & desenvolvimento , Transdução Genética
20.
Nucleic Acids Res ; 30(23): 5205-12, 2002 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-12466545

RESUMO

The promoter of the rat aldolase B (AldB) gene functions in vivo as an origin of DNA replication in the cells in which transcription of the gene is repressed. Previously, we identified two closely related DNA-binding proteins, AlF-C1 and AlF-C2, which repressed the AldB gene promoter. We also reported that the binding site of these proteins, site C, is one of the required DNA elements of the AldB gene origin/promoter for autonomously replicating activity in transfected cells. In the present study, we show that AlF-C1 and AlF-C2 bind directly to Orc1, a subunit of the origin recognition complex (ORC). Deletion analyses revealed a functional domain in AlF-C2 for binding to Orc1, which is located separately from the DNA-binding domain. In addition, we found a novel protein-interacting domain in Orc1 required for the binding of AlF-C2, which was conserved in human, mouse and Chinese hamster, but not in Drosophila, frog and yeast. Thus, it is assumed that in mammalian cells, sequence- specific DNA-binding proteins are involved in recruiting ORC to regulate replication initiation and/or transcription repression.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Frutose-Bifosfato Aldolase/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B , Regiões Promotoras Genéticas , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Proteínas de Ciclo Celular , Cricetinae , Humanos , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Complexo de Reconhecimento de Origem , Estrutura Terciária de Proteína , Ratos , Ribonucleoproteínas , Alinhamento de Sequência , Fatores de Transcrição , Transcrição Gênica
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