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1.
Development ; 149(11)2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35666088

RESUMO

The evolutionarily conserved C-terminal binding protein (CtBP) has been well characterized as a transcriptional co-repressor. Herein, we report a previously unreported function for CtBP, showing that lowering CtBP dosage genetically suppresses Polycomb group (PcG) loss-of-function phenotypes while enhancing that of trithorax group (trxG) in Drosophila, suggesting that the role of CtBP in gene activation is more pronounced in fly development than previously thought. In fly cells, we show that CtBP is required for the derepression of the most direct PcG target genes, which are highly enriched by homeobox transcription factors, including Hox genes. Using ChIP and co-IP assays, we demonstrate that CtBP is directly required for the molecular switch between H3K27me3 and H3K27ac in the derepressed Hox loci. In addition, CtBP physically interacts with many proteins, such as UTX, CBP, Fs(1)h and RNA Pol II, that have activation roles, potentially assisting in their recruitment to promoters and Polycomb response elements that control Hox gene expression. Therefore, we reveal a prominent activation function for CtBP that confers a major role for the epigenetic program of fly segmentation and development.


Assuntos
Proteínas de Drosophila , Genes Homeobox , Oxirredutases do Álcool , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Ligação Proteica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional/genética
2.
Biochem Biophys Res Commun ; 641: 93-101, 2023 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-36525929

RESUMO

Neuroligins (NLGNs) are one of the autism susceptibility genes, however, the mechanism that how dysfunction of NLGNs leads to Autism remains unclear. More and more studies have shown that the transcriptome alteration may be one of the important factors to generate Autism. Therefore, we are very concerned about whether Neuroligins would affect transcriptional regulation, which may at last lead to Autism. As a single-transmembrane receptor, proteolytic cleavage is one of the most important posttranslational modifications of NLGN proteins. In this study, we demonstrated the existence of DNlg3 C-terminal fragment. Studies in the S2 cells and HEK293T cells showed the evidence for nuclear access of the DNlg3 C-terminal fragment. Then we identified the possible targets of DNlg3 C-terminal fragment after its nuclear access by RNA-seq. The bioinformatics analysis indicated the transcriptome alteration between dnlg3 null flies and wild type flies focused on genes for the innate immune responses. These results were consistent with the infection hypotheses for autism. Our study revealed the nuclear access ability of DNlg3 c-terminal fragment and its possible function in transcriptional regulation of the innate immune response genes. This work provides the new links between synaptic adhesion molecule NLGNs and immune activation, which may help us to get a deeper understanding on the relationship between NLGNs and Autism.


Assuntos
Moléculas de Adesão Celular Neuronais , Processamento de Proteína Pós-Traducional , Humanos , Moléculas de Adesão Celular Neuronais/genética , Células HEK293 , Proteólise , Imunidade Inata/genética
3.
Int J Clin Pharmacol Ther ; 60(3): 146-158, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34846299

RESUMO

OBJECTIVE: Previous clinical studies and meta-analyses have shown controversial results on the association between C3435T polymorphism of the ABCB1 gene and anti-epileptic drug (AED) resistance. Based on the fact that sample size and confounding factors could contribute to the inconsistency, we performed an updated meta-analysis by including the most recent studies, and subgroup analysis was conducted to evaluate the effect of confounding factors on the association. MATERIALS AND METHODS: We searched articles in 6 electronic databases including PubMed, Medline, Embase, Web of science, Cochrane Library, CNKI (China National Knowledge Infrastructure) for relevant articles up to June 2020. RESULTS: The current analysis showed that the C allele of C3435T variant was a risk factor for drug resistance in the overall populations (C allele vs. T allele, OR: 1.13; 95% CI: 1.02 - 1.25; p = 0.02) and in the Caucasians (C allele vs. T allele, OR: 1.09; 95% CI: 1.09 - 1.43; p = 0.002), while no association was observed in Asians and Indians. Particularly, our study reported for the first time that the 3435T allele was more common in epilepsy patients with drug resistance in the Tunisian population (C allele vs. T allele, OR: 0.31; 95% CI: 0.15 - 0.65; p = 0.002). In addition, our present analysis suggested an association between C3435T and AED resistance in cryptogenic, symptomatic, but not in idiopathic patients. Subgroup studies based on age and gender showed no association. CONCLUSION: AED resistance in Caucasian and Tunisian populations may benefit from ABCB1 C3435T genotyping. We recommend that more details, such as gender and etiology of epilepsy, should be taken into account to draw a reliable conclusion in future studies.


Assuntos
Anticonvulsivantes , Epilepsia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Anticonvulsivantes/efeitos adversos , Povo Asiático/genética , Resistência a Medicamentos/genética , Epilepsia/tratamento farmacológico , Epilepsia/genética , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único
4.
Biochem Biophys Res Commun ; 576: 1-6, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34474244

RESUMO

Wnt signaling is one of the major signaling pathways that regulate cell differentiation, tissue patterning and stem cell homeostasis and its dysfunction causes many human diseases, such as cancer. It is of tremendous interests to understand how Wnt signaling is regulated in a precise manner both temporally and spatially. Naked cuticle (Nkd) acts as a negative-feedback inhibitor for Wingless (Wg, a fly Wnt) signaling in Drosophila embryonic development. However, the role of Nkd remains controversial in later fly development, particularly on the canonical Wg pathway. In the present study, we show that nkd is essential for wing pattern formation, such that both gain and loss of nkd result in the disruption of Wg target expression in larvae stage and abnormal adult wing morphologies. Furthermore, we demonstrate that a thirty amino acid fragment in Nkd, identified previously in Wharton lab, is critical for the canonical Wg signaling, but is dispensable for Wg/planar cell polarity pathway. Putting aside the pleiotropic nature of nkd function, i.e. its role in the Decapentaplegic signaling, we conclude that Nkd universally inhibits the canonical Wg pathway across a life span of Drosophila development.


Assuntos
Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/genética , Drosophila/crescimento & desenvolvimento , Via de Sinalização Wnt , Proteína Wnt1/antagonistas & inibidores , Animais , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Retroalimentação Fisiológica , Regulação da Expressão Gênica no Desenvolvimento , Transdução de Sinais
5.
J Plant Res ; 129(6): 1097-1107, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27542160

RESUMO

We isolated the TaMYBsm1 genes, encoding R2R3-type MYB proteins in common wheat, aimed to uncover the possible molecular mechanisms related to drought response. The TaMYBsm1 genes, TaMYBsm1-A, TaMYBsm1-B and TaMYBsm1-D, were isolated and analyzed from the common wheat cultivar Shimai 15. Their expression patterns under PEG 6000 and mannitol were monitored by semi-quantitative RT-PCR and ß-glucuronidase (Gus) assay. The function of TaMYBsm1-D under drought stress in transgenic Arabidopsis plants was investigated, and the germination rate, water loss rate, as well as the proline and malondialdehyde (MDA) content were compared with that in wild type (WT) plants. The expression of three downstream genes (DREB2A, P5CS1 and RD29A) in TaMYBsm1-D transgenic plants was analyzed. The R2R3-MYB domains of the MYBsm1 proteins were highly conserved in plants. In addition, the TaMYBsm1 proteins were targeted to the nucleus and contained transcriptional activation domains (TADs). Gus assay and semi-quantitative RT-PCR analysis demonstrated that the TaMYBsm1 genes were up-regulated when the wheat was treated by PEG and mannitol. Compared with WT plants, the germination rates were much higher, but the water loss rates were much lower in TaMYBsm1-D overexpression plants. TaMYBsm1-D transgenic plants showed distinct higher proline contents but a lower MDA content than the WT plants. The three downstream genes were highly expressed in TaMYBsm1-D transgenic plants. We concluded from these results that TaMYBsm1 genes play an important role in plant drought stress tolerance through up-regulation of DREB2A, P5CS1 and RD29A. The increase of proline content and decrease of MDA content may also be involved in the drought response.


Assuntos
Arabidopsis/genética , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Triticum/fisiologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/metabolismo , Triticum/genética
6.
Luminescence ; 31(3): 851-5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26482114

RESUMO

In the present work, a novel 5-methyl-thiophene-carbaldehyde-functionalized rhodamine 6G Schiff base (RA) was designed and easily prepared as an Al(3+) fluorescent and colorimetric probe, which could selectively and sensitively detect Al(3+) by showing enhanced fluorescence emission. Meanwhile distinct color variation from colorless to pink also provided 'naked eye' detection of Al(3+), due to the ring spirolactam opening of the rhodamine derivative. Other metal ions (including K(+), Mg(2+), Na(+), Ba(2+), Mn(2+), Cd(2+), Fe(2+), Ni(2+), Pb(2+), Zn(2+), Hg(2+), Co(2+), Li(+), Sr(2+) and Cu(2+)) could only induce limited interference. The detection limit of the fluorescent probe was estimated to be 4.17 × 10(-6) M, the binding constant of the RA-Al(3+) complex was 1.4 × 10(6) M(-1). Moreover, this fluorescent probe RA possessed high reversibility. As aluminum is a ubiquitous metal in nature and plays vital roles in many biological processes, this chemosensor could be explored for biological study applications.


Assuntos
Alumínio/análise , Corantes Fluorescentes/química , Hidrazonas/química , Rodaminas/química , Tiofenos/química , Fluorescência , Corantes Fluorescentes/síntese química
7.
Plant Cell Rep ; 34(5): 755-66, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25604990

RESUMO

KEY MESSAGE: TaUBA functions as a negative regulator of salt and drought stress response in transgenic Arabidopsis, either the UBA domain or the zinc finger domain is crucial for TaUBA's function. TaUBA (DQ211935), which is a UBA domain-containing protein in wheat, was cloned and functionally characterized. Southern blot suggested that TaUBA is a low copy gene in common wheat. qRT-PCR assay showed that the expression of TaUBA was strongly induced by salt and drought stress. When suffering from drought and salt stresses, lower proline content and much higher MDA content in the TaUBA overexpressors were observed than those of the wild-type control, suggesting TaUBA may function as a negative regulator of salt and drought stress response in plants. To study whether the UBA domain or the zinc finger domain affects the function of TaUBA, TaUBAΔUBA (deletion of UBA domain) and TaUBA-M (Cys464Gly and Cys467Gly) overexpression vectors were constructed and transformed into Arabidopsis. Upon drought and salt stresses, the TaUBAΔUBA-and TaUBA-M-overexpressed plants accumulated much more proline and lower MDA than the wild-type control, the TaUBA-overexpressors lost water more quickly than TaUBAΔUBA-and TaUBA-M-overexpressed plants as well as the wild-type control, suggesting that overexpression of TaUBAΔUBA or TaUBA-M improved the drought and salt tolerance of transgenic Arabidopsis plants and the possibility of ubiquitination role in the regulation of osmolyte synthesis and oxidative stress responses in mediating stress tolerance. qRT-PCR assay of stress-related genes in transgenic plants upon drought and salt stresses suggested that TaUBA may function through down-regulating some stress related-transcription factors and by regulating P5CSs to cope with osmotic stress.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Triticum/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Secas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Estrutura Terciária de Proteína , Tolerância ao Sal , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triticum/fisiologia
8.
Materials (Basel) ; 17(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38793247

RESUMO

Both microvoids and helium (He) impurities are widely present in tungsten (W) plasma-facing materials (PFMs), where the interaction between microvoids and He atoms has led to the intriguing development of microvoids. In this paper, we comprehensively investigated the interaction between He atoms and trivacancy (V3), a fundamental microvoid in W-PFMs, at the level of tight-binding theory. Our study showed that He atoms can catalyze the decomposition of the original V3 or facilitate its transformation into another V3 variant. We propose that a He atom near the V3 defect induces significant changes in the distribution of d-electron charges within the W atoms lining the inner wall of the V3 defect, making the W atom nearest to this He atom cationic and the other W atoms anionic. The attractive interaction between them promotes the decomposition and deformation of V3. As electronic excitation increases, the ionization of W atoms on the V3 wall gradually intensifies, thereby enhancing the cationic characteristics of the W atoms closest to the He atom. This process also prompts other W atoms to shift from anions to cations, leading to a transition in the electrostatic interactions between them from attraction to repulsion. This transformation, driven by electronic excitation, plays a significant inhibitory role in the decomposition and deformation of V3.

9.
Acta Crystallogr C ; 69(Pt 1): 61-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23282916

RESUMO

The contributions of the amino and imino resonance forms to the ground-state structures of 2-amino-4-methylpyridinium nitrate, C(6)H(9)N(2)(+)·NO(3)(-), and the previously reported 2-amino-5-methylpyridinium nitrate [Yan, Fan, Bi, Zuo & Zhang (2012). Acta Cryst. E68, o2084], were studied using a combination of IR spectroscopy, X-ray crystallography and density functional theory (DFT). The results show that the structures of 2-amino-4-methylpyridine and 2-amino-5-methylpyridine obtained upon protonation are best described as existing largely in the imino resonance forms.


Assuntos
Cristalografia por Raios X , Nitratos/química , Compostos de Piridínio/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Teoria Quântica
10.
J Nutr Biochem ; 121: 109430, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37597817

RESUMO

Apigenin, a flavonoid that widely existed in vegetables and fruits, possesses anticarcinogenic, low toxicity, and no mutagenic properties, suggesting that apigenin is a potential therapeutic agent for tumors. However, the underlying anti-cancer molecular target of apigenin is still unclear. Therefore, to reveal the direct target and amino acid site of apigenin against colorectal cancer is the focus of this study. In the present study, the results proved that the anti-CRC activity of apigenin was positively correlated with pyruvate kinase M2 (PKM2) expression, characterized by the inhibition of cell proliferation and increase of apoptotic effects induced by apigenin in LS-174T cells of knock down PKM2. Next, pull-down and MALDI-TOF/TOF analysis determined that apigenin might interact directly with PKM2 in HCT-8 cells. Further, the study confirmed that lysine residue 433 (K433) was a key amino acid site for PKM2 binding to apigenin. Apigenin restricted the glycolysis of LS-174T and HCT-8 cells by targeting the K433 site of PKM2, thereby playing an anti-CRC role in vivo and in vitro. Meanwhile, apigenin markedly attenuated tumor growth without any adverse effects. Taken together, these findings reveal that apigenin is worthy of consideration as a promising PKM2 inhibitor for the prevention of CRC.


Assuntos
Neoplasias Colorretais , Humanos , Aminoácidos/metabolismo , Apigenina/farmacologia , Apigenina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Glicólise , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Proteínas de Ligação a Hormônio da Tireoide
11.
Yi Chuan ; 34(6): 659-65, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22698735

RESUMO

Neandertal is our closest known relative and also an archaic hominid reserving the richest fossils. Whether the Neandertals exchanged their DNA with modern human or not is a matter of debate on the modern human origin. The progresses on the mitochondrial and nuclear genomes of Neandertals in recent years were reviewed in this paper. Recent study has revealed possible genetic contribution of Neandertals to the modern human to some extent, which arose the rethinking of modern human origin. The experiences gained in the research on Neandertals will benefit the study on archaic hominids, unravel the mystery of modern human origin, and enrich the relative theoretical systems in evolutionary biological field.


Assuntos
Evolução Biológica , Genoma , Homem de Neandertal/genética , Animais , Fósseis , Hominidae/genética , Humanos
12.
FEBS J ; 289(20): 6324-6341, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35655387

RESUMO

During Drosophila development, Polycomb-group and Trithorax group proteins function to ensure correct maintenance of transcription patterns by epigenetically repressing or activating target gene expression. To get a deep insight into the PcG and trxG pathways, we investigated a BRCT domain-containing protein called PTIP, which was generally identified as a transcriptional coactivator and belongs to the TRR complex. At the genome scale, we sorted given PTIP-binding peaks into two groups: PTIP/TRR-cobound and PTIP/PC-cobound peaks. In particular, we found that PTIP mediates the molecular switch between H3K4me3/H3K27ac and H3K27me3 histone modifications at TRR or PC occupied regions. Thus, we suggest that PTIP is a mediator rather than a dedicated co-activator along PcG and trxG pathways. Our hypothesis is further supported by the genetic assay: PTIP interacts genetically with either PcG or TrxG in a dosage-dependent manner, suggesting that PTIP functions as a co-factor of PcG/TrxG proteins. In addition, in accordance with the analysis of ChIP-seq, these genetic interactions correlate with modified ectopic HOX protein levels in imaginal discs, which reveals an essential role for PTIP in PcG-mediated Hox gene repression. Hence, we reveal a novel role for PTIP in the epigenetic regulation of gene expression along PcG and trxG pathways.


Assuntos
Proteínas de Drosophila , Histonas , Animais , Drosophila/genética , Proteínas de Drosophila/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Genes Homeobox/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Histonas/metabolismo , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo
13.
ACS Appl Mater Interfaces ; 14(9): 11255-11263, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35195003

RESUMO

Iron-based mixed-polyanionic cathode Na4Fe3(PO4)2(P2O7) (NFPP) has advantages of environmental benignity, easy synthesis, high theoretical capacity, and remarkable stability. From NFPP, a novel Li-replaced material NaLi3Fe3(PO4)2(P2O7) (NLFPP) is synthesized through active Na-site structural engineering by an electrochemical ion exchange approach. The NLFPP cathode can show high reversible capacities of 103.2 and 90.3 mA h g-1 at 0.5 and 5C, respectively. It also displays an impressive discharge capacity of 81.5 mA h g-1 at an ultrahigh rate of 30C. Density functional theory (DFT) calculation demonstrates that the formation energy of NLFPP is the lowest among NLFPP, NFPP, and NaFe3(PO4)2(P2O7), indicating that NLFPP is the easiest to form and the conversion from NFPP to NLFPP is thermodynamically favorable. The Li substitution for Na in the NFPP lattice causes an increase in the unit cell parameter c and decreases in a, b, and V, which are revealed by both DFT calculations and in situ X-ray powder diffraction (XRD) analysis. With hard carbon (HC) as the anode, the NLFPP//HC full cell shows a high reversible capacity of 91.1 mA h g-1 at 2C and retains 82.4% after 200 cycles. The proposed active-site-specific structural tailoring via electrochemical ion exchange will give new insights into the design of high-performance cathodes for lithium-ion batteries.

14.
Am J Bot ; 98(8): e210-2, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21821582

RESUMO

PREMISE OF THE STUDY: The development of compound microsatellite markers was conducted in Dysosma pleiantha to investigate genetic diversity and population genetic structure of this threatened medicinal plant. METHODS AND RESULTS: Using the compound microsatellite marker technique, 14 microsatellite markers that were successfully amplified showed polymorphism when tested on 38 individuals from three populations in eastern China. Overall, the number of alleles per locus ranged from 2 to 14, with an average of 7.71 alleles per locus. CONCLUSIONS: These results indicate that these microsatellite markers are adequate for detecting and characterizing population genetic structure and genetic diversity in Dysosma pleiantha.


Assuntos
Berberidaceae/genética , DNA de Plantas/análise , Triagem de Portadores Genéticos/métodos , Repetições de Microssatélites , Polimorfismo Genético , Alelos , Sequência de Bases , Berberidaceae/metabolismo , China , Primers do DNA/genética , DNA de Plantas/genética , Espécies em Perigo de Extinção , Escherichia coli/genética , Escherichia coli/metabolismo , Frequência do Gene , Biblioteca Gênica , Loci Gênicos , Genótipo , Dados de Sequência Molecular
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 43(6): 908-10, 2011 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-22178845

RESUMO

Osteosarcoma is the most common malignant tumor primarily originated from bone, yet puerpera with osteosarcoma is exceedingly rare. We present here a case of a 27-year-old woman who was operated for femoral osteosarcoma 2 years ago. With emergency admission to Peking University Third Hospital she was diagnosed with recurrent osteosarcoma during the second trimester of pregnancy. As pregnancy might promote tumor development, the general principle demanded timely termination of pregnancy after diagnosis, but the patient insisted on giving up all her comprehensive cancer treatment. As a result, a well made plan for the protection of mother and child was carries out to perform cesarean delivery at the end of 32 weeks of gestation under general anesthesia. The baby was delivered successfully and the mother's condition was kept stable. This case highlighted the benefits of multidisciplinary cooperation and balanced the needs of the developing fetus with those of the mother.


Assuntos
Anestesia Geral/métodos , Cesárea , Neoplasias Femorais/patologia , Osteossarcoma/patologia , Complicações Neoplásicas na Gravidez , Adulto , Feminino , Humanos , Recidiva Local de Neoplasia , Gravidez , Terceiro Trimestre da Gravidez
16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 9): o2493, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22059043

RESUMO

In the title compound, C(15)H(12)N(2)O(2), the dihedral angle between the two benzene rings is 83.55 (11)° In the crystal, the molecules are linked by O-H⋯O and N-H⋯O hydrogen bonds.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(5): 1393-7, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21800608

RESUMO

The natural bentonite was purified and changed to sodium form by NaCl via exchange reaction. Their characteristics, such as swelling volume, swelling value, colloid valence, ethylene blue adsorbed and cation exchange capacity, were measured. The results indicate that the property of Na-bentonite is better than that of natural bentonite. Using cetyltrimethylammonium bromide (CTMAB) and homopolymer of dimethyldiallyammomium chloride (PDMDAAC) as organo-intercalating reagents, two organic modified bentonites were prepared and characterized by Fourier transform infrared (FTIR), X-ray powder diffraction (XRD) and BET surface area. The XRD results showed that the CTMAB-bentonite and PDMDAAC-bentonite had typical X-ray diffraction peaks, and the d001 values increased to 1.89 and 1.45 nm, respectively. Combined with the results of FTIR, the modified reagents had been intercalated to the layer of bentonite. The BET areas, pore volumes and average pore diameters of the two organo-bentonites were decreased as compared to that of Na-bentonite.

18.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1361, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21579445

RESUMO

In the title compound, C(16)H(18)N(2)O, the dihedral angle between the benzene rings is 38.5 (2)°. The crystal packing is stabilized by weak C-H⋯N and C-H⋯O inter-actions and aromatic π-π stacking [centroid-centroid separations = 3.620 (5) and 3.546 (4) Å].

19.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 2): o309, 2010 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-21579740

RESUMO

In the zwitterionic title compound, C(17)H(14)N(2)O, the dihedral angle between the naphthalene and pyridine ring systems is 3.56 (9)° and an intra-molecular N-H⋯O hydrogen bond generates an S(6) ring. In the crystal, mol-ecules are linked by C-H⋯O inter-actions.

20.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): o2149, 2010 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-21588435

RESUMO

In the title compound, C(21)H(23)N(3)O(4), the pyrazole ring forms dihedral angles of 21.58 (8) and 66.64 (7)° with the benzene and phenyl rings, respectively. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds.

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