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1.
BMC Plant Biol ; 23(1): 465, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798654

RESUMO

BACKGROUND: The P-stalk is a conserved and vital structural element of ribosome. The eukaryotic P-stalk exists as a P0-(P1-P2)2 pentameric complex, in which P0 function as a base structure for incorporating the stalk onto 60S pre-ribosome. Prior studies have suggested that P0 genes are indispensable for survival in yeast and animals. However, the functions of P0 genes in plants remain elusive. RESULTS: In the present study, we show that rice has three P0 genes predicted to encode highly conserved proteins OsP0A, OsP0B and OsP0C. All of these P0 proteins were localized both in cytoplasm and nucleus, and all interacted with OsP1. Intriguingly, the transcripts of OsP0A presented more than 90% of the total P0 transcripts. Moreover, knockout of OsP0A led to embryo lethality, while single or double knockout of OsP0B and OsP0C did not show any visible defects in rice. The genomic DNA of OsP0A could well complement the lethal phenotypes of osp0a mutant. Finally, sequence and syntenic analyses revealed that OsP0C evolved from OsP0A, and that duplication of genomic fragment harboring OsP0C further gave birth to OsP0B, and both of these duplication events might happen prior to the differentiation of indica and japonica subspecies in rice ancestor. CONCLUSION: These data suggested that OsP0A functions as the predominant P0 gene, playing an essential role in embryo development in rice. Our findings highlighted the importance of P0 genes in plant development.


Assuntos
Oryza , Proteínas Ribossômicas , Animais , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Oryza/genética , Oryza/metabolismo , Ribossomos/metabolismo , Saccharomyces cerevisiae/metabolismo , Desenvolvimento Embrionário
2.
IEEE Trans Vis Comput Graph ; 29(6): 2940-2949, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35061587

RESUMO

Rendering glinty details from specular microstructure enhances the level of realism in computer graphics. However, naive sampling fails to render such effects, due to insufficient sampling of the contributing normals on the surface patch visible through a pixel. Other approaches resort to searching for the relevant normals in more explicit ways, but they rely on special acceleration structures, leading to increased storage costs and complexity. In this article, we propose to render specular glints through a different method: differentiable regularization. Our method includes two steps: first, we use differentiable path tracing to render a scene with a larger light size and/or rougher surfaces and record the gradients with respect to light size and roughness. Next, we use the result for the larger light size and rougher surfaces, together with their gradients, to predict the target value for the required light size and roughness by extrapolation. In the end, we get significantly reduced noise compared to rendering the scene directly. Our results are close to the reference, which uses many more samples per pixel, although our method cannot guarantee unbiased convergence to the reference. The overhead for differentiable rendering and prediction is small, so our improvement is almost free. We demonstrate our differentiable regularization on several normal maps, all of which benefit from the method.

3.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 1): o28, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23476415

RESUMO

In the title compound, C14H12ClN3O2, the acyl-hydrazone base [C(=O)-N-N=C] is essentially planar, with an r.m.s. deviation of 0.0095 Å, and makes a dihedral angle of 12.52 (10)°with the pyridine ring. In the crystal, molecules are linked via pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R2(2)(8) graph-set motif. The dimers are linked via C-H⋯π interactions forming chains along [101].

4.
Eur J Med Chem ; 62: 199-205, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23353753

RESUMO

This communication describes the synthesis and inhibitory activities of thirty-seven novel C-terminal agmatine dipeptides used as screening compounds to study the structure-activity relationship between active-site peptidomimetics and the West Nile virus (WNV) NS2B/NS3 serine protease. Our efforts lead to the discovery of a novel agmatine dipeptide inhibitor (compound 33, IC50 2.6 ± 0.3 µM) with improved inhibitory activity in comparison to the most potent inhibitor described in our recent report [IC50 4.7 ± 1.2 µM; Lim et al., Eur. J. Med. Chem. 46 (2011) 3130-3134]. In addition, our study cleared the contention surrounding the previous X-ray co-crystallization study and an enzyme inhibition report on the binding conformation adopted by active-site peptide aldehydes. Our data should provide valuable insights into the design of future peptidomimetic antivirals against WNV infections.


Assuntos
Agmatina/farmacologia , Dipeptídeos/farmacologia , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/efeitos dos fármacos , Vírus do Nilo Ocidental/enzimologia , Agmatina/síntese química , Agmatina/química , Cristalografia por Raios X , Dipeptídeos/síntese química , Dipeptídeos/química , Relação Dose-Resposta a Droga , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , RNA Helicases/efeitos dos fármacos , Serina Endopeptidases/efeitos dos fármacos , Software , Relação Estrutura-Atividade , Vírus do Nilo Ocidental/efeitos dos fármacos
5.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o2236, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22798892

RESUMO

The mol-ecule of the title compound, C(10)H(12)N(2)O(4), is located around an inversion center. The carboxyl-ate groups are twisted slightly with respect to the pyrazine ring, making a dihedral angle of 2.76 (19)°. In the crystal, mol-ecules are stacked along the c axis via weak C-H⋯O hydrogen bonds.

6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m783, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719334

RESUMO

In the title compound, [Cu(C(13)H(8)N(4)O(3))(H(2)O)]·3H(2)O, the complex molecule, except for the aqua ligand, is essentially planar [r.m.s. deviation = 0.034 (2) Å]. The coordination polyhedron of the Cu(2+) cation is a square-pyramid, with the aqua ligand at the apex. The compound exhibits a three-dimensional structure, which is is stabilized by O-H⋯O and O--H⋯N hydrogen bonds and π-π inter-actions [centroid-centroid distance = 2.987 (3) Å].

7.
Pest Manag Sci ; 68(9): 1306-10, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22573612

RESUMO

BACKGROUND: Bacillus cereus C1L is a plant growth-promoting rhizobacterium and can elicit induced systemic resistance (ISR) in plants against necrotrophic pathogens. However, little is known about ISR elicitors produced by B. cereus C1L, and no ISR elicitor has been identified and characterised. Therefore, the objective of this study is to identify volatile ISR elicitor(s) produced by B. cereus C1L. RESULTS: The volatile metabolites produced by B. cereus C1L were extracted, separated and identified by solid-phase microextraction, gas chromatography and mass spectrometry. Dimethyl disulfide (DMDS) was the only separated metabolite being determined. Afterwards, application of DMDS by means of soil drench significantly protected tobacco and corn plants against Botrytis cinerea and Cochliobolus heterostrophus, respectively, under greenhouse conditions. The results reveal that DMDS could play an important role in ISR by B. cereus C1L. CONCLUSION: This is the first report of DMDS as an elicitor produced by an ISR-eliciting B. cereus strain and its ability to suppress plant fungal diseases under greenhouse conditions. It is suggested that DMDS has potential for practical use in controlling plant foliar diseases besides soil fumigation.


Assuntos
Bacillus cereus/imunologia , Resistência à Doença , Dissulfetos/imunologia , Doenças das Plantas/imunologia , Bacillus cereus/química , Bacillus cereus/fisiologia , Botrytis/efeitos dos fármacos , Botrytis/crescimento & desenvolvimento , Dissulfetos/análise , Dissulfetos/farmacologia , Imunidade Inata , Doenças das Plantas/microbiologia , Nicotiana/imunologia , Nicotiana/microbiologia , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/imunologia , Compostos Orgânicos Voláteis/farmacologia , Zea mays/imunologia , Zea mays/microbiologia
8.
Toxicol Appl Pharmacol ; 261(1): 31-41, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22465936

RESUMO

In continuation to our studies toward the identification of direct anti-cancer targets, here we showed that destruxin B (DB) from Metarhizium anisopliae suppressed the proliferation and induced cell cycle arrest in human colorectal cancer (CRC) HT29, SW480 and HCT116 cells. Additionally, DB induced apoptosis in HT29 cells by decreased expression level of anti-apoptotic proteins Bcl-2 and Bcl-xL while increased pro-apoptotic Bax. On the other hand, DB attenuated Wnt-signaling by downregulation of ß-catenin, Tcf4 and ß-catenin/Tcf4 transcriptional activity, concomitantly with decreased expression of ß-catenin target genes cyclin D1, c-myc and survivin. Furthermore, DB affected the migratory and invasive ability of HT29 cells through suppressed MMPs-2 and -9 enzymatic activities. We also found that DB targeted the MAPK and/or PI3K/Akt pathway by reduced expression of Akt, IKK-α, JNK, NF-κB, c-Jun and c-Fos while increased that of IκBα. Finally, we demonstrated that DB inhibited tumorigenesis in HT29 xenograft mice using non-invasive bioluminescence technique. Consistently, tumor samples from DB-treated mice demonstrated suppressed expression of ß-catenin, cyclin D1, survivin, and endothelial marker CD31 while increased caspase-3 expression. Collectively, our data supports DB as an inhibitor of Wnt/ß-catenin/Tcf signaling pathway that may be beneficial in the CRC management.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Depsipeptídeos/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Depsipeptídeos/isolamento & purificação , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Medições Luminescentes , Metarhizium/química , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fator de Transcrição 4 , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética
9.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): m910, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21836896

RESUMO

In the crystal structure of the centrosymmetric binuclear title complex, [Ni(2)(C(12)H(8)N(2)O(2)S)(2)(CH(3)OH)(4)], there are inter-molecular O-H⋯O, O-H⋯N and O-H⋯S hydrogen bonds. These help to stabilize the structure and link the mol-ecules, forming a three-dimensional network structure. The Ni(2+) cation exists in a slightly distorted octahedral NiNO(5) coordination environment. The thio-phene rings are disordered over two equivalent conformations with occupancies of 0.881 (3) and 0.119 (3).

10.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): m225, 2011 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-21522884

RESUMO

The title complex, [CuBr(C(6)H(4)NO(3))(H(2)O)](n), exhibits a layered structure which is stabilized by inter-molecular O-H⋯O and O-H⋯Br(-) hydrogen bonds, van der Waals forces and π-π inter-actions [centroid-centroid distance = 3.747(4) Å] between the parallel pyridine rings from two neighboring layers.

11.
Artigo em Inglês | MEDLINE | ID: mdl-20008903

RESUMO

Citrus grandis (L.) Osbeck (red wendun) leaves have been used in traditional Chinese medicine to treat several illnesses including diabetes. However, there is no scientific evidence supporting these actions and its active compounds. Two flavone glycosides, rhoifolin and cosmosiin were isolated for the first time from red wendun leaves and, identified these leaves are rich source for rhoifolin (1.1%, w/w). In differentiated 3T3-L1 adipocytes, rhoifolin and cosmosiin showed dose-dependent response in concentration range of o.oo1-5 µM and 1-20 µM, respectively, in biological studies beneficial to diabetes. Particularly, rhoifolin and cosmosiin at 0.5 and 20 µM, respectively showed nearly similar response to that 10 nM of insulin, on adiponectin secretion level. Furthermore, 5 µM of rhoifolin and 20 µM of cosmosiin showed equal potential with 10 nM of insulin to increase the phosphorylation of insulin receptor-ß, in addition to their positive effect on GLUT4 translocation. These findings indicate that rhoifolin and cosmosiin from red wendun leaves may be beneficial for diabetic complications through their enhanced adiponectin secretion, tyrosine phosphorylation of insulin receptor-ß and GLUT4 translocation.

12.
J Ethnopharmacol ; 131(2): 363-7, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20633630

RESUMO

AIM OF THE STUDY: The purpose of this study is to isolate the pure compounds from the extracts of Cordyceps militaris obtained through solid-state cultivation process, and evaluate their anti-inflammatory and anticancer properties. MATERIALS AND METHODS: Silica gel column chromatographic purification of Cordyceps militaris extracts resulted in the isolation of 10 pure compounds (1-10). The compounds 1-10 were examined for their growth inhibitory properties against nitric oxide (NO), tumor necrosis factor (TNF)-alpha and interleukin (IL)-12 enhanced production from LPS/IFN-gamma-stimulated macrophages. Additionally, the anti-proliferation effects of 1-10 on human cancer cell lines, colon (colon 205), prostate (PC-3), and hepatoma (HepG2) cells were also analyzed. RESULTS: Compound 8 displayed potent growth inhibition on NO, TNF-alpha and IL-12 production with an IC(50) value of 7.5, 6.3, and 7.6 microg/ml, respectively. A similar inhibitory trend on these inflammatory mediators was observed for 3, 7, 9 and 10 with an IC(50) values ranging from 10.8 to 17.2 microg/ml. On the other hand, compounds 3 and 8 were potent anti-proliferative agents with an IC(50) value of 35.6 and 32.6 microg/ml toward PC-3 and colon 205 cell lines, respectively. The compounds 1 and 2 showed potent anti-proliferation in PC-3 and colon 205 cells, while only 3 displayed such effect in HepG2 cells. CONCLUSION: The present study provides scientific supporting information for the ethnopharmacological use of Cordyceps militaris as an anti-inflammatory and anticancer agent.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Cordyceps/química , Mediadores da Inflamação/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Interferon gama , Interleucina-12/antagonistas & inibidores , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Neoplasias/metabolismo , Óxido Nítrico/antagonistas & inibidores , Fitoterapia , Fator de Necrose Tumoral alfa/antagonistas & inibidores
13.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): o920, 2010 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-21580730

RESUMO

In the crystal structure of the title compound, C(11)H(15)N(3)O(3), mol-ecules are linked into a chain by inter-molecular N-H⋯O hydrogen bonds.

14.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2206, 2010 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-21588578

RESUMO

The mol-ecule of the title compound, C(12)H(16)N(2)O(4), is located on an inversion center. The carboxyl-ate groups are twisted slightly with respect to the pyrazine ring, making a dihedral angle of 6.4 (3)°.

15.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): o2367, 2009 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-21577833

RESUMO

The title compound, C(12)H(9)N(2)O(2) (+)·Cl(-)·2H(2)O, exhibits a layered structure which is stabilized by inter-molecular O-H⋯O, O-H⋯Cl(-) and N(+)-H⋯Cl(-) hydrogen bonds, and π-π inter-actions (centroid-centroid distances = 3.654 and 3.583 Å). The distances between the molecules are 3.371 and 3.294 Å.

16.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 4): o677, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21202070

RESUMO

In the title compound, C(12)H(16)N(6)O(2)·2H(2)O, the organic mol-ecule, except for the methyl H atoms, is essentially planar, the r.m.s. deviation from planarity being 0.044 Å. The crystal structure is stabilized by inter-molecular O-H⋯O and O-H⋯N hydrogen bonds which form chains.

17.
Inorg Chem ; 46(19): 7910-6, 2007 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-17696493

RESUMO

Two new compounds, [Ph3PCH2Ph]2[Zn3(tp)3Cl2] (1) and Ni3(tma)2(H2O)8 (2) (tp = terephthalate, tma = trimesate), are metal-polycarboxylate coordination polymers prepared by similar hydrothermal synthesis techniques. X-ray single-crystal structural analysis shows that both compounds crystallize in the 2D claylike lamellar architectures, in which 1 possesses the interlayer [Ph3PCH2Ph]+ exchangeable cation and has been confirmed by PXRD patterns. 1 (C74H56Cl2O12P2Zn3) belongs to monoclinic P21/c, Z = 2 (a = 18.956(1) A, b = 10.2697(5) A, c = 17.067(1) A, beta = 99.486(4) degrees ). 2 (C18H22O20Ni3) is attributed to triclinic P, Z = 1 (a = 6.6643(8) A, b = 9.622(1) A, c = 10.089(1) A, alpha = 112.675(2) degrees , beta = 94.007(1) degrees, gamma = 106.411(2) degrees ). Linear metal trinuclear clusters bridged by rigid linear tp ligands for 1 and trigonal tma ligands for 2 give rise to a novel 2D 6-linked (3,6) topological anionic network in 1 and an interesting 2D 3,6-linked molybdenite topological neutral network in 2, respectively. Both compounds exhibit intense fluorescent emission bands at 410 nm (lambda(exc) = 355 nm) for 1 and 398 nm (lambda(exc) = 300 nm) for 2 in the solid state at room temperature.

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