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1.
Food Funct ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023128

RESUMO

Miao sour soup (MSS), a daily fermented food in Guizhou, China, is rich in microorganisms with various beneficial activities, including anti-inflammatory and antioxidant activities. However, the therapeutic effects of MSS on IBD remain unexplored. This study aimed to investigate the protective effect of MSS against colitis in mice. In this study, we examined the microbial community structure of MSS by metagenomic sequencing and also explored the protective effect of MSS on DSS-induced colitis in mice. We investigated the effects of MSS on intestinal inflammatory response and intestinal barrier function in mice. Finally, the changes in intestinal flora were analyzed based on the 16S rRNA gene sequencing results. Significantly, the experiment result shows that MSS ameliorated the severity of DSS-induced disease in mice by mitigating colitis-associated weight loss, reducing the disease activity index of IBD, alleviating colonic hemorrhagic lesions, increasing colon length, and improving colonic tissue damage. Moreover, MSS preserved intestinal barrier integrity and restored intestinal epithelial function in mice. Additionally, MSS modulated the structure and composition of the intestinal flora. Furthermore, MSS downregulated pro-inflammatory factors and attenuated the NF-κB p65 expression, thereby mitigating the inflammatory response. These findings highlight the protective effect of MSS against DSS-induced colitis, providing substantial scientific support for potential applications of MSS as a functional food.

2.
Plants (Basel) ; 12(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36903855

RESUMO

The AP2/ERF gene family is one of the most conserved and important transcription factor families mainly occurring in plants with various functions in regulating plant biological and physiological processes. However, little comprehensive research has been conducted on the AP2/ERF gene family in Rhododendron (specifically, Rhododendron simsii), an important ornamental plant. The existing whole-genome sequence of Rhododendron provided data to investigate the AP2/ERF genes in Rhododendron on a genome-wide scale. A total of 120 Rhododendron AP2/ERF genes were identified. The phylogenetic analysis showed that RsAP2 genes were classified into five main subfamilies, AP2, ERF, DREB, RAV and soloist. Cis-acting elements involving plant growth regulators, response to abiotic stress and MYB binding sites were detected in the upstream sequences of RsAP2 genes. A heatmap of RsAP2 gene expression levels showed that these genes had different expression patterns in the five developmental stages of Rhododendron flowers. Twenty RsAP2 genes were selected for quantitative RT-PCR experiments to clarify the expression level changes under cold, salt and drought stress treatments, and the results showed that most of the RsAP2 genes responded to these abiotic stresses. This study generated comprehensive information on the RsAP2 gene family and provides a theoretical basis for future genetic improvement.

3.
Mol Biol Rep ; 49(4): 2641-2653, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35059966

RESUMO

BACKGROUND: Rhododendron is an important woody ornamental plant, and breeding varieties with different colors is a key research goal. Although there have been a few reports on the molecular mechanisms of flower colors and color patterning in Rhododendron, it is still largely unknown what factors regulate flower pigmentation in Rhododendron. METHODS AND RESULTS: In this study, the flower color variation cultivar 'Yanzhi Mi' and the wild-type (WT) cultivar 'Dayuanyangjin' were used as research objects, and the pigments and transcriptomes of their petals during five flower development stages were analyzed and compared. The results showed that derivatives of cyanidin, peonidin and pelargonidin might be responsible for the pink color of mutant petals and that the S2 stage was the key stage of flower color formation. In total, 412,910 transcripts and 2780 differentially expressed genes (DEGs) were identified in pairwise comparisons of WT and mutant petals. GO and KEGG enrichment analyses of the DEGs showed that 'DNA-binding transcription factor activity', 'Flavonoid biosynthesis' and 'Phenylpropanoid biosynthesis' were more active in mutant petals. Early anthocyanin pathway candidate DEGs (CHS3-CHS6, CHI, F3Hs and F3'H) were significantly correlated and were more highly expressed in mutant petals than in WT petals in the S2 stage. An R2R3-MYB unigene (TRINITY_DN55156_c1_g2) was upregulated approximately 10.5-fold in 'Yanzhi Mi' petals relative to 'Dayuanyangjin' petals in the S2 stage, and an R2R3-MYB unigene (TRINITY_DN59015_c3_g2) that was significantly downregulated in 'Yanzhi Mi' petals in the S2 stage was found to be closely related to Tca MYB112 in cacao. CONCLUSIONS: Taken together, the results of the present study could shed light on the molecular basis of anthocyanin biosynthesis in two Rhododendron obtusum cultivars and may provide a genetic resource for breeding varieties with different flower colors.


Assuntos
Rhododendron , Flores/genética , Flores/metabolismo , Perfilação da Expressão Gênica , Pigmentação/genética , Melhoramento Vegetal , Rhododendron/genética
4.
Angew Chem Int Ed Engl ; 57(41): 13635-13639, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30152145

RESUMO

Porous curved polycyclic aromatic compounds 6 and 14 bearing a tribenzotriquinacene (TBTQ) core encircled by an m,p,p,m,m,p,p,m,m,p,p,m-cyclododecaphenylene belt were synthesized and characterized by NMR spectroscopy and mass spectrometry. These trefoil hydrocarbon macrocycles were constructed in high yield using an intramolecular three-fold Scholl macrocyclization. X-ray crystal analysis of 14 demonstrated a large wizard-hat-shaped structure with three pores (radii 2.9-3.0 Å). The π-stacking aggregation of the hexa-n-dodecyloxy derivative 6 a and the chloride anion binding properties of 14 were studied by NMR spectroscopy. Such stacking and anion binding properties were much weaker in the singly 11 and doubly macrocyclized products 12.

5.
Life Sci ; 207: 428-435, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29966606

RESUMO

AIM: The present study aims to investigate the pharmacokinetics and pharmacodynamics of HLS-3, a tacrine dimer with high anti-acetylcholinesterase activity for the treatment of Alzheimer's disease. MAIN METHODS: In vitro Calu-3 and Caco-2 cell monolayer transport and liver microsomal incubation studies of HLS-3 were carried out to evaluate its nasal epithelium and intestinal membrane permeability, transporters involved in absorption and hepatic metabolism. In vivo pharmacokinetics of HLS-3 followed by central and peripheral cholinergic mediated responses and ex vivo AChE activities in rats via oral and intranasal administrations were further investigated and compared. KEY FINDINGS: Our in vitro studies suggested that HLS-3 is the substrate of both P-gp and MRPs with no significant hepatic oxidation and glucuronidation metabolism. Oral administration only delivered trace amount of HLS-3 in systemic circulation with a high faecal recovery of 70.7%, whereas intranasal administration demonstrated an absolute bioavailability of 28.9% with urinary and faecal recoveries of 1.5% and 34.0%, respectively. In comparison to oral administration of HLS-3, intranasally delivered HLS-3 exhibited significant higher central cholinergic mediated responses without obvious peripheral side effect. SIGNIFICANCE: Intranasal delivery of HLS-3 with better pharmacokinetics and pharmacodynamics performances provides a promising approach for treatment of Alzheimer's disease.


Assuntos
Acetilcolinesterase/química , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/administração & dosagem , Tacrina/análogos & derivados , Tacrina/farmacologia , Administração Intranasal , Administração Oral , Animais , Área Sob a Curva , Células CACO-2 , Linhagem Celular , Sobrevivência Celular , Inibidores da Colinesterase/farmacocinética , Inibidores da Colinesterase/farmacologia , Dimerização , Desenho de Fármacos , Epitélio/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Microssomos Hepáticos/metabolismo , Ratos , Tacrina/química
6.
Genes Genomics ; 40(6): 591-601, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29892944

RESUMO

Rhododendron molle G. Don occupies an important phylogenetic node in the genus rhododendron with unique yellow flower and medicinal functions. However, only limited genetic resources and their genome information are available for the generation of rhododendron flowers. The next generation sequencing technologies enables generation of genomic resources in a short time and at a minimal cost, and therefore provide a turning point for rhododendron research. Our goal is to use the genetic information to facilitate the relevant research on flowering and flower color formation in R. molle. In total, 66,026 unigenes were identified, among which 31,298 were annotated in the NCBI non-redundant protein database and 22,410 were annotated in the Swiss-Prot database. Of these annotated unigenes, 9490 and 18,680 unigenes were assigned to clusters of orthologous groups and gene ontology categories, respectively. A total of 7177 genes were mapped to 118 pathways using the Kyoto Encyclopedia of Genes and Genomes Pathway database. In addition, 8266 simple sequence repeats (SSRs) were detected, and these SSRs will undoubtedly benefit rhododendron breeding work. Metabolic pathway analysis revealed that 32 unigenes were predicted to be involved in carotenoid biosynthesis. Our transcriptome revealed 32 engines that encode key enzymes in the carotenoid biosynthesis pathway, including PSY, PDS, LCYB, LCYE, etc. The content of ß-carotene was much higher than the other carotenoids throughout the flower development. It was consistent with the key genes expression level in the carotenoid biosynthesis pathway by the Illumina expression profile analysis and the qRT-PCR analysis. Our study identified genes associated with carotenoid biosynthesis in R. molle and provides a valuable resource for understanding the flowering and flower color formation mechanisms in R. molle.


Assuntos
Perfilação da Expressão Gênica/métodos , Rhododendron/genética , Carotenoides/biossíntese , Flores/genética , Ontologia Genética , Genes de Plantas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas/genética , Repetições de Microssatélites/genética , Anotação de Sequência Molecular/métodos , Filogenia , Análise de Sequência de DNA , Transcriptoma/genética
7.
Org Lett ; 20(6): 1676-1679, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29489379

RESUMO

A new method for the synthesis of 2-(trifluoromethyl)indoles using easily accessible 2-alkynylanilines and a well-established fluoroform-derived CuCF3 reagent is described. This method utilizes a domino trifluoromethylation/cyclization strategy to construct the indole cores with no ambiguity of the CF3 position. The intriguing 3-formyl-2-(trifluoromethyl)indoles can also be synthesized by this protocol, which are useful intermediates for the preparation of trifluoromethylated drug analogues. The ultimate CF3 source is the inexpensive industrial byproduct fluoroform.

8.
J Org Chem ; 82(12): 6192-6201, 2017 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-28523912

RESUMO

A domino hydroboration/trifluoromethylation (formal hydrotrifluoromethylation) of alkynes using the fluoroform-derived [CuCF3] reagent is achieved. Synthetically useful (E)-alkenyl-CF3 building blocks and 1,1-bis(trifluoromethyl)-substituted alkenes can be prepared under ambient conditions in one pot/one step from alkynes. The ultimate source of CF3 is the inexpensive industrial waste fluoroform.

9.
Org Lett ; 19(9): 2446-2449, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28440653

RESUMO

Hydroxytrifluoromethylation of alkenes using the fluoroform (CF3H)-derived [CuCF3] reagent is described. In the presence of additive B2Pin2 and air, this reagent effectively facilitates the addition of hydroxy and trifluoromethyl groups across an alkene double bond, a formal hydroxytrifluoromethylation process. Various ß-trifluoromethyl alcohols can be synthesized from simple alkenes where the ultimate CF3 source is the industrial byproduct fluoroform.

10.
Org Lett ; 19(3): 658-661, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28080073

RESUMO

A copper-mediated synthesis of 4-(trifluoromethyl)pyrazoles is described. In one step from readily accessible α,ß-alkynic tosylhydrazones, a remarkable domino sequence of cyclization, trifluoromethylation, and detosylation takes place to furnish the 4-CF3 N-H pyrazole cores with good functional group compatibility. The reaction conditions are mild and convenient, at room temperature in air, using the commercially available trifluoromethyltrimethylsilane (TMSCF3) as the CF3 source. The method can be applied to the synthesis of a 4-CF3 analogue of the anti-inflammatory drug celecoxib.

11.
Front Plant Sci ; 7: 1547, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27803707

RESUMO

The quantitative real-time polymerase chain reaction (qRT-PCR) approach has become a widely used method to analyze expression patterns of target genes. The selection of an optimal reference gene is a prerequisite for the accurate normalization of gene expression in qRT-PCR. The present study constitutes the first systematic evaluation of potential reference genes in Rhododendron molle G. Don. Eleven candidate reference genes in different tissues and flowers at different developmental stages of R. molle were assessed using the following three software packages: GeNorm, NormFinder, and BestKeeper. The results showed that EF1-α (elongation factor 1-alpha), 18S (18s ribosomal RNA), and RPL3 (ribosomal protein L3) were the most stable reference genes in developing rhododendron flowers and, thus, in all of the tested samples, while tublin (TUB) was the least stable. ACT5 (actin), RPL3, 18S, and EF1-α were found to be the top four choices for different tissues, whereas TUB was not found to favor qRT-PCR normalization in these tissues. Three stable reference genes are recommended for the normalization of qRT-PCR data in R. molle. Furthermore, the expression profiles of RmPSY (phytoene synthase) and RmPDS (phytoene dehydrogenase) were assessed using EF1-α, 18S, ACT5, RPL3, and their combination as internals. Similar trends were found, but these trends varied when the least stable reference gene TUB was used. The results further prove that it is necessary to validate the stability of reference genes prior to their use for normalization under different experimental conditions. This study provides useful information for reliable qRT-PCR data normalization in gene studies of R. molle.

12.
Org Lett ; 18(12): 2800-3, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27258390

RESUMO

An efficient trifluoromethylation reaction of alkynes using a fluoroform-derived CuCF3 reagent is described. The CF3 source is the inexpensive industrial waste fluoroform (CF3H). The air-stable CuCF3 reagent can be prepared in large quantities and is convenient to use. Synthetically useful trifluoromethylated alkynes containing a wide range of functional groups were successfully synthesized under mild conditions. Both terminal and TMS-protected alkynes gave the products in one step. The beneficial effect of a diamine ligand tetramethylethylenediamine (TMEDA) with the fluoroform-derived CuCF3 reagent was also demonstrated.

13.
Angew Chem Int Ed Engl ; 54(15): 4512-6, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25655138

RESUMO

An asymmetric tail-to-tail cross-hydroalkenylation of vinylarenes with terminal olefins was achieved by catalysis with NiH complexes bearing chiral N-heterocyclic carbenes (NHCs). The reaction provides branched gem-disubstituted olefins with high enantioselectivity (up to 94 % ee) and chemoselectivity (cross/homo product ratio: up to 99:1). Electronic effects of the substituents on the vinylarenes and on the N-aryl groups of the NHC ligands, but not a π,π-stacking mechanism, assist the steric effect and influence the outcome of the cross-hydroalkenylation.

14.
Int J Pharm ; 477(1-2): 442-53, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25445524

RESUMO

Tacrine (THA), as the first approved acetylcholinesterase (AChE) inhibitors for the treatment of Alzheimer's disease (AD), has been extensively investigated in last seven decades. After dimerization of THA via a 7-carbon alkyl spacer, bis(7)-tacrine (B7T) showed much potent anti-AChE activity than THA. We here report synthesis, biological evaluation and biopharmaceutical characterization of six THA dimers referable to B7T. According to IC50 values, the in vitro anti-AChE activities of THA dimers were up to 300-fold more potent and 200-fold more selective than that of THA. In addition, the anti-AChE activities of THA dimers were found to be associated with the type and length of the linkage. All studied THA dimers showed much lower cytotoxicity than B7T, but like B7T, they demonstrated much lower absorptive permeabilities than that of THA on Caco-2 monolayer model. In addition, all THA dimers demonstrated significant efflux transport (efflux ratio >4), indicating that the limited permeability could be associated with the efflux transport during absorption process. Moreover, the dimer with higher Log P value was accompanied with higher permeability but lower aqueous solubility. A balanced consideration of activity, solubility, cytotoxicity and permeability should be conducted in selection of the potential candidates for further in vivo investigation.


Assuntos
Biofarmácia/métodos , Inibidores da Colinesterase/síntese química , Tacrina/análogos & derivados , Transporte Biológico , Células CACO-2 , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacocinética , Inibidores da Colinesterase/toxicidade , Cromatografia Líquida de Alta Pressão , Dimerização , Humanos , Estrutura Molecular , Solubilidade , Tacrina/síntese química , Tacrina/química , Tacrina/farmacocinética , Tacrina/toxicidade , Espectrometria de Massas em Tandem
15.
J Org Chem ; 79(24): 11873-84, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24802364

RESUMO

This paper describes a new approach in transition-metal-catalyzed unsymmetric cycloisomerization for medium-sized heterocycles. The steric and electronic effects of an NHC-NiH catalyst and γ-heteroatom chelation were used together as a basis for 1,n-diene termini differentiation and for n(γ)-exo-trig (head-to-tail) product selectivity. Heterocycles bearing an exocyclic methylene such as oxepines, thiepines, siloxepines, and oxocanes were synthesized from the corresponding 1,n-dienes by a fine-tuning of the NHC properties. The implication of the underlying hypothesis was further demonstrated in a competition experiment in which strained oxepines were formed preferentially over other competing oxa-/carbocycles. Under more forcing physical conditions and the use of a suitable NHC ligand, the exocyclic methylene products were isomerized further into endocyclic olefin products regioselectively in one pot.

16.
Chem Commun (Camb) ; 48(10): 1481-3, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22116100

RESUMO

Via a cooperation of NHC, Si substituents and a M center, ß-Si elimination was attenuated, revealing a new way to attain a high Ni-ß-SiR(3):Ni-σ-SiR(3) ratio. The scope is illustrated by a head-to-tail vinylsilane-α-olefin hydroalkenylation.


Assuntos
Compostos Heterocíclicos/química , Metano/análogos & derivados , Níquel/química , Compostos Organometálicos/síntese química , Silanos/química , Metano/química , Estrutura Molecular , Compostos Organometálicos/química , Estereoisomerismo
17.
Dalton Trans ; 39(46): 11171-9, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-20967343

RESUMO

M(2)L(2) type metallacyclic complexes, [Pd(2)(L1)(2)Cl(4)]·1.5CH(2)Cl(2) (1), [Pd(2)(L1)(2)Cl(4)]·2CHCl(3) (2), [Pd(2)(L2)(2)Cl(4)]·2CH(2)Cl(2)·2CH(3)CN (3), [Pd(2)(L2)(2)Cl(4)]·2CHCl(3)·2CH(3)CN (4) and [Pd(2)(L3)(2)Cl(4)]·CH(2)Cl(2)·2CH(3)CN (5), have been prepared from three semi-rigid benzimidazol or benzotriazol ligands, 1,4-bis(benzimidazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene (L1), 1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene (L2) and 1,4-bis(benzotriazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene (L3). All the complexes were structurally characterized by single-crystal X-ray diffraction and the phase purity was confirmed by powder X-ray diffraction (PXRD) measurements. The solution structure of representative complex 1 was studied by (1)H NMR titration and ESI mass spectroscopy. The thermal stability and guest-exchange properties of 1, 3 and 4 were investigated, revealing that the Pd(2)L(2) metallacycles can act as a selective receptor for CH(2)Cl(2) or CHCl(3) guest molecules. The catalytic activity of 1 in Suzuki-Miyaura coupling reaction was also studied and 1 could be recycled at least 5 times under heterogeneous conditions, indicative of a potential self-supported catalyst.

19.
ACS Appl Mater Interfaces ; 2(8): 2333-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20735105

RESUMO

Functional nanoscale coordination polymers are receiving growing scientific interest because of their potential applications in many domains. In this paper, we demonstrated that a nanofibrous networked metal-organic gel (G1-MNPs) was formed by simply mixing 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tris(N-(pyridin-3-ylmethyl)benzamide) (L) and Pd(COD)(NO(3))(2) in CHCl(3)-MeOH with a Pd/L molar ratio of 1:1 in the presence of magnetite nanoparticle (MNPs). The self-assembly behavior of nanofibers was not significantly effected by the introduction of magnetite nanoparticles. The xerogel of G1-MNPs was superparamagnetic and showed catalytic activity in Suzuki-Miyaura C-C coupling reactions. The Pd(II) xerogel could be magnetically isolated and recycled with a permanent magnet. It represents a novel strategy to introduce nanoparticles into functional coordination polymers for multifunctional materials.


Assuntos
Biotecnologia/métodos , Sistemas de Liberação de Medicamentos/métodos , Óxido Ferroso-Férrico/química , Nanofibras/química , Polímeros/química , Carbono/química , Catálise , Géis/química , Paládio/química
20.
Mol Biol Rep ; 37(2): 995-1001, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19728144

RESUMO

A new Lycoris radiata pathogenesis-related (PR)-4 gene, LrPR4 was isolated. LrPR4 encodes a 142 amino acid protein with a predicted molecular mass of 15.43 kDa and pI of 7.56. The putative LrPR4 shows high similarity to PR4 type proteins from various plant species and belongs to the Barwin family. Like other PR4s from monocot plants, LrPR4 protein contains a conserved Barwin domain and has a signal peptide at its N-terminus. The recombinant LrPR4 protein expressed in Escherichia coli showed activity towards hydrolysing RNA from L. radiata bulbs and antifungal activity. The results of this study suggest that LrPR4 may play a role in the disease resistance responses of plant against pathogen attacks though its antifungal activity.


Assuntos
Antifúngicos/farmacologia , Lycoris/genética , Magnaporthe/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Clonagem Molecular , DNA Complementar/isolamento & purificação , Avaliação de Medicamentos , Interações Hospedeiro-Patógeno/genética , Imunidade Inata/genética , Lycoris/imunologia , Magnaporthe/imunologia , Modelos Moleculares , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/prevenção & controle , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Análise de Sequência de DNA
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