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1.
Environ Res ; 252(Pt 1): 118839, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38570131

RESUMO

Weeds pose multifaceted challenges in rice cultivation, leading to substantial economic losses through reduced yield and poor grain quality. Harnessing the natural genetic diversity in germplasm collections becomes crucial for identifying novel herbicide resistance loci in crops. A comprehensive analysis was conducted on 475 rice accessions from the KRICE depository, assessing their response to TFT (tefuryltrione) and probing the underlying HIS1 (HPPD INHIBITOR SENSITIVE 1) genotypic variations. The HIS1 gene, responsible for detoxifying benzobicyclon (BBC) and imparting broad-spectrum herbicide resistance, holds significant promise in rice breeding. This study explores the genetic landscape of HIS1 within Korean rice collection (KRICE), aiming to unveil genetic variations, haplotype diversity, and evolutionary relationships across diverse rice ecotypes. The indica ecotype showed the highest nucleotide diversity, while the wild and temperate japonica groups exhibited low diversity, hinting at selective sweeps and possible population expansion. Negative Tajima's D values in temperate japonica and wild groups indicate an excess of low-frequency mutations, potentially resulting from selective sweeps. In contrast, with positive Tajima's D values, admixture, indica, and aus groups suggest balancing selection. Furthermore, haplotype analysis uncovered 42 distinct haplotypes within KRICE, with four shared haplotypes between cultivated and wild accessions, four specific to cultivated accessions, and 34 specific to wild types. Phenotypic assessments of these haplotypes revealed that three haplotypes, viz., Hap_1 (predominant in japonica), Hap_2 (predominant in indica), and Hap_3 (specific to indica), displayed significant differences from aus-specific Hap_4 and indica-specific Hap_5. This study offers insights into genetic diversity, selective pressures, and ecotype-specific responses, ultimately paving the way for developing HPPD-inhibiting herbicide-resistant rice cultivars.


Assuntos
Variação Genética , Haplótipos , Herbicidas , Oryza , Oryza/genética , Resistência a Herbicidas/genética , Evolução Molecular
2.
Int J Mol Sci ; 20(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652855

RESUMO

The aim of this study was to evaluate the pharmacological efficacy of persimmon leaves in two glaucoma models, microbeads-induced ocular hypertension (OHT) and DBA/2 mouse. Thus, we demonstrated that Ethanol Extract of Diospyros kaki (EEDK) reduced elevated intraocular pressure (IOP) in both mouse models of glaucoma by measurements with a tonometer. In particular, we revealed that retinal ganglion cell loss and optic nerve damage caused by IOP elevation were markedly diminished as assessed by TUNEL assay, H&E staining, and fluorescent staining, while the expression of soluble guanylate cyclase (sGCα-1) increased, when EEDK was administered, as revealed by western blot. Moreover, the b-wave magnitude indicating functional scotopic vision was significantly improved in EEDK-administered DBA/2 mice during the 10-week follow-up study, as observed with electroretinography. Collectively, our results suggested that EEDK could be an effective therapeutic and IOP-lowering agent for preventing and treating retinal degenerative diseases such as glaucoma.


Assuntos
Diospyros/química , Glaucoma/tratamento farmacológico , Pressão Intraocular , Extratos Vegetais/uso terapêutico , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nervo Óptico/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/metabolismo , Guanilil Ciclase Solúvel/metabolismo
3.
J Cell Biochem ; 119(1): 260-268, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28513976

RESUMO

During the early stages of atherosclerosis, monocytes bind and migrate into the endothelial layer, promoting inflammation within the aorta. In order to prevent the development of atherosclerosis, it is critical to inhibit such inflammation. The therapeutic effects of ginger have been investigated in several models of cardiovascular disease. However, although a number of previous studies have focused on specific compounds, the mechanisms of action responsible remain unclear. Here, we investigated five major compounds present in ginger, and observed that gingerenone A exhibited the strongest inhibitory effects against tumor necrosis factor (TNF)-α and lipopolysaccharide (LPS) induced monocyte-endothelial adhesion. Furthermore, gingerenone A significantly suppressed the expression of TNF-α and LPS-induced vascular cell adhesion molecule-1 (VCAM-1) and chemokine (C-C motif) ligand 2 (CCL2), key mediators of the interaction between monocytes, and endothelial cells. Transactivation of nuclear factor-κB (NF-κB), which is a key transcription factor of VCAM-1 and CCL2, was induced by TNF-α and LPS, and inhibited by treatment of gingerenone A. Gingerenone A also inhibited the phosphorylation of NF-κB inhibitor (IκB) α and IκB Kinase. Taken together, these results demonstrate that gingerenone A attenuates TNF-α and LPS-induced monocyte adhesion and the expression of adhesion factors in endothelial cells via the suppression of NF-κB signaling. J. Cell. Biochem. 119: 260-268, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Diarileptanoides/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Quinase I-kappa B/metabolismo , Monócitos/metabolismo , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CCL2/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Lipopolissacarídeos/toxicidade , Monócitos/citologia , Fosforilação/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
4.
Exp Dermatol ; 27(5): 449-452, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28453925

RESUMO

The soy isoflavone daidzein is bioconverted to 7,8,4'-trihydroxyisoflavone (7,8,4'-THIF) by microorganisms. Here, we investigated the matrix metalloproteinase (MMP)-1 inhibitory properties of 7,8,4'-THIF that arise through the suppression of UVB-induced MMP-1 expression. 7,8,4'-THIF reduced UVB-induced MMP-1 expression at the transcriptional level in primary human dermal fibroblasts and inhibited UVB-induced transcriptional activity of AP-1, a major activator of MMP-1 expression. Additionally, it was observed that the mitogen-activated protein kinase (MAPK) pathway, a crucial signalling cascade for MMP-1 expression, was suppressed by 7,8,4'-THIF. Protein kinase C iota (PKCι) was suspected to be a direct target of 7,8,4'-THIF. The direct interaction between 7,8,4'-THIF and PKCι was confirmed using pull-down assays and immobilized metal ion affinity-based fluorescence polarization assays. Finally, we observed that 7,8,4'-THIF inhibited UVB-induced MMP-1 expression in a human skin equivalent model. Taken together, these results suggest that 7,8,4'-THIF, a bioconversion product of daidzein, suppresses UVB-induced MMP-1 expression.


Assuntos
Isoenzimas/antagonistas & inibidores , Isoflavonas/farmacologia , Metaloproteinase 1 da Matriz/metabolismo , Proteína Quinase C/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , Humanos , Envelhecimento da Pele/efeitos dos fármacos , Raios Ultravioleta
5.
Bioorg Med Chem ; 26(21): 5701-5710, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30366787

RESUMO

The hormone glucagon increases blood glucose levels through increasing hepatic glucose output. In diabetic patients, dysregulation of glucagon secretion contributes to hyperglycemia. Thus, the inhibition of glucagon receptor is one target for the treatment of hyperglycemia in type 2 diabetes. Here we designed and synthesized a series of small molecules based on phenylpyrimidine. Of these, the compound (R)-7a most significantly decreased the glucagon-induced cAMP production and glucagon-induced glucose production during in vitro and in vivo assays. In addition, (R)-7a showed good efficacy in glucagon challenge tests and lowered blood glucose levels in diabetic db/db mice. Our results suggest that the compound (R)-7a could be a potential glucose-lowering agent for treating type 2 diabetes.


Assuntos
Hipoglicemiantes/uso terapêutico , Pirimidinas/uso terapêutico , Receptores de Glucagon/antagonistas & inibidores , Animais , Glicemia/análise , Glicemia/metabolismo , Células CHO , Cricetulus , AMP Cíclico/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Hepatócitos/efeitos dos fármacos , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/toxicidade , Masculino , Camundongos Endogâmicos C57BL , Pirimidinas/síntese química , Pirimidinas/farmacocinética , Pirimidinas/toxicidade , Estereoisomerismo
6.
Int J Mol Sci ; 18(7)2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28672844

RESUMO

Several metabolomics of polymeric flavan-3-ols have reported that proanthocyanidins are extensively metabolized by gut microbiota. 5-(3',4'-dihydroxyphenyl)-γ-valerolactone (DHPV) has been reported to be the major microbial metabolite of proanthocyanidins. We demonstrated that DHPV has stronger prevention effect on tumor necrosis factor (TNF)-α-stimulated adhesion of THP-1 human monocytic cells to human umbilical vein endothelial cells compared to its potential precursors such as procyanidin A1, A2, B1 and B2, (+)catechin, (-)epicatechin and its microbial metabolites such as 3-(3,4-dihydroxyphenyl)propionic acid and 2-(3,4-dihydroxyphenyl)acetic acid. Mechanism study showed that DHPV prevents THP-1 monocyte-endothelial cell adhesion by downregulating TNF-α-stimulated expressions of the two biomarkers of atherosclerosis such as vascular cell adhesion molecule-1 and monocyte chemotactic protein-1, activation of nuclear factor kappa B transcription and phosphorylation of I kappa-B kinase and IκBα. We suggested that DHPV has higher potentiality in prevention of atherosclerosis among the proanthocyanidin metabolites.


Assuntos
Adesão Celular/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Células Endoteliais/metabolismo , Monócitos/metabolismo , Proantocianidinas/farmacologia , Linhagem Celular , Células Endoteliais/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Redes e Vias Metabólicas , Monócitos/imunologia , NF-kappa B/genética , NF-kappa B/metabolismo , Fosforilação , Proantocianidinas/metabolismo , Regiões Promotoras Genéticas , Substâncias Protetoras , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
7.
BMC Genomics ; 17: 408, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27229151

RESUMO

BACKGROUND: Rice germplasm collections continue to grow in number and size around the world. Since maintaining and screening such massive resources remains challenging, it is important to establish practical methods to manage them. A core collection, by definition, refers to a subset of the entire population that preserves the majority of genetic diversity, enhancing the efficiency of germplasm utilization. RESULTS: Here, we report whole-genome resequencing of the 137 rice mini core collection or Korean rice core set (KRICE_CORE) that represents 25,604 rice germplasms deposited in the Korean genebank of the Rural Development Administration (RDA). We implemented the Illumina HiSeq 2000 and 2500 platform to produce short reads and then assembled those with 9.8 depths using Nipponbare as a reference. Comparisons of the sequences with the reference genome yielded more than 15 million (M) single nucleotide polymorphisms (SNPs) and 1.3 M INDELs. Phylogenetic and population analyses using 2,046,529 high-quality SNPs successfully assigned rice accessions to the relevant rice subgroups, suggesting that these SNPs capture evolutionary signatures that have accumulated in rice subpopulations. Furthermore, genome-wide association studies (GWAS) for four exemplary agronomic traits in the KRIC_CORE manifest the utility of KRICE_CORE; that is, identifying previously defined genes or novel genetic factors that potentially regulate important phenotypes. CONCLUSION: This study provides strong evidence that the size of KRICE_CORE is small but contains high genetic and functional diversity across the genome. Thus, our resequencing results will be useful for future breeding, as well as functional and evolutionary studies, in the post-genomic era.


Assuntos
Cruzamento , Evolução Molecular , Genoma de Planta , Estudo de Associação Genômica Ampla , Genômica/métodos , Oryza/genética , Análise de Sequência de DNA , Variação Genética , Genética Populacional , Mutação INDEL , Polimorfismo de Nucleotídeo Único
8.
Mol Carcinog ; 55(5): 552-62, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25787879

RESUMO

Bioactive natural compounds from plant-derived sources have received substantial interest due to their potential therapeutic and preventive effects toward various human diseases. Licorice (Glycyrrhiza), a frequently-used component in traditional oriental medicines, has been incorporated into recipes not only to enhance taste, but also to treat various conditions including inflammation, chronic fatigue syndrome, and even cancer. Dehydroglyasperin C (DGC) is a major isoflavone found in the root of licorice. In the present study, we investigated the cancer chemopreventive effect of DGC and the underlying molecular mechanisms involved, by analyzing its effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced neoplastic cell transformation and cyclooxygenase (COX)-2 expression in JB6 P+ mouse epidermal cells. DGC treatment attenuated TPA-induced activator protein-1 (AP-1) and nuclear factor-κB (NF-κB) transcriptional activation, two major regulators of TPA-induced cell transformation, and COX-2 expression. TPA-induced phosphorylation of p38, JNK1/2 and Akt was also suppressed by DGC. Kinase assay data revealed that DGC inhibited the kinase activity of MKK4 and PI3K and this outcome was due to direct physical binding with DGC. Notably, DGC bound directly to MKK4 and PI3K in an ATP-competitive manner. Taken together, these results suggest that DGC exhibits cancer chemopreventive potential via its inhibitory effect on TPA-induced neoplastic cell transformation and COX-2 modulation through regulation of the MKK4 and PI3K pathways.


Assuntos
Benzopiranos/farmacologia , Carcinógenos/toxicidade , Transformação Celular Neoplásica/efeitos dos fármacos , MAP Quinase Quinase 4/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Acetato de Tetradecanoilforbol/toxicidade , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/metabolismo , Ciclo-Oxigenase 2/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , NF-kappa B/metabolismo , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo
9.
Bioorg Med Chem Lett ; 26(20): 4907-4910, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27666633

RESUMO

The present study reports the cancer chemopreventive activities of phenyl polyyne diols derived from polyacetylene triol. Thirty-seven analogues based on a 1-phenylhexa-2,4-diyne-1,6-diol scaffold were prepared and their effects on QR activity were elucidated, as well as their cytotoxicities. We found that most of the derivatives based on phenylhexa-2,4-diyne-1,6-diol exhibited good QR induction activity and relatively low cytotoxicity and systemic structure-activity relationship was revealed. In particular, 4-fluorophenyl, 3-chlorophenyl, and 3,4-dioxolophenyl derivatives showed the best profiles in terms of QR induction, cytotoxicity, and CI.


Assuntos
Anticarcinógenos/química , Anticarcinógenos/farmacologia , Poli-Inos/química , Poli-Inos/farmacologia , Relação Estrutura-Atividade
10.
Nanotechnology ; 27(42): 425401, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27632684

RESUMO

In this work, we demonstrate homogeneously distributed In0.3Ga0.7N/GaN quantum disks (QDs), with an average diameter below 10 nm and a high density of 2.1 × 10(11) cm(-2), embedded in 20 nm tall nanopillars. The scalable top-down fabrication process involves the use of self-assembled ferritin bio-templates as the etch mask, spin coated on top of a strained In0.3Ga0.7N/GaN single quantum well (SQW) structure, followed by a neutral beam etch (NBE) method. The small dimensions of the iron cores inside ferritin and nearly damage-free process enabled by the NBE jointly contribute to the observation of photoluminescence (PL) from strain-relaxed In0.3Ga0.7N/GaN QDs at 6 K. The large blueshift of the peak wavelength by over 70 nm manifests a strong reduction of the quantum-confined Stark effect (QCSE) within the QD structure, which also agrees well with the theoretical prediction using a 3D Schrödinger equation solver. The current results hence pave the way towards the realization of large-scale III-N quantum structures using the combination of bio-templates and NBE, which is vital for the development of next-generation lighting and communication devices.

11.
Bioorg Med Chem Lett ; 25(18): 4020-3, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26253633

RESUMO

An increasing importance of chemoprevention for controlling cancer risks prompted the discovery of new active cancer chemopreventive agents. In this study, we designed and synthesized substituted hexa-2,4-diyne-1,6-diols, more structurally simplified, tunable, and easily preparable than natural gymnasterkoreaynes, and evaluated their cancer chemopreventive activities by measuring concentration of doubling quinone reductase activity (CD), cell viability, and chemopreventive index (CI). Most of the diols exhibited good CD activity and low cytotoxicity. In particular, tetradeca-5,7-diyne-4,9-diol and 2-methyltetradeca-5,7-diyne-4,9-diol showed the best cancer chemopreventive activity, approximately equipotent to that of sulforaphane. And, by synthesizing optically active stereoisomers of selected active compounds, the effect of stereochemistry was also studied. Eventually, we produced a chemopreventive compound for in vivo study.


Assuntos
Acetileno/farmacologia , Anticarcinógenos/farmacologia , Neoplasias/prevenção & controle , Acetileno/síntese química , Acetileno/química , Anticarcinógenos/síntese química , Anticarcinógenos/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Células Hep G2 , Humanos , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Relação Estrutura-Atividade
12.
Crit Rev Food Sci Nutr ; 54(11): 1458-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24580540

RESUMO

Recent reports on cocoa are appealing in that a food commonly consumed for pure pleasure might also bring tangible benefits for human health. Cocoa consumption is correlated with reduced health risks of cardiovascular diseases, hypertension, atherosclerosis, and cancer, and the health-promoting effects of cocoa are mediated by cocoa-driven phytochemicals. Cocoa is rich in procyanidins, theobromine, (-)-epicatechin, catechins, and caffeine. Among the phytochemicals present in consumed cocoa, theobromine is most available in human plasma, followed by caffeine, (-)-epicatechin, catechin, and procyanidins. It has been reported that cocoa phytochemicals specifically modulate or interact with specific molecular targets linked to the pathogenesis of chronic human diseases, including cardiovascular diseases, cancer, neurodegenerative diseases, obesity, diabetes, and skin aging. This review summarizes comprehensive recent findings on the beneficial actions of cocoa-driven phytochemicals in molecular mechanisms of human health.


Assuntos
Cacau/química , Promoção da Saúde , Compostos Fitoquímicos/análise , Animais , Disponibilidade Biológica , Cafeína/análise , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus/prevenção & controle , Flavonoides/análise , Flavonoides/química , Flavonoides/farmacocinética , Humanos , Neoplasias/prevenção & controle , Doenças Neurodegenerativas/prevenção & controle , Obesidade/prevenção & controle , Proantocianidinas , Envelhecimento da Pele/efeitos dos fármacos , Teobromina/análise , Teobromina/farmacocinética
13.
Front Genet ; 15: 1401470, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39050246

RESUMO

As genomic selection emerges as a promising breeding method for both plants and animals, numerous methods have been introduced and applied to various real and simulated data sets. Research suggests that no single method is universally better than others; rather, performance is highly dependent on the characteristics of the data and the nature of the prediction task. This implies that each method has its strengths and weaknesses. In this study, we exploit this notion and propose a different approach. Rather than comparing multiple methods to determine the best one for a particular study, we advocate combining multiple methods to achieve better performance than each method in isolation. In pursuit of this goal, we introduce and develop a computational method of the stacked generalization within ensemble methods. In this method, the meta-model merges predictions from multiple base models to achieve improved performance. We applied this method to plant and animal data and compared its performance with currently available methods using standard performance metrics. We found that the proposed method yielded a lower or comparable mean squared error in predicting phenotypes compared to the current methods. In addition, the proposed method showed greater resistance to overfitting compared to the current methods. Further analysis included statistical hypothesis testing, which showed that the proposed method outperformed or matched the current methods. In summary, the proposed stacked generalization integrates currently available methods to achieve stable and better performance. In this context, our study provides general recommendations for effective practices in genomic selection.

14.
Antioxidants (Basel) ; 13(2)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38397832

RESUMO

Gamma-tocopherol methyltransferase (γ-TMT), a key gene in the vitamin E biosynthesis pathway, significantly influences the accumulation of tocochromanols, thereby determining rice nutritional quality. In our study, we analyzed the γ-TMT gene in 475 Korean rice accessions, uncovering 177 genetic variants, including 138 SNPs and 39 InDels. Notably, two functional SNPs, tmt-E2-28,895,665-G/A and tmt-E4-28,896,689-A/G, were identified, causing substitutions from valine to isoleucine and arginine to glycine, respectively, across 93 accessions. A positive Tajima's D value in the indica group suggests a signature of balancing selection. Haplotype analysis revealed 27 haplotypes, with two shared between cultivated and wild accessions, seven specific to cultivated accessions, and 18 unique to wild types. Further, profiling of vitamin E isomers in 240 accessions and their association with haplotypes revealed that Hap_2, distinguished by an SNP in the 3' UTR (tmt-3UTR-28,897,360-T/A) exhibited significantly lower α-tocopherol (AT), α-tocotrienol (AT3), total tocopherol, and total tocotrienol, but higher γ-tocopherol (GT) in the japonica group. Additionally, in the indica group, Hap_2 showed significantly higher AT, AT3, and total tocopherol, along with lower GT and γ-tocotrienol, compared to Hap_19, Hap_20, and Hap_21. Overall, this study highlights the genetic landscape of γ-TMT and provides a valuable genetic resource for haplotype-based breeding programs aimed at enhancing nutritional profiles.

15.
Front Plant Sci ; 14: 1225445, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560030

RESUMO

Early season flooding is a major constraint in direct-seeded rice, as rice genotypes vary in their coleoptile length during anoxia. Trehalose-6-phosphate phosphatase 7 (OsTPP7, Os09g0369400) has been identified as the genetic determinant for anaerobic germination (AG) and coleoptile elongation during flooding. We evaluated the coleoptile length of a diverse rice panel under normal and flooded conditions and investigated the Korean rice collection of 475 accessions to understand its genetic variation, population genetics, evolutionary relationships, and haplotypes in the OsTPP7 gene. Most accessions displayed enhanced flooded coleoptile lengths, with the temperate japonica ecotype exhibiting the highest average values for normal and flooded conditions. Positive Tajima's D values in indica, admixture, and tropical japonica ecotypes suggested balancing selection or population expansion. Haplotype analysis revealed 18 haplotypes, with three in cultivated accessions, 13 in the wild type, and two in both. Hap_1 was found mostly in japonica, while Hap-2 and Hap_3 were more prevalent in indica accessions. Further phenotypic performance of major haplotypes showed significant differences in flooded coleoptile length, flooding tolerance index, and shoot length between Hap_1 and Hap_2/3. These findings could be valuable for future selective rice breeding and the development of efficient haplotype-based breeding strategies for improving flood tolerance.

16.
J Acoust Soc Am ; 130(2): 826-34, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21877798

RESUMO

A multi-scale homogenization technique and a finite element-based solution procedure are employed to compute acoustic absorption in smooth and rough packed microtubes. The absorption considered arises from thermo-viscous interactions between the fluid media and the microtube walls. The homogenization technique requires geometric periodicity, which for smooth tubes is invoked using the periodicity of the finite element mesh; for rough microtubes, the periodicity invoked is that associated with the roughness. Analysis of the packed configurations, for the specific microtube radii considered, demonstrates that surface roughness does not appreciably increase the overall absorption, but instead shifts the peaks and values of the absorption curve. Additionally, the effect of the fluid media temperature on acoustic absorption is also explored. The results of the investigation are used to make conclusions about tailored design of acoustically absorbing microtube-based materials.


Assuntos
Acústica/instrumentação , Simulação por Computador , Materiais de Construção , Arquitetura de Instituições de Saúde/instrumentação , Modelos Teóricos , Ruído/prevenção & controle , Análise Numérica Assistida por Computador , Absorção , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Elementos Finitos , Pressão , Propriedades de Superfície , Temperatura
17.
Chem Biol Drug Des ; 98(5): 733-750, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34310065

RESUMO

Type 2 diabetes is characterized by chronic hyperglycemia. Insulin, a hormone secreted from pancreatic ß-cells, decreases blood glucose levels, and glucagon, a hormone secreted from pancreatic α-cells, increases blood glucose levels by counterregulation of insulin through stimulation of hepatic glucose production. In diabetic patients, dysregulation of glucagon secretion contributes to hyperglycemia. Thus, inhibition of the glucagon receptor is one strategy for the treatment of hyperglycemia in type 2 diabetes. In this paper, we report a series of biphenylsulfonamide derivatives that were designed, synthesized, and then evaluated by cAMP and hepatic glucose production assays as glucagon receptor antagonists. Of these, compound 7aB-3 decreased glucagon-induced cAMP production and glucagon-induced glucose production in the in vitro assays. Glucagon challenge tests and glucose tolerance tests showed that compound 7aB-3 significantly inhibited glucagon-induced glucose increases and improved glucose tolerance. These results suggest that compound 7aB-3 has therapeutic potential for the treatment of type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/síntese química , Receptores de Glucagon/antagonistas & inibidores , Sulfonamidas/síntese química , Animais , Diabetes Mellitus Experimental , Glucagon/metabolismo , Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonamidas/farmacologia
18.
Br J Nutr ; 104(7): 957-64, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20550744

RESUMO

Cocoa polyphenols have antioxidant and anti-inflammatory effects. TNF-α is a pro-inflammatory cytokine that has a vital role in the pathogenesis of inflammatory diseases such as cancer and psoriasis. Vascular endothelial growth factor (VEGF) expression is associated with tumorigenesis, CVD, rheumatoid arthritis and psoriasis. We tested whether cocoa polyphenol extract (CPE) inhibited TNF-α-induced VEGF expression in promotion-sensitive JB6 mouse epidermal cells. CPE significantly inhibited TNF-α-induced up-regulation of VEGF via reducing TNF-α-induced activation of the nuclear transcription factors activator protein-1 (AP-1) and NF-κB, which are key regulators of VEGF expression. CPE also inhibited TNF-α-induced phosphorylation of protein kinase B (Akt) and extracellular signal-regulated kinase. CPE blocked activation of their downstream kinases, p70 kDa ribosomal protein S6 kinase and p90 kDa ribosomal protein S6 kinase. CPE suppressed phosphoinositide 3-kinase (PI3K) activity via binding PI3K directly. CPE did not affect TNF-α-induced phosphorylation of mitogen-activated protein kinase kinase-1 (MEK1) but suppressed TNF-α-induced MEK1 activity. Collectively, these results indicate that CPE reduced TNF-α-induced up-regulation of VEGF by directly inhibiting PI3K and MEK1 activities, which may contribute to its chemopreventive potential.


Assuntos
Antioxidantes/farmacologia , Cacau/química , Epiderme/efeitos dos fármacos , Flavonoides/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Linhagem Celular , Células Epidérmicas , Epiderme/enzimologia , MAP Quinase Quinase 1/antagonistas & inibidores , Camundongos , Inibidores de Fosfoinositídeo-3 Quinase , Extratos Vegetais/química , Polifenóis , Sementes
19.
Br J Nutr ; 104(2): 164-70, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20302682

RESUMO

We evaluated the effects of the two main kiwifruit cultivars (gold kiwifruit (GOK) and green kiwifruit (GRK)) and their active phenolic compound, quercetin, on H2O2-induced inhibition of gap-junction intercellular communication (GJIC) in WB-F344 rat liver epithelial cells. We found that both GOK and GRK protect WB-F344 cells from H2O2-induced inhibition of GJIC. The extracellular signal-regulated protein kinase 1/2 (ERK1/2)-connexin 43 (Cx43) signalling pathway is crucial for the regulation of GJIC, and both GOK and GRK blocked the H2O2-induced phosphorylation of Cx43 and ERK1/2 in WB-F344 cells. Quercetin alone attenuated the H2O2-mediated ERK1/2-Cx43 signalling pathway and consequently reversed H2O2-mediated inhibition of GJIC in WB-F344 cells. A free radical-scavenging assay using 1,1-diphenyl-2-picrylhydrazyl showed that the scavenging activity of quercetin was higher than that of a synthetic antioxidant, butylated hydroxytoluene, per mol, suggesting that the chemopreventive effect of quercetin on H2O2-mediated inhibition of ERK1/2-Cx43 signalling and GJIC may be mediated through its free radical-scavenging activity. Since the carcinogenicity of reactive oxygen species such as H2O2 is attributable to the inhibition of GJIC, GOK, GRK and quercetin may have chemopreventive potential by preventing the inhibition of GJIC.


Assuntos
Actinidia/química , Comunicação Celular/efeitos dos fármacos , Frutas/química , Junções Comunicantes/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Quercetina/farmacologia , Actinidia/classificação , Animais , Linhagem Celular , Conexina 43/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fígado/citologia , Fosforilação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Quercetina/química , Ratos
20.
Comput Biol Chem ; 87: 107278, 2020 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-32563074

RESUMO

Motivated by the characteristics of highly clustered single nucleotide polymorphism (SNP) across the human genome, we propose a set of chromosome-wise fractal dimensions as a measure for identifying an individual for human polymorphism. The fractal dimension quantifies the degree of clustered distribution of SNPs and represents parsimoniously the genetic variation in a chromosome. In this sense, the proposed scheme projects the SNP genotype data into a new space which is simpler and lower in dimension. As an illustrative example, we estimate the chromosome-wise fractal dimensions of SNPs that are extracted from the HapMap of Phase III data set. To determine the validity of the proposed measure, we apply principal component analysis (PCA) to the set of estimated fractal dimensions and demonstrate that the set more or less described the population structure of 11 global populations. We also use multidimensional scaling to relate the genetic distances based on PCA to the geographical distances between global populations. This shows that, similar to the SNP genotype data, the fractal dimensions also has a role in genetic distance in the population structure. In addition, we apply the proposed measure to a signature for the classification of global populations by developing a support vector machine model. The selected feature model predicts the global population with a balanced accuracy of about 77%. These results support that the fractal dimension is an efficient way to describe the genetic variation of global populations.

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