RESUMO
Astringency influences the sensory characteristics and flavor quality of table grapes. We tested the astringency sensory attributes of berries and investigated the concentration of flavan-3-ols/proanthocyanidins (PAs) in skins after the application of the plant growth regulators CPPU and GA3 to the flowers and young berries of the "Summer Black" grape. Our results showed that CPPU and GA3 applications increase sensory astringency perception scores and flavan-3-ol/proanthocyanidin concentrations. Using integrated transcriptomic and proteomic analysis, differentially expressed transcripts and proteins associated with growth regulator treatment were identified, including those for flavonoid biosynthesis that contribute to the changes in sensory astringency levels. Transient overexpression of candidate astringency-related regulatory genes in grape leaves revealed that VvWRKY71, in combination with VvMYBPA1 and VvMYC1, could promote the biosynthesis of proanthocyanidins, while overexpression of VvNAC83 reduced the accumulation of proanthocyanidins. However, in transient promoter studies in Nicotiana benthamiana, VvWRKY71 repressed the promoter of VvMYBPA2, while VvNAC83 had no significant effect on the promoter activity of four PA-related genes, and VvMYBPA1 was shown to activate its own promoter. This study provides new insights into the molecular mechanisms of sensory astringency formation induced by plant growth regulators in grape berries.
Assuntos
Polietilenoglicóis , Poliuretanos , Proantocianidinas , Vitis , Proantocianidinas/metabolismo , Vitis/metabolismo , Frutas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Adstringentes/metabolismo , Proteômica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Genes Reguladores , Regulação da Expressão Gênica de PlantasRESUMO
BACKGROUND: Telomeres inhibit DNA damage response at the ends of the chromosome to suppress cell cycle arrest as well as ensure genome stability. Dyskeratosis congenita (DC), a telomere-related disease, includes the classical triad involving oral leukoplakia, dysplastic nails, and lacy reticular pigment in the neck and/or upper chest. Hoyeraal-Hreidarrson syndrome (HHS), a severe manifestation of DC, frequently occurs during childhood, and patients with HHS often show short-term survival and thus do not exhibit all mucocutaneous manifestations or syndromic features. CASE: We report here a patient with HHS characterized by the proband`s clinical attributes, such as growth delay, bone marrow failure, microcephaly, defects in body development, and the absence of cerebellar hypoplasia combined with Blake`s pouch cyst. By using exome sequencing, novel compound heterozygous mutations (c.1451C > T and c.1266+3del78bp) were detected in the RTEL1 (regulator of telomere elongation helicase 1) gene. CONCLUSIONS: The DNA helicase RTEL1 plays a role in genome stability, DNA replication, telomere maintenance, and genome repair. Terminal restriction fragment length analysis revealed a significantly shorter telomere length of the proband. Our findings provided evidence that compound heterozygous RTEL1 mutations cause HHS.
Assuntos
Bolsas Cólicas , Disceratose Congênita , Deficiência Intelectual , Microcefalia , Humanos , DNA Helicases/genética , Disceratose Congênita/genética , Disceratose Congênita/metabolismo , Retardo do Crescimento Fetal , Instabilidade Genômica , Deficiência Intelectual/genética , Microcefalia/genética , Microcefalia/metabolismo , Mutação , Telômero/metabolismoRESUMO
A series of Fe/ZSM-5 catalysts with different Fe contents were prepared by impregnation method. The catalysts were characterized by TEM, XRD, H2 temperature-programed reduction (H2-TPR), temperature-programed desorption of ammonia (NH3-TPD), and in situ diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS), and the catalytic activity test was also carried out on selective catalytic reduction (SCR) denitration device. Results showed that the single metal iron-supported ZSM-5 catalyst has high deNOx activity in the medium-high temperature range, and the optimal loading of Fe active component is 10 wt%; the deNOx efficiency over 80% at the range of 350-450 °C and 431 °C reaches the maximum of 96.91%. Iron species can be finely dispersed on the surface of the carrier as amorphous oxides, and the crystalline structure of zeolite is retained. The significant redox performance, highly dispersed nanoparticles, and rich Lewis acid sites on the surface of catalyst are favorable for the SCR denitration reaction. Fe/ZSM-5 10 wt% catalyst has rich Lewis acid sites and less B acid sites and Lewis acidic sites play an important role during the reaction. Only Eley-Rideal (E-R) mechanism existed during the NH3-SCR reaction process, and there is no denitration reaction being accomplished by L-H mechanism at 150 °C.
Assuntos
Amônia/química , Ferro/química , Óxidos de Nitrogênio/química , Poluentes Atmosféricos/química , Poluição do Ar/prevenção & controle , Catálise , Ácidos de Lewis/química , Microscopia Eletrônica de Transmissão , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios XRESUMO
INTRODUCTION: Nanomedicine has shown a great potential in perinatal medicine because of its characteristics of sustained, controlled release and targeting ability; on the other hand, it may also lead to unexpected toxicities such as embryotoxicity and even malformation after crossing the placental barrier, but data concerning transplacental transport are scarce. Pullulan acetate (PA) nanoparticles (NPs) are a promising nanocarrier derived from natural polysaccharide; however, their transplacental transport ability and mechanism are unknown. MATERIALS AND METHODS: In this study, fluorescein isothiocyanate (FITC) conjugated PA (PA-FITC) was synthesized. PA-FITC NPs were characterized by dynamic light scattering, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The cytotoxicity of PA-FITC NPs at concentrations of 15, 30, 60, 125, 250, 500, 1,000 and 2,000 µg/mL was studied by cell counting kit-8. The human chorionic gonadotrophin (HCG) cytokine assay was conducted to evaluate the biological function of BeWo b30 cells. Endocytic mechanisms of PA-FITC NPs were investigated via fluorescence analysis. The monolayer properties were characterized by TEM, tight junction staining, transepithelial electrical resistance and fluorescein sodium transportation. The transport ability was measured in the cell based transwell model by confocal imaging and SEM. RESULTS: PA-FITC NPs were almost spherical shape with a size range of 200-300 nm. Cell viability of BeWo b30 cells was up to 100% in all groups. The concentrations of HCG increased with increasing numbers of cells and culture time, which showed the good biological function of BeWo b30 cells. PA-FITC NPs were rapidly endocytosed through caveolae-mediated endocytosis and pinocytosis, with uptake inhibition rates with nystatin (NY) and colchicines (Col) of 55% and 51% respectively. BeWo b30 cell monolayer was formed over 5 days. PA-FITC NPs were found in the cytoplasm of cells on the transwell membranes; while some NPs were found in the basolateral (fetal) compartment over 24 h. CONCLUSION: In summary, PA-FITC NPs are nontoxic, can cross the blood-placental barrier, and show mainly internalization to BeWo b30 cells through caveolae-mediated endocytosis and pinocytosis pathways, major via the former pathway. The results could benefit the adjustment and control of the transplacental transport of nanomedicines.
Assuntos
Endocitose , Glucanos/metabolismo , Modelos Biológicos , Nanopartículas/metabolismo , Placenta/metabolismo , Transporte Biológico , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Gonadotropina Coriônica , Feminino , Feto , Fluoresceína/metabolismo , Fluoresceína-5-Isotiocianato/síntese química , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , GravidezRESUMO
Highly efficient catalytic asymmetric Claisen rearrangements of O-propargyl ß-ketoesters and O-allyl ß-ketoesters have been accomplished under mild reaction conditions. In the presence of the chiral N,N'-dioxide/Ni(II) complex, a wide range of allenyl/allyl-substituted all-carbon quaternary ß-ketoesters was obtained in generally good yield (up to 99%) and high diastereoselectivity (up to 99:1 d.r.) with excellent enantioselectivity (up to 99% ee).
RESUMO
Targeting LRH-1: Virtual screening and molecular modeling were used to identify novel antagonists of liver receptor homolog-1 (LRH-1), an emerging therapeutic target for breast cancer. Hit compounds were synthesized and biologically assayed, and the preliminary results suggest that raloxifene-based analogues, substituted at the position C-7 of the benzothiophene ring, might generate an inactive protein conformation through binding and thus antagonize this nuclear receptor.
Assuntos
Cloridrato de Raloxifeno/análogos & derivados , Cloridrato de Raloxifeno/farmacologia , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Células COS , Chlorocebus aethiops , Desenho de Fármacos , Feminino , Humanos , Ligantes , Modelos Moleculares , Conformação Proteica/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/metabolismoRESUMO
A series of compounds designed to adopt a conformation similar to the tubulin-binding T-Taxol conformation of the anticancer drug paclitaxel has been synthesized. Both the internally bridged analogs 37-39, 41 and the open-chain analogs 27-29 and 43 were prepared. The bridged analogs 37-39 and 41 were synthesized by Grubbs' metatheses of compounds 30-32 and 33, which, in turn, were prepared by coupling ß-lactams 24-26 with alcohols 22 and 23. Both the bridged and the open-chain analogs showed moderate to good cytotoxicity.
Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Paclitaxel/análogos & derivados , Paclitaxel/farmacologia , Antineoplásicos Fitogênicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Modelos Moleculares , Conformação Molecular , Neoplasias/tratamento farmacológico , Paclitaxel/síntese química , Paclitaxel/química , Tubulina (Proteína)/metabolismoRESUMO
A series of novel curcumin analogs, symmetrical dienones, were previously shown to possess cytotoxic, anti-angiogenic and anti-tumor activities. Analogs 1 (EF24) and 2 (EF31) share the dienone scaffold and serve as Michael acceptors. We propose that the anti-cancer effects of 1 and 2 are mediated in part by redox-mediated induction of apoptosis. In order to support this concept, 1 and 2 were treated with L-glutathione (GSH) and cysteine-containing dipeptides under mild conditions to form colorless water-soluble adducts, which were identified by LC/MS. Comparison of the cytotoxic action of 1, 2 and the corresponding conjugates, 1-(GSH)(2) and 2-(GSH)(2), illustrated that the two classes of compounds exhibit essentially identical cell killing capabilities. Compared with the yellow, somewhat light sensitive and nearly water insoluble compounds 1 and 2, the glutathione conjugates represent a promising new series of stable and soluble anti-tumor pro-drugs.