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1.
Plant Cell ; 36(6): 2289-2309, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38466226

RESUMO

Flowering plant genomes encode four or five DICER-LIKE (DCL) enzymes that produce small interfering RNAs (siRNAs) and microRNAs, which function in RNA interference (RNAi). Different RNAi pathways in plants effect transposon silencing, antiviral defense, and endogenous gene regulation. DCL2 acts genetically redundantly with DCL4 to confer basal antiviral defense. However, DCL2 may also counteract DCL4 since knockout of DCL4 causes growth defects that are suppressed by DCL2 inactivation. Current models maintain that RNAi via DCL2-dependent siRNAs is the biochemical basis of both effects. Here, we report that DCL2-mediated antiviral resistance and growth defects cannot be explained by the silencing effects of DCL2-dependent siRNAs. Both functions are defective in genetic backgrounds that maintain high levels of DCL2-dependent siRNAs, either with specific point mutations in DCL2 or with reduced DCL2 dosage because of heterozygosity for dcl2 knockout alleles. Intriguingly, all DCL2 functions require its catalytic activity, and the penetrance of DCL2-dependent growth phenotypes in dcl4 mutants correlates with DCL2 protein levels but not with levels of major DCL2-dependent siRNAs. We discuss this requirement and correlation with catalytic activity but not with resulting siRNAs, in light of other findings that reveal a DCL2 function in innate immunity activation triggered by cytoplasmic double-stranded RNA.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Interferência de RNA , Ribonuclease III , Arabidopsis/genética , Arabidopsis/virologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Mutação , Doenças das Plantas/virologia , Doenças das Plantas/imunologia , Doenças das Plantas/genética , Ribonuclease III/genética , Ribonuclease III/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
2.
Chemphyschem ; : e202400075, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822681

RESUMO

Environmental pollution management and renewable energy development are humanity's biggest issues in the 21st century. The rise in atmospheric CO2, which has surpassed 400 parts per million, has stimulated research on CO2 reduction and conversion methods. Presently, photocatalytic conversion of CO2 to valuable hydrocarbons enables the transformation of solar energy into chemical energy and offers a novel avenue for energy conversion while regulating the greenhouse effect. This is an ideal strategy for simultaneously addressing environmental issues and the energy crisis. Photocatalysts are essential to photocatalytic processes. Photocatalyst is the core of photocatalytic technology, and graphite carbon nitride (g-C3N4) has attracted much attention because of its nonmetallic characteristics, and it has the characteristics of low cost, tunable electronic structure, easy manufacture and strong reducibility. However, its activity is not only affected by external reaction conditions, but also by the band gap structure, physical and chemical stability, surface morphology and specific surface area of the photocatalyst it. In this paper, the application progress of g-C3N4-based photocatalytic materials in CO2 reduction is reviewed, and the modification strategies of g-C3N4-based catalysts to obtain better catalytic efficiency and selectivity in CO2 photocatalytic reduction are summarized, and the future development of this material is prospected.

3.
BMC Med ; 21(1): 330, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37649020

RESUMO

BACKGROUND: Natural killer/T cell lymphoma (NKTCL) is an aggressive lymphoma with a poor prognosis. Chimeric antigen receptor-transduced T (CAR-T) cell therapy has become a promising immunotherapeutic strategy against haematologic malignancies. METHODS: In this study, four CAR-T cell lines (CD38-CAR, LMP1-CAR, CD38-LMP1 tandem CAR 1 and CD38-LMP1 tandem CAR 2) were generated. The effect of CAR-T cells against NKTCL cells was evaluated both in vitro and in vivo. Expression of T cell activation markers and cytokines produced by CAR-T cells were detected by flow cytometry. RESULTS: The four CAR-T cell lines could effectively eliminate malignant NKTCL cells. They could be activated and produce inflammatory cytokines in a target-dependent manner. In vivo tests showed that the CAR-T cells exhibited significant antitumour effects in a xenotransplanted NKTCL mouse model. CONCLUSIONS: In summary, four CAR-T cell lines exhibited significant cytotoxicity against NKTCL cells both in vitro and in vivo. These results indicated the effective therapeutic promise of CD38 and LMP1 CAR-T cells in NKTCL.


Assuntos
Linfoma de Células T , Receptores de Antígenos Quiméricos , Animais , Camundongos , Receptores de Antígenos Quiméricos/genética , Citocinas , Modelos Animais de Doenças , Linfócitos T
4.
J Asian Nat Prod Res ; 25(6): 571-580, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36125926

RESUMO

A series of 4-(propargyloxy) benzenesulfonamide derivatives with different substituents on the benzene ring were synthesized and evaluated for their insecticidal activity. Some of the compounds showed good insecticidal activity against Mythimna separata, and the LC50 value of the most active compound B2.5 was 0.235 mg/ml. Ultrastructural changes in the midgut epithelial cells of Mythimna separata were observed using transmission electron microscopy, and severe structural damage was found in microvilli, mitochondria and rough endoplasmic reticulum. It indicates that the possible site of action of these benzenesulfonamides is the cytoplasmic membrane and endomembrane system of the midgut epithelial cells. The above provides a basis for the development of novel insecticidal active compounds with a novel mechanism of action.


Assuntos
Inseticidas , Mariposas , Animais , Larva , Inseticidas/farmacologia , Mariposas/ultraestrutura , Estrutura Molecular , Benzenossulfonamidas
5.
J Asian Nat Prod Res ; 24(4): 361-370, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34042537

RESUMO

In our previous studies, a kind of novel benzenesulfonamides was found to be a candidate insecticidal compounds. It was shown that propargyloxy and sulfonamide groups are pharmacodynamic groups. One hundred and twenty-six (126) naphthalenesulfonamides derivatives with propargyloxy functionality were designed and synthesized, and their insecticidal activities were determined. Some of them showed outstanding activity, with LC50 values as low as 0.202 mg ml-1, much lower than that of the positive control celangulin V (23.9 mg ml-1). In addition, the structure-activity relationships were discussed, and molecular docking was used to verify the binding mode of the compound and the target receptor.


Assuntos
Inseticidas , Desenho de Fármacos , Inseticidas/farmacologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Naftalenos/farmacologia , Relação Estrutura-Atividade , Sulfonamidas/farmacologia
6.
Molecules ; 28(1)2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36615360

RESUMO

There are limited reports about the effect of different heat treatments on the quality and flavor of Black Tibetan sheep meat. The current study examined the effect of pan-frying, deep-frying, baking, and boiling treatment on the quality of Black Tibetan sheep meat; the amino acid, fatty acid, and volatile flavor compounds (VFCs) were investigated by a texture analyzer, ultra-high-performance liquid chromatography (UHPLC), gas chromatography (GC), and headspace-gas chromatography-ion mobility (HS-GC-IMS). The key VFCs were identified through orthogonal partial least squares discrimination analysis (OPLS-DA), and variable importance projection (VIP) values. In addition, Pearson's correlations between meat quality parameters and key VFCs were examined. The sensory scores, including texture, color, and appearance, of baked and pan-fried meat were higher than those of deep-fried and boiled meat. The protein (40.47%) and amino acid (62.93 µmol/g) contents were the highest in pan-fried meat (p < 0.05). Additionally, it contained the highest amounts of monounsaturated and polyunsaturated fatty acids, such as oleic, linoleic, and α-linolenic acids (p < 0.05). Meanwhile, pan-fried and deep-fried meat had higher amounts of VFCs than baked meat. The OPLS-DA similarity and fingerprinting analyses revealed significant differences between the three heat treatment methods. Aldehydes were the key aroma compounds in pan-fried meat. Importantly, 3-methylbutyraldehyde and 2-heptanone contents were positively correlated with eicosenoic, oleic, isooleic, linoleic, α-Linolenic, and eicosadiene acids (p < 0.05). To sum up, pan-fried Black Tibetan sheep meat had the best edible, nutritional, and flavor quality.


Assuntos
Temperatura Alta , Compostos Orgânicos Voláteis , Animais , Ovinos , Tibet , Cromatografia Gasosa , Análise Multivariada , Carne/análise , Aminoácidos , Compostos Orgânicos Voláteis/análise
7.
Zhongguo Zhong Yao Za Zhi ; 47(19): 5246-5255, 2022 Oct.
Artigo em Zh | MEDLINE | ID: mdl-36472031

RESUMO

The present study quickly identified the ginsenosides in fresh Panax ginseng and specified the effects of different drying methods(50 ℃-drying, 80 ℃-drying, and-70 ℃ freeze-drying) on ginsenosides.Three P.ginseng products by different drying methods were prepared, and the UHPLC-Q-Exactive Orbitrap high-resolution liquid mass spectrometry(MS) technique was applied to perform gradient elution using water-acetonitrile as the mobile phase, and the data collected in the negative ion mode were analyzed using X Calibur 2.2.The results showed that 57 saponins were identified from fresh P.ginseng.As revealed by the comparison with the fresh P.ginseng, in terms of the loss of ginsenosides, the dried products were ranked as the dried product at 50 ℃, freeze-dried products at-70 ℃, and the dried product at 80 ℃ in the ascending order.This study elucidated the effects of different drying methods on the types and relative content of ginsenosides, which can provide references for the processing of P.ginseng in the producing areas.


Assuntos
Ginsenosídeos , Panax , Saponinas , Ginsenosídeos/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos
8.
Circ Res ; 122(5): 730-741, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29301853

RESUMO

RATIONALE: An elevated level of plasma LDL (low-density lipoprotein) is an established risk factor for cardiovascular disease. Recently, we reported that the (pro)renin receptor ([P]RR) regulates LDL metabolism in vitro via the LDLR (LDL receptor) and SORT1 (sortilin-1), independently of the renin-angiotensin system. OBJECTIVES: To investigate the physiological role of (P)RR in lipid metabolism in vivo. METHODS AND RESULTS: We used N-acetylgalactosamine modified antisense oligonucleotides to specifically inhibit hepatic (P)RR expression in C57BL/6 mice and studied the consequences this has on lipid metabolism. In line with our earlier report, hepatic (P)RR silencing increased plasma LDL-C (LDL cholesterol). Unexpectedly, this also resulted in markedly reduced plasma triglycerides in a SORT1-independent manner in C57BL/6 mice fed a normal- or high-fat diet. In LDLR-deficient mice, hepatic (P)RR inhibition reduced both plasma cholesterol and triglycerides, in a diet-independent manner. Mechanistically, we found that (P)RR inhibition decreased protein abundance of ACC (acetyl-CoA carboxylase) and PDH (pyruvate dehydrogenase). This alteration reprograms hepatic metabolism, leading to reduced lipid synthesis and increased fatty acid oxidation. As a result, hepatic (P)RR inhibition attenuated diet-induced obesity and hepatosteatosis. CONCLUSIONS: Collectively, our study suggests that (P)RR plays a key role in energy homeostasis and regulation of plasma lipids by integrating hepatic glucose and lipid metabolism.


Assuntos
Fígado Gorduroso/metabolismo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Obesidade/metabolismo , Receptores de Superfície Celular/metabolismo , Acetil-CoA Carboxilase/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/etiologia , Inativação Gênica , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Complexo Piruvato Desidrogenase/metabolismo , Receptores de Superfície Celular/genética , Receptor de Pró-Renina
9.
Inorg Chem ; 59(10): 7181-7187, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32352295

RESUMO

Lanthanide (such as Tb and Eu) metal-organic frameworks (MOFs) have been widely used in fluorescent probes because of their multiple coordination modes and brilliant fluorescence characteristic. Many lanthanide MOFs were applied in detecting metal ions, inorganic anions, and small molecules. However, it's rarely reported that Ln-MOF was devoted to detecting malachite green (MG) and uric acid (UA). We prepared a europium-based metal-organic framework (Eu-TDA) (TDA = 2,5-thiophenedicarboxylic acid group). Luminescence studies demonstrated that Eu-TDA can rapidly detect MG and UA with excellent selectivity and sensitivity, where individual quenching efficiency Ksv (MG: 5.8 × 105 M-1; UA: 4.15 × 104 M-1) and detection limit (MG: 0.0221 µM; UA: 0.689 µM) were regarded as the excellent MOF sensors for detecting MG and UA. The quenching of Eu-TDA's fluorescence emission by MG and UA was likely due to the spectral overlap, energy transfer, and competition. Among 11 metal cations and 14 anions, Eu-TDA can quickly and effectively recognize MG and UA with highly selective and sensitive properties. Our method possesses potential application in detecting UA in human blood and MG in the fishpond.

10.
Chem Biodivers ; 17(7): e2000187, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32384197

RESUMO

(20S)-Protopanaxadiol ginsenosides Rg3, Rh2 and PPD have been demonstrated for their anticancer activity. However, the underlying mechanism of their antitumor activity remains unclear. In the present study, we investigated the role of these three ginsenosides on cell proliferation and death of human gastric cancer cells (HGC-27 cells). The sulforhodamine B (SRB) assay, Western blot analysis, fluorescence microscopy, confocal microscopy, high performance liquid chromatography (HPLC) analysis, flow cytometry, and transmission electron microscopy (TEM) were used to evaluate cell proliferation, apoptosis, and autophagy. The results showed that both Rh2 and PPD were more effective than Rg3 in inhibiting HGC-27 cell proliferation and inducing cytoplasmic vacuolation, while no significant changes in apoptosis were observed. Interestingly, cytoplasmic vacuolation and blockade of autophagy flux were observed after treatment with Rh2 and PPD. Rh2 obviously up-regulated the expression of the LC3II and p62. Furthermore, the increase in lysosomal pH and membrane rupture was observed in Rh2-treated and PPD-treated cells. When HGC-27 cells were pretreated with bafilomycin A1, a specific inhibitor of endosomal acidification, cellular vacuolization was increased, and the cell viability was significantly decreased, which indicated that Rh2-induced lysosome-damage accelerated cell death. Furthermore, data derived from mitochondrial analysis showed that excessive mitochondrial reactive oxygen species (ROS) and dysregulation of mitochondrial energy metabolism were caused by Rh2 and PPD treatment in HGC-27 cells. Taken together, these phenomena indicated that Rh2 and PPD inhibited HCG-27 cells proliferation by inducing mitochondria damage, dysfunction of lysosomes, and blockade of autophagy flux. The number of glycosyl groups at C-3 position could have an important effect on the cytotoxicity of Rg3, Rh2 and PPD.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Ginsenosídeos/farmacologia , Sapogeninas/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ginsenosídeos/química , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Sapogeninas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Molecules ; 25(8)2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32316267

RESUMO

Characterization of the structure and pharmacological activity of Berberis dasystachya Maxim., a traditional Tibetan medicinal and edible fruit, has not yet been reported. In this study, central composite design (CCD) combined with response surface methodology (RSM) was applied to optimize the extraction conditions of B. dasystachya oil (BDSO) using the supercritical carbon dioxide (SC-CO2) extraction method, and the results were compared with those obtained by the petroleum ether extraction (PEE) method. The chemical characteristics of BDSO were analyzed, and its antioxidant activity and in vitro cellular viability were studied by DPPH, ABTS, reducing power assay, and MTT assay. The results showed that the maximum yield of 12.54 ± 0.56 g/100 g was obtained at the optimal extraction conditions, which were: pressure, 25.00 MPa; temperature 59.03 °C; and CO2 flow rate, 2.25 SL/min. The Gas chromatography (GC) analysis results showed that BDSO extracted by the SC-CO2 method had higher contents of unsaturated fatty acids (85.62%) and polyunsaturated fatty acids (57.90%) than that extracted by the PEE method. The gas chromatography used in conjunction with ion mobility spectrometry (GC-IMS) results showed that the main volatile compounds in BDSO were aldehydes and esters. BDSO also exhibited antioxidant ability in a dose-dependent manner. Moreover, normal and cancer cells incubated with BDSO had survival rates of more than 85%, which indicates that BDSO is not cytotoxic. Based on these results, the BDSO extracted by the SC-CO2 method could potentially be used in other applications, e.g., those that involve using berries of B. dasystachya.


Assuntos
Antioxidantes/análise , Berberis/química , Óleos de Plantas/análise , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cromatografia com Fluido Supercrítico , Óleos de Plantas/farmacologia , Sementes/química
12.
Angew Chem Int Ed Engl ; 59(41): 17966-17973, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32613700

RESUMO

In principle, nanoparticle occlusion within crystals provides a straightforward and efficient route to make new nanocomposite materials. However, developing a deeper understanding of the design rules underpinning this strategy is highly desirable. In particular, controlling the spatial distribution of the guest nanoparticles within the host crystalline matrix remains a formidable challenge. Herein, we show that the surface chemistry of the guest nanoparticles and the [Ca2+ ] concentration play critical roles in determining the precise spatial location of the nanoparticles within calcite crystals. Moreover, in situ studies provide important mechanistic insights regarding surface-confined nanoparticle occlusion. Overall, this study not only provides useful guidelines for efficient nanoparticle occlusion, but also enables the rational design of patterned calcite crystals using model anionic block copolymer vesicles.

13.
J Am Chem Soc ; 141(6): 2557-2567, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30694663

RESUMO

Nanoparticle occlusion within growing crystals is of considerable interest because (i) it can enhance our understanding of biomineralization and (ii) it offers a straightforward route for the preparation of novel nanocomposites. However, robust design rules for efficient occlusion remain elusive. Herein, we report the rational synthesis of a series of silica-loaded poly(glycerol monomethacrylate)-poly(2-hydroxypropyl methacrylate)-poly(ethylene glycol dimethacrylate)-poly(methacrylic acid) tetrablock copolymer vesicles using polymerization-induced self-assembly. The overall vesicle dimensions remain essentially constant for this series; hence systematic variation of the mean degree of polymerization (DP) of the anionic poly(methacrylic acid) steric stabilizer chains provides an unprecedented opportunity to investigate the design rules for efficient nanoparticle occlusion within host inorganic crystals such as calcite. Indeed, the stabilizer DP plays a decisive role in dictating both the extent of occlusion and the calcite crystal morphology: sufficiently long stabilizer chains are required to achieve extents of vesicle occlusion of up to 41 vol %, but overly long stabilizer chains merely lead to significant changes in the crystal morphology, rather than promoting further occlusion. Furthermore, steric stabilizer chains comprising anionic carboxylate groups lead to superior occlusion performance compared to those composed of phosphate, sulfate, or sulfonate groups. Moreover, occluded vesicles are subjected to substantial deformation forces, as shown by the significant change in shape after their occlusion. It is also demonstrated that such vesicles can act as "Trojan horses", enabling the occlusion of non-functional silica nanoparticles within calcite. In summary, this study provides important new physical insights regarding the efficient incorporation of guest nanoparticles within host inorganic crystals.

14.
J Am Chem Soc ; 141(6): 2481-2489, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30698420

RESUMO

Crystallization is widely used by synthetic chemists as a purification technique because it usually involves the expulsion of impurities. In this context, the efficient occlusion of guest nanoparticles within growing host crystals can be regarded as a formidable technical challenge. Indeed, although there are various reports of successful nanoparticle occlusion within inorganic crystals in the literature, robust design rules remain elusive. Herein, we report the synthesis of two pairs of sterically stabilized diblock copolymer nanoparticles with identical compositions but varying particle size, morphology, stabilizer chain length, and stabilizer chain surface density via polymerization-induced self-assembly (PISA). The mean degree of polymerization of the stabilizer chains dictates the spatial distribution of these model anionic nanoparticles within calcite (CaCO3): relatively short stabilizer chains merely result in near-surface occlusion, whereas sufficiently long stabilizer chains are essential to achieve uniform occlusion. This study reconciles the various conflicting literature reports of occluded nanoparticles being either confined to surface layers or uniformly occluded throughout the host matrix and hence provides important new insights regarding the criteria required for efficient nanoparticle occlusion within inorganic crystals.

15.
Appl Microbiol Biotechnol ; 103(14): 5739-5750, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31152202

RESUMO

Auxiliary activity family 9 (AA9) lytic polysaccharide monooxygenases (LPMOs) show significant synergism with cellulase in cellulose degradation. In recent years, there have been many reports on AA9 LPMOs; however, the identification of efficient and thermostable AA9 LPMOs with broad potential for industrial applications remains necessary. In this study, a new AA9 LPMO from Talaromyces cellulolyticus, named TcAA9A, was identified. An analysis of the oxidation products of phosphoric acid-swollen cellulose categorized TcAA9A as a type 3 AA9 LPMO, and TcAA9A exhibited a better synergistic effect with cellulase from Trichoderma reesei than what is seen with TaAA9A, a well-studied AA9 LPMO from Thermoascus aurantiacus. Two AA9 LPMOs were successfully expressed in T. reesei, and the transformants were named TrTcAA9A and TrTaAA9A. The activities and thermostabilities of the AA9 LPMOs in TrTcAA9A were higher than those of the AA9 LPMOs in TrTaAA9A or the parent. The enzyme solution of TrTcAA9A was more efficient than that of the parent or TrTaAA9A for the degradation of Avicel and delignified corncob residue. Thus, TcAA9A showed a better performance than TaAA9A in T. reesei cellulase cocktails. This study may offer an innovative solution for improving enzyme cocktail activity for lignocellulosic degradation.


Assuntos
Proteínas Fúngicas/metabolismo , Lignina/metabolismo , Oxigenases de Função Mista/metabolismo , Polissacarídeos/metabolismo , Thermoascus/enzimologia , Celulase/metabolismo , Celulose/metabolismo , Estabilidade Enzimática , Oxirredução , Temperatura , Trichoderma/metabolismo
16.
Proc Natl Acad Sci U S A ; 113(27): 7584-9, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-27339131

RESUMO

Incipient sympatric speciation in blind mole rat, Spalax galili, in Israel, caused by sharp ecological divergence of abutting chalk-basalt ecologies, has been proposed previously based on mitochondrial and whole-genome nuclear DNA. Here, we present new evidence, including transcriptome, DNA editing, microRNA, and codon usage, substantiating earlier evidence for adaptive divergence in the abutting chalk and basalt populations. Genetic divergence, based on the previous and new evidence, is ongoing despite restricted gene flow between the two populations. The principal component analysis, neighbor-joining tree, and genetic structure analysis of the transcriptome clearly show the clustered divergent two mole rat populations. Gene-expression level analysis indicates that the population transcriptome divergence is displayed not only by soil divergence but also by sex. Gene ontology enrichment of the differentially expressed genes from the two abutting soil populations highlights reproductive isolation. Alternative splicing variation of the two abutting soil populations displays two distinct splicing patterns. L-shaped FST distribution indicates that the two populations have undergone divergence with gene flow. Transcriptome divergent genes highlight neurogenetics and nutrition characterizing the chalk population, and energetics, metabolism, musculature, and sensory perception characterizing the abutting basalt population. Remarkably, microRNAs also display divergence between the two populations. The GC content is significantly higher in chalk than in basalt, and stress-response genes mostly prefer nonoptimal codons. The multiple lines of evidence of ecological-genomic and genetic divergence highlight that natural selection overrules the gene flow between the two abutting populations, substantiating the sharp ecological chalk-basalt divergence driving sympatric speciation.


Assuntos
Especiação Genética , MicroRNAs/metabolismo , Spalax/genética , Simpatria , Transcriptoma , Animais , Carbonato de Cálcio , Ecossistema , Feminino , Fluxo Gênico , Masculino , Silicatos , Solo , Spalax/metabolismo
17.
Small ; 14(17): e1703873, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29611305

RESUMO

Compared to bulk metal-organic framework (MOF), 2D MOF nanosheets have gained intensive research attention due to their ultrathin thickness and large surface area with highly accessible active sites. However, structural deterioration and morphological damage have impeded producing high-quality MOF nanosheets during exfoliation. Here, first a new layered bulk MOF ZSB-1 is synthesized and several solvents such as isopropanol, methanol, n-hexyl alcohol, and N,N-dimethylformamide are surveyed to examine their performance for the exfoliation of layered ZSB-1. As a result, a highly solvent-stable metal-organic framework rectangular nanosheet retaining undamaged morphology is obtained by the soft-physical method in n-hexyl alcohol. Theoretical simulations reveal that the strong interaction energy between n-hexyl alcohol and MOF layers is responsible for the best exfoliation performance of making the bulk MOF into nanosheets. In addition, ZSB-1 shows a tunable fluorescence peak position, fluorescent lifetime, and quantum yield by simply changing the solvent and morphology. Besides, the ZSB-1 was selected as a fluorescence sensor to detect metal ions, and ZSB-1 nanosheet exhibits excellent sensing ability for Fe3+ . It is worth noting that the ZSB-1 nanosheet has better detection limit performance of 0.054 × 10-6 m than that of its bulk counterpart.

18.
Inorg Chem ; 57(9): 5232-5239, 2018 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-29659261

RESUMO

Three Cd(II) iso-frameworks {[Cd(BIPA)(IPA)]·DMF} n (1), {[Cd(BIPA)(HIPA)]·DMF} n (2), and {[Cd(BIPA)(NIPA)]·2H2O} n (3) were synthesized from the self-assembly of the BIPA ligand (BIPA = bis(4-(1 H-imidazol-1-yl)phenyl)amine) and different carboxylic ligands (H2IPA = isophthalic acid, H2HIPA = 5-hydroxyisophthalic acid, H2NIPA = 5-nitroisophthalic acid) with Cd(II), which have amino groups, amino and phenolic hydroxyl groups, and amino and nitro groups, respectively. Both 1 and 2 exhibit CO2 uptakes of more than 20 wt %, indicating that amino and phenolic hydroxyl functionalized groups are beneficial to CO2 adsorption. Their applications and mechanisms in detecting metal ions were researched. The results exhibit that 1 and 2 are dual-responsive photoluminescent sensors for Hg2+ and Pb2+ ions with low detection concentration and high quenching constant. Besides, like most MOFs, 3 can detect a trace quantity of Fe3+ and Cu2+.

19.
Molecules ; 23(12)2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513920

RESUMO

Nanoencapsulation of α-tocopherol (α-TOC) by blending sodium oleate (NaOl) and rebaudioside A (RebA) was successfully prepared by self-assembly method under mild conditions. The optimized nanoemulsion showed the loading capacity of α-TOC was 30 wt% of sodium oleate. FTIR analysis suggested that hydrogen bonds and hydrophobic interactions were the major forces in α-TOC-NaOl/RebA complexes that were spherical and possessed well-distinguishable core-shell structures. The freeze-dried α-TOC-NaOl/RebA complexes had great stability under ambient conditions. The release profile of α-TOC showed a first-order kinetics reaching around 67.9% after 90 h at 25 °C. Nanoencapsulation improved dispersibility and greatly increased the antioxidant activity of α-TOC. Therefore, the stable α-TOC-NaOl/RebA core-shell complexes prepared from "generally recognized as safe" (GRAS) ingredients have great potential to supplement α-TOC in food and cosmetic products.


Assuntos
Antioxidantes/farmacologia , Diterpenos do Tipo Caurano/química , Nanoconchas/química , alfa-Tocoferol/química , alfa-Tocoferol/farmacologia , Antioxidantes/química , Liberação Controlada de Fármacos , Emulsões/química , Aditivos Alimentares/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Liofilização , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Ácido Oleico/química , Espectroscopia de Infravermelho com Transformada de Fourier , alfa-Tocoferol/farmacocinética
20.
Inorg Chem ; 56(5): 2936-2940, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28225602

RESUMO

By employing a rational design approach, we synthesized three luminescent metal-organic frameworks (MOFs) 1-3 affording different coordination modes of V-shaped thienylpyridyl ligand. Their application in detecting metal ions was explored, and the mechanism was inferred. And the result exhibits that MOF 3 is a dual-responsive luminescent probe for Fe3+ and Al3+ ions.

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