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1.
Front Aging Neurosci ; 16: 1377058, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681668

RESUMO

Vitamin D is a lipid soluble steroid hormone, which plays a critical role in the calcium homeostasis, neuronal development, cellular differentiation, and growth by binding to vitamin D receptor (VDR). Associations between VDR gene polymorphism and Alzheimer's disease (AD), Parkinson's disease (PD), and mild cognitive impairment (MCI) risk has been investigated extensively, but the results remain ambiguous. The aim of this study was to comprehensively assess the correlations between four VDR polymorphisms (FokI, BsmI, TaqI, and ApaI) and susceptibility to AD, PD, and MCI. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to determine the relationship of interest. Pooled analyses suggested that the ApaI polymorphism decreased the overall AD risk, and the TaqI increased the overall PD susceptibility. In addition, the BsmI and ApaI polymorphisms were significantly correlated with the overall MCI risk. Stratified analysis by ethnicity further showed that the TaqI and ApaI genotypes reduced the AD predisposition among Caucasians, while the TaqI polymorphism enhanced the PD risk among Asians. Intriguingly, carriers with the BB genotype significantly decreased the MCI risk in Asian descents, and the ApaI variant elevated the predisposition to MCI in Caucasians and Asians. Further studies are need to identify the role of VDR polymorphisms in AD, PD, and MCI susceptibility.

2.
Plant Physiol Biochem ; 208: 108537, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38513517

RESUMO

Pre-harvest spraying of benzothiadiazole (BTH) can improve the winemaking properties of grapes, especially their aroma compounds and phenolics. Limited research has explored the molecular mechanisms by which BTH influences the accumulation of grape aroma precursors during early grape development. This study investigated the effects and putative molecular mechanisms of applying 0.37 mM BTH through whole-plant spraying on the accumulation of aroma metabolism precursors and gene expression in Cabernet Gernischt grapes during ripening. The results showed that BTH treatment increased the levels of fructose, alanine, aspartate, threonine, myristic acid, myristoleic acid, palmitic acid, ß-cryptoxanthin, norisoprenoids and methoxypyrazines. Contrarily, it decreased the levels of glucose, sucrose, phenylalanine, tyrosine, leucine, valine, glycine, arginine, histidine, total unsaturated fatty acids (particularly linoleic acid), zeaxanthin, lutein, and organic acids. Additionally, BTH upregulated the expression of genes associated with the production and degradation of amino acids, fatty acids, and carotenoids while decreasing the expression of genes involved in the synthesis and degradation of soluble sugars and organic acids. Ten different metabolites, including fumaric acid, were identified as potential biological markers for distinguishing BTH-treated grapes from control grapes. The study demonstrates that BTH treatment had a substantial impact on the concentration and developmental patterns of aroma metabolism precursors. Furthermore, it altered the winemaking characteristics of Cabernet Gernischt grapes by modulating genes associated with the production and breakdown of metabolites.


Assuntos
Tiadiazóis , Vitis , Vinho , Vitis/metabolismo , Vinho/análise , Odorantes/análise , Melhoria de Qualidade , Frutas/metabolismo
3.
BMC Plant Biol ; 24(1): 122, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373883

RESUMO

Prohexadione-Calcium (Pro-Ca) plays key roles in improving fruit quality and yield by regulating various aspects of plant growth. However, the effects of how Pro-Ca regulates the regulation of sugar and acid balance and its impact on the production of volatile aroma substances during fruit growth and development are poorly understood. In this study, the Pro-Ca solutions developed at concentrations of 200, 400, 600 and 800 mg·L-1 were sprayed on the entire "Chardonnay" grape tree 22, 42, 62 and 82 days after initial flowering. The values of endogenous hormones, sugar and acid content, enzyme activities and flavor content were then measured in grapes 45, 65, 85 and 105 days (ripeness stage) after the initial flowering. The results showed that Pro-Ca had significant effects on fruits during development, including reducing ABA content, increasing ZT, GA3 and IAA levels, promoting fruit ripening and enhancing enzymes, which are involved in sugar and acid synthesis. Consequently, these effects led to an increase in sugar and acid content in the berries. Particularly during the ripening phase, the application of 600 mg L-1 Pro-Ca resulted in an increase in soluble sugar content of 11.28% and a significant increase in citric acid and malic acid content of 97.80% and 68.86%, respectively. Additionally, Pro-Ca treatment enhanced both the variety and quantity of aroma compounds present in the berries, with the 600 mg·L-1 Pro-Ca treatment showcasing the most favorable impact on volatile aroma compounds in 'Chardonnay' grapes. The levels of aldehydes, esters, alcohols, phenols, acids, ketones, and terpenes were significantly higher under the 600 mg·L-1 Pro-Ca treatment compared to those of control with 51.46 - 423.85% increase. In conclusion, Pro-Ca can regulate the content of endogenous hormones and the activities of enzymes related to sugar and acid metabolism in fruit, thereby increasing the content of soluble sugar and organic acid in fruit and the diversity and concentration of fruit aroma substances. Among them, foliar spraying 600 mg · L-1 Pro-Ca has the best effect. In the future, we need to further understand the molecular mechanism of Pro-Ca in grape fruit to lay a solid foundation for quality improvement breeding.


Assuntos
Vitis , Vitis/metabolismo , Frutas , Cálcio/metabolismo , Açúcares/metabolismo , Melhoramento Vegetal , Carboidratos , Hormônios/metabolismo , Hormônios/farmacologia
4.
Water Res ; 247: 120782, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37913701

RESUMO

Stormwater source controls have been adopted worldwide to address hydrological and environmental impairments caused by the spread of impervious surfaces in cities. Current design method in China uses 30-year daily rainfall records to generate relationship of rainfall volume capture ratio (αg) and daily design storm, and then uses design storm to propose design solution. However, source control performance differs from rain to rain, and hence the design solution's actual effect may deviate from αg. Borrowing closed-loop feedback concept from business domain, this study proposes closed-loop analysis (CLA) which uses design solution's 30-year simulated result as data feedback to check design solution's effectiveness and then make improvements if necessary. It consists of four methods: 1) hourly design storm statistical method, for addressing the weakness of current daily design storm; 2) design solution model credibility examination method, for guaranteeing credibility of 30-year simulated results for CLA; 3) appropriate design storms determination method for source control without underdrain; 4) additional design parameters optimization method for source control with underdrain. Taking Xiamen city for example, case study results shows that design solution's 30-year simulated results were consistent/comparable with sizing calculation formula that was used to propose design solution, and therefore they were credible for CLA. Appropriate design storms ensured design solutions without underdrain to achieve the intended αg±3 %. Optimal design parameters combinations ensured design solutions with underdrain to achieve αg but also restore natural runoff events with pre- and post-development runoff frequency spectra similarity being 0.670-0.691. Based on stormwater mathematical model, CLA can drive source control design computation to a new methodological stage.


Assuntos
Objetivos , Movimentos da Água , Cidades , Chuva , Modelos Teóricos
5.
J Environ Manage ; 335: 117563, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36867903

RESUMO

In order to find the optimal design of first flush diverter, this study shifts the focus of first flush research from the existence of first flush phenomenon to utilization effect of the phenomenon. The proposed method consists of four parts: (1) key design parameters, which describing key structure of first flush diverter rather than first flush phenomenon; (2) continuous simulation, which replicating the uncertainty by using the full scope of runoff events that might occur over the years analyzed; (3) design optimization, through an overlapped contour graph of key design parameters and key performance indicators that are relevant to but different from conventional indicators describing first flush phenomena; (4) event frequency spectra, which presenting the diverter's behavior at daily temporal resolution. As an illustration, the proposed method was used to determine design parameters of first flush diverters for roof runoff pollution control in the northeast of Shanghai. The results show that annual runoff pollution reduction ratio (PLR) was insensitive to buildup model. This greatly reduced the difficulty of buildup modeling. The contour graph was useful in finding the optimal design, i.e., the optimal combination of design parameters that could meet PLR design goal with most concentrated first flush on average (quantified by MFF). For instances, the diverter could achieve PLR = 40% with MFF >1.95, and PLR = 70% with MFF = 1.7 at most. Pollutant load frequency spectra were generated for the first time. They showed that a better design reduced pollutant load more stably while diverting less volume of first flush within almost each runoff day.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Chuva , Monitoramento Ambiental , Movimentos da Água , China , Poluentes Químicos da Água/análise , Cidades
6.
Antioxidants (Basel) ; 12(3)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36978810

RESUMO

Alcohol has been demonstrated to disrupt intestinal barrier integrity. Some flavonoid compounds that exert antioxidant activity have a protective effect on intestinal barrier function. As an important medicinal and edible plant, sea buckthorn (Hippophae) seeds are rich in flavonoids, but their protective effect on the intestinal barrier has not been reported. In our research, 76 kinds of flavonoids were identified in Hippophae rhamnoides ssp. sinensis seed residue flavonoids (HRSF) by ultra-performance liquid chromatography-tandem mass spectrometry. Kaempferol-3-O-rutinoside, isorhamnetin-3-O-rutinoside, kaempferol-3-O-robinoside-7-O-rhamnoside, isorhamnetin-3-O-2G-rhamnosylrutinoside, quercetin-3-O-rutinoside, (-)-epigallocatechin, and B type of procyanidin were the most abundant substances, accounting for 15.276%, 15.128%, 18.328%, 10.904%, 4.596%, 5.082%, and 10.079% of all identified flavonoids, respectively. Meanwhile, pre-treatment with HRSF was able to prevent alcohol-induced disruption of intestinal barrier integrity through elevating the transepithelial monolayer resistance value, inhibiting the flux of fluorescein isothiocyanate-dextran, and upregulating the mRNA and protein level of TJs (occludin and ZO-1). Furthermore, it was also able to reverse alcohol-induced oxidative stress through suppressing the accumulation of reactive oxygen species and malondialdehyde, improving the glutathione level and superoxide dismutase activity. Finally, the results showed that HRSF pre-treatment effectively elevated the erythroid-related factor 2 mRNA and protein level compared with the alcohol-alone treatment group. Our research was the first to demonstrate that HRSF could prevent alcohol-induced intestinal barrier dysfunction through regulating the Nrf2-mediated pathway in order to attenuate oxidative stress and enhance TJ expression.

7.
Plant Cell Rep ; 41(6): 1357-1373, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35316376

RESUMO

KEY MESSAGE: Most of the upregulated genes contributed to the accumulation of soluble sugars and ABA in the phloem of 'Vitis amurensis' compared to 'Merlot' during cold acclimation. Extreme cold is one of the dominant abiotic factors affecting grape yield and quality. However, the changes in sugars, phytohormones, and gene expression in the branch phloem of different tolerant grape varieties during cold acclimation remain elusive. The data supported that with decreasing temperature, the contents of fructose, sucrose, and ABA in the phloem of Vitis amurensis (cold-tolerant, T) and 'Merlot' (cold-sensitive, S) increased during cold acclimation, and these indicators were higher in T than in S. Furthermore, the activities of sucrose synthetase, sucrose phosphate synthetase, and acid invertase peaked in the early phase of cold acclimation (approximately 5 °C) compared to other phases (approximately 28 °C, 0 °C, - 5 °C and - 10 °C). Moreover, the RNA sequencing results helped identify a total of 11,343 differentially expressed genes in the phloem of T and S, among which 4912 were upregulated and 6431 were downregulated. In the abscisic acid pathway, CRTISO, PSPY1-1, CYCP707A4-2, PYL4-1, PYL4-2, P2C08, SAPK2, TARAB1, and DBF3 were more highly expressed in T than in S. In the starch and sucrose metabolism pathway, HXK1, PGMP, GLGL1, SUS6, VCINV, BGL11, SSY1, GPS, BAM1 and BAM3 were also more highly expressed in T than in S. Moreover, the genes related to oxidative phosphorylation, such as NDHF, ND4, ND1, NAD7, NAD2, ATPB, YMF19, ATP9, PMA1 and AHA8, were upregulated in T. These results will be beneficial for understanding the potential differences in tolerance across two different cold-tolerant grapes with respect to sugar metabolism and gene expression.


Assuntos
Vitis , Aclimatação/genética , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Hormônios/metabolismo , Floema/genética , Floema/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo , Temperatura , Transcriptoma/genética , Vitis/genética , Vitis/metabolismo
8.
Food Chem ; 371: 131157, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34583180

RESUMO

Ochratoxin A (OTA) is a very important mycotoxin. However, there are few studies on the removal of OTA in wine because of the great influence on product quality and difficulty in practical application. A nano-MgO-modified diatomite ceramic membrane (MCM) with a high positive charge was prepared and applied to remove OTA in wine. The isotherm adsorption between the positively charged membrane and OTA was in accordance with the Langmuir model, with a maximum adsorption capacity of 806 ng/g at 25 °C. All of the changes in adsorption enthalpy (ΔH), adsorption free energy (ΔG) and adsorption entropy (ΔS) were negative, which indicated that the combination of nano-MgO MCM and OTA was a spontaneous exothermic and nonspecific physical adsorption process. The concentrations of OTA in adsorption-treated wines were lower than 2 µg/kg, and the removal rates exceeded 92%. After OTA removal, the composition of wines was preserved to some extent.


Assuntos
Ocratoxinas , Vinho , Adsorção , Cerâmica , Ocratoxinas/análise , Eletricidade Estática , Vinho/análise
9.
BMC Plant Biol ; 21(1): 156, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33771117

RESUMO

BACKGROUND: Low temperature (LT) is one of the main limiting factors that affect growth and development in grape. Increasing soluble sugar and scavenging reactive oxygen species (ROS) play critical roles in grapevine resistance to cold stress. However, the mechanism of ß-amylase (BAM) involved in the regulation of sugar levels and antioxidant enzyme activities in response to cold stress is unclear. RESULTS: In this study, six BAM genes were identified and clustered into four groups. Multiple sequence alignment and gene structure analysis showed that VvBAM6 lacked the Glu380 residue and contained only an exon. The transcript abundance of VvBAM1 and VvBAM3 significantly increased as temperature decreased. After LT stress, VvBAM1 was highly expressed in the leaves, petioles, stems, and roots of overexpressing tomato lines. The total amylase and BAM activities increased by 6.5- and 6.01-fold in transgenic plants compared with those in wild-type tomato plants (WT) subjected to LT, respectively. The glucose and sucrose contents in transgenic plants were significantly higher than those in WT plants, whereas the starch contents in the former decreased by 1.5-fold compared with those in the latter under LT stress. The analysis of transcriptome sequencing data revealed that 541 genes were upregulated, and 663 genes were downregulated in transgenic plants. One sugar transporter protein gene (SlSTP10), two peroxidase (POD)-related genes (SlPER7 and SlPER5), and one catalase (CAT)-related gene (SlCAT1) were upregulated by 8.6-, 3.6-, 3.0-, and 2.3-fold in transgenic plants after LT stress, respectively. CONCLUSIONS: Our results suggest that VvBAM1 overexpression promotes ROS scavenging and improves cold tolerance ability by modulating starch hydrolysis to affect soluble sugar levels in tomato plants.


Assuntos
Aclimatação/genética , Genes de Plantas , Solanum lycopersicum/genética , Açúcares/metabolismo , Vitis/genética , beta-Amilase/genética , Antioxidantes/metabolismo , Expressão Ectópica do Gene , Evolução Molecular , Genoma de Planta , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiologia , Floema/metabolismo , Plantas Geneticamente Modificadas , RNA-Seq , Espécies Reativas de Oxigênio/metabolismo , Vitis/enzimologia , beta-Amilase/metabolismo
10.
Exp Ther Med ; 15(4): 3917-3923, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29563987

RESUMO

As a major cancer type in females, cervical cancer has been explored in depth by researchers. HeLa is a cervical cancer cell line. Isorhamnetin is an O-methylated flavonol that is primarily extracted from sea buckthorn. In the present study, the anti-proliferative effect of isorhamnetin on HeLa cells was evaluated using a Trypan blue dye exclusion assay. Isorhamnetin inhibited the cell proliferation in a time- and dose-dependent manner. Flow cytometric analysis of the cell cycle distribution revealed that isorhamnetin inhibited the cell cycle progression of HeLa by causing G2/M phase arrest and decreasing the proportion of cells in G1 phase. In addition, western blot analysis was performed to evaluate the presence of certain cell cycle-associated proteins. It was demonstrated that isorhamnetin inhibited the protein expression of cyclin B1, cell division cycle 25C (Cdc25C) and Cdc2, but enhanced checkpoint kinase 2 (Chk2), Cdc25C and Cdc2 phosphorylation. In addition, tubulin depolymerization participated in the isorhamnetin-induced cell cycle arrest in G2/M phase. In conclusion, the present results indicated that the anti-proliferative action of isorhamnetin is associated with arrest of the cell cycle in G2/M phase, which is a consequence of activation of the ataxia telangiectasia mutated Chk2 pathway and disruption of microtubule function.

11.
Macromol Biosci ; 4(3): 186-98, 2004 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15468208

RESUMO

The comonomer-unit compositions and their distribution of as-produced bacterial copolyesters, including poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxy-butyrate-co-3-hydroxypropionate), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) are described in this paper. Each copolyester sample can be comonomer-unit compositionally fractionated into several fractions, indicating that the original copolymers are mixtures of copolymers with different comonomer-unit compositions. The effects of comonomer-unit compositional distribution on thermal properties, crystallization, biodegradability and solid-state phase behavior are investigated using comonomer compositionally fractionated copolymers.


Assuntos
Bactérias/metabolismo , Hidroxibutiratos/química , Hidroxibutiratos/metabolismo , Poliésteres/química , Poliésteres/metabolismo , Bactérias/química , Biodegradação Ambiental , Cristalização , Hidroxibutiratos/isolamento & purificação , Poliésteres/isolamento & purificação , Termodinâmica
12.
Biomacromolecules ; 3(5): 1071-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12217055

RESUMO

The comonomer-unit compositional distributions have been investigated for bacterial poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HH)] samples with 3HH unit content of 13.8, 18.0, 22.0, and 54.0 mol %. They were comonomer compositionally fractionated using chloroform/n-heptane mixed solvent at ambient temperature. The fractionation of P(3HB-co-18.0 mol %3HH) and P(3HB-co-22.0 mol % 3HH), which could not be carried out effectively at room temperature, were refractionated at 70 degrees C in the mixed solvent. Fractions with different 3HH unit content in a wide range (from 4.4 to 80.7 mol %) were obtained. By use of these fractions with narrow compositional distribution, the comonomer composition dependence of thermal properties was investigated by differential scanning calorimetry. The melting point (T(m)) and heat of fusion (DeltaH) decreased as the 3HH unit content increased in the range of low 3HH content (<40 mol %), while they increased as the 3HH unit content increased in the high 3HH content range (>70 mol %). The minimum T(m) and DeltaH values were found to exist at 3HH unit content of about 60 mol %. The glass transition temperature (T(g)) decreased linearly with the increase of 3HH unit content. The values of T(m), DeltaH, and T(g) of P(3HB-co-3HH)s were compared with those of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxybutyrate-co-3-hydroxypropionate), and poly(3-hydroxybutyrate-co-4-hydroxybutyrate), and the effects of comonomer types on the thermal properties were revealed.


Assuntos
Ácido 3-Hidroxibutírico/química , Caproatos/química , Ácido 3-Hidroxibutírico/isolamento & purificação , Bactérias/química , Varredura Diferencial de Calorimetria , Caproatos/isolamento & purificação , Fracionamento Químico , Temperatura , Termodinâmica
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