RESUMO
α-Linolenic acid (ALA), an essential fatty acid (FA) for human health, serves as the precursor of 2 nutritional benefits, docosahexaenoic acid and eicosapentaenoic acid, and can only be obtained from plant foods. We previously found that phospholipid:diacylglycerol acyltransferase 2 (PrPDAT2) derived from ALA-rich tree peony (Paeonia rockii) can promote seed ALA accumulation. However, the regulatory mechanism underlying its promoting effect on ALA accumulation remains unknown. Here, we revealed a tree peony dehydration-responsive element binding transcription factor, PrDREB2D, as an upstream regulator of PrPDAT2, which is involved in regulating seed ALA accumulation. Our findings demonstrated that PrDREB2D serves as a nucleus-localized transcriptional activator that directly activates PrPDAT2 expression. PrDREB2D altered the FA composition in transient overexpression Nicotiana benthamiana leaves and stable transgenic Arabidopsis (Arabidopsis thaliana) seeds. Repressing PrDREB2D expression in P. rockii resulted in decreased PrPDAT2 expression and ALA accumulation. In addition, PrDREB2D strengthened its regulation of ALA accumulation by recruiting the cofactor ABA-response element binding factor PrABF2b. Collectively, the study findings provide insights into the mechanism of seed ALA accumulation and avenues for enhancing ALA yield via biotechnological manipulation.
Assuntos
Arabidopsis , Regulação da Expressão Gênica de Plantas , Paeonia , Proteínas de Plantas , Plantas Geneticamente Modificadas , Sementes , Fatores de Transcrição , Ácido alfa-Linolênico , Sementes/metabolismo , Sementes/genética , Ácido alfa-Linolênico/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Paeonia/genética , Paeonia/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Nicotiana/genética , Nicotiana/metabolismoRESUMO
Seed oil not only provides energy for seed postgermination development but also provides essential nutrients and raw materials for human products. However, the transcriptional regulatory mechanism controlling seed oil accumulation remains largely unknown. Tree peony (Paeonia rockii) is an emerging woody oilseed crop in China that is known for its high-quality seed oil. Here, we revealed that a tree peony nuclear factor Y transcription factor, PrNF-YC2, is expressed predominantly in developing seeds and functions as an essential positive regulator of seed oil accumulation. PrNF-YC2 promoted oil accumulation in both transient ectopic overexpression Nicotiana benthamiana leaves and stable transgenic Arabidopsis thaliana seeds, globally upregulating the expression of genes involved in oil accumulation. In contrast, PrNF-YC2-silenced tree peony leaves using a virus-induced gene silencing system showed reduced oil content and expression of oil synthesis-related genes, including four master positive regulators contributing to oil accumulation, namely, LEAFY COTYLEDON1 (LEC1), ABSCISIC ACID INSENSITIVE3 (ABI3), FUSCA3 (FUS3), and WRINKLED1 (WRI1). We demonstrated that PrNF-YC2 directly activates PrLEC1 and PrABI3 alone and indirectly activates PrFUS3 and PrWRI1 by interacting with PrLEC1. Moreover, interaction with PrLEC1 also enhances the activation capacity of PrNF-YC2. The activation of these four master positive regulators by PrNF-YC2 triggered the upregulation of numerous oil synthesis-related genes, thus promoting oil accumulation. These findings provide new insights into the regulatory mechanism of seed oil accumulation and manipulation of PrNF-YC2 may be beneficial for enhancing oil yield in tree peony and other oilseed crops.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Paeonia , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Paeonia/genética , Paeonia/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Sementes/metabolismo , Óleos de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismoRESUMO
This study aimed to characterize the effects of arsenic exposure on the expression of microsomal epoxide hydrolase (mEH or EPHX1) and soluble epoxide hydrolase (sEH or EPHX2) in the liver and small intestine. C57BL/6 mice were exposed to sodium arsenite in drinking water at various doses for up to 28 days. Intestinal, but not hepatic, mEH mRNA and protein expression was induced by arsenic at 25 ppm, in both males and females, whereas hepatic mEH expression was induced by arsenic at 50 or 100 ppm. The induction of mEH was gene specific, as the arsenic exposure did not induce sEH expression in either tissue. Within the small intestine, mEH expression was induced only in the proximal, but not the distal segments. The induction of intestinal mEH was accompanied by increases in microsomal enzymatic activities toward a model mEH substrate, cis-stilbene oxide, and an epoxide-containing drug, oprozomib, in vitro, and by increases in the levels of PR-176, the main hydrolysis metabolite of oprozomib, in the proximal small intestine of oprozomib-treated mice. These findings suggest that intestinal mEH, playing a major role in converting xenobiotic epoxides to less reactive diols, but not sEH, preferring endogenous epoxides as substrates, is relevant to the adverse effects of arsenic exposure, and that further studies of the interactions between drinking water arsenic exposure and the disposition or possible adverse effects of epoxide-containing drugs and other xenobiotic compounds in the intestine are warranted. SIGNIFICANCE STATEMENT: Consumption of arsenic-contaminated water has been associated with increased risks of various adverse health effects, such as diabetes, in humans. The small intestinal epithelial cells are the main site of absorption of ingested arsenic, but they are not well characterized for arsenic exposure-related changes. This study identified gene expression changes in the small intestine that may be mechanistically linked to the adverse effects of arsenic exposure and possible interactions between arsenic ingestion and the pharmacokinetics of epoxide-containing drugs in vivo.
Assuntos
Água Potável , Epóxido Hidrolases , Intestino Delgado , Camundongos Endogâmicos C57BL , Animais , Epóxido Hidrolases/metabolismo , Epóxido Hidrolases/genética , Camundongos , Masculino , Feminino , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/enzimologia , Arsênio/toxicidade , Arsênio/metabolismo , Arsenitos/toxicidade , Arsenitos/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Microssomos/enzimologia , Compostos de Sódio/toxicidadeRESUMO
A glucosyl-rich pectin, JMMP-3 (Mw, 2.572 × 104 g/mol, O-methyl % = 3.62%), was isolated and purified from the pericarp of the immature fruit of Juglans mandshurica Maxim. (QingLongYi). The structure of JMMP-3 was studied systematically by infrared spectroscopy, monosaccharide compositions, methylation analysis, partial acid hydrolysis, and 1/2D-NMR. The backbone of JMMP-3 possessed a smooth region (â 4GalA1 â) and a hairy region (â 4GalA1 â 2Rha1 â) with a molar ratio of 2: 5. The substitution of four characteristic side chains (R1-R4) occurs at C-4 of â 2,4)-α-Rhap-(1â, where R1 is composed of â 5)-α-Araf-(1â, R2 is composed of â 4)-ß-Galp-(1 â and ß-Galp-(1â, R3 is composed of α-Glcp-(1â, â4)-α-Glcp-(1 â and â 4,6)-α-Glcp-(1â, and R4 is composed of â 5)-α-Araf-(1â, ß-Galp-(1â, â 4)-ß-Galp-(1â, â 3,4)-ß-Galp-(1â, â 4,6)-ß-Galp-(1 â and â 2,4)-ß-Galp-(1 â . In addition, the antitumor activity of JMMP-3 on HepG2 cells was preliminarily investigated.
Assuntos
Frutas , Juglans , Pectinas , Juglans/química , Pectinas/química , Pectinas/isolamento & purificação , Humanos , Frutas/química , Células Hep G2 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificaçãoRESUMO
Some of the barriers preventing virtual reality (VR) from being widely adopted are the cost and unfamiliarity of VR systems. Here, we propose that in many cases, the specialized controllers shipped with most VR head-mounted displays can be replaced by a regular smartphone, cutting the cost of the system, and allowing users to interact in VR using a device they are already familiar with. To achieve this, we developed SmartVR Pointer, an approach that uses smartphones to replace the specialized controllers for two essential operations in VR: selection and navigation by teleporting. In SmartVR Pointer, a camera mounted on the head-mounted display (HMD) is tilted downwards so that it points to where the user will naturally be holding their phone in front of them. SmartVR Pointer supports three selection modalities: tracker based, gaze based, and combined/hybrid. In the tracker-based SmartVR Pointer selection, we use image-based tracking to track a QR code displayed on the phone screen and then map the phone's position to a pointer shown within the field of view of the camera in the virtual environment. In the gaze-based selection modality, the user controls the pointer using their gaze and taps on the phone for selection. The combined technique is a hybrid between gaze-based interaction in VR and tracker-based Augmented Reality. It allows the user to control a VR pointer that looks and behaves like a mouse pointer by moving their smartphone to select objects within the virtual environment, and to interact with the selected objects using the smartphone's touch screen. The touchscreen is used for selection and dragging. The SmartVR Pointer is simple and requires no calibration and no complex hardware assembly or disassembly. We demonstrate successful interactive applications of SmartVR Pointer in a VR environment with a demo where the user navigates in the virtual environment using teleportation points on the floor and then solves a Tetris-style key-and-lock challenge.
RESUMO
Itampolin A, a natural brominated tyrosine alkaloid isolated from the sponge Iotrochota purpurea, has been shown to have good inhibitory effects in lung cancer cells as a p38α inhibitor. A simple, sensitive, and reliable ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been established, validated, and applied to the study of the pharmacokinetics and tissue distribution of itampolin A following intragastric and intravenous administration. Itampolin A and theophylline (internal standard, IS) were extracted by the simple protein precipitation technique using methanol as the precipitating solvent. Chromatographic separation was achieved by using the optimized mobile phase of a 0.1% formic acid aqueous solution and acetonitrile in the gradient elution mode. Itampolin A and IS were detected and quantified using positive electrospray ionization in the multiple reaction monitoring mode with transitions of m/z 863.9 â 569.1 for itampolin A and m/z 181.1 â 124.1 for IS, respectively. The assay exhibited a linear dynamic range of 1-1600 ng/mL for itampolin A in biological samples and the low limit of quantification was 1 ng/mL. Non-compartmental pharmacokinetic parameters indicated that itampolin A was well-absorbed into the systemic circulation and rapidly eliminated after administration. The apparent distribution volume of itampolin A was much higher after intragastric administration than that after intravenous administration. A tissue distribution study showed that itampolin A could be detected in different tissues and maintained a high concentration in the lung, which provided a material basis for its effective application in lung cancer. The pharmacokinetic process and tissue distribution characteristics of imtapolin A were expounded in this study, which can provide beneficial information for the further research and clinical application of itampolin A.
Assuntos
Administração Intravenosa , Espectrometria de Massas em Tandem , Animais , Espectrometria de Massas em Tandem/métodos , Distribuição Tecidual , Cromatografia Líquida de Alta Pressão/métodos , Ratos , Masculino , Ratos Sprague-DawleyRESUMO
Microplastics, a new type of emerging pollutant, is ubiquitous in terrestrial and water environments. Microplastics have become a growing concern due to their impacts on the environment, animal, and human health. Birds also suffer from microplastics contamination. In this study, we examined the toxic effects of polystyrene microplastics (PS-MPs) exposure on physical barrier, microbial community, and immune function in the cecum of a model bird species-Japanese quail (Coturnix japonica). The one-week-old birds were fed on environmentally relevant concentrations of 20 µg/kg, 400 µg/kg, and 8 mg/kg PS-MPs in the diet for 5 weeks. The results showed that microplastics could cause microstructural damages characterized by lamina propria damage and epithelial cell vacuolation and ultrastructural injuries including microvilli breakage and disarrangement as well as mitochondrial vacuolation in the cecum of quails. In particular, blurry tight junctions, wider desmosomes spacing, and gene expression alteration indicated cecal tight junction malfunction. Moreover, mucous layer breakdown and mucin decrease indicated that chemical barrier was disturbed by PS-MPs. PS-MPs also changed cecal microbial diversity. In addition, structural deformation of cecal tonsils and increasing proinflammatory cytokines suggested cecal immune disorder and inflammation responses by PS-MPs exposure. Our results suggested that microplastics negatively affected digestive system and might pose great health risks to terrestrial birds.
Assuntos
Ceco , Coturnix , Microplásticos , Poliestirenos , Animais , Microplásticos/toxicidade , Poliestirenos/toxicidade , Ceco/efeitos dos fármacos , Ceco/microbiologia , Coturnix/imunologia , Microbioma Gastrointestinal/efeitos dos fármacosRESUMO
BACKGROUND: WRINKLED1 (WRI1) encodes a transcription factor, belonging to the APETALA2 (AP2) family, and plays a key role in regulating plant oil biosynthesis. As a newly woody oil crop, tree peony (Paeonia rockii) was notable for the abundant unsaturated fatty acids in its seed oil. However, the role of WRI1 during the accumulation of P. rockii seeds oil remains largely unknown. RESULTS: In this study, a new member of the WRI1 family was isolated from P. rockii and was named PrWRI1. The ORF of PrWRI1 consisted of 1269 nucleotides, encoding a putative protein of 422 amino acids, and was highly expressed in immature seeds. Subcellular localization analysis in onion inner epidermal cells showed that PrWRI1 was located at the nucleolus. Ectopic overexpression of PrWRI1 could significantly increase the total fatty acid content in Nicotiana benthamiana leaf tissue and even PUFAs in transgenic Arabidopsis thaliana seeds. Furthermore, the transcript levels of most genes related to fatty acids (FA) synthesis and triacylglycerol (TAG) assembly were also up-regulated in transgenic Arabidopsis seeds. CONCLUSIONS: Together, PrWRI1 could push carbon flow to FA biosynthesis and further enhance the TAG amount in seeds with a high proportion of PUFAs.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Paeonia , Fatores de Transcrição/genética , Paeonia/genética , Regulação da Expressão Gênica , Aminoácidos , Arabidopsis/genética , Óleos de PlantasRESUMO
BACKGROUND: Karyotype, as a basic characteristic of species, provides valuable information for fundamental theoretical research and germplasm resource innovation. However, traditional karyotyping techniques, including fluorescence in situ hybridization (FISH), are challenging and low in efficiency, especially when karyotyping aneuploid and polyploid plants. The use of low coverage whole-genome resequencing (lcWGR) data for karyotyping was explored, but existing methods are complicated and require control samples. RESULTS: In this study, a new protocol for molecular karyotype analysis was provided, which proved to be a simpler, faster, and more accurate method, requiring no control. Notably, our method not only provided the copy number of each chromosome of an individual but also an accurate evaluation of the genomic contribution from its parents. Moreover, we verified the method through FISH and published resequencing data. CONCLUSIONS: This method is of great significance for species evolution analysis, chromosome engineering, crop improvement, and breeding.
Assuntos
Aneuploidia , Poliploidia , Hibridização in Situ Fluorescente , Cariotipagem , CariótipoRESUMO
Most transgenic mouse models are generated through random integration of the transgene. The location of the transgene provides valuable information for assessing potential effects of the transgenesis on the host and for designing genotyping protocols that can amplify across the integration site, but it is challenging to identify. Here, we report the successful utility of optical genome mapping technology to identify the transgene insertion site in a CYP2A13/2B6/2F1-transgenic mouse model, which produces three human cytochrome P450 (P450) enzymes (CYP2A13, CYP2B6, and CYP2F1) that are encoded by neighboring genes on human chromosome 19. These enzymes metabolize many drugs, respiratory toxicants, and chemical carcinogens. Initial efforts to identify candidate insertion sites by whole genome sequencing was unsuccessful, apparently because the transgene is located in a region of the mouse genome that contains highly repetitive sequences. Subsequent utility of the optical genome mapping approach, which compares genome-wide marker distribution between the transgenic mouse genome and a reference mouse (GRCm38) or human (GRCh38) genome, localized the insertion site to mouse chromosome 14, between two marker positions at 4451324 base pair and 4485032 base pair. A transgene-mouse genome junction sequence was further identified through long-polymerase chain reaction amplification and DNA sequencing at GRCm38 Chr.14:4484726. The transgene insertion (â¼2.4 megabase pair) contained 5-7 copies of the human transgenes, which replaced a 26.9-33.4 kilobase pair mouse genomic region, including exons 1-4 of Gm3182, a predicted and highly redundant gene. Finally, the sequencing results enabled the design of a new genotyping protocol that can distinguish between hemizygous and homozygous CYP2A13/2B6/2F1-transgenic mice. SIGNIFICANCE STATEMENT: This study characterizes the genomic structure of, and provides a new genotyping method for, a transgenic mouse model that expresses three human P450 enzymes, CYP2A13, CYP2B6, and CYP2F1, that are important in xenobiotic metabolism and toxicity. The demonstrated success in applying the optical genome mapping technology for identification of transgene insertion sites should encourage others to do the same for other transgenic models generated through random integration, including most of the currently available human P450 transgenic mouse models.
Assuntos
Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450 , Camundongos , Animais , Humanos , Camundongos Transgênicos , Citocromo P-450 CYP2B6/genética , Sistema Enzimático do Citocromo P-450/genética , Transgenes/genética , Modelos Animais de Doenças , Mapeamento Cromossômico/métodos , Hidrocarboneto de Aril Hidroxilases/genéticaRESUMO
Polychlorinated biphenyls (PCBs) are environmental contaminants that can cause neurotoxicity. PCBs, such as PCB 95 (2,2',3,5',6-pentachlorobiphenyl), can be metabolized by cytochrome P450 enzymes into neurotoxic metabolites. To better understand how the metabolism of PCB 95 affects neurotoxic outcomes, we conducted a study on the disposition of PCB 95 in transgenic mouse models. The mice were given a single oral dose of PCB 95 (1.0 mg/kg) and were euthanized 24 h later for analysis. PCB 95 levels were highest in adipose tissue, followed by the liver, brain, and blood. Adipose tissue levels were significantly higher in wild-type (WT) mice than in Cyp2abfgs-null (KO) or CYP2A6-transgenic (KI) mice. We also observed genotype-dependent differences in the enrichment of aS-PCB 95 in female mice, with a less pronounced enrichment in KO than WT and KI mice. Ten hydroxylated PCB 95 metabolites were detected in blood and tissue across all exposure groups. The metabolite profiles differed across tissues, while sex and genotype-dependent differences were less pronounced. Total OH-PCB levels were highest in the blood, followed by the liver, adipose tissue, and brain. Total OH-PCB blood levels were lower in KO than in WT mice, while the opposite trend was observed in the liver. In male mice, total OH-PCB metabolite levels were significantly lower in KI than in WT mice in blood and the liver, while the opposite trend was observed in female mice. In conclusion, the study highlights the differences in the atropselective disposition of PCB 95 and its metabolites in different types of mice, demonstrating the usefulness of these transgenic mouse models for characterizing the role of PCB metabolism in PCB neurotoxicity.
Assuntos
Bifenilos Policlorados , Camundongos , Masculino , Feminino , Animais , Bifenilos Policlorados/toxicidade , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Fígado/metabolismo , Hidroxilação , Camundongos TransgênicosRESUMO
Co-controlling the emissions of air pollutants and CO2 from automobiles is crucial for addressing the intertwined challenges of air pollution and climate change in China. Here, we analyze the synergetic characteristics of air pollutant and CO2 emissions from China's on-road transportation and identify the co-drivers influencing these trends. Using detailed emission inventories and employing index decomposition analysis, we found that despite notable progress in pollution control, minimizing on-road CO2 emissions remains a formidable task. Over 2010-2020, the estimated sectoral emissions of VOCs, NOx, PM2.5, and CO declined by 49.9%, 25.9%, 75.2%, and 63.5%, respectively, while CO2 emissions increased by 46.1%. Light-duty passenger vehicles and heavy-duty trucks have been identified as the primary contributors to carbon-pollution co-emissions, highlighting the need for tailored policies. The driver analysis indicates that socioeconomic changes are primary drivers of emission growth, while policy controls, particularly advances in emission efficiency, can facilitate co-reductions. Regional disparities emphasize the need for policy refinement, including reducing dependency on fuel vehicles in the passenger subsector and prioritizing co-reduction strategies in high-emission provinces in the freight subsector. Overall, our study confirms the effectiveness of China's on-road control policies and provides valuable insights for future policy makers in China and other similarly positioned developing countries.
Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Emissões de Veículos/análise , Poluição do Ar/análise , China , Meios de Transporte , Monitoramento AmbientalRESUMO
Acute pancreatitis (AP) is a frequent abdominal inflammatory disease. Despite the high morbidity and mortality, the management of AP remains unsatisfactory. Disulfiram (DSF) is an FDA-proved drug with potential therapeutic effects on inflammatory diseases. In this study, we aim to investigate the effect of DSF on pancreatic acinar cell necrosis, and to explore the underlying mechanisms. Cell necrosis was induced by sodium taurocholate or caerulein, AP mice model was induced by nine hourly injections of caerulein. Network pharmacology, molecular docking, and molecular dynamics simulation were used to explore the potential targets of DSF in protecting against cell necrosis. The results indicated that DSF significantly inhibited acinar cell necrosis as evidenced by a decreased ratio of necrotic cells in the pancreas. Network pharmacology, molecular docking, and molecular dynamics simulation identified RIPK1 as a potent target of DSF in protecting against acinar cell necrosis. qRT-PCR analysis revealed that DSF decreased the mRNA levels of RIPK1 in freshly isolated pancreatic acinar cells and the pancreas of AP mice. Western blot showed that DSF treatment decreased the expressions of RIPK1 and MLKL proteins. Moreover, DSF inhibited NF-κB activation in acini. It also decreased the protein expression of TLR4 and the formation of neutrophils extracellular traps (NETs) induced by damage-associated molecular patterns released by necrotic acinar cells. Collectively, DSF could ameliorate the severity of mouse acute pancreatitis by inhibiting RIPK-dependent acinar cell necrosis and the following formation of NETs.
Assuntos
Pancreatite , Camundongos , Animais , Pancreatite/tratamento farmacológico , Pancreatite/induzido quimicamente , Células Acinares , Dissulfiram/efeitos adversos , Ceruletídeo/efeitos adversos , Doença Aguda , Simulação de Acoplamento Molecular , Necrose , Proteína Serina-Treonina Quinases de Interação com Receptores/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/uso terapêuticoRESUMO
Grasping current circumstances and influencing components of the synergistic degree regarding reducing pollution and carbon has been recognized as a crucial part of China in response to the protection of the environment and climate mitigation. With the introduction of remote sensing night-time light, CO2 emissions at multi-scale have been estimated in this study. Accordingly, an upward trend of "CO2-PM2.5" synergistic reduction was discovered, which was indicated by an increase of 78.18% regarding the index constructed of 358 cities in China from 2014 to 2020. Additionally, it has been confirmed that the reduction in pollution and carbon emissions could coordinate with economic growth indirectly. Lastly, it has identified the spatial discrepancy of influencing factors and the results have emphasized the rebound effect of technological progress and industrial upgrades, whilst the development of clean energy can offset the increase in energy consumption thus contributing to the synergy of pollution and carbon reduction. Moreover, it has been highlighted that environmental background, industrial structure, and socio-economic characteristics of different cities should be considered comprehensively in order to better achieve the goals of "Beautiful China" and "Carbon Neutrality".
Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Tecnologia de Sensoriamento Remoto , Carbono/análise , Dióxido de Carbono/análise , Cidades , China , Desenvolvimento EconômicoRESUMO
Conventional hedonic valuations of environmental amenities and cultural ecosystem services (CES) expose two limitations. First, related studies are unable to fully capture the value of visual amenity services which synergistically contribute and enhance the provision of valuable CES together with recreation, educational and spiritual services. Second, studies using linear hedonic regression cannot address potential bias resulting from multicollinearity in independent variables. We found that popular choices of covariates are correlated with the main amenity variable, which can lead to an undermined estimation precision. Therefore, to address those shortcomings, we first employed a specific proxy dummy variable to assign treatment and control individuals based on the service type. Second, we adopted propensity score matching (PSM) methodology to match treatment and control observations conditional on overlapping baseline covariates in order to avoid collinearity. Then, we carried out a comparative evaluation of a nationwide visual amenity service of the ocean ecosystem in China, via our new PSM-based average treatment effects (ATE) methodology and a conventional linear hedonic regression. Two methodologies showed opposite results, with an 8.3% premium in apartment price via PSM-ATE and a negative 0.9% premium via hedonic linear regression. Via a novel evaluation method and a nationwide case study, we conclude that diversifying and enriching the current methodology should be the priority for environmental amenity and cultural ecosystem services-related valuations.
Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , ChinaRESUMO
In this study, R-phycoerythrin (R-PE) was isolated and characterized from Porphyra yezoensis by three-phase partitioning (TPP) method. The effects of temperature, time, pH, salt saturation, and volume ratio on the purity and recovery rate of R-PE were studied. The optimum extraction conditions were determined as follows: salt saturation of 70%, temperature of 25 °C, time of 45 min, pH of 7.0, and volume ratio of 1:1. Under the optimal extraction conditions, the purity of R-PE was 3.90. The results of SDS-PAGE showed that R-PE has three bands at 23 kDa, 22 kDa, and 18 kDa, corresponding to its α, ß, γ subunits. The structure and optical activity of R-PE did not change before and after purification based on ultraviolet, infrared, and fluorescence spectra. In addition, the purity and recovery rate of R-PE extracted by tert-butanol were evaluated. The results showed that the extraction performance of tert-butanol for R-PE remained unchanged in three recoveries. These show that TPP is an efficient, green, and recyclable extraction technology.
Assuntos
Porphyra , Rodófitas , Ficoeritrina/química , terc-Butil Álcool , Rodófitas/química , Eletroforese em Gel de PoliacrilamidaRESUMO
Flavonoids are the most abundant class of secondary metabolites that are ubiquitously involved in plant development and resistance to biotic and abiotic stresses. Flavonoid biosynthesis involves multiple channels of orchestrated molecular regulatory factors. Methyl jasmonate (MeJA) has been demonstrated to enhance flavonoid accumulation in numerous plant species; however, the underlying molecular mechanism of MeJA-induced flavonoid biosynthesis in safflower is still not evident. In the present study, we revealed the underlying molecular basis of a putative F3'5'H gene from safflower imparting MeJA-induced flavonoid accumulation in transgenic plants. The constitutive expression of the CtF3'5'H1 gene was validated at different flowering stages, indicating their diverse transcriptional regulation through flower development in safflower. Similarly, the CtF3'5'H1-overexpressed Arabidopsis plants exhibit a higher expression level, with significantly increased anthocyanins and flavonoid content, but less proanthocyanidins than wild-type plants. In addition, transgenic plants treated with exogenous MeJA revealed the up-regulation of CtF3'5'H1 expression over different time points with significantly enhanced anthocyanin and flavonoid content as confirmed by HPLC analysis. Moreover, CtF3'5'H1- overexpressed Arabidopsis plants under methyl violet and UV-B irradiation also indicated significant increase in the expression level of CtF3'5'H1 with improved anthocyanin and flavonoid content, respectively. Noticeably, the virus-induced gene silencing (VIGS) assay of CtF3'5'H1 in safflower leaves also confirmed reduced anthocyanin accumulation. However, the CtF3'5'H1 suppression in safflower leaves under MeJA elicitation demonstrated significant increase in total flavonoid content. Together, our findings confirmed that CtF3'5'H1 is likely mediating methyl jasmonate-induced flavonoid biosynthesis in transgenic plants via enhanced anthocyanin accumulation.
Assuntos
Arabidopsis , Carthamus tinctorius , Antocianinas/metabolismo , Flavonoides/metabolismo , Oxigenases de Função Mista/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Carthamus tinctorius/genética , Carthamus tinctorius/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Rheumatoid arthritis(RA) is a widely prevalent autoimmune inflammatory disease that severely affects patients' quality of life. Currently, conventional formulations against RA have several limitations, such as nonspecificity, poor efficacy, large drug dosages, frequent administration, and systemic side effects. Nanotechnology-based drug delivery systems have emerged as a promising stra-tegy for the diagnosis and treatment of RA since nanotechnology can overcome the limitations of traditional treatments and simplify the complexity of the disease. These systems enable targeted delivery of anti-inflammatory drugs to the inflamed areas through active and passive targeting, achieving specificity to the joints, overcoming the need for increased dosage and administration frequency, and reducing associated adverse reactions. This article aimed to review nanocarrier-based drug delivery systems in the field of RA and elucidate how nanosystems can be utilized to deliver therapeutic drugs to inflamed joints for controlling RA progression. By discussing the current issues and challenges faced by nanodrug delivery systems and highlighting the urgent need for solutions, this article offers theoretical support for further research on nanotechnology-based co-delivery systems in the future.
Assuntos
Artrite Reumatoide , Doenças Autoimunes , Humanos , Qualidade de Vida , Sistemas de Liberação de Medicamentos , Artrite Reumatoide/tratamento farmacológico , Doenças Autoimunes/tratamento farmacológico , NanotecnologiaRESUMO
Chiral polychlorinated biphenyls (PCB) are environmentally relevant developmental neurotoxicants. Because their hydroxylated metabolites (OH-PCBs) are also neurotoxic, it is necessary to determine how PCB metabolism affects the developing brain, for example, in mouse models. Because the cytochrome P450 isoforms involved in the metabolism of chiral PCBs remain unexplored, we investigated the metabolism of PCB 91 (2,2',3,4',6-pentachlorobiphenyl), PCB 95 (2,2',3,5',6-pentachlorobiphenyl), PCB 132 (2,2',3,3',4,6'-hexachlorobiphenyl), and PCB 136 (2,2',3,3',6,6'-hexachlorobiphenyl) using liver microsomes from male and female Cyp2a(4/5)bgs-null, Cyp2f2-null, and wild-type mice. Microsomes, pooled by sex, were incubated with 50 µM PCB for 30 min, and the levels and enantiomeric fractions of the OH-PCBs were determined gas chromatographically. All four PCB congeners appear to be atropselectively metabolized by CYP2A(4/5)BGS and CYP2F2 enzymes in a congener- and sex-dependent manner. The OH-PCB metabolite profiles of PCB 91 and PCB 132, PCB congeners with one para-chlorine substituent, differed between null and wild-type mice. No differences in the metabolite profiles were observed for PCB 95 and PCB 136, PCB congeners without a para-chlorine group. These findings suggest that Cyp2a(4/5)bgs-null and Cyp2f2-null mice can be used to study how a loss of a specific metabolic function (e.g., deletion of Cyp2a(4/5)bgs or Cyp2f2) affects the toxicity of chiral PCB congeners.
Assuntos
Bifenilos Policlorados , Masculino , Feminino , Camundongos , Animais , Bifenilos Policlorados/metabolismo , Microssomos Hepáticos/metabolismo , Família 2 do Citocromo P450/metabolismo , Camundongos Transgênicos , Cloro/metabolismo , Hidroxilação , Camundongos KnockoutRESUMO
China will attempt to achieve its simultaneous goals in 2060, whereby carbon neutrality will be accomplished and the PM2.5 (fine particulate matter) level is expected to remain below 10 µg/m3. Identifying interaction patterns between air cleaning and climate action represents an important step to obtain cobenefits. Here, we used a random sampling strategy through the combination of chemical transport modeling and machine learning approach to capture the interaction effects from two perspectives in which the driving forces of both climate action and air cleaning measures were compared. We revealed that climate action where carbon emissions were decreased to 1.9 Bt (billion tons) could lead to a PM2.5 level of 12.4 µg/m3 (95% CI (confidence interval): 10.2-14.6 µg/m3) in 2060, while air cleaning could force carbon emissions to reach 1.93 Bt (95% CI: 0.79-3.19 Bt) to achieve net carbon neutrality based on the potential carbon sinks in 2060. Additional controls targeting primary PM2.5, ammonia, and volatile organic compounds were required as supplements to overcome the partial lack of climate action. Our study provides novel insights into the cobenefits of air-quality improvement and climate change mitigation, indicating that the effect of air cleaning on the simultaneous goals might have been underestimated before.