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1.
Pak J Med Sci ; 40(4): 723-729, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38544991

RESUMO

Objective: To investigate the clinical value of the expression levels of tumor protein D52 (TPD52) and miR-133a on the prognosis assessment of pancreatic cancer surgery. Methods: This was a retrospective study. Ninety-seven patients who underwent radical surgery for pancreatic cancer in Cangzhou Central Hospital from January 2018 to January 2022 were selected and divided into four groups: TPD52 high expression group, TPD52 low expression group, miR-133a high expression group and miR-133a low expression group. The relationship between the expression levels of TPD52 and miR-133a and the clinicopathological features of patients with pancreatic cancer was analyzed. The COX regression model was used to analyze the risk factors affecting the prognosis of patients with pancreatic cancer. Results: The high expression rate of TPD52 and the low expression rate of miR-133a in pancreatic cancer tissues were higher than those in normal paracancerous tissues(P<0.05). Based on the comparison of prognosis and survival, the median survival time of patients with high expression of TPD52 and low expression of miR-133a was lower than that of patients with low expression of TPD52 and high expression of miR-133a, with a statistically significant difference(P<0.05). Moreover, multivariate Cox regression analysis showed that low differentiation of pancreatic cancer, III-IV stage of TNM, high expression of TPD52, as well as low expression of miR-133a were independent risk factors for postoperative survival of patients with pancreatic cancer(P<0.05). Conclusion: TPD52 is expressed at a high level whereas miR-133a at a low level in pancreatic cancer tissues, both of which together with low differentiation of pancreatic cancer and III-IV stage of TNM constitute independent risk factors affecting the surgical prognosis of patients with pancreatic cancer.

2.
Heliyon ; 9(11): e22084, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38058614

RESUMO

Background: Most N6-methyladenosine (m6A)-associated modulatory proteins are involved in the pathogenesis of various cancers. The roles of m6A-related genes in liver hepatocellular carcinoma (LIHC) and the associated mechanisms remain unknown. Methods: GEO and GEPIA2 databases were used to identify the m6A modification-related genes which were differentially expressed in LIHC and adjacent non-tumor tissues, and quantitative PCR was used to evaluate the expression of KIAA1429, a major m6A methyltransferase, in LIHC cells. The effect of KIAA1429 on the malignant phenotypes of LIHC cells was evaluated in vitro. The UALCAN, GEPIA, and GEO databases and western blotting assays were used to identify the target genes of KIAA1429. Results: KIAA1429 expression was markedly elevated in LIHC tissues, and patients with LIHC who had high KIAA1429 expression had a worse prognosis than those who had low expression. KIAA1429 silencing attenuated LIHC metastasis and proliferation. KIAA142 regulates m6A levels in HPN to intensify LIHC progression. Conclusion: Our study suggests a KIAA1429-HPN modulatory model based on m6A modifications, that offers insights into the occurrence and development of LIHC.

3.
Environ Sci Pollut Res Int ; 30(56): 119285-119296, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37923889

RESUMO

The global emphasis on achieving sustainable development goals necessitates the involvement of researchers and regulators worldwide. In light of this, recent research has examined the effect of human capital, renewable energy, population growth, economic growth, and environmental protection on the sustainable development goals (SDGs) in a developed economy like Pakistan, which is the most important country in the South Asian Association for Regional Cooperation (SAARC) region. This study analyzed secondary data from 1990 to 2019, using the World Development Indicators as the secondary data source. Using the augmented Dickey-Fuller test to investigate stationarity and the autoregressive distributed lag model to evaluate the nexus between variables, the researchers analyzed the relationship between the variables. The findings indicate that all predictors, such as the human capital index (HCI), renewable energy consumption, and renewable energy, exhibit a negative correlation with carbon emissions and a positive correlation with the SDGs. In this study, sustainability and the HCI are positively correlated. Reducing carbon emissions requires competent and dependable employees. As Pakistan transitions to renewable energy and strives for 30% green electricity by 2030, the report highlights the ecological benefits of controlled population growth. According to the Climate Change Performance Index (CCPI), effective climate policies advance the environmental objectives of a nation. Economic and population growth have a positive correlation with carbon emissions as well. These results facilitate Pakistani policymakers' creation of effective SDG-related initiatives for sustainable development.


Assuntos
Desenvolvimento Econômico , Desenvolvimento Sustentável , Humanos , Mudança Climática , Crescimento Demográfico , Dióxido de Carbono , Energia Renovável , Políticas , Carbono
4.
Curr Microbiol ; 80(11): 352, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737960

RESUMO

Klebsiella pneumoniae carbapenemase (KPC) is a crucial enzyme that causes carbapenem resistance in Enterobacterales, and infections by these "superbugs" are extremely challenging to treat. Therefore, there is a pressing need for a rapid and accurate KPC detection test to control the prevalence of carbapenem-resistant Enterobacterales (CREs). In this study, we established a novel method for detection of blaKPC, the gene responsible for encoding KPC, based on a recombinase polymerase amplification (RPA) and a CRISPR/Cas13a reaction coupled to fluorophore activation (termed RPA-Cas13a assay). We carefully selected a pair of optimal amplification primers for blaKPC and achieved a lower limit of detection of approximately 2.5 copies/µL by repeatedly amplifying a recombinant plasmid containing blaKPC. The RPA-Cas13a assay demonstrated a sensitivity of 96.5% and specificity of 100% when tested on 57 blaKPC-positive CRE strains, which were confirmed by DNA sequencing. Moreover, in 311 sputum samples, the theoretical antibiotic resistance characteristics of blaKPC-positive strains obtained by the RPA-Cas13a assay were highly consistent with the results of antibiotic susceptibility test (Kappa = 0.978 > 0.81, P < 0.01). In conclusion, the RPA-Cas13a system is a simple and one-hour efficient technology for the detection of a potentially fatal antibiotic resistance gene.


Assuntos
Gammaproteobacteria , Klebsiella pneumoniae , Klebsiella pneumoniae/genética , Carbapenêmicos/farmacologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Proteínas de Bactérias/genética
5.
Stress Biol ; 3(1): 28, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37676617

RESUMO

DNA damage, which may arise from cellular activities or be induced by genotoxic stresses, can cause genome instability and significantly affect plant growth and productivity. In response to genotoxic stresses, plants activate the cellular DNA damage response (DDR) to sense the stresses and activate downstream processes. The transcription factor SUPPRESSOR OF GAMMA RESPONSE 1 (SOG1), a functional counterpart of mammalian p53, is a master regulator of the DDR in plants. It is activated by various types of DNA lesions and can activate the transcription of hundreds of genes to trigger downstream processes, including cell cycle arrest, DNA repair, endoreplication, and apoptosis. Since SOG1 plays a crucial role in DDR, the activity of SOG1 must be tightly regulated. A recent study published in Plant Cell (Chen et al., Plant Cell koad126, 2023) reports a novel mechanism by which the ATR-WEE1 kinase module promotes SOG1 translation to fine-tune replication stress response.

6.
Huan Jing Ke Xue ; 44(9): 4785-4798, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699798

RESUMO

Based on 2005-2020 O3 column concentration data of OMI remote sensing satellite, combined with air pollutant data from 10 nationally controlled environmental automatic monitoring stations in the Hexi Corridor and global data assimilation system meteorological data, we used Kriging interpolation, correlation analysis, and backward trajectory (HYSPLIT) models to explore the temporal and spatial distribution characteristics, meteorological factors, transmission paths, and potential sources of O3 in the Hexi Corridor. The results showed the following:① in terms of temporal distribution, O3 column concentration showed an upward trend in 2005-2010 and 2014-2020 and downward trend in 2010-2014; the maximum and minimum values were reached in 2010 and 2014 (332.31 DU and 301.00 DU), respectively, and seasonal changes showed that those in spring and winter were significantly higher than those in summer and autumn. ② In terms of spatial distribution, O3 column concentration showed a latitudinal band distribution characteristic of increasing from southwest to northeast; the high-value areas were primarily distributed in urban areas with low terrain, and the median zone was latitudinally striped with the basic alignment of the Qilian foothills. ③ The analysis of meteorological conditions revealed that temperature, wind speed, and sunshine hours were positively correlated with O3, and relative humidity was negatively correlated with O3. ④ By simulating the airflow transportation trajectory of the receiving point in Wuwei City, it was found that the direction of the O3 conveying path was relatively singular; the dominant airflow in each season was primarily in the west and northwest; and the proportions were 71.62%, 66.85%, 61.22%, and 77.78%, respectively. There were certain seasonal differences in the source areas of O3 potential contribution:the high-value areas of O3 potential sources in spring, summer, and autumn were distributed in Baiyin City and Lanzhou City, which were southeast wind sources, and the high-value areas in winter were distributed between the Badain Jaran Desert and the Tengger Desert, which was the north wind source.

7.
Micromachines (Basel) ; 14(8)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37630155

RESUMO

In this work, we proposed a chamber-based digital PCR (cdPCR) microfluidic device that is compatible with fluorescence imaging systems for milk adulteration detection. The device enables the digitalization of PCR reagents, which are loaded into microchambers, and subsequent thermocycling for DNA amplification. Then, fluorescence images of the microchambers are captured and analyzed to obtain the total number of positive chambers, which is used to calculate the copy numbers of the target DNA, enabling accurate quantitative detections to determine intentional milk adulteration from accidental contaminations. The validation of this device is performed by camel milk authentication. We performed 25,600-chamber virtual multiplexing cdPCR tests using 40 × 40 chamber devices for the detection of DNA templates extracted from pure or mixed milk with different dilutions. Then, the cdPCR chip was used to authenticate blind milk samples, demonstrating its efficacy in real biotechnical applications.

8.
Sci Rep ; 13(1): 9440, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296194

RESUMO

Severe acute pancreatitis (SAP) presents with an aggressive clinical presentation and high lethality rate. Early prediction of the severity of acute pancreatitis will help physicians to further precise treatment and improve intervention. This study aims to construct a composite model that can predict SAP using inflammatory markers. 212 patients with acute pancreatitis enrolled from January 2018 to June 2020 were included in this study, basic parameters at admission and 24 h after hospitalization, and laboratory results such as inflammatory markers were collected. Pearson's test was used to analyze the correlation between heparin-binding protein (HBP), procalcitonin (PCT), and C-reactive protein (CRP). Risk factors affecting SAP were analyzed using multivariate logistic regression, inflammatory marker models were constructed, and subject operating curves were used to verify the discrimination of individual as well as inflammatory marker models and to find the optimal cut-off value based on the maximum Youden index. In the SAP group, the plasma levels of HBP, CRP, and PCT were 139.1 ± 74.8 ng/mL, 190.7 ± 106.3 mg/L and 46.3 ± 22.3 ng/mL, and 25.3 ± 16.0 ng/mL, 145.4 ± 67.9 mg/L and 27.9 ± 22.4 ng/mL in non-SAP patients, with a statistically significant difference between the two groups (P < 0.001), The Pearson correlation analysis showed a positive correlation between the three values of HBP, CRP, and PCT. The results of the multivariate logistic regression analysis showed that HBP (OR = 1.070 [1.044-1.098], P < 0.001), CRP (OR = 1.010 [1.004-1.016], P = 0.001), and PCT (OR = 1.030[1.007-1.053], P < 0.001) were risk factors for SAP, and the area under the curve of the HBP-CRP-PCT model was 0.963 (0.936-0.990). The HCP model, consisting of HBP, CRP, and PCT; is well differentiated and easy to use and can predict the risk of SAP in advance.


Assuntos
Pancreatite , Pró-Calcitonina , Humanos , Proteína C-Reativa/análise , Pancreatite/diagnóstico , Doença Aguda , Biomarcadores , Prognóstico
9.
J Nutr Biochem ; 117: 109355, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37085057

RESUMO

Strong evidence from observational studies shows that having body fatness is associated with an individual's risk of developing colorectal cancer (CRC), but the causality between obesity and CRC remains inadequately elucidated. Our previous studies have shown diet-induced obesity is associated with elevated TNF-α and enhanced activation of Wnt-signaling, yet the causal role of TNF-α on intestinal tumorigenesis has not been precisely studied. The present study aims to examine the functionality of TNF-α in the development of CRC associated with obesity. We first examined the extent to which diet-induced obesity elevates intestinal tumorigenesis by comparing Apc1638N mice fed a low fat diet (LFD, 10 kcal% fat) with those fed a high fat diet (HFD, 60 kcal% fat), and then investigated the degree that the genetic ablation of TNF-α attenuates the effect by crossing the TNF-α-/- mice with Apc1638N mice and feeding them with the same HFD (TNF-α KO HFD). After 16-weeks of feeding, the HFD significantly increased intestinal tumorigenesis, whereas the deletion of TNF-α attenuated the effect (P < .05). Accompanying the changes in macroscopic tumorigenesis, HFD significantly elevated intestinal inflammation and procarcinogenic Wnt-signaling, whereas abolishment of TNF-α mitigated the magnitude of these elevations (P < .05). In summary, our findings demonstrate that the knockout of TNF-α attenuates obesity-associated intestinal tumorigenesis by decreasing intestinal inflammation and thereby the Wnt-signaling, indicating that TNF-α signaling is a potential target that can be utilized to reduce the risk of CRC associated with obesity.


Assuntos
Obesidade , Fator de Necrose Tumoral alfa , Camundongos , Animais , Fator de Necrose Tumoral alfa/genética , Obesidade/genética , Carcinogênese , Dieta Hiperlipídica/efeitos adversos , Transformação Celular Neoplásica , Via de Sinalização Wnt , Inflamação/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos
10.
Plant Cell ; 35(6): 2316-2331, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-36856605

RESUMO

Apurinic/apyrimidinic (AP) sites are one of the most abundant DNA lesions and are mainly repaired by AP endonucleases (APEs). While most eukaryotic genomes encode two APEs, plants usually possess three APEs, namely APE1L, APE2, and ARP. To date, the biological relevance and functional divergence of plant APEs are unclear. Here, we show that the three plant APEs have ancient origins, with the APE1L clade being plant-specific. In Arabidopsis thaliana, simultaneously mutating APE1L and APE2, but not ARP alone or in combination with either APE1L or APE2, results in clear developmental defects linked to genotoxic stress. Genetic analyses indicated that the three plant APEs have different substrate preferences in vivo. ARP is mainly responsible for AP site repair, while APE1L and APE2 prefer to repair 3'-blocked single-stranded DNA breaks. We further determined that APEs play an important role in DNA repair and the maintenance of genomic integrity in meiotic cells. The ape1l ape2 double mutant exhibited a greatly enhanced frequency of sporulation 1 (SPO11-1)-dependent and SPO11-1-independent double-stranded DNA breaks. The DNA damage response (DDR) was activated in ape1l ape2 to trigger pollen abortion. Our findings suggest functional divergence of plant APEs and reveal important roles of plant APEs during vegetative and reproductive development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Hominidae , Animais , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Reparo do DNA/genética , Dano ao DNA/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Endonucleases/genética , Hominidae/metabolismo , Proteínas de Arabidopsis/genética
11.
Membranes (Basel) ; 13(2)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36837669

RESUMO

CO is a significant product of electrochemical CO2 reduction (ECR) which can be mixed with H2 to synthesize numerous hydrocarbons. Membranes, as separators, can significantly influence the performance of ECR. Herein, a series of quaternized polybenzimidazole (QAPBI) anion exchange membranes with different quaternization degrees are prepared for application in ECR. Among all QAPBI membranes, the QAPBI-2 membrane exhibits optimized physico-chemical properties. In addition, the QAPBI-2 membrane shows higher a Faraday efficiency and CO partial current density compared with commercial Nafion 117 and FAA-3-PK-130 membranes, at -1.5 V (vs. RHE) in an H-type cell. Additionally, the QAPBI-2 membrane also has a higher Faraday efficiency and CO partial current density compared with Nafion 117 and FAA-3-PK-130 membranes, at -3.0 V in a membrane electrode assembly reactor. It is worth noting that the QAPBI-2 membrane also has excellent ECR stability, over 320 h in an H-type cell. This work illustrates a promising pathway to obtaining cost-effective membranes through a molecular structure regulation strategy for ECR application.

12.
Micromachines (Basel) ; 14(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36838107

RESUMO

Cell viability is an essential physiological status for drug screening. While cell staining is a conventional cell viability analysis method, dye staining is usually cytotoxic. Alternatively, impedance cytometry provides a straightforward and label-free sensing approach for the assessment of cell viability. A key element of impedance cytometry is its sensing electrodes. Most state-of-the-art electrodes are made of expensive metals, microfabricated by lithography, with a typical size of ten microns. In this work, we proposed a low-cost microfluidic impedance cytometry device with 100-micron wide indium tin oxide (ITO) electrodes to achieve a comparable performance to the 10-micron wide Au electrodes. The effectiveness was experimentally verified as 7 µm beads can be distinguished from 10 µm beads. To the best of our knowledge, this is the lowest geometry ratio of the target to the sensing unit in the impedance cytometry technology. Furthermore, a cell viability test was performed on MCF-7 cells. The proposed double differential impedance cytometry device has successfully differentiated the living and dead MCF-7 cells with a throughput of ~1000 cells/s. The label-free and low-cost, high-throughput impedance cytometry could benefit drug screening, fundamental biological research and other biomedical applications.

13.
Physiol Genomics ; 55(3): 101-112, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36645669

RESUMO

Aspirin (ASA) is a proven chemoprotective agent for colorectal cancer, though mechanisms underlying these effects are incompletely understood. Human organoids are an ideal system to study genomic and epigenomic host-environment interactions. We use human colonic organoids to profile ASA responses on genome-wide gene expression and chromatin accessibility. Human colonic organoids from one individual were cultured and treated in triplicate with 3 mM ASA or vehicle control (DMSO) for 24 h. Gene expression and chromatin accessibility were measured using RNA- and ATAC-sequencing, respectively. Differentially expressed genes were analyzed using DESeq2. Top genes were validated by qPCR. Gene set enrichment was performed by SetRank. Differentially accessible peaks were analyzed using DiffBind and edgeR. Peak annotation and differential transcription factor motifs were determined by HOMER and diffTF. The results showed robust transcriptional responses to ASA with significant enrichment for fatty acid oxidation and peroxisome proliferator-activated receptor (PPAR) signaling that were validated in independent organoid lines. A large number of differentially accessible chromatin regions were found in response to ASA with significant enrichment for Fos, Jun, and Hnf transcription factor motifs. Integrated analysis of epigenomic and genomic treatment responses highlighted gene regions that could mediate ASA's specific effects in the colon including those involved in chemoprotection and/or toxicity. Assessment of chromatin accessibility and transcriptional responses to ASA yielded new observations about genome-wide effects in the colon facilitated by application of human colonic organoids. This framework can be applied to study colonic ASA responses between individuals and populations in future studies.


Assuntos
Aspirina , Epigenômica , Humanos , Aspirina/metabolismo , Colo/metabolismo , Cromatina/metabolismo , Fatores de Transcrição/metabolismo , Organoides
14.
Environ Sci Pollut Res Int ; 30(9): 23422-23436, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36322350

RESUMO

To achieve China's "double carbon" goal, it is necessary to make quantitative evaluation of the power grid enterprises' contribution to carbon emission reduction. This paper analyzes the contribution of power grid enterprises to carbon emission reduction from three points: power generation side, power grid side, and user side. Then, PLS-VIP method is used to screen the key influencing factors of carbon emission reduction contribution of power grid enterprises from three aspects: consumption of clean energy emission reduction, reduction of line loss emission reduction, and substitution of electric energy. Based on GA-ELM combined machine learning algorithm, we establish an intelligent evaluation model of power grid enterprises' carbon emission reduction contribution. Furthermore, according to the distribution law of key influencing factors, this paper uses Monte Carlo simulation method to calculate the contribution of power grid enterprises to carbon emission reduction by scenario, so as to evaluate the contribution of power grid enterprises to carbon emission reduction. Finally, combined with the relevant data of power grid enterprises from 2003 to 2019, this paper makes an empirical study on the completion of carbon emission reduction contribution and the promotion path.


Assuntos
Poluição do Ar , Carbono , Eletricidade , Carbono/análise , China , Indústrias , Poluição do Ar/prevenção & controle
15.
ISA Trans ; 136: 525-534, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36376107

RESUMO

In this study, a double-loop tracking control strategy is investigated to realize trajectory tracking control for a wheeled mobile robot (WMR) with unmodeled dynamics. More specifically, two nonlinear ESOs are designed to estimate disturbances from external disturbances and unmodeled dynamics. Combining with integral sliding mode control and backstepping control, a double-loop tracking controller is designed to enhance tracking accuracy for the WMR along the right angle roads. Based on Lyapunov methods, convergence analysis is given for both the nonlinear ESOs and the double-loop tracking controller. Validity of the double-loop tracking control strategy is demonstrated by experimental results on the WMR along a right angle road.

16.
Front Plant Sci ; 13: 910938, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755695

RESUMO

Russeting, a disorder of pear fruit skin, is mainly caused by suberin accumulation on the inner part of the outer epidermal cell layers. ABA was identified as a crucial phytohormone in suberification. Here, we demonstrated that the ABA content in russet pear skin was higher than in green skin. Then, ABA was applied to explore the changes in phenotype and suberin composition coupled with RNA-Seq and metabolomics to investigate the probably regulatory pathway of ABA-mediated suberification. The results showed that ABA treatment increased the expression of ω-3 fatty acid desaturase (FAD) and the content of α-linolenic acid. We identified 17 PbFADs in white pear, and the expression of PbFAD3a was induced by ABA. In addition, the role of PbFAD3a in promoting suberification has been demonstrated by overexpression in Arabidopsis and VIGS assays in the fruitlets. GUS staining indicated that the promoter of PbFAD3a was activated by ABA. Furthermore, MYC2 and MYB1R1 have been shown to bind to the PbFAD3a promoter directly and this was induced by ABA via yeast one-hybrid (Y1H) screening and qRT-PCR. In summary, our study found that ABA induces the expression of MYC2 and MYB1R1 and activates the PbFAD3a promoter, contributing to the formation of russet pear skin. Functional identification of key transcription factors will be the goal of future research. These findings reveal the molecular mechanism of ABA-mediated suberization in the russet skin and provide a good foundation for future studies on the formation of russet skin.

17.
Huan Jing Ke Xue ; 43(2): 1004-1014, 2022 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-35075874

RESUMO

Clarifying the absorption dynamics of heavy metal(loid)s by crops under different cultivation methods is critical for risk management and control for heavy metal pollution. Here, taking carrots as an example, the pH, cation exchange capacity (CEC), and contents of heavy metals in soil and carrots were analyzed. We compared the absorption and transport characteristics of six metal(loid)s (As, Cd, Cr, Cu, Pb, and Zn) during the three key growth periods under greenhouse and open-field cultivation methods. In addition, the effects of planting methods on carrot biomass and heavy metal content over time were studied, and a health risk assessment was conducted. The results showed that the greenhouse and open-field cultivation methods had the following in common:① As the carrots continuously grew, the metal uptake and biomass in the belowground part (edible part) and the metal(loid) concentrations in the aboveground and belowground parts both showed trends of increasing first and then decreasing or stabilizing. ② The absorption of As, Cd, Cr, and Pb in carrots was mostly accumulated in the aboveground part. ③ The content of Cd in the edible part exceeded the standard, and the total target hazard quotient was>1, indicating potential adverse health risks, most of which were contributed by As and Cd. Compared to that under open-field, the short-term greenhouse cultivation had a harvest time approximately 15 d earlier. The As, Cd, and Pb concentrations in the aboveground part during the seedling and fast-growing periods were significantly lower in the greenhouse than that in the open-field (P<0.05) but did not differ between greenhouse and open-field (except As) at the mature stage. The concentrations of As and Cd in the belowground part of greenhouse carrots were lower in the greenhouse than those of carrots grown in the open-field at the seedling stage (P<0.05). The absorption of As and Cd was decreased significantly from 0 to 95 d (P<0.05), and there was no significant difference in the metal concentration and absorption in the rest of the growth stages. The bioconcentration factors (BCF) of As, Cd, and Pb in the aboveground part in all stages and those of As and Cd in the belowground part in the seedling stage were lower in the greenhouse than that in the open-field. This study emphasizes the possibility of short-term changes in cultivation mode to reduce the risks of metal(loid)s in contaminated farmland vegetables.


Assuntos
Daucus carota , Metais Pesados , Poluentes do Solo , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise , Verduras
18.
New Phytol ; 233(2): 722-737, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655488

RESUMO

DNA methylation plays key roles in transposable element (TE) silencing and gene expression regulation. DNA methylation occurs at CG, CHG and CHH sequence contexts in plants. However, the synergistic and redundant roles of CG and non-CG methylation are poorly understood. By introducing CRISPR/Cas9-induced met1 mutation into the ddcc (drm1 drm2 cmt2 cmt3) mutant, we attempted to knock out all five DNA methyltransferases in Arabidopsis and then investigate the synergistic and redundant roles of CG and non-CG DNA methylation. We found that the homozygous ddcc met1 quintuple mutants are embryonically lethal, although met1 and ddcc mutants only display some developmental abnormalities. Unexpectedly, the ddcc met1 quintuple mutations only reduce transmission through the male gametophytes. The ddcc met1+/- mutants show apparent size divergence, which is not associated with difference in DNA methylation patterns, but associated with the difference in the levels of DNA damage. Finally, we show that a group of TEs are specifically activated in the ddcc met1+/- mutants. This work reveals that CG and non-CG DNA methylation synergistically and redundantly regulate plant reproductive development, vegetative development and TE silencing in Arabidopsis. Our findings provide insights into the roles of DNA methylation in plant development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Metilação de DNA/genética , Elementos de DNA Transponíveis/genética , Regulação da Expressão Gênica de Plantas , Desenvolvimento Vegetal
19.
Plant Cell ; 34(2): 852-866, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34791445

RESUMO

Base excision repair and active DNA demethylation produce repair intermediates with DNA molecules blocked at the 3'-OH end by an aldehyde or phosphate group. However, both the physiological consequences of these accumulated single-strand DNAs break with 3'-blocked ends (DNA 3'-blocks) and the signaling pathways responding to unrepaired DNA 3'-blocks remain unclear in plants. Here, we investigated the effects of DNA 3'-blocks on plant development using the zinc finger DNA 3'-phosphoesterase (zdp) AP endonuclease2 (ape2) double mutant, in which 3'-blocking residues are poorly repaired. The accumulation of DNA 3'-blocked triggered diverse developmental defects that were dependent on the ATM and RAD3-related (ATR)-suppressor of gamma response 1 (SOG1) signaling module. SOG1 mutation rescued the developmental defects of zdp ape2 leaves by preventing cell endoreplication and promoting cell proliferation. However, SOG1 mutation caused intensive meristematic cell death in the radicle of zdp ape2 following germination, resulting in rapid termination of radicle growth. Notably, mutating FORMAMIDOPYRIMIDINE DNA GLYCOSYLASE (FPG) in zdp ape2 sog1 partially recovered its radicle growth, demonstrating that DNA 3'-blocks generated by FPG caused the meristematic defects. Surprisingly, despite lacking a functional radicle, zdp ape2 sog1 mutants compensated the lack of root growth by generating anchor roots having low levels of DNA damage response. Our results reveal dual roles of SOG1 in regulating root establishment when seeds germinate with excess DNA 3'-blocks.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Reparo do DNA/fisiologia , Fatores de Transcrição/metabolismo , Arabidopsis/citologia , Proteínas de Arabidopsis/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Morte Celular/genética , Proliferação de Células/genética , DNA de Plantas/genética , DNA de Plantas/metabolismo , DNA-Formamidopirimidina Glicosilase/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Regulação da Expressão Gênica de Plantas , Pleiotropia Genética , Germinação/genética , Meristema/citologia , Meristema/genética , Células Vegetais , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Sementes/fisiologia , Transdução de Sinais , Fatores de Transcrição/genética
20.
Membranes (Basel) ; 11(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34940447

RESUMO

A sulfonated polyimide (SPI)/Nafion blend membrane composed of a designed and synthesized SPI polymer and the commercial Nafion polymer is prepared by a facile solution casting method for vanadium redox flow battery (VRFB). Similar molecular structures of both SPI and Nafion provide good compatibility and complementarity of the blend membrane. ATR-FTIR, 1H-NMR, AFM, and SEM are used to gain insights on the chemical structure and morphology of the blend membrane. Fortunately, the chemical stability of the SPI/Nafion blend membrane is effectively improved compared with reported SPI-based membranes for VRFB applications. In cycling charge-discharge tests, the VRFB with the as-prepared SPI/Nafion blend membrane shows excellent battery efficiencies and operational stability. Above results indicate that the SPI/Nafion blend membrane is a promising candidate for VRFB application. This work opens up a new possibility for fabricating high-performance SPI-based blend membrane by introduction of a polymer with a similar molecular structure and special functional groups into the SPI polymer.

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