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1.
BMC Plant Biol ; 24(1): 807, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39187785

RESUMO

Cadmium (Cd) is a biologically non-essential heavy metal, a major soil pollutant, and extremely harmful to plants. The phytohormone methyl jasmonate (MeJA) plays an important role in plant heavy-metal resistance. However, the understanding of the effects of MeJA supply level on alleviating Cd toxicity in plants is limited. Here, we investigated how MeJA regulated the development of physiological processes and cell wall modification in Cosmos bipinnatus. We found that low concentrations of MeJA increased the dry weight of seedlings under 120 µM Cd stress by reducing the transport of Cd from roots to shoots. Moreover, a threshold concentration of exogenous MeJA increased the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in plant roots, the concentration of Cd in the root cell wall, and the contents of pectin and hemicellulose 1 polysaccharides, through converting Cd into pectin-bound forms. These results suggested that MeJA mitigated Cd toxicity by modulating root cell wall polysaccharide and functional group composition, especially through pectin polysaccharides binding to Cd, with effects on Cd transport capacity, specific chemical forms of Cd, and homeostatic antioxidant systems in C. bipinnatus.


Assuntos
Acetatos , Cádmio , Ciclopentanos , Oxilipinas , Reguladores de Crescimento de Plantas , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Acetatos/farmacologia , Cádmio/toxicidade , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Poluentes do Solo/toxicidade , Parede Celular/metabolismo , Parede Celular/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Antioxidantes/metabolismo , Superóxido Dismutase/metabolismo
2.
Environ Sci Technol ; 58(28): 12598-12608, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38904976

RESUMO

Understanding the transport of 137Cs emitted during the Fukushima accident is challenging because the critical emissions that produced the high-deposition area are not adequately resolved in existing source terms. This paper presents an objective inverse reconstruction of these emissions by fusing atmospheric concentrations with a-priori emissions extracted from total depositions. This extraction, previously considered impossible for complex real-world accidents, is achieved by identifying the critical temporal formation process of depositions in the high-deposition area and estimating the corresponding emissions by using an atmospheric transport model. The reconstructed source term reveals two emission peaks from 10:00-11:00 and 14:00-15:00 on March 15, which agree with the in situ pressure measurements and accident analysis, suggesting that they came from pressure drops in the primary containment vessels of Units 3 and 2, respectively. This finding explains the environmental observations of spherical 137Cs particles. The source term also objectively and independently confirms the widely used reverse estimate. The corresponding 137Cs transport simulations better match the various observations than those produced by other source terms, proving that the two-peak emission creates a high-deposition area. The proposed method outperforms the direct fusion of deposition and atmospheric concentration observations, providing a robust tool for multiobservation fusion.


Assuntos
Poluentes Radioativos do Ar , Atmosfera , Radioisótopos de Césio , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Radioisótopos de Césio/análise , Poluentes Radioativos do Ar/análise , Atmosfera/química , Japão , Modelos Teóricos
3.
Angew Chem Int Ed Engl ; : e202414104, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145688

RESUMO

Improving proton transfer is vital for electrocatalysis with porous materials. Although several strategies are reported to assist proton transfer in channels, few studies are dedicated to improving proton transfer at the local environments of active sites in porous materials. Herein, we report on new Co-corrole-based porous organic polymers (POPs) with improved proton transfer for electrocatalytic oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). By tuning the pore sizes and installing proton relays at Co corrole sites, we designed and synthesized POP-2-OH with improved proton transfer both in channels and at local Co active sites. This POP shows remarkable activity for both electrocatalytic ORR with E1/2 = 0.91 V vs RHE and OER with h10 = 255 mV. Therefore, this work is significant to present a strategy to improve active site local proton transfer in porous materials and highlight the key role of such structural functionalization in boosting oxygen electrocatalysis.

4.
Angew Chem Int Ed Engl ; 63(13): e202401074, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38311965

RESUMO

The electronic structure of metal complexes plays key roles in determining their catalytic features. However, controlling electronic structures to regulate reaction mechanisms is of fundamental interest but has been rarely presented. Herein, we report electronic tuning of Cu porphyrins to switch pathways of the hydrogen evolution reaction (HER). Through controllable and regioselective ß-oxidation of Cu porphyrin 1, we synthesized analogues 2-4 with one or two ß-lactone groups in either a cis or trans configuration. Complexes 1-4 have the same Cu-N4 core site but different electronic structures. Although ß-oxidation led to large anodic shifts of reductions, 1-4 displayed similar HER activities in terms of close overpotentials. With electrochemical, chemical and theoretical results, we show that the catalytically active species switches from a CuI species for 1 to a Cu0 species for 4. This work is thus significant to present mechanism-controllable HER via electronic tuning of catalysts.

5.
Clin Immunol ; 257: 109811, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37858752

RESUMO

BACKGROUND: To explore the specific marker of CD8+ T cell subsets which are closely related to the prognosis and immunotherapy of patients with colon cancer. METHODS: 18 kinds of immune cell expression profile data sets were obtained from GEO database. Compared with other immune cell types, the specific markers of CD8 (+) T cells (TI-CD8) in colorectal cancer were screened. Regression analyses were used to further screen prognostic related genes and construct a prognostic evaluation model. The patients were stratified and analyzed according to the risk scores, KRAS mutation status, stage, lymphatic infiltration and other indicators. The landscape of infiltration level, mutation and copy number variation of immune subsets in high and low TI-CD8Sig score groups were compared and analyzed. The difference of drug response between high and low TI-CD8Sig score groups was analyzed. Differential expression of the model genes was verified by the HPA database. RESULTS: Six prognostic-related CD8T cell-specific gene targets were further screened, and the prognostic evaluation model was constructed. The AUC value of the model is >0.75. FAT3 and UNC13C showed a high mutation state in the low-risk group, while USH2A, MUC5B et al. specifically showed a high mutation state in the high-risk group. Compared with the low-risk group, the high-risk group had lower effective rate of drug response. The expression of PD-1 gene was positively correlated with the level of TI-CD8Sig score. CONCLUSION: The risk assessment model based on CD8T cell-specific marker genes can effectively predict the prognosis and the drug response of patients with CRC.


Assuntos
Neoplasias do Colo , Variações do Número de Cópias de DNA , Humanos , Neoplasias do Colo/genética , Neoplasias do Colo/terapia , Linfócitos T CD8-Positivos , Prognóstico , Imunoterapia , Aprendizado de Máquina , Microambiente Tumoral
6.
Thromb J ; 21(1): 31, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941692

RESUMO

BACKGROUND: Platelet indices are blood-based parameters reflecting the activation of platelets. Previous studies have identified an association between platelet indices and blood pressure (BP). However, causal inferences are prone to bias by confounding effects and reverse causation. We performed a Mendelian randomization (MR) study to compare the causal roles between genetically determined platelet indices and BP levels. METHODS: Single-nucleotide polymorphisms (SNPs) associated with platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), platelet distribution width (PDW), and BP at the level of genome-wide significance (p < 5 × 10- 8) in the UK Biobank were used as instrumental variables. In bidirectional univariable MR analyses, inverse variance-weighted (IVW), MR‒Egger, and weighted median methods were used to obtain estimates for individual causal power. In addition, heterogeneity and sensitivity analyses were performed to examine the pleiotropy of effect estimates. Finally, multivariable MR analyses were undertaken to disentangle the comparative effects of four platelet indices on BP. RESULTS: In the univariable MR analyses, increased levels of PLT and PCT were associated with higher BP, and PDW was associated with higher DBP alone. In the reverse direction, SBP had a minor influence on PLT and PCT. In multivariable MR analysis, PDW and PLT revealed an independent effect, whereas the association for PCT and MPV was insignificant after colinear correction. CONCLUSION: These findings suggest that platelets and BP may affect each other. PDW and PLT are independent platelet indices influencing BP. Increased platelet activation and aggregation may be involved in the pathogenesis of hypertension, which may provide insights into evaluating thromboembolic events in people with high BP. The necessity of initiating antiplatelet therapy among hypertension groups needs further investigation.

7.
Neurol Sci ; 43(12): 6719-6730, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35982362

RESUMO

BACKGROUND: Cognitive impairment can seriously affect the quality of life of Parkinson's disease (PD) patients. Although numerous studies showed that N200, P300 latency and amplitude are correlated with cognitive functions, there is a sufficient amount of controversial results. Therefore, it is necessary to conduct a meta-analysis of N200, P300 latency and amplitude data of event-related potential (ERP) in PD. METHODS: We systematically searched on PubMed and Web of Science for PD-related ERP studies published before December 2021. Standard mean difference (SMD) and 95% confidence interval (CI) estimates of N200 and P300 components were compared among PD patients, PD dementia (PDD) patients, PD non-dementia (PDND) patient, and healthy control (HC). RESULTS: Our meta-analysis showed prolonged N200 latency at the Fz, Cz electrode sites, prolonged P300 latency at the Fz sites in PD patients, compared to HC; prolonged N200 latency at the Cz, Pz electrode sites in PDND patients, compared to HC; prolonged P300 latency at the Cz site in PDD patients, compared to PDND patients; and reduced P300 amplitude at the Fz electrode site in PDND patients, compared to HC. CONCLUSIONS: N200 and P300 component may be potential electrophysiological biomarkers of early cognitive impairment in PD patients. Future studies are needed to confirm this conclusion. Estimates of N200 and P300 component can be a valuable support for clinicians in diagnosis of early cognitive impairment in PD patients due to the simplicity and non-invasiveness of the procedure.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Humanos , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Potenciais Evocados P300/fisiologia , Potenciais Evocados/fisiologia , Qualidade de Vida
8.
BMC Oral Health ; 21(1): 596, 2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809636

RESUMO

OBJECTIVE: To provide a simplified treatment strategy for patients with maxillary transverse deficiency. We investigated and compared the fracture mechanics and stress distribution of a midline palatal suture under dynamic loads during surgically-assisted rapid palatal expansion. METHODS: Based on the cone-beam computed tomography (CBCT) data of a 21-year-old female volunteer, a three-dimensional model of the cranio-maxillofacial complex (including the palatal suture) was constructed. A finite element analysis model was constructed based on meshwork. After the yield strength of the palatal suture was set, an increasing expansion force (0-500 N) was applied within 140 ms to calculate the time-load curve, which mimicked nonsurgical bone expansion (model A). The same method was used to evaluate the fracture process, time and stress distribution of the palatal suture in maxillary lateral osteotomy-assisted (model B) and LeFort osteomy I (LFIO)-assisted expansion of the maxillary arch (model C). RESULTS: Compared with model A, the palatal suture of model B and model C showed a faster stress accumulation rate and shorter fracture time, and the fracture time of model B and model C was almost identical. Compared with model A, we discovered that model B and model C showed greater lateral extension of the maxilla, and the difference was reflected mainly in the lower part of the maxilla, and there was no difference between model B and model C in lateral extension of the maxilla. CONCLUSIONS: Compared with arch expansion using nonsurgical assistance (model A), arch expansion using maxillary lateral wall-osteotomy (model B) or LFIO had a faster rate of stress accumulation, shorter time of fracture of the palatal suture and increased lateral displacement of the maxilla. Compared with arch expansion using LFIO (model C), arch expansion using lateral osteotomy (model B) had a similar duration of palatal suture rupture and lateral maxillary extension. In view of the trauma and serious complications associated with LFIO, maxillary lateral wall-osteotomy could be considered a substitute for LFIO.


Assuntos
Maxila , Técnica de Expansão Palatina , Adulto , Feminino , Análise de Elementos Finitos , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Osteotomia Maxilar , Palato , Adulto Jovem
9.
Mar Pollut Bull ; 205: 116563, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38861800

RESUMO

This paper combines the meta-frontier analysis framework with the SBM-DEA model based on undesirable outputs to thoroughly reveal the mechanism of ecological efficiency differences in China's mariculture. This paper accurately identifies the weak links in ecological efficiency in various regions, thereby achieving a precise evaluation of mariculture ecological efficiency within the framework of technological heterogeneity. The results indicate that under the meta-frontier, the annual average ecological efficiency of mariculture in coastal areas of China during the sample period is 0.586, with a 41.4 % efficiency improvement space. However, under the group frontier, the annual average ecological efficiency is 0.783. The MEI in the BR economic zone and the YRD economic zone respectively stem from MI and TI, whereas in the PRD economic zone, the difference in the proportions of management inefficiency and technological inefficiency is not significant. Finally, this paper proposes four types of improvement paths.


Assuntos
Aquicultura , Conservação dos Recursos Naturais , China , Conservação dos Recursos Naturais/métodos , Ecossistema , Ecologia
10.
Sci Total Environ ; 920: 170955, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38354805

RESUMO

Examining the rationality of zoning designations and management measures in the initial establishment of national parks in China is of great significance for supporting decision-making regarding habitat conservation. There exists a research gap in exploring the threshold effects of both environmental and human-related factors on habitat distribution in the context of national parks. However, it may be a challenge because of the limited species distribution data. Our study aims to put forward an analytical framework that integrates species distribution models (SDMs) with interpretable machine learning methods. A case study was performed in the Sichuan region of the Giant Panda National Park (GPNP). We constructed a SDM based on the Random Forest algorithm and made use of accessible remote sensing and big data to predict the distribution of giant panda habitat (GPH) in 2020. Interpretable machine learning methods, namely Partial dependence plots (PDPs) and SHapley Additive exPlanations (SHAP), were utilized to uncover the underlying mechanisms of environmental and anthropogenic variables influencing the GPH distribution. Through GIS overlay analysis, areas where conflicts between human settlements, transportation infrastructure, and GPH exist were identified. Our findings indicated a potential 28.44 % decrease in GPH from 2014 to 2020. Environmental factors such as temperature, topography, and vegetation type, as well as anthropogenic factors including distance to built-up areas and transportation infrastructure, notably distance to national roads, provincial roads and city arterial roads, influenced the GPH distribution with threshold effects significantly. The overlay analysis revealed escalated conflicts between human settlements, transportation infrastructure, and GPH in 2020 compared to 2014. Currently, the Sichuan region of the GPNP implements two zones: a core protection zone and a general control zone, covering 63.71 % of the GPH, while 36.29 % remains outside the management scope. Drawing from the analysis above, this study provided suggestions for the adjustment of zoning designations and management measures in the GPNP.


Assuntos
Conservação dos Recursos Naturais , Ursidae , Animais , Humanos , Conservação dos Recursos Naturais/métodos , Parques Recreativos , Ecossistema , China
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