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1.
Cell ; 152(1-2): 120-31, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23332750

RESUMO

A mechanistic description of metazoan transcription is essential for understanding the molecular processes that govern cellular decisions. To provide structural insights into the DNA recognition step of transcription initiation, we used single-particle electron microscopy (EM) to visualize human TFIID with promoter DNA. This analysis revealed that TFIID coexists in two predominant and distinct structural states that differ by a 100 Å translocation of TFIID's lobe A. The transition between these structural states is modulated by TFIIA, as the presence of TFIIA and promoter DNA facilitates the formation of a rearranged state of TFIID that enables promoter recognition and binding. DNA labeling and footprinting, together with cryo-EM studies, were used to map the locations of TATA, Initiator (Inr), motif ten element (MTE), and downstream core promoter element (DPE) promoter motifs within the TFIID-TFIIA-DNA structure. The existence of two structurally and functionally distinct forms of TFIID suggests that the different conformers may serve as specific targets for the action of regulatory factors.


Assuntos
Regiões Promotoras Genéticas , Fator de Transcrição TFIID/química , Fator de Transcrição TFIID/metabolismo , Transcrição Gênica , Microscopia Crioeletrônica , DNA/genética , Humanos , Conformação Proteica , RNA Polimerase II/química , RNA Polimerase II/metabolismo , TATA Box , Fator de Transcrição TFIIA/metabolismo , Fator de Transcrição TFIID/ultraestrutura , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
2.
Mol Microbiol ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38922722

RESUMO

An arsenate reductase (Car1) from the Bacteroidetes species Rufibacter tibetensis 1351T was isolated from the Tibetan Plateau. The strain exhibits resistance to arsenite [As(III)] and arsenate [As(V)] and reduces As(V) to As(III). Here we shed light on the mechanism of enzymatic reduction by Car1. AlphaFold2 structure prediction, active site energy minimization, and steady-state kinetics of wild-type and mutant enzymes give insight into the catalytic mechanism. Car1 is structurally related to calcineurin-like metallophosphoesterases (MPPs). It functions as a binuclear metal hydrolase with limited phosphatase activity, particularly relying on the divalent metal Ni2+. As an As(V) reductase, it displays metal promiscuity and is coupled to the thioredoxin redox cycle, requiring the participation of two cysteine residues, Cys74 and Cys76. These findings suggest that Car1 evolved from a common ancestor of extant phosphatases by incorporating a redox function into an existing MPP catalytic site. Its proposed mechanism of arsenate reduction involves Cys74 initiating a nucleophilic attack on arsenate, leading to the formation of a covalent intermediate. Next, a nucleophilic attack of Cys76 leads to the release of As(III) and the formation of a surface-exposed Cys74-Cys76 disulfide, ready for reduction by thioredoxin.

3.
Brief Bioinform ; 24(4)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37249547

RESUMO

Pathogen detection from biological and environmental samples is important for global disease control. Despite advances in pathogen detection using deep learning, current algorithms have limitations in processing long genomic sequences. Through the deep cross-fusion of cross, residual and deep neural networks, we developed DCiPatho for accurate pathogen detection based on the integrated frequency features of 3-to-7 k-mers. Compared with the existing state-of-the-art algorithms, DCiPatho can be used to accurately identify distinct pathogenic bacteria infecting humans, animals and plants. We evaluated DCiPatho on both learned and unlearned pathogen species using both genomics and metagenomics datasets. DCiPatho is an effective tool for the genomic-scale identification of pathogens by integrating the frequency of k-mers into deep cross-fusion networks. The source code is publicly available at https://github.com/LorMeBioAI/DCiPatho.


Assuntos
Algoritmos , Software , Humanos , Redes Neurais de Computação , Genoma , Genômica
4.
Mol Ther ; 32(2): 469-489, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38098230

RESUMO

Macrophages play a crucial role in shaping the immune state within the tumor microenvironment (TME) and are often influenced by tumors to hinder antitumor immunity. However, the underlying mechanisms are still elusive. Here, we observed abnormal expression of complement 5a receptor (C5aR) in human ovarian cancer (OC), and identified high levels of C5aR expression on tumor-associated macrophages (TAMs), which led to the polarization of TAMs toward an immunosuppressive phenotype. C5aR knockout or inhibitor treatment restored TAM antitumor response and attenuated tumor progression. Mechanistically, C5aR deficiency reprogrammed macrophages from a protumor state to an antitumor state, associating with the upregulation of immune response and stimulation pathways, which in turn resulted in the enhanced antitumor response of cytotoxic T cells in a manner dependent on chemokine (C-X-C motif) ligand 9 (CXCL9). The pharmacological inhibition of C5aR also improved the efficacy of immune checkpoint blockade therapy. In patients, C5aR expression associated with CXCL9 production and infiltration of CD8+ T cells, and a high C5aR level predicted poor clinical outcomes and worse benefits from anti-PD-1 therapy. Thus, our study sheds light on the mechanisms underlying the modulation of TAM antitumor immune response by the C5a-C5aR axis and highlights the potential of targeting C5aR for clinical applications.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Quimiocina CXCL9/genética , Imunidade , Neoplasias/patologia , Receptor da Anafilatoxina C5a/genética , Microambiente Tumoral , Macrófagos Associados a Tumor/metabolismo , Feminino
5.
Mol Cell Proteomics ; 22(8): 100602, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37343696

RESUMO

Treatment and relevant targets for breast cancer (BC) remain limited, especially for triple-negative BC (TNBC). We identified 6091 proteins of 76 human BC cell lines using data-independent acquisition (DIA). Integrating our proteomic findings with prior multi-omics datasets, we found that including proteomics data improved drug sensitivity predictions and provided insights into the mechanisms of action. We subsequently profiled the proteomic changes in nine cell lines (five TNBC and four non-TNBC) treated with EGFR/AKT/mTOR inhibitors. In TNBC, metabolism pathways were dysregulated after EGFR/mTOR inhibitor treatment, while RNA modification and cell cycle pathways were affected by AKT inhibitor. This systematic multi-omics and in-depth analysis of the proteome of BC cells can help prioritize potential therapeutic targets and provide insights into adaptive resistance in TNBC.


Assuntos
Transdução de Sinais , Neoplasias de Mama Triplo Negativas , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteômica , Proliferação de Células , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Receptores ErbB/metabolismo
6.
J Am Chem Soc ; 146(19): 13356-13366, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38602480

RESUMO

The crucial roles that glycans play in biological systems are determined by their structures. However, the analysis of glycan structures still has numerous bottlenecks due to their inherent complexities. The nanopore technology has emerged as a powerful sensor for DNA sequencing and peptide detection. This has a significant impact on the development of a related research area. Currently, nanopores are beginning to be applied for the detection of simple glycans, but the analysis of complex glycans by this technology is still challenging. Here, we designed an engineered α-hemolysin nanopore M113R/T115A to achieve the sensing of complex glycans at micromolar concentrations and under label-free conditions. By extracting characteristic features to depict a three-dimensional (3D) scatter plot, glycans with different numbers of functional groups, various chain lengths ranging from disaccharide to decasaccharide, and distinct glycosidic linkages could be distinguished. Molecular dynamics (MD) simulations show different behaviors of glycans with ß1,3- or ß1,4-glycosidic bonds in nanopores. More importantly, the designed nanopore system permitted the discrimination of each glycan isomer with different lengths in a mixture with a separation ratio of over 0.9. This work represents a proof-of-concept demonstration that complex glycans can be analyzed using nanopore sequencing technology.


Assuntos
Simulação de Dinâmica Molecular , Nanoporos , Polissacarídeos , Polissacarídeos/química , Proteínas Hemolisinas/química , Engenharia de Proteínas
7.
J Am Chem Soc ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859580

RESUMO

In the realm of organic synthesis, the catalytic and stereoselective formation of C-glycosidic bonds is a pivotal process, bridging carbohydrates with aglycones. However, the inherent chirality of the saccharide scaffold often has a substantial impact on the stereoinduction imposed by a chiral ligand. In this study, we have established an unprecedented zirconaaziridine-mediated asymmetric nickel catalysis, enabling the diastereoselective coupling of bench-stable glycosyl phosphates with a range of (hetero)aromatic and glycal iodides as feasible coupling electrophiles. Our developed method showcases a broad scope and a high tolerance for various functional groups. More importantly, precise stereocontrol toward both anomeric configurations of forming C(sp2)-glycosides can be realized by simply utilizing the popular chiral bioxazoline (biOx) ligands in this reductive Ni catalysis. Regarding the operating mechanism, both experimental and computational studies support the occurrence of a redox transmetalation process, leading to the formation of a transient, bimetallic Ni-Zr species that acts as a potent and efficient single-electron reductant in the catalytic process.

8.
Small ; 20(23): e2307603, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38213024

RESUMO

Bacterial cellulose/oxidized bacterial cellulose nanofibrils (BC/oxBCNFs) macro-fibers are developed as a novel scaffold for vascular tissue engineering. Utilizing a low-speed rotary coagulation spinning technique and precise solvent control, macro-fibers with a unique heterogeneous structure with dense surface and porous core are created. Enhanced by a polydopamine (PDA) coating, these macro-fibers offer robust mechanical integrity, high biocompatibility, and excellent cell adhesion. When cultured with endothelial cells (ECs) and smooth muscle cells (SMCs), the macro-fibers support healthy cell proliferation and exhibit a unique spiral SMC alignment, demonstrating their vascular suitability. This innovative strategy opens new avenues for advances in tissue engineering.


Assuntos
Celulose , Nanofibras , Engenharia Tecidual , Alicerces Teciduais , Engenharia Tecidual/métodos , Nanofibras/química , Alicerces Teciduais/química , Celulose/química , Humanos , Miócitos de Músculo Liso/citologia , Proliferação de Células/efeitos dos fármacos , Adesão Celular , Células Endoteliais/citologia , Células Endoteliais da Veia Umbilical Humana , Indóis/química , Polímeros
9.
New Phytol ; 242(6): 2604-2619, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563391

RESUMO

Soil contamination with arsenic (As) can cause phytotoxicity and reduce crop yield. The mechanisms of As toxicity and tolerance are not fully understood. In this study, we used a forward genetics approach to isolate a rice mutant, ahs1, that exhibits hypersensitivity to both arsenate and arsenite. Through genomic resequencing and complementation tests, we identified OsLPD1 as the causal gene, which encodes a putative lipoamide dehydrogenase. OsLPD1 was expressed in the outer cell layer of roots, root meristem cells, and in the mesophyll and vascular tissues of leaves. Subcellular localization and immunoblot analysis demonstrated that OsLPD1 is localized in the stroma of plastids. In vitro assays showed that OsLPD1 exhibited lipoamide dehydrogenase (LPD) activity, which was strongly inhibited by arsenite, but not by arsenate. The ahs1 and OsLPD1 knockout mutants exhibited significantly reduced NADH/NAD+ and GSH/GSSG ratios, along with increased levels of reactive oxygen species and greater oxidative stress in the roots compared with wild-type (WT) plants under As treatment. Additionally, loss-of-function of OsLPD1 also resulted in decreased fatty acid concentrations in rice grain. Taken together, our finding reveals that OsLPD1 plays an important role for maintaining redox homeostasis, conferring tolerance to arsenic stress, and regulating fatty acid biosynthesis in rice.


Assuntos
Arsênio , Ácidos Graxos , Regulação da Expressão Gênica de Plantas , Homeostase , Oryza , Oxirredução , Proteínas de Plantas , Plastídeos , Estresse Fisiológico , Oryza/genética , Oryza/efeitos dos fármacos , Oryza/metabolismo , Homeostase/efeitos dos fármacos , Arsênio/toxicidade , Oxirredução/efeitos dos fármacos , Ácidos Graxos/metabolismo , Ácidos Graxos/biossíntese , Plastídeos/metabolismo , Plastídeos/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Mutação/genética , Di-Hidrolipoamida Desidrogenase/metabolismo , Di-Hidrolipoamida Desidrogenase/genética , Espécies Reativas de Oxigênio/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Estresse Oxidativo/efeitos dos fármacos , Arsenitos/toxicidade
10.
Plant Physiol ; 191(3): 1520-1534, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36423229

RESUMO

The concentration, chemical speciation, and spatial distribution of essential and toxic mineral elements in cereal seeds have important implications for human health. To identify genes responsible for element uptake, translocation, and storage, high-throughput phenotyping methods are needed to visualize element distribution and concentration in seeds. Here, we used X-ray fluorescence microscopy (µ-XRF) as a method for rapid and high-throughput phenotyping of seed libraries and developed an ImageJ-based pipeline to analyze the spatial distribution of elements. Using this method, we nondestructively scanned 4,190 ethyl methanesulfonate (EMS)-mutagenized M1 rice (Oryza sativa) seeds and 533 diverse rice accessions in a genome-wide association study (GWAS) panel to simultaneously measure concentrations and spatial distribution of elements in the embryo, endosperm, and aleurone layer. A total of 692 putative mutants and 65 loci associated with the spatial distribution of elements in rice seed were identified. This powerful method provides a basis for investigating the genetics and molecular mechanisms controlling the accumulation and spatial variations of mineral elements in plant seeds.


Assuntos
Estudo de Associação Genômica Ampla , Oryza , Humanos , Raios X , Sementes/genética , Minerais , Microscopia de Fluorescência , Oryza/genética
11.
Plant Cell Environ ; 47(6): 2163-2177, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38481060

RESUMO

Copper (Cu) is an essential micronutrient for all living organisms but is also highly toxic in excess. Cellular homoeostasis of Cu is maintained by various transporters and metallochaperones. Here, we investigated the biological function of OsCOPT7, a member of the copper transporters (COPT) family, in Cu homoeostasis in rice. OsCOPT7 was mainly expressed in the roots and the expression was upregulated by Cu deficiency. OsCOPT7 was localized at the tonoplast and the endoplasmic reticulum. Knockout of OsCOPT7 increased Cu accumulation in the roots but decreased Cu concentrations in the shoots and grain. The knockout mutants contained higher concentrations of Cu in the roots cell sap but markedly lower concentrations of Cu in the xylem sap than wild-type plants. Seed setting and grain yield were reduced significantly in the knockout mutants grown in a low Cu soil. Knockout mutants were more tolerant to Cu toxicity. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that OsCOPT7 interacts physically with the rice Cu chaperone antioxidant protein 1 (OsATX1). Taken together, our results indicate that OsCOPT7 is a specific Cu transporter functioning to export Cu from the vacuoles and the ER and plays an important role in controlling the root-to-shoot Cu translocation in rice.


Assuntos
Cobre , Retículo Endoplasmático , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Transporte Biológico , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Cobre/metabolismo , Grão Comestível/metabolismo , Grão Comestível/genética , Retículo Endoplasmático/metabolismo , Técnicas de Inativação de Genes , Oryza/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Sementes/metabolismo , Sementes/genética , Vacúolos/metabolismo
12.
Plant Cell Environ ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828861

RESUMO

Cadmium (Cd) is a toxic metal that poses serious threats to human health. Rice is a major source of dietary Cd but how rice plants transport Cd to the grain is not fully understood. Here, we characterize the function of the ZIP (ZRT, IRT-like protein) family protein, OsZIP2, in the root-to-shoot translocation of Cd and intervascular transfer of Cd in nodes. OsZIP2 is localized at the plasma membrane and exhibited Cd2+ transport activity when heterologously expressed in yeast. OsZIP2 is strongly expressed in xylem parenchyma cells in roots and in enlarged vascular bundles in nodes. Knockout of OsZIP2 significantly enhanced root-to-shoot translocation of Cd and alleviated the inhibition of root elongation by excess Cd stress; whereas overexpression of OsZIP2 decreased Cd translocation to shoots and resulted in Cd sensitivity. Knockout of OsZIP2 increased Cd allocation to the flag leaf but decreased Cd allocation to the panicle and grain. We further reveal that the variation of OsZIP2 expression level contributes to grain Cd concentration among rice germplasms. Our results demonstrate that OsZIP2 functions in root-to-shoot translocation of Cd in roots and intervascular transfer of Cd in nodes, which can be used for breeding low Cd rice varieties.

13.
J Vasc Surg ; 79(2): 330-338, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37802401

RESUMO

OBJECTIVE: We retrospectively compared the clinical outcomes of self-expanding covered stents (CSs) and bare metal stents (BMSs) in the treatment of aortoiliac occlusive disease (AIOD) at a single center between 2016 and 2022. METHODS: All patients with AIOD receiving endovascular therapy at a single center from January 2016 to October 2022 were continuously analyzed, including patients with lesions of all classes according to the Trans-Atlantic Inter-Society Consensus II (TASC-II). Relevant clinical and baseline data were collected, and propensity score matching was performed to compare CSs and BMSs in terms of baseline characteristics, surgical factors, 30-day outcomes, 5-year primary patency, and limb salvage. The follow-up results were analyzed by Kaplan-Meier curves. Cox proportional hazard models were used to identify predictors of primary patency. RESULTS: A total of 209 patients with AIOD were enrolled in the study, including 135 patients (64.6%) in the CS group and 74 patients (35.4%) in the BMS group. Surgical success rates (100% vs 100%; P = 1.00), early (<30-day) mortality rates (0% vs 0%; P = 1.00), cumulative surgical complication rate (12.0% vs 8.0%; P = .891), 5-year primary patency rate (83.4% vs 86.9%; P = .330), secondary patency rate (96% vs 100%; P = .570), and limb salvage rate (100% vs 100%; P = 1.00) did not exhibit significant differences between the two groups. Patients in the CS group had a lower preoperative ankle-brachial index (0.48 ± 0.26 vs 0.52 ± 0.19; P = .032), more cases of complex AIOD (especially TASC D) (47.4% vs 9.5%; P < .001), more chronic total occlusive lesions (77.0% vs 31.1%; P < .001), and more severe calcification (20.7% vs 14.9%; P < .036). After propensity score matching, 50 patients (25 with CS and 25 with BMS) were selected. The results showed that only severe calcification (32.0% vs 8.0%; P = .034) and ankle-brachial index increase (0.45 ± 0.15 vs 0.41 ± 0.22; P = .038) were significantly different between the groups. In terms of surgical factors, patients in the CS group had more use of bilateral femoral or combined brachial artery percutaneous access (60.0% vs 12.0%; P < .001), more number of stents used (2.3 ± 1.2 vs 1.3 ± 0.7; P < .001), longer mean stent length (9.3 ± 3.3 vs 5.8 ± 2.6 cm; P < .001), and more catheter-directed thrombolysis treatment (32.0% vs 4.0%; P = .009). Multivariate Cox survival analysis showed that severe calcification (hazard ratio, 1.32; 95% confidence interval, 1.04-1.85; P = .048) was the only independent predictor of the primary patency rate. CONCLUSIONS: All patients with AIOD who underwent endovascular therapy were included and achieved good outcomes with both CSs and BMSs. The influence of confounding factors in the two groups was minimized by propensity score matching, and the 5-year patency rates were generally similar in the unmatched and matched cohorts. Postoperative hemodynamic improvement was more obvious in patients in the CS group. For more complex lesions, CS is recommended to be preferred. Especially for severe calcification lesions, which is the only independent predictor of primary patency, CS showed obvious advantages. Further studies with more samples are needed to investigate the role of stent types in AIOD treatment.


Assuntos
Arteriopatias Oclusivas , Aterosclerose , Humanos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Stents , Grau de Desobstrução Vascular , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/cirurgia , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/cirurgia , Desenho de Prótese
14.
J Exp Bot ; 75(1): 438-453, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721748

RESUMO

Cadmium (Cd) is highly toxic to plants, but the targets and modes of toxicity remain unclear. We isolated a Cd-hypersensitive mutant of Arabidopsis thaliana, Cd-induced short root 2 (cdsr2), in the background of the phytochelatin synthase-defective mutant cad1-3. Both cdsr2 and cdsr2 cad1-3 displayed shorter roots and were more sensitive to Cd than their respective wild type. Using genomic resequencing and complementation, IAR4 was identified as the causal gene, which encodes a putative mitochondrial pyruvate dehydrogenase E1α subunit. cdsr2 showed decreased pyruvate dehydrogenase activity and NADH content, but markedly increased concentrations of pyruvate and alanine in roots. Both Cd stress and IAR4 mutation decreased auxin level in the root tips, and the effect was additive. A higher growth temperature rescued the phenotypes in cdsr2. Exogenous alanine inhibited root growth and decreased auxin level in the wild type. Cadmium stress suppressed the expression of genes involved in auxin biosynthesis, hydrolysis of auxin-conjugates and auxin polar transport. Our results suggest that auxin homeostasis is a key target of Cd toxicity, which is aggravated by IAR4 mutation due to decreased pyruvate dehydrogenase activity. Decreased auxin level in cdsr2 is likely caused by increased auxin-alanine conjugation and decreased energy status in roots.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Cádmio/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Homeostase , Mutação , Ácidos Indolacéticos/metabolismo , Alanina , Piruvatos/metabolismo , Piruvatos/farmacologia , Oxirredutases/metabolismo , Raízes de Plantas/metabolismo
15.
Opt Lett ; 49(12): 3300-3303, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38875605

RESUMO

Optical path length (OPL) noise resulting from stray light significantly constrains interferometry displacement measurements in the low-frequency band. This paper presents an analytical model considering the presence of stray light in heterodyne laser interferometers. Due to the cyclic nonlinear coupling effect, there will be some special OPLs of stray light, minimizing the frequency-mixing impact to zero. Consequently, we propose a noise suppression scheme that locks the OPL of stray light at the zero coupling point. Therefore, we significantly enhanced the interference displacement measurement noise within the low-frequency band. Experimental results show that the interferometer achieves a displacement noise level lower than 6 pm/Hz1/2 covering 1 mHz.

16.
Langmuir ; 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38343075

RESUMO

Investigation of asphaltene adsorption at rock surfaces plays an important role in enhanced oil recovery (EOR) for the petroleum industry. In this work, the interaction performances of asphaltene adsorption at carbonate dolomite and calcite surfaces are investigated based on experimental and simulation insights. On the one hand, macroscopic interaction performances were investigated by spectroscopy experiments to obtain the Langmuir thermodynamic model and pseudo-second-order (PSO) kinetic model. The results indicated monolayer molecular asphaltene adsorption for both dolomite and calcite, while they showed 'slow adsorption-slow desorption' for dolomite but 'fast adsorption-fast desorption' for calcite. Meanwhile, dolomite showed a higher adsorption capacity with qm(dol 1) = 5.35 mg/g > qm(cal 1) = 1.28 mg/g and a stronger adsorption spontaneity with ΔGm(dol 1)θ = -7.76 kJ/mol < ΔGm(cal 1)θ = -4.76 kJ/mol. On the other hand, microscopic interaction performances were investigated for three asphaltene molecules by molecular dynamics simulation (MDS) with ∼8 Å distance-placing and 500 ps time-running. According to the results, dolomite showed higher system stability than calcite with a lower final energy of ΔEdol-cal = -58 kJ/mol, and archipelago asphaltene showed higher adsorption stability with the smallest equilibrium energy of Earch(dol) = -147 kJ/mol for albite and Earch(cal) = -89 kJ/mol for calcite. The model of molecular orientation and force dominance was proposed as the interaction mechanism for asphaltene adsorption, which "lie sideways" at low concentrations but "stands upright" at high concentrations. This work allows the performance investigation and mechanism illustration of asphaltene adsorption at rock surfaces, which can help gain a fundamental understanding of the EOR during reservoir exploitation.

17.
J Endovasc Ther ; : 15266028231224249, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38284343

RESUMO

PURPOSE: To observe the short-term efficacy of thoracic endovascular aortic repair (TEVAR) using a single left common carotid artery chimney stent combined with a Castor single-branched stent-graft (SC-TEVAR) in the treatment of zone 2 (Z2) aortic diseases. MATERIALS AND METHODS: To conduct a retrospective analysis of 20 patients with Z2 aortic diseases who were treated in our department from June 2021 to April 2022. The lesions included true aortic degenerative aneurysms with diameter ≥5.0 cm and penetrating aortic ulcers with depth >1.0 cm or basal width >2.0 cm. All 20 patients accepted the SC-TEVAR treatment, which was a new hybrid method to assure the flow of the left common carotid artery (LCCA) and left subclavian artery (LSA). This method was defined as a concomitant chimney stent for LCCA and a Castor single-branched stent graft for the aorta and LSA. The baseline data and intraoperative data were collected to evaluate the safety and efficacy of this method. The patency of the target blood vessel and any associated complications were evaluated at 1 and 6 months postoperatively, to analyze the safety and efficacy of this new method. RESULTS: After discharge from the hospital, all patients were followed up by a specific follow-up team. At 6 monthly follow-up period, there were no cardiac events, stroke, hemiplegia, type I endoleak, type II endoleak, proximal stent graft-induced new entries, distal stent graft-induced new entries, wound infection, or bleeding. Only 1 patient developed an inguinal wound hematoma and got conservative treatment. Importantly, no patients developed stenosis or occlusion of the LCCA or LSA. The patency of branched arteries was 100%. The technical success rate was 90%. CONCLUSION: SC-TEVAR appears to be a new and relatively simple, safe, and effective treatment for Z2 aortic diseases. CLINICAL IMPACT: This was a single-center retrospective cohort study. A total of 20 patients with zone 2 aortic diseases accepted a new hybrid surgical method named SC-TEVAR. This method was not complicated and could be finished with only 3 peripheral artery exposure. The result showed no mortality, 100% patency of the branch artery, and 90% of technical success in 6 months of follow-up time. SC-TEVAR showed a satisfactory result in this retrospective study and could be promoted as an easy method to treat zone 2 aortic diseases.

18.
Environ Sci Technol ; 58(4): 1976-1985, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38232111

RESUMO

Rice is a dominant source of inorganic arsenic (As) exposure for populations consuming rice as a staple food. Decreasing As accumulation in rice grain is important for improving food safety. Arsenite [As(III)], the main form of As in paddy soil porewater, is taken up inadvertently by OsLsi1 and OsLsi2, the two key transporters for silicon (Si) uptake in rice roots. Here, we investigated whether editing OsLsi1 or OsLsi2 can decrease As accumulation in rice grain without compromising grain yield. We used the CRISPR-Cas9 technology to edit the promoter region of OsLsi1 and the C-terminal coding sequence of OsLsi1 and OsLsi2, and we generated a total of 27 mutants. Uptake and accumulation of Si and As were evaluated in both short-term hydroponic experiments and in a paddy field. Deletion of 1.2-2 kb of the OsLsi1 promoter suppressed OsLsi1 expression in roots and Si uptake markedly and did not affect As(III) uptake or grain As concentration. Some of the OsLsi1 and OsLsi2 coding sequence mutants showed large decreases in the uptake of Si and As(III) as well as large decreases in Si accumulation in rice husks. However, only OsLsi2 mutants showed significant decreases (by up to 63%) in the grain total As concentration. Editing OsLsi2 mainly affected the accumulation of inorganic As in rice grain with little effect on the accumulation of dimethylarsenate (DMA). Grain yields of the OsLsi2 mutants were comparable to those of the wild type. Editing OsLsi2 provides a promising way to reduce As accumulation in rice grain without compromising the grain yield.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Silício/metabolismo , Oryza/genética , Proteínas de Membrana Transportadoras , Transporte Biológico , Solo
19.
Environ Sci Technol ; 58(18): 7880-7890, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38670926

RESUMO

Flooding of paddy fields during the rice growing season enhances arsenic (As) mobilization and greenhouse gas (e.g., methane) emissions. In this study, an adsorbent for dissolved organic matter (DOM), namely, activated carbon (AC), was applied to an arsenic-contaminated paddy soil. The capacity for simultaneously alleviating soil carbon emissions and As accumulation in rice grains was explored. Soil microcosm incubations and 2-year pot experimental results indicated that AC amendment significantly decreased porewater DOM, Fe(III) reduction/Fe2+ release, and As release. More importantly, soil carbon dioxide and methane emissions were mitigated in anoxic microcosm incubations. Porewater DOM of pot experiments mainly consisted of humic-like fluorophores with a molecular structure of lignins and tannins, which could mediate microbial reduction of Fe(III) (oxyhydr)oxides. Soil microcosm incubation experiments cospiking with a carbon source and AC further consolidated that DOM electron shuttling and microbial carbon source functions were crucial for soil Fe(III) reduction, thus driving paddy soil As release and carbon emission. Additionally, the application of AC alleviated rice grain dimethylarsenate accumulation over 2 years. Our results highlight the importance of microbial extracellular electron transfer in driving paddy soil anaerobic respiration and decreasing porewater DOM in simultaneously remediating As contamination and mitigating methane emission in paddy fields.


Assuntos
Arsênio , Carbono , Oryza , Solo , Arsênio/metabolismo , Solo/química , Poluentes do Solo , Carvão Vegetal/química , Metano
20.
Eur J Nutr ; 63(4): 1113-1124, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38345640

RESUMO

PURPOSE: The associations between dietary patterns and liver cancer risk have received much attention, but evidence among the Chinese population is scarce. This study aims to update the results of two cohort studies and provide the sex-specific associations in the Chinese population. METHODS: This study was based on two cohorts from the Shanghai Men's Health Study (SMHS) and the Shanghai Women's Health Study (SWHS). Diet information was collected by validated food frequency questionnaires. Dietary patterns were derived by factor analysis. Cox regression model was utilized to estimate the hazard ratio (HR) and 95% confidence interval (CI) for associations between dietary patterns and liver cancer risk. RESULTS: During median follow-up years of 11.2 (male) and 17.1 (female) years, 427 males and 252 females were identified as incident primary liver cancer cases. In males, vegetable-based dietary pattern was inversely associated with liver cancer (HRQ4-Q1: 0.67, 95%CI 0.51-0.88, Ptrend < 0.001). Interaction analysis indicated that in males lower vegetable-based dietary pattern score and older age/medical history of chronic hepatitis combined increase the hazard of liver cancer more than the sum of them, with a 114% and 1061% higher risk, respectively. In females, the fruit-based dietary pattern was associated with a reduced risk of liver cancer (HRQ4-Q1: 0.63, 95%CI 0.42-0.95, Ptrend = 0.03). In both males and females, null associations were observed between the meat-based dietary pattern and the risk of liver cancer. CONCLUSION: A vegetable-based dietary pattern in males and a fruit-based dietary pattern in females tended to have a protective role on liver cancer risk. This study provided updated information that might be applied to guide public health action for the primary prevention of liver cancer.


Assuntos
Dieta , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/epidemiologia , Feminino , Masculino , China/epidemiologia , Pessoa de Meia-Idade , Dieta/estatística & dados numéricos , Dieta/métodos , Incidência , Estudos de Coortes , Fatores Sexuais , Fatores de Risco , Adulto , Seguimentos , Idoso , Modelos de Riscos Proporcionais , Estudos Prospectivos , Comportamento Alimentar , Verduras , Padrões Dietéticos
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