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1.
Chem Soc Rev ; 53(4): 2056-2098, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38214051

RESUMEN

Global warming has become a growing concern over decades, prompting numerous research endeavours to reduce the carbon dioxide (CO2) emission, the major greenhouse gas (GHG). However, the contribution of other non-CO2 GHGs including methane (CH4), nitrous oxide (N2O), fluorocarbons, perfluorinated gases, etc. should not be overlooked, due to their high global warming potential and environmental hazards. In order to reduce the emission of non-CO2 GHGs, advanced separation technologies with high efficiency and low energy consumption such as adsorptive separation or membrane separation are highly desirable. Advanced porous materials (APMs) including metal-organic frameworks (MOFs), covalent organic frameworks (COFs), hydrogen-bonded organic frameworks (HOFs), porous organic polymers (POPs), etc. have been developed to boost the adsorptive and membrane separation, due to their tunable pore structure and surface functionality. This review summarizes the progress of APM adsorbents and membranes for non-CO2 GHG separation. The material design and fabrication strategies, along with the molecular-level separation mechanisms are discussed. Besides, the state-of-the-art separation performance and challenges of various APM materials towards each type of non-CO2 GHG are analyzed, offering insightful guidance for future research. Moreover, practical industrial challenges and opportunities from the aspect of engineering are also discussed, to facilitate the industrial implementation of APMs for non-CO2 GHG separation.

2.
Int J Cancer ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874435

RESUMEN

Multiple myeloma (MM) is a heterogeneous disease with a small subset of high-risk patients having poor prognoses. Identifying these patients is crucial for treatment management and strategic decisions. In this study, we developed a novel computational framework to define prognostic gene signatures by selecting genes with expression driven by clonal copy number alterations. We applied this framework to MM and developed a clonal gene signature (CGS) consisting of 22 genes and evaluated in five independent datasets. The CGS provided significant prognostic values after adjusting for well-established factors including cytogenetic abnormalities, International Staging System (ISS), and Revised ISS (R-ISS). Importantly, CGS demonstrated higher performance in identifying high-risk patients compared to the GEP70 and SKY92 signatures recommended for prognostic stratification of MM. CGS can further stratify patients into subgroups with significantly differential prognoses when applied to the high- and low-risk groups identified by GEP70 and SKY92. Additionally, CGS scores are significantly associated with patient response to dexamethasone, a commonly used treatment for MM. In summary, we proposed a computational framework that requires only gene expression data to identify CGSs for prognosis prediction. CGS provides a useful biomarker for improving prognostic stratification in MM, especially for identifying the highest-risk patients.

3.
Inorg Chem ; 63(25): 11860-11869, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38861347

RESUMEN

The newly reported crystalline phosphorus nanosheets (cryst-P NSs) exhibit promising features for industrial applications, including outstanding air-water stability and facile large-scale production. However, their complex crystallization impedes a priori tailoring. Herein, the temporal evolution of cryst-P NSs was investigated with the optimized synthesis parameters. The occurrence of self-assembly and solid-state rearrangement unveiled the existence of an intermediate phase as the bulk crystalline precursor and the predominance of nonclassical crystallization pathway(s). With the upgraded synthesis protocol simultaneously strengthening the merits of cryst-P NSs, their catalytic performances were evaluated in various electro- and/or photocatalytic reactions spanning hydrogen and oxygen evolution, full water splitting, CO2 reduction, and organic pollutant decomposition. Superior catalytic activities and orders of magnitude longer lifetimes were consistently discerned compared with the widely employed black phosphorus nanosheets with similar size and thickness. The exciting discoveries in both fundamental crystallization and catalytic applications drastically thrust the comprehension of elemental phosphorus, shedding light on the encouraging capabilities of solvothermal synthesis strategies in the design and systematic tailoring of phosphorus materials.

4.
Inorg Chem ; 63(16): 7412-7421, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38600810

RESUMEN

Nonplanar porphyrins play crucial roles in many biological processes and chemical reactions as catalysts. However, the preparation of artificial nonplanar porphyrins suffers from complicated organic syntheses. Herein, we present a new rare-earth porphyrinic metal-organic framework (RE-PMOF), BUT-233, which is a three-dimensional (3D) framework structure with the flu topology consisting of 4-connected BBCPPP-Ph ligands H4BBCPPP-Ph = 5',5⁗-(10,20-diphenylporphyrin-5,15-diyl)bis([1,1':3',1″-terphenyl]-4,4'' dicarboxylic acid) and 8-connected Eu6 clusters. Noteworthily, the porphyrin cores of the BBCPPP-Ph ligands in BUT-233 are nonplanar with a ruffle-like conformation. In contrast, the porphyrin core in the free ligand H4BBCPPP-Ph is in a nearly ideally planar conformation, as confirmed by its single-crystal structure. BUT-233 is microporous with 6-8 Špores and a Brunauer-Emmett-Teller (BET) surface area of 649 m2/g, as well as high stability in common solvents. The MOF was used as a photocatalyst for the oxidation degradation of a chemical warfare agent model molecule CEES (CEES = 2-chloroethyl ethyl sulfide) under the light-emitting diode (LED) irradiation and an O2 atmosphere at room temperature. CEES was almost completely converted into its nontoxic light-oxidized product CEESO (CEESO = 2-chloroethyl ethyl sulfoxide) in only 5 min with t1/2 = 2 min (t1/2: half-life). Moreover, the toxic deep-oxidized product 2-chloroethyl ethyl sulfone (CEESO2) was not detected. The catalytic activity of BUT-233 was high in comparison with those of some previously reported MOF catalysts. The results of photo/electrochemical property studies suggested that the high catalytic activity of BUT-233 was benefited from the presence of nonplanar porphyrin rings on its pore surface.

5.
Inorg Chem ; 63(9): 4249-4259, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38364203

RESUMEN

The emission of volatile organic compounds (VOCs) significantly contributes to air pollution and poses a serious threat to human health. Benzene, one of the most toxic VOCs, is difficult for the human body to metabolize and is classified as a Group 1 carcinogen. The development of efficient adsorbents for removing trace amounts of benzene from ambient air is thus of great importance. In this work, we studied the benzene adsorption properties of four Zr-based metal-organic frameworks (Zr-MOFs) through static volumetric and dynamic breakthrough experiments. Two previously reported Zr-MOFs, BUT-12 and STA-26, were prepared with a tritopic carboxylic acid ligand (H3L1) functionalized with three methyl groups, and STA-26 is a 2-fold interpenetrated network of BUT-12. Two new isoreticular Zr-MOFs, BUT-12-Et and STA-26-Et, were synthesized using a similar ligand, H3L2, where the methyl groups are replaced with ethyl groups. There are mesopores in BUT-12 and BUT-12-Et and micropores in STA-26 and STA-26-Et. The four Zr-MOFs all showed high stability in liquid water and acidic aqueous solutions. The microporous STA-26 and STA-26-Et showed much higher benzene uptakes than mesoporous BUT-12 and BUT-12-Et at room temperature under low pressures. Particularly, the benzene adsorption capacity of STA-26-Et was high up to 2.21 mmol/g at P/P0 = 0.001 (P0 = 12.78 kPa), higher than those of the other three Zr-MOFs and most reported solid adsorbents. Breakthrough experiments confirmed that STA-26-Et could effectively capture trace benzene (10 ppm) from dry air; however, its benzene capture capacity was reduced by 90% under humid conditions (RH = 50%). Coating of the crystals of STA-26-Et with polydimethylsiloxane (PDMS) increased the hydrophobicity of the exterior MOF surfaces, leading to a more than 2-fold improvement in its benzene capture capacity in the breakthrough experiment under humid condition. PDMS coating of STA-26-Et likely slowed down the water adsorption process, and thus, the adsorbent afforded more efficient capture of benzene. This work demonstrates that modifying both the interior and exterior surfaces of MOFs can effectively enhance their performance in capturing trace benzene from ambient air, even under humid conditions. This finding is meaningful for the development of new adsorbents for effective air purification applications.

6.
Inorg Chem ; 63(23): 10817-10822, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38781577

RESUMEN

A K-Eu bimetallic ammonium metal-nitrate three-dimensional (3D) framework incorporating R-N-methyl-3-hydroxyquinuclidine, (RM3HQ)2KEu(NO3)6 (RM3HQ = R-N-methyl-3-hydroxyquinuclidine, 1), was characterized and reported. Distinguishing from the former hybrid rare-earth double perovskites, 1 adopts a mixed corner- and face-sharing K+/Eu3+-centered polyhedral connectivity to form a 3D inorganic framework, showing a rare (6, 6)-connected ion topology with a 66 framework. Notably, 1 exhibits clear phase transition, and the switchable thermodynamic behavior is confirmed by variable-temperature dielectric measurements and second-harmonic generation response. Moreover, 1 also shows photoluminescence properties. The activator Eu3+ plays a crucial role in this process, leading to a significant narrow emission at 592 nm with a photoluminescence quantum yield (PLQY) of 20.76%. The fluorescence lifetime (FLT) of 1 is 4.32 ms. This finding enriches the bimetallic hybrid system for potential electronic and/or luminescence applications.

7.
Inorg Chem ; 63(15): 6972-6979, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38567571

RESUMEN

Single-crystal membranes (SCMs) show great promise in the fields of sensors, light-emitting diodes, and photodetection. However, the growth of a large-area single-crystal membranes is challenging. We report a new organic-inorganic SCMs [HCMA]2CuBr4 (HCMA = cyclohexanemethylamine) crystallized at the gas-liquid interface. It also has low-temperature ferromagnetic order, high-temperature dielectric anomalies, and narrow band gap indirect semiconductor properties. Specifically, the reversible phase transition of the compound occurs at 350/341 K on cooling/heating and exhibits dielectric anomalies and stable switching performance near the phase transition temperature. The ferromagnetic exchange interaction in the inorganic octahedra and the organic layer enables ferromagnetic ordering at low-temperature 10 K. Finally, the single crystal exhibits an indirect semiconducting property with a narrow band gap of 0.99 eV. Such rich multichannel physical properties make it a potential application in photodetection, information storage and sensors.

8.
J Chem Inf Model ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38529913

RESUMEN

Along with the development of machine learning, deep learning, and large language models (LLMs) such as GPT-4 (GPT: Generative Pre-Trained Transformer), artificial intelligence (AI) tools have been playing an increasingly important role in chemical and material research to facilitate the material screening and design. Despite the exciting progress of GPT-4 based AI research assistance, open-source LLMs have not gained much attention from the scientific community. This work primarily focused on metal-organic frameworks (MOFs) as a subdomain of chemistry and evaluated six top-rated open-source LLMs with a comprehensive set of tasks including MOFs knowledge, basic chemistry knowledge, in-depth chemistry knowledge, knowledge extraction, database reading, predicting material property, experiment design, computational scripts generation, guiding experiment, data analysis, and paper polishing, which covers the basic units of MOFs research. In general, these LLMs were capable of most of the tasks. Especially, Llama2-7B and ChatGLM2-6B were found to perform particularly well with moderate computational resources. Additionally, the performance of different parameter versions of the same model was compared, which revealed the superior performance of higher parameter versions.

9.
Nat Mater ; 21(6): 689-695, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35484330

RESUMEN

In principle, porous physisorbents are attractive candidates for the removal of volatile organic compounds such as benzene by virtue of their low energy for the capture and release of this pollutant. Unfortunately, many physisorbents exhibit weak sorbate-sorbent interactions, resulting in poor selectivity and low uptake when volatile organic compounds are present at trace concentrations. Herein, we report that a family of double-walled metal-dipyrazolate frameworks, BUT-53 to BUT-58, exhibit benzene uptakes at 298 K of 2.47-3.28 mmol g-1 at <10 Pa. Breakthrough experiments revealed that BUT-55, a supramolecular isomer of the metal-organic framework Co(BDP) (H2BDP = 1,4-di(1H-pyrazol-4-yl)benzene), captures trace levels of benzene, producing an air stream with benzene content below acceptable limits. Furthermore, BUT-55 can be regenerated with mild heating. Insight into the performance of BUT-55 comes from the crystal structure of the benzene-loaded phase (C6H6@BUT-55) and density functional theory calculations, which reveal that C-H···X interactions drive the tight binding of benzene. Our results demonstrate that BUT-55 is a recyclable physisorbent that exhibits high affinity and adsorption capacity towards benzene, making it a candidate for environmental remediation of benzene-contaminated gas mixtures.


Asunto(s)
Estructuras Metalorgánicas , Compuestos Orgánicos Volátiles , Adsorción , Benceno/química , Gases
10.
Inorg Chem ; 62(12): 4762-4769, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36529942

RESUMEN

The separation of ethane from ethylene is an important but challenging process in the chemical industry because of their similar physicochemical properties. Generally, the adsorbents for C2H6/C2H4 separation require an appropriate and relatively small aperture. Herein, we report two dynamic pillar-layered metal-organic frameworks (MOFs) BUT-111 and BUT-112 with isomorphic frameworks but different degrees of interpenetration for efficient C2H4 purification. The dynamic behavior makes both the activated MOFs exhibit ultramicropores and reversed order adsorption behavior for C2H6 and C2H4, which could obtain highly purified C2H4 in one step from the C2H6/C2H4 mixture. BUT-111 and BUT-112 could work in a wide temperature range, and with the decrease in temperature, the C2H6/C2H4 selectivity would increase. Moreover, the degree of interpenetration could be well controlled by the synthetic temperature, and the increase in the interpenetration degree of BUT-112 enhanced the C2H4 purification effectively.

11.
Inorg Chem ; 62(31): 12329-12336, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37478416

RESUMEN

Propyne/propylene separation is important in the petrochemical industry but challenging due to their similar physical properties and close molecular sizes. Metal-organic frameworks (MOFs) are a class of promising adsorbents for light hydrocarbon separations. Among them, the so-called "flexible-robust" MOFs combine the advantages of flexibility and rigidity in structure and could show enhanced gas separation selectivity as well as improved gas uptake at low pressure. Interpenetrated MOFs offer a platform to explore the "flexible-robust" feature of MOFs based on their subnetwork displacement in the process of gas adsorption. Herein, we present two hydrolytically stable MOFs (BUT-308 and BUT-309) with interpenetrated structures and fascinating propyne/propylene separation performance. BUT-308 is composed of interpenetrated 2D Cu(BDC-NH2)BPB layers (H2BDC-NH2 = 2-aminobenzene-1,4-dicarboxylic acid; BPB = 1,4-bis(4-pyridyl)benzene), while BUT-309 consists of twofold interpenetrated 3D pillared-layer Cu2(BDC-NH2)2(BPB-CF3) nets (BPB-CF3 = 2-trifluoromethyl-1,4-bis(4-pyridyl)benzene). Gas adsorption measurements showed that BUT-309 was a "flexible-robust" adsorbent with multistep adsorption isotherms for C3H4 rather than C3H6 at a wide temperature range. The guest-dependent pore-opening behavior endows BUT-309 with high potential in the C3H4/C3H6 separation. The C3H4 adsorption measurements of BUT-309 at 273-323 K showed that the lowering of the temperature induced the pore-opening action at lower pressure. Column breakthrough experiments further confirmed the capability of BUT-309 for the efficient removal of C3H4 from a C3H4/C3H6 binary gas, and the C3H6 processing capacity at 273 K (15.7 cm3 g-1) was higher than that at 298 K (35.2 cm3 g-1). This work shows a rare example of "flexible-robust" MOFs and demonstrated its high potential for C3H4/C3H6 separation.

12.
Environ Sci Technol ; 57(49): 20962-20973, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38008907

RESUMEN

As a generally existing component in industrial streams, H2O usually inhibits the catalytic degradation efficiency of volatile organic compounds (VOCs) greatly. Here, we propose a novel strategy that accelerates the H2O dissociation and facilitates positive feedbacks during VOC oxidation by fabricating citric acid (CA)-assisted Pt(K)-Mn2O3/SiO2 (Pt-Mn/KS-xCA). Results reveal that the complexation of carboxyl groups of citric acid with Mn cations leads to the formation of small Mn2O3 (4.1 ± 0.2 nm) and further enhances the Mn-O-Pt interaction (strengthened by the Si-O-Mn interaction), which can transfer more electrons from Pt-Mn/KS-6CA to H2O, thus facilitating its breaking of covalent bonds. It subsequently produces abundant surface hydroxyl groups, improving the adsorption and activation abilities of acetone reactant and ethanol intermediate. Attributing to these, the acetone turnover frequency value of Pt-Mn/KS-6CA is 1.8 times higher than that of Pt-Mn/KS at 160 °C, and this multiple changes to 6.3 times in the presence of H2O. Remarkably, acetone conversion over Pt-Mn/KS-6CA increases by up to 14% in the presence of H2O; but it decreases by up to 26% for Pt-Mn/KS due to its weak dissociation ability and high adsorption capacity toward H2O. This work sheds new insights into the design of highly efficient catalytic materials for VOC degradation under humid conditions.


Asunto(s)
Compuestos Orgánicos Volátiles , Agua , Agua/química , Acetona , Compuestos Orgánicos Volátiles/química , Dióxido de Silicio , Ácido Cítrico
13.
Chem Soc Rev ; 51(15): 6417-6441, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35702993

RESUMEN

Metal-organic frameworks (MOFs) are a new class of porous crystalline materials constructed from organic ligands and metal ions/clusters. Owing to their unique advantages, they have attracted more and more attention in recent years and numerous studies have revealed their great potential in various applications. Many important applications of MOFs inevitably involve harsh alkaline operational environments. To achieve high performance and long cycling life in these applications, high stability of MOFs against bases is necessary. Therefore, the construction of base-stable MOFs has become a critical research direction in the MOF field. This review gives a historic summary of the development of base-stable MOFs in the last few years. The key factors that can determine the robustness of MOFs under basic conditions are analyzed. We also demonstrate the exciting achievements that have been made by utilizing base-stable MOFs in different applications. In the end, we discuss major challenges for the further development of base-stable MOFs. Some possible methods to address these problems are presented.

14.
BMC Genomics ; 23(1): 196, 2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35272635

RESUMEN

BACKGROUND: Expression quantitative trait loci (eQTLs) analyses have been widely used to identify genetic variants associated with gene expression levels to understand what molecular mechanisms underlie genetic traits. The resultant eQTLs might affect the expression of associated genes through transcriptional or post-transcriptional regulation. In this study, we attempt to distinguish these two types of regulation by identifying genetic variants associated with mRNA stability of genes (stQTLs). RESULTS: Here, we presented a computational framework that takes advantage of recently developed methods to infer the mRNA stability of genes based on RNA-seq data and performed association analysis to identify stQTLs. Using the Genotype-Tissue Expression (GTEx) lung RNA-Seq data, we identified a total of 142,801 stQTLs for 3942 genes and 186,132 eQTLs for 4751 genes from 15,122,700 genetic variants for 13,476 genes on the autosomes, respectively. Interestingly, our results indicated that stQTLs were enriched in the CDS and 3'UTR regions, while eQTLs are enriched in the CDS, 3'UTR, 5'UTR, and upstream regions. We also found that stQTLs are more likely than eQTLs to overlap with RNA binding protein (RBP) and microRNA (miRNA) binding sites. Our analyses demonstrate that simultaneous identification of stQTLs and eQTLs can provide more mechanistic insight on the association between genetic variants and gene expression levels.


Asunto(s)
Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Regulación de la Expresión Génica , Pulmón , Estabilidad del ARN
15.
Acc Chem Res ; 54(15): 3083-3094, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34260201

RESUMEN

Metal-organic frameworks (MOFs) have been attracting tremendous attention owing to their great structural diversity and functional tunability. Despite numerous inherent merits and big progress in the fundamental research (synthesizing new compounds, discovering new structures, testing associated properties, etc.), poor chemical stability of most MOFs severely hinders their involvement in practical applications, which is the final goal for developing new materials. Therefore, constructing new stable MOFs or stabilizing extant labile MOFs is quite important. As with them, some "potential" applications would come true and a lot of new applications under harsh conditions can be explored. Efficient strategies are being pursued to solve the stability problem of MOFs and thereby achieve and expand their applications.In this Account, we summarize the research advance in the design and synthesis of chemically stable MOFs, particularly those stable in acidic, basic, and aqueous systems, as well as in the exploration of their applications in several expanding fields of environment, energy, and food safety, which have been dedicated in our lab over the past decade. The strategies for accessing stable MOFs can be classified into: (a) assembling high-valent metals (hard acid, such as Zr4+, Al3+) with carboxylate ligands (hard base) for acid-stable MOFs; (b) combining low-valent metals (soft acid, such as Co2+, Ni2+) and azolate ligands (soft base, such as pyrazolate) for alkali-resistant MOFs; (c) enhancing the connectivity of the building unit; (d) contracting or rigidifying the ligand; (e) increasing the hydrophobicity of the framework; and (f) substituting liable building units with stable ones (such as metal metathesis) to obtain robust MOFs. In addition, other factors, including the geometry and symmetry of building units, framework-framework interaction, and so forth, have also been taken into account in the design and synthesis of stable MOFs. On the basis of these approaches, the stability of resulting MOFs under corresponding conditions has been remarkably enhanced.With high chemical stability achieved, the MOFs have found many new and significant applications, aiming at addressing global challenges related to environmental pollution, energy shortage, and food safety.A series of stable MOFs have been constructed for detecting and eliminating contaminations. Various fluorescent MOFs were rationally customized to be powerful platforms for sensing hazardous targets in food and water, such as dioxins, antibiotics, veterinary drugs, and heavy metal ions. Some hydrophobic MOFs even showed effective and specific capture of low-concentration volatile organic compounds.Novel MOFs with record-breaking acid/base/nucleophilic regent resistance have expanded their application scope under harsh conditions. BUT-8(Cr)A, as the most acid-stable MOF yet, showed reserved structural integrity in concentrated H2SO4 and recorded high proton conductivity; the most alkali-resistant MOF, PCN-601, retained crystallinity even in boiling saturated NaOH aqueous solution, and such base-stable MOFs composed of non-noble metal clusters and poly pyrazolate ligands also demonstrated great potential in heterogeneous catalysis in alkaline/nucleophilic systems for the first time.It is believed that this Account will provide valuable references on stable MOFs' construction as well as application expansion toward harsh conditions, thereby being helpful to promote MOF materials to step from fundamental research to practical applications.

16.
Inorg Chem ; 61(20): 8015-8021, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35544341

RESUMEN

The rapid detection of antibiotics in agricultural products is of great significance. In this work, two stable fluorescent metal-organic frameworks (MOFs), BUT-178 and BUT-179, are synthesized and used to detect tetracycline antibiotics. Among them, BUT-179 exhibits better performance in the detection of different tetracycline antibiotics in water and eggs. The limits of detection of BUT-179 toward tetracycline, aureomycin, oxytetracycline, and doxycycline all reach the nanomolar level. Furthermore, the cycling tests confirm that BUT-179 can be easily recovered and repeatedly used without an obvious performance loss. This work demonstrates the excellent application potential of MOFs for food safety, especially the fluorescence detection of antibiotics in foods.


Asunto(s)
Compuestos Heterocíclicos , Estructuras Metalorgánicas , Antibacterianos/farmacología , Colorantes , Fluorescencia , Tetraciclina
17.
Inorg Chem ; 61(4): 1918-1927, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35044169

RESUMEN

Metal-organic frameworks (MOFs) provide an ideal platform for ion exchange due to their high porosity and structural designability; however, developing MOFs that have the essential characteristics for ion exchange remains a challenge. These crucial features include fast kinetics, selectivity, and stability. We present two anionic isomers, DGIST-2 (2D) and DGIST-3 (3D), comprising distinctly arranged 5-(1,8-naphthalimido)isophthalate ligands and In3+ cations. Interestingly, in protic solvents, DGIST-2 transforms into a hydrolytically stable crystalline phase, DGIST-2'. DGIST-2' and DGIST-3 exhibit rapid Cs+ adsorption kinetics, as well as high Cs+ affinity in the presence of competing cations. The mechanism for rapid and selective sorption is explored based on the results of single-crystal X-ray diffraction analysis of Cs+-incorporated DGIST-3. In Cs+-containing solutions, the loosely incorporated dimethylammonium countercation of the anionic framework is replaced by Cs+, which is held in the hydrophobic cavity by supramolecular ion-ion and cation-π interactions.

18.
Int J Mol Sci ; 23(1)2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35008908

RESUMEN

The major biological methyl donor, S-adenosylmethionine (adoMet) synthesis occurs mainly in the liver. Methionine adenosyltransferase 1A (MAT1A) and glycine N-methyltransferase (GNMT) are two key enzymes involved in the functional implications of that variation. We collected 42 RNA-seq data from paired hepatocellular carcinoma (HCC) and its adjacent normal liver tissue from the Cancer Genome Atlas (TCGA). There was no mutation found in MAT1A or GNMT RNA in the 42 HCC patients. The 11,799 genes were annotated in the RNA-Seq data, and their expression levels were used to investigate the phenotypes of low MAT1A and low GNMT by Gene Set Enrichment Analysis (GSEA). The REACTOME_TRANSLATION gene set was enriched and visualized in a heatmap along with corresponding differences in gene expression between low MAT1A versus high MAT1A and low GNMT versus high GNMT. We identified 43 genes of the REACTOME_TRANSLATION gene set that are powerful prognosis factors in HCC. The significantly predicted genes were referred into eukaryotic translation initiation (EIF3B, EIF3K), eukaryotic translation elongation (EEF1D), and ribosomal proteins (RPs). Cell models expressing various MAT1A and GNMT proved that simultaneous restoring the expression of MAT1A and GNMT decreased cell proliferation, invasion, as well as the REACTOME_TRANSLATION gene EEF1D, consistent with a better prognosis in human HCC. We demonstrated new findings that downregulation or defect in MAT1A and GNMT genes can enrich the protein-associated translation process that may account for poor HCC prognosis. This is the first study demonstrated that MAT1A and GNMT, the 2 key enzymes involved in methionine cycle, could attenuate the function of ribosome translation. We propose a potential novel mechanism by which the diminished GNMT and MAT1A expression may confer poor prognosis for HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica , Glicina N-Metiltransferasa/genética , Neoplasias Hepáticas/genética , Metionina Adenosiltransferasa/genética , Metionina/metabolismo , Biosíntesis de Proteínas , Secuencia de Bases , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/genética , Metilación de ADN/genética , Factor 3 de Iniciación Eucariótica/metabolismo , Glicina N-Metiltransferasa/metabolismo , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/patología , Metionina Adenosiltransferasa/metabolismo , Invasividad Neoplásica , Factor 1 de Elongación Peptídica/metabolismo , Regiones Promotoras Genéticas/genética , Biosíntesis de Proteínas/genética , Análisis de Supervivencia
19.
J Am Chem Soc ; 143(26): 9901-9911, 2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34167295

RESUMEN

Constructing stable palladium(II)-based metal-organic frameworks (MOFs) would unlock more opportunities for MOF chemistry, particularly toward applications in catalysis. However, their availability is limited by synthetic challenges due to the inertness of the Pd-ligand coordination bond, as well as the strong tendency of the Pd(II) source to be reduced under typical solvothermal conditions. Under the guidance of reticular chemistry, herein, we present the first example of an azolate Pd-MOF, BUT-33(Pd), obtained via a deuterated solvent-assisted metal metathesis. BUT-33(Pd) retains the underlying sodalite network and mesoporosity of the template BUT-33(Ni) and shows excellent chemical stability (resistance to an 8 M NaOH aqueous solution). With rich Pd(II) sites in the atomically precise distribution, it also demonstrates good performances as a heterogeneous Pd(II) catalyst in a wide application scope, including Suzuki/Heck coupling reactions and photocatalytic CO2 reduction to CH4. This work highlights a feasible approach to reticularly construct noble metal based MOFs via metal metathesis, in which various merits, including high chemical stability, large pores, and tunable functions, have been integrated for addressing challenging tasks.

20.
J Am Chem Soc ; 143(7): 2784-2791, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33492147

RESUMEN

The exploration of metal-organic frameworks (MOFs) through the rational design of building units with specific sizes, geometries, and symmetries is essential for enriching the structural diversity of porous solids for applications including storage, separation, and conversion. However, it is still a challenge to directly synthesize rare-earth (RE) MOFs with less connected clusters as a thermodynamically favored product. Herein, we report a systematic investigation on the influence of size, rigidity, and symmetry of linkers over the formation of RE-tetracarboxylate MOFs and uncover the critical role of linker desymmetrization in constructing RE-MOFs with eight-connected hexanuclear clusters. Our results on nine new RE-MOFs, PCN-50X (X = 1-9), indicate that utilization of trapezoidal or tetrahedral linkers provides accesses to traditionally unattainable RE-tetracarboxylate MOFs with 8-c hexanuclear nodes, while the introduction of square or rectangular linkers during the assembly of RE-MOFs based on polynuclear clusters typically leads to the MOFs constructed from 12-c nodes with underlying shp topology. By rational linker design, MOFs with two unprecedented (4, 8)-c nets, lxl and jun, can also be obtained. This work highlights linker desymmetrization as a powerful strategy to enhance MOFs' structural complexity and access MOF materials with nondefault topologies that can be potentially used for separation and catalysis.

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