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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38555477

RESUMO

Coronavirus disease 2019 (COVID-19) has been wreaking havoc for 3 years. PANoptosis, a distinct and physiologically relevant inflammatory programmed cell death, perpetuates cytokine storm and multi-organ injuries in COVID-19. Although PANoptosis performs indispensable roles in host defense, further investigation is needed to elucidate the exact processes through which PANoptosis modulates immunological responses and prognosis in COVID-19. This study conducted a bioinformatics analysis of online single-cell RNA sequence (scRNA-seq) and bulk RNA-seq datasets to explore the potential of PANoptosis as an indicator of COVID-19 severity. The degree of PANoptosis in bronchoalveolar lavage fluid (BALF) and peripheral blood mononuclear cells (PBMC) indicated the severity of COVID-19. Single-cell transcriptomics identified pro-inflammatory monocytes as one of the primary sites of PANoptosis in COVID-19. The study subsequently demonstrated the immune and metabolic characteristics of this group of pro-inflammatory monocytes. In addition, the analysis illustrated that dexamethasone was likely to alleviate inflammation in COVID-19 by mitigating PANoptosis. Finally, the study showed that the PANoptosis-related genes could predict the intensive care unit admission (ICU) and outcomes of COVID-19 patients who are hospitalized.


Assuntos
COVID-19 , Humanos , COVID-19/genética , Leucócitos Mononucleares , Biologia Computacional , Perfilação da Expressão Gênica , Hospitalização
2.
J Am Chem Soc ; 146(6): 4153-4161, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38300827

RESUMO

Separating ethane (C2H6) from ethylene (C2H4) is an essential and energy-intensive process in the chemical industry. Here, we report two flexible diamondoid coordination networks, X-dia-1-Ni and X-dia-1-Ni0.89Co0.11, that exhibit gate-opening between narrow-pore (NP) and large-pore (LP) phases for C2H6, but not for C2H4. X-dia-1-Ni0.89Co0.11 thereby exhibited a type F-IV isotherm at 273 K with no C2H6 uptake and a high uptake (111 cm3 g-1, 1 atm) for the NP and LP phases, respectively. Conversely, the LP phase exhibited a low uptake of C2H4 (12.2 cm3 g-1). This C2H6/C2H4 uptake ratio of 9.1 for X-dia-1-Ni0.89Co0.11 far surpassed those of previously reported physisorbents, many of which are C2H4-selective. In situ variable-pressure X-ray diffraction and modeling studies provided insight into the abrupt C2H6-induced structural NP to LP transformation. The promise of pure gas isotherms and, more generally, flexible coordination networks for gas separations was validated by dynamic breakthrough studies, which afforded high-purity (99.9%) C2H4 in one step.

3.
Small ; 20(23): e2308005, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38148319

RESUMO

The conversion of CO2 into valuable carbon-based products using clean and renewable solar energy has been a significant challenge in photocatalysis. It is of paramount importance to develop efficient photocatalysts for the catalytic conversion of CO2 using visible light. In this study, the Ni-MOF-74 material is successfully modified to achieve a highly porous structure (Ni-74-Am) through temperature and solvent modulation. Compared to the original Ni-MOF-74, Ni-74-Am contains more unsaturated Ni active sites resulting from defects, thereby enhancing the performance of CO2 photocatalytic conversion. Remarkably, Ni-74-Am exhibits outstanding photocatalytic performance, with a CO generation rate of 1380 µmol g-1 h-1 and 94% CO selectivity under visible light, significantly surpassing the majority of MOF-based photocatalysts reported to date. Furthermore, experimental characterizations reveal that Ni-74-Am has significantly higher efficiency of photogenerated electron-hole separation and faster carrier migration rate for photocatalytic CO2 reduction. This work enriches the design and application of defective MOFs and provides new insights into the design of MOF-based photocatalysts for renewable energy and environmental sustainability. The findings of this study hold significant promise for developing efficient photocatalysts for CO2 reduction under visible-light conditions.

4.
Small ; : e2402523, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747010

RESUMO

A 44.610.8 topology hybrid ultramicroporous material (HUM), {[Cu1.5F(SiF6)(L)2.5]·G}n, (L = 4,4'-bisimidazolylbiphenyl, G = guest molecules), 1, formed by cross-linking interpenetrated 3D four-connected CdSO4-type nets with hexafluorosilicate anions is synthesized and evaluated in the context of gas sorption and separation herein. 1 is the first HUM functionalized with two different types of fluorinated sites (SiF6 2- and F- anions) lining along the pore surface. The optimal pore size (≈5 Å) combining mixed and high-density electronegative fluorinated sites enable 1 to preferentially adsorb C2H2 over CO2 and C2H4 by hydrogen bonding interactions with a high C2H2 isosteric heat of adsorption (Qst) of ≈42.3 kJ mol-1 at zero loading. The pronounced discriminatory sorption behaviors lead to excellent separation performance for C2H2/CO2 and C2H2/C2H4 that surpasses many well-known sorbents. Dynamic breakthrough experiments are conducted to confirm the practical separation capability of 1, which reveal an impressive separation factor of 6.1 for equimolar C2H2/CO2 mixture. Furthermore, molecular simulation and density functional theory (DFT) calculations validate the strong binding of C2H2 stems from the chelating fix of C2H2 between SiF6 2- anion and coordinated F- anion.

5.
Arterioscler Thromb Vasc Biol ; 43(6): 910-926, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37078289

RESUMO

BACKGROUND: The benefits of exercise on the cardiovascular system are widely recognized; however, the underlying mechanisms are unknown. Here, we report the effect of the long noncoding RNA NEAT1 (nuclear paraspeckle assembly transcript 1), which is regulated by exercise, on atherosclerosis development after N6-methyladenosine (m6A) modifications. METHODS: Using clinical cohorts and NEAT1-/- mice, we determined the exercise-mediated expression and role of NEAT1 in atherosclerosis. To investigate the mechanism of epigenetic modification of NEAT1 regulated by exercise, we identified METTL14 (methyltransferase-like 14)-a key m6A modification enzyme under exercise-and found that METTL14 alters the expression and role of NEAT1 through m6A modification and elucidated the specific mechanism of METTL14 in vitro and in vivo. Finally, the NEAT1 downstream regulatory network was investigated. RESULTS: We found that NEAT1 expression was downregulated with exercise and that downregulation of NEAT1 was an important factor in the improvement of atherosclerosis with exercise. Exercise-mediated loss of function of NEAT1 can delay atherosclerosis. Mechanistically, we showed that exercise induced a significant downregulation of m6A modification and METTL14, which binds to the m6A sites of NEAT1 and promotes NEAT1 expression through subsequent YTHDC1 (YTH domain-containing 1) recognition to promote endothelial pyroptosis. Furthermore, NEAT1 induces endothelial pyroptosis by binding KLF4 (Kruppel-like factor 4) to promote the transcriptional activation of the key pyroptotic protein NLRP3 (NOD-like receptor thermal protein domain-associated protein 3), whereas exercise can attenuate NEAT1-mediated endothelial pyroptosis to improve atherosclerosis. CONCLUSIONS: Our study of NEAT1 provides new insights into the improvement of atherosclerosis by exercise. This finding demonstrates the role of exercise-mediated NEAT1 downregulation in atherosclerosis while expanding our understanding of the mechanisms by which exercise regulates long noncoding RNA function through epigenetic modifications.


Assuntos
Aterosclerose , RNA Longo não Codificante , Animais , Camundongos , Adenosina , Aterosclerose/genética , Aterosclerose/prevenção & controle , Piroptose , RNA Longo não Codificante/genética
6.
Nano Lett ; 23(18): 8585-8592, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37669044

RESUMO

Single-atom nanozymes (SAzymes) open new possibilities for the development of artificial enzymes that have catalytic activity comparable to that of natural peroxidase (POD). So far, most efforts have focused on the structural modulation of the Fe-N4 moiety to mimic the metalloprotein heme center. However, non-heme-iron POD with much higher activity, for example, HppE, has not been mimicked successfully due to its structural complexity. Herein, carbon dots (CDs)-supported SAzymes with twisted, nonplanar Fe-O3N2 active sites, highly similar to the non-heme iron center of HppE, was synthesized by exploiting disordered and subnanoscale domains in CDs. The Fe-CDs exhibit an excellent POD activity of 750 units/mg, surpassing the values of conventional SAzymes with planar Fe-N4. We further fabricated an activatable Fe-CDs-based therapeutic agent with near-infrared enhanced POD activity, a photothermal effect, and tumor-targeting ability. Our results represent a big step in the design of high-performance SAzymes and provide guidance for future applications for synergistic tumor therapy.

7.
Molecules ; 29(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38930967

RESUMO

The integration of two-dimensional Ti3C2Tx nanosheets and other materials offers broader application options in the antibacterial field. Ti3C2Tx-based composites demonstrate synergistic physical, chemical, and photodynamic antibacterial activity. In this review, we aim to explore the potential of Ti3C2Tx-based composites in the fabrication of an antibiotic-free antibacterial agent with a focus on their systematic classification, manufacturing technology, and application potential. We investigate various components of Ti3C2Tx-based composites, such as metals, metal oxides, metal sulfides, organic frameworks, photosensitizers, etc. We also summarize the fabrication techniques used for preparing Ti3C2Tx-based composites, including solution mixing, chemical synthesis, layer-by-layer self-assembly, electrostatic assembly, and three-dimensional (3D) printing. The most recent developments in antibacterial application are also thoroughly discussed, with special attention to the medical, water treatment, food preservation, flexible textile, and industrial sectors. Ultimately, the future directions and opportunities are delineated, underscoring the focus of further research, such as elucidating microscopic mechanisms, achieving a balance between biocompatibility and antibacterial efficiency, and investigating effective, eco-friendly synthesis techniques combined with intelligent technology. A survey of the literature provides a comprehensive overview of the state-of-the-art developments in Ti3C2Tx-based composites and their potential applications in various fields. This comprehensive review covers the variety, preparation methods, and applications of Ti3C2Tx-based composites, drawing upon a total of 171 English-language references. Notably, 155 of these references are from the past five years, indicating significant recent progress and interest in this research area.


Assuntos
Antibacterianos , Titânio , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Titânio/química , Titânio/farmacologia , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
8.
Lab Invest ; 103(12): 100263, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37839637

RESUMO

In this study, we aimed to explore immune markers predicting locoregional recurrence/distant metastasis (R/M) for patients with esophageal squamous cell carcinoma (ESCC) post-surgical intervention by using a novel high-throughput spatial tool to quantify multiple immune proteins expressed in ESCC and lymphocytes in tumor microenvironment (TME-L). First, formalin-fixed paraffin-embedded tissues from surgical patients with ESCC (n = 94) were constructed on a microarray, which was then divided into discovery (n = 36) and validation cohorts (n = 58). Using a newly developed GeoMx digital spatial profiling tool, 31 immune proteins in paired ESCC and TME-L, morphologically segmented by PANCK and CD45, respectively, from the discovery cohort were quantified, releasing 2,232 variables. Next, the correlation matrix was analyzed using the Corrplot package in R Studio, resulting in 6 closely correlated clusters. The Least Absolute Shrinkage and Selection Operator regression scoring model predictive of R/M risk with superior specificity was successfully established based on the 3 following hierarchically clustered immune proteins: ARG1 in ESCC/PANCK+, STING, and IDO1 in TME-L/CD45+. Moreover, the expression of IDO1 in TME-L, rather than in ESCC, significantly predicted the R/M risk score with an area under curve of 0.9598. In addition, its correlation with R/M status was further validated by dual immunohistochemistry staining of IDO1 and CD45 in discovery and validation cohorts. Above all, our findings not only provide a more accurate scoring approach based on quantitative immune proteins for the prediction of R/M risk, but also propose that IDO1 in TME-L potentially plays a driving role in mediating R/M in ESCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Biomarcadores Tumorais , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Prognóstico , Microambiente Tumoral
9.
Small ; 19(38): e2302975, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194973

RESUMO

Considering the significant application of acetylene (C2 H2 ) in the manufacturing and petrochemical industries, the selective capture of impurity carbon dioxide (CO2 ) is a crucial task and an enduring challenge. Here, a flexible metal-organic framework (Zn-DPNA) accompanied by a conformation change of the Me2 NH2 + ions in the framework is reported. The solvate-free framework provides a stepped adsorption isotherm and large hysteresis for C2 H2 , but type-I adsorption for CO2 . Owing to their uptakes difference before gate-opening pressure, Zn-DPNA demonstrated favorable inverse CO2 /C2 H2 separation. According to molecular simulation, the higher adsorption enthalpy of CO2 (43.1 kJ mol-1 ) is due to strong electrostatic interactions with Me2 NH2 + ions, which lock the hydrogen-bond network and narrow pores. Furthermore, the density contours and electrostatic potential verifies the middle of the cage in the large pore favors C2 H2 and repels CO2 , leading to the expansion of the narrow pore and further diffusion of C2 H2 . These results provide a new strategy that optimizes the desired dynamic behavior for one-step purification of C2 H2 .

10.
J Korean Med Sci ; 38(8): e55, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36852851

RESUMO

BACKGROUND: The emergence of the severe acute respiratory syndrome coronavirus 2 omicron variant has been triggering the new wave of coronavirus disease 2019 (COVID-19) globally. However, the risk factors and outcomes for radiological abnormalities in the early convalescent stage (1 month after diagnosis) of omicron infected patients are still unknown. METHODS: Patients were retrospectively enrolled if they were admitted to the hospital due to COVID-19. The chest computed tomography (CT) images and clinical data obtained at baseline (at the time of the first CT image that showed abnormalities after diagnosis) and 1 month after diagnosis were longitudinally analyzed. Uni-/multi-variable logistic regression tests were performed to explore independent risk factors for radiological abnormalities at baseline and residual pulmonary abnormalities after 1 month. RESULTS: We assessed 316 COVID-19 patients, including 47% with radiological abnormalities at baseline and 23% with residual pulmonary abnormalities at 1-month follow-up. In a multivariate regression analysis, age ≥ 50 years, body mass index ≥ 23.87, days after vaccination ≥ 81 days, lymphocyte count ≤ 1.21 × 10-9/L, interleukin-6 (IL-6) ≥ 10.05 pg/mL and IgG ≤ 14.140 S/CO were independent risk factors for CT abnormalities at baseline. The age ≥ 47 years, presence of interlobular septal thickening and IL-6 ≥ 5.85 pg/mL were the independent risk factors for residual pulmonary abnormalities at 1-month follow-up. For residual abnormalities group, the patients with less consolidations and more parenchymal bands at baseline could progress on CT score after 1 month. There were no significant changes in the number of involved lung lobes and total CT score during the early convalescent stage. CONCLUSION: The higher IL-6 level was a common independent risk factor for CT abnormalities at baseline and residual pulmonary abnormalities at 1-month follow-up. There were no obvious radiographic changes during the early convalescent stage in patients with residual pulmonary abnormalities.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pessoa de Meia-Idade , Seguimentos , Estudos Retrospectivos , Convalescença , Interleucina-6
11.
Alzheimers Dement ; 19(8): 3679-3687, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36856072

RESUMO

INTRODUCTION: Current randomized trial evidence on the effect of physical activity (PA) intervention on cognitive function is scarce and mainly found in well-educated populations, limiting its generalizability. Furthermore, the modification effect of education levels remains understudied. We conducted a cluster randomized trial to evaluate the effects of PA intervention on cognitive function in a general older population, and whether education modifies such effects. METHODS: Eight villages were randomized to the intervention (four villages, n = 240) or the control (four villages, n = 271). The intervention group received an 8-week multilevel PA intervention based on a socio-ecological model, while the control did not. The intervention has been condensed to three levels with activities occurring at the individual (telephone counseling, printed material, and training sessions), interpersonal (peer group), and community levels (group sharing and coaching). The primary outcome was changes in global cognition (overall cognitive function) measured by the Telephone Interview for Cognitive Status (TICS-10) at 12-month follow-up. Repeated measurements were modeled using the linear mixed model, which assumed that the missing values were missing at random. RESULTS: The mean age was 70.94 years (standard deviation 5.71) and 55.6% were women. Compared to the control, the orientation improved from baseline at 12-month follow-up (0.24 points [95% confidence interval (CI), 0.03 to 0.46 points; P = 0.03]). Stratified analysis showed that the global cognition and orientation improved at 12-month follow-up among illiterate participants in the intervention (for global cognition, mean difference, 0.57 points [95% CI, 0.03 to 1.10], P = 0.04; for orientation, mean difference, 0.31 points [95% CI, 0.04 to 0.58], P = 0.03). DISCUSSION: These results confirm the improvements in orientation in older adults, as well as in global cognition and orientation in the illiterate at 12-month follow-up.


Assuntos
Cognição , Exercício Físico , Humanos , Feminino , Idoso , Masculino , Escolaridade , China
12.
Angew Chem Int Ed Engl ; 62(47): e202309985, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37770385

RESUMO

We report that linker ligand substitution involving just one atom induces a shape-memory effect in a flexible coordination network. Specifically, whereas SIFSIX-23-Cu, [Cu(SiF6 )(L)2 ]n , (L=1,4-bis(1-imidazolyl)benzene, SiF6 2- =SIFSIX) has been previously reported to exhibit reversible switching between closed and open phases, the activated phase of SIFSIX-23-CuN , [Cu(SiF6 )(LN )2 ]n (LN =2,5-bis(1-imidazolyl)pyridine), transformed to a kinetically stable porous phase with strong affinity for CO2 . As-synthesized SIFSIX-23-CuN , α, transformed to less open, γ, and closed, ß, phases during activation. ß did not adsorb N2 (77 K), rather it reverted to α induced by CO2 at 195, 273 and 298 K. CO2 desorption resulted in α', a shape-memory phase which subsequently exhibited type-I isotherms for N2 (77 K) and CO2 as well as strong performance for separation of CO2 /N2 (15/85) at 298 K and 1 bar driven by strong binding (Qst =45-51 kJ/mol) and excellent CO2 /N2 selectivity (up to 700). Interestingly, α' reverted to ß after re-solvation/desolvation. Molecular simulations and density functional theory (DFT) calculations provide insight into the properties of SIFSIX-23-CuN .

13.
J Phys Chem A ; 126(45): 8476-8486, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36343215

RESUMO

A combination of high-throughput molecular simulation and machine learning (ML) algorithms has been widely adopted to seek promising metal-organic frameworks (MOFs) as energy gas carriers. However, the currently reported studies are mainly limited to extracting top performers from existing databases, not fully unleashing the ML capabilities for intelligently predicting novel structures with better performance. Herein, an efficient self-evolutionary methodology was proposed for searching high-performance MOFs that are unstructured in the origin database, in which a Tangent Adaptive Genetic Algorithm (TAGA) was newly put forward for structural evolution and the high-precision ML model of eXtreme Gradient Boosting (XGBoost) was employed as the fitness function. By taking CH4 storage in MOFs at room temperature as a showcase and using the database of 51,163 hMOFs, the TAGA-XGBoost coupling strategy rapidly suggested a certain number of possible combinations of the building blocks to form new structures with gravimetric storage capacity (35 bar) and volumetric working capacity (65-5.8 bar) higher than the best materials in the original database. The structures of some promising MOFs successfully used the finally optimized material genes for the two application conditions, and their performances were also confirmed by subsequent molecular simulations. The best materials can respectively reach a storage amount of 580 cm3(STP)/g at 35 bar and a working capacity of 218 cm3(STP)/cm3 between 65 and 5.8 bar. An analysis of the top 100 materials predicted from our method revealed that the choice of organic linkers has a systematic effect on the storage performance of MOFs. It might be believed that the proposed methodology offers an opportunity to expedite the discovery of unprecedented materials for other practical applications.


Assuntos
Estruturas Metalorgânicas , Simulação por Computador , Algoritmos , Aprendizado de Máquina
14.
J Fish Biol ; 101(1): 289-301, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35633144

RESUMO

This study examines the adaptability of a Southern Ocean predator, which is dependent on Antarctic krill (Euphausia superba), to potential changes in food availability. Muscle fatty acids (FAs) of the spiny icefish Chaenodraco wilsoni collected from three areas in the Bransfield Strait (BS), northern Antarctic Peninsula during February-April 2016 give a good representation of their feeding variability. The compositions of 22:6n3 (DHA) and 20:5n3 (EPA) were both higher in the Transitional Zonal Water with Bellingshausen influence (TBW)-controlled C. wilsoni than in the Transitional Zonal Water with Weddell Sea influence (TWW)-controlled fish. This was positively correlated with photoadaptation and carbon sequestration in TBW-controlled phytoplankton. Results for the FAs 16:1n7, 16:0, DHA and EPA indicate the presence of dinoflagellates in all three areas, suggesting that during late summer and early fall, there is a seasonal phytoplankton succession, where small phytoplankton become dominant, in the BS. In addition, the compositions of some long-chain FAs (>20, such as 20:0, 20:1, 22:0 and 22:1n9) and ∑18 indicated that the food chain based on flagellates and copepods was more apparent in TWW-controlled C. wilsoni, especially the effect of El Niño-Southern Oscillation (ENSO) on the variation of prey communities in TWW-controlled areas. FA markers such as SFA/(PUFA+MUFA), ∑15 + ∑17 and ARA were more pronounced in TWW-controlled C. wilsoni, indicating a more strongly carnivorous and benthic food source. In the TBW-TWW confluence, the complex hydrological structure, including the presence of a large number of mesoscale eddies, allows rich nutrients and krill larvae to remain in it, providing a rich food source for the C. wilsoni. Overall, the FA data of this study show that the diet of C. wilsoni varies in different marine environments, aiding their survivability at the face of climate change.


Assuntos
Euphausiacea , Animais , Regiões Antárticas , Mudança Climática , Euphausiacea/fisiologia , Cadeia Alimentar , Fitoplâncton , Estações do Ano , Água
15.
Angew Chem Int Ed Engl ; 61(15): e202201017, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35132777

RESUMO

The enrichment and purification of coal-bed methane provides a source of energy and helps offset global warming. In this work, we demonstrate a strategy involving the regulation of the pore size and pore chemistry to promote the separation of CH4 /N2 mixtures in four nickel-based coordination networks, named Ni(ina)2 , Ni(3-ain)2 , Ni(2-ain)2 , and Ni(pba)2 , (where ina=isonicotinic acid, 3-ain=3-aminoisonicotinic acid, 2-ain=2-aminoisonicotinic acid, and pba=4-(4-pyridyl)benzoic acid). Among them, Ni(ina)2 and Ni(3-ain)2 can effectively separate CH4 from N2 with top-performing performance because of the suitable pore size (≈0.6 and 0.5 nm) and pore environment. Explicitly, Ni(ina)2 exhibits the highest ever reported CH4 /N2 selectivity of 15.8 and excellent CH4 uptake (40.8 cm3 g-1 ) at ambient conditions, thus setting new benchmarks for all reported MOFs and traditional adsorbents. The exceptional CH4 /N2 separation performance of Ni(ina)2 is confirmed by dynamic breakthrough experiments. Under different CH4 /N2 ratios, Ni(ina)2 selectively extracts methane from the gaseous blend and produces a high purity of CH4 (99 %). Theoretical calculations and CH4 -loading single-crystal structure analysis provide critical insight into the adsorption/separation mechanism. Ni(ina)2 and Ni(3-ain)2 can form rich intermolecular interactions with methane, indicating a strong adsorption affinity between pore walls and CH4 molecules. Importantly, Ni(ina)2 has good thermal and moisture stability and can easily be scaled up at a low cost ($25 per kilogram), which will be valuable for potential industrial applications. Overall, this work provides a powerful approach for the selective adsorption of CH4 from coal-bed methane.

16.
Angew Chem Int Ed Engl ; 61(33): e202207066, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35674195

RESUMO

In the electronics industry, the efficient recovery and capture of sulfur hexafluoride (SF6 ) from SF6 /N2 mixtures is of great importance. Herein, three metal-organic frameworks with fine-tuning pore structures, Cu(peba)2 , Ni(pba)2 , and Ni(ina)2 , were designed for SF6 capture. Among them, Ni(ina)2 has perfect pore sizes (6 Å) that are comparable to the kinetic diameter of sulfur hexafluoride (5.2 Å), affording the benchmark binding affinity for SF6 gas. Ni(ina)2 exhibits the highest SF6 /N2 selectivity (375.1 at 298 K and 1 bar) and ultra-high SF6 uptake capacity (53.5 cm3 g-1 at 298 K and 0.1 bar) at ambient conditions. The remarkable separation performance of Ni(ina)2 was verified by dynamic breakthrough experiments. Theoretical calculations and the SF6 -loaded single-crystal structure provided critical insight into the adsorption/separation mechanism. This porous coordination network has the potential to be used in industrial applications.

17.
J Cell Physiol ; 236(3): 2058-2069, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32783191

RESUMO

The long noncoding RNA antisense noncoding RNA in the INK4 locus (ANRIL) plays a critical role in the development of atherosclerosis. However, the precise effect of ANRIL on endothelial dysfunction remains unclear. In this study, we investigated ANRIL expression in patients with coronary artery disease and elucidated the molecular mechanism underlying its effect. ANRIL expression was detected in the blood plasma of 111 patients. We analysed the correlation between ANRIL and endothelial dysfunction markers. We also examined the effect of ANRIL on the regulation of endothelial dysfunction. ANRIL levels were increased in patients with acute coronary syndrome. The expression of ANRIL is associated with the inflammatory cytokines monocyte chemoattractant protein-1 and interleukin-10, which are secreted in response to endothelial dysfunction. Knockdown of ANRIL significantly promoted cell proliferation and tubule formation and inhibited inflammatory activation and apoptosis of human umbilical vein endothelial cells (HUVEC). ANRIL-mediated inhibition of let-7b regulates HUVEC dysfunction by targeting the TGF-ßR1/Smad signalling pathway. This study highlights a new therapeutic strategy for preventing endothelial dysfunction associated with cardiovascular disease.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Transdução de Sinais , Síndrome Coronariana Aguda/genética , Sequência de Bases , Biomarcadores/metabolismo , Humanos , Inflamação/genética , Inflamação/patologia , Modelos Biológicos , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/genética , Proteínas Smad/metabolismo , Regulação para Cima/genética
18.
Mikrochim Acta ; 188(4): 141, 2021 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-33774694

RESUMO

A redox-responsive chemodynamic therapy (CDT)-based theranostic system composed of hollow mesoporous MnO2 (H-MnO2), doxorubicin (DOX), and fluorescent (FL) carbon nanodots (CDs) is reported for the diagnosis and therapy of cancer. In general, since H-MnO2 can be degraded by intracellular glutathione (GSH) to form Mn2+ with excellent Fenton-like activity to generate highly reactive ·OH, the normal antioxidant defense system can be injured via consumption of GSH. This in turn can potentiate the cytotoxicity of CDT and release DOX. The cancer cells can be eliminated effectively by the nanoplatform via the synergistic effect of chemotherapy and CDT. The FL of CDs can be restored after H-MnO2 is degraded which blocked the fluorescence resonance energy transfer process between CDs as an energy donor and H-MnO2 as an FL acceptor. The GSH can be determined by recovery of the FL and limit of detection is 1.30 µM with a linear range of 0.075-0.825 mM. This feature can be utilized to efficiently distinguish cancerous cells from normal ones based on different GSH concentrations in the two types of cells. As a kind of CDT-based theranostic system responsive to GSH, simultaneously diagnostic (normal/cancer cell differentiation) and therapeutic function (chemotherapy and CDT) in a single nanoplatform can be achieved. The redox-responsive chemodynamic therapy (CDT)-based theranostic system is fabricated by H-MnO2, DOX, and fluorescent CDs. The nanoplatform can realize simultaneously diagnostic (normal/cancer cell differentiation) and therapeutic function (chemotherapy and CDT) to improve the therapeutic efficiency and security.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Corantes Fluorescentes/química , Glutationa/análise , Medicina de Precisão/métodos , Pontos Quânticos/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carbono/química , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Tratamento Farmacológico , Humanos , Limite de Detecção , Camundongos , Molibdênio/química , Neoplasias/diagnóstico , Óxidos/química , Espectrometria de Fluorescência
19.
Mikrochim Acta ; 188(5): 154, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33821295

RESUMO

Mitochondria, as the energy factory of most cells, are not only responsible for the generation of adenosine triphosphoric acid (ATP) but also essential targets for therapy and diagnosis of various diseases, especially cancer. The safe and potential nanoplatform which can deliver various therapeutic agents to cancer cells and mitochondrial targeted imaging is urgently required. Herein, Au nanoparticles (AuNPs), mesoporous silica nanoparticles (MSN), cationic ligand (triphenylphosphine (TPP)), doxorubicin (DOX), and carbon nanodots (CDs) were utilized to fabricate mitochondrial targeting drug delivery system (denoted as CDs(DOX)@MSN-TPP@AuNPs). Since AuNPs, as the gatekeepers, can be etched by intracellular glutathione (GSH) via ligand exchange induced etching process, DOX can be released into cells in a GSH-dependent manner which results in the superior GSH-modulated tumor inhibition activity. Moreover, after etching by GSH, the CDs(DOX)@MSN-TPP@AuNPs can serve as promising fluorescent probe (λex = 633 nm, λem = 650 nm) for targeted imaging of mitochondria in living cells with near-infrared fluorescence. The induction of apoptosis derived from the membrane depolarization of mitochondria is the primary anti-tumor route of CDs(DOX)@MSN-TPP@AuNPs. As a kind of GSH-responsive mitochondrial targeting nanoplatform, it holds great promising for effective cancer therapy and mitochondrial targeted imaging. The mitochondrial targeting drug delivery system was fabricated by AuNPs, MSN, TPP, and CDs. The nanoplatform can realize redox-responsive drug delivery and targeted imaging of mitochondria in living cells to improve the therapeutic efficiency and security.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Mitocôndrias/metabolismo , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carbono/química , Carbono/toxicidade , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Corantes Fluorescentes/toxicidade , Glutationa/metabolismo , Ouro/química , Ouro/toxicidade , Humanos , Nanopartículas Metálicas/toxicidade , Camundongos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Compostos Organofosforados/química , Compostos Organofosforados/toxicidade , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Dióxido de Silício/química , Dióxido de Silício/toxicidade , Prata/química , Prata/toxicidade
20.
Angew Chem Int Ed Engl ; 60(37): 20383-20390, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34250717

RESUMO

Structural changes at the active site of an enzyme induced by binding to a substrate molecule can result in enhanced activity in biological systems. Herein, we report that the new hybrid ultramicroporous material sql-SIFSIX-bpe-Zn exhibits an induced fit binding mechanism when exposed to acetylene, C2 H2 . The resulting phase change affords exceptionally strong C2 H2 binding that in turn enables highly selective C2 H2 /C2 H4 and C2 H2 /CO2 separation demonstrated by dynamic breakthrough experiments. sql-SIFSIX-bpe-Zn was observed to exhibit at least four phases: as-synthesised (α); activated (ß); and C2 H2 induced phases (ß' and γ). sql-SIFSIX-bpe-Zn-ß exhibited strong affinity for C2 H2 at ambient conditions as demonstrated by benchmark isosteric heat of adsorption (Qst ) of 67.5 kJ mol-1 validated through in situ pressure gradient differential scanning calorimetry (PG-DSC). Further, in situ characterisation and DFT calculations provide insight into the mechanism of the C2 H2 induced fit transformation, binding positions and the nature of host-guest and guest-guest interactions.

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