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1.
Inorg Chem ; 63(10): 4574-4582, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38414342

RESUMO

The aqueous carbonation of calcium silicate (CS), a representative alkaline-earth silicate, has been widely explored in studies of carbon dioxide (CO2) mineralization. In this context, we conducted a specific comparison of the carbonation behaviors between the crystalline calcium silicate (CCS) and amorphous calcium silicate (ACS) across a pH range from 9.0 to 12.0. Interestingly, we observed opposite pH dependencies in the carbonation efficiencies (i.e., CaO conversion into CaCO3 in 1 M Na2CO3/NaHCO3 solution under ambient conditions) of CCS and ACS─the carbonation efficiency of CCS decreased with increasing the solution basicity, while that of ACS showed an inverse trend. In-depth insights were gained through in situ Raman characterizations, indicating that these differing trends appeared to originate from the polymerization/depolymerization behaviors of silicates released from minerals. More specifically, higher pH conditions seemed to favor the carbonation of minerals containing polymerized silica networks. These findings may contribute to a better understanding of the fundamental factors influencing the carbonation behaviors of alkaline earth silicates through interfacial coupled dissolution and precipitation processes. Moreover, they offer valuable insights for selecting optimal carbonation conditions for alkaline-earth silicate minerals.

2.
Nat Commun ; 15(1): 1155, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326343

RESUMO

Under-oil open microfluidic system, utilizing liquid-liquid boundaries for confinements, offers inherent advantages including clogging-free flow channels, flexible access to samples, and adjustable gas permeation, making it well-suited for studying multi-phase chemical reactions that are challenging for closed microfluidics. However, reports on the novel system have primarily focused on device fabrication and functionality demonstrations within biology, leaving their application in broader chemical analysis underexplored. Here, we present a visualization-enhanced under-oil open microfluidic system for in situ characterization of multi-phase chemical reactions with Raman spectroscopy. The enhanced system utilizes a semi-transparent silicon (Si) nanolayer over the substrate to enhance visualization in both inverted and upright microscope setups while reducing Raman noise from the substrate. We validated the system's chemical stability and capability to monitor gas evolution and gas-liquid reactions in situ. The enhanced under-oil open microfluidic system, integrating Raman spectroscopy, offers a robust open-microfluidic platform for label-free molecular sensing and real-time chemical/biochemical process monitoring in multi-phase systems.

3.
Am J Drug Alcohol Abuse ; : 1-16, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38011683

RESUMO

Background: Optimal treatments for severe alcoholic hepatitis (SAH) remain controversial. Previous network meta-analysis showed that corticosteroid (CS) combined with N-acetylcysteine (NAC) was superior in reducing short-term mortality of patients with SAH. Recently, granulocyte colony-stimulating factor (G-CSF) treatments for SAH yielded promising results.Objectives: To determine how currently available treatments affect the survival and complications of patients with SAH.Methods: The study was conducted following the guidelines of PRISMA. The data from PubMed, Embase, MEDLINE, Cochrane Library, and clinicaltrials.gov to October 2022 were searched, and patients with SAH with pharmacotherapy were included in our study. The primary outcome was short-term survival, and the other outcomes were medium- (3/6 months) or long-term (12 months) survival and complications after treatment. R software was used to establish network meta-analysis models and the result was expressed by the odd ratio (OR) value and 95% credible interval (Crls).Results: A total of 31 randomized controlled trials, including 19 treatment regimens, were enrolled in our study. As the primary outcome, G-CSF+ pentoxifylline (PTX) ranked first in one-month survival and showed significant superiority when compared with the placebo (OR 8.60, 95% Crls 1.92-45.10) and CS (OR 4.95, 95% Crls 1.11-25.53). Also, G-CSF+PTX ranked first in improving three-month survival and reducing the occurrence of infection. PTX+MTD ranked first in six-month survival, and G-CSF ranked first in twelve-month survival. CS+MTD ranked first in the occurrence of gastrointestinal bleeding and hepatorenal syndrome.Conclusions: The combination of G-CSF and PTX showed a significant benefit in improving the short-term survival of SAH patients.

4.
Front Oncol ; 13: 1278467, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37817774

RESUMO

Background: Liver cancer, especially hepatocellular carcinoma (HCC), remains a significant global health challenge. Traditional prognostic indicators for HCC often fall short in providing comprehensive insights for individualized treatment. The integration of genomics and radiomics offers a promising avenue for enhancing the precision of HCC diagnosis and prognosis. Methods: From the Cancer Genome Atlas (TCGA) database, we categorized mRNA of HCC patients by Forkhead Box M1 (FOXM1) expression and performed univariate and multivariate studies to pinpoint autonomous HCC risk factors. We deployed subgroup, correlation, and interaction analyses to probe FOXM1's link with clinicopathological elements. The connection between FOXM1 and immune cells was evaluated using the CIBERSORTx database. The functions of FOXM1 were investigated through analyses of Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). After filtering through TCGA and the Cancer Imaging Archive (TCIA) database, we employed dual-region computed tomography (CT) radiomics technology to noninvasively predict the mRNA expression of FOXM1 in HCC tissues. Radiomic features were extracted from both tumoral and peritumoral regions, and a radiomics score (RS) was derived. The performance and robustness of the constructed models were evaluated using 10-fold cross-validation. A radiomics nomogram was developed by incorporating RS and clinical variables from the TCGA database. The models' discriminative abilities were assessed using metrics such as the area under the curve (AUC) of the receiver operating characteristic curves (ROC) and precision-recall (PR) curves. Results: Our findings emphasized the overexpression of FOXM1 as a determinant of poor prognosis in HCC and illustrated its impact on immune cell infiltration. After selecting arterial phase CT, we chose 7 whole-tumor features and 3 features covering both the tumor and its surroundings to create WT and WP models for FOXM1 prediction. The WT model showed strong predictive capabilities for FOXM1 expression by PR curve. Conversely, the WP model did not demonstrate the good predictive ability. In our study, the radiomics score (RS) was derived from whole-tumor regions on CT images. The RS was significantly associated with FOXM1 expression, with an AUC of 0.918 in the training cohort and 0.837 in the validation cohort. Furthermore, the RS was correlated with oxidative stress genes and was integrated with clinical variables to develop a nomogram, which demonstrated good calibration and discrimination in predicting 12-, 36-, and 60-month survival probabilities. Additionally, bioinformatics analysis revealed FOXM1's potential role in shaping the immune microenvironment, with its expression linked to immune cell infiltration. Conclusion: This study highlights the potential of integrating FOXM1 expression and radiomics in understanding HCC's complexity. Our approach offers a new perspective in utilizing radiomics for non-invasive tumor characterization and suggests its potential in providing insights into molecular profiles. Further research is needed to validate these findings and explore their clinical implications in HCC management.

5.
Hepatol Commun ; 7(10)2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37738412

RESUMO

BACKGROUND: The Model for End-stage Liver Disease (MELD) 3.0 yields high prognostic performance for patients with end-stage liver disease (ESLD). However, its prognostic performance for patients with alcohol-related liver disease (ARLD) has limited results. The aim of this study was to perform such an evaluation among Chinese patients. METHODS: Patients hospitalized with ARLD in one institution between 2015 and 2018 were retrospectively included and followed up for 12 months. The original MELD, MELD-Na, MELD 3.0, and modified Maddrey discriminant function (MDF) scores were calculated for each patient at baseline. Their prognostic performances for 1-year survival were assessed. Time-dependent receiver operating characteristic curves were constructed, and AUCs were calculated for each scoring system. RESULTS: Among the 576 patients included in our analysis, 209 patients had alcoholic hepatitis (AH). By the 1-year follow-up, 14.8% (84/567) of all the patients and 23.4% (49/209) of those with AH had died. Overall, patients who had died had higher MELD, MELD-Na, MELD 3.0, and MDF scores (all p < 0.001) than those who had not. The same was true in the AH subgroup (MELD: p < 0.001, MELD-Na: p < 0.001, MELD 3.0: p = 0.007, MDF: p = 0.017). The AUC of the MELD 3.0 for prediction of 1-year survival among patients with ARLD was 0.682, lower than that of the original MELD (0.728, p < 0.001) and MELD-Na (0.735, p < 0.001). Moreover, in the AH subgroup, the AUC for the prediction of 1-year survival was lower than that in the MELD-Na subgroup (0.634 vs. 0.708, p < 0.001). CONCLUSIONS: The MELD 3.0 was not superior to the original MELD or the MELD-Na in predicting the mortality of patients with ARLD.


Assuntos
Doença Hepática Terminal , Hepatite Alcoólica , Humanos , Doença Hepática Terminal/diagnóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Área Sob a Curva
6.
Environ Sci Technol ; 57(37): 13808-13817, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37672711

RESUMO

Carbon dioxide (CO2) mineralization based on aqueous carbonation of alkaline earth silicate minerals is a promising route toward large-scale carbon removal. Traditional aqueous carbonation methods largely adopt acidification-based approaches, e.g., using concentrated/pressurized CO2 or acidic media, to accelerate mineral dissolution and carbonation. In this study, we designed and tested three distinctive routes to evaluate the effect of pretreatments under different pH conditions on aqueous carbonation, using amorphous calcium silicate (CS) as an example system. Pretreating CS with high concentrations (100 mM) of HCl (Route I) or NaOH (Route II and III) enhanced their carbonation degrees. However, NaOH pretreatment overall yielded higher carbonation degrees than the HCl pretreatment, with the highest carbonation degree achieved through Route III, where an extra step is taken after the NaOH pretreatment to remove the solution containing dissolved silica prior to carbonation. The HCl and NaOH pretreatments formed different intermediate silica products on the CS surface. Silica precipitated from the HCl pretreatment had a minimal effect on the carbonation degree. The high Ca/Si ratio intermediate phases formed from the NaOH, on the other hand, can be readily carbonated. In contrast to commonly utilized acidification-based approaches, basification offers a more promising route to accelerate aqueous carbonation as it can mitigate the need for costly pH swing and high-concentration/pressurized CO2. The key to aqueous carbonation under basic conditions, as suggested by this study, is the control of aqueous silica species that have a suppressing effect on carbonation. Overall, this study highlights the critical needs for investigations of aqueous mineral carbonation in a broader pH region.


Assuntos
Dióxido de Carbono , Silicatos , Hidróxido de Sódio , Dióxido de Silício , Carbonatos
8.
J Psychiatr Res ; 164: 477-484, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37441998

RESUMO

Baclofen is the only drug that has been investigated in randomized controlled studies for anti-craving in patients with alcohol use disorder (AUD) and liver disease. However, the results of its efficacy are controversial due to limited case numbers; therefore, a meta-analysis of all available studies is needed to verify efficacy and safety in this population. This systematic review and meta-analysis were conducted according to the Cochrane Collaboration Handbook (PROSPERO ID: CRD42021284439) clauses. PubMed, Embase, Medline, Cochrane, and Clinical Trials. Gov were searched for patients with AUD co-morbid liver diseases who used baclofen to maintain abstinence. The primary outcome was maintaining abstinence. Baclofen safety was evaluated by adverse reaction occurrence during treatment. A total of 322 patients with AUD co-morbid liver diseases (alcohol-related liver disease, hepatitis C, or cirrhosis) from five studies were included. The total abstinence rate was 53% (95% CI: 0.23-0.84). Specifically, the abstinence rate in patients with alcohol-related liver disease and cirrhosis was 63% and 55%, respectively. We further analyzed the two included randomized controlled studies to compare the efficacy between baclofen and a placebo. There was no significant difference in abstinence rates between baclofen and the placebo (RR: 1.42, 95% CI: 0.41-4.92). One serious adverse event was reported, and no cases of baclofen addiction were found. The abstinence rate in patients with AUD co-morbid liver diseases was 53%; however, the efficacy of baclofen for maintaining abstinence in this population still needs to be validated with further studies.


Assuntos
Alcoolismo , Hepatopatias , Humanos , Alcoolismo/complicações , Alcoolismo/tratamento farmacológico , Baclofeno/efeitos adversos , Consumo de Bebidas Alcoólicas , Hepatopatias/complicações , Hepatopatias/tratamento farmacológico , Fissura
9.
J Exp Clin Cancer Res ; 42(1): 138, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264406

RESUMO

BACKGROUND: Breast cancer (BC) negatively impacts the health of women worldwide. Circular RNAs (circRNAs) are a group of endogenous RNAs considered essential regulatory factor in BC tumorigenesis and progression. However, the underlying molecular mechanisms of circRNAs remain unclear. METHODS: Expression levels of circPAPD4, miR-1269a, CREBZF, and ADAR1 in BC cell lines and tissues were measured using bioinformatics analysis, RT-qPCR, ISH, and IHC. Cell proliferation and apoptosis were measured using CCK8, EdU staining, flow cytometry, and TUNEL assays. Pearson correlation analysis, RNA pull-down, dual-luciferase reporter, and co-immunoprecipitation assays were used to explore the correlation among circPAPD4, miR-1269a, CREBZF, STAT3, and ADAR1. Effects of circPAPD4 overexpression on tumor progression were investigated using in vivo assays. Moreover, CREBZF mRNA delivered by polymeric nanoparticles (CREBZF-mRNA-NPs) was used to examine application value of our findings. RESULTS: CircPAPD4 expression was low in BC tissues and cells. Functionally, circPAPD4 inhibited proliferation and promoted apoptosis in vitro and in vivo. Mechanistically, circPAPD4 biogenesis was regulated by ADAR1. And circPAPD4 promoted CREBZF expression by competitively binding to miR-1269a. More importantly, CREBZF promoted circPAPD4 expression by suppressing STAT3 dimerization and ADAR1 expression, revealing a novel positive feedback loop that curbed BC progression. Systematic delivery of CREBZF-mRNA-NPs effectively induced CREBZF expression and activated the positive feedback loop of circPAPD4/miR-1269a/CREBZF/STAT3/ADAR1, which might suppress BC progression in vitro and in vivo. CONCLUSION: Our findings firstly illustrated that circPAPD4/miR-1269a/CREBZF/STAT3/ADAR1 positive feedback loop mediated BC progression, and delivering CREBZF mRNA nanoparticles suppressed BC progression in vitro and in vivo, which might provide novel insights into therapeutic strategies for breast cancer.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , Neoplasias da Mama/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Mensageiro , Retroalimentação , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo
10.
J Phys Chem Lett ; 14(20): 4711-4718, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37171173

RESUMO

Photocatalytic hydrogen production via water splitting has been a promising method to produce clean energy and effectively reduce environmental pollution. Herein, a specific bandgap-oriented structure search was performed. A two-dimensional (2D) carbon structure comprising triatomic and hexatomic carbon rings, named 2D tri-hex carbon, was proposed to possess suitable bandgap and band edge positions for photocatalytic water splitting. Our results show that 2D tri-hex carbon has a high absorption coefficient under sunlight and high photocatalytic water-splitting efficiency under acidic conditions. The study provides insight into exploring a promising candidate in 2D carbon materials for acid-corrosion-resistant photocatalytic water-splitting applications.

11.
Int J Nanomedicine ; 18: 1677-1693, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020690

RESUMO

Background: Circular RNAs (circRNAs) are becoming vital biomarkers and therapeutic targets for malignant tumors due to their high stability and specificity in tissues. However, biological functions of circRNAs in hepatocellular carcinoma (HCC) are still not well studied. Methods: Gene Expression Omnibus (GEO) database and qRT-PCR were used to evaluate expression of circROBO1 (hsa_circ_0066568) in HCC tissues and cell lines. CCK-8, colony formation, EdU staining, flow cytometry for cell cycle analysis, and xenograft model assays were performed to detect the circROBO1 function in vitro and in vivo. RNA pull-down, RNA immunoprecipitation (RIP), and Luciferase reporter assays were used to investigate the relationship among circROBO1, miR-130a-5p, and CCNT2. More importantly, we developed nanoparticles made from poly lactic-co-glycolic acid (PLGA) and polyethylene glycol (PEG) chains as the delivery system of si-circROBO1 and then applied them to HCC in vitro and in mice. Results: circROBO1 was obviously upregulated in HCC tissues and cell lines, and elevated circROBO1 was closely correlated with worse prognosis for HCC patients. Functionally, knocking down circROBO1 significantly suppressed HCC cells growth in vitro and in mice. Mechanistically, circROBO1 acted as a competing endogenous RNA to downregulate miR-130a-5p, leading to CCNT2 expression upregulation. Furthermore, miR-130a-5p mimic or CCNT2 knockdown reversed the role of circROBO1 overexpression on HCC cells, which demonstrated that circROBO1 promoted HCC development via miR-130a-5p/CCNT2 axis. In addition, we developed nanoparticles loaded with si-circROBO1, named as PLGA-PEG (si-circROBO1) NPs, which significantly prevented the proliferation of HCC cells, and did not exhibit apparent toxicity to major organs in vivo. Conclusion: Our findings firstly demonstrate that circROBO1 overexpression promotes HCC progression by regulating miR-130a-5p/CCNT2 axis, which may serve as an effective nanotherapeutic target for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Nanopartículas , Humanos , Animais , Camundongos , RNA Circular , Glicóis , Proliferação de Células , Linhagem Celular Tumoral , Ciclina T
12.
Epigenetics ; 18(1): 2192438, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36989117

RESUMO

Ferroptosis is a newly characterized form of iron-dependent non-apoptotic cell death, which is closely associated with cancer progression. However, the functions and mechanisms in regulation of escaping from ferroptosis during hepatocellular carcinoma (HCC) progression remain unknown. In this study, we reported that the RNA binding motif single stranded interacting protein 1 (RBMS1) participated in HCC development,and functioned as a regulator of ferroptosis. Clinically, the downregulation of RBMS1 occurred in HCC tissues, and low RBMS1 expression was associated with worse HCC patients survival. Mechanistically, RBMS1 overexpression inhibited HCC cell growth by attenuating the expression of glutathione peroxidase 4 (GPX4)and further facilitated ferroptosis in vitro and in vivo. More importantly, a novel circIDE (hsa_circ_0000251) was identified to elevate RBMS1 expression via sponging miR-19b-3p in HCC cells. Collectively, our findings established circIDE/miR-19b-3p/RBMS1 axis as a regulator of ferroptosis, which could be a promising therapeutic target and prognostic factor.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Ferroptose/genética , Linhagem Celular Tumoral , RNA Circular/genética , Metilação de DNA , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a RNA/genética
13.
Plant Phenomics ; 5: 0024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36930773

RESUMO

Plant trichomes are epidermal structures with a wide variety of functions in plant development and stress responses. Although the functional importance of trichomes has been realized, the tedious and time-consuming manual phenotyping process greatly limits the research progress of trichome gene cloning. Currently, there are no fully automated methods for identifying maize trichomes. We introduce TrichomeYOLO, an automated trichome counting and measuring method that uses a deep convolutional neural network, to identify the density and length of maize trichomes from scanning electron microscopy images. Our network achieved 92.1% identification accuracy on scanning electron microscopy micrographs of maize leaves, which is much better performed than the other 5 currently mainstream object detection models, Faster R-CNN, YOLOv3, YOLOv5, DETR, and Cascade R-CNN. We applied TrichomeYOLO to investigate trichome variations in a natural population of maize and achieved robust trichome identification. Our method and the pretrained model are open access in Github (https://github.com/yaober/trichomecounter). We believe TrichomeYOLO will help make efficient trichome identification and help facilitate researches on maize trichomes.

14.
ACS Biomater Sci Eng ; 9(2): 601-607, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36722128

RESUMO

Multistep mineralization processes are pivotal in the fabrication of functional materials and are often characterized by far from equilibrium conditions and high supersaturation. Interestingly, such 'nonclassical' mineralization pathways are widespread in biological systems, even though concentrating molecules well beyond their saturation level is incompatible with cellular homeostasis. Here, we show how polymer phase separation can facilitate bioinspired silica formation by passively concentrating the inorganic building blocks within the polymer dense phase. The high affinity of the dense phase to mobile silica precursors generates a diffusive flux against the concentration gradient, similar to dynamic equilibrium, and the resulting high supersaturation leads to precipitation of insoluble silica. Manipulating the chemistry of the dense phase allows to control the delicate interplay between polymer chemistry and silica precipitation. These results connect two phase transition phenomena, mineralization and coacervation, and offer a framework to achieve better control of mineral formation.


Assuntos
Polímeros , Dióxido de Silício , Dióxido de Silício/química
15.
Environ Toxicol ; 38(5): 1022-1037, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36715182

RESUMO

Microvascular invasion (MVI) is a crucial risk factor related to the metastasis of hepatocellular carcinoma (HCC), but the underlying mechanisms remain to be revealed. Characterizing the inherent mechanisms of MVI may aid in the development of effective treatment strategies to improve the prognosis of HCC patients with metastasis. Through the Gene Expression Omnibus (GEO) database, we identified that small nuclear ribonucleoprotein polypeptide A (SNRPA) was related to MVI in HCC. SNRPA was overexpressed in MVI-HCC and correlated with poor patient survival. Mechanistically, SNRPA promoted the epithelial-mesenchymal transition (EMT)-like process for HCC cells to accelerate metastasis by activating the NOTCH1/Snail pathway in vitro and in vivo. Importantly, circSEC62 upregulated SNRPA expression in HCC cells via miR-625-5p sponging. Taking these results together, our study identified a novel regulatory mechanism among SNRPA, miR-625-5p, circSEC62 and the NOTCH1/Snail pathway in HCC, which promoted metastasis of HCC and may provide effective suggestions for improving the prognosis of HCC patients with metastasis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Metástase Neoplásica , Fatores de Processamento de RNA , RNA Circular , Humanos , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Peptídeos/genética , Peptídeos/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , RNA Circular/metabolismo
16.
J Am Chem Soc ; 144(47): 21640-21647, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36384291

RESUMO

Nitrogen-rich compounds have attracted significant fundamental and practical interest owing to their ability to accommodate diverse nitrogen-bonding patterns and their feasibility as high-energy-density materials. Herein, we examine a wide range of chemical compositions in the compressed Ga-N system using first-principles structural search and experimental preparation using a laser-heated diamond anvil cell. Our investigations have theoretically identified three thermodynamically stable stoichiometries─GaN15, GaN10, and GaN5─with surprisingly versatile polymeric nitrogen framework topologies. Strikingly, our results show that the required synthetic pressures for forming polymeric nitrogen phases in GaN10 and GaN5 are much lower than that for pure solid nitrogen. Finally, we evaluated the energy involved in decomposing the compounds and validated that they are promising candidates for high-energy-density materials. These findings have broad implications for designing and synthesizing novel nitrogen-rich compounds through the reaction between p electron elements and nitrogen at modest pressures and for nitrogen chemistry under extreme conditions.

17.
World J Clin Cases ; 10(30): 11172-11177, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36338225

RESUMO

BACKGROUND: Hepatic myelopathy (HM) is a rare neurological complication of advanced cirrhosis. Prognosis of patients with HM is generally poor without timely liver transplantation or interventional therapy. Self-resolving HM in patients with alcoholic cirrhosis has never been reported. CASE SUMMARY: A 53-year-old man with alcoholic cirrhosis and recurrent overt hepatic encephalopathy for 1 year was admitted for lower extremity weakness, slow movement, and stumbling gait. The patient was diagnosed with HM after excluding other causes of spastic paraparesis. The patient refused liver transplantation. However, the patient kept total abstinence and received a multidisciplinary treatment for complications of decompensated cirrhosis. The symptoms of HM resolved gradually after 2 years of treatment. All complications of alcoholic cirrhosis resolved after 4 years of follow-up. CONCLUSION: The case demonstrates that HM can resolve in patients without liver transplan-tation after total abstinence and systemic management of complications.

18.
Inorg Chem ; 61(33): 13191-13198, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35943777

RESUMO

Organic-inorganic hybrid metal-polyphenols as stable structural modules have gained extensive interest due to their diverse applications. However, titanium-oxo compounds (TOCs) with large molecular polyphenols have been less explored, and they were expected to be different from small polyphenols with isolated metal ions. Herein, 4-methyl-esculetin (Mesc), a catechol derivative, was selected to construct three TOCs, namely, [Ti17O24(Mesc)4(OiPr)16] (1), [Ti12O14(OiPr)18][Ti16O14(Mesc)12(OiPr)14] (2), and [Ti3O(Mesc)2(OAc)2(OiPr)4] (3). These compounds were structurally characterized. Photocurrent responses were evaluated using the compound-sensitized TiO2 electrodes. It was found that the current densities of 1-3 electrodes are in the order of 1 ≫ 3 > 2, which relates to the ligand-to-TiO core and ligand-to-ligand charge transfers (LMCT and LLCT, respectively). Density functional theory calculations showed that the lowest band gap of 1 originates from its LLCT. Compound 1 reacted with polyphenol tannin (TA) to form a fully transparent and robust gel (1-TA), and the gelation properties were investigated. Using the gel as a nano-TiO2 fixing agent, solar cell electrodes were prepared by a low-temperature wet method. The photocurrent responsive behavior of the 1-TA/TiO2 electrode was compared with that of the 1-sensitized traditional high-temperature-treated TiO2 electrode. Although the current density of the former is somewhat lower than that of the traditional electrode, the low-temperature wet preparation of the 1-TA/TiO2 electrode is more energy-efficient and sustainable.

19.
Inorg Chem ; 61(9): 4024-4032, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35179867

RESUMO

Photoelectrocatalysis (PEC) has shown great advantages in sustainable organic synthesis and wastewater treatment because the PEC process can minimize electron-hole recombination, thereby improving the photocatalytic performance. Here, we report a convenient procedure for preparing immobilized BiOX-TiO2 photoelectrocatalytic electrodes from a titanium-oxo compound (TOC)-modified carbon fiber cloth (CFC). Crystalline TOCs composed of Ti12 cations and bismuth halide anions, [Ti12O14(OiPr)18][Bi3Br11(THF)2] (1) and [Ti12O14(OiPr)18][Bi4I14(THF)2] (2), were grown on CFC. Taking advantage of the easy hydrolysis of the titanium-oxo cation and bismuth halide anion, we could easily transform these CFC-immobilized crystals into BiOX-TiO2/CFC (X = Br or I) photocatalysts, which facilitates recycling of the catalysts. The photocatalytic dye degradation test showed that the efficiency did not decrease obviously after 10 photocatalytic cycles. Using BiOX-TiO2-modified CFC as electrodes, electrocatalysis (EC), photocatalysis (PC), and PEC were examined. PEC showed an attractive synergistic effect of EC and PC. These TOC-modified CFCs would be potential candidates for catalytic electrodes for sustainable wastewater purification.

20.
Angew Chem Int Ed Engl ; 61(17): e202115930, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35187784

RESUMO

In nature, simple organisms evolved mechanisms to form intricate biosilica nanostructures, far exceeding current synthetic manufacturing. Based on the properties of extracted biomacromolecules, polycation-polyanion pairs were suggested as moderators of biosilica formation. However, the chemical principles of this polymer-induced silicification remain unclear. Here, we used a biomimetic polycation-polyanion system to study polymer-induced silicification. We demonstrate that it is the polymer phase separation process, rather than silica-polymer interactions, which controls silica precipitation. Since ionic strength controls this electrostatic phase separation, it can be used to tune the morphology and structure of the precipitates. In situ cryo electron microscopy highlights the pivotal role of the hydrated polymer condensates in this process. These results pave the road for developing nanoscale morphologies of bioinspired silica based on the chemistry of liquid-liquid phase separation.


Assuntos
Nanoestruturas , Polímeros , Biomimética , Polímeros/química , Dióxido de Silício/química , Eletricidade Estática
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