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1.
Angew Chem Int Ed Engl ; 63(21): e202401005, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38584128

RESUMEN

Developing highly stable porous coordination polymers (PCPs) with integrated electrical conductivity is crucial for advancing our understanding of electrocatalytic mechanisms and the structure-activity relationship of electrocatalysts. However, achieving this goal remains a formidable challenge because of the electrochemical instability observed in most PCPs. Herein, we develop a "modular design" strategy to construct electrochemically stable semiconducting PCP, namely, Fe-pyNDI, which incorporates a chain-type Fe-pyrazole metal cluster and π-stacking column with effective synergistic effects. The three-dimensional electron diffraction (3D ED) technique resolves the precise structure. Both theoretical and experimental investigation confirms that the π-stacking column in Fe-pyNDI can provide an efficient electron transport path and enhance the structural stability of the material. As a result, Fe-pyNDI can serve as an efficient model electrocatalyst for nitrate reduction reaction (NO3RR) to ammonia with a superior ammonia yield of 339.2 µmol h-1 cm-2 (14677 µg h-1 mgcat. -1) and a faradaic efficiency of 87 % at neutral electrolyte, which is comparable to state-of-the-art electrocatalysts. The in-situ X-ray absorption spectroscopy (XAS) reveals that during the reaction, the structure of Fe-pyNDI can be kept, while part of the Fe3+ in Fe-pyNDI was reduced in situ to Fe2+, which serves as the potential active species for NO3RR.

2.
Angew Chem Int Ed Engl ; 62(47): e202312095, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37743667

RESUMEN

Crystalline triazine-based covalent organic frameworks (COFs) are aromatic nitrogen-rich porous materials. COFs typically show high thermal/chemical stability, and are promising for energy applications, but often require harsh synthesis conditions and suffer from low crystallinity. In this work, we propose an environmentally friendly route for the synthesis of crystalline COFs from CO2 molecules as a precursor. The mass ratio of CO2 conversion into COFs formula unit reaches 46.3 %. The synthesis consists of two steps; preparation of 1,4-piperazinedicarboxaldehyde from CO2 and piperazine, and condensation of the dicarboxaldehyde and melamine to construct the framework. The CO2 -derived COF has a 3-fold interpenetrated structure of 2D layers determined by powder X-ray diffraction, high-resolution transmission electron microscopy, and select-area electron diffraction. The structure shows a high Brunauer-Emmett-Teller surface area of 945 m2 g-1 and high stability against strong acid (6 M HCl), base (6 M NaOH), and boiling water over 24 hours. Post-modification of the framework with oxone has been demonstrated to modulate hydrophilicity, and it exhibits proton conductivity of 2.5×10-2  S cm-1 at 85 °C, 95 % of relative humidity.

3.
Anal Chem ; 94(4): 2023-2031, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35100803

RESUMEN

Chirality is a ubiquitous phenomenon in nature, serving as a foundation for a variety of life activities on earth. Separation-free methods that rapidly and accurately distinguish chiral analytes in complex systems are highly demanded in fields ranging from drug quality control to the screening of privileged chiral catalysts. However, in situ enantidifferentiation methods possessing resolution and tunability that are comparable to those achieved by chiral high-performance liquid chromatography are rare. Herein, we report a Lewis pair-based system for enantioanalysis via recognition-enabled "chromatographic" 19F NMR spectroscopy. The construction of Lewis pairs renders the detecting system not only enhanced affinity to chiral analytes but also superior and tunable resolving capability. Using this strategy, as many as 16 chiral analytes are simultaneously resolved without need for separation, thus opening new avenues for the development of precise and real-time detection methods that are robust enough for dealing with complex real-world samples.


Asunto(s)
Estereoisomerismo , Cromatografía Líquida de Alta Presión/métodos , Espectroscopía de Resonancia Magnética
4.
Angew Chem Int Ed Engl ; 59(15): 6007-6014, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-31930618

RESUMEN

Methods to synthesize crystalline covalent triazine frameworks (CTFs) are limited and little attention has been paid to development of hydrophilic CTFs and photocatalytic overall water splitting. A route to synthesize crystalline and hydrophilic CTF-HUST-A1 with a benzylamine-functionalized monomer is presented. The base reagent used plays an important role in the enhancement of crystallinity and hydrophilicity. CTF-HUST-A1 exhibits good crystallinity, excellent hydrophilicity, and excellent photocatalytic activity in sacrificial photocatalytic hydrogen evolution (hydrogen evolution rate up to 9200 µmol g-1 h-1 ). Photocatalytic overall water splitting is achieved by depositing dual co-catalysts in CTF-HUST-A1, with H2 evolution and O2 evolution rates of 25.4 µmol g-1 h-1 and 12.9 µmol g-1 h-1 in pure water without using sacrificial agent.

5.
Int Urol Nephrol ; 56(3): 1117-1127, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37642797

RESUMEN

PURPOSE: This study was to investigate the association between albumin-corrected anion gap (AG) (ACAG) levels and the risk of acute kidney injury (AKI) in intensive care unit (ICU) patients. METHODS: The ICU patients of this retrospective cohort study were collected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database between 2008 and 2019. ACAG = AG + {4.4 - [albumin (g/dl)]} × 2.5. The incidence of AKI was determined using the Kidney Disease: Improving Global Outcomes (KDIGO) definition. The logistic regression model was used to evaluate the association between ACAG levels and the risk of AKI. Subgroup analyses were applied based on age, gender, mechanical ventilation, vasopressors, the Charlson comorbidity index (CCI), and the Simplified Acute Physiology Score II (SAPS II). RESULTS: Totally, 5586 patients were enrolled, of which 1929 patients (34.53%) occurred AKI. The higher levels of ACAG were associated with the risk of AKI in ICU patients, with the odds ratio (OR) value being 1.23 [95% confidence interval (CI): 1.22-1.24, P = 0.005] in ACAG level between 16.5 and 19.5, and OR value being 1.20 (95% CI 1.16-1.24, P = 0.016) in ACAG level > 19.5. A higher ACAG level was associated with a higher risk of AKI in ICU patients aged < 65 years, in ICU patients of female gender, in ICU patients who used mechanical ventilation, in ICU patients who did not use vasopressors, in patients without cardiogenic shock, and in ICU patients with CCI ≥ 2, and SAPS II > 31 (all P < 0.05). CONCLUSION: There is an association between ACAG level and the risk of AKI in ICU patients. A higher ACAG value in ICU patients should therefore receive more attention.


Asunto(s)
Equilibrio Ácido-Base , Lesión Renal Aguda , Humanos , Femenino , Estudios Retrospectivos , Unidades de Cuidados Intensivos , Albúminas , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/etiología , Lesión Renal Aguda/terapia , Pronóstico
6.
Protein Pept Lett ; 30(10): 877-890, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38093594

RESUMEN

BACKGROUND: Pulmonary inflammatory response (PIR) is one of the prognostic risk factors of lung adenocarcinoma (LUAD), with a high mortality rate. OBJECTIVES: This study aims to investigate prognostic microRNA (miRNA) to improve clinical prognosis prediction and postoperative inflammation treatment in LUAD patients. METHODS: About 201 differentially expressed microRNAs (DE-miRNAs) in LUAD were mined by differential analysis. Univariate/multivariate Cox analyses established and validated prognostic risk miRNAs in TCGA-LUAD. KEGG and GO were used to link risk signatures and biological functions. After 48 hours of exposure to 50 ng/mL LPS, the miR-584-5p/RAB23 regulatory network was verified in qRT-PCR, Western Blotting, and the Luciferase Reporter Assay in A549 cells. RESULTS: MiR-584-5p and miR-101-3p were validated as riskscore correlated with LUAD patients' 1-year survival (p < 0.001) and participate in multiple inflammation-related pathways. RAB23, a RAS oncogene, is involved in inflammatory MAPK signaling. Evidence suggests that miR-584-5p regulates inflammation in LUAD by targeting RAB23. A549 cells were transfected with the mimic and inhibitor of miR-584-5p, confirming the negative regulatory relationship between miR-584-5p and RAB23. In the A549 induced by LPS, either over-expression of miR-584-5p or knock-down of RAB23 expression decreased the expression of inflammatory factors and increased cell viability. CONCLUSION: Prognostic-related risk miR-584-5p can regulate the expression of RAB23 at both the mRNA and protein levels, thereby influencing the development of a PIR in LUAD. This will have significant implications for the clinical prognosis prediction and therapy decision-making of LUAD patients with PIR.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , MicroARNs , Humanos , Lipopolisacáridos/toxicidad , Células A549 , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/patología , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Biomarcadores , Inflamación/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo
7.
Bioengineered ; 13(5): 11625-11635, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35510377

RESUMEN

Sepsis is capable of causing systemic infections resulting in multiple organ damage. Dexpanthenol (DXP) has been reported to protect against kidney and liver injury. Therefore, this paper attempts to explore the role of DXP in sepsis-induced kidney and liver injury. A mice model of sepsis was established using the cecal ligation and puncture (CLP) method. The expressions of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 and monocyte chemoattractant protein (MCP)-1 in the serum of mice were measured utilizing enzyme linked immunosorbent assay (ELISA). Additionally, the damage of kidney and liver tissues in CLP-induced mice was determined by their respective commercial kits, western blot, and hematoxylin-eosin (HE) staining kits. The apoptosis of kidney and liver tissues in CLP-induced mice was assessed by means of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and western blot. It was observed that DXP decreased the expressions of TNF-α, IL-1ß, IL-6, and MCP-1 in the serum of CLP-induced mice, attenuated the functional impairment, pathological damage, inflammation, and cell apoptosis of kidney tissue. Meanwhile, DXP decreased the functional impairment of liver in CLP-induced mice, reduced the levels of inflammatory factors and antioxidant enzymes, attenuated liver pathological damage, and decreased cell apoptosis in liver tissues. In conclusion, DXP attenuates inflammatory damage and apoptosis in kidney and liver organs in a sepsis model.


Asunto(s)
Interleucina-6 , Sepsis , Animales , Apoptosis , Modelos Animales de Enfermedad , Interleucina-6/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ácido Pantoténico/análogos & derivados , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/genética
8.
JACS Au ; 2(7): 1638-1650, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35911452

RESUMEN

The merging of good crystallinity and high dispersibility into two-dimensional (2D) layered crystalline polymers (CPs) still represents a challenge because a high crystallinity is often accompanied by intimate interlayer interactions that are detrimental to the material processibility. We herein report a strategy to address this dilemma using rationally designed three-dimensional (3D) monomers and regioisomerism-based morphology control. The as-synthesized CPs possess layered 2D structures, where the assembly of layers is stabilized by relatively weak van der Waals interactions between C-H bonds other than the usual π-π stackings. The morphology and dispersibility of the CPs are finely tuned via regioisomerism. These findings shed light on how to modulate the crystallinity, morphology, and ultimate function of crystalline polymers using the spatial arrangements of linking groups.

9.
Oncol Lett ; 21(3): 195, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33574934

RESUMEN

[This corrects the article DOI: 10.3892/ol.2015.3769.].

10.
Exp Ther Med ; 21(5): 445, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33747181

RESUMEN

MicroRNAs (miRNAs/miRs) have important roles in inflammation and infections, which are common manifestations of acute respiratory distress syndrome (ARDS). The present study aimed to assess whether serum miRNAs are potential diagnostic biomarkers for human ARDS. For this, two sets of serum samples from healthy individuals and patients with ARDS were analysed by high-throughput sequencing to identify differentially expressed genes in ARDS. A total of 679 valid sequences were identified as differentially expressed (P<0.05). Of these, five differentially expressed miRNAs were subjected to reverse transcription-quantitative PCR validation. Finally, two miRNAs (miR-584 and miR-146a) were successfully verified. These two miRNAs were significantly downregulated in the serum of patients with ARDS. Gene Ontology annotations and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that their target transcripts were implicated in a broad range of biological processes and various metabolic pathways, including involvement in the regulation of various inflammatory factors. The present study provided a framework for understanding the molecular mechanisms of ARDS and suggested that miR-584 and miR-146a are associated with ARDS and may be potential therapeutic targets.

11.
Chem Asian J ; 13(13): 1674-1677, 2018 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-29709107

RESUMEN

We report a new strategy to construct porous carbon nitride (PCN) by embedding a heptazine unit-the primary building block of carbon nitride-into the backbone of a covalent organic framework (COF). The strategy results in a new type of PCN which bears a fibrous morphology, high surface area and wide visible absorption. The photocatalytic performance was evaluated by photodegradation of an organic dye. We found that the introduction of the heptazine unit has a prominent effect on the catalytic activity, which demonstrates an effective strategy to prepare carbon nitride materials. This work opens up a new way for the preparation of carbon nitride for photocatalysis applications.

12.
Oncol Lett ; 14(3): 3705-3710, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28927135

RESUMEN

The understanding of molecular mechanisms that are involved in the development and the progression of gastric cancer (GC) are of importance for the diagnosis and treatment. The calpain system, which contains the calpains and the endogenous inhibitor, has been suggested as an important factor in the tumorigenesis and migration of colorectal adenocarcinoma, breast and ovarian cancer, and as a prognostic marker for GC. However, the expression level of calpain system proteins in GC and normal-appearing peritumoral gastric mucosa remain unknown. The present study investigated the expression of calpain-1 (CAPN1), calpain-2 (CAPN2), calpastatin and calmodulin (CaM) in GC and uninvolved gastric mucosa tissues with immunohistochemistry. Results demonstrated that CAPN2 protein level increased in GCs compared with normal tissues, while calpastatin and CaM protein level decreased. No evident alterations were observed for CAPN1. Although the protein expression of all these four proteins was not in association with the clinical variables of GC in the present study, higher calpain enzyme activity could be a negative prognostic marker, since calpains are responsible for the generation of active forms of certain proteins that facilitate the progression of cancer. The ratio of (CAPN1 × CAPN2)/(calpastatin × CaM) may serve as a potential index for diagnosis of GC.

13.
Sci Rep ; 6: 24429, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-27080716

RESUMEN

Decellularization techniques have been widely used as an alternative strategy for organ reconstruction. This study investigated the mechanical, pro-angiogenic and in vivo biocompatibility properties of decellularized airway matrices cross-linked with genipin. New Zealand rabbit tracheae were decellularized and cross-linked with genipin, a naturally derived agent. The results demonstrated that, a significant (p < 0.05) increase in the secant modulus was computed for the cross-linked tracheae, compared to the decellularized samples. Angiogenic assays demonstrated that decellularized tracheal scaffolds and cross-linked tracheae treated with 1% genipin induce strong in vivo angiogenic responses (CAM analysis). Seven, 15 and 30 days after implantation, decreased (p < 0.01) inflammatory reactions were observed in the xenograft models for the genipin cross-linked tracheae matrices compared with control tracheae, and no increase in the IgM or IgG content was observed in rats. In conclusion, treatment with genipin improves the mechanical properties of decellularized airway matrices without altering the pro-angiogenic properties or eliciting an in vivo inflammatory response.


Asunto(s)
Matriz Extracelular , Iridoides , Ingeniería de Tejidos , Andamios del Tejido , Tráquea , Animales , Materiales Biocompatibles/química , Fenómenos Biomecánicos , Embrión de Pollo , Matriz Extracelular/química , Xenoinjertos , Iridoides/química , Masculino , Ensayo de Materiales , Neovascularización Fisiológica , Conejos , Ratas , Tráquea/química
14.
Oncol Lett ; 10(6): 3434-3442, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26788147

RESUMEN

The present study aimed to investigate the inhibitory ability of ß-hydroxyisovaleryl-shikonin (ß-HIVS) on the proliferation of human cervical cancer HeLa cells and to identify the mechanism of this effect. The HeLa cells were treated with ß-HIVS and the inhibition of cell growth was detected by an MTT assay. Flow cytometry was performed to analyze the apoptosis rate and cell cycle distribution of HeLa cells. Reverse transcription-polymerase chain reaction and western blot analysis were used to examine the expression of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway proteins. The results revealed that ß-HIVS inhibited HeLa cell proliferation in a dose- and time-dependent manner. With the administration of increasing concentrations of ß-HIVS, the apoptotic rate of HeLa cells was also increased. The cell cycle was slightly arrested at the S phase, with ~6% of cells in this phase, subsequent to treatment with 10 µM ß-HIVS. In addition, ß-HIVS markedly reduced the expression levels of PI3K, AKT, mTOR and 70-kDa ribosomal protein S6 kinase in HeLa cells. ß-HIVS promoted cervical cancer cell apoptosis by inhibiting the PI3K/AKT/mTOR signaling pathway and suppressing downstream gene expression. The present study is expected to lead to the development of molecular targeted therapy for this signaling pathway as a novel method of cervical cancer treatment.

15.
J Biomed Mater Res A ; 103(4): 1509-19, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25044712

RESUMEN

Decellularization techniques have been widely used as an alternative strategy to produce matrices for organ reconstruction. This study investigated the impact of a detergent-enzymatic decellularization protocol on the extracellular matrix integrity, mechanical properties, and biocompatibility of decellularized tracheal matrices from rabbits. The tracheas of New Zealand white rabbits were decellularized using a modified detergent-enzymatic method (DEM). Antigenicity, cellularity, glycosaminoglycan content, DNA content, histoarchitecture, and mechanical properties were monitored during processing. The surface ultrastructure of the matrix was examined by scanning electron microscopy (SEM). Bioengineered and control tracheas were then implanted in major histocompatibility complex-unmatched rats (xenograft) heterotopically for 7, 15, and 30 days. Structural and functional analysis was performed after transplantation. The results showed that seven cycles of decellularization removed most of the cells and eliminated antigenicity. Histological and molecular biology analysis demonstrated that most of the cellular components and nuclear material were removed. SEM analysis revealed that the decellularized matrices retained the hierarchical structure of the native trachea, and biomechanical tests showed that decellularization did not significantly influence the mechanical properties. Seven, 15 and 30 days after implantation, decreased (p < 0.01) inflammatory reactions were observed in the xenograft models for decellularized matrices compared with control tracheas. No increases in IgM or IgG content were observed in rats that received bioengineered tracheas. In conclusion, this work suggests that seven cycles of the DEM generates a bioengineered rabbit tracheal matrix that is structurally and mechanically similar to native trachea.


Asunto(s)
Matriz Extracelular/inmunología , Tráquea/anatomía & histología , Tráquea/fisiología , Animales , Bioingeniería , Fenómenos Biomecánicos , Pollos , Membrana Corioalantoides/metabolismo , ADN/metabolismo , Matriz Extracelular/ultraestructura , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Glicosaminoglicanos/metabolismo , Xenoinjertos , Inmunohistoquímica , Masculino , Neovascularización Fisiológica , Conejos , Ratas Sprague-Dawley , Coloración y Etiquetado , Ingeniería de Tejidos , Andamios del Tejido , Tráquea/metabolismo , Tráquea/ultraestructura
16.
Med Oncol ; 31(4): 918, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24643625

RESUMEN

SOX genes play an important role in a number of developmental processes. SOXs have been demonstrated to have potential roles as either tumor suppressors or promoters in various neoplastic tissues depending on the tumor status and type. The aim of this study was to investigate the functional role of SOXs in human cancers. Gene expression changes of SOXs in human hepatocellular carcinoma (HCC) tissues were detected using real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis and immunohistochemistry and compared with those in non-cancerous hepatic tissues. We found by qRT-PCR analysis and immunohistochemistry that the gene SOX8 was significantly upregulated in HCC. Furthermore, we discovered that SOX8 promoted cancer cell proliferation in vitro and that its expression was correlated with elevated ß-catenin levels in HCC, whose function was required for the oncogenic effects of SOX8.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Factores de Transcripción SOXE/metabolismo , Proliferación Celular , Células HEK293 , Humanos , Inmunohistoquímica , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Factores de Transcripción SOXE/genética , Transducción de Señal , Factores de Tiempo , beta Catenina/metabolismo
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