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Constructing a Z-scheme heterostructure on a metal-organic framework (MOF) composite with an explicit charge transfer mechanism at the interface is considered to be an effective strategy for improving the photocatalytic performance of MOFs. Herein, an internal electric field (IEF)-induced Z-scheme heterostructure on the ZnIn2S4@NH2-MIL-125 composite is designed and fabricated by a facile electrostatic self-assembly process. Systematic investigations reveal that close interfacial contact and difference in work function between NH2-MIL-125 and ZnIn2S4 enable the formation of the IEF, which drives the Z-scheme charge transfer as revealed by the in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS), photoirradiated Kelvin probe force microscope (KPFM) measurement, electron paramagnetic resonance (EPR) radical trapping experiment, as well as density functional theory (DFT) calculation; meanwhile, directions of the interfacial IEFs are determined. Benefiting from the unique merit of IEF-induced Z-scheme charge transfer, the optimized ZnIn2S4@NH2-MIL-125 composite exhibits significantly enhanced photocatalytic activity for the photoreduction of 4-nitroaniline (4-NA) to p-phenylenediamine (PPD) under visible light irradiation. This work not only provides in-depth insights for charge transfer in the IEF-induced Z scheme heterostructure but also affords useful inspirations on designing the Z-scheme MOF composite to boost the photocatalytic performance.
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OBJECTIVES: To study the distribution, drug resistance, and biofilm characteristics of carbapenem-resistant Acinetobacter baumannii (CRAB) isolated from hospitalized children, providing a reference for the prevention and treatment of CRAB infections in hospitalized children. METHODS: Forty-eight CRAB strains isolated from January 2019 to December 2022 were classified into epidemic and sporadic strains using repetitive extragenic palindromic sequence-based polymerase chain reaction. The drug resistance, biofilm phenotypes, and gene carriage of these two types of strains were compared. RESULTS: Both the 22 epidemic strains and the 26 sporadic strains were producers of Class D carbapenemases or extended-spectrum ß-lactamases with downregulated outer membrane porins, harboring the VIM, OXA-23, and OXA-51 genes. The biofilm formation capability of the sporadic strains was stronger than that of the epidemic strains (P<0.05). Genes related to biofilm formation, including Bap, bfs, OmpA, CsuE, and intI1, were detected in both epidemic and sporadic strains, with a higher detection rate of the intI1 gene in epidemic strains (P<0.05). CONCLUSIONS: CRAB strains are colonized in the hospital, with sporadic strains having a stronger ability to form biofilms, suggesting the potential for forming new clonal transmissions in the hospital. Continuous monitoring of the epidemic trends of CRAB and early warning of the distribution of epidemic strains are necessary to reduce the risk of CRAB infections in hospitalized children.
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Infecciones por Acinetobacter , Acinetobacter baumannii , Biopelículas , Carbapenémicos , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/genética , Biopelículas/efectos de los fármacos , Carbapenémicos/farmacología , Humanos , Niño , Infecciones por Acinetobacter/microbiología , Preescolar , beta-Lactamasas/genética , Niño Hospitalizado , Farmacorresistencia Bacteriana/genética , Antibacterianos/farmacología , Femenino , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Proteínas Bacterianas/genéticaRESUMEN
A pyrene-based metal-organic framework, Cd2(PTTB)(H2O)2 (WYU-11), was synthesized from the tetracarboxylic pyrene ligand H4PTTB (H4PTTB = 1,3,6,8-tetrakis(3-carboxyphenyl)pyrene) and Cd(NO3)2·4H2O. Powder X-ray diffraction analysis discloses that the framework is stable in acid, base, and various organic solvent environments. WYU-11 shows excellent catalytic performance on the cyclization reaction of propargylic amines with CO2 into 2-oxazolidinones under mild conditions (60 °C, atmospheric CO2). 1H NMR studies unveiled that WYU-11 and 1,1,3,3-tetramethylguanidine (TMG) can synergistically activate the propargylic amine substrate and promote the reaction. Importantly, WYU-11 represents a rare example of noble metal-free heterogeneous catalyst that can catalyze the cyclization of CO2 with propargylic amines. In addition, by virtue of the excellent water stability and luminescence properties, WYU-11 shows excellent detection performance for sulfathiazole (STZ) and ornidazole (ODZ) in water. Investigation reveals that the coexistence of photoinduced electron transfer and internal filtering effect could reasonably explain the luminescence quenching of WYU-11 by the antibiotics.
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Aminas , Estructuras Metalorgánicas , Aminas/química , Antibacterianos , Dióxido de Carbono/química , Ciclización , Agua , Cadmio , PirenosRESUMEN
BACKGROUND: Success rate of transcatheter aortic valve replacement (TAVR) in aortic regurgitation (AR) patients is relatively low on account of the absence of calcified anchoring structures. Morphological classification and corresponding TAVR strategies for AR are lacking yet. METHODS: The AURORA study is a prospective, multicenter, single-arm cohort study to evaluate the safety and efficacy of transfemoral TAVR for severe AR in patients with high or prohibitive risk for surgery. Patients who are ≥ 65 years and diagnosed with severe pure AR as defined by the Echocardiographic Core Laboratory will be consecutively enrolled for further multidetector computed tomography (MDCT) scanning and multiplanar analyses. Based on a new anatomical classification and dual anchoring theory, patients will be classified into 4 types according to the level of the anchoring area. Types 1, 2 and 3 (at least 2 anchoring areas) will undergo the TAVR procedure with a domestic Chinese self-expanding valve (VitaFlow Valve, MicroPort, Shanghai, China), whereas type 4 (0 or 1 anchoring area) patients will be considered unsuitable for TAVR and will receive medical treatment. Our goal is to recruit 100 patients to account for 10% missing data or loss of patients to follow-up. Procedural, 30-day, 6-month and 12-month outcomes will be assessed according to Valve Academic Research Consortium-3 criteria. DISCUSSION: The AURORA study will establish a new AR anatomical classification based on dual anchoring theory through MDCT multiplanar measurement and assess the safety and efficacy of TAVR guided by this new classification and strategy in AR patients. TRIAL REGISTRATION: This Study was registered at Chinses Clinical Trial Registry. The registration number: ChiCTR2200055415; The date of registration: 9, January 2022; The URL of the registration: http://www.chictr.org.cn/showproj.aspx?proj=141209 .
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Insuficiencia de la Válvula Aórtica , Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , China , Estudios de Cohortes , Humanos , Estudios Prospectivos , Diseño de Prótesis , Factores de Riesgo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del TratamientoRESUMEN
BACKGROUND: Although Helicobacter pylori (Hp) as high risk factor for gastric cancer have been investigated from human trial, present data is inadequate to explain the effect of Hp on the changes of metabolic phenotype of gastric cancer in different stages. PURPOSE: Herein, plasma of human superficial gastritis (Hp negative and positive), early gastric cancer and advanced gastric cancer analyzed by UPLC-HDMS metabolomics can not only reveal metabolic phenotype changes in patients with gastric cancer of different degrees (30 Hp negative, 30 Hp positive, 20 early gastric cancer patients, and 10 advanced gastric cancer patients), but also auxiliarily diagnose gastric cancer. RESULTS: Combined with multivariate statistical analysis, the results represented biomarkers different from Hp negative, Hp positive, and the alterations of metabolic phenotype of gastric cancer patients. Forty-three metabolites are involved in amino acid metabolism, and lipid and fatty acid metabolism pathways in the process of cancer occurrence, especially 2 biomarkers glycerophosphocholine and neopterin, were screened in this study. Neopterin was consistently increased with gastric cancer progression and glycerophosphocholine tended to consistently decrease from Hp negative to advanced gastric cancer. CONCLUSION: This method could be used for the development of rapid targeted methods for biomarker identification and a potential diagnosis of gastric cancer.
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Gastritis/diagnóstico , Gastritis/patología , Helicobacter pylori/aislamiento & purificación , Metabolómica/métodos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Biomarcadores de Tumor , Diagnóstico Diferencial , Humanos , Estadificación de Neoplasias , Neopterin/sangre , Fenotipo , Análisis de Componente PrincipalRESUMEN
Maternal high-fat diet (HFD) is associated with metabolic syndrome and cardiovascular diseases in adult offspring. Our previous study demonstrated that maternal HFD enhances pressor responses to ANG II or a proinflammatory cytokine (PIC), which is associated with increased expression of brain renin-angiotensin system (RAS) components and PICs in adult offspring. The present study further investigated whether inhibition of angiotensin-converting enzyme (ACE) or tumor necrosis factor-α (TNF-α) blocks sensitization of ANG II hypertension in offspring of HFD dams. All offspring were bred from dams with normal fat diet (NFD) or HFD starting two weeks before mating and maintained until weaning of the offspring. Then the weaned offspring were treated with an ACE inhibitor (captopril) or a TNF-α inhibitor (pentoxifylline) in the drinking water through the end of testing with a slow-pressor dose of ANG II. RT-PCR analyses of the lamina terminalis and paraventricular nucleus revealed upregulation of mRNA expression of several RAS components and PICs in male offspring of HFD dams when compared with age-matched offspring of NFD dams. The enhanced gene expression was attenuated by blockade of either RAS or PICs. Likewise, ANG II administration produced an augmented pressor response in offspring of HFD dams. This was abolished by either ACE or TNF-α inhibitor. Taken together, this study provides mechanistic evidence and a therapeutic strategy that systemic inhibition of the RAS and PICs can block maternal HFD-induced sensitization of ANG II hypertension, which is associated with attenuation of brain RAS and PIC expression in offspring.
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Angiotensina II , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Antihipertensivos/farmacología , Presión Sanguínea/efectos de los fármacos , Captopril/farmacología , Dieta Alta en Grasa , Hipertensión/prevención & control , Pentoxifilina/farmacología , Efectos Tardíos de la Exposición Prenatal , Inhibidores del Factor de Necrosis Tumoral/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatología , Modelos Animales de Enfermedad , Femenino , Hipertensión/inducido químicamente , Hipertensión/metabolismo , Hipertensión/fisiopatología , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Embarazo , Ratas Sprague-Dawley , Sistema Renina-Angiotensina/efectos de los fármacosRESUMEN
Hepatic ischemia-reperfusion (IR) injury is the leading cause of liver dysfunction and failure after liver resection or transplantation and lacks effective therapeutic strategies. Here, we applied a systematic proteomic analysis to identify the prominent contributors to IR-induced liver damage and promising therapeutic targets for this condition. Based on an unbiased proteomic analysis, we found that toll-interacting protein (Tollip) expression was closely correlated with the hepatic IR process. RNA sequencing analysis and phenotypic examination showed a dramatically alleviated hepatic IR injury by Tollip deficiency both in vivo and in hepatocytes. Mechanistically, Tollip interacts with apoptosis signal-regulating kinase 1 (ASK1) and facilitates the recruitment of tumor necrosis factor receptor-associated factor 6 (TRAF6) to ASK1, leading to enhanced ASK1 N-terminal dimerization and the subsequent activation of downstream mitogen-activated protein kinase (MAPK) signaling. Furthermore, the Tollip methionine and phenylalanine motif and TRAF6 ubiquitinating activity are required for Tollip-regulated ASK1-MAPK axis activation. Conclusion: Tollip is a regulator of hepatic IR injury by facilitating ASK1 N-terminal dimerization and the resultant c-Jun N-terminal kinase/p38 signaling activation. Inhibiting Tollip or its interaction with ASK1 might be promising therapeutic strategies for hepatic IR injury.
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Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/fisiología , Hígado/irrigación sanguínea , Proteómica , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/etiología , Animales , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Known for excellent stability, porosity and functionality, the high-valent Zr4+ metal-organic frameworks (Zr-MOFs) still meets synthetic challenge in modulating the strength of Zr-Ocarboxylate linkage. Herein we explore the unusual coordination dynamics of fluorinated Zr-MOFs by designing two trifluoromethyl modified ligands with distinct geometry preference to form a family of thermodynamic and kinetic products. The low-connecting kinetic Zr-MOFs possess substitutable coordination sites to endow Zr6 -cluster with extra dynamic behaviors, thus opening a post-synthetic pathway to sequential reassembly/disassembly processes. Comprehensive factors, including ligand geometry, Zr6 -cluster connectivity, acid modulator and reaction temperature/concentration, have been studied for controllable syntheses. The stability, hydrophobicity and gas adsorption/separation properties of obtained Zr-MOFs are explored. This work sheds light on the understanding of the dynamic coordination chemistry of Zr-MOFs beyond strong Zr-O bond, which poses a versatile platform for modification and functionalization of Zr-MOFs.
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A flexible-robust copper(II) metal-organic framework, denoted as LIFM-100, has been successfully synthesized using a fluorinated linear dicarboxylate to link copper ions. LIFM-100 exhibits a breathing effect, which can transform reversibly between a large form (lp) and a narrow form (np) from single crystal to single crystal. In addition, LIFM-100 shows good thermal and chemical stability. By the introduction of trifluoromethyl functional groups and uncoordinated carboxyl acids, LIFM-100 features a good CO2/R22 adsorption/separation performance at 298 K, showing potential in natural gas purification and CO2/R22 capture.
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BACKGROUND: Barbarea vulgaris is a wild cruciferous plant and include two distinct types: the G- and P-types named after their glabrous and pubescent leaves, respectively. The types differ significantly in resistance to a range of insects and diseases as well as glucosinolates and other chemical defenses. A high-density linkage map was needed for further progress to be made in the molecular research of this plant. RESULTS: We performed restriction site-associated DNA sequencing (RAD-Seq) on an F2 population generated from G- and P-type B. vulgaris. A total of 1545 SNP markers were mapped and ordered in eight linkage groups, which represents the highest density linkage map to date for the crucifer tribe Cardamineae. A total of 722 previously published genome contigs (50.2 Mb, 30% of the total length) can be anchored to this high density genetic map, an improvement compared to a previously published map (431 anchored contigs, 38.7 Mb, 23% of the assembly genome). Most of these (572 contigs, 31.2 Mb) were newly anchored to the map, representing a significant improvement. On the basis of the present high-density genetic map, 37 QTL were detected for eleven traits, each QTL explaining 2.9-71.3% of the phenotype variation. QTL of glucosinolates, leaf size and color traits were in most cases overlapping, possibly implying a functional connection. CONCLUSIONS: This high-density linkage map and the QTL obtained in this study will be useful for further understanding of the genetic of the B. vulgaris and molecular basis of these traits, many of which are shared in the related crop watercress.
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Barbarea/genética , Mapeo Cromosómico/métodos , Sitios de Carácter Cuantitativo , Análisis de Secuencia de ADN/métodos , Barbarea/fisiología , ADN de Plantas/genética , Ligamiento Genético , Fenotipo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Polimorfismo de Nucleótido SimpleRESUMEN
A trifluoromethyl functionalized linker and Cu-O chain composed MOF, LIFM-100, was used as "crystalline sponge" to determine eight hardly crystallized liquids' configurations based on its flexibility conformation, suitable pore size, electron-rich channel environment, and low symmetric space group. The H bond interactions between host-guest and guest-guest were well analyzed.
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We transformed the hydrophilic metal-organic framework (MOF) UiO-67 into hydrophobic UiO-67-Rs (R=alkyl) by introducing alkyl chains into organic linkers, which not only protected hydrophilic Zr6 O8 clusters to make the MOF interspace superoleophilic, but also led to a rough crystal surface beneficial for superhydrophobicity. The UiO-67-Rs displayed high acid, base, and water stability, and long alkyl chains offered better hydrophobicity. Good hydrophobicity/oleophilicity were also possible with mixed-ligand MOFs containing metal-binding ligands. Thus, a (super)hydrophobic MOF catalyst loaded with Pd centers efficiently catalyzed Sonogashira reactions in water at ambient temperature. Studies of the hydrophobic effects of the coordination interspace and the outer surface suggest a simple deâ novo strategy for the synthesis of superhydrophobic MOFs that combine surface roughness and low surface energy. Such MOFs have potential for environmentally friendly catalysis and water purification.
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Accumulating evidence indicates that maternal high-fat diet (HFD) is associated with metabolic syndrome and cardiovascular disease in adult offspring. The present study tested the hypothesis that maternal HFD modulates the brain renin-angiotensin system (RAS), oxidative stress, and proinflammatory cytokines that alter angiotensin II (ANG II) and TNF-α actions and sensitize the ANG II-elicited hypertensive response in adult offspring. All offspring were cross fostered by dams on the same or opposite diet to yield the following four groups: offspring from normal-fat control diet-fed dams suckled by control diet-fed dams (OCC group) or by HFD-fed dams (OCH group) and offspring from HFD-fed dams fed a HFD suckled by control diet-fed dams (OHC group) or by HFD-fed dams (OHH group). RT-PCR analyses of the lamina terminalis and paraventricular nucleus indicated upregulation of mRNA expression of several RAS components, NADPH oxidase, and proinflammatory cytokines in 10-wk-old male offspring of dams fed a HFD during either pregnancy, lactation, or both (OHC, OCH, and OHH groups). These offspring also showed decreased cardiac baroreflex sensitivity and increased pressor responses to intracerebroventricular microinjection of either ANG II or TNF-α. Furthermore, chronic systemic infusion of ANG II resulted in enhanced upregulation of mRNA expression of RAS components, NADPH oxidase, and proinflammatory cytokines in the lamina terminalis and paraventricular nucleus and an augmented hypertensive response in the OHC, OCH, and OHH groups compared with the OCC group. The results suggest that maternal HFD blunts cardiac baroreflex function and enhances pressor responses to ANG II or proinflammatory cytokines through upregulation of the brain RAS, oxidative stress, and inflammation. NEW & NOTEWORTHY The results of our study indicate that a maternal high-fat diet during either pregnancy or lactation is sufficient for perinatal programming of sensitization for hypertension, which is associated with hyperreactivity of central cardiovascular nuclei that, in all likelihood, involves elevated expression of the renin-angiotensin system, NADPH oxidase, and proinflammatory cytokines. The present study demonstrates, for the first time, the central mechanism underlying maternal high-fat diet sensitization of the hypertensive response in adult offspring.
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Angiotensina II , Fenómenos Fisiológicos Nutricionales de los Animales , Barorreflejo , Presión Sanguínea , Encéfalo/fisiopatología , Dieta Alta en Grasa/efectos adversos , Corazón/inervación , Hipertensión/fisiopatología , Fenómenos Fisiologicos Nutricionales Maternos , Efectos Tardíos de la Exposición Prenatal , Animales , Encéfalo/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Hipertensión/inducido químicamente , Hipertensión/genética , Hipertensión/metabolismo , Mediadores de Inflamación/metabolismo , Masculino , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Estado Nutricional , Estrés Oxidativo , Embarazo , Ratas Sprague-Dawley , Sistema Renina-Angiotensina , VasoconstricciónRESUMEN
A Co-MOF, [Co3(HL)2·4DMF·4H2O] was simply synthesized through a one-pot solvothermal method. With the semiconductor nature, its band gap was determined to be 2.95 eV by the Kubelka-Munk method. It is the first trinuclear Co-MOF employed for photocatalytic hydrogen evolution and CO2 reduction with cobalt-oxygen clusters as catalytic nodes. Hydrogen evolution experiments indicated the activity was related to the photosensitizer, TEOA, solvents, and size of catalyst. After optimization, the best activity of H2 production was 1102 µmol/(g h) when catalyst was ground and then soaked in photosensitizer solution before photoreaction. To display the integrated design of Co-MOF, we used no additional photosensitizer and cocatalyst in the CO2 reduction system. When -NH2 was used for light absorption and a Co-O cluster was used as catalyst, Co-MOF exhibited an activity of 456.0 µmol/(g h). The photocatalytic mechanisms for hydrogen evolution and CO2 reduction were also proposed.
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A robust Zr-MOF (LIFM-28) containing replaceable coordination sites for additional spacer installation has been employed to demonstrate a swing- or multirole strategy for multifunctional MOFs. Through reversible installation/uninstallation of two types of spacers with different lengths and variable functional groups, different tasks can be accomplished using the same parent MOF. An orthogonal optimizing method is applied with seven shorter (L1-7) and six longer (L8-13) spacers to tune the functionalities, achieving multipurpose switches among gas separation, catalysis, click reaction, luminescence, and particularly, ultrahigh methane storage working capacity at 5-80 bar and 298 K.
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A 3D porous perchlorinated metal-organic framework (MOF), LIFM-26, featuring dual functionality, that is, functional polar groups and open metal sites, has been synthesized using perchlorinated linear dicarboxylate to link trigonal prismatic Fe3 (µ3 -O) units. LIFM-26 exhibits good thermal and chemical stability, and possesses high porosity with a BET surface area of 1513â m2 g-1 , compared with isoreticular MOF-235 and Fe3 O(F4 BDC)3 (H2 O)3 (F4 BDC=2,3,5,6-tetrafluorobenzene-1,4-dicarboxylate). Most strikingly, LIFM-26 features good gas sorption/separation performance at 298â K and 1â atm with IAST selectivity values reaching up to 36, 93, 23, 11, 46, and 202 for CO2 /CH4 , CO2 /N2 , C2 H4 /CH4 , C2 H6 /CH4 , C3 H8 /CH4 , and R22/N2 (R22=CHClF2 ), respectively, showing potential for use in biogas/natural gas purification and CO2 /R22 capture.
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Two analogous M4 L4 -type tetrahedral cages (smaller: MOC-19; larger: MOC-22) were synthesized and investigated for their interactions with the anticancer drug 5-fluoracil (5-FU) by NMR spectroscopy, high-resolution electrospray-ionization mass spectrometry (HR-ESI-MS), and molecular simulation. The cage's size and window are of importance for the host-guest binding, and consequently the smaller MOC-19 with a more suitable size of cavity window was found to have much stronger hydrogen-bond interactions with 5-FU. The porous nanoparticles of MOC-19 exhibited outstanding behavior for the controlled release of 5-FU in a simulated human body with liquid phosphate-buffered saline solution.
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Antineoplásicos/administración & dosificación , Preparaciones de Acción Retardada/química , Fluorouracilo/administración & dosificación , Estructuras Metalorgánicas/química , Antineoplásicos/química , Fluorouracilo/química , Enlace de Hidrógeno , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Nanopartículas/química , Tamaño de la Partícula , Porosidad , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
C-X-C motif chemokine receptor 4 (CXCR4) overexpression promotes gastric cancer growth and metastasis. In this study, we determined its role in regulating tumor angiogenesis. We overexpressed CXCR4 in gastric cancer cells and examined the effects of conditioned medium on endothelial cell proliferation, migration, and tube formation. The effects of CXCR4 overexpression on vascular endothelial growth factor (VEGF) expression and signal transducer and activator of transcription 3 (STAT3) activation were analyzed. In vivo xenograft studies were done to confirm the role of CXCR4 in tumor angiogenesis. Conditioned medium from CXCR4-overexpressing gastric cancer cells stimulated endothelial cell proliferation, migration, and tube formation. Such effects were blocked by addition of a neutralizing anti-VEGF antibody. CXCR4 induced VEGF production and JAK2/STAT3 activation and enhanced STAT3 binding to VEGF promoter in gastric cancer cells. Delivery of a dominant negative variant of STAT3 significantly impaired CXCR4-induced upregulation of VEGF. Overexpression of CXCR4 facilitated tumor growth and angiogenesis in SGC7901 xenograft tumors, which was associated with increased levels of phospho-STAT3. CXCR4 contributes to tumor angiogenesis in gastric cancer by inducing STAT3-dependent VEGF expression and represents a promising therapeutic target for this malignancy.
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Janus Quinasa 2/metabolismo , Receptores CXCR4/metabolismo , Factor de Transcripción STAT3/metabolismo , Neoplasias Gástricas/irrigación sanguínea , Animales , Línea Celular Tumoral , Proliferación Celular/fisiología , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Regiones Promotoras Genéticas , Receptores CXCR4/biosíntesis , Receptores CXCR4/genética , Transducción de Señal , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Core-shell or striped heteroatomic lanthanide metal-organic framework hierarchical single crystals were obtained by liquid-phase anisotropic epitaxial growth, maintaining identical periodic organization while simultaneously exhibiting spatially segregated structure. Different types of domain and orientation-controlled multicolor photophysical models are presented, which show either visually distinguishable or visible/near infrared (NIR) emissive colors. This provides a new bottom-up strategy toward the design of hierarchical molecular systems, offering high-throughput and multiplexed luminescence color tunability and readability. The unique capability of combining spectroscopic coding with 3D (three-dimensional) microscale spatial coding is established, providing potential applications in anti-counterfeiting, color barcoding, and other types of integrated and miniaturized optoelectronic materials and devices.
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A sacrificial template strategy is developed for the synthesis of yolk-shell Au@ZIF-8 nanoreactor. The Au@ZIF-8 nanoreactor possesses single-crystalline metal-organic framework (MOF) shell with intrinsic monodisperse micropores and introduced macropores. In each of the macropores, one Au NP is encapsulated to form a nanoreactor unit. The quantity of the reactor units in the MOF shell can be readily regulated. Such structure features of the Au@ZIF-8 nanoreactor facilitate the size selectivity of reactants, the accessibility of Au nanoparticles to reactants, and the mass transfer of reactants and products. As a result, the Au@ZIF-8 nanoreactor delivers excellent size selectivity, enhanced conversion, and good cycling stability when used to catalyze the aerobic oxidation of alcohols with different molecular size.