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Synthetic membranes featuring confined nanostructures have emerged as a prominent category of leading materials that can selectively separate target ions from complex water matrices. Further advancements in these membranes will pressingly rely on the ability to elucidate the inherent connection between transmembrane ion permeation behaviors and the ion-selective nanostructures. In this review, we first abstract state-of-the-art nanostructures with a diversity of spatial confinements in current synthetic membranes. Next, the underlying mechanisms that govern ion permeation under the spatial nanoconfinement are analyzed. We then proceed to assess ion-selective membrane materials with a focus on their structural merits that allow ultrahigh selectivity for a wide range of monovalent and divalent ions. We also highlight recent advancements in experimental methodologies for measuring ionic permeability, hydration numbers, and energy barriers to transport. We conclude by putting forth the future research prospects and challenges in the realm of high-performance ion-selective membranes.
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BACKGROUND: Lymphangiomas in the gastrointestinal tract are extremely rare in adults. As a benign lesion, small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis. However, lymphangiomas can give rise to complications such as abdominal pain, bleeding, volvulus, and intussusception. Here, we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male adult. CASE SUMMARY: A 66-year-old man presented with intermittent melena, fatigue and refractory anemia nine months prior. Esophagogastroduodenoscopy and colonoscopy were performed many times and revealed no apparent bleeding. Conservative management, including transfusion, hemostasis, gastric acid secretion inhibition and symptomatic treatment, was performed, but the lesions tended to recur shortly after surgery. Ultimately, the patient underwent capsule endoscopy, which revealed a more than 10 cm lesion accompanied by active bleeding. After single-balloon enteroscopy and biopsy, a diagnosis of jejunal cavernous lymphangioma was confirmed, and the patient underwent surgical resection. No complications or recurrences were observed postoperatively. CONCLUSION: Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal bleeding. Capsule endoscopy and single-balloon enteroscopy can facilitate diagnosis. Surgical resection is an effective management method.
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Aim: This study aimed to develop a sonodynamic-chemodynamic nanoparticle functioning on glutathione depletion in tumor immunotherapy. Materials & methods: The liposome-encapsulated 2,2-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIPH) and copper-cysteine nanoparticles, AIPH/Cu-Cys@Lipo, were synthesized with a one-pot method. 4T1 cells were injected into female BALB/c mice for modeling. Results: AIPH/Cu-Cys@Lipo was well synthesized. It generated alkyl radicals upon ultrasound stimulation. AIPH/Cu-Cys@Lipo promoted the generation of -OH via a Fenton-like reaction. Both in vitro and in vivo experiments verified that AIPH/Cu-Cys@Lipo significantly inhibited tumor development by decreasing mitochondrial membrane potential, activating CD4+ and CD8+ T cells and promoting the expression of IL-2 and TNF-α. Conclusion: AIPH/Cu-Cys@Lipo provides high-quality strategies for safe and effective tumor immunotherapy.
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Nanopartículas Multifuncionais , Nanopartículas , Neoplasias , Feminino , Animais , Camundongos , Linfócitos T CD8-Positivos , Cobre , Cisteína , Glutationa , Imunoterapia , Camundongos Endogâmicos BALB C , Linhagem Celular Tumoral , Microambiente Tumoral , Peróxido de HidrogênioRESUMO
Single-atom catalysts have become a popular choice in various catalysis applications, as they take advantages of both homogeneous catalysis (e.g., high efficiency) and heterogeneous catalysis (e.g., easy catalyst recovery). The atom support plays an indispensable role in anchoring atomic species and interplaying with them for ultimate catalytic performance. Therefore, development of new support materials for superior catalysis is of great importance. Here the synthesis of carbon nanofibers based on the reaction between phosphorus pentoxide (P2 O5 ) and N-methyl-2-pyrrolidone (NMP) is reported. The underlying reaction process is systematically investigated by Fourier-transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. The carbon nanofibers have interesting PN units in their chemical structure, which act as anchoring sites for the single-atom catalyst. The Pt atoms anchoring carbon nanofibers exhibit high activity for hydrosilylation with a turnover frequency (TOF) of 9.2 × 106 h-1 and a selectivity of >99%. This research affords not only a new in situ chemical strategy to synthesize multiatom doped carbon nanofibers but also presents a potential superior support in catalysis, which opens a hopeful window in materials chemistry and catalysis applications.
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We report a facile strategy for synthesizing uniform heterometallic bi/tri-atom clusters starting from mono-metallic atoms in the liquid phase. Specifically, Pt1,2Cu bi/tri-atoms are prepared by reducing CuCl2 at preformed Pt1 atoms with ethanol inside a PDMS-PEG protective layer. The metal atoms in the Pt1,2Cu clusters are in reduced chemical states.
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The hydrosilylation reaction is one of the largest-scale applications of homogeneous catalysis, and Pt homogeneous catalysts have been widely used in this reaction for the commercial manufacture of silicon products. However, homogeneous Pt catalysts result in considerable problems, such as undesired side reactions, unacceptable catalyst residues and disposable platinum consumption. Here, we synthesized electron-deficient Pt single atoms supported on humic matter (Pt1 @AHA_U_400), and the catalyst was used in hydrosilylation reactions, which showed super activity (turnover frequency as high as 3.0×107 â h-1 ) and selectivity (>99 %). Density functional theory calculations reveal that the high performance of the catalyst results from the atomic dispersion of Pt and the electron deficiency of the Pt1 atoms, which is different from conventional Pt nanoscale catalysts. Excellent performance is maintained during recycle experiments, indicating the high stability of the catalyst.
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BACKGROUND: The pathogenesis of Severe Acute Pancreatitis (SAP) is mediated substantially by dysfunctions in the intestinal barrier. Euphorbia kansui (EK) is a medicinal plant used widely in traditional Chinese medicine to treat inflammation; however, its efficacy and mechanism of action in SAP treatment are not yet well understood. OBJECTIVE: To investigate the role of EK in intestinal barrier tissue repair and in the pathogenesis and development of SAP. METHODS: The rat SAP model was established by a retrograde injection of sodium taurocholate into the pancreatic bile duct. The SAP model group and the SAP + EK treatment groups were divided into 6 subgroups according to timing: 2, 6, 12, 24, 48, or 72h after inducing SAP. The progression of the SAP rats and of the rats receiving the EK treatment was evaluated using the ascites volume, serum amylase and plasma endotoxin levels, and histological grading of intestinal mucosal damage. In addition, serum inflammatory factor contents were measured using Enzyme-Linked Immunosorbent Assay (ELISA) tests and apoptotic cells in damaged ileum tissue were detected using TUNEL staining. Apoptosis markers and other signaling proteins in intestinal mucosal cells were detected by immunohistochemical assays and then validated by combining these data with quantitative polymerase chain reactions and western blotting. RESULTS: Compared with the results of the SAP model rats, the results of the rats that received EK treatment demonstrated that EK could effectively reduce the ascites volume and serum amylase and plasma endotoxin levels. EK treatment also greatly reduced the abnormal intestinal morphological alterations in the rat SAP model and significantly downregulated the serum contents of Interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α. EK treatment inhibited the elevation of capapse-3, inhibited the decrease of the Bcl-2 protein, and decreased the number of apoptotic cells in rat ileum tissue. Finally, EK treatment abrogated the increase of HMGB1 and the suppression of MFG-E8 protein expression in the SAP + EK rat ileum tissue. CONCLUSION: EK suppresses SAP pathogenesis by restoring the intestinal barrier function and modulating the HMGB1/MFG-E8 signaling axis.
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Euphorbia , Proteína HMGB1 , Pancreatite , Doença Aguda , Animais , Mucosa Intestinal , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Ratos , Ratos Sprague-DawleyRESUMO
Overexpression of the tumor necrosis factor receptor-associated factor 4 (TRAF4) has been detected in many cancer types and is considered to foster tumor progression. However, the role of TRAF4 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that TRAF4 was highly expressed in HCC cell lines and HCC tissues compared with normal liver cell lines and adjacent noncancerous tissues. TRAF4 overexpression in HCC tissues was correlated with tumor quantity and vascular invasion. In vitro studies showed that TRAF4 was associated with HCC cell migration and invasion. An in vivo study verified that TRAF4 overexpression facilitated metastasis in nude mice. In addition, overexpressed TRAF4 promoted the phosphorylation of Akt and induced Slug overexpression, leading to downregulated E-cadherin and upregulated vimentin, while silencing TRAF4 moderated the phosphorylation of Akt and repressed the expression of Slug, which resulted in upregulated E-cadherin and downregulated vimentin. These effects were inversed after pretreatment of the PI3K/Akt inhibitor LY294002 or overexpression of constitutively active Akt1. Our study demonstrated that TRAF4 was involved in promoting HCC cell migration and invasion. The process was induced by the EMT through activation of the PI3K/Akt signaling pathway.
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BACKGROUND: Oridonin is the core bioactive component of Rabdosia rubescens, a traditional Chinese herbal medicine used in the treatment of hepatoma. Sorafenib, a targeted therapeutic agent for advanced hepatocellular carcinoma (HCC), has recently been shown to exert limited clinical effects. However, few studies have focused on the synergistic effect of these two drugs on hepatocellular carcinoma. METHODS: We treated different HCC cell lines with different concentrations of oridonin and sorafenib and assessed the viability by using MTT assays and examined proliferation, migration, invasion and apoptosis after cotreatment of HepG2 cells with 20 µM oridonin and 5 µM sorafenib via colony formation assays, Transwell assays and flow cytometry. Regulatory effects were measured by Western blotting. The in vivo synergistic effect was confirmed through xenograft tumor models, and tumor tissues were analyzed by immunohistochemistry. RESULTS: The inhibitory effects of oridonin and sorafenib cotreatment on HCC cells were stronger than those of either drug alone. In addition, combined treatment with the two drugs synergistically inhibited epithelial-mesenchymal transition and the Akt pathway but not NF-κB or MAPK signaling. Akt phosphorylation by SC79 reversed the inhibitory effects of the combined treatment. Synergistic inhibition was equally observed in vivo. CONCLUSION: Oridonin combined with sorafenib synergistically inhibited proliferation, migration, invasion, and epithelial-mesenchymal transition and induced apoptosis by targeting the Akt pathway but not NF-κB or MAPK signaling.
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BACKGROUND: Bisdemethoxycurcumin (BDMC), a stable bioactive ingredient in curcuminoids, is associated with various antitumor functions, such as proliferation inhibition, metastasis suppression and apoptosis induction, in many cancer types. However, the mechanism of BDMC in hepatocellular carcinoma (HCC) remains unclear. METHODS: We assessed the toxicity and the inhibitory effect of BDMC in the HepG2 cell line by using CCK-8 and colony formation assays. The regulatory effects of BDMC on Akt and MAPK signaling were investigated by Western blotting and immunoprecipitation. RESULTS: We found that the half-maximum inhibitory concentration (IC50) of BDMC after 48 hrs of treatment was 59.13 µM, and BDMC inhibited proliferation in a time- and dose-dependent manner in HepG2 cells. The inhibitory effect was caused by the inactivation of Akt signaling, but not Erk, Jnk or p38 signaling. In addition, the inactivation of Akt signaling was attributed to the inhibition of ubiquitination mediated by K63-Ub but not K48-Ub. Furthermore, we found that BDMC upregulated the expression of CYLD, leading to Akt deubiquitination and inactivation. CONCLUSION: BDMC inhibited HCC cell proliferation, and that this effect was induced by Akt inactivation via CYLD-mediated deubiquitination.
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Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Enzima Desubiquitinante CYLD/metabolismo , Diarileptanoides/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Estrutura Molecular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
While numerous single atoms stabilized by support surfaces have been reported, the synthesis of in-situ reduced discrete metal atoms weakly coordinated and stabilized in liquid media is a more challenging goal. We report the genesis of mononuclear electron deficient Pt1(0) by reducing H2PtCl6 in liquid polydimethylsiloxane-polyethylene glycol (PDMS-PEG) (Pt1@PDMS-PEG). UV-Vis, far-IR, and X-ray photoelectron spectroscopies evidence the reduction of H2PtCl6. CO infrared, and 195Pt and 13C NMR spectroscopies provide strong evidence of Pt1(0), existing as a pseudo-octahedral structure of (R1OR2)2Pt(0)Cl2H2 (R1 and R2 are H, C, or Si groups accordingly). The weakly coordinated (R1OR2)2Pt(0)Cl2H2 structure and electron deficient Pt1(0) have been validated by comparing experimental and DFT calculated 195Pt NMR spectra. The H+ in protic state and the Cl- together resemble HCl as the weak coordination. Neutralization by a base causes the formation of Pt nanoparticles. The Pt1@PDMS-PEG shows ultrahigh activity in olefin hydrosilylation with excellent terminal adducts selectivity.
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BACKGROUND: Liver re-resection plays a paramount role in treatment of patients with posthepatectomy hepatocellular carcinoma (HCC) recurrence. Laparoscopic liver resection has been a feasible alternative to open surgery. However, whether laparoscopic liver re-resection for posthepatectomy HCC recurrence is better than open liver re-resection remains unknown. METHOD: From January 2008 to December 2015, 30 patients with recurrent HCC after prior liver resection underwent laparoscopic liver re-resection in our center. To minimize any confounding factors, a propensity score matching study using a patient ratio of 1:1 was conducted to compare the short- and long-term outcomes of patients who underwent laparoscopic or open liver re-resection. RESULT: With the open surgery group compared laparoscopic group, operative time was 207.50 versus 200.5 min (p = 0.903), blood loss was 400 versus 100 ml (p = 0.000196), blood transfusion rate was 43.3 versus 0.0% (p = 0.000046), complication rates were 30.0 versus 6.7% (p = 0.01), and hospital stay was 13.5 versus 9.5 days (p = 0.000008). The median follow-up was 35 months. The 1-year, 3-year, 5-year disease-free survival rates were 79.0, 51.0, and 31.9%, versus 78.3, 57.4, and 43.0%, respectively (p = 0.474). The 1-year, 3-year, and 5-year overall survival rates were 89.4, 75, and 67.5%, versus 96.7, 85.0, and 74.4%, respectively (p = 0.413). CONCLUSION: Laparoscopic liver re-resection for patients with posthepatectomy HCC recurrence provided comparable perioperative and oncological outcomes as open liver re-resection and can be a safe alternative to open procedure.
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Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/cirurgia , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , China , Intervalo Livre de Doença , Feminino , Hepatectomia/métodos , Humanos , Laparoscopia/métodos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Pontuação de Propensão , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Overexpression of the tumor necrosis factor receptor-associated factor 4 (TRAF4) has been detected in many cancer types and is considered to foster tumor progression. However, the role of TRAF4 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that TRAF4 was highly expressed in HCC cell lines and HCC tissues compared with normal liver cell lines and adjacent noncancerous tissues. TRAF4 overexpression in HCC tissues was correlated with tumor quantity and vascular invasion. In vitro studies showed that TRAF4 was associated with HCC cell migration and invasion. An in vivo study verified that TRAF4 overexpression facilitated metastasis in nude mice. In addition, overexpressed TRAF4 promoted the phosphorylation of Akt and induced Slug overexpression, leading to downregulated E-cadherin and upregulated vimentin, while silencing TRAF4 moderated the phosphorylation of Akt and repressed the expression of Slug, which resulted in upregulated E-cadherin and downregulated vimentin. These effects were inversed after pretreatment of the PI3K/Akt inhibitor LY294002 or overexpression of constitutively active Akt1. Our study demonstrated that TRAF4 was involved in promoting HCC cell migration and invasion. The process was induced by the EMT through activation of the PI3K/Akt signaling pathway.
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Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator 4 Associado a Receptor de TNF/genética , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Transição Epitelial-Mesenquimal , Células Hep G2 , Xenoenxertos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Transdução de Sinais , Fator 4 Associado a Receptor de TNF/biossíntese , Fator 4 Associado a Receptor de TNF/metabolismoRESUMO
Sorafenib has been globally approved as the standard treatment for patients with advanced hepatocellular carcinoma (HCC). However, the response rate of HCC patients to sorafenib is limited because of tumor recurrence and metastasis. Therefore, seeking combined therapeutic strategies with sorafenib is necessary to improve the antitumor efficiency. Here we demonstrated that expression of MMP-2 is positively correlated with the migration ability of HCC cells. Cells with a higher MMP-2 expression (SK-HEP-1 cells) were less sensitive to sorafenib than those with lower MMP-2 expression (HepG2 cells). Cotreatment of cells with SB-3CT and sorafenib more strongly inhibited migration ability than with sorafenib treatment alone in both HCC cells with high and low expression of MMP-2. In vivo cell metastasis experiments confirmed the synergistic effects of sorafenib and SB-3CT in reducing lung metastasis of SK-HEP-1 cells. Mechanistically, we showed that the synergistic antitumor effect may be attributed to inhibition of the PI3K/AKT/mTOR signaling pathway, but not the RAF/MEK/ERK signaling pathway. With these results taken together, the current study demonstrates that inhibiting MMP-2 expression can enhance the antitumor effect of sorafenib in HCC cells with a high MMP-2 expression, which may provide a novel strategy to improve therapeutic efficiency in HCC.
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Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Inibidores de Metaloproteinases de Matriz/farmacologia , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Animais , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metaloproteinase 2 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/administração & dosagem , Camundongos , Camundongos Nus , Niacinamida/administração & dosagem , Niacinamida/farmacologia , Compostos de Fenilureia/administração & dosagem , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sorafenibe , Serina-Treonina Quinases TOR/metabolismoRESUMO
We report the synthesis of bis(hydroxylmethylfurfuryl)amine (BHMFA) from 5-hydroxymethylfurfural (5-HMF) by reacting 5-HMF with primary amines in the presence of homogeneous Ru(II) catalysts having sterically strained ligands. BHMFA is a group of furan-based monomers that offer great potential to form functional biopolymers with tunable properties. A range of primary amines, such as aliphatic and benzyl amines, are readily converted with 5-HMF to form the corresponding BHMFA in good yields. The reaction proceeds through reductive amination of 5-HMF with primary amine to form secondary amine, followed by reductive amination of 5-HMF with inâ situ generated secondary amine to produce BHMFA.