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1.
Dig Dis Sci ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009916

RESUMO

BACKGROUND: Rectal indomethacin reduces pancreatitis following endoscopic retrograde cholangiopancreatography (ERCP). However, there is insufficient evidence regarding its added benefits in patients already receiving prophylactic pancreatic stenting. Our goal was to evaluate the impact of indomethacin in high-risk patients undergoing pancreatic stenting. METHODS: A cohort study was conducted on all patients who underwent the rescue cannulation technique for challenging bile duct cannulation (selected high-risk patients). Patients were split into two groups based on the prophylaxis method for post-ERCP pancreatitis (PEP): one receiving a combination of indomethacin and pancreatic stenting, while the other received pancreatic stenting alone. Comparative analyses were carried out on PEP, hyperamylasemia, gastrointestinal bleeding, and postoperative hospital stay among post-ERCP pancreatitis patients. RESULTS: Between November 2017 and May 2023, a total of 607 patients with native papillae were enrolled, with 140 grouped into the indomethacin plus stent group and 467 into the stent alone group. The overall PEP rate was 4.4% in the entire cohort, with no statistical differences observed between the groups in terms of PEP rates (P = 0.407), mild PEP (P = 0.340), moderate to severe PEP (P = 1.000), hyperamylasemia (P = 0.543), gastrointestinal bleeding (P = 0.392), and postoperative hospital stay (P = 0.521). Furthermore, sensitivity analysis using multivariable analysis also validated these findings. CONCLUSIONS: Indomethacin did not reduce the incidence or severity of PEP in high-risk patients who routinely received prophylactic pancreatic stent placement. Therefore, the additional administration of rectal indomethacin to further mitigate PEP appears to be not necessary.

2.
Dig Dis Sci ; 69(6): 2215-2222, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38594433

RESUMO

BACKGROUND: When unintentional pancreatic duct access occurs during difficult biliary cannulation, the double guidewire (DGW) or transpancreatic sphincterotomy (TPS) may be utilized. DGW can be easily switched to TPS due to the existing guidewire in the pancreatic duct. However, the efficacy of TPS after DGW, named sequential DGW-TPS technique, versus primary TPS has not been assessed. AIMS: Our aim was to compare the benefits and adverse events of sequential DGW-TPS technique and primary TPS. METHODS: We performed a comparative retrospective cohort study that enrolled a total of 117 patients with native papillae. The patients were divided into one of 2 groups according to the primary bile duct access technique (sequential DGW-TPS or primary TPS), both with pancreatic stenting. RESULTS: Between November 2017 and May 2023, a total of 84 patients were grouped into sequential DGW-TPS and 33 into primary TPS. The overall post-ERCP pancreatitis (PEP) rate was 4.3% in the entire cohort, with no statistical differences were observed between the groups in terms of PEP rates (P = 0.927), PEP severity (P = 1.000), first biliary cannulation success (P = 0.621), overall cannulation success (P = 1.000), hyperamylasemia incidence (P = 0.241), elevated amylase levels (P = 0.881), and postoperative hospital stay (P = 0.185). Furthermore, these results remained consistent in multivariable regression analysis. CONCLUSIONS: The sequential DGW-TPS technique showed a comparable safety and biliary cannulation success rate to primary TPS in difficult biliary cannulation. Given the potential long-term complications associated with TPS, DGW should be first if inadvertent pancreatic access occurs, with TPS serving as second only if DGW fails.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Ductos Pancreáticos , Pancreatite , Esfinterotomia Endoscópica , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Esfinterotomia Endoscópica/métodos , Esfinterotomia Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Pancreatite/etiologia , Pancreatite/epidemiologia , Ductos Pancreáticos/cirurgia , Cateterismo/métodos , Cateterismo/efeitos adversos , Cateterismo/instrumentação , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Stents , Adulto
3.
Environ Res ; 237(Pt 1): 116987, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37633636

RESUMO

Efficiently addressing initial rainwater pollution is crucial for mitigating urban water pollution. However, the performance evaluation of initial rainwater pollution control project is rarely introduced. In this study, the architecture of effective comprehensive engineering measures for improving the water quality of initial rainwater in Anhui Province, China, was described. Three water quality indicators, ammonia nitrogen (NH3-N), chemical oxygen demand (COD), and total phosphorus (TP), were selected to explore the severity of urban pollution caused by initial rainwater under various rainfall scenarios. A single-factor evaluation method was used to contrast and assess the benefits of the initial rainfall interception project in terms of water quality enhancement. Results showed that initial rainfall pollution was gentler under light rainfall conditions but more prominent under moderate and heavy conditions. The percentages of NH3-N, COD, and TP in Lotus Pond that met the tertiary drinking water standard were 100%, 74.91%, and 100% with great improvement, and the average concentrations of NH3-N, COD, and TP in Fushan Road Drainage have decreased by 91.43%, 10.49%, and 57.33% respectively, after the construction of the interception project. These indicated that the nitrogen and phosphorus pollution were successfully controlled by the control techniques in both locations, but COD concentration has to be addressed with more specialized strategies. Overall, the water quality improvement project for initial rainwater pollution plays a great role in effectively governing initial rainwater pollution and improving river water quality, and provides an effective technical reference for urban water ecological environment management.

4.
Int J Mol Sci ; 24(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37510993

RESUMO

Immunotherapies including adaptive immune checkpoint inhibitors (ICIs) and chimeric antigen receptor (CAR) T cells, have developed the treatment of cancer in clinic, and most of them focus on activating T cell immunity. Although these strategies have obtained unprecedented clinical responses, only limited subsets of cancer patients could receive long-term benefits, highlighting the demand for identifying novel targets for the new era of tumor immunotherapy. Innate immunity has been demonstrated to play a determinative role in the tumor microenvironment (TME) and influence the clinical outcomes of tumor patients. A thorough comprehension of the innate immune cells that infiltrate tumors would allow for the development of new therapeutics. In this review, we outline the role and mechanism of innate immunity in TME. Moreover, we discuss innate immunity-based cancer immunotherapy in basic and clinical studies. Finally, we summarize the challenges in sufficiently motivating innate immune responses and the corresponding strategies and measures to improve anti-tumor efficacy. This review could aid the comprehension of innate immunity and inspire the creation of brand-new immunotherapies for the treatment of cancer.


Assuntos
Neoplasias , Humanos , Neoplasias/patologia , Imunidade Inata , Imunoterapia , Linfócitos T , Biologia , Microambiente Tumoral
5.
Plant Physiol ; 187(4): 2296-2310, 2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34601582

RESUMO

AKT2 potassium (K+) channels are members of the plant Shaker family which mediate dual-directional K+ transport with weak voltage-dependency. Here we show that OsAKT2 of rice (Oryza sativa) functions mainly as an inward rectifier with strong voltage-dependency and acutely suppressed outward activity. This is attributed to the presence of a unique K191 residue in the S4 domain. The typical bi-directional leak-like property was restored by a single K191R mutation, indicating that this functional distinction is an intrinsic characteristic of OsAKT2. Furthermore, the opposite R195K mutation of AtAKT2 changed the channel to an inward-rectifier similar to OsAKT2. OsAKT2 was modulated by OsCBL1/OsCIPK23, evoking the outward activity and diminishing the inward current. The physiological relevance in relation to the rectification diversity of OsAKT2 was addressed by functional assembly in the Arabidopsis (Arabidopsis thaliana) akt2 mutant. Overexpression (OE) of OsAKT2 complemented the K+ deficiency in the phloem sap and leaves of the mutant plants but did not significantly contribute to the transport of sugars. However, the expression of OsAKT2-K191R overcame both the shortage of phloem K+ and sucrose of the akt2 mutant, which was comparable to the effects of the OE of AtAKT2, while the expression of the inward mutation AtAKT2-R195K resembled the effects of OsAKT2. Additionally, OE of OsAKT2 ameliorated the salt tolerance of Arabidopsis.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Oryza/genética , Oryza/metabolismo , Floema/metabolismo , Canais de Potássio/metabolismo , Tolerância ao Sal/fisiologia , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Mutação , Floema/genética , Canais de Potássio/genética , Tolerância ao Sal/genética
6.
Chem Soc Rev ; 49(4): 1071-1089, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31971530

RESUMO

Two-dimensional (2D) nanosheets have emerged as promising functional materials owing to their atomic thickness and unique physical/chemical properties. By using 2D nanosheets as building blocks, diverse kinds of two-dimensional nanochannel membranes (2DNCMs) are being actively explored, in which mass transport occurs in the through-plane and interlayer channels of 2D nanosheets. The rational construction and physical/chemical microenvironment regulation of nanochannels are of vital significance for translating these 2D nanosheets into molecular separation membranes and ionic separation membranes. Focusing on the recent advances of 2DNCMs, in this review, various porous/nonporous 2D nanosheets and their derived nanochannels are first briefly introduced. Then we discuss the emerging top-down and bottom-up methods to synthesize high-quality 2D nanosheets and to prepare high-performance 2DNCMs. As the major part of this review, we focus on three types of nanochannels, which are based on nonporous nanosheets, intrinsically porous nanosheets and perforated nanosheets. The strategies for regulating the physical and chemical microenvironments in the nanochannels are emphasized. The representative applications of 2DNCMs in molecular separations (gas separation, liquid separation) and ionic separations are presented. Finally, the current challenges and future perspectives are highlighted.

7.
Opt Express ; 28(14): 19877-19886, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32680058

RESUMO

We present an in-depth investigation of optical rogue waves (ORWs) during picosecond supercontinuum generations in photonic crystal fibers with periodic landscapes of group velocity dispersion and nonlinearity, namely dispersion oscillating fibers (DOFs). Specifically, it is shown via ensembles of numerical simulations that during supercontinuum generations, the rogue nature of extreme and rare events formed in uniform fibers can be effectively manipulated in DOFs. This is also verified by comparing single evolution dynamics in different dispersion longitudinal profiles. For investigating the influence of slow dynamics of ORW generation in DOFs, we increase the propagating distance and find out MI gain is still the major factor that influences the generation of ORWs. In addition, analytical results associated with simulations indicate the rogue manipulations in DOFs are attributed to the adjustable modulation-instability-gain due to periodic dispersion variation along fiber length. Finally, unlike MI in uniform fiber, MI gain side lobes result from quasi-phase-matching (QPM) relation in DOFs provide additional degree of freedom to control generations of ORWs. We believe our results will provide not only a novel insight of understanding ORW dynamics in presence of dispersion modulations, but also a new way of harnessing rogue waves in oceanology.

8.
Inorg Chem ; 59(7): 4435-4442, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32167757

RESUMO

Two novel thorium-based metal-organic frameworks (MOFs), namely Th-SINAP-7 and Th-SINAP-8, have been synthesized via the solvothermal reactions of thorium nitrate and 1,4- or 2,6-naphthalenedicarboxylic acid in the presence of acid modulators. Bearing the rigid aromatic architectures, Th-SINAP-7 and Th-SINAP-8 exhibit exceptional chemical (from pH 1 to 12) and thermal stabilities (up to 520 °C), as well as ionizing radioresistance (2 × 105 Gy ß and γ irradiations). The highly porous nature and conjugated π-electrons of naphthalene on the organic linkers endow high affinity of both MOFs toward I2 molecules owning to the charge transfer between π-electrons of the host networks and the guest iodine molecules, as evidenced by combined techniques including of FTIR, PXRD, SEM-EDS, UV-vis spectroscopy, XPS, and Raman spectroscopy. Particularly, Th-SINAP-8 can efficiently remove >99% I2 from cyclohexane solution and exhibit guest uptake of iodine vapor with an adsorption capacity of 473 mg/g.

9.
Appl Microbiol Biotechnol ; 103(12): 4825-4838, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31053913

RESUMO

Arginase I has been documented to impair T cell function and attenuate cellular immunity, however, there is little evidence to reveal the effect of arginase I on macrophage function. Recently, recombinant human arginase I (rhArg) has been developed for cancer therapy and is in clinical trial for hepatocellular carcinoma, whereas the potential immunosuppression induced by rhArg limited its therapeutic efficacy. To improve the clinical outcome of rhArg, addressing the immune suppression appears to be particularly important. In this study, we found that rhArg attenuated macrophage functions, including inhibiting macrophage cell proliferation, nitric oxide (NO) and reactive oxygen species (ROS) production, cytokine secretion, MHC-II surface expression, and phagocytosis, thereby inducing immunosuppression in lipopolysaccharides (LPS)/interferon-γ (IFN-γ)-activated macrophages. Notably, we observed that rhArg downregulated autophagy in activated macrophages. Moreover, application of trehalose (an autophagy inducer) significantly restored the impaired immune function in activated macrophages, suggesting the essential role of autophagy in rhArg-induced immunosuppression. To further illustrate the effect of autophagy in immunosuppression, we then observed the effect of 3-MA (an autophagy inhibitor) on the immune function of macrophages. As expected, inhibiting autophagy by 3-MA attenuated immune functions in activated macrophages. Collectively, this study elucidated that rhArg induced immunosuppression in activated macrophages via inhibiting autophagy, providing potential strategy to ameliorate the immune suppression which is of great significance to cancer therapy and facilitating the development of rhArg as a potential therapy for malignant carcinomas.


Assuntos
Arginase/imunologia , Autofagia/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Imunossupressores/farmacologia , Macrófagos/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Arginase/genética , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Citocinas/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Neoplasias Hepáticas/terapia , Macrófagos/patologia , Camundongos , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/imunologia , Trealose/farmacologia
10.
Mikrochim Acta ; 186(9): 603, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385118

RESUMO

A flexible adhesive tape decorated with SERS-active silver nanorods (AgNRs) in the form of an array nanostructure is described. The tape was constructed by transferring the AgNRs nanostructures from silicon to the transparent tape by a "paste & peel off" procedure. The transparent, sticky, and flexible properties of commercial tapes allow almost any SERS-inactive irregular surface to be detected in-situ by pasting the SERS tape onto the position to be analyzed. Three examples for an analytical application are presented, viz. determination of (a) tetramethylthiuram disulfide and thiabendazole (two pesticides), (b) colorants in the gel of a writing pen, and (c) the fluorophore Rhodamine B. The tetramethylthiuram disulfide on apple surface was rapidly detected with a LOD of 28.8 ng·cm-2. The AgNRs effectively quenched the fluorescence of the matrix and fluorophores, this enabling the colorants and Rhodamine B to be identified. The results demonstrated that the SERS tape can be used for versatile in-situ detection. Conceivably, it may find applications in food analysis, non-invasive identification, environmental monitoring, and in other areas of daily life. Graphic abstract A flexible and adhesive SERS active tape decorated with silver nanorods (AgNRs) arrays was constructed through a "paste & peel off" method. It can be used as a versatile in situ analysis platform for various applications.

11.
Carcinogenesis ; 39(5): 689-699, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29538621

RESUMO

CD47-targeting immune checkpoint inhibitors have been investigated for immunotherapy of several cancers, glioblastoma, one of the most common tumors in brain, was still a challenge for CD47-targeting therapy. Herein, we reported novel strategies for glioblastoma therapy via blocking CD47-signal regulatory protein-α (SIRPα) by SIRPα-Fc alone or in combination with autophagy inhibition. Our results showed that SIRPα-Fc increased macrophages-triggered cytotoxicity and phagocytosis of glioblastoma cells then elicited potent anti-tumor efficacy. During the treatment, SIRPα-Fc induced autophagy and autophagic flux in glioblastoma cells and Akt/mammalian target of rapamycin (mTOR) inactivation was participated in the autophagy activation. Inhibition of autophagy by pharmacological agents or small-interfering RNA increased SIRPα-Fc-triggered macrophage phagocytosis and cytotoxicity. Importantly, when compared with SIRPα-Fc treatment, blocking both CD47/SIRPα and autophagy significantly increased infiltration of macrophages and apoptosis of tumor cells, triggering potentiated anti-glioblastoma effect and extended median survival. Further experiments showed that adaptive immune response, including CD8+ T-cell subsets, was also played a crucial role in SIRPα-Fc-induced glioblastoma rejection. Our results indicated that SIRPα-Fc alone or combined with autophagy inhibitors elicited potent anti-glioblastoma effect, highlighting potential therapeutic strategies of glioblastoma via blocking CD47/SIRPα alone or in combination with autophagy inhibitor.


Assuntos
Autofagia/imunologia , Antígeno CD47/metabolismo , Glioblastoma/metabolismo , Glioblastoma/terapia , Receptores Imunológicos/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Glioblastoma/imunologia , Humanos , Imunoterapia/métodos , Macrófagos/imunologia , Camundongos , Fagocitose/imunologia , Serina-Treonina Quinases TOR/metabolismo
12.
J Am Chem Soc ; 140(1): 250-257, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29250960

RESUMO

Benefiting from extremely high shear modulus and high ionic transference number, solid electrolytes are promising candidates to address both the dendrite-growth and electrolyte-consumption problems inherent to the widely adopted liquid-phase electrolyte batteries. However, solid electrolyte/electrode interfaces present high resistance and complicated morphology, hampering the development of solid-state battery systems, while requiring advanced analysis for rational improvement. Here, we employ an ultrasensitive three-dimensional (3D) chemical analysis to uncover the dynamic formation of interphases at the solid electrolyte/electrode interface. While the formation of interphases widens the electrochemical window, their electronic and ionic conductivities determine the electrochemical performance and have a large influence on dendrite growth. Our results suggest that, contrary to the general understanding, highly stable solid electrolytes with metal anodes in fact promote fast dendritic formation, as a result of less Li consumption and much larger curvature of dendrite tips that leads to an enhanced electric driving force. Detailed thermodynamic analysis shows an interphase with low electronic conductivity, high ionic conductivity, and chemical stability, yet having a dynamic thickness and uniform coverage is needed to prevent dendrite growth. This work provides a paradigm for interphase design to address the dendrite challenge, paving the way for the development of robust, fully operational solid-state batteries.

13.
Biochem Soc Trans ; 46(4): 1003-1012, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30065108

RESUMO

The family of Rho GTPases are involved in the dynamic control of cytoskeleton reorganization and other fundamental cellular functions, including growth, motility, and survival. Rac1, one of the best characterized Rho GTPases, is an established effector of receptors and an important node in signaling networks crucial for tumorigenesis and metastasis. Rac1 hyperactivation is common in human cancer and could be the consequence of overexpression, abnormal upstream inputs, deregulated degradation, and/or anomalous intracellular localization. More recently, cancer-associated gain-of-function mutations in Rac1 have been identified which contribute to tumor phenotypes and confer resistance to targeted therapies. Deregulated expression/activity of Rac guanine nucleotide exchange factors responsible for Rac activation has been largely associated with a metastatic phenotype and drug resistance. Translating our extensive knowledge in Rac pathway biochemistry into a clinical setting still remains a major challenge; nonetheless, remarkable opportunities for cancer therapeutics arise from promising lead compounds targeting Rac and its effectors.


Assuntos
Neoplasias/patologia , Proteínas rac de Ligação ao GTP/metabolismo , Progressão da Doença , Suscetibilidade a Doenças , Humanos , Neoplasias/metabolismo , Transdução de Sinais
14.
Opt Express ; 26(26): 34689-34698, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30650889

RESUMO

A fiber analogue of the optical event horizon is proposed via an Airy-soliton collision. The characteristics of an Airy pulse are demonstrated in a photonic crystal fiber. The robust Airy wave packet is capable of being manipulated by a strong soliton in the frame of the Airy-soliton horizon, leading to various distinctive interaction scenarios. The Airy pulse realizes the temporal reversing and still maintains its features even after undergoing a complete wavelength conversion process. Different comb-like spectra are created in the presence of Raman effect by changing the duration of the Airy pulse. The rebounds of Airy pulse in a twin-soliton trapping process is investigated. Meanwhile, a "maximally compressed" Akhmediev Breather is employed to collide with a soliton to compare with the Airy-soliton horizon case. The result can be found in the potential applications of pulse reshaping and temporal-spectral imaging for optical communication and signal processing.

15.
Appl Microbiol Biotechnol ; 102(15): 6503-6513, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29754163

RESUMO

Glioblastoma, characterized by extensive microvascular proliferation and invasive tumor growth, is one of the most common and lethal malignancies in adults. Benefits of the conventional anti-angiogenic therapy were only observed in a subset of patients and limited by diverse relapse mechanism. Fortunately, recent advances in cancer immunotherapy have offered new hope for patients with glioblastoma. Herein, we reported a novel dual-targeting therapy for glioblastoma through simultaneous blockade of VEGF and CD47 signaling. Our results showed that VEGFR1D2-SIRPαD1, a VEGF and CD47 bispecific fusion protein, exerted potent anti-tumor effects via suppressing VEGF-induced angiogenesis and activating macrophage-mediated phagocytosis. Meanwhile, autophagy was activated by VEGFR1D2-SIRPαD1 through inactivating Akt/mTOR and Erk pathways in glioblastoma cells. Importantly, autophagy inhibitor or knockdown of autophagy-related protein 5 potentiated VEGFR1D2-SIRPαD1-induced macrophage phagocytosis and cytotoxicity against glioblastoma cells. Moreover, suppression of autophagy led to increased macrophage infiltration, angiogenesis inhibition, and tumor cell apoptosis triggered by VEGF and CD47 dual-targeting therapy, thus eliciting enhanced anti-tumor effects in glioblastoma. Our data revealed that VEGFR1D2-SIRPαD1 alone or in combination with autophagy inhibitor could effectively elicit potent anti-tumor effects, highlighting potential therapeutic strategies for glioblastoma through disrupting angiogenetic axis and CD47-SIRPα anti-phagocytic axis alone or in combination with autophagy inhibition.


Assuntos
Autofagia/efeitos dos fármacos , Antígeno CD47/antagonistas & inibidores , Glioblastoma/tratamento farmacológico , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Xenoenxertos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fagocitose/efeitos dos fármacos
16.
Mikrochim Acta ; 185(2): 112, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29594661

RESUMO

Persistent organic pollutants (POPs) are key pollutants due to their persistence, refractory biodegradation, high toxicity and bioaccumulation in the food chain. This review (with 93 refs.) covers the progress made in the past decades in the application of carbonaceous materials for electrochemical detection of POPs as listed in the Stockholm Convention. Following an introduction into the field, typical carbonaceous materials for use in electrodes are discussed, with subsection on carbon nanotubes, graphene, reduced graphene oxide, graphitic carbon nitride and carbon dots. This is followed by a section on application of carbonaceous materials in electrochemical detection, with subsections on the use of carbon nanotubes, of (doped-) graphene, of reduced graphene oxide, of graphitic carbon nitride, and of carbon dots. The review concludes with conclusions and future perspectives. The detection mechanisms of POPs are also discussed. Graphical abstract Advanced carbonaceous materials for the electrochemical determination of persistent organic pollutants.

17.
Small ; 13(34)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28714242

RESUMO

Rechargeable batteries based on an abundant metal such as aluminum with a three-electron transfer per atom are promising for large-scale electrochemical energy storage. Aluminum can be handled in air, thus offering superior safety, easy fabrication, and low cost. However, the development of Al-ion batteries has been challenging due to the difficulties in identifying suitable cathode materials. This study presents the use of a highly open framework Mo2.5 + y VO9 + z as a cathode for Al-ion batteries. The open-tunnel oxide allows a facile diffusion of the guest species and provides sufficient redox centers to help redistribute the charge within the local host lattice during the multivalent-ion insertion, thus leading to good rate capability with a specific capacity among the highest reported in the literature for Al-based batteries. This study also presents the use of Mo2.5 + y VO9 + z as a model host to develop a novel ultrafast technique for chemical insertion of Al ions into host structures. The microwave-assisted method employing diethylene glycol and aluminum diacetate (Al(OH)(C2 H3 O2 )2 ) can be performed in air in as little as 30 min, which is far superior to the traditional chemical insertion techniques involving moisture-sensitive organometallic reagents. The Al-inserted Al x Mo2.5 + y VO9 + z obtained by the microwave-assisted chemical insertion can be used in Al-based rechargeable batteries.

18.
Angew Chem Int Ed Engl ; 56(45): 14246-14251, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-28940964

RESUMO

Achieving high membrane performance in terms of gas permeance and carbon dioxide selectivity is an important target in carbon capture. Aiming to manipulate the channel affinity towards CO2 to implement efficient separations, gas separation membranes containing CO2 -philic and non-CO2 -philic nanodomains in the interlayer channels of graphene oxide (GO) were formed by intercalating poly(ethylene glycol) diamines (PEGDA). PEGDA reacts with epoxy groups on the GO surface, constructing CO2 -philic nanodomains and rendering a high sorption capacity, whereas unreacted GO surfaces give non-CO2 -philic nanodomains, rendering low-friction diffusion. Owing to the orderly stacking of nanochannels through cross-linking and the heterogeneous nanodomains with moderate CO2 affinity, a GO-PEGDA500 membrane exhibits a high CO2 permeance of 175.5 GPU and a CO2 /CH4 selectivity of 69.5, which is the highest performance reported for dry-state GO-stacking membranes.

19.
J Am Chem Soc ; 138(30): 9385-8, 2016 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-27440104

RESUMO

A cross-linked polymer containing pendant molecules attached to the polymer framework is shown to form flexible and low-cost membranes, to be a solid Li(+) electrolyte up to 270 °C, much higher than those based on poly(ethylene oxide), to be wetted by a metallic lithium anode, and to be not decomposed by the metallic anode if the anions of the salt are blocked by a ceramic electrolyte in a polymer/ceramic membrane/polymer sandwich electrolyte (PCPSE). In this sandwich architecture, the double-layer electric field at the Li/polymer interface is reduced due to the blocked salt anion transfer. The polymer layer adheres/wets the lithium metal surface and makes the Li-ion flux at the interface more homogeneous. This structure integrates the advantages of the ceramic and polymer. With the PCPSE, all-solid-state Li/LiFePO4 cells showed a notably high Coulombic efficiency of 99.8-100% over 640 cycles.

20.
Tumour Biol ; 37(5): 6627-35, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26643895

RESUMO

Recombinant human arginase (rhArg) is an arginine-degrading enzyme that has been evaluated as effective therapeutics for varieties of malignant tumors and is in clinical trials for hepatocellular carcinoma (HCC) treatment nowadays. Our previous studies have reported that rhArg could induce autophagy and apoptosis in lymphoma cells and inhibiting autophagy could enhance the efficacy of rhArg on lymphoma. However, whether rhArg could induce autophagy and what roles autophagy plays in leukemia cells are unclear. In this study, we demonstrated that rhArg treatment could lead to the formation of autophagosomes and the upregulation of microtubule-associated protein light chain 3 II (LC3-II) in human promyelocytic leukemia HL-60 cells and human acute T cell leukemia Jurkat cells. Furthermore, inhibiting autophagy using 3-methyladenine (3-MA) or chloroquine (CQ) could significantly enhance rhArg-induced cell growth inhibition and apoptosis. Taken together, these findings indicated that rhArg induced autophagy in leukemia cells and inhibiting autophagy enhanced anti-leukemia effect of rhArg, which might encourage the treatment of leukemia by targeting arginine depletion and autophagy in clinics.


Assuntos
Antineoplásicos/farmacologia , Arginase/farmacologia , Autofagia/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HL-60 , Humanos , Células Jurkat , Leucemia/genética , Leucemia/metabolismo
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