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1.
Exp Cell Res ; 434(1): 113867, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043723

RESUMO

Long-term stem cell survival in the cirrhotic liver niche to maintain therapeutic efficacy has not been achieved. In a well-defined diethylnitrosamine (DEN)-induced liver fibrosis/cirrhosis animal model, we previously showed that liver-resident stem/progenitor cells (MLpvNG2+ cells) or immune cells have improved survival in the fibrotic liver environment but died via apoptosis in the cirrhotic liver environment, and increased levels of hepatocyte growth factor (HGF) mediated this cell death. We tested the hypothesis that inhibiting HGF signaling during the cirrhotic phase could keep the cells alive. We used adeno-associated virus (AAV) vectors designed to silence the c-Met (HGF-only receptor) gene or a neutralizing antibody (anti-cMet-Ab) to block the c-Met protein in the DEN-induced liver cirrhosis mouse model transplanted with MLpvNG2+ cells between weeks 6 and 7 after DEN administration, which is the junction of liver fibrosis and cirrhosis at the site where most intrahepatic stem cells move toward apoptosis. After 4 weeks of treatment, the transplanted MLpvNG2+ cells survived better in c-Met-deficient mice than in wild-type mice, and cell activity was similar to that of the mice that received MLpvNG2+ cells at 5 weeks after DEN administration (liver fibrosis phase when most of these cells proliferated). Mechanistically, a lack of c-Met signaling remodeled the cirrhotic environment, which favored transplanted MLpvNG2+ cell expansion to differentiation into mature hepatocytes and initiate endogenous regeneration by promoting mature host hepatocyte generation and mediating functional improvements. Therapeutically, c-Met-mediated regeneration can be mimicked by anti-cMet-Ab to interfere functions, which is a potential drug for cell-based treatment of liver fibrosis/cirrhosis.


Assuntos
Fator de Crescimento de Hepatócito , Fígado , Animais , Camundongos , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/terapia , Cirrose Hepática/patologia , Hepatócitos/metabolismo , Células-Tronco/metabolismo , Regeneração Hepática
2.
J Am Chem Soc ; 145(35): 19274-19282, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37585588

RESUMO

To promote the commercialization of direct formic acid fuel cell (DFAFC), it is vital to explore new types of direct formic acid oxidation (FAOR) catalysts with high activity and direct pathway. Here, we report the synthesis of intermetallic platinum-lead/platinum nanoplates inlaid with sub-monolayer antimony oxide surface (PtPb/Pt@sub-SbOx NPs) for efficient catalytic applications in FAOR. Impressively, they can achieve the remarkable FAOR specific and mass activities of 28.7 mA cm-2 and 7.2 A mgPt-1, which are 151 and 60 times higher than those of the state-of-the-art commercial Pt/C, respectively. Furthermore, the X-ray photoelectron spectroscopy and X-ray absorption spectroscopy results collectively reveal the optimization of the local coordination environment by the surface sub-monolayer SbOx, along with the electron transfer from Pb and Sb to Pt, driving the predominant dehydrogenation process. The sub-monolayer SbOx on the surface can effectively attenuate the CO generation, largely improving the FAOR performance of PtPb/Pt@sub-SbOx NPs. This work develops a class of high-performance Pt-based anodic catalyst for DFAFC via constructing the unique intermetallic core/sub-monolayer shell structure.

3.
J Am Chem Soc ; 145(28): 15109-15117, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37289521

RESUMO

Designing platinum (Pt)-based formic acid oxidation reaction (FAOR) catalysts with high performance and high selectivity of direct dehydrogenation pathway for direct formic acid fuel cell (DFAFC) is desirable yet challenging. Herein, we report a new class of surface-uneven PtPbBi/PtBi core/shell nanoplates (PtPbBi/PtBi NPs) as the highly active and selective FAOR catalysts, even in the complicated membrane electrode assembly (MEA) medium. They can achieve unprecedented specific and mass activities of 25.1 mA cm-2 and 7.4 A mgPt-1 for FAOR, 156 and 62 times higher than those of commercial Pt/C, respectively, which is the highest for a FAOR catalyst by far. Simultaneously, they show highly weak adsorption of CO and high dehydrogenation pathway selectivity in the FAOR test. More importantly, the PtPbBi/PtBi NPs can reach the power density of 161.5 mW cm-2, along with a stable discharge performance (45.8% decay of power density at 0.4 V for 10 h), demonstrating great potential in a single DFAFC device. The in situ Fourier transform infrared spectroscopy (FTIR) and X-ray absorption spectroscopy (XAS) results collectively reveal a local electron interaction between PtPbBi and PtBi. In addition, the high-tolerance PtBi shell can effectively inhibit the production/adsorption of CO, resulting in the complete presence of the dehydrogenation pathway for FAOR. This work demonstrates an efficient Pt-based FAOR catalyst with 100% direct reaction selectivity, which is of great significance for driving the commercialization of DFAFC.

4.
BMC Cancer ; 23(1): 649, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438709

RESUMO

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is the most common renal malignancy, although newly developing targeted therapy and immunotherapy have been showing promising effects in clinical treatment, the effective biomarkers for immune response prediction are still lacking. The study is to construct a gene signature according to ccRCC immune cells infiltration landscape, thus aiding clinical prediction of patients response to immunotherapy. METHODS: Firstly, ccRCC transcriptome expression profiles from Gene Expression Omnibus (GEO) database as well as immune related genes information from IMMPORT database were combine applied to identify the differently expressed meanwhile immune related candidate genes in ccRCC comparing to normal control samples. Then, based on protein-protein interaction network (PPI) and following module analysis of the candidate genes, a hub gene cluster was further identified for survival analysis. Further, LASSO analysis was applied to construct a signature which was in succession assessed with Kaplan-Meier survival, Cox regression and ROC curve analysis. Moreover, ccRCC patients were divided as high and low-risk groups based on the gene signature followed by the difference estimation of immune treatment response and exploration of related immune cells infiltration by TIDE and Cibersort analysis respectively among the two groups of patients. RESULTS: Based on GEO and IMMPORT databases, a total of 269 differently expressed meanwhile immune related genes in ccRCC were identified, further PPI network and module analysis of the 269 genes highlighted a 46 genes cluster. Next step, Kaplan-Meier and Cox regression analysis of the 46 genes identified 4 genes that were supported to be independent prognosis indicators, and a gene signature was constructed based on the 4 genes. Furthermore, after assessing its prognosis indicating ability by both Kaplan-Meier and Cox regression analysis, immune relation of the signature was evaluated including its association with environment immune score, Immune checkpoint inhibitors expression as well as immune cells infiltration. Together, immune predicting ability of the signature was preliminary explored. CONCLUSIONS: Based on ccRCC genes expression profiles and multiple bioinformatic analysis, a 4 genes containing signature was constructed and the immune regulation of the signature was preliminary explored. Although more detailed experiments and clinical trials are needed before potential clinical use of the signature, the results shall provide meaningful insight into further ccRCC immune researches.


Assuntos
Carcinoma de Células Renais , Carcinoma , Neoplasias Renais , Humanos , Carcinoma de Células Renais/genética , Prognóstico , Neoplasias Renais/genética , Imunoterapia
5.
Phys Chem Chem Phys ; 25(15): 10635-10646, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37000580

RESUMO

The electrification of heavy-duty transport and aviation urgently requires new strategies to develop high-rate lithium-ion batteries (LIBs) whose performance fundamentally relies on electrode materials. However, commercially available graphite anodes still suffer from slow kinetics of lithium-ion diffusion and severe safety concerns of lithium plating when achieving the high-rate use goal. Herein, taking Ti3C2Tx as an example, it is demonstrated that N and S co-doping in Ti3C2Tx results in a high-rate MXene anode for LIBs. Nitrogen doping not only flattens the MXene layers and expands the interlayer spacing but also increases the Ti valence state change ability. As evidenced by density functional theory calculations, the diffusion barriers of S-containing Ti3C2Tx MXenes are lower than those of the S-free counterpart, suggesting that S plays an essential role in achieving high-rate performance. Therefore, the N and S co-doped Ti3C2Tx anode in LIBs exhibited excellent performance with a reversible capacity of 113.8 mA h g-1 at a rate of 3C and ∼89% capacity retention after 1000 charge/discharge cycles. The high capacity is attributed to the change in the oxidation states of both Ti and O elements, and the tiny volume change within ∼0.6% upon the stable charging/discharging process accounts for the good capacity retention. When paired up with a LiFe0.5Mn0.5PO4 cathode, the full cell delivers a reversible capacity of 134 mA h g-1 after 1000 cycles at a high rate of 1C. The demonstration of N and S co-doped Ti3C2Tx MXenes in this work may offer a feasible approach for high-rate intercalation anode materials.

6.
Angew Chem Int Ed Engl ; 62(3): e202213783, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36400747

RESUMO

High-entropy alloys (HEAs) have been attracting extensive research interests in designing advanced nanomaterials, while their precise control is still in the infancy stage. Herein, we have reported a well-defined PtBiPbNiCo hexagonal nanoplates (HEA HPs) as high-performance electrocatalysts. Structure analysis decodes that the HEA HP is constructed with PtBiPb medium-entropy core and PtBiNiCo high-entropy shell. Significantly, the HEA HPs can reach the specific and mass activities of 27.2 mA cm-2 and 7.1 A mgPt -1 for formic acid oxidation reaction (FAOR), being the record catalyst ever achieved in Pt-based catalysts, and can realize the membrane electrode assembly (MEA) power density (321.2 mW cm-2 ) in fuel cell. Further experimental and theoretical analyses collectively evidence that the hexagonal intermetallic core/atomic layer shell structure and multi-element synergy greatly promote the direct dehydrogenation pathway of formic acid molecule and suppress the formation of CO*.

7.
Small ; 18(43): e2106143, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35199957

RESUMO

Supported alloy catalysts play a pivotal role in many heterogeneous catalytic processes of socioeconomic and environmental importance. But the controlled synthesis of supported alloy nanoparticles with consistent composition and tight size distribution remains a challenging issue. Herein, a simple yet effective method for preparation of highly dispersed, homogeneously alloyed bimetallic nanoparticles on oxide supports is reported. This method is based on solid solution of metal cations in parent oxide and strong electrostatic adsorption of a secondary metal species onto the oxide surface. In the reductive annealing process, hydrogen spillover occurs from the surface metal with a higher reduction potential to the solute metal in solid solution, leading to metal exsolution and homogenous alloying of the metals on the oxide surface. The ceria-supported Ni-Pt alloy is chosen as a model catalyst and hydrazine monohydrate decomposition is chosen as a probe reaction to demonstrate this method, and particularly its advantages over the conventional impregnation and galvanic replacement methods. A systematic application of this method using different oxides and base-noble metal pairs further elucidates its applicability and generality.


Assuntos
Nanopartículas , Óxidos , Ligas , Oxirredução , Metais , Hidrogênio
8.
Anal Biochem ; 656: 114857, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36044933

RESUMO

An ultrasensitive mini-sensor has been developed for nonenzymatic and noninvasive determination of trace glucose in saliva. The miniature detector exhibits ultra-high sensitivity and resolution at very low glucose concentration owing to the excellent electrocatalytic activity and electron transfer rate of the prepared 3D ordered CuO nanoflake array in-situ grown on a copper foil. The structure and morphology of the cupric oxide nanoarray were characterized by X-ray powder diffraction and scanning electron microscopy. The electrocatalysis of the CuO nanoarray modified electrode to glucose was demonstrated by cyclic voltammetry and chronoamperometry. The modified electrode presents a high sensitivity of 4954 µA mM-1 cm-2 to glucose at + 0.55 V with a wide linear range of 1.0 µmol/L to 6000 µmol/L and a low detection limit of 0.1 µmol/L and long-term stability. Furthermore, the mini-sensor can clearly distinguish diabetics from healthy people because of its excellent sensing performance. The developed miniaturized sensor holds the prospect for noninvasive determination of trace glucose in saliva for diabetic patients.


Assuntos
Técnicas Biossensoriais , Cobre , Técnicas Biossensoriais/métodos , Cobre/química , Eletrodos , Transporte de Elétrons , Glucose/química , Humanos
9.
BMC Ophthalmol ; 22(1): 404, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36217120

RESUMO

BACKGROUND: To compare the accuracy of non-contact tonometry, Pentacam, and corneal visualization Scheimpflug technology (Corvis ST) for the measurement of intraocular pressure (IOP) after small incision lenticule extraction (SMILE) or femtosecond laser-assisted in situ keratomileusis (FS-LASIK) surgery. METHODS: A total of 49 patients (98 eyes) undergoing FS-LASIK or SMILE surgery at West China Hospital, Sichuan University from January to March 2021 were enrolled in this prospective, comparative, self-controlled study. IOP values were measured with non-contact tonometer, Pentacam, and Corvis ST before surgery and 1 month after surgery. Pentacam-derived postoperative IOP values were corrected using five correction formulas (Ehlers, Shah, Dresden, Orssengo-Pye, and Kohlhaas), while Corvis ST-derived values were corrected using a single formula. RESULTS: In the SMILE group, no significant differences were observed between the IOP values corrected with the Shah formula before and after surgery (t = 0.17, P = 0.869), whereas postoperative IOP values corrected with the other formulas were significantly different from the corresponding preoperative measurements (P < 0.05). In the FS-LASIK group, postoperative IOP values corrected with the Ehlers, Shah, or Corvis ST formulas were significantly different from the corresponding preoperative IOP measurements (P < 0.05), but no significant differences were observed between pre- and postoperative IOP values corrected with the Dresden (t = - 0.08, P = 0.941), Orssengo-Pye (t = - 0.52, P = 0.604), or Kohlhaas (t = 1.22, P = 0.231) formulas. CONCLUSIONS: Pentacam's Shah correction formula seemed to be the most appropriate method for accurately measuring postoperative IOP in patients undergoing SMILE surgery, while the Dresden, Orssengo-Pye, and Kohlhaas correction formulas of Pentacam were identified as the most reliable methods for estimating IOP in patients after FS-LASIK surgery.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ , Miopia , Córnea/cirurgia , Substância Própria/cirurgia , Humanos , Pressão Intraocular , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Estudos Prospectivos
10.
J Mol Recognit ; 34(11): e2919, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34137098

RESUMO

Pathogens are one of the important factors affecting national economic construction. An ideal detection system for pathogen control with excellent sensitivity, high specificity, and time-saving is needed. Here, we reported a method for bacterial detection using gold nanoparticles-mediated fluorescent "chemical nose" sensors (GFCEs). The technique consists of gold nanoparticles-coated magnetic particle using benzaldehyde, octyl aldehyde, and pyrimidine-4-formaldehyde modified, respectively. And these positively charged nanocompound interacting with three different fluorescent proteins (FPs) to form three kinds of GFCEs, respectively, named GFCE1, GFCE2, and GFCE3. Upon binding with pathogenic cells, functionalized gold nanoparticles could identify patches on hydrophobic/functional surfaces of microorganisms, and self-assemble with living bacteria by complementary electrostatic interactions. The binding ability between GFCEs and bacteria determines the change of fluorescence response of three FPs from GFCEs. These feature fluorescent level are pathogen-specific, highly repeatable, and can be analyzed by Linear Discriminant Analysis (LDA). The combination of GFCE1 and GFCE2 has the best performance when detecting pathogens with concentrations of 106 cfu mL-1 . The first discriminant within 15 minutes is 93.8%, which could be used for subsequent identification of unknown samples. The commonly applicable system provides a simple way for the rapid bacterial detection without preprocessing procedures.


Assuntos
Bactérias/patogenicidade , Infecções Bacterianas/diagnóstico , Fluorescência , Ouro/química , Proteínas Luminescentes/metabolismo , Nanopartículas Metálicas/química , Polímeros/química , Infecções Bacterianas/metabolismo
11.
Phys Chem Chem Phys ; 23(40): 23173-23183, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34618881

RESUMO

MXenes represent an emerging family of two-dimensional materials of transition metal carbides/carbonitrides terminated with functional groups like -O, -OH, and -F on the chemically active surface of MX slabs. As a member of the family, Nb2CTx exhibits superior lithium storage capacity over most of the other MXenes as anode materials in lithium-ion batteries (LIBs). However, an in-depth understanding of the charge storage mechanism is still lacking so far. Here, through combining complementary experiments and density functional theory calculations, we provide insights into the (de)lithiation process. Specifically, Nb2CTx with dominant -O functional groups stores charge as a result of changes in the oxidation states of both transition metals Nb and O, which is supported by Bader charge analysis showing a significant change in the oxidation states of Nb and O upon lithiation. As monitored by ex situ X-ray diffraction, the interlayer spacing of Nb2CTx changes slightly upon lithium ion (de)intercalation, corresponding to a volume change of only 2.3% with a near zero-strain feature. By coupling with a LiFePO4/C cathode, the full cell presents superior rate capability and cycling stability as well. The insights into the charge storage mechanism of Nb2CTx in this work provide useful guidance for the rational design of MXene-based anode materials for high-performance LIBs.

12.
Angew Chem Int Ed Engl ; 60(32): 17570-17578, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34041833

RESUMO

The clinical application of chemodynamic therapy is impeded by the insufficient intracellular H2 O2 level in tumor tissues. Herein, we developed a supramolecular nanoparticle via a simple one-step supramolecular polymerization-induced self-assembly process using platinum (IV) complex-modified ß-cyclodextrin-ferrocene conjugates as supramolecular monomers. The supramolecular nanoparticles could dissociate rapidly upon exposure to endogenous H2 O2 in the tumor and release hydroxyl radicals as well as platinum (IV) prodrugs in situ, which is reduced into cisplatin to significantly promote the generation of H2 O2 in the tumor tissue. Thus, the supramolecular nanomedicine overcomes the limitation of conventional chemodynamic therapy via the self-augmented cascade radical generation and drug release. In addition, dissociated supramolecular nanoparticles could be readily excreted from the body via renal clearance to effectively avoid systemic toxicity and ensure long term biocompatibility of the nanomedicine. This work may provide new insights on the design and development of novel supramolecular nanoassemblies for cascade chemo/chemodynamic therapy.


Assuntos
Antineoplásicos/uso terapêutico , Portadores de Fármacos/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Polímeros/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , Complexos de Coordenação/uso terapêutico , Complexos de Coordenação/toxicidade , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Feminino , Compostos Ferrosos/síntese química , Compostos Ferrosos/metabolismo , Compostos Ferrosos/uso terapêutico , Compostos Ferrosos/toxicidade , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Metalocenos/síntese química , Metalocenos/metabolismo , Metalocenos/uso terapêutico , Metalocenos/toxicidade , Camundongos Endogâmicos BALB C , Nanomedicina/métodos , Nanopartículas/química , Nanopartículas/metabolismo , Nanopartículas/toxicidade , Platina/química , Polimerização , Polímeros/síntese química , Polímeros/metabolismo , Polímeros/toxicidade , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Pró-Fármacos/uso terapêutico , Pró-Fármacos/toxicidade , beta-Ciclodextrinas/síntese química , beta-Ciclodextrinas/metabolismo , beta-Ciclodextrinas/uso terapêutico , beta-Ciclodextrinas/toxicidade
13.
Angew Chem Int Ed Engl ; 60(45): 24241-24247, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34553468

RESUMO

As a CRISPR-Cas system (clustered regularly interspaced short palindromic repeats and CRISPR associated proteins), Cas14a1 can cis/trans cleave single-stranded DNA (ssDNA). Here, we describe an unreported capacity of Cas14a1: RNA can trigger the trans ssDNA cleavage. This Cas14a1-based RNA-activated detection platform (Amplification, Transcription, Cas14a1-based RNA-activated trans ssDNA cleavage, ATCas-RNA) has an outstanding specificity for the detection of target RNAs with point mutation resolution, which is better than that of the Cas14a1-based ssDNA-activation. Using ATCas-RNA via a fluorophore quencher-labeled ssDNA reporter (FQ), we were able to detect 1 aM pathogenic nucleic acid within 1 h, and achieve 100 % accuracy with 25 milk samples. This platform can serve as a new tool for high-efficiency nucleic acid diagnostics. Importantly, this work can expand our understanding of Cas14a1 and inspire further mechanisms and applications of Class-2 Cas systems.


Assuntos
Proteínas Associadas a CRISPR/metabolismo , DNA de Cadeia Simples/metabolismo , RNA/metabolismo , Sistemas CRISPR-Cas , Clivagem do DNA , DNA de Cadeia Simples/química , RNA/análise
14.
Ann Hepatol ; 19(1): 99-106, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31558421

RESUMO

INTRODUCTION AND OBJECTIVES: Liver regeneration plays a valuable significance for hepatectomies, and is mainly attributed to hepatocyte proliferation. MicroRNA-125a-3p was reported to be highly associated with liver regeneration process. We studied the underlying mechanism of the functional role of miR-125a-3p in liver regeneration. MATERIALS AND METHODS: The miR-125a-3p mimics and inhibitor vector were constructed and transfected into primary human liver HL-7702 cells, the transfected cell viability was detected using cell counting kit-8 (CCK-8). Cell cycle distribution was analyzed by flow cytometry. With Targetscan and OUGene prediction, the potential targets of miR-125 were verified by real-time quantitative PCR (qPCR) and luciferase reporter assays in turn. The overexpression vector of proline-rich acidic protein 1 (PRAP1) was constructed and co-transfected with miR-125a-3p mimics into HL-7702 cells, detecting the changes of proliferative capacity and cell cycle distribution. Western blot and qPCR performed to analyze gene expressions. RESULTS: Overexpressed miR-125a-3p notably increased the hepatocyte viability at 48h, and decreased the number of G1 phase cells (p<0.05). However, miR-125a-3p inhibition suppressed the development of hepatocytes. PRAP1 was the target of miR-125a-3p. After co-transfection with PRAP1 vector, hepatocyte viability was decrease and the G1 phase cell number was increased (p<0.05). More importantly, overexpressed PRAP1 notably decreased the mRNA and protein levels of cyclin D1, cyclin-dependent kinase 2 (CDK2) and cell division cycle 25A (CDC25A). CONCLUSION: The elevated miR-125a-3p positively correlated with hepatocyte viability and cell cycle progression due to the modulation of PRAP1, and miR-125a-3p may contribute to improving liver regeneration.


Assuntos
Proliferação de Células/genética , Hepatócitos/metabolismo , Regeneração Hepática/genética , Fígado/fisiologia , MicroRNAs/genética , Proteínas da Gravidez/genética , Western Blotting , Ciclo Celular/genética , Linhagem Celular , Sobrevivência Celular/genética , Ciclina D1/genética , Ciclina D1/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Fase G1 , Humanos , Reação em Cadeia da Polimerase , Proteínas da Gravidez/metabolismo , RNA Mensageiro/metabolismo , Fosfatases cdc25/genética , Fosfatases cdc25/metabolismo
15.
World J Surg Oncol ; 17(1): 142, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409370

RESUMO

BACKGROUND: The Pringle maneuver (PM) interrupts the blood flow through the hepatic artery and portal vein to help control bleeding. This study analyzes the effects of the intermittent Pringle maneuver (IPM) on the surgical process and postoperative liver injury. METHODS: This study retrospectively evaluated 182 hepatocellular carcinoma patients who underwent hepatectomy. In the IPM group, hepatic blood flow was intermittently interrupted via clamping, with cycles of 10 minutes of inflow occlusion followed by 5 minutes of reperfusion that were repeated until the end of the surgery. In the non-IPM group, liver resection was performed without hepatic vascular blockage. RESULTS: For postoperative complications, the incidence rates of ascites and pleural effusion in the IPM group were significantly lower than those in the non-IPM group. The postoperative hospitalization time in the IPM group was significantly lower than that in the non-IPM group (p=0.0008). On the first day after the operation, the platelet count was significantly lower (p=0.0381) but the prothrombin time (PT) (p=0.0195) and activated partial thromboplastin time (APTT) (p=0.0071) were significantly higher in the non-IPM group than those in the IPM group. At discharge, only albumin was significantly higher in the non-IPM group than that in the IPM group (p=0.0303). Regression analysis showed that a prolonged interruption time was related to increased ALT and AST levels on the first day after surgery, but not on the seventh day or at discharge. CONCLUSION: The IPM does not cause additional liver damage during hepatectomy, and use of the IPM results in shorter hospital stays compared to surgery without using the IPM. The results of this study require further confirmation because of the retrospective design.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Neoplasias Hepáticas/cirurgia , Fígado/irrigação sanguínea , Complicações Pós-Operatórias/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Feminino , Seguimentos , Humanos , Fígado/lesões , Fígado/cirurgia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
16.
J Environ Manage ; 250: 109492, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31479936

RESUMO

A self-made micro-electrolysis-circulatory system with the mixture regime of an upflow bed and reactor was tested for the pretreatment of industrial estate wastewater with a low ratio of biological to chemical oxygen demand (BOD5/COD) at room temperature, 1:1 vol ratio of sponge iron (SFe)/granular activated carbon (GAC), and an intermittent process in aeration and discharge. The system efficiency was evaluated in view of the effects of various processes (hydraulic retention time (HRT), fillers/wastewater ratio (S/L) and aeration). COD reduction of about 51% was obtained for industrial estate wastewater at an S/L ratio of 25%, refluence rate of 16 L/h, HRT of 24 h, and aeration of 60 L/h as the optimal conditions. The considerable change in the calculated BOD5/COD ratio, from 0.07 to 0.49, showed favorable application of the micro-electrolysis-circulatory system for the reductive and oxidative degradation of organic pollutants to enhance wastewater biodegradability. The reusability of the SFe was also investigated after three successive runs. On the basis of the results of Fe leaching, HRT, S/L ratio, scanning electron microscopy observation, and X-ray photoelectron spectroscopic analysis, the corrosion products facilitated by the inherent porosity of SFe played a significant role due to different oxygen conditions in the surface and internal layers. One result from the removal of organic pollutants dominated by the galvanic cell reactions between SFe and GAC was observed, and the integration coagulation in the bulk solution was mainly attributed to the leaching of Fe. The innovative approach described in this study provides a promising and economical technology for pretreatment of industrial wastewater prior to a biological process.


Assuntos
Sistema Cardiovascular , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Eletrólise , Resíduos Industriais , Eliminação de Resíduos Líquidos , Águas Residuárias
18.
Proc Natl Acad Sci U S A ; 111(21): 7522-6, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24821802

RESUMO

Graphene is an ultrathin, impervious membrane. The controlled introduction of nanoscale pores in graphene would lead to applications that involve water purification, chemical separation, and DNA sequencing. However, graphene nanopores are unstable against filling by carbon adatoms. Here, using aberration-corrected scanning transmission electron microscopy and density-functional calculations, we report that Si atoms stabilize graphene nanopores by bridging the dangling bonds around the perimeter of the hole. Si-passivated pores remain intact even under intense electron beam irradiation, and they were observed several months after the sample fabrication, demonstrating that these structures are intrinsically robust and stable against carbon filling. Theoretical calculations reveal the underlying mechanism for this stabilization effect: Si atoms bond strongly to the graphene edge, and their preference for tetrahedral coordination forces C adatoms to form dendrites sticking out of the graphene plane, instead of filling the nanopore. Our results provide a novel way to develop stable nanopores, which is a major step toward reliable graphene-based molecular translocation devices.


Assuntos
Grafite/química , Modelos Químicos , Nanoporos/ultraestrutura , Silício/química , Carbono/química , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/tendências
19.
Angew Chem Int Ed Engl ; 53(34): 8908-12, 2014 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-24981312

RESUMO

Chemical decoration of defects is an effective way to functionalize graphene and to study mechanisms of their interaction with environment. We monitored dynamic atomic processes during the formation of a rotary Si trimer in monolayer graphene using an aberration-corrected scanning-transmission electron microscope. An incoming Si atom competed with and replaced a metastable C dimer next to a pair of Si substitutional atoms at a topological defect in graphene, producing a Si trimer. Other atomic events including removal of single C atoms, incorporation and relocation of a C dimer, reversible C-C bond rotation, and vibration of Si atoms occurred before the final formation of the Si trimer. Theoretical calculations indicate that it requires 2.0 eV to rotate the Si trimer. Our real-time results provide insight with atomic precision for reaction dynamics during chemical doping at defects in graphene, which have implications for defect nanoengineering of graphene.

20.
Toxicon ; 245: 107788, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823652

RESUMO

Ginkgo biloba L. is a valuable plant, which can be used for medicine, food and ornamental purposes. Despite the above benefits, the components of ginkgolic acids (GA) in ginkgo are considered to cause allergies, embryotoxicity, liver damage and some other adverse reactions. However, the mechanism of GA induced liver injury is still unclear. In this study, we developed an acute liver injury model induced by GA in mice, and investigated the mechanism of GA induced liver injury from the perspectives of oxidative stress, steatosis, apoptosis, and immune response. Intraperitoneal injection of GA (400 mg/kg) can cause liver damage. The levels of serum transaminase, oxidation and triglycerides were increased, liver fibrosis, hepatocyte apoptosis, G2/M phase arrest of the hepatic cell cycle and monocyte infiltration in the liver were detected in GA-treated mice. Flow cytometry analysis of cells separated from the spleen showed that the proportion of Th1 and Th17 cells were increased, and the proportion of Th2 cells were decreased in GA-treated mice. The rise in Th1/Th2 ratio and Th17 cell ratio usually cause inflammatory problems. At the same time, cleaved Caspase-8 and Caspase-3 were detected in hepatocytes, indicating that GA may induce apoptosis through FADD pathway. Although GA is capable of causing the above problems, the inflammation and damage in liver tissue are not severe and there are certain individual differences. Our study reveals the potential hepatotoxicity of GA in ginkgo and its mechanism of action, providing a new perspective for the intervention and prevention of ginkgo toxicity.


Assuntos
Apoptose , Doença Hepática Induzida por Substâncias e Drogas , Salicilatos , Animais , Camundongos , Salicilatos/toxicidade , Apoptose/efeitos dos fármacos , Ginkgo biloba , Estresse Oxidativo/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino
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