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1.
Eur Radiol ; 31(7): 4764-4773, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33399908

RESUMO

OBJECTIVES: We aimed to compare the therapeutic outcomes of radiofrequency ablation (RFA) and microwave ablation (MWA) as first-line therapies in patients with small single perivascular hepatocellular carcinoma (HCC). METHODS: A total of 144 eligible patients with small (≤ 3 cm) single perivascular (proximity to hepatic and portal veins) HCC who underwent RFA (N = 70) or MWA (N = 74) as first-line treatment were included. The overall survival (OS), disease-free survival (DFS), and local tumor progression (LTP) rates between the two ablation modalities were compared. The inverse probability of treatment weighting (IPTW) method was used to reduce selection bias. Subgroup analysis was performed according to the type of hepatic vessels. RESULTS: After a median follow-up time of 38.2 months, there were no significant differences in OS (5-year OS: RFA 77.7% vs. MWA 74.6%; p = 0.600) and DFS (5-year DFS: RFA 24.7% vs. MWA 40.4%; p = 0.570). However, a significantly higher LTP rate was observed in the RFA group than the MWA group (5-year LTP: RFA 24.3% vs. MWA 8.4%; p = 0.030). IPTW-adjusted analyses revealed similar results. The treatment modality (RFA vs. MWA: HR 7.861, 95% CI 1.642-37.635, p = 0.010) was an independent prognostic factor for LTP. We observed a significant interaction effect of ablation modality and type of peritumoral vessel on LTP (p = 0.034). For patients with periportal HCC, the LTP rate was significantly higher in the RFA group than in the MWA group (p = 0.045). However, this difference was not observed in patients with perivenous HCC (p = 0.116). CONCLUSIONS: In patients with a small single periportal HCC, MWA exhibited better tumor control than RFA. KEY POINTS: • Microwave ablation exhibited better local tumor control than radiofrequency ablation for small single periportal hepatocellular carcinoma. • There was a significant interaction between the treatment effect of ablation modality and type of peritumoral vessel on local tumor progression. • The type of peritumoral vessel is vital in choosing ablation modalities for hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Neoplasias Hepáticas , Ablação por Radiofrequência , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/cirurgia , Micro-Ondas/uso terapêutico , Pontuação de Propensão , Estudos Retrospectivos , Resultado do Tratamento
2.
Nanoscale ; 7(14): 5955-62, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25771786

RESUMO

A combustion flame method is developed for the convenient and scalable fabrication of single- and dual-doped carbon quantum dots (CQDs) (N-CQDs, B-CQDs, P-CQDs, and S-CQDs and dual-doped B,N-CQDs, P,N-CQDs, and S,N-CQDs), and the doping contents can be easily adjusted by simply changing the concentrations of precursors in ethanol. These single/dual-doped CQDs, especially B,N-CQDs, show high catalytic activities for the oxygen reduction reaction.

3.
Science ; 347(6225): 970-4, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25722405

RESUMO

The use of solar energy to produce molecular hydrogen and oxygen (H2 and O2) from overall water splitting is a promising means of renewable energy storage. In the past 40 years, various inorganic and organic systems have been developed as photocatalysts for water splitting driven by visible light. These photocatalysts, however, still suffer from low quantum efficiency and/or poor stability. We report the design and fabrication of a metal-free carbon nanodot-carbon nitride (C3N4) nanocomposite and demonstrate its impressive performance for photocatalytic solar water splitting. We measured quantum efficiencies of 16% for wavelength λ = 420 ± 20 nanometers, 6.29% for λ = 580 ± 15 nanometers, and 4.42% for λ = 600 ± 10 nanometers, and determined an overall solar energy conversion efficiency of 2.0%. The catalyst comprises low-cost, Earth-abundant, environmentally friendly materials and shows excellent stability.

4.
J Mater Chem B ; 3(7): 1198-1203, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32264471

RESUMO

In this study, we provide the quantitative data on the membrane permeability of a HeLa cell in the presence of different sizes of SiO2 nanoparticles (NPs, 50, 100 and 200 nm). SiO2 NPs have low cytotoxicity, but 50 and 100 nm SiO2 NPs can increase the cell membrane permeability (a reversible effect) by 12.5% (0.02 mg mL-1, 4 min) and 9% (0.02 mg mL-1, 6 min), respectively. However, the 200 nm SiO2 NPs cannot affect the cell membrane permeability.

5.
Phys Chem Chem Phys ; 16(46): 25350-7, 2014 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-25338313

RESUMO

The porous cobalt, nitrogen-codoped carbon materials (Co/N/C) were synthesized by a facile one-step pyrolysis of vitamin B12 (VB12) and carbon quantum dots (CQDs). Varying the initial mass ratio of CQDs and VB12 leads to controllable concentrations of Co (0% to 3.68%) and N (0% to 5.88%) after pyrolysis. The obtained Co/N/C was evaluated by oxygen reduction reaction (ORR) in both alkaline and acid media. Particularly, the Co/N/C with 1.12% Co and 2.92% N prepared at 700 °C (Co1.12/N2.92/C-700) exhibited the best catalytic ability for ORR with a cathodic peak at -0.165 and 0.185 V (vs. SCE) in 0.1 M KOH and 0.1 M HClO4 solution, respectively, which are comparable to that of Pt/C (20%). The Co1.12/N2.92/C-700 also showed long-term stability and high methanol tolerance, which outperformed commercial Pt/C (20%).

6.
Dalton Trans ; 43(40): 15119-25, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25178089

RESUMO

Tailoring high performance, stable, and earth-abundant electrocatalysts for water oxidation is of fundamental importance for the development of promising energy conversion and storage technologies. In this work, we report a remarkably simple and efficient approach for the preparation of ZnCo-layered double hydroxides and reduced graphene oxide (RGO/ZnCo-LDH) nanocomposites via a facile one-pot coprecipitation method. The resulting RGO/ZnCo-LDH complex investigated for the first time as a catalyst for oxygen evolution reaction (OER) exhibits higher electrocatalytic activity (with onset overpotential ∼330 mV in 0.1 M KOH) and excellent stability than pristine ZnCo-layered double hydroxides and commercial Pt/C, making it a highly efficient nonprecious metal-based novel LDH composite electrocatalyst for OER.

7.
Neural Regen Res ; 9(8): 815-20, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25206894

RESUMO

The Nogo receptor is an essential factor for neuronal apoptosis, but the changes in Nogo receptor expression in the retina and the effects of the Nogo receptor on retinal ganglion cell apoptosis in diabetes mellitus remain unclear. We found that Nogo receptor expression was mainly visible in retinal ganglion cells of a rat model of diabetes mellitus induced by streptozotocin. At 12 weeks after onset of diabetes mellitus, Nogo receptor and Rho kinase expression significantly increased in the retina, and retinal ganglion cell apoptosis was apparent. When RNA interference was used to suppress Nogo receptor expression in rat retina, Rho kinase expression was obviously inhibited, and retinal ganglion cell apoptosis was evidently reduced in rats with diabetes mellitus. These results indicate that upregulation of Nogo receptor expression is an important mechanism of retinal ganglion cell apoptosis in rats with diabetes mellitus.

8.
ACS Appl Mater Interfaces ; 6(10): 7918-25, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24735390

RESUMO

The design of highly efficient, durable, and earth-abundant catalysts for the oxygen evolution reaction is crucial to a variety of important energy conversion and storage processes. Here, we use carbon quantum dots (CQDs, ∼5 nm) to form hybrids with the ultrathin nickel-iron layered double-hydroxide (NiFe-LDH) nanoplates. The resulting CQD/NiFe-LDH complex exhibits high electrocatalytic activity (with an overpotential of ∼235 mV in 1 M KOH at a current density of 10 mA cm(-2)) and stability for oxygen evolution, which almost exceed the values of all previously reported Ni-Fe compounds and were comparable to those of the most active perovskite-based catalyst.

9.
Dalton Trans ; 42(29): 10380-3, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23764645

RESUMO

We report a facile hydrolytic process for the preparation of CQDs/SiO2 porous nanocomposites, which show high catalytic activity and stability for the selective oxidation of cis-cyclooctene under visible light irradiation, with TBHP as a radical initiator and oxygen (in the air) as an oxidant at 80 °C.

10.
Dalton Trans ; 42(18): 6285-9, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23519004

RESUMO

Carbon quantum dots (CQDs) were demonstrated to have the ability to enhance the photocatalytic performance of monoclinic BiVO4 with different exposed facets under visible light.

11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 46(4): 210-3, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21612708

RESUMO

OBJECTIVE: To investigate the function of luxS in sulfurmetabolism of Streptococcus mutans (Sm). METHODS: The growth with absorbency (A) of the standards and mutant strains was measured and analyzed in the sulfur-limited defined medium at different periods. The laser scanning confocal microscopy (LSCM) was used to observe and compare the biofilm thickness of the two kinds of strains at different culture conditions. RESULTS: The significant increases in the thickness of mutant strain biofilm and its growth were observed after the addition of cysteine, but did not reach the standards strain levels (P < 0.05). The growth and the biofilm thickness of the mutant strains were (1.301 ± 0.009) and (45.009 ± 0.429) µm. When methionine and S-adenosylhomocysteine of certain concentrations were respectively added, the biofilm thickness and the growth of mutant strain were raised but did not reach the level of the standards strain at 24 h (P < 0.05), but at 48 h they did. When the methionine was added in the mutant strains for 24 h, the biofilm thickness and the growth of mutant strain were (0.448 ± 0.028) and (37.068 ± 2.392) µm, as for the adding of S-adenosylhomocysteine were (0.460 ± 0.005) and (27.343 ± 1.107) µm. When adding the supernatant fluid of standard strains, the biofilm thickness and the growth levels of mutant strain were much higher than those of the standards strain. The biofilm thickness and growth of both kinds of strains decreased after the addition of S-adenosylmethionine. CONCLUSIONS: luxS gene plays not only a role in quorum sensing but also a role in sulfurmetabolism.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Liases de Carbono-Enxofre/metabolismo , Percepção de Quorum , Streptococcus mutans/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Liases de Carbono-Enxofre/genética , Meios de Cultura , Técnicas de Cultura , Cisteína/metabolismo , Regulação Bacteriana da Expressão Gênica , Metionina/metabolismo , Microscopia Confocal , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Streptococcus mutans/genética , Streptococcus mutans/metabolismo , Enxofre/metabolismo
12.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 46(2): 102-6, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21426780

RESUMO

OBJECTIVE: To construct double gene deletions at the htrA and clpP loci on the chromosome of Streptococcus mutans (Sm) and to remove the antibiotic resistance markers with the Cre-loxP(*) site-specific recombination system. METHODS: The htrA gene was cloned into the pGEM-T-Easy TA cloning vector and then inactivated via the insertion of a kanamycin resistance cassette (lox71-Km-lox66), yielding pGEM-T-ΔhtrA/Km for deleting the htrA gene. Using the same method, the pGEM-T-ΔclpP/Sp was constructed for deleting the clpP gene. Following the transformation of pGEM-T-ΔhtrA/Km in Sm, the homologous recombination event was selected. One such mutant was transformed with a cre expression plasmid (pCrePA). The kanamycin resistance gene was then excised. The pCrePA was then easily eliminated at nonpermissive temperatures, resulting in a mutant strain (MSΔhtrA) carrying a deletion at the htrA loci without a selectable marker. This mutant was verified by PCR and DNA sequencing. Then, the clpP and spectinomycin resistance gene were deleted from MSΔhtrA, yielding markerless mutant strain lacking clpP and htrA. RESULTS: The deletion of htrA, clpP and antibiotic resistance markers were confirmed by PCR analysis and DNA sequencing. CONCLUSIONS: A mutant of Sm was constructed successfully which contained a deletion of the htrA and clpP gene without selectable marker. The Cre-loxP(*) system can be applied to Sm, which provides experimental evidence for generating markerless multiple gene deletion mutants.


Assuntos
Deleção de Genes , Genes Bacterianos , Integrases , Streptococcus mutans/genética , Resistência Microbiana a Medicamentos/genética , Regulação Bacteriana da Expressão Gênica , Vetores Genéticos , Integrases/genética , Plasmídeos
13.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 22(6): 371-4, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20594474

RESUMO

OBJECTIVE: To investigate the expression levels of serum soluble Endoglin (sEng), plasma endothelin-1 (ET-1) and coagulation function in patients suffering from early onset severe preeclampsia with organ dysfunction, and to analyze the clinical significance. METHODS: Forty-nine early onset severe preeclampsia patients were enrolled in the study group, including 26 cases without organ dysfunction (study group I) and 23 cases with organ dysfunction (study group II). The control group included 30 cases of health pregnant women during the same period of gestation. The serum levels of sEng and plasma ET-1 were analyzed with enzyme-linked immunosorbent assay (ELISA), coagulation function was determined at the same time, and the relationship between the change in levels of sEng, ET-1, coagulation function and organ function, and also outcome of perinatal infants. RESULTS: (1) The levels of sEng, ET-1, fibrinogen (Fib) and mean platelet volume (MPV) of the study group I and II were significantly higher compared with control group (sEng, microg/L: 10.96+/-3.21, 14.17+/-4.02 vs. 7.49+/-2.73; ET-1, microg/L: 41.54+/-10.37, 65.91+/-12.46 vs. 24.56+/-6.26; Fib, g/L: 4.41+/-1.02, 5.35+/-1.17 vs. 3.69+/-0.82; MPV, fl: 11.71+/-1.21, 13.89+/-1.76 vs. 11.03+/-0.82, all P<0.05), and prothrombin time (PT), activated partial thromboplastin time (APTT) and platelet (PLT) were significantly lower compared with control group (PT, s: 10.73+/-1.82, 8.37+/-1.51 vs. 12.95+/-1.91; APTT, s: 26.14+/-4.32, 22.69+/-3.77 vs. 30.25+/-4.71; PLT, x10(9)/L: 164.17+/-50.67, 136.43+/-51.21 vs. 201.63+/-59.83, all P<0.05). There were also statistical significances in all the values between study group I and II (all P<0.05). (2) There was positive correlation between the sEng level and systolic pressure, diastolic pressure, Fib, urine protein of 24 hours, serum creatinine (SCr); there was negative correlation between the sEng level and albumin (Alb) content, PT, estriol/creatinine (E/C) of 12-hour urine, fetal birth weight (all P<0.01). There was positive correlation between the level of ET-1 and the systolic pressure, diastolic pressure, Fib, urine protein of 24 hours, SCr, or alanine aminotransferase (ALT); there was negative correlation between the level of ET-1 and Alb, PT, E/C of 12-hour urine, or fetal birth weight (P<0.05 or P<0.01). (3)In the study group, the occurrence rate of the heart, kidney and lung dysfunction, placental abruption and perinatal death of infants increased (69.23% vs. 11.11%, 38.46% vs. 2.78%, 38.46% vs. 2.78%, 46.15% vs. 2.78%, 53.85% vs. 2.78%, all P<0.01) when the content of sEng>or=16 microg/L compared with sEng<16 microg/L; the occurrence rate of heart, kidney, liver and lung dysfunction, placental abruption and perinatal death of infants increased (64.28% vs. 11.43%, 35.71% vs. 2.86%, 28.57% vs. 5.71%, 28.57% vs. 5.71%, 35.71% vs. 5.71%, 42.86% vs. 5.71%, all P<0.01) when the level of ET-1>or=70 microg/L compared with ET-1<70 microg/L; the occurrence rate of multiple organ dysfunction syndrome was 90% (9/10) when PT<7 s, APTT<20 s and PLT<100x10(9)/L. CONCLUSION: The elevation of levels of serum sEng, plasma ET-1 and coagulation abnormality may contribute to the pathogenesis of the organ dysfunction in early onset severe preeclampsia, and the detection of the above-mentioned indexes has important clinical value.


Assuntos
Antígenos CD/sangue , Endotelina-1/sangue , Insuficiência de Múltiplos Órgãos/sangue , Pré-Eclâmpsia/sangue , Receptores de Superfície Celular/sangue , Coagulação Sanguínea , Endoglina , Feminino , Humanos , Insuficiência de Múltiplos Órgãos/complicações , Gravidez , Estudos Prospectivos
14.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(1): 37-40, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18380973

RESUMO

OBJECTIVE: To detect the AI-2 quorum-sensing pathway and construct the luxS g-ene allelic exchange plasmid of Streptococcus mutans. METHODS: To detect AI-2 pathway in Streptococcus mutans, the Vibrio harveyi BB170 was used as reporter strain. The PCR fragments of the upstream and downstream regions of luxS and the Erythromycin resistance gene were amplified with the primers respectively, and these fragments were ligated into pUC19 vector with double endonuclease reaction sequentially, the ligated DNAs were transformed into Escherichia coli DH5alpha, then the reconstructed plasmids were isolated and identified by restricted endonuclease digestions. RESULTS: Streptococcus mutans Ingbritt C could induce luminescence of BB170, suggesting the presence of AI-2 quorum sensing pathway in Streptococcus mutans, and such stimulatory activity was maximal at the mid-log growth phase. The recombinant plasmid pUCluxKO was digested by PstI-BamHI, and the digest product were 1000 bp and 5000 bp. When the pUCluxKO was digested by BamHI-KpnI, the digest product were 1500 bp and 4500 bp. While it was digested by KpnI-EcoRI, the digest product were 1000 bp and 5000 bp. All PCR product was in a single belt respectively. CONCLUSIONS: The recombinant plasmid was cloned effectively and can be used in the construction of S.mutans luxS mutant.


Assuntos
Proteínas de Bactérias/genética , Liases de Carbono-Enxofre/genética , Percepção de Quorum/genética , Streptococcus mutans/genética , Regulação Bacteriana da Expressão Gênica , Vetores Genéticos , Homosserina/genética , Plasmídeos
15.
Zhonghua Yi Xue Za Zhi ; 87(12): 802-5, 2007 Mar 27.
Artigo em Chinês | MEDLINE | ID: mdl-17565858

RESUMO

OBJECTIVE: To package recombinant adeno-associated virus-endostatin (rAAV-ES) and study its anti-tumor effect in vitro and in vivo. METHODS: rAAV-ES was packaged with co-transfection technique and transfected into the human bladder cancer cells of the line EJ. 24 h later ELISA was used to examine the concentration of ES in the supernatant. The inhibition of human umbilical veins endothelial cells (HUVECs) chemotactic movement were examined by Transwell system. Nude Balb/c mice were divided into 4 groups: (1) 5 mice were inoculated with the EJ cells transfected with rAAV-ES or rAAV-enhanced yellow fluorescence protein (rAAV-EYFP) for 3 days to the subcutaneous tissues of bilateral shoulders so as to observe the growth of tumor. (2) 24 mice were injected with rAAV-ES intramuscularly and then the serum ES was examined every 10 days since the 10 th day after the injection. (3) 36 mice were randomly subdivided into 3 equal subgroups to be injected with rAAV-ES, rAAV-EYFP, or RPMI medium, inoculated with EJ cells 2 weeks later, and then killed 50 days later to observe the size of tumor. (4) 4 healthy mice and 4 mice injected with rAAV-ES for 8 weeks were killed with their hearts and brains taken out to observe the side effects. RESULTS: rAAV-ES was packaged successfully. The ES concentration in the supernatant of culture fluid of the EJ cell transfected with rAAV-ES was 54.09 ng/ml. The inhibition rate of the HUVECs chemotactic movement was 37.45%. The xenograft formation rate was 2/5 for the EJ cells transfected with rAAV-ES. The serum ES levels of the mice injected with rAAV-ES remained high. The tumor size in the mice injected with rAAV-ES was significantly smaller than those of the other groups (both P < 0.01). No pathological changes was found in the hearts and brains in the mice injected with rAAV-ES. CONCLUSION: rAAV-ES inhibits tumor angiogenesis, and tumor formation and progression. Successful packaging of rAAV-ES has laid a foundation for gene therapy of bladder cancer.


Assuntos
Dependovirus/genética , Endostatinas/fisiologia , Terapia Genética , Neoplasias da Bexiga Urinária/terapia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Endostatinas/sangue , Endostatinas/genética , Vetores Genéticos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/patologia , Neovascularização Patológica/prevenção & controle , Distribuição Aleatória , Transfecção , Carga Tumoral , Neoplasias da Bexiga Urinária/irrigação sanguínea , Neoplasias da Bexiga Urinária/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
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