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1.
ACS Appl Mater Interfaces ; 13(5): 6156-6167, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33507065

RESUMO

Li-CO2 batteries have recently attracted attention as promising candidates for next-generation energy storage devices due to their extremely high theoretical energy density. The real application of Li-CO2 cells involves addressing several drawbacks, including high charging potential, poor coulombic efficiency, and low rechargeability. Molybdenum disulfide supported on carbon nanotubes (MoS2/CNT) with various ratios functioned as a cathode catalyst for Li-CO2 batteries. The optimal MoS2/CNT composite achieved a maximum discharge capacity of 8551 mAh g-1 with a coulombic efficiency of 96.7%. This hybrid also obtained an initial charging plateau of 3.87 V at a current density of 100 mA g-1 with a cutoff capacity of 500 mAh g-1. It provided ideal electrochemical stability of 142 cycles at the current densities of 100 mA g-1, which was comparable with that of some precious metal catalysts. This optimized MoS2/CNT was also cycled at 200 and 400 mA g-1 for 112 and 55 times, respectively. Density functional theory calculations demonstrated that the sulfided Mo-edge (s-Mo-edge) on MoS2 materials showed appropriate adsorption strengths of Li, CO2, and Li2CO3. Moreover, joint results of Raman profiles and extended X-ray absorption fine structure spectra elucidated that the catalytic efficiencies of MoS2/CNT hybrids were proportional to the quantities of exposed s-Mo-edge active sites.

2.
Nutr Cancer ; 67(3): 392-400, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706900

RESUMO

This meta-analysis was conducted to assess the association between coffee consumption and prostate cancer risk. Thirteen cohort studies with 34,105 cases and 539,577 participants were included in the meta-analysis. The summary relative risks (RRs) with 95% confidence intervals (CIs) for different coffee intake levels were calculated. Dose-response relationship was assessed using generalized least square trend estimation. The pooled RR for the highest vs. lowest coffee intake was 0.90 (95% CI: 0.85-0.95), with no significant heterogeneity across studies (P = 0.267; I(2) = 17.5%). The dose-response analysis showed a lower cancer risk decreased by 2.5% (RR = 0.975; 95% CI: 0.957-0.995) for every 2 cups/day increment in coffee consumption. Stratifying by geographic region, there was a statistically significant protective influence of coffee on prostate cancer risk among European populations. In subgroup analysis of prostate cancer grade, the summary RRs were 0.89 (95% CI: 0.83-0.96) for nonadvanced, 0.82 (95% CI: 0.61-1.10) for advanced and 0.76 (95% CI: 0.55-1.06) for fatal diseases. Our findings suggest that coffee consumption may be associated with a reduced risk of prostate cancer and it also has an inverse association with nonadvanced prostate cancer. Because of the limited number of studies, more prospective studies with large sample size are needed to confirm this association.


Assuntos
Café , Neoplasias da Próstata/prevenção & controle , Estudos de Coortes , Humanos , Masculino , Neoplasias da Próstata/etiologia , Viés de Publicação , Risco
3.
Eur J Cancer Prev ; 24(6): 508-16, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25642791

RESUMO

This meta-analysis was conducted to assess the association between fruit and vegetable intake and bladder cancer risk. Eligible studies published up to August 2014 were retrieved both through a computer search of PubMed, Embase and the Cochrane library and through a manual review of references. The summary relative risks with 95% confidence intervals (CIs) for the highest versus the lowest intakes of fruits and vegetables were calculated with random-effects models. Heterogeneity and publication bias were also evaluated. Potential sources of heterogeneity were detected with metaregression. Subgroup analyses and sensitivity analyses were also performed. A total of 27 studies (12 cohort and 15 case-control studies) were included in this meta-analysis. The summary relative risks for the highest versus lowest were 0.84 (95% CI: 0.72-0.96) for vegetable intake and 0.81 (95% CI: 0.73-0.89) for fruit intake. The dose-response analysis showed that the risk of bladder cancer decreased by 8% (relative risk=0.92; 95% CI: 0.87-0.97) and 9% (relative risk=0.91; 95% CI: 0.83-0.99) for every 200 g/day increment in vegetable and fruit consumption, respectively. Sensitivity analysis confirmed the stability of the results. Our findings suggest that intake of vegetables and fruits may significantly reduce the risk of bladder cancer. Further well-designed prospective studies are warranted to confirm these findings.


Assuntos
Dieta , Frutas , Neoplasias da Bexiga Urinária/prevenção & controle , Verduras , Comportamento Alimentar , Humanos , Estudos Observacionais como Assunto
4.
Int J Clin Exp Med ; 7(11): 3954-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25550903

RESUMO

Previous studies have investigated the relationship between oral contraceptives (OCs) use and kidney cancer risk. However, they yielded inconsistent results. To our knowledge, a comprehensive assessment of the association between OC and kidney cancer risk has not been reported. Hence, we conducted a meta-analysis to quantify the association. We identified all relevant studies up to July 2014 through a literature search of using PubMed and EMBASE, and by reviewing the references from the retrieved articles. Fixed-effect and random-effect models were used to estimate summary relative risks (SRRs) and the corresponding 95% confidence intervals (CIs). A total of 12 studies were eligible and included in this meta-analysis, involving 4,206 kidney cancer cases and 638,677 participants. The SRR of kidney cancer for ever versus never OC use was 0.89 (95% CI: 0.82-0.98). The protection became stronger when compared the longest duration of OC use with never use (RR = 0.80; 95% CI: 0.68-0.94). In dose-response analysis, we found that the kidney cancer risk decreased by 2% for per 1 year increment in OC use (RR = 0.98; 95% CI: 0.96-0.99). No apparent heterogeneity was observed across studies included in this analysis. Egger's and Begg's test also indicated no publication bias. The present study suggested that OC may reduce the risk of kidney cancer, especially for long-term users. More well-conducted and large-scale prospective studies are warranted to confirm the effects of OC use on kidney cancer.

5.
Chin J Cancer ; 29(2): 212-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20109354

RESUMO

BACKGROUND AND OBJECTIVE: Primary renal synovial sarcoma is rare and might be misdiagnosed as another renal tumor. This study demonstrates the clinicopathologic and immunohistochemical features, differential diagnosis, and prognosis of such tumors. METHODS: Histologic slides and clinical data were reviewed for 4 patients with primary renal synovial sarcoma and immunohistochemical staining was performed. Molecular analysis was performed on 2 cases to demonstrate the presence of the SYT-SSX gene fusion transcripts by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The patients were 2 women and 2 men aged from 32 to 48 years. The tumors were 10.0-15.0 cm in diameter, grey-white and solid, and hemorrhage or necrosis was observed. Microscopically, the tumors consisted of mitotically active, monomorphic plump spindle cells with indistinct cell borders growing in short, intersecting fascicles. Hypocellular myxoid areas and a prominent hemangiopericytomatous pattern were present in all cases. The average mitotic rate was 5-8 mitoses/10 high-power fields. Hemorrhage and tumor necrosis were easily found. Scattered small cysts lined with flat, cuboidal, or hobnailed epithelia were found in 3 cases. Tumor cells are immunoreactive for Vimentin (4/4), Bcl-2 (4/4), CD99 (4/4), and CD56 (3/4), and focally for EMA (3/4) and Cytokeratin (3/4). SYT-SSX1 gene fusion was detected in the 2 cases in which RT-PCR analysis was performed. One patient had tumor metastasis to the lung 6 months after surgery and died 5 months later. Multiple metastasis to the liver occurred in one patient and the patient died 13 months after the initial surgery. The other 2 patients had tumors recur at 8 and 15 months and died at 18 and 21 months, respectively, after the initial operation. CONCLUSION: Primary renal synovial sarcoma is rare, with poor prognosis, characterized by SYT-SSX gene fusion, and needs to be differentiated from other renal sarcomas.


Assuntos
Neoplasias Renais/cirurgia , Nefrectomia , Proteínas de Fusão Oncogênica/metabolismo , Sarcoma Sinovial/cirurgia , Antígeno 12E7 , Adulto , Antígenos CD/metabolismo , Antígeno CD56/metabolismo , Moléculas de Adesão Celular/metabolismo , Feminino , Seguimentos , Humanos , Queratinas/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Mucina-1/metabolismo , Recidiva Local de Neoplasia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sarcoma Sinovial/metabolismo , Sarcoma Sinovial/patologia , Sarcoma Sinovial/secundário , Taxa de Sobrevida , Vimentina/metabolismo
6.
Yi Chuan Xue Bao ; 32(10): 1082-8, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16252704

RESUMO

Using an estrogen-inducible expression XVE (LexA-VP16-Estragon Receptor) system, we have generated approximately 40 000 independent T-DNA insertion lines of Arabidopsis thaliana. Segregation analyses of about 18000 lines indicated that 51.6% of them contain single T-DNA insertions and that the average insertion number is 1.38 copies per line. Mutants displaying a variety of morphological alterations were identified, including those that affect development of roots,hypocotyls, leaves, floral organs and seeds as well as the flowering time.


Assuntos
Arabidopsis/genética , DNA Bacteriano/genética , Mutagênese Insercional/métodos , Plantas Geneticamente Modificadas/genética , Arabidopsis/anatomia & histologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Clonagem Molecular , Estrogênios/farmacologia , Vetores Genéticos/genética , Proteína Vmw65 do Vírus do Herpes Simples/genética , Mutagênese Insercional/efeitos dos fármacos , Fenótipo , Plantas Geneticamente Modificadas/anatomia & histologia , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plasmídeos/genética , Receptores de Estrogênio/genética , Serina Endopeptidases/genética , Ativação Transcricional/efeitos dos fármacos
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