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1.
Small Methods ; : e2400258, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38962863

RESUMO

Nanoengineering polar oxide films have attracted great attention in energy storage due to their high energy density. However, most of them are deposited on thick and rigid substrates, which is not conducive to the integration of capacitors and applications in flexible electronics. Here, an alternative strategy using van der Waals epitaxial oxide dielectrics on ultra-thin flexible mica substrates is developed and increased the disorder within the system through high laser flux. The introduction of defects can efficiently weaken or destroy the long-range ferroelectric ordering, ultimately leading to the emergence of a large numbers of weak-coupling regions. Such polarization configuration ensures fast polarization response and significantly improves energy storage characteristics. A flexible BiFeO3-BaTiO3 (BF-BT) capacitor exhibits a total energy density of 43.5 J cm-3 and an efficiency of 66.7% and maintains good energy storage performance over a wide temperature range (20-200 °C) and under large bending deformation (bending radii ≈ 2 mm). This study provides a feasible approach to improve the energy storage characteristics of dielectric oxide films and paves the way for their practical application in high-energy density capacitors.

2.
ACS Appl Mater Interfaces ; 14(32): 36825-36833, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35929806

RESUMO

Ferroelectric solid solutions with composition near the morphotropic phase boundary (MPB) have gained extensive attention recently due to their excellent ferroelectric and piezoelectric properties. Here, we have demonstrated a strategy to realize the controllable preparation of BiFeO3-BaTiO3 (BF-BT) epitaxial films near the MPB. A series of high-quality BF-BT films were fabricated by pulsed laser deposition via adjusting oxygen partial pressure (PO2) using a BF-BT ceramic target. A continuous transition from rhombohedral to tetragonal phase was observed upon increasing PO2. Particularly, the film with a pure tetragonal phase exhibited a large remnant polarization of ∼90.6 µC/cm2, while excellent piezoelectric performance with an ultrahigh strain (∼0.48%) was obtained in the film with coexisting rhombohedral and tetragonal phases. The excellent ferroelectric and piezoelectric properties endow the BF-BT system near the MPB with great application prospects in lead-free electronic devices.

3.
Mol Med Rep ; 10(4): 2160-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25070000

RESUMO

Small non­coding RNAs from the microRNA family (miRs) are important elements in the posttranscriptional control of gene expression. miRs are known to regulate numerous cellular processes and are of crucial importance during development and in pathological conditions, including tumor initiation and progression. In the present study, the expression level of miR­181 was reduced in glioma tissues compared with the adjacent normal tissues. The enforced expression of miR­181 was able to inhibit cell proliferation in U251 and SHG­44 cells, while antisense miR­181 oligonucleotides (antisense miR­181) enhanced cell proliferation. At the molecular level, these results further revealed that the expression of cyclin B1, a positive cell­cycle regulator, was negatively regulated by miR­181. Therefore, the data reported in the present study demonstrates that miR­181 is an important regulator in glioma. These results may contribute to improving the understanding of the key misregulated miRNAs in glioma.


Assuntos
Neoplasias Encefálicas/patologia , Ciclina B1/metabolismo , Glioma/patologia , MicroRNAs/metabolismo , Regiões 3' não Traduzidas , Sequência de Bases , Encéfalo/metabolismo , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Ciclina B1/química , Ciclina B1/genética , Glioma/metabolismo , Humanos , MicroRNAs/antagonistas & inibidores , Oligonucleotídeos Antissenso/metabolismo , Alinhamento de Sequência
4.
Tumour Biol ; 35(7): 6687-93, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24705863

RESUMO

We conducted a meta-analysis in order to investigate the relationships between PTEN gene mutations and the prognosis in glioma. The following electronic databases were searched for relevant articles without any language restrictions: Web of Science (1945 ~ 2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966 ~ 2013), EMBASE (1980 ~ 2013), CINAHL (1982 ~ 2013), and the Chinese Biomedical Database (CBM) (1982 ~ 2013). Meta-analyses were conducted using the STATA software (Version 12.0, Stata Corporation, College Station, Texas USA). Hazard ratio (HR) with its corresponding 95 % confidence interval (95%CI) was calculated. Six independent cohort studies with a total of 357 glioma patients met our inclusion criteria. Our meta-analysis results indicated that glioma patients with PTEN gene mutations exhibited a significantly shorter overall survival (OS) than those without PTEN gene mutations (HR = 3.66, 95%CI = 2.02 ~ 5.30, P < 0.001). Ethnicity-stratified subgroup analysis demonstrated that PTEN gene mutations were closely linked to poor prognosis in glioma among Americans (HR = 3.72, 95%CI = 1.72 ~ 5.73, P < 0.001), while similar correlations were not observed among populations in Sweden, Italy, and Malaysia (all P > 0.05). Our meta-analysis provides direct and strong evidences for the speculation of PTEN gene mutations' correlation with poor prognosis of glioma patients.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias Encefálicas/patologia , Predisposição Genética para Doença , Glioma/patologia , Humanos , Mutação , Prognóstico
5.
PLoS One ; 9(2): e87432, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24586276

RESUMO

BACKGROUND: Although international guideline recommended routine intracranial pressure (ICP) monitoring for patients with severe traumatic brain injury(TBI), there were conflicting outcomes attributable to ICP monitoring according to the published studies. Hence, we conducted a meta-analysis to evaluate the efficacy and safety of ICP monitoring in patients with TBI. METHODS: Based on previous reviews, PubMed and two Chinese databases (Wangfang and VIP) were further searched to identify eligible studies. The primary outcome was mortality. Secondary outcomes included unfavourable outcome, adverse events, length of ICU stay and length of hospital stay. Weighted mean difference (WMD), odds ratio (OR) and 95% confidence intervals (CIs) were calculated and pooled using fixed-effects or random-effects model. RESULTS: two randomized controlled trials (RCTs) and seven cohort studies involving 11,038 patients met the inclusion criteria. ICP monitoring was not associated with a significant reduction in mortality (OR, 1.16; 95% CI, 0.87-1.54), with substantial heterogeneity (I(2) = 80%, P<0.00001), which was verified by the sensitivity analyses. No significant difference was found in the occurrence of unfavourable outcome (OR, 1.40; 95% CI, 0.99-1.98; I(2) = 4%, P = 0.35) and adverse events (OR, 1.04; 95% CI, 0.64-1.70; I(2) = 78%, P = 0.03). However, we should be cautious to the result of adverse events because of the substantial heterogeneity in the comparison. Furthermore, longer ICU and hospital stay were the consistent tendency according to the pooled studies. CONCLUSIONS: No benefit was found in patients with TBI who underwent ICP monitoring. Considering substantial clinical heterogeneity, further large sample size RCTs are needed to confirm the current findings.


Assuntos
Lesões Encefálicas/patologia , Pressão Intracraniana/fisiologia , Monitorização Fisiológica/efeitos adversos , Monitorização Fisiológica/mortalidade , Monitorização Fisiológica/métodos , Humanos , Tempo de Internação/estatística & dados numéricos , Modelos Estatísticos , Razão de Chances
6.
Zhonghua Nei Ke Za Zhi ; 51(2): 131-5, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22490815

RESUMO

OBJECTIVE: To determine the distribution of vitamin D receptor (VDR) gene ApaI and BsmI polymorphism in systemic lupus erythematosus (SLE) and the association with SLE in Chinese Han patients. METHODS: Genomic DNA from 244 Chinese SLE patients and 162 sex and ethnically matched controls were typed for VDR ApaI and BsmI polymorphism combination by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Clinical characteristics were analyzed between different ApaI and BsmI genotypes. RESULTS: There was no significant difference between the distribution frequencies of allelic gene A and a in SLE patients and the controls, but the distribution frequency of genotypes heterozygote Aa in SLE patients was higher than that in the controls (38.9% vs 22.2%, χ(2) = 12.442, P = 0.000). There was no significant difference between the distribution frequency of allelic gene and genotypes of BsmI in SLE patients and the controls (P > 0.05). However, there was significant difference between the distribution frequencies of ApaI and BsmI genotypes combination in SLE patients and the controls (χ(2) = 18.226, P = 0.006). The distribution frequency of genotypes Aa-bb in SLE patients was higher than that in the controls (32.4% vs 17.9%, χ(2) = 10.449 P = 0.001), while the distribution frequency of genotypes Aa-bb in SLE patients was lower than that in the controls (30.3% vs 42.0%, χ(2) = 5.808, P = 0.016). Furthermore, analyzing the effect of VDR ApaI and BsmI polymorphism combination to the symptoms of SLE, significant difference was observed in SLE patients carrying Aa-bb genotypes involved in serositis (P = 0.003), hematological system disorder (P = 0.021), and anti-Sm antibodies (P = 0.01) compared with other genotypes. CONCLUSION: There is significant association between ApaI and BsmI gene polymorphism Aa-bb genotypes and the incidence of SLE in the Han population of China, and genotype Aa-bb is more involved in serositis, hematological system disorder and has a positive effect on production of antibodies.


Assuntos
Lúpus Eritematoso Sistêmico/genética , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Adolescente , Adulto , Idoso , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 27(8): 901-5, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21806892

RESUMO

AIM: To investigate the relationship of vitamin D receptor (VDR) gene Fok I polymorphism with systemic lupus erythematosus (SLE) and to observe VDR mRNA levels in Chinese Han SLE patients. METHODS: Genomic DNAs from 271 Chinese SLE patients and 130 healthy controls were determined for Fok I polymorphism by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), and VDR mRNA levels from 48 Chinese SLE patients and 38 healthy controls were detected by real-time polymerase chain reaction (RT-PCR). RESULTS: Gene frequencies of allelic F and f were significantly different between the SLE patients and the controls (P=0.001).The relative risk of SLE in the presence of allelic gene F was 1.630 (95%CI=1.210-2.196, P=0.001). The frequency of homozygote FF in the SLE patients was higher than that in the controls (42.8% vs 25.4%, x(2);=11.417, P=0.001). Serositis, anti-dsDNA antibody, anti-Sm antibody and anti-histone antibody in the SLE patients carrying homozygote FF and heterozygote Ff were higher than those in the SLE patients carrying homozygote ff (P=0.001, P=0.001, P=0.047, P=0.001, respectively). The VDR mRNA was decreased in the SLE patients, with a delta;Ct value of 9.26 ± 2.37 (P=0.026), as compared with a delta;Ct value of 7.82 ± 3.05 in the controls (the bigger of the delta;Ct value, the lower of VDR mRNA expression). The delta;Ct value of VDR mRNA in the SLE patients carrying FF and Ff was bigger than that in the SLE patients carrying ff (10.54 ± 1.88 vs 7.15 ± 3.78, P=0.019). CONCLUSION: VDR gene Fok I polymorphism is associated with SLE in the Han population of southern China. The SLE patients carrying F allel ± are more likely to have serositis and produce anti-dsDNA antibody, anti-Sm antibody and anti-Histone antibody, presumably as a result of down-regulation of VDR mRNA.


Assuntos
Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Receptores de Calcitriol/genética , Adolescente , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores de Calcitriol/metabolismo , Adulto Jovem
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 19(3): 734-7, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-21729561

RESUMO

This study was purposed to investigate the mechanism of thrombocytopenia in patients with systemic lupus erythematosus (SLE) through detecting anti-megakaryocyte antibodies in SLE patients. The serum anti-megakaryocyte antibodies in 36 SLE cases with thrombocytopenia were detected by using indirect immunofluorescence, the detected results were compared with detected results of 30 SLE cases without thrombocytopenia and 30 healthy persons. The results showed that the positive incidences of anti-megakaryocyte antibody in serum of 36 SLE cases with thrombocytopenia, 30 SLE cases without thrombocytopenia and 30 healthy persons were 19.4% (7/36), 6.7% (2/30) and 3.3% (1/30) respectively. As compared with SLE patients without thrombocytopenia and healthy persons, SLE patients with thrombocytopenia had higher incidence of anti-megakaryocyte antibodies, moreover there was significant difference between SLE patients with thrombocytopenia and healthy persons (p < 0.05), while there was no significant difference between SLE patients with or without thrombocytopenia (p > 0.05). It is concluded that autoantibodies against megakaryocytes exist in SLE patients and may partially contribute to the incidence of thrombocytopenia in SLE patients. The detection of anti-megakaryocyte antibodies with a enough case number is needed to make a final conclusion on thrombocytopenia pathogenesis in SLE.


Assuntos
Autoanticorpos/sangue , Lúpus Eritematoso Sistêmico/sangue , Megacariócitos/imunologia , Adulto , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade
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