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1.
Small ; 20(15): e2306753, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37994254

RESUMO

Photosensitive supercapacitors incorporate light-sensitive materials on capacitive electrodes, enabling solar energy conversion and storage in one device. In this study, heterogeneous structures of rod-shaped ZnO decorated with Ce2S3 nanoparticles on nickel foam (ZnO@Ce2S3/NF) are synthesized using a two-step hydrothermal method as photosensitive supercapacitor electrodes for capacitance enhancement under visible light. The formation of ZnO@Ce2S3 heterogeneous structures is confirmed using various structural characterization techniques. The area-specific capacitance of the ZnO@Ce2S3/NF composite electrode increased from 1738.1 to 1844.0 mF cm-2 after illumination under a current density of 5 mA cm-2, which is 2.4 and 2.8 times higher than that of ZnO and Ce2S3 electrodes under similar conditions, respectively, indicating the remarkable light-induced capacitance enhancement performance. The ZnO@Ce2S3/NF electrode also exhibits a higher photocurrent and photovoltage than the two single electrodes, demonstrating its excellent photosensitivity. The improved capacitance performance and photosensitivity under illumination are attributed to the well-constructed energy-level structure, which stimulates the flow of photogenerated electrons from the outer circuit and the involvement of photogenerated holes in the resulting surface-controlled capacitance. In addition, the assembled ZnO@Ce2S3/NF-based hybrid supercapacitor exhibits a great energy density of 145.0 mWh cm-2 under illumination. This study provides a novel strategy for the development of high-performance solar energy conversion/storage devices.

2.
Materials (Basel) ; 16(14)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37512199

RESUMO

2 at.% Cu + 2 at.% Ni were co-doped in ZnO nanoparticles by a simple hydrothermal method, and then the modified nanoparticles were compounded into Cu-Ni alloy coatings using an electroplating technique. The effects of the current density (15-45 mA/cm2) on the phase structure, surface morphology, thickness, microhardness, corrosion resistance, and photocatalytic properties of the coatings were investigated. The results show that the Cu-Ni-Zn0.96Ni0.02Cu0.02O nanocomposite coatings had the highest compactness and the best overall performance at a current density of 35 mA/cm2. At this point, the co-deposition rate reached its maximum, resulting in the deposition of more Zn0.96Ni0.02Cu0.02O nanoparticles in the coating. More nanoparticles were dispersed in the coating with a better particle strengthening effect, which resulted in a minimum crystallite size of 15.21 nm and a maximum microhardness of 558 HV. Moreover, the surface structure of the coatings became finer and denser. Therefore, the corrosion resistance was significantly improved with a corrosion current density of 2.21 × 10-3 mA/cm2, and the charge transfer resistance was up to 20.98 kΩ·cm2. The maximum decolorization rate of the rhodamine B solution was 24.08% under ultraviolet light irradiation for 5 h. The improvement in the comprehensive performance was mainly attributed to the greater concentration of Zn0.96Ni0.02Cu0.02O nanoparticles in the coating, which played the role of the particle-reinforced phase and reduced the microstructure defects.

3.
Materials (Basel) ; 16(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37049041

RESUMO

Here, 2% Cu + 2% Ni co-doped ZnO nanoparticles were synthesized using the hydrothermal method and were used as particle reinforcements of Cu-Ni nanocomposite coatings prepared by electroplating technology. The effects of the added (Cu, Ni) co-doped ZnO nanoparticles (2-8 g/L) on the phase structure, surface morphology, thickness, microhardness, corrosion resistance, and photocatalytic properties of the coatings were investigated. The nanocomposite coatings have obvious diffraction peaks on the crystal planes of (111), (200), and (220), showing a wurtzite structure. The surface of the nanocomposite coatings is cauliflower-like, and becomes smoother and denser with the increase in the addition of nanoparticles. The grain size, thickness, microhardness, corrosion resistance, and photocatalytic properties of the nanocomposite coating reach a peak value when the added (Cu, Ni) co-doped ZnO nanoparticles are 6 g/L. At this concentration, the mean crystallite size of the coating reaches a minimum of 15.31 nm, and the deposition efficiency of the coating is the highest. The (Cu, Ni) co-doped ZnO nanoparticle reinforcement makes the microhardness reach up to 658 HV. The addition of nanoparticles significantly improves the corrosion resistance and photocatalytic properties of nanocomposite coatings. The minimum corrosion current density is 2.36 × 10-6 A/cm2, the maximum corrosion potential is -0.301 V, and the highest decolorization rate of Rhodamine B is 28.73% after UV irradiation for 5 h.

4.
BMC Cancer ; 23(1): 127, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750774

RESUMO

BACKGROUND: Metastasis of cancer causes more than 90% of cancer deaths and is severely damaging to human health. In recent years, several studies have linked sarcopenia to shorter survival in patients with metastatic cancer. Several predictive models exist to predict mortality in patients with metastatic cancer, but have reported limited accuracy. METHODS: We systematically searched Medline, EMBASE, and the Cochrane Library for articles published on or before October 14, 2022. Pooled Hazard Ratio (HR) estimates with 95% confidence intervals (CIs) were calculated using a random effects model. The primary outcome was an increased risk of death or tumor progression in patients with metastatic cancer, which is expressed as progression-free survival (PFS). In addition, we performed subgroup analyses and leave-one-out sensitivity analyses to explore the main sources of heterogeneity and the stability of the results. RESULTS: Sixteen retrospective cohort studies with 1,675 patients were included in the 888 papers screened. The results showed that sarcopenia was associated with lower progression-free survival (HR = 1.56, 95% CI = 1.19-2.03, I2 = 76.3%, P < 0.001). This result was further confirmed by trim-and-fill procedures and leave-one-out sensitivity analysis. CONCLUSIONS: This study suggests that sarcopenia may be a risk factor for reduced progression-free survival in patients with metastatic cancer. Further studies are still needed to explain the reason for this high heterogeneity in outcome. TRIAL REGISTRATION: CRD42022325910.


Assuntos
Sarcopenia , Humanos , Intervalo Livre de Progressão , Estudos Retrospectivos , Fatores de Risco
5.
Front Bioeng Biotechnol ; 10: 890118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36082162

RESUMO

Objective: The unicondylar knee arthroplasty (UKA) procedure is primarily indicated for osteoarthritis of the knee. Anterior cruciate ligament (ACL) defects have long been considered a contraindication to UKA. However, recent clinical studies have found that ACL defects do not affect postoperative outcomes in UKA. To elucidate whether ACL defects affect postoperative outcomes in UKA, we performed a systematic review and Meta-analysis of observational cohort studies comparing the effects of ACL defects and intactness on surgical outcomes in UKA. Methods: In this study, we used "Anterior Cruciate Ligament", "Anterior Cruciate Ligament Injuries" and "Arthroplasty, Replacement, Knee" as the subject terms according to PICOS principles. These subject terms and the corresponding free texts were used to conduct a systematic search in the three major databases PubMed, Embase and Cochrane on December 9, 2021. The main study variables included age, gender, region, definition of ACL defect and diagnosed diseases. The study used a random effect model to pool the effect of 95% CIs. To explore the sources of heterogeneity and to test the stability of the results, a sensitivity analysis was performed. Results: The systematic review found no significant differences in postoperative clinical outcomes in the elderly population when unicondylar replacement was performed in the setting of multiple factors such as injury, defects, longitudinal tear, and synovial bursa injury defined as ACL deficiency. The primary clinical outcomes included postoperative revision, Tegner activity score, and Oxford Knee Score (OKS). After statistical meta-analysis, postoperative outcomes such as postoperative revision (OR, 1.174; 95% CIs, 0.758-1.817) and Tegner activity score (OR, -0.084; 95% CIs, -0.320-0.151) were not statistically different. Conclusion: There was no difference in postoperative revision rates and functional outcomes such as Tegner activity score between the ACL-deficient group compared with the ACL-intact group. For the present results, it is not advisable to consider ACL deficiency as a contraindication of UKA.

6.
J Agric Food Chem ; 70(28): 8513-8522, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35816106

RESUMO

Soil heavy-metal pollution leads to excessive heavy metals in rice and other food crops, which has caused serious impacts on the ecological environment and on human health. In recent years, environmental friendly treatment methods that reduce the bioavailability of heavy metals in soil by soil microorganisms improving the tolerance of heavy metals in rice and reducing the transfer of heavy metals from the roots to the above-ground parts of rice have attracted much attention. This paper reviews the role and mechanism of soil microorganisms in alleviating heavy-metal stress in rice at home and abroad in recent years. At present, microorganisms tolerant to heavy metals mainly include bacteria and fungi, and their mechanisms include the adsorption of heavy metals by microorganisms, the secretion of growth-promoting substances (growth hormone, ACC deaminase, IAA), changing the physical and chemical properties of the soil and the composition of the microbial community, changing the transport mode of heavy metals in soil, the improvement of the antioxidant capacity of rice, etc. Hence, soil microorganisms have good application value and prospects in rice and other crops. However, the vast majority of current research focuses on a single strain, the screening principles of strains are limited, the pathogenicities of the strains have not been evaluated, and there are still few field experiments under natural conditions. In the future, we should strengthen the action of soil microorganisms on rice in response to the above problems in heavy metals, to better promote the microbial remediation technology.


Assuntos
Metais Pesados , Microbiota , Oryza , Poluentes do Solo , China , Produtos Agrícolas , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Oryza/fisiologia , Solo/química , Poluentes do Solo/análise
7.
Front Neurosci ; 16: 903472, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860297

RESUMO

Neurological disorders cause untold human disability and death each year. For most neurological disorders, the efficacy of their primary treatment strategies remains suboptimal. Microglia are associated with the development and progression of multiple neurological disorders. Targeting the regulation of microglia polarization has emerged as an important therapeutic strategy for neurological disorders. Their pro-inflammatory (M1)/anti-inflammatory (M2) phenotype microglia are closely associated with neuronal apoptosis, synaptic plasticity, blood-brain barrier integrity, resistance to iron death, and astrocyte regulation. LncRNA, a recently extensively studied non-coding transcript of over 200 nucleotides, has shown great value to intervene in microglia polarization. It can often participate in gene regulation of microglia by directly regulating transcription or sponging downstream miRNAs, for example. Through proper regulation, microglia can exert neuroprotective effects, reduce neurological damage and improve the prognosis of many neurological diseases. This paper reviews the progress of research linking lncRNAs to microglia polarization and neurological diseases.

8.
Front Oncol ; 12: 864501, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480101

RESUMO

Background: As a metastasis cancer that happens up to 70% of the cancer patients, spinal metastasis is drawing attention for its significant impairment to health. There exist several predictive models designed to estimate mortality in spinal metastasis patients but they are reported with limited accuracy. In recent years, some retrospective cohort studies have been carried out to associate sarcopenia with mortality in spinal metastasis. Introduction: As a risk factor leading to adverse events in many diseases, sarcopenia was considered to significantly impact on patients with spinal metastasis in mortality by some scientists. We aimed to look through the current evidence and use statistic measures to value the role of sarcopenia in spinal metastasis. In this study, we are going to perform a systematic review and meta-analysis of available retrospective cohort studies where sarcopenia is assessed for outcomes in spinal metastasis patients. Methods: On October 7, 2021, we performed a search in PubMed, Embase, and the Cochrane Library. We set no restrictions on language, date or areas. Results were expressed as hazard ratio (HR) or odds ratio (OR) with 95% CI by random effects model. Sensitivity analyses were performed to explore sources of heterogeneity and stability of results. Results: Of the 4,196 papers screened, 10 retrospective cohort studies were included, with a total of 1,674 patients. Results showed that sarcopenia was associated with higher overall mortality (OR, 1.60; 95% CI 1.35-1.90) and lower overall survival (HR, 2.08; 95% CI 1.55-2.80). The sensitivity analysis proved the stability of results in terms of publication years, region, time of diagnosis, sample size, female rate, measurement and follow up period. Conclusions: Sarcopenia is a robust indicator of mortality in spinal metastasis patients and it might be applied to decision-making tools to assess survival probability and adjust the extent of treatment, while a lack of higher level of evidence is existing. Systematic Review Registration: PROSPERO CRD42021283348.

9.
PLoS One ; 17(3): e0264268, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35275924

RESUMO

BACKGROUND: Sarcopenia is a progressive age-related skeletal muscle disorder characterized by decreased muscle mass and loss of muscle function. Recent studies have shown that sarcopenia is able to predict a variety of clinical outcomes after spinal surgery. Controversy still exists among previous reports in terms of the definition and measurement of sarcopenia, these findings are heterogeneous so far. Therefore, the aim of the current study is to assess the up-to-date evidence of sarcopenia for postoperative outcomes among people undergoing spinal surgery. METHODS AND ANALYSIS: This protocol was carried out based on the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) statement. It has been pre-registered in PROSPERO with the registration number of CRD42021260459. Three databases (including Pubmed, EMBASE, and Cochrane Library) will be searched from inception through May 10, 2021 to determine related cohort studies examining sarcopenia on multidimensional outcomes in patients undergoing spinal surgery. Major outcomes will be involved including mortality, morbidity, length of stay, postoperative complications or adverse events. DerSimonian & Laird random-effects meta-analysis will be used to calculate pooled odds ratio (OR) for binary data and pooled weighted mean differences (WMDs) or standardized mean differences (SMDs) for continuous data. The Newcastle-Ottawa Scale (NOS) will be used to assess the risk of bias of included studies. Narrative synthesis will be carried out if a pooled analysis is not possible. ETHICS AND DISSEMINATION: Ethical approval is not required for this study as the data involved are from the published literatures. We intend to disseminate or share the results of the study in a peer-reviewed journal or at relevant conferences. PROSPERO REGISTRATION NUMBER: CRD42021260459.


Assuntos
Sarcopenia , Humanos , Metanálise como Assunto , Morbidade , Período Pós-Operatório , Projetos de Pesquisa , Sarcopenia/complicações , Revisões Sistemáticas como Assunto
10.
Adv Ther ; 39(5): 2151-2164, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35294737

RESUMO

INTRODUCTION: Bupivacaine is a more widely used anesthetic than mepivacaine. However, the long-acting effects of bupivacaine often lead to slow and unpredictable return. As an intermediate-acting local anesthetic, mepivacaine can enable earlier ambulation and thus has other benefits. We performed a systematic review and meta-analysis of available randomized controlled trials (RCTs) comparing the anesthetic effects of mepivacaine and bupivacaine. METHODS: On August 12, 2021, a search was performed in PubMed, Embase, and the Cochrane Library. Effect estimates with 95% CI were combined using a random effects model. We performed sensitivity analyses to explore sources of heterogeneity and stability of results. RESULTS: Of the 406 papers screened, 14 population-based randomized controlled trials were included, with a total of 1007 patients. Overall, compared to bupivacaine, mepivacaine was associated with higher numbers of motor block 3 (OR, 4.05; 95% CI 1.92-8.57), shorter length of stay (SMD, - 0.77; 95% CI - 1.52 to - 0.03), faster recovery from motor block (SMD, - 1.45; 95% CI - 2.39 to - 0.51), and shorter time to return to voiding (SMD, - 1.24; 95% CI - 1.83 to - 0.64). Mepivacaine was associated with a higher incidence of transient neurologic symptoms (TNS) and transient nerve root irritation (TRI) (OR, 9.18; 95% CI 2.42-34.88). There was no statistical difference between the two anesthetics in terms of pain index on the postoperative day (SMD, 0.20; 95% CI - 0.06 to 0.46) and incidence of urinary retention (OR, 0.98; 95% CI 0.47-2.03). CONCLUSIONS: Mepivacaine may have advantages over bupivacaine in terms of achieving motor block 3, shorter length of stay, earlier recovery from motor block, and earlier time to return to voiding, but it may have a higher incidence of TNS or TRI than bupivacaine. Therefore, mepivacaine may be used before bupivacaine in spinal anesthesia.


Assuntos
Raquianestesia , Mepivacaína , Raquianestesia/efeitos adversos , Raquianestesia/métodos , Anestésicos Locais , Bupivacaína/efeitos adversos , Humanos , Mepivacaína/uso terapêutico , Dor , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Ecotoxicol Environ Saf ; 207: 111198, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32905932

RESUMO

Cd pollution in farmland is becoming a serious problem because it affects the safety of rice production and human health. Salicylic acid (SA) plays crucial roles in plant development and mediates plant responses to biotic and abiotic stress. This study assessed the molecular and physiological mechanisms of SA spraying effects on Cd tolerance and Cd accumulation in rice. Spraying of 0.1 mM SA had no great effect on the agronomic traits of rice, but significantly decreased Cd accumulation in rice grains, and SA spraying increased the Cd contents in leaves (only at the mature stage) and decreased the Cd contents in panicles (only at the filling and mature stage), but had no evident impact on the Cd content of other tissues and other growth stages. SA spraying reduced Cd accumulation in rice grains by promoting the deposition and fixation of Cd in the cell wall of leaves, thus preventing Cd being transferred from leaves to rice grains at the filling stage. SA spraying also decreased Cd toxicity by reducing H2O2 and MDA accumulation and increasing the chlorophyll content in rice leaves. Furthermore, SA spraying remarkably decreased Cd accumulation in rice grains by modulating the expression level of the genes associated with Cd translocation and accumulation to control the Cd accumulation in rice. Hence, SA spraying reduced the inhibition of Cd on the plant height caused by Cd and increased the dry weight of shoots in the vegetative growth period of rice seedlings, and it reduced Cd transport from leaves to grains, thus reducing Cd content in rice. These findings provide a novel perspective and a new method for reducing Cd accumulation in rice.


Assuntos
Cádmio/toxicidade , Oryza/metabolismo , Substâncias Protetoras/farmacologia , Ácido Salicílico/farmacologia , Poluentes do Solo/toxicidade , Cádmio/metabolismo , Clorofila/metabolismo , Poluição Ambiental , Humanos , Peróxido de Hidrogênio/metabolismo , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Poluentes do Solo/metabolismo , Estresse Fisiológico/efeitos dos fármacos
12.
Chemosphere ; 263: 128034, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297052

RESUMO

Cadmium (Cd) contamination, which poses a serious threat to human health, has been recognized as a major threat to the agricultural system and crop production. Salicylic acid (SA) is a signaling molecule that plays an important role in against Cd toxicity. Previously, we found that spraying rice with SA could reduce the Cd accumulation in rice grains grown in Cd-contaminated soil. In this study, we studied the specific mechanism of SA spray on reducing Cd accumulation in rice grain. The results showed that treatment with SA could alleviate Cd toxicity in rice by increasing the activities of antioxidant enzymes that reduce hydrogen peroxide (H2O2) accumulation, but not by changing the pH, or total or available Cd of the soil. The key factor by which SA treatment reduced Cd accumulation in rice grains was by decreasing the Cd content in rice leaves at the flowering stage. This indicated that SA could modulate the Cd accumulation in shoots, reducing the Cd translocation to rice grains. Furthermore, SA could increase the H2O2 content, activating the SA-signaling pathway and modulating the expression levels of Cd transporters (OsLCT1 and OsLCD) in rice leaves to increase Cd tolerance and reduce Cd accumulation in the rice grain. Thus, spraying rice with SA may be effective measure to cope with Cd contamination in paddy soils.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Cádmio/toxicidade , Grão Comestível/química , Humanos , Peróxido de Hidrogênio , Ácido Salicílico , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
13.
Exp Ther Med ; 8(4): 1111-1114, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25187806

RESUMO

The present study aimed to identify a new selective glucocorticoid receptor (GR) ligand for the treatment of chronic inflammation in type 2 diabetes mellitus. The IN Cell Analyzer 1000 platform was employed to screen for compounds that may promote GR nuclear translocation. A mammalian two-hybrid system and transactivation assay-were used to analyze the selected GR ligands and evaluate their activities for GR transcription and the recruitment of co-activators. A novel selective GR ligand, compound Q40, was identified that was able to promote GR nuclear translocation in a short period of time. It increased the ability of GR to recruit co-activators in a concentration-dependent manner, but had no positive effect on GR transcriptional activity. In conclusion, an increase in the expression levels of gluconeogeneic genes, induced by the transcriptional activation of GR, is the predisposing factor most commonly associated with the side-effects of glucocorticoids. The results suggest that compound Q40 is a ligand of the GR and exerts an agonistic action on the recruitment of co-activators without sugar dysmetabolism-related side-effects. Thus, compound Q40 has the potential to be used as an anti-inflammatory adjuvant therapy with minimal side-effects in patients with type 2 diabetes mellitus.

14.
Nanoscale Res Lett ; 8(1): 44, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23336623

RESUMO

Biological materials with hierarchically laminated structures usually exhibit a good synergy between strength and fracture toughness. Here, we show that a bio-inspired (polyelectrolyte (PE)/TiO2)4 nanolayered composite with a thickness ratio of TiO2 and amorphous PE layers of about 1.1 has been prepared successfully on Si substrates by layer-by-layer self-assembly and chemical bath deposition methods. Microstructures of the nanolayered composite were investigated by scanning electron microscopy, secondary ion mass spectroscopy, and high-resolution transmission microscopy. Mechanical performance of the composite was characterized by instrumented indentation. The composite consisting of 17.9-nm-thick nanocrystalline TiO2 and 16.4-nm-thick amorphous PE layers has a strength of about 245 MPa, which is close to that of shells, while the fracture toughness of the composite, KIC = 1.62 ± 0.30 MPa · m1/2, is evidently higher than that of the bulk TiO2. A possible strategy to build the composite at nanoscale for high mechanical performance was addressed.

15.
Se Pu ; 20(2): 187-9, 2002 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12541983

RESUMO

A novel method is suggested for the determination of benzo[a]pyrene in mainstream smoke. Extraction of Cambridge pads was cleaned up with methanol/n-heptane extraction system and silica solid-phase extraction (SPE). The eluted solution containing benzo[a]pyrene was evaporated gently to complete dryness with N2 flow, then reconstituted in 200 microL ethyl acetate for determination with gas chromatography-mass spectrometry selected ion monitoring (SIM). The proposed method had good results and precision for the separation of pyrene in complex matrices.


Assuntos
Benzo(a)pireno/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nicotiana , Fumaça/análise , Solventes
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