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1.
Chem Rev ; 123(6): 3007-3088, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36802560

RESUMO

Polymers have been widely applied in various fields in the daily routines and the manufacturing. Despite the awareness of the aggressive and inevitable aging for the polymers, it still remains a challenge to choose an appropriate characterization strategy for evaluating the aging behaviors. The difficulties lie in the fact that the polymer features from the different aging stages require different characterization methods. In this review, we present an overview of the characterization strategies preferable for the initial, accelerated, and late stages during polymer aging. The optimum strategies have been discussed to characterize the generation of radicals, variation of functional groups, substantial chain scission, formation of low-molecular products, and deterioration in the polymers' macro-performances. In view of the advantages and the limitations of these characterization techniques, their utilization in a strategic approach is considered. In addition, we highlight the structure-property relationship for the aged polymers and provide available guidance for lifetime prediction. This review could allow the readers to be knowledgeable of the features for the polymers in the different aging stages and provide access to choose the optimum characterization techniques. We believe that this review will attract the communities dedicated to materials science and chemistry.

2.
Mol Phylogenet Evol ; 197: 108082, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38705251

RESUMO

In addition to topography and climate, biogeographic dispersal has been considered to influence plant diversity in the Himalaya-Hengduan Mountains (HHM), yet, the mode and tempo of sky island dispersal and its influence on species richness has been little explored. Through phylogenetic analysis of Gaultheria ser. Trichophyllae, a sky island alpine clade within the HHM, we test the hypothesis that dispersal has affected current local species richness. We inferred the dynamics of biogeographic dispersal with correlation tests on direction, distance, occurrence time, and regional species richness. We found that G. ser. Trichophyllae originated at the end of the Miocene and mostly dispersed toward higher longitudes (eastward). In particular, shorter intra-regional eastward dispersals and longer inter-regional westward dispersals were most frequently observed. We detected a prevalence of eastward intra-region dispersals in both glacial periods and interglacials. These dispersals may have been facilitated by the reorganization of paleo-drainages and monsoon intensification through time. We suggest that the timing of dispersal corresponding to glacial periods and the prevalence of intra-region dispersal, rather than dispersal frequency, most influenced the pattern of species richness of G. ser. Trichophyllae. This study facilitates a more comprehensive understanding of biodiversity in the sky islands within the HHM.


Assuntos
Biodiversidade , Filogenia , China , Filogeografia , Ilhas , Dispersão Vegetal
3.
Perfusion ; : 2676591231214081, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938147

RESUMO

INTRODUCTION: Acute peripheral and coronary artery embolism are common complications of diabetes mellitus and greatly affect the clinical outcome of patients with diabetes; however, there are few reports about the symptoms and prognosis of patients with acute myocardial infarction (AMI) and concurrent acute lower extremity arterial embolism (ALEAE). CASE PRESENTATION: A 44-year-old man with a history of 4 years of type 1 diabetes was admitted to hospital after suddenly experiencing severe pain in his right lower limb and feeling tightness in the left anterior chest area. Ultrasonography revealed distal occlusion of the right superficial femoral artery, and an electrocardiogram showed acute anterior interstitial myocardial infarction. After conservative treatment for 2 days, the patient had severe necrosis of the lower limbs and secondary injury of multiple organs. Haemodialysis and heparin anticoagulant therapy were performed before amputation. Twelve days after the operation, the patient's condition was stable, and he was transferred out of the intensive care unit. CONCLUSIONS: If patients with ALEAE miss the opportunity for early treatment, even with AMI, emergency amputation under general anaesthesia is the right strategy to save lives.

4.
Molecules ; 28(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38067522

RESUMO

Poly(vinyl chloride) (PVC) is widely used in various fields and requires the use of thermal stabilizers to enhance its thermal stability during processing because of its poor thermal stability. Layered double hydroxides (LDHs) are widely considered to be one kind of highly efficient and environmentally friendly PVC thermal stabilizer. To investigate the thermal stabilizing process of layered double hydroxides (LDHs) in PVC resin, PVC and MgAl-LDHs powders with different interlayer anions (CO32-, Cl-, and NO3-) were physically mixed and aged at 180 °C. The structure of LDHs at different aging times was studied using XRD, SEM, and FT-IR. The results show that the thermal stabilizing process of LDHs on PVC mainly has three stages. In the first stage, the layers of LDHs undergo a reaction with HCl, which is released during the thermal decomposition of PVC. Subsequently, the ion exchange process occurs between Cl- and interlayer CO32-, resulting in the formation of MgAl-Cl-LDHs. Finally, the layers of MgAl-Cl-LDHs react with HCl slowly. During the thermal stabilizing process of MgAl-Cl-LDHs, the peak intensity of XRD reduces slightly, and no new XRD peak emerges. It indicates that only the first step happens for MgAl-Cl-LDHs. The TG-DTA analysis of LDHs indicates that the interaction of LDHs with different interlayer anions has the following order: NO3- < CO32- < Cl-, according to the early coloring in the thermal aging test of PVC composites. The results of the thermal aging tests suggest that LDHs with a weak interaction between interlayer anions and layers can enhance the early stability of PVC significantly. Furthermore, the thermal aging test demonstrates that LDHs with high HCl absorption capacities exhibit superior long-term stabilizing effects on PVC resin. This finding provides a valuable hint for designing an LDHs/PVC resin with a novel structure and excellent thermal stability.

5.
BMC Oral Health ; 23(1): 89, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36782192

RESUMO

BACKGROUND: Dynamic navigation systems have a broad application prospect in digital implanting field. This study aimed to explore and compare the dynamic navigation system learning curve of dentists with different implant surgery experience through dental models. METHODS: The nine participants from the same hospital were divided equally into three groups. Group 1 (G1) and Group 2 (G2) were dentists who had more than 5 years of implant surgery experience. G1 also had more than 3 years of experience with dynamic navigation, while G2 had no experience with dynamic navigation. Group 3 (G3) consisted of dentists with no implant surgery experience and no experience with dynamic navigation. Each participant sequentially placed two implants (31 and 36) on dental models according to four practice courses (1-3, 4-6, 7-9, 10-12 exercises). Each dentist completed 1-3, 4-6 exercises in one day, and then 7-9 and 10-12 exercises 7 ± 1 days later. The preparation time, surgery time and related implant accuracy were analyzed. RESULTS: Three groups placed 216 implants in four practice courses. The regressions for preparation time (F = 10.294, R2 = 0.284), coronal deviation (F = 4.117, R2 = 0.071), apical deviation (F = 13.016, R2 = 0.194) and axial deviation (F = 30.736, R2 = 0.363) were statistically significant in G2. The regressions for preparation time (F = 9.544, R2 = 0.269), surgery time (F = 45.032, R2 = 0.455), apical deviation (F = 4.295, R2 = 0.074) and axial deviation (F = 21.656, R2 = 0.286) were statistically significant in G3. Regarding preparation and surgery time, differences were found between G1 and G3, G2 and G3. Regarding implant accuracy, differences were found in the first two practice courses between G1 and G3. CONCLUSIONS: The operation process of dynamic navigation system is relatively simple and easy to use. The linear regression analysis showed there is a dynamic navigation learning curve for dentists with or without implant experience and the learning curve of surgery time for dentists with implant experience fluctuates. However, dentists with implant experience learn more efficiently and have a shorter learning curve.


Assuntos
Implantes Dentários , Cirurgia Assistida por Computador , Humanos , Curva de Aprendizado , Cirurgia Assistida por Computador/métodos , Implantação Dentária Endóssea/métodos , Projetos de Pesquisa
6.
Anal Chem ; 94(2): 1382-1389, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34985873

RESUMO

Adsorbed oxygen and lattice oxygen are crucial parameters for catalyst characterization and catalytic oxidation mechanism. Therefore, rapid discrimination of adsorbed oxygen and lattice oxygen is highly desired. Herein, a direct correlation between cataluminescence (CTL) kinetic curve and oxygen species was discovered. The adsorbed oxygen-catalyzed CTL only lasted for a few minutes, whereas the lattice oxygen-catalyzed CTL could exhibit hours of continuous luminescence. The long-term CTL was attributed to the slow migration of lattice oxygen in a slow and continuous catalytic oxidation reaction. In addition to the discrimination between the adsorbed oxygen and lattice oxygen by the CTL kinetic processes, the corresponding CTL intensity was positively proportional to their amounts. Accordingly, the developed catalytic oxidation-related CTL can be used as an indicator for rapid discrimination and determination of adsorbed oxygen and lattice oxygen in catalysts. Oxygen species detected by the proposed CTL method not only matched well with those obtained by conventional X-ray photoelectron spectroscopy and O2-temperature programmed methods but also offered some distinguished advantages, such as convenient operation, fast response, and low cost. It can be expected that the established oxygen-responsive CTL probe has great potential in distinguishing adsorbed oxygen and lattice oxygen in various catalysts.

7.
Anal Chem ; 94(11): 4813-4820, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35274939

RESUMO

It remains a great challenge to develop effective strategies for improving the weak cathodic electrogenerated chemiluminescence (ECL) of the luminol-dissolved O2 system. Interface modulation between metal and supports is an attractive strategy to improve oxygen reduction reaction (ORR) activity. Therefore, the design of electrocatalysts via interface modulation would provide new opportunities for the ECL amplification involving reactive oxygen species (ROSs). Herein, we have fabricated an Ag single-atom catalyst with an oxygen-bridged interface (Ag-O-Co) through the electrodeposition of Ag on a CoAl layered double hydroxide (LDH) modified indium tin oxide (ITO) electrode (Ags/LDH/ITO). Interestingly, it was found that the cathodic ECL intensity of the luminol-dissolved O2 system at the Ags/LDH/ITO electrode was extraordinarily enhanced in comparison with those at bare ITO and other Ag nanoparticle-based electrodes. The enhanced ECL performances of the Ags/LDH/ITO electrode were attributed to the increasing amounts of ROSs by electrocatalytic ORR in the Ag-O-Co interface. The electron redistribution of Ag and Co bimetallic sites could accelerate electron transfer, promote the adsorption of O2, and sufficiently activate O2 through a four-electron reaction pathway. Finally, the luminol cathodic ECL intensity was greatly improved. Our findings can provide inspiration for revealing the interface effects between metal and supports, and open up a new avenue to improve the luminol cathodic ECL.


Assuntos
Luminol , Nanopartículas Metálicas , Eletrodos , Luminescência , Medições Luminescentes , Oxigênio , Prata
8.
J Oral Pathol Med ; 51(3): 290-300, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35088463

RESUMO

BACKGROUND: Accumulating evidence shows that pleomorphic adenoma (PA) exhibits a unique capsular invasion and with a crucial role in recurrence. This study was designed to explore RNA expression profiles in salivary gland PA in an attempt to further analyse genes associate with capsule invasion. METHODS: We evaluated the expression profiles of 4 salivary gland PA patients by RNA-sequencing. The principal functions of the differentially expressed mRNAs (DEGs) were explored using GO and KEGG analysis. Then, RT-qPCR and correlation analyses were performed to verify the candidate DEGs in 59 PA patients, and immunohistochemical examinations were conducted to validate candidate DEGs. Finally, the COMP-related genes were screened using correlation and biological pathway enrichment analysis, and further validated by RT-qPCR. RESULTS: A total of 974 DEGs were significantly upregulated, and 1464 were downregulated (fold change ≥2.0; p < 0.05). Based on GO and KEGG analyses, extracellular matrix organization and the PI3K-Akt signalling pathway might play pivotal roles in the tumorigenesis of PA. 40 DEGs were screened and validated by RT-qPCR, 11 upregulated and 5 downregulated DEGs were consistent with the sequencing results. Cartilage oligomeric matrix protein (COMP) was identified to have a significant correlation with the capsular invasion of PA and expression of COMP in patients with invasive capsular PA was significantly stronger than PA. Finally, further results could reveal that 5 highest scoring genes were screened as hub genes for COMP. CONCLUSIONS: These findings suggested that COMP may be a prognostic target for PA and might contribute to its capsular invasion.


Assuntos
Adenoma Pleomorfo , Proteína de Matriz Oligomérica de Cartilagem , Neoplasias das Glândulas Salivares , Adenoma Pleomorfo/patologia , Proteína de Matriz Oligomérica de Cartilagem/genética , Proteína de Matriz Oligomérica de Cartilagem/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares/metabolismo
9.
Nature ; 538(7623): 84-87, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27708303

RESUMO

Lower olefins-generally referring to ethylene, propylene and butylene-are basic carbon-based building blocks that are widely used in the chemical industry, and are traditionally produced through thermal or catalytic cracking of a range of hydrocarbon feedstocks, such as naphtha, gas oil, condensates and light alkanes. With the rapid depletion of the limited petroleum reserves that serve as the source of these hydrocarbons, there is an urgent need for processes that can produce lower olefins from alternative feedstocks. The 'Fischer-Tropsch to olefins' (FTO) process has long offered a way of producing lower olefins directly from syngas-a mixture of hydrogen and carbon monoxide that is readily derived from coal, biomass and natural gas. But the hydrocarbons obtained with the FTO process typically follow the so-called Anderson-Schulz-Flory distribution, which is characterized by a maximum C2-C4 hydrocarbon fraction of about 56.7 per cent and an undesired methane fraction of about 29.2 per cent (refs 1, 10, 11, 12). Here we show that, under mild reaction conditions, cobalt carbide quadrangular nanoprisms catalyse the FTO conversion of syngas with high selectivity for the production of lower olefins (constituting around 60.8 per cent of the carbon products), while generating little methane (about 5.0 per cent), with the ratio of desired unsaturated hydrocarbons to less valuable saturated hydrocarbons amongst the C2-C4 products being as high as 30. Detailed catalyst characterization during the initial reaction stage and theoretical calculations indicate that preferentially exposed {101} and {020} facets play a pivotal role during syngas conversion, in that they favour olefin production and inhibit methane formation, and thereby render cobalt carbide nanoprisms a promising new catalyst system for directly converting syngas into lower olefins.


Assuntos
Alcenos/síntese química , Monóxido de Carbono/química , Carbono/química , Carvão Mineral , Cobalto/química , Hidrogênio/química , Nanoestruturas/química , Gás Natural , Biomassa , Catálise , Metano/síntese química , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , Pressão
10.
Oral Dis ; 28(7): 1831-1845, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34145926

RESUMO

OBJECTIVE: The treatment of patients with primary Sjögren's syndrome is a clinical challenge. Gene expression profile analysis and comprehensive network methods for complex diseases can provide insight into molecular characteristics in the clinical context. MATERIALS AND METHODS: We downloaded gene expression datasets from the Gene Expression Omnibus (GEO) database. We screened differentially expressed genes (DEG) between the pSS patients and the controls by the robust rank aggregation (RRA) method. We explored DEGs' potential function using gene function annotation and PPI network analysis. RESULTS: GSE23117, GSE40611, GSE80805, and GSE127952 were included, including 38 patients and 30 controls. The RRA integrated analysis determined 294 significant DEGs (241 upregulated and 53 downregulated), and the most significant gene aberrantly expressed in SS was CXCL9 (p = 6.39E-15), followed by CXCL13 (p = 1.53E-13). Immune response (GO:0006955; p = 4.29E-32) was the most significantly enriched biological process in GO (gene ontology) analysis. KEGG pathway enrichment analysis showed that cytokine-cytokine receptor interaction (hsa04060; p = 6.46E-10) and chemokine signaling pathway (hsa04062; p = 9.54E-09) were significantly enriched. We defined PTPRC, CD86, and LCP2 as the hub genes based on the PPI results. CONCLUSION: Our integrated analysis identified gene signatures and helped understand molecular changes in pSS.


Assuntos
Síndrome de Sjogren , Transcriptoma , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Humanos , Mapas de Interação de Proteínas/genética , Síndrome de Sjogren/genética
11.
J Clin Nurs ; 31(21-22): 3021-3031, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35060252

RESUMO

AIMS AND OBJECTIVES: To systematically appraise the effects of eHealth cognitive behavioural therapy on depression and anxiety severity, quality of life, adherence and attrition rates observed in adults with clinically diagnosed depression. BACKGROUND: eHealth-based cognitive behavioural therapy is an increasingly popular intervention on depression, but current reviews investigating the effects of eHealth interventions on depression are not exclusive to the clinically depressed. DESIGN: A systematic review and meta-analysis. METHODS: Following the PRISMA guidelines, a systematic search of randomised controlled trials related to eHealth cognitive behavioural therapy published from inception from six databases and three trial registries was undertaken. RESULTS: A total of 15 studies were included in this systematic review. The meta-analysis revealed that, when compared to passive comparators, eHealth cognitive behavioural therapy had a statistically significant effect on depression (d = -0.62, 95% CI: -0.96 to -0.28, p = .0003) and anxiety severity (d = -0.65, 95% CI: -1.10 to -0.21, p = .004) but not for quality of life (d = 0.30, 95% CI: -0.09 to 0.07, p = .13). When compared to active comparators, a statistically significant effect on depression (d = -0.31, 95% CI: -0.55 to -0.07, p = .01) and anxiety severity (d = -0.50, 95% CI: -0.81 to -0.19, p = .002) was observed, but not for quality of life (d = 0.22, 95% CI: -0.04 to 0.48, p = .10). Weighted averages for adherence and attrition rates were low. CONCLUSION: eHealth cognitive behavioural therapy showed effectiveness in reducing depression and anxiety severity, but not quality of life. Further research is required to culturally adapt CBT interventions and explore the long-term benefits of eHealth cognitive behavioural therapy. RELEVANCE TO CLINICAL PRACTICE: The use of eHealth-based cognitive behavioural therapy could potentially bridge treatment gaps and serve as an adjunct to active treatment plans or an alternative for those without access to treatment.


Assuntos
Terapia Cognitivo-Comportamental , Telemedicina , Adulto , Ansiedade/terapia , Transtornos de Ansiedade/terapia , Depressão/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
BMC Oral Health ; 22(1): 139, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473637

RESUMO

INTRODUCTION: The aim of this study was to verify whether the use of short implants could optimize stress distribution of bone surrounding implants in atrophic mandibles with different bone qualities. METHODS: A three-dimensional model of the atrophic mandible with three levels of bone quality was made using computer software. Short implants (6 mm) and standard implants (10 mm) were used in four designs: Design 1 "All-On four", Design 2 "All-On-four" with two short implants, Design 3 four vertical implants with two short implants, and Design 4 six short implants. The distal short implants were placed at the first molar position. All twelve models were imported into finite element analysis software, and 110 N oblique force was loaded on the left second premolar. Maximum principal stress values of peri-implant bone and the volumes of bone with over 3000 microstrians (overload)were analyzed. RESULT: Stress values and volumes of overload bone increased in all four groups with the decline of bone quality. The highest stress values were found in the cortical bone surrounding the Design 1 inclined implant in two lower bone quality mandibles, and the lowest in Design 3. However, Design 1 had less overload bone tissue than all three designs with short implants. CONCLUSION: Short implants placed posteriorly helped decrease stress values in peri-implant bone, while bone surrounding short implants had a high resorption risk in low bone quality mandible.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Análise do Estresse Dentário/métodos , Análise de Elementos Finitos , Humanos , Mandíbula/cirurgia
13.
BMC Oral Health ; 22(1): 62, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260122

RESUMO

BACKGROUND: The application of calcium phosphate (CaP)-based bone substitutes plays an important role in periodontal regeneration, implant dentistry and alveolar bone reconstruction. The incorporation of strontium (Sr) into CaP-based bone substitutes appears to improve their biological properties, but the reported in vivo bone repair performance is inconsistent among studies. Herein, we conducted a systematic review and meta-analysis to investigate the in vivo performance of Sr-doped materials. METHODS: We searched PubMed, EMBASE (via OVIDSP), and reference lists to identify relevant animal studies. The search, study selection, and data extraction were performed independently by two investigators. Meta-analyses and sub-group analyses were conducted using Revman version 5.4.1. The heterogeneity between studies were assessed by I2. Publication bias was investigated through a funnel plot. RESULTS: Thirty-five studies were finally enrolled, of which 16 articles that reported on new bone formation (NBF) were included in the meta-analysis, covering 31 comparisons and 445 defects. The overall effect for NBF was 2.25 (95% CI 1.61-2.90, p < 0.00001, I2 = 80%). Eight comparisons from 6 studies reported the outcomes of bone volume/tissue volume (BV/TV), with an overall effect of 1.42 (95% CI 0.65-2.18, p = 0.0003, I2 = 75%). Fourteen comparisons reported on the material remaining (RM), with the overall effect being -2.26 (95% CI - 4.02 to - 0.50, p = 0.0009, I2 = 86%). CONCLUSIONS: Our study revealed that Sr-doped calcium phosphate bone substitutes improved in vivo performance of bone repair. However, more studies are also recommended to further verify this conclusion.


Assuntos
Substitutos Ósseos , Fosfatos de Cálcio , Animais , Substitutos Ósseos/uso terapêutico , Osso e Ossos , Fosfatos de Cálcio/uso terapêutico , Humanos , Estrôncio/uso terapêutico
14.
Anal Chem ; 93(4): 2678-2686, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33459017

RESUMO

As an attractive electrochemiluminescence (ECL) emitter, graphitic carbon nitride (CN) still suffers from weak and unstable ECL signals for its poor conductivity and the occurrence of electrode passivation. In this study, a simple nitrogen vacancy (NV) engineering strategy has been developed for the improvement of ECL performances (intensity and stability) for the first time. In comparison to pristine CN (RSD = 51.98% for 10 continuous scan), ca. 60 times amplification in ECL intensity and 70 times enhancement in ECL efficiency for CN modified with NVs (CN-NVs) were obtained. In addition, more stable ECL emissions (RSD = 0.53%) were achieved for CN-NV-550 by thermal treatment of pristine CN in a N2 atmosphere for another 2 h at 550 °C. The mechanism study for the vital role of NVs on the ECL of CN-NVs revealed that NVs can not only facilitate electron transfer to amplify the ECL intensity but also serve as the electron trap to inhibit electrode passivation. More interestingly, a series of CN-NVs exhibited a tunable ECL wavelength range from 470 to 516 nm with different NV contents. Moreover, their ECL spectra showed an obvious red-shift of the wavelength with their corresponding fluorescence spectra. These findings confirmed that the ECL emissions of CN-NVs were susceptible to the relevant surface states of NVs. Our work may open up a promising pathway for improving ECL performances of CN and create new possibilities for multitarget simultaneous detection based on ECL and construction of color tunable light-emitting devices.

15.
Anal Chem ; 93(32): 11291-11297, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34346688

RESUMO

Au nanoparticle-amplified electrochemiluminescence (ECL) signals are generally realized by nanoparticle morphology modification, functionalization, and nanoalloys formation. It remains a great challenge to utilize the intrinsic catalytic activity of spherical Au nanoparticles for ECL performance improvement. In this work, we prepared the oxygen vacancy-rich CoAl-layered double hydroxide (LDH-Ov)-supported spherical Au nanoparticles via alkali etching of LDH and electrodeposition of Au nanoparticles on the surface of LDH. It was found that the luminol ECL signals of the as-prepared system were significantly enhanced by forming the strong electronic metal-support interaction (EMSI) between Au nanoparticles and LDH-Ov. The further mechanism study demonstrated that EMSI can increase the electron density of interfacial Au atom (Auδ-) due to a redistribution of charge and promote electron transfer between Au species and LDH-Ov. This study not only introduces EMSI to the ECL field but also paves a new way to the applications of the intrinsic activity of spherical Au nanoparticles in ECL signal amplification. We anticipate that EMSI would be applied to other metal nanocatalysts for the development of highly efficient ECL systems.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Técnicas Eletroquímicas , Eletrônica , Ouro , Limite de Detecção , Medições Luminescentes
16.
Anal Chem ; 92(11): 7794-7799, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32380823

RESUMO

Interparticle distance (ID) is generally used for spatial evaluation on the dispersion of nanofillers in polymer nanocomposites (PNCs) in order to gain in-depth insight into fundamental understanding of reinforcement and structure-property correlation. However, currently available methods mainly rely on two-dimensional observation technologies or simulation methods. Herein, using layered double hydroxides (LDHs) in low-density polyethylene (LDPE) as a model matrix, we developed a novel spatial ID determination method through a post labeling fluorescent imaging technique. The spatial ID of LDH nanofillers was achieved by a MATLAB program based on the 3D coordinates of LDH nanofillers in PNCs. The spatial ID data indicated the varied dispersion states of LDH nanofillers from "random", "even", to "clustered" in PNCs. More importantly, the so-called exceptional performances of PNCs at high loading of LDH nanofillers can be reasonably explained in combination with the mechanical studies. This proposed approach could undoubtedly provide valuable information in elucidating the structure-property correlation in PNCs. We believe that this work would be a guide to design advanced PNC materials.

17.
Analyst ; 145(15): 5068-5089, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32608421

RESUMO

HClO/ClO- is the most effective antibacterial active oxygen in neutrophils. However, its excessive existence often leads to the destruction of human physiological mechanisms. In recent years, the developed luminescent probes for the detection of HClO/ClO- are not only conducive to improve the sensitivity and selectivity of HClO/ClO- detection, but also play a crucial role in understanding the biological functions of HClO/ClO-. In addition, luminescent probe-based biological imaging for HClO/ClO- at sub-cellular resolution has become a powerful tool for biopathology and medical diagnostic research. This article reviews a variety of luminescent probes for the detection of HClO/ClO-in vitro and in vivo with different design principles and mechanisms, including fluorescence, phosphorescence, and chemiluminescence. The photophysical/chemical properties and biological applications of these luminescent probes were outlined. Finally, we summarized the merits and demerits of the developed luminescent probes and discussed their challenges and future development trends. It is hoped that this review can provide some inspiration for the development of luminescent probe-based strategies and to promote the further research of biomedical luminescent probes for HClO/ClO-.


Assuntos
Ácido Hipocloroso , Luminescência , Corantes Fluorescentes , Humanos , Microscopia de Fluorescência
18.
Knee Surg Sports Traumatol Arthrosc ; 28(7): 2334-2342, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31781802

RESUMO

PURPOSE: Adductor canal block (ACB) provides postoperative pain relief as effectively as femoral nerve block (FNB) does, and it preserves the strength of the quadriceps femoris. However, its effect on rehabilitation after arthroscopic partial meniscectomy has not been reported. The purpose of this study was to determine the effect of pre-operative ACB and FNB on the quality of rehabilitation after arthroscopic partial meniscectomy. METHODS: A total of 150 patients undergoing arthroscopic partial meniscectomy were randomly allocated to the FNB group (receiving 0.3% ropivacaine 30 ml at the thighroot-femoral nerve), the ACB group (receiving 0.3% ropivacaine 30 ml at mid-thigh adductor canal), or the control group. The primary outcome was the Hospital for Special Surgery (HSS) knee score on the 30th postoperative day. RESULTS: The HSS knee score of the ACB group on the 30th day after the operation was significantly higher than those of the FNB and control groups (88.6 ± 5.3 vs. 85.3 ± 6.9 and 81.2 ± 5.9, respectively; P < 0.05). Both the ACB and FNB groups showed excellent rehabilitation, indicating similar rehabilitation quality for both treatments. CONCLUSION: ACB is similar to FNB concerning the quality of rehabilitation and pain relief after arthroscopic partial meniscectomy, while ACB has little effect on the strength of the quadriceps femoris. LEVEL OF EVIDENCE: I TRIAL REGISTRATAION: This trial was registered in the Chinese Clinical Trial Registry (ChiCTR-INC-16008346).


Assuntos
Artroplastia do Joelho/reabilitação , Artroscopia , Nervo Femoral/efeitos dos fármacos , Meniscectomia , Bloqueio Nervoso/métodos , Músculo Quadríceps/fisiologia , Coxa da Perna , Adulto , Fáscia , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Manejo da Dor , Dor Pós-Operatória , Período Pós-Operatório , Ropivacaina
19.
Anal Chem ; 91(7): 4513-4519, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30862158

RESUMO

The rapid and effective recognition techniques for crystal facets in noble metal nanocrystals (NCs) are highly desirable in evaluation of their catalytic performances. Herein, it was found that the variation trend of cataluminescence (CTL) intensity in the presence of propanol was proportional to the crystal facets index change of LDH-supported Pd@Au NCs. The mechanism investigation for the propanol-triggered CTL on the surface of layered double hydroxide (LDH)-supported Pd@Au NCs revealed that the abundant negative charge in the high-index facets of LDH-supported Pd@Au NCs facilitated electron transfer between NCs and volatile propanol, resulting in acceleration of the CTL reactions. Accordingly, the propanol-triggered CTL can be as an indicator for rapid screening of crystal facets in NCs. Its universality had further been verified by screening crystal facets in LDH-supported Pd NCs. The crystal facets detected by propanol CTL probe were well-matched with those obtained by conventional high-resolution transmission electron microscope. The proposed CTL strategy exhibits some advantages, such as convenient operation, rapid response, long-term stability, and low cost. And it is expected crystal facets of other kinds of NCs could be screened by replaceable CTL probe.

20.
Cochrane Database Syst Rev ; 10: CD012959, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31618443

RESUMO

BACKGROUND: Severe acute pancreatitis is associated with high rates of mortality and life-threatening complications. Continuous veno-venous hemofiltration (CVVH) has been used in some centers to reduce mortality and avoid local or systemic complications, however its efficiency and safety is uncertain. OBJECTIVES: To assess the benefits and harms of CVVH in patients suffering from severe acute pancreatitis; to compare the effects of different CVVH techniques; and to evaluate the optimal time for delivery of CVVH. SEARCH METHODS: We searched the Cochrane Library (2019, Issue 8), MEDLINE (1946 to 13 September 2019), Embase (1974 to 13 September 2019), and Science Citation Index Expanded (1982 to 13 September 2019). SELECTION CRITERIA: We included all randomized controlled trials (RCTs) that compared CVVH versus no CVVH in participants with severe acute pancreatitis. We also included RCTs that compared different types of CVVH and different schedules for CVVH in participants with severe acute pancreatitis. DATA COLLECTION AND ANALYSIS: Two review authors independently identified the trials for inclusion, collected the data, and assessed the risk of bias. We performed the meta-analyses using Review Manager 5. We calculated the risk ratio (RR) for dichotomous outcomes, and the mean difference (MD) for continuous outcomes, with 95% confidence intervals (CIs). MAIN RESULTS: We included two studies, involving a total of 94 participants, in the review.Continuous veno-venous hemofiltration versus no interventionWe included one study in which 64 participants with severe acute pancreatitis were randomized to undergo CVVH (32 participants) or no intervention (32 participants). There were no deaths in either group (very low-quality evidence). Adverse events, length of stay in the intensive care unit (ICU), length of hospital stay, total hospital cost, and quality of life were not reported in the study.One type of continuous veno-venous hemofiltration versus a different type of continuous veno-venous hemofiltrationWe included one study in which 30 participants with severe acute pancreatitis were randomized to undergo high-volume CVVH (15 participants) or standard CVVH (15 participants). High-volume CVVH may lead to little or no difference in in-hospital mortality rates (20.0% in the high-volume CVVH group versus 33.3% in the standard CVVH group; risk ratio (RR) 0.60, 95% confidence interval (CI) 0.17 to 2.07; 30 participants; 1 study; low-quality evidence). We are uncertain whether high-volume hemofiltration reduces rates of adverse events (13.3% in both groups; RR 1.00, 95% CI 0.16 to 6.20; 30 participants; 1 study; very low-quality evidence). Length of ICU stay, length of hospital stay, total hospital cost, and quality of life were not reported in the study. AUTHORS' CONCLUSIONS: The quality of the current evidence is very low or low. For both comparisons addressed in this review, data are sparse. It is unclear whether CVVH has any effect on mortality or complications in patients with severe acute pancreatitis. It is also unclear whether high-volume CVVH is superior, equivalent or inferior to standard CVVH in patients with severe acute pancreatitis.

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