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1.
Nature ; 621(7979): 521-529, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37730866

RESUMO

Wildfires are thought to be increasing in severity and frequency as a result of climate change1-5. Air pollution from landscape fires can negatively affect human health4-6, but human exposure to landscape fire-sourced (LFS) air pollution has not been well characterized at the global scale7-23. Here, we estimate global daily LFS outdoor fine particulate matter (PM2.5) and surface ozone concentrations at 0.25° × 0.25° resolution during the period 2000-2019 with the help of machine learning and chemical transport models. We found that overall population-weighted average LFS PM2.5 and ozone concentrations were 2.5 µg m-3 (6.1% of all-source PM2.5) and 3.2 µg m-3 (3.6% of all-source ozone), respectively, in 2010-2019, with a slight increase for PM2.5, but not for ozone, compared with 2000-2009. Central Africa, Southeast Asia, South America and Siberia experienced the highest LFS PM2.5 and ozone concentrations. The concentrations of LFS PM2.5 and ozone were about four times higher in low-income countries than in high-income countries. During the period 2010-2019, 2.18 billion people were exposed to at least 1 day of substantial LFS air pollution per year, with each person in the world having, on average, 9.9 days of exposure per year. These two metrics increased by 6.8% and 2.1%, respectively, compared with 2000-2009. Overall, we find that the global population is increasingly exposed to LFS air pollution, with socioeconomic disparities.


Assuntos
Poluição do Ar , Incêndios , Ozônio , Material Particulado , Humanos , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Incêndios/estatística & dados numéricos , Ozônio/análise , Ozônio/provisão & distribuição , Material Particulado/análise , Material Particulado/provisão & distribuição , Incêndios Florestais/estatística & dados numéricos , Disparidades Socioeconômicas em Saúde
2.
Nano Lett ; 24(5): 1620-1628, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38277130

RESUMO

Neuromorphic devices have attracted significant attention as potential building blocks for the next generation of computing technologies owing to their ability to emulate the functionalities of biological nervous systems. The essential components in artificial neural networks such as synapses and neurons are predominantly implemented by dedicated devices with specific functionalities. In this work, we present a gate-controlled transition of neuromorphic functions between artificial neurons and synapses in monolayer graphene transistors that can be employed as memtransistors or synaptic transistors as required. By harnessing the reliability of reversible electrochemical reactions between carbon atoms and hydrogen ions, we can effectively manipulate the electric conductivity of graphene transistors, resulting in a high on/off resistance ratio, a well-defined set/reset voltage, and a prolonged retention time. Overall, the on-demand switching of neuromorphic functions in a single graphene transistor provides a promising opportunity for developing adaptive neural networks for the upcoming era of artificial intelligence and machine learning.

3.
PLoS Med ; 21(1): e1004341, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38252630

RESUMO

BACKGROUND: More intense tropical cyclones (TCs) are expected in the future under a warming climate scenario, but little is known about their mortality effect pattern across countries and over decades. We aim to evaluate the TC-specific mortality risks, periods of concern (POC) and characterize the spatiotemporal pattern and exposure-response (ER) relationships on a multicountry scale. METHODS AND FINDINGS: Daily all-cause, cardiovascular, and respiratory mortality among the general population were collected from 494 locations in 18 countries or territories during 1980 to 2019. Daily TC exposures were defined when the maximum sustained windspeed associated with a TC was ≥34 knots using a parametric wind field model at a 0.5° × 0.5° resolution. We first estimated the TC-specific mortality risks and POC using an advanced flexible statistical framework of mixed Poisson model, accounting for the population changes, natural variation, seasonal and day of the week effects. Then, a mixed meta-regression model was used to pool the TC-specific mortality risks to estimate the overall and country-specific ER relationships of TC characteristics (windspeed, rainfall, and year) with mortality. Overall, 47.7 million all-cause, 15.5 million cardiovascular, and 4.9 million respiratory deaths and 382 TCs were included in our analyses. An overall average POC of around 20 days was observed for TC-related all-cause and cardiopulmonary mortality, with relatively longer POC for the United States of America, Brazil, and Taiwan (>30 days). The TC-specific relative risks (RR) varied substantially, ranging from 1.04 to 1.42, 1.07 to 1.77, and 1.12 to 1.92 among the top 100 TCs with highest RRs for all-cause, cardiovascular, and respiratory mortality, respectively. At country level, relatively higher TC-related mortality risks were observed in Guatemala, Brazil, and New Zealand for all-cause, cardiovascular, and respiratory mortality, respectively. We found an overall monotonically increasing and approximately linear ER curve of TC-related maximum sustained windspeed and cumulative rainfall with mortality, with heterogeneous patterns across countries and regions. The TC-related mortality risks were generally decreasing from 1980 to 2019, especially for the Philippines, Taiwan, and the USA, whereas potentially increasing trends in TC-related all-cause and cardiovascular mortality risks were observed for Japan. CONCLUSIONS: The TC mortality risks and POC varied greatly across TC events, locations, and countries. To minimize the TC-related health burdens, targeted strategies are particularly needed for different countries and regions, integrating epidemiological evidence on region-specific POC and ER curves that consider across-TC variability.


Assuntos
Tempestades Ciclônicas , Doenças Respiratórias , Humanos , Estados Unidos , Clima , Brasil , Japão
4.
Anal Bioanal Chem ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647693

RESUMO

A highly efficient ratiometric electrochemiluminescence (ECL) immunoassay was explored by bidirectionally regulating the ECL intensity of two luminophors. The immunoassay was conducted in a split-type mode consisting of an ECL detection procedure and a sandwich immunoreaction. The ECL detection was executed using a dual-disk glassy carbon electrode modified with two potential-resolved luminophors (g-C3N4-Ag and Ru-MOF-Ag nanocomposites), and the sandwich immunoreaction using glucose oxidase (GOx)-modified SiO2 nanospheres as labels was carried out in a 96-well plate. The Ag nanoparticles (NPs) acted as bifunctional units both for triggering the resonance energy transfer (RET) with g-C3N4 and for accelerating the electron transfer rate of the Ru-MOF-Ag ECL reaction. When the H2O2 catalyzed by GOx in the 96-well plate was transferred to the dual-disk glass carbon electrode, the doped Ag NPs in the two luminophors could be etched, thus destroying the RET between C3N4 and the accelerated reaction to Ru-MOF, resulting in an opposite trend in the ECL signal outputted from the dual disks. Using the ratio of the two signals for quantification, the constructed immunosensor for a model target, i.e. myoglobin, exhibited a low detection limit of 4.7 × 10-14 g/mL. The ingenious combination of ECL ratiometry, bifunctional Ag NPs, and a split-type strategy effectively reduces environmental and human errors, offering a more precise and sensitive analysis for complex samples.

5.
J Chem Phys ; 160(13)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38557844

RESUMO

The moisture with salt ions adsorbed on the mineral soil surface is crucial to the cohesion process when the media is exposed to marine or coastal environments. However, the impact of salinity on the cohesion of soils is not well studied at the nanoscale. In this study, the salinity effect was investigated by studying the wettability and capillary force of NaCl solutions on quartz substrates via a molecular dynamics-based approach. Besides, a new visualization method was proposed to measure the contact angle of liquid droplets from the aspect of nanoscale. The results indicated that salt ions can weaken the wettability of the liquid on the quartz surface and inhibit the capillary force. Compared with water, the liquid with a 10% NaCl solution can achieve a capillary force reduction of around 70%, resulting in a detrimental effect on the cohesion of soils. Overall, this study enhanced the understanding of the nanoscale salinity effect on the cohesion process and provided insights into the modification of the mechanical properties of soils from the aspect of nanoscale.

6.
BMC Public Health ; 24(1): 1289, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734652

RESUMO

BACKGROUND: Under a changing climate, the joint effects of temperature and relative humidity on tuberculosis (TB) are poorly understood. To address this research gap, we conducted a time-series study to explore the joint effects of temperature and relative humidity on TB incidence in China, considering potential modifiers. METHODS: Weekly data on TB cases and meteorological factors in 22 cities across mainland China between 2011 and 2020 were collected. The proxy indicator for the combined exposure levels of temperature and relative humidity, Humidex, was calculated. First, a quasi-Poisson regression with the distributed lag non-linear model (DLNM) was constructed to examine the city-specific associations between humidex and TB incidence. Second, a multivariate meta-regression model was used to pool the city-specific effect estimates, and to explore the potential effect modifiers. RESULTS: A total of 849,676 TB cases occurred in the 22 cities between 2011 and 2020. Overall, a conspicuous J-shaped relationship between humidex and TB incidence was discerned. Specifically, a decrease in humidex was positively correlated with an increased risk of TB incidence, with a maximum relative risk (RR) of 1.40 (95% CI: 1.11-1.76). The elevated RR of TB incidence associated with low humidex (5th humidex) appeared on week 3 and could persist until week 13, with a peak at approximately week 5 (RR: 1.03, 95% CI: 1.01-1.05). The effects of low humidex on TB incidence vary by Natural Growth Rate (NGR) levels. CONCLUSION: A J-shaped exposure-response association existed between humidex and TB incidence in China. Humidex may act as a better predictor to forecast TB incidence compared to temperature and relative humidity alone, especially in regions with higher NGRs.


Assuntos
Umidade , Tuberculose , China/epidemiologia , Humanos , Tuberculose/epidemiologia , Incidência , Temperatura , Cidades/epidemiologia , Mudança Climática
7.
Angew Chem Int Ed Engl ; 63(30): e202406452, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38735843

RESUMO

Acidic H2O2 synthesis through electrocatalytic 2e- oxygen reduction presents a sustainable alternative to the energy-intensive anthraquinone oxidation technology. Nevertheless, acidic H2O2 electrosynthesis suffers from low H2O2 Faradaic efficiencies primarily due to the competing reactions of 4e- oxygen reduction to H2O and hydrogen evolution in environments with high H+ concentrations. Here, we demonstrate the significant effect of alkali metal cations, acting as competing ions with H+, in promoting acidic H2O2 electrosynthesis at industrial-level currents, resulting in an effective current densities of 50-421 mA cm-2 with 84-100 % Faradaic efficiency and a production rate of 856-7842 µmol cm-2 h-1 that far exceeds the performance observed in pure acidic electrolytes or low-current electrolysis. Finite-element simulations indicate that high interfacial pH near the electrode surface formed at high currents is crucial for activating the promotional effect of K+. In situ attenuated total reflection Fourier transform infrared spectroscopy and ab initio molecular dynamics simulations reveal the central role of alkali metal cations in stabilizing the key *OOH intermediate to suppress 4e- oxygen reduction through interacting with coordinated H2O.

8.
Trends Analyt Chem ; 161: 117000, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36937152

RESUMO

The continuing evolution of the SARS-CoV-2 virus has led to the emergence of many variants, including variants of concern (VOCs). CRISPR-Cas systems have been used to develop techniques for the detection of variants. These techniques have focused on the detection of variant-specific mutations in the spike protein gene of SARS-CoV-2. These sequences mostly carry single-nucleotide mutations and are difficult to differentiate using a single CRISPR-based assay. Here we discuss the specificity of the Cas9, Cas12, and Cas13 systems, important considerations of mutation sites, design of guide RNA, and recent progress in CRISPR-based assays for SARS-CoV-2 variants. Strategies for discriminating single-nucleotide mutations include optimizing the position of mismatches, modifying nucleotides in the guide RNA, and using two guide RNAs to recognize the specific mutation sequence and a conservative sequence. Further research is needed to confront challenges in the detection and differentiation of variants and sublineages of SARS-CoV-2 in clinical diagnostic and point-of-care applications.

9.
Trends Analyt Chem ; 165: 117107, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37317683

RESUMO

Molecular detection of SARS-CoV-2 in gargle and saliva complements the standard analysis of nasopharyngeal swabs (NPS) specimens. Although gargle and saliva specimens can be readily obtained non-invasively, appropriate collection and processing of gargle and saliva specimens are critical to the accuracy and sensitivity of the overall analytical method. This review highlights challenges and recent advances in the treatment of gargle and saliva samples for subsequent analysis using reverse transcription polymerase chain reaction (RT-PCR) and isothermal amplification techniques. Important considerations include appropriate collection of gargle and saliva samples, on-site inactivation of viruses in the sample, preservation of viral RNA, extraction and concentration of viral RNA, removal of substances that inhibit nucleic acid amplification reactions, and the compatibility of sample treatment protocols with the subsequent nucleic acid amplification and detection techniques. The principles and approaches discussed in this review are applicable to molecular detection of other microbial pathogens.

10.
Neurol Sci ; 44(3): 905-912, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36434476

RESUMO

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder characterized by resting tremor, bradykinesia, muscle rigidity, and abnormal gait. The low-density lipoprotein receptor-related protein 10 (LRP10) was recently shown to be a causal gene for PD, and different ethnic cohorts have distinct frequencies and spectrum of LRP10 variants. METHODS: We sequenced the full coding regions and exon-intron boundaries of LRP10 in 129 patients with sporadic Chinese PD to further investigate the connection of LRP10 with PD in a sample of Chinese patients. RESULTS: In this study, we identified four potentially pathogenic mutations, including one novel mutation of p.Gly328Asp and three known mutations of p.Cys165Tyr, p.Arg230Trp, and p.Arg661His in four of the 129 Chinese patients with PD. CONCLUSION: According to our study, the LRP10 gene may attribute to PD pathogenesis.


Assuntos
Proteínas Relacionadas a Receptor de LDL , Doença de Parkinson , Humanos , População do Leste Asiático , Éxons , Íntrons , Proteínas Relacionadas a Receptor de LDL/genética , Mutação , Doença de Parkinson/genética
11.
J Sep Sci ; 46(3): e2200631, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427354

RESUMO

A new multifactor analysis assessment strategy was developed for evaluating, optimizing, and comparing analytical techniques for acrylamide in frying oils. Based on five indices (absolute recovery, absolute matrix effect, the intensity of the full ion scan, and the precursor ion scan to m/z 184 and m/z 241), the proposed strategy was performed with radar analysis, relative contribution analysis, and the entropy-weighted technique for order performance by similarity to ideal solution analysis. Two novel methods based on quick, easy, cheap, effective, rugged, and safe extraction methodology and gel permeation chromatography-liquid-liquid extraction followed by liquid chromatography-tandem mass spectrometry have been developed for the analysis of acrylamide in frying oils. Two methods were suitable for rapid and sensitive analysis of acrylamide in oils in different laboratories, with a limit of quantitation at 2 µg/kg, and the average recovery ranging from 92.5% to 107.8%, with relative standard deviations below 10%. When considering automation efficiency and matrix effects, gel permeation chromatography is the most efficient method, whereas the other method has an advantage when analyzing large samples. The developed methods were used in a pilot study to analyze frying oils with acrylamide content below 9.82 µg/kg, showing that the repeated frying process did not produce significant content of acrylamide in oils.


Assuntos
Acrilamida , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Acrilamida/análise , Projetos Piloto , Cromatografia Líquida/métodos , Óleos , Cromatografia Líquida de Alta Pressão/métodos
12.
Lasers Med Sci ; 38(1): 39, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633696

RESUMO

Alzheimer's disease (AD) and dementia are the most worrying health problems faced by people globally today. Although the pathological features of AD consisting of amyloid-beta (Aß) plaques in the extracellular space (ECS) and intracellular tau tangles are well established, the developed medicines targeting these two proteins have not obtained the expected clinical effects. Photobiomodulation (PBM) describes the therapeutic use of red light (RL) or near-infrared light (NIR) to serve as a noninvasive neuroprotective strategy for brain diseases. The present review discusses the mechanisms of the photoelectric coupling effect (light energy-induced special electronic transition-related alterations in protein structure) of PBM on reducing Aß toxicity. On the one hand, RL or NIR can directly disassemble Aß in vitro and in vivo. On the other hand, formaldehyde (FA)-inhibited catalase (CAT) and H2O2-inactived formaldehyde dehydrogenase (FDH) are formed a vicious circle in AD; however, light energy not only activates FDH to degrade excessive FA (which crosslinks Aß monomer to form Aß oligomers and senile plaques) but also sensitizes CAT to reduce hydrogen peroxide levels (H2O2, which can facilitate Aß aggregation and enhance FA generation). In addition, it also activates mitochondrial cytochrome-c to produce ATP in the neurons. Clinical trials of phototherapeutics or oral coenzyme Q10 have shown positive effects in AD patients. Hence, a promising strategy combined PBM with nanopacked Q10 has been proposed to apply for treating AD.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/radioterapia , Doença de Alzheimer/tratamento farmacológico , Peróxido de Hidrogênio , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/uso terapêutico , Catalase , Luz
13.
Sensors (Basel) ; 23(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37447833

RESUMO

To adapt to the "fine" and "extensive" management characteristics of railway signal equipment operation and maintenance, achieving real-time and interactive monitoring of signal equipment operation status, and developing an integrated approach to equipment operation and maintenance, this paper takes a comprehensive management perspective. To create a lightweight BIM model, the Garland folding algorithm is utilized to simplify the IFC file format. Building on this approach, the data are divided based on building component division standards to obtain separate files containing geometric information and semantic attributes. The geometric information files are converted to a 3D Tiles format, combining BIM semantic attributes with semantic attribute files through an intermediate format. Dynamic data management is achieved by setting the octree space index structure in combination with a view-frustum culling algorithm. Then, the 3D Tiles target file is imported into the Cesium platform, and Node.js is used to achieve three-dimensional visualization of railway signal operation and maintenance. The proposed method is verified using an inbound signal as an example to assess its feasibility. The results demonstrate the potential of the proposed method to achieve stable integration between BIM equipment full lifecycle maintenance and GIS geographical space display. Railway signal equipment is endowed with comprehensive one-click information query functions for equipment positioning and spatial analysis, improving the efficiency and scientific decision-making level of equipment operation and maintenance.


Assuntos
Algoritmos , Sistemas de Informação Geográfica , Análise Espacial
14.
Inflammopharmacology ; 31(2): 887-897, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36642757

RESUMO

OBJECTIVE: Adalimumab (ADM), a humanized antibody against tumour necrosis factor (TNF), is widely applied in treating inflammatory and autoimmune diseases, but its usage in spinal cord injury (SCI) is rarely reported. Hence, this study aimed to explore the effect of ADM with or without erythropoietin (EPO) on microglial polarization, neuroinflammation, neural apoptosis, and functional recovery in SCI. METHODS: Primary microglia were stimulated with lipopolysaccharide (LPS) and then treated with ADM, EPO, or ADM combined with EPO. Then, primary neurons were incubated in the microglial culture medium. SCI rats were established and then treated with ADM, EPO or ADM combined with EPO. RESULTS: ADM suppressed LPS-induced microglial M1 polarization, as reflected by downregulated iNOS and CD86 expression, and neuroinflammation, as reflected by decreased TNF-α, IL-1ß, and IL-6 expression, in a dose-dependent manner. Moreover, ADM inhibited microglia-induced neural apoptosis, as reflected by TUNEL assay results and the expression of apoptotic markers (C-Caspase3 and Bcl2), in a dose-dependent manner. EPO monotherapy displayed an effect similar to that of ADM monotherapy. Furthermore, ADM combined with EPO therapy exhibited greater effects than either monotherapy in terms of inhibiting microglial M1 polarization, neuroinflammation, and neural apoptosis. In vivo experiments confirmed the findings of the in vitro experiments and showed that ADM combined with EPO improved SCI functional recovery and neural injury compared with monotherapy. CONCLUSION: ADM combined with EPO improves recovery from SCI by suppressing microglial M1 polarization-mediated neural inflammation and apoptosis.


Assuntos
Eritropoetina , Traumatismos da Medula Espinal , Ratos , Animais , Microglia , Adalimumab/farmacologia , Doenças Neuroinflamatórias , Lipopolissacarídeos/farmacologia , Eritropoetina/farmacologia , Eritropoetina/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Inflamação/metabolismo , Apoptose , Fator de Necrose Tumoral alfa/metabolismo , Medula Espinal/metabolismo
15.
J Environ Sci (China) ; 130: 139-148, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37032030

RESUMO

Wastewater surveillance (WS) of SARS-CoV-2 currently requires multiple steps and suffers low recoveries and poor sensitivity. Here, we report an improved analytical method with high sensitivity and recovery to quantify SARS-CoV-2 RNA in wastewater. To improve the recovery, we concentrated SARS-CoV-2 viral particles and RNA from both the solid and aqueous phases of wastewater using an electronegative membrane (EM). The captured viral particles and RNA on the EM were incubated in our newly developed viral inactivation and RNA preservation (VIP) buffer. Subsequently, the RNA was concentrated on magnetic beads and inhibitors removed by washing. Without eluting, the RNA on the magnetic beads was directly detected using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Analysis of SARS-CoV-2 pseudovirus (SARS-CoV-2 RNA in a noninfectious viral coat) spiked to wastewater samples showed an improved recovery of 80%. Analysis of 120 wastewater samples collected twice weekly between May 2021 and February 2022 from two wastewater treatment plants showed 100% positive detection, which agreed with the results independently obtained by a provincial public health laboratory. The concentrations of SARS-CoV-2 RNA in these wastewater samples ranged from 2.4×102 to 2.9×106 copies per 100 mL of wastewater. Our method's capability of detecting trace and diverse concentrations of SARS-CoV-2 in complex wastewater samples is attributed to the enhanced recovery of SARS-CoV-2 RNA and efficient removal of PCR inhibitors. The improved method for the recovery and detection of viral RNA in wastewater is important for wastewater surveillance, complementing clinical diagnostic tests for public health protection.


Assuntos
COVID-19 , RNA Viral , Humanos , Águas Residuárias , SARS-CoV-2/genética , Vigilância Epidemiológica Baseada em Águas Residuárias
16.
Chemistry ; 28(10): e202102630, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35113460

RESUMO

In fabricating an artificial photosynthesis (AP) electrode for water oxidation, we have devised a semiconductor-mediator-catalyst structure that mimics photosystem II (PSII). It is based on a surface layer of vertically grown nanorods of Fe2 O3 on fluorine doped tin oxide (FTO) electrodes with a carbazole mediator base and a Ru(II) carbene complex on a nanolayer of TiO2 as a water oxidation co-catalyst. The resulting hybrid assembly, FTO|Fe2 O3 |-carbazole|TiO2 |-Ru(carbene), demonstrates an enhanced photoelectrochemical (PEC) water oxidation performance compared to an electrode without the added carbaozle base with an increase in photocurrent density of 2.2-fold at 0.95 V vs. NHE and a negatively shifted onset potential of 500 mV. The enhanced PEC performance is attributable to carbazole mediator accelerated interfacial hole transfer from Fe2 O3 to the Ru(II) carbene co-catalyst, with an improved effective surface area for the water oxidation reaction and reduced charge transfer resistance.


Assuntos
Fotossíntese , Água , Catálise , Oxirredução , Semicondutores , Água/química
17.
Analyst ; 147(11): 2508-2514, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35537201

RESUMO

Potential-resolved electrochemiluminescence (ECL) ratiometric analysis has become a research hotspot in bioassays by virtue of its good accuracy, versatility and specificity. Current ECL ratiometry mainly focuses on the competition for the co-reactant or quantitative analysis using a variable signal and a changeless signal; the disorganized change or small difference between the two signals may affect the accuracy and sensitivity of detection. In this study, we have developed a novel ECL ratiometric sensor based on the bidirectional regulation of two independent co-reaction systems by H2O2. H2O2 as a bidirectional moderator permits the ECL signals of the cathode and anode to independently change in opposite trends, which greatly enhances the organization and difference between the two signals. The ratio of the two signals is used to realize the quantitative analysis of myoglobin (MyO) with a good linear relationship between log(ECLcathode/ECLanode) and log CMyO in the range of 1.0 × 10-13 to 1.0 × 10-7 g mL-1. The detection limit is 4.0 × 10-14 g mL-1. Furthermore, it showed excellent performance in the determination of MyO in human serum samples. The proposed biosensor provides some developments for the sensitive and accurate detection of disease markers.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Humanos , Peróxido de Hidrogênio , Limite de Detecção , Medições Luminescentes
18.
Analyst ; 147(2): 247-251, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34931211

RESUMO

Herein, a novel and facile dual-wavelength ratiometric electrochemiluminescence-resonance energy transfer (ECL-RET) sensor for hydrogen sulfide (H2S) detection was constructed based on the interaction between S2- and Cd2+-doped g-C3N4 nanosheets (NSs). Cd2+-doped g-C3N4 NSs exhibited a strong ECL emission at 435 nm. In the presence of H2S, CdS was formed in situ on g-C3N4 NSs by the adsorption of S2- and Cd2+, generating another ECL emission at 515 nm. Furthermore, the overlapping of the absorption spectrum of the formed CdS and the ECL emission spectrum of g-C3N4 NSs led to a feasible RET, thus quenching the ECL intensity from g-C3N4 at 435 nm. Through an ECL decrease at 435 nm and an increase at 515 nm, a dual-wavelength ratiometric ECL-RET system for H2S was designed. The sensor exhibited a lower detection limit of 0.02 µM with a wide linear range of 0.05-100.0 µM. In addition, the applicability of the method was validated by plasma sample analysis with a linear range of 80.0-106.0%. We believe that such a proposal would provide new insight into advanced dual-wavelength ECL ratiometric assays.


Assuntos
Técnicas Biossensoriais , Sulfeto de Hidrogênio , Cádmio , Técnicas Eletroquímicas , Limite de Detecção , Medições Luminescentes
19.
Org Biomol Chem ; 20(39): 7840-7844, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36172809

RESUMO

An electrochemical-oxidation-induced intramolecular annulation used for the synthesis of imidazole was developed under undivided electrolytic conditions. In an undivided cell, amines, alkynes and azides could smoothly participate in the transformation to furnish a variety of substituted imidazoles through the tandem Michael addition/azide/cycloamine reaction. The reaction could be easily handled and avoided the use of both transition metal catalysts and peroxide reagents, which is in line with the concept of green chemistry.


Assuntos
Azidas , Nitroimidazóis , Alcinos/química , Aminas , Antifúngicos , Azidas/química , Catálise , Ciclização , Imidazóis/química , Estrutura Molecular , Peróxidos
20.
World J Surg ; 46(12): 2973-2983, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36216895

RESUMO

BACKGROUND: We aimed to compare multifunctional irrigation-assisted vacuum drainage (MIVD), vacuum sealing drainage (VSD) and the Penrose drain in treating severe multi-space deep fascial infection (DFI) in head and neck. METHODS: A retrospective study was conducted on 113 patients who had suffered from severe multi-space DFI in head and neck and underwent surgical treatment. Patients were divided into the MIVD group, the VSD group, and the Penrose group according to their treatment. Baseline characteristics and clinical outcome data regarding infection control, clinicians' workload, surgical procedure required, and cost were analyzed. RESULTS: Duration of antibiotic administration was significantly shorter using MIVD and VSD than Penrose drains (p = 0.002 with MIVD, p = 0.008 with VSD). Hospital stay in the MIVD group was shorter than the Penrose group (p = 0.034). Compared to the other two groups, more times of manual irrigation were needed in higher frequency in the Penrose group (p < 0.001). Longer Incision and more surgical operation were required in the VSD group than the other two groups (p < 0.001). The treatment cost in the VSD group was higher than the MIVD group (p = 0.045) and the Penrose group (p < 0.001). CONCLUSIONS: In the treatment of severe multi-space DFI in head and neck, MIVD and VSD are superior to the Penrose drain in infection control and reduction in clinicians' workload. Meanwhile, MIVD, with fewer surgical procedures required and less cost, seems to be a more promising method than VSD.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Humanos , Tratamento de Ferimentos com Pressão Negativa/métodos , Estudos Retrospectivos , Drenagem/métodos , Vácuo , Pescoço
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