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1.
Front Public Health ; 9: 670889, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34490178

RESUMO

COVID-19, the coronavirus disease 2019; SARS-CoV-2, the coronavirus 2; ACE2, angiotensin converting enzyme 2; S protein, spiked glycoprotein; TMPRSS2, transmembrane serine protease 2; WHO, World Health Organization. Purpose: Although the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2, has been viably controlled in China, a new normal in healthcare strategies has become standard in China and worldwide. We conducted a questionnaire study to disseminate the experience from China in terms of urology outpatient prevention and control measures under standardized prevention policies against COVID-19. Participants and Methods: From May 3, 2020 to June 25, 2020, we conducted an anonymous cross-sectional questionnaire study, focused on the status of and experiences with outpatient urology prevention and control measures during the COVID-19 pandemic. The targeted respondents were urologists in mainland China, covering all levels of hospitals and clinics. Results: A total of 216 (97%) valid responses were collected. We found that 183 (85%) respondents were from outside of Hubei province in China. One-hundred-and-fifty-eight (73%) respondents believed that SARS-CoV-2 could be detected in urine, and that protection against urine exposure was needed. Over 80% of respondents recommended WeChat application or similar online video meetings for virtual outpatient consultations. The suggested flowcharts and recommendations to prevent new cases were easy to understand and approved by most physicians, which could provide reference for outpatient prevention and control. We still need to make adequate preparations under the new normal of the COVID-19 Epidemic, especially for those suspected of being infected. Conclusions: Although the scientific validation of the questionnaire is limited, it provides a first snapshot of the experiences relating to the prevention and control measures in urology clinics in China, and can inform future policies in this field.


Assuntos
COVID-19 , Urologia , China/epidemiologia , Estudos Transversais , Humanos , Pandemias , SARS-CoV-2 , Inquéritos e Questionários
2.
Analyst ; 145(15): 5260-5265, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32618292

RESUMO

Perylene and its derivatives, as classical organic polycyclic aromatic hydrocarbon (PAH) ECL materials, have attracted extensive attention due to their excellent photoelectric activity and good structural controllability. As is well-known, the molecular structure of perylene is composed of five coplanar aromatic rings. There are intense π-π stacking interactions between perylene molecules, which lead to their aggregation and poor solubility in aqueous media. Unfortunately, this aggregation can weaken or even quench the emission intensity of perylene owing to the aggregation-caused quenching (ACQ) effect, finally limiting the analytical application of perylene in biological detection. In this work, perylene composite microcrystals (ETTA@Pe MCs) doped with non-planar molecular tetrakis(4-aminophenyl)ethene were synthesized in the aqueous phase by a surfactant-assisted self-assembly method. During this process, the intense π-π stacking interactions between perylene monomers were suppressed by doping. As a result, the ETTA@Pe MCs exhibited a significantly enhanced ECL signal as compared to that of perylene microcrystals (Pe MCs) in the presence of S2O82- as a co-reactant. Moreover, the ETTA@Pe MCs were utilized as a novel electrochemiluminescent (ECL) luminophores to fabricate a sensitive ECL biosensor for the quantitative analysis of dopamine (DA), which displayed a favorable linear response from 1 to 100 µmol L-1 with a detection limit of 0.96 nmol L-1.


Assuntos
Técnicas Biossensoriais , Perileno , Técnicas Eletroquímicas , Etilenos , Medições Luminescentes
3.
Chem Commun (Camb) ; 56(63): 9000-9003, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32638738

RESUMO

A kind of organic microcrystal, 9,10-diphenylanthracene microcrystals (DPA MCs), was developed as a novel electrochemiluminescence (ECL) coreactant accelerator to efficiently catalyze dissolved O2 for more reactive oxygen species (ROSs) generation, achieving intense ECL for a H2O2-free luminol system. Moreover, based on this ternary ECL system, a signal "off-on" ECL biosensor for microRNA-21 (miRNA-21) detection was constructed combining a sensitive target recycling amplification strategy and an enzyme-mediated recycling strand displacement reaction (RSDR).


Assuntos
Técnicas Biossensoriais/métodos , Luminol/química , MicroRNAs/análise , Antracenos/química , Catálise , Linhagem Celular Tumoral , Humanos , Medições Luminescentes , Técnicas de Amplificação de Ácido Nucleico , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo
4.
Appl Opt ; 58(27): 7375-7378, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674386

RESUMO

In this paper, an integrated processing method was demonstrated to fabricate the polymer-based thermo-optic (TO) switch with low power consumption. The characteristic parameters of the switch were carefully designed and simulated. The air trench structure was exploited to reduce the power consumption, which can be formed with the waveguide simultaneously by the integrated processing method. Moreover, the introduced polymer/silica hybrid waveguide structure can also improve the response time of the device. A typical fabricated switch presented a low switching power of 5.2 mW. The measured switching rise time and fall time are 192.2 and 201.1 µs, respectively.

5.
Anal Chem ; 91(5): 3710-3716, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30724078

RESUMO

Apart from the reported energy transfer mechanism of aggregation-induced electrochemiluminescence (AI-ECL) enhancement, a new strategy named restriction of intramolecular motions-driven ECL (RIM-ECL) enhancement is first proposed based on the phenomenon of a very strong electrochemiluminescence observed on the hexagonal tetraphenylethylene microcrystals (TPE MCs) in aqueous solution. Compared to TPE in molecule-isolation state with faint ECL, TPE in aggregate state (TPE MCs) showed a significantly enhanced ECL that was due to the restriction of intramolecular motions (RIM). Inspired by the unique luminescence characteristic of TPE MCs, we integrated the novel ECL emitter of TPE MCs and target-activated bipedal DNA walker together to fabricate a sensitive "off-on" ECL biosensor for Mucin 1 (MUC1) assay, which exhibited desirable linear response for a concentration scope from 1 fg/mL to 1 ng/mL with a low detection limit of 0.29 fg/mL. The RIM enhanced ECL demonstrated by the TPE MCs provides a new chapter in the exploration of aggregated organic emitters for further applications.


Assuntos
Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Movimento (Física) , Mucina-1/análise , Estilbenos/química , Animais , Técnicas Biossensoriais , Cristalização , Humanos , Limite de Detecção , Luminescência , Soluções
6.
ACS Appl Mater Interfaces ; 10(44): 38648-38655, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30360081

RESUMO

The accurate and rapid quantitative detection of antibodies had a significant influence in controlling and preventing disease or toxin outbreaks. In this work, we first introduce the antibody-powered triplex-DNA nanomachine to release cargo DNA as a substitute target for sensitive electrochemiluminescence (ECL) detection of anti-digoxigenin based on a novel ternary ECL system. It is worth noting that the cargo DNA as a substitute target of antibody can further participate in an enzyme-assisted cycling strand displacement reaction to achieve ECL signal amplification and improve the sensitivity of antibody detection. Additionally, porous palladium nanospheres with a considerable catalytic activity were first applied as a coreaction accelerator to efficiently enhance the intensity of the ECL system of rubrene microblocks as luminophore and dissolved O2 as an endogenous coreactant. With the resultant ternary ECL system as a biosensing platform, a significantly enhanced initial signal was achieved in advance. Then, the ferrocene-labeled quenching probes were employed to reduce initial signal and obtain the low-background signal. Eventually, the cargo DNA made the quenching probes release and recover the signal in the presence of anti-digoxigenin. Thereupon, the wide linear range (0.01-200 nM) and low limit of detection (6.7 pM) were obtained, and this method not only reduces conjugation steps but also provides a sensitive and novel ECL analysis platform for the trace detection of other antibodies and antigen.


Assuntos
Técnicas Biossensoriais , DNA/química , Digoxigenina/isolamento & purificação , Nanoestruturas/química , Anticorpos/química , Digoxigenina/química , Técnicas Eletroquímicas , Luminescência , Medições Luminescentes , Naftacenos/química
7.
Environ Toxicol Chem ; 30(10): 2202-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21766319

RESUMO

A Pseudomonas strain (TeU), resistant to tellurite (TeO(2)(3)(-) and cadmium (Cd(2+)) ions, was isolated from heavy-metal-contaminated sediments by enrichment. Black precipitates, presumably the product of the reduction of tellurite, such as tellurium, occurred in cultures of the isolate after growth in medium containing tellurite. Quantitative determination of the TeO(2)(3)(-) concentration in the liquid culture demonstrated a decreased concentration of tellurite (to less than 100 µM) from initial concentrations of approximately 1,000 µM within 24 h of growth. Strain TeU was resistant to TeO(2)(3)(-) and Cd(2+) concentrations as high as 2,000 µM and 500 µM, respectively. Transposon mutagenesis of strain TeU resulted in mutants exhibiting Cd(2+) sensitivity (Strain BU21) and one with decreased ability to reduce tellurite (strain AU08). Strain BU21 was less tolerant to Cd(2+) (100 µM) compared with the wild-type strain TeU (500 µM) but was still able to reduce tellurite to 80% of that of strain TeU. Although strain AU08 possesses the ability for Cd(2+) resistance, it reduced less than 20% of the initial concentrations of tellurite compared with strain TeU. Genes encoding an HflKC complex and a putative metallopeptidase were associated with the bacterium's capacity for tellurite reduction and Cd resistance, respectively. The ability to reduce tellurite therefore may not be necessary for this bacterium's heavy metal and metalloid tellurite resisting ability.


Assuntos
Cádmio/farmacologia , Pseudomonas/isolamento & purificação , Telúrio/farmacologia , Genes Bacterianos , Sedimentos Geológicos/microbiologia , Metaloproteases/genética , Mutagênese , Fenótipo , Pseudomonas/efeitos dos fármacos , Pseudomonas/genética , Telúrio/metabolismo
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