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1.
Biosens Bioelectron ; 197: 113783, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775254

RESUMO

Dynamic DNA nanodevices-based assembly is currently well developed for a broad range of analytical applications. However, some problems persist, such as false positives, nuclease digestions, and exclusive interferences with single signal in complex cellular environment. Herein, we have established a method for imaging cellular miR-155, where it induced assembly of two tetrahedral DNA frameworks (TDFs), TDF-1 and TDF-2, both of which had four fluorescence modified hairpins (Cy3 for TDF-1 and Cy5 for TDF-2, respectively) at each angle, into polymeric tetrahedral DNA frameworks (PTDFs). The formation of PTDFs was greatly dependent on miR-155 overexpressed in breast cancer cells since miR-155 drove catalytic hairpin assembly (CHA) reaction by opening the hairpins at the vertices of TDF-1 to hybridize with TDF-2. Upon the completion of hybridization, the miR-155 was released, starting the next cycle of the CHA reaction. Measurements of atomic force microscopy (AFM) and Förster resonance energy transfer (FRET) showed that the formation of PTDFs occurred owing to the multivalent assembly of TDF-1 and TDF-2. By utilizing the formation of PTDFs, miR-155 was detected in a linear range from 0.5 nM to 30 nM with a 0.35 nM limit of determination, enabling the successful imaging of endogenous miR-155 in live cells through the FRET signal from Cy3 to Cy5. These studies demonstrated that this method significantly strengthened the resistance nuclease to digestion and stable ability with exclusive interference.

2.
Anal Chem ; 93(46): 15331-15339, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34756034

RESUMO

DNA logic nanodevices have prospects in molecular recognitions but still face challenges in achieving DNA computation-controlled regulation in specific compartments of living cells. By incorporating the i-motif sequence and ATP aptamers into a Y-shaped DNA (Y-DNA) structure, and applying gold nanoparticles (AuNPs) as the transporting carrier, herein we present a new type of DNA logic nanodevices to monitor the ATP levels in lysosomes of living cells. Triple energy transfers including dual fluorescent resonance energy transfers (FRETs) and a nanometal surface energy transfer (NSET) occurred in the DNA logic nanodevices. It was identified that the proposed nanodevices perform an AND logic operation to output FRET signals only when an endogenous proton and ATP simultaneously exist in the cellular microenvironment. Owing to the use of the i-motif sequence, the nanodevices have lysosome-recognizing capacity without causing alkalization of the acidic organelle, making DNA computation-controlled regulation at the level of cellular organelles achievable. These DNA logic nanodevices show high application prospects in lysosome-related cellular function and disease treatment.

3.
ACS Appl Mater Interfaces ; 13(42): 49754-49761, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34657424

RESUMO

A reliable and sensitive detection approach for SARS-CoV 2 is essential for timely infection diagnosis and transmission prevention. Here, a two-dimensional (2D) metal-organic framework (MOF)-based photoelectrochemical (PEC) aptasensor with high sensitivity and stability for SARS-CoV 2 spike glycoprotein (S protein) detection was developed. The PEC aptasensor was constructed by a plasmon-enhanced photoactive material (namely, Au NPs/Yb-TCPP) with a specific DNA aptamer against S protein. The Au NPs/Yb-TCPP fabricated by in situ growth of Au NPs on the surface of 2D Yb-TCPP nanosheets showed a high electron-hole (e-h) separation efficiency due to the enhancement effect of plasmon, resulting in excellent photoelectric performance. The modified DNA aptamer on the surface of Au NPs/Yb-TCPP can bind with S protein with high selectivity, thus decreasing the photocurrent of the system due to the high steric hindrance and low conductivity of the S protein. The established PEC aptasensor demonstrated a highly sensitive detection for S protein with a linear response range of 0.5-8 µg/mL with a detection limit of 72 ng/mL. This work presented a promising way for the detection of SARS-CoV 2, which may conduce to the impetus of clinic diagnostics.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Estruturas Metalorgânicas/química , SARS-CoV-2/química , Glicoproteína da Espícula de Coronavírus/análise , Sequência de Bases , Técnicas Biossensoriais/instrumentação , COVID-19/diagnóstico , DNA/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Ouro/efeitos da radiação , Humanos , Ácidos Nucleicos Imobilizados/química , Luz , Limite de Detecção , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Faringe/virologia , Processos Fotoquímicos , Porfirinas/química , Glicoproteína da Espícula de Coronavírus/química , Itérbio/química
4.
Analyst ; 146(23): 7187-7193, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34714303

RESUMO

The expression level of nucleic acids is closely related to a variety of diseases. Herein, a highly sensitive detection of a nucleic acid based on a CoOOH-luminol chemiluminescence (CL) system without the addition of oxidants was proposed by the toehold-mediated strand displacement reaction (TSDR) and the liposome dual signal amplification strategy with the hybrid probe formed by linking soft nanoballs (SNBs) to magnetic beads (MBs) through DNA hybridization. Inspired by the free radical scavenging effect of the as-prepared carbon dots (CDs), CDs were successfully employed to quench the CL intensity of the CoOOH-luminol system. And the CDs were further encapsulated into liposomes to construct SNBs, which avoided the complex modification of CDs to maintain their original properties, as well as loaded a large number of CDs to scavenge free radicals to achieve signal amplification. Based on this, target DNA (tDNA) could be sensitively detected based on the reduced CL intensity, which achieved a dynamic detection range from 0.1 nM to 20 nM with a limit of detection as low as 59 pM (3σ/k), showing amazing promise in the biosensing of nucleic acid biomarkers.

5.
Anal Chem ; 93(43): 14545-14551, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34689544

RESUMO

MicroRNAs (miRNAs) are found in extremely low concentrations in cells, so highly sensitive quantitation is a great challenge. Herein, a simple dual-amplification strategy involving target-activated catalytic hairpin assembly (CHA) coupled with multiple fluorophores concentrated on one X-shaped DNA is reported. In this strategy, four hairpin probes (H1, H2, H3, and H4) are modified with FAM and BHQ1 at both sticky ends, while a circulating hairpin probe (H0) is used to activate CHA circuits once it binds to complementary sequences in the target miR-21 (T). The powerful dual-amplification cascades in Förster resonance energy transfer (FRET)-based nonenzymatic nucleic acid circuits are triggered by T-H0-activated formation of the X-shaped DNA nanostructure, freeing T-H0 for the next CHA reaction cycle. CHA circuits increase the fluorescence due to the wide distance between FAM and BHQ1 in the formed X-shaped DNA nanostructure, resulting in signal amplification and highly sensitive detection of miR-21, with a limit of detection (LOD, 3σ) of 0.025 nM, which is 25.6 or 57.6 times lower than that obtained through a single-amplification strategy without multiple fluorophores on one X-shaped DNA or CHA circuit. Furthermore, this cascade reaction was completed in 45 min, effectively avoiding target degradation. This new enzyme-free signal amplification strategy holds promising potential for sensitively detecting different DNA or RNA sequences by simply adapting the fragment of the H0 sequence complementary to the target.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , MicroRNAs , Nanoestruturas , DNA , Limite de Detecção
6.
Int J Biol Macromol ; 190: 206-213, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34492243

RESUMO

Easy deactivation of free enzymes under non-native condition has become a stumbling block to the industrial application of biocatalysis. Natural deep eutectic solvent (NADES) has been exploited as a novel reaction medium for improving enzyme stability. The present work focused on preserving and enhancing the activity of carbonic anhydrase (CA) in a more economical and biocompatible NADES system. We synthesized six choline chloride/betaine-based NADES and analyzed the effects of compositions and concentrations of NADES on their physicochemical properties. The Bet-Gly (1: 2) NADES (55%) was proved to be more suitable as reaction medium for CA by analyzing enzyme activity in the presence of NADES. The enhancement in the stability of CA was found to be as a result of a three-dimensional hydrogen bonding network, rather than the individual or the synergistic effect of betaine and glyceride. The conformational change of CA to become more compact was confirmed both by fluorescence spectrum analysis and circular dichroism analysis. It is worth mentioning that a remarkable thermal stability was maintained when CA was incubated at temperature below 60 °C, and about 96% of activity was still restored in 55% NADES at 60 °C for 12 h.

7.
Exp Ther Med ; 22(5): 1250, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34539846

RESUMO

The clinical characteristics and risk factors of patients with coronavirus disease 2019 (COVID-19) with re-positive or false-negative test results have so far remained to be determined. The present study provides a cross-sectional observational study on 134 hospitalized patients selected from Huoshenshan Hospital (Wuhan, China) using cluster sampling. A total of 68 patients had reduced red blood cell (RBC) counts, 55 a decrease in the hemoglobin concentration (HBC) and 73 a decline in hematocrit (HCT). The false-negative rate of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA detection in pharyngeal swab specimens was 18.7%. The absolute lymphocyte count (ALC), RBC, HBC and HCT levels in false-negative patients were significantly higher than those in patients who tested positive for viral nucleic acids. Multivariate logistic regression analysis indicated that RBC [odds ratio (OR)=0.43, 95% CI: 0.18-0.99], HBC (OR=0.97, 95% CI: 0.94-0.99) and ALC (OR=0.43, 95% CI: 0.20-0.91) were the factors influencing the negative testing results for viral nucleic acid. The rate of re-positive patients was 16.4%. The white blood cell, RBC, HBC and HCT values in re-positive patients were lower than those in non-re-positive patients. The median (interquartile range) values for RBC, HBC and HCT of male re-positive patients were 3.95 (3.37, 4.2) x1012/l, 123 (103, 133) g/l and 36.6 (31.1, 39.2)%, respectively, while the RBC, HBC and HCT of female re-positive patients were 3.54 (3.13, 3.74) x1012/l, 115 (102, 118) g/l and 34.2 (28.5, 34.9)%, respectively. It was determined that RBC, HBC and HCT values had moderate accuracy in predicting SARS-CoV-2 recurrence in patients with COVID-19 using receiver operating curve analysis. The present study suggested that RBC may have an important role in the pathogenesis of COVID-19.

8.
Virol Sin ; 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34224111

RESUMO

Zika virus (ZIKV) infection could disrupt neurogenesis and cause microcephaly in neonates by targeting neural progenitor cells (NPCs). The tumor suppressor p53-mediated cell cycle arrest and apoptotic cell death have been suggested to be activated upon ZIKV infection, yet the detailed mechanism is not well understood. In the present study, we investigated the effects of ZIKV-encoded proteins in the activation of p53 signaling pathway and found that, among the ten viral proteins, the nonstructural protein 5 (NS5) of ZIKV most significantly activated the transcription of p53 target genes. Using the immunoprecipitation-coupled mass spectrometry approach, we identified that ZIKV-NS5 interacted with p53 protein. The NS5-p53 interaction was further confirmed by co-immunoprecipitation and GST pull-down assays. In addition, the MTase domain of NS5 and the C-terminal domain of p53 were mapped to be responsible for the interaction between these two proteins. We further showed that ZIKV-NS5 was colocalized with p53 and increased its protein level in the nuclei and able to prolong the half-life of p53. Furthermore, lentivirus-mediated expression of ZIKV-NS5 in hNPCs led to an apparent cell death phenotype. ZIKV-NS5 promoted the cleavage of PARP1 and significantly increased the cell apoptosis of hNPCs. Taken together, these findings revealed that ZIKV-NS5 is a previously undiscovered regulator of p53-mediated apoptosis in hNPCs, which may contribute to the ZIKV-caused abnormal neurodevelopment.

9.
Front Neurol ; 12: 619631, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054684

RESUMO

Objective: The striatum is unevenly impaired bilaterally in Parkinson's disease (PD). Because the striatum plays a key role in cortico-striatal circuits, we assume that lateralization affects cortico-striatal functional connectivity in PD. The present study sought to evaluate the effect of lateralization on various cortico-striatal circuits through resting-state functional magnetic resonance imaging (fMRI). Methods: Thirty left-onset Parkinson's disease (LPD) patients, 27 right-onset Parkinson's disease (RPD) patients, and 32 normal controls with satisfactory data were recruited. Their demographic, clinical, and neuropsychological information was collected. Resting-state fMRI was performed, and functional connectivity changes of seven subdivisions of the striatum were explored in the two PD groups. In addition, the associations between altered functional connectivity and various clinical and neuropsychological characteristics were analyzed by Pearson's or Spearman's correlation. Results: Directly comparing the LPD and RPD patients demonstrated that the LPD patients had lower FC between the left dorsal rostral putamen and the left orbitofrontal cortex than the RPD patients. In addition, the LPD patients showed aberrant functional connectivity involving several striatal subdivisions in the right hemisphere. The right dorsal caudate, ventral rostral putamen, and superior ventral striatum had decreased functional connectivity with the cerebellum and parietal and occipital lobes relative to the normal control group. The comparison between RPD patients and the controls did not obtain significant difference in functional connectivity. The functional connectivity between the left dorsal rostral putamen and the left orbitofrontal cortex was associated with contralateral motor symptom severity in PD patients. Conclusions: Our findings provide new insights into the distinct characteristics of cortico-striatal circuits in LPD and RPD patients. Lateralization of motor symptoms is associated with lateralized striatal functional connectivity.

10.
Talanta ; 228: 122270, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773718

RESUMO

Excess free copper in serum has been identified to induce neurodegenerative diseases such as Alzheimer's disease, thus it is very important to determine copper (II) ions (Cu2+) content for human health test. Herein we developed a point-of-care testing (POCT) platform through a luminescence "on-off" recognition mechanism of serum copper. Microsized europium coordination polymer particles (Eu-CPs), which was prepared with citric acid (CA) and europium nitrate hexahydrate through a hydrothermal route, were then successfully loaded with the mixture of 2,6-pyridinedicarboxylic acid (DPA) and poly(vinyl alcohol) (PVA) to form electrospun nanofibrous films (ENFFs). The as-prepared Eu-CPs/DPA/PVA ENFFs exhibited red emission at 618 nm when exciting at 280 nm, with the quantum yields of 22.2% owing to the antenna effect from DPA to Eu3+. Furthermore, the strong luminescence could be selectively quenched by Cu2+ through coordination with DPA to interrupt the antenna effect. With that, Cu2+ was successfully detected in the range of 2-45 µM with a detection of limit of 1.3 µM, well matching with the requirement of clinic test of excess free copper induced neurodegenerative diseases. As a proof of concept at last, this POCT platform was used to detect free copper in spiked serum samples with a recovery of 101.1%-105.2%, demonstrating that this platform provides significant potential for use in clinical test.

11.
Chem Commun (Camb) ; 57(26): 3211-3214, 2021 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-33644788

RESUMO

Here we report a chirality transfer of cysteine, which at first was to the plasmonic resonance region of gold nanobipyramids and then to that of Ag nanoshells with increasing growth of Ag layers, owing to the important role of the free Cys embedded within the Ag nanoshell. Our finding is helpful for developing new chiral plasmonic nanomaterials with the best designed asymmetric properties.

12.
Analyst ; 146(5): 1675-1681, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33624639

RESUMO

DNA-based nanomachines have aroused tremendous interest because of their potential applications in bioimaging, biocomputing, and diagnostic treatment. Herein, we constructed a novel exonuclease III-propelled and signal-amplified stochastic DNA walker that autonomously walked on a spherical particle-based 3D track through a burnt-bridge mechanism, during which nanosurface energy transfer (NSET) occurred between the fluorescent dye modified on hairpin DNA and the surface of gold nanoparticles (AuNPs). As a proof of concept, this stochastic DNA walker achieves prominent detection performance of HIV DNA in the range of 0.05-1.2 nM with a detection limit of 12.7 pM and satisfactory recovery in blood serum, showing high promise in biosensing applications with complicated media.


Assuntos
Técnicas Biossensoriais , Infecções por HIV , Nanopartículas Metálicas , DNA/genética , Transferência de Energia , Exodesoxirribonucleases/metabolismo , Ouro , Humanos , Limite de Detecção , Andadores
13.
Neurol Sci ; 42(1): 159-166, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32572660

RESUMO

OBJECTIVE: To determine the impact of smoking status in the prediction of stroke using CHADS2 and CHA2DS2-VASc schemes. METHODS: Five hundred twenty-eight consecutive patients with arrhythmic symptoms and without any documented arrhythmia from Queen Mary Hospital, Hong Kong, were followed up to determine the incidence of ischemic stroke, new-onset atrial fibrillation (AF), or all-cause mortality. Smoking status was classified into nonsmokers and smokers. The pairwise comparisons of C-statistics for outcomes were performed. RESULTS: During a median follow-up period of 6.2 years, 65 (12.3%) individuals developed ischemic stroke. Smokers experienced higher annual incidence of stroke, a new-onset AF, and all-cause death compare to nonsmokers, with corresponding hazard ratio (HR) of stroke, AF, and all-cause death being 2.51 (95% confidence intervals, CI 1.36als, CIse death bein 1.15a3.24), and 1.95 (95% CI 1.161.95 (95% CIath being 2.51 (95% confidence corr2 and CHA2DS2-VASc for stroke were 0.60 (95% CI 0.51 for stp = 0.09) and 0.59 (95% CI 0.50 (95%, p = 0.15) respectively, whereas the C-statistics of CHADS2 and CHA2DS2-VASc were 0.66 (95% CI 0.61 were 0p = 0.005), 0.75 (95% CI 0.7 CI 0.7p < 0.0001), respectively among nonsmokers. After incorporating smoking, both the CHADS2-smoking and CHA2DS2-VASc-smoking achieved better C-statistics for new-onset ischemic stroke prediction superior to baseline score systems in male groups. CONCLUSION: Cigarette smoking status has impact on stroke stratification using CHADS2 and CHA2DS2-VASc scheme. The discrimination of the CHADS2 and CHA2DS2-VASc scheme for stroke can be significantly improved if smoking status is additionally considered.


Assuntos
Fibrilação Atrial , Fumar Cigarros , Acidente Vascular Cerebral , Humanos , Masculino , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
14.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(5): 541-545, 2020 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-33085239

RESUMO

OBJECTIVE: This study aims to evaluate the clinical effect of oral repair membrane and ß-tricalcium phosphate (ß-TCP) on the treatment of jaw cyst. METHODS: A retrospective analysis was performed on 81 cases of jaw cysts, and clinical data were collected for the comparison of traditional surgical curettage (group A, 27 cases), biofilm covering bone wounds after curettage (group B, 27 cases), and ß-TCP filling combined with biofilm covering. RESULTS: No recurrence occurred in 81 patients, and no significant difference in preoperative CT value among the three groups (P<0.05). Follow-up CT reexamination 3, 6, and 12 months after operation showed significant differences among the three groups of CT values (P<0.05). Group C was better than Group B or Group A (P<0.05). CONCLUSIONS: In traditional jaw cyst curettage, the application of biofilm exhibited good osteogenesis effect, and the combined application of ß-TCP and biofilm exerted a better effect.


Assuntos
Fosfatos de Cálcio , Cistos Maxilomandibulares , Humanos , Osteogênese , Estudos Retrospectivos
15.
Front Immunol ; 11: 1926, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983119

RESUMO

Innate immunity is the first-line defense against antiviral or antimicrobial infection. RIG-I and MDA5, which mediate the recognition of pathogen-derived nucleic acids, are essential for production of type I interferons (IFN). Here, we identified mitochondrion depolarization inducer carbonyl cyanide 3-chlorophenylhydrazone (CCCP) inhibited the response and antiviral activity of type I IFN during viral infection. Furthermore, we found that the PTEN-induced putative kinase 1 (PINK1) and the E3 ubiquitin-protein ligase Parkin mediated mitophagy, thus negatively regulating the activation of RIG-I and MDA5. Parkin directly interacted with and catalyzed the K48-linked polyubiquitination and subsequent degradation of RIG-I and MDA5. Thus, we demonstrate that Parkin limits RLR-triggered innate immunity activation, suggesting Parkin as a potential therapeutic target for the control of viral infection.


Assuntos
Proteína DEAD-box 58/metabolismo , Imunidade Inata , Helicase IFIH1 Induzida por Interferon/metabolismo , Mitocôndrias/imunologia , Receptores Imunológicos/metabolismo , Vírus Sendai/imunologia , Ubiquitina-Proteína Ligases/metabolismo , Vesiculovirus/imunologia , Células A549 , Animais , Chlorocebus aethiops , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Hidrazonas/farmacologia , Imunidade Inata/efeitos dos fármacos , Interferon Tipo I/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/virologia , Mitofagia , Proteínas Quinases/metabolismo , Células RAW 264.7 , Vírus Sendai/genética , Vírus Sendai/patogenicidade , Células THP-1 , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Desacopladores/farmacologia , Células Vero , Vesiculovirus/genética , Vesiculovirus/patogenicidade
16.
Talanta ; 219: 121203, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887110

RESUMO

The rapid and sensitive assay is the goal for advancing analytical methods and techniques to save time and achieve the early diagnosis, which are of crucial importance in clinic. The concept of synergistic effects for fastening reaction and improving sensitivity was constructed by introducing iodide (I-) to the typical Fenton's reaction system as a model reaction, which was calculated theoretically and demonstrated experimentally. In an acid medium, the simultaneous presence of Fe2+ and I- could significantly improve the oxidation capability and rate of H2O2 to etch gold nanorods (AuNRs) because of the synergistic effect, which was further successfully applied to the rapid and sensitive assay of cholesterol, glucose and uric acid in human serum. In this work, the synergistic effect greatly improved the reaction rate and sensitivity, which showed potential applications in biological sensing and clinic diagnosis.


Assuntos
Ouro , Nanotubos , Colorimetria , Glucose , Humanos , Peróxido de Hidrogênio
17.
Anal Chem ; 92(17): 11565-11572, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32786463

RESUMO

Fluorescent labeled single-stranded DNA (ssDNA) molecules physisorbed on graphene oxide (GO) have been extensively explored as a useful sensing platform. However, this approach faces challenges when applied to complex biological samples due to heavy nonspecific desorption of nontarget molecules from GO. To overcome this problem, we introduced a capture DNA (cDNA) fragment with a poly adenine (poly-A) extension into the physisorption system that greatly reduces nonspecific desorption and false positive signal due to strong binding between poly-A and GO. Fluorescence from the dye can be effectively quenched by BHQ, which thus provides a second guarantee of anti-interference to avoid possible nonspecific poly-A DNA displacement. As a proof of concept, we have successfully developed a novel DNA-adsorbing GO nanocomplex probe (DNA-GO nanocomplex probe). This probe has a high anti-interference capability and low background due to the presence of both GO and black hole quencher (BHQ) as a dual-quencher that reduces the background in live cell imaging due to resonance energy transfer (RET). We then employed the DNA-GO nanocomplex probe for simultaneous detection of miR-630 and miR-21 and also for simultaneous in situ dynamic monitoring of intracellular miR-630 and miR-21 in apoptotic cells. We discovered that miR-630 expression was up-regulated during the first 120 min. This simple but powerful protocol has great potential in precise detection and imaging of various substances in complex biological samples with improved accuracy.


Assuntos
Sondas de DNA/química , DNA de Cadeia Simples/química , Grafite/química , MicroRNAs/análise , Nanoestruturas/química , Adsorção , Apoptose , Técnicas Biossensoriais , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Humanos , Imagem Óptica , Propriedades de Superfície
18.
Front Neurol ; 11: 727, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849201

RESUMO

Objective: Motor asymmetry is characteristic in Parkinson disease (PD). This phenomenon is originated from uneven degeneration of bilateral substantia nigra. However, this asymmetry may not restrict to substantia nigra or striatum. We aimed to determine the effect of asymmetry on spontaneous brain activity across the whole brain. Methods: We consecutively recruited 71 patients with PD, as well as 35 healthy controls, and collected relevant demographic, clinical, and neuropsychological information. The PD patients were divided into two groups according to the side of motor symptom onset. All the participants underwent resting-state functional magnetic resonance imaging, and spontaneous brain activity was assessed using amplitude of low-frequency fluctuation (ALFF). The associations between areas showing significant group differences and various clinical and neuropsychological measures were analyzed. Results: Finally, the data of 30 PD patients with left-onset (LPD), 27 PD patients with right-onset (RPD), and 32 healthy controls were obtained. The three groups had similar age and gender ratios. Our results demonstrated that LPD patients had increased ALFF in the left inferior temporal gyrus and decreased ALFF in bilateral thalamus and cerebellum anterior lobes than the control group. The value of ALFF of the left inferior temporal gyrus was correlated with motor function, and ALFF value of the thalamus was associated with cognition. Comparisons between LPD and RPD patients and between RPD patients and the controls did not yield significant difference. Conclusions: The present study provides new insights into the distinct characteristics of spontaneous brain activity in LPD, which may be associated with motor and cognitive function.

19.
Anal Chem ; 92(19): 13118-13125, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32841018

RESUMO

As an important biomarker for early diagnosis of cancers, sensitive detection and high-resolution imaging of microRNA-21 in cancer cells have become important and challengeable. In this work, highly sensitive detection and spatial imaging of intracellular microRNA-21 were realized by the reduced signal background through vertical polarization excitation with a polarizer. The lateral local surface plasmon resonance property of gold nanorods (AuNRs) displayed a pronounced green color with low scattering intensity, which was adjusted to red color with strong scattering intensity when the core-satellite gold nanoparticle (AuNP) assembly was constructed on the side of AuNRs through a catalyzed hairpin assembly (CHA) circuit in the presence of microRNA-21. This unique approach allows for effectively reducing the strong background signal to improve the sensitivity of detection. Additionally, the proposed strategy can not only realize the sensitive detection of microRNA-21 with the limit of detection as low as 2 pM (3σ) but also achieve the high spatial imaging of cancer cells, which provided a specific strategy for the construction and imaging of intracellular imaging probes. It is believed that the simple and sensitive approach on the basis of lateral local surface plasmon resonance property of anisotropic AuNRs with excellent sensitivity combined with high spatial imaging holds promising potentials to visualize intracellular microRNAs with low abundance.


Assuntos
Técnicas Biossensoriais , Ouro/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Imagem Óptica , Ressonância de Plasmônio de Superfície , Anisotropia , Células Cultivadas , Células Hep G2 , Humanos
20.
Eur J Nucl Med Mol Imaging ; 47(11): 2525-2532, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32666395

RESUMO

BACKGROUND: The novel coronavirus disease 2019 (COVID-19) is an emerging worldwide threat to public health. While chest computed tomography (CT) plays an indispensable role in its diagnosis, the quantification and localization of lesions cannot be accurately assessed manually. We employed deep learning-based software to aid in detection, localization and quantification of COVID-19 pneumonia. METHODS: A total of 2460 RT-PCR tested SARS-CoV-2-positive patients (1250 men and 1210 women; mean age, 57.7 ± 14.0 years (age range, 11-93 years) were retrospectively identified from Huoshenshan Hospital in Wuhan from February 11 to March 16, 2020. Basic clinical characteristics were reviewed. The uAI Intelligent Assistant Analysis System was used to assess the CT scans. RESULTS: CT scans of 2215 patients (90%) showed multiple lesions of which 36 (1%) and 50 patients (2%) had left and right lung infections, respectively (> 50% of each affected lung's volume), while 27 (1%) had total lung infection (> 50% of the total volume of both lungs). Overall, 298 (12%), 778 (32%) and 1300 (53%) patients exhibited pure ground glass opacities (GGOs), GGOs with sub-solid lesions and GGOs with both sub-solid and solid lesions, respectively. Moreover, 2305 (94%) and 71 (3%) patients presented primarily with GGOs and sub-solid lesions, respectively. Elderly patients (≥ 60 years) were more likely to exhibit sub-solid lesions. The generalized linear mixed model showed that the dorsal segment of the right lower lobe was the favoured site of COVID-19 pneumonia. CONCLUSION: Chest CT combined with analysis by the uAI Intelligent Assistant Analysis System can accurately evaluate pneumonia in COVID-19 patients.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Aprendizado Profundo , Pulmão/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Pandemias , Pneumonia Viral/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/isolamento & purificação , COVID-19 , Teste para COVID-19 , Criança , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2 , Software , Adulto Jovem
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