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1.
J Clin Ultrasound ; 51(7): 1273-1275, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37219372

RESUMO

Superficial angiomyxoma in the scrotum is a well-circumscribed, ovoid-shaped, heterogeneously echogenic mass in the ultrasonography. On Doppler ultrasonography, vascular flow signals are visible in and around the mass(M).


Assuntos
Mixoma , Escroto , Masculino , Humanos , Escroto/diagnóstico por imagem , Ultrassom , Ultrassonografia , Mixoma/diagnóstico por imagem , Mixoma/cirurgia , Angiografia
2.
Acta Radiol ; 60(5): 653-662, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30142996

RESUMO

BACKGROUND: Diffusion tensor imaging (DTI) provides information about water molecule diffusion in spinal cord. PURPOSE: This study was aimed to investigate DTI changes in the different stages of compressive spinal cord induced by water-absorbing material implantation. MATERIAL AND METHODS: The spinal cord compression was administered over the fourth cervical vertebral level in rat. Rat models were divided into five subgroups according to compression stages: sham group, group A: three-day compression rat models; group B: 12-day compression rat models; group C: 20-day compression rat models; group D: 60-day compression rat models. DTI including fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in the compressive spinal cord were collected. The relationship between the Basso, Beattie, and Bresnahan (BBB) scores and DTI metrics was further explored. RESULTS: Compared with the sham group, BBB scoring of rat model showed a decreased tendency from group A ( P < 0.05) to group B ( P < 0.05). Then the motor function of rat model hindlimbs was recovered in some degree from group C ( P < 0.05) to group D ( P < 0.05) but had significant motor defects when compared with the normal level ( P < 0.05). The DTI metrics results revealed that chronic spinal cord compression resulted in lower FA value and higher ADC value at the compressive spinal cord level assessed at all four time-points ( P < 0.05). DTI metrics also showed a close correlation with motor function ( P < 0.05). CONCLUSION: DTI is an optimal pre-clinical imaging tool to reflect locomotor performance and pathological status of compressive spinal cord epicenter in chronic spinal cord compression rat model.


Assuntos
Imagem de Tensor de Difusão/métodos , Compressão da Medula Espinal/diagnóstico por imagem , Animais , Doença Crônica , Imagem de Difusão por Ressonância Magnética/métodos , Modelos Animais de Doenças , Ratos , Ratos Sprague-Dawley , Medula Espinal/diagnóstico por imagem , Tempo
3.
J Org Chem ; 82(19): 10051-10061, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28845663

RESUMO

A new and straightforward method for the synthesis of 5-bromotetracenes through PBr3-mediated cyclization of 1,7-diyn-3,6-bis(propargyl carbonate)s has been developed. This method offers several advantages such as easily accessible starting materials, high efficiency, and wide functional group compatibility. In addition, chloro- and iodo-substituted tetracenes were also synthesized using appropriate halogenating reagents. The utility of the 5-bromotetracene products has been illustrated by their efficient transformations through various palladium-catalyzed cross-coupling reactions.

4.
Chemistry ; 22(40): 14175-80, 2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27535212

RESUMO

Gold-catalyzed cyclization of various furan-ynes with a propargyl carbonate or ester moiety results in the formation of a series of polycyclic aromatic ring systems. The reactions can be rationalized through a tandem gold-catalyzed 3,3-rearrangement of the propargyl carboxylate moiety in furan-yne substrates to form an allenic intermediate, which is followed by an intramolecular Diels-Alder reaction of furan and subsequent ring-opening of the oxa-bridged cycloadduct. It was found that the steric and electronic properties of phosphine ligands on the gold catalyst had a significant impact on the reaction outcome. In the case of 1,5-furan-yne, the cleavage of the oxa-bridge in the cycloadduct with concomitant 1,2-migration of the R(1) group occurs to furnish anthracen-1(2H)-ones bearing a quaternary carbon center. For 1,4-furan-yne, a facile aromatization of the cycloadduct takes place to give 9-oxygenated anthracene derivatives.

5.
Chemistry ; 22(47): 16765-16769, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27643803

RESUMO

A Ni/BPh3 catalyzed [2+2+2] cycloaddition of alkyne-nitriles with alkynes has been developed, which provides an efficient route to fused pyridines under mild reaction conditions. Mechanistic studies indicate that an azanickelacycle via heterocoupling of an alkyne with a nitrile moiety is possibly formed as a key reaction intermediate. The Lewis acid catalyst is crucial to the successful transformation, which is suggested to promote the oxidative cyclization process.

6.
Chemistry ; 21(51): 18699-705, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26558737

RESUMO

The cyano-Schmittel cyclization of in situ-generated cyano-allenes has been carried out. The DFT calculation results suggest that the diradical pathway plays a major role in this cyclization. The reactions can be conveniently performed in a one-pot manner through cascade Sonogashira coupling of terminal cyano-ynes with organic halides, followed by base-promoted propargyl-allenyl isomerization/cyclization, leading to an efficient access to pyridine-fused polycyclic architectures. In particular, a large variety of aryl or heteroaryl rings such as furans, thiophenes and pyridines can be incorporated into the follow-up cyano-Diels-Alder reactions, highlighting the great synthetic utility of this chemistry.

7.
Chemistry ; 21(4): 1420-4, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25470360

RESUMO

Zirconocene-mediated multicomponent reactions of 1,3-butadiynes with ylidenemalononitriles in the absence or presence of CuCl have been developed. In the absence of CuCl, 1,3-butadiyne couples with three molecules of ylidenemalononitriles to yield azazirconacycles bearing a hexahydro-1,8-naphthyridine skeleton with high stereoselectivity. In the presence of CuCl, cyclopenta[b]pyridine or cyclopenta[b]quinolin-1-one derivatives are obtained via transmetalation of Zr-C bond to Cu-C bond as the key reaction step. These domino-type reactions proceed with high chemo-, regio- and/or stereoselectivities, and allowing the formation of multiple C-N and C-C bonds in a single operation.

8.
Chemistry ; 20(38): 12015-9, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25080016

RESUMO

Gold-catalyzed cascade cyclization/1,2-rearrangement of 1-(2-furanyl)phenyl propargyl alcohols has been developed, which provides a rapid and efficient access to multisubstituted 1-naphthols bearing an enal or enone moiety with high stereoselectivity. The (Z)- or (E)-stereochemistry can be easily controlled by choosing protected- or non-protected substrates. The utility of the methodology has been illustrated in the first total synthesis of wailupemycin G.


Assuntos
Ouro/química , Naftóis/química , Pironas/química , Pironas/síntese química , Catálise , Ciclização , Estrutura Molecular , Estereoisomerismo
9.
ACS Nano ; 18(22): 14085-14122, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38775446

RESUMO

Infectious diseases pose a serious threat and a substantial economic burden on global human and public health security, especially with the frequent emergence of multidrug-resistant (MDR) bacteria in clinical settings. In response to this urgent need, various photobased anti-infectious therapies have been reported lately. This Review explores and discusses several photochemical targeted antibacterial therapeutic strategies for addressing bacterial infections regardless of their antibiotic susceptibility. In contrast to conventional photobased therapies, these approaches facilitate precise targeting of pathogenic bacteria and/or infectious microenvironments, effectively minimizing toxicity to mammalian cells and surrounding healthy tissues. The highlighted therapies include photodynamic therapy, photocatalytic therapy, photothermal therapy, endogenous pigments-based photobleaching therapy, and polyphenols-based photo-oxidation therapy. This comprehensive exploration aims to offer updated information to facilitate the development of effective, convenient, safe, and alternative strategies to counter the growing threat of MDR bacteria in the future.


Assuntos
Antibacterianos , Infecções Bacterianas , Farmacorresistência Bacteriana Múltipla , Fotoquimioterapia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Animais , Bactérias/efeitos dos fármacos
10.
Front Endocrinol (Lausanne) ; 15: 1429115, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933823

RESUMO

Objectives: The growing incidence of differentiated thyroid cancer (DTC) have been linked to insulin resistance and metabolic syndrome. The imperative need for developing effective diagnostic imaging tools to predict the non-iodine-avid status of lung metastasis (LMs) in differentiated thyroid cancer (DTC) patients is underscored to prevent unnecessary radioactive iodine treatment (RAI). Methods: Primary cohort consisted 1962 pretreated LMs of 496 consecutive DTC patients with pretreated initially diagnosed LMs who underwent chest CT and subsequent post-treatment radioiodine SPECT. After automatic lesion segmentation by SE V-Net, SE Net deep learning was trained to predict non-iodine-avid status of LMs. External validation cohort contained 123 pretreated LMs of 24 consecutive patients from other two hospitals. Stepwise validation was further performed according to the nodule's largest diameter. Results: The SE-Net deep learning network yielded area under the receiver operating characteristic curve (AUC) values of 0.879 (95% confidence interval: 0.852-0.906) and 0.713 (95% confidence interval: 0.613-0.813) for internal and external validation. With the LM diameter decreasing from ≥10mm to ≤4mm, the AUCs remained relatively stable, for smallest nodules (≤4mm), the model yielded an AUC of 0.783. Decision curve analysis showed that most patients benefited using deep learning to decide radioactive I131 treatment. Conclusion: This study presents a noninvasive, less radioactive and fully automatic approach that can facilitate suitable DTC patient selection for RAI therapy of LMs. Further prospective multicenter studies with larger study cohorts and related metabolic factors should address the possibility of comprehensive clinical transformation.


Assuntos
Radioisótopos do Iodo , Neoplasias Pulmonares , Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Radioisótopos do Iodo/uso terapêutico , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Aprendizado Profundo , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Estudos de Coortes
11.
J Vis Exp ; (201)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38009754

RESUMO

Osteocytes are considered to be nonproliferative cells that are terminally differentiated from osteoblasts. Osteoblasts embedded in the bone extracellular matrix (osteoid) express the Pdpn gene to form cellular dendrites and transform into preosteocytes. Later, preosteocytes express the Dmp1 gene to promote matrix mineralization and thereby transform into mature osteocytes.This process is called osteocytogenesis. IDG-SW3 is a well-known cell line for in vitro studies of osteocytogenesis. Many previous methods have used collagen I as the main or the only component of the culturing matrix. However, in addition to collagen I, the osteoid also contains a ground substance, which is an important component in promoting cellular growth, adhesion, and migration. In addition, the matrix substance is transparent, which increases the transparency of the collagen I-formed gel and, thus, aids the exploration of dendrite formation through imaging techniques. Thus, this paper details a protocol to establish a 3D gel using an extracellular matrix along with collagen I for IDG-SW3 survival. In this work, dendrite formation and gene expression were analyzed during osteocytogenesis. After 7 days of osteogenic culture, an extensive dendrite network was clearly observed under a fluorescence confocal microscope. Real-time PCR showed that the mRNA levels of Pdpn and Dmp1 continually increased for 3 weeks. At week 4, the stereomicroscope revealed an opaque gel filled with mineral particles, consistent with the X-ray fluorescence (XRF) assay. These results indicate that this culture matrix successfully facilitates the transition from osteoblasts to mature osteocytes.


Assuntos
Matriz Extracelular , Osteoblastos , Matriz Extracelular/metabolismo , Osteócitos , Diferenciação Celular , Colágeno Tipo I/metabolismo , Técnicas de Cultura de Células
12.
Front Oncol ; 13: 1169616, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37256170

RESUMO

Background: Rectal cancer has a high risk of recurrence and metastasis, with median survival ranging from 24 months to 36 months. K-RAS mutation is a predictor of poor prognosis in rectal cancer. Advanced rectal cancer can be stopped in its tracks by pelvic exenteration. Case summary: A 51-year-old woman was diagnosed with advanced rectal cancer (pT4bN2aM1b, stage IV) with the KRAS G12D mutation due to a change in bowel habits. The patient had experienced repeated recurrences of rectal cancer after initial radical resection, and the tumor had invaded the ovaries, sacrum, bladder, vagina and anus. Since the onset of the disease, the patient had undergone a total of seven surgeries and long-term FOLFIRI- or XELOX-based chemotherapy regimens, with the targeted agents bevacizumab and regorafenib. Fortunately, the patient was able to achieve intraoperative R0 resection in almost all surgical procedures and achieve tumor-free survival after pelvic exenteration. The patient has been alive for 86 months since her diagnosis. Conclusions: Patients with advanced rectal cancer can achieve long-term survival through active multidisciplinary management and R0 surgery.

13.
Curr Pharm Biotechnol ; 24(14): 1795-1802, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36999704

RESUMO

INTRODUCTION: Alterations in red blood cell deformability (RBC-df) provide important information for the diagnosis of various diseases. AIM: We evaluated individual differences of lipopolysaccharide (LPS)-induced oxidative damage of RBC-df and analyzed the correlation between RBC-df and biochemical parameters. METHODS: A microfluidic chip was developed to detect inter-individual variability of different concentrations of LPS-induced oxidative damage of RBC-df in 9 healthy volunteers. The relationships between various biochemical indicators (Na+-K+-ATPase activity, lipid peroxide (LPO) content, glutathione peroxidase (GSH-PX) activity, catalase (CAT) activity, superoxide dismutase (SOD) activity, adenosine triphosphate (ATP) content, and hemoglobin (HB) content) and RBCsdf were investigated. RESULTS: The obvious inter-individual variability of LPS-induced oxidative damage of RBC-df was revealed. The Na+-K+-ATPase activity, LPO content, GSH-PX activity, and CAT activity of RBCs showed significant correlations with RBC-df (P < 0.05). CONCLUSION: Oxidative damage and energy metabolism are the critical factors of RBC-df impairment induced by LPS, and the individual dependence on RBC-df is an important indicator for the treatment of infection-associated sepsis since antibiotics can kill pathogenic bacteria, which results in the release of LPS from the cell wall.


Assuntos
Lipopolissacarídeos , Microfluídica , Eritrócitos , Antioxidantes/metabolismo , Peróxidos Lipídicos/metabolismo , Adenosina Trifosfatases/metabolismo
14.
Bone Joint Res ; 12(1): 33-45, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36642417

RESUMO

AIMS: Circular RNA (circRNA) is involved in the regulation of articular cartilage degeneration induced by inflammatory factors or oxidative stress. In a previous study, we found that the expression of circStrn3 was significantly reduced in chondrocytes of osteoarthritis (OA) patients and OA mice. Therefore, the aim of this paper was to explore the role and mechanism of circStrn3 in osteoarthritis. METHODS: Minus RNA sequencing, fluorescence in situ hybridization, and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the expression of circStrn3 in human and mouse OA cartilage tissues and chondrocytes. Chondrocytes were then stimulated to secrete exosomal miR-9-5p by cyclic tensile strain. Intra-articular injection of exosomal miR-9-5p into the model induced by destabilized medial meniscus (DMM) surgery was conducted to alleviate OA progression. RESULTS: Tensile strain could decrease the expression of circStrn3 in chondrocytes. CircStrn3 expression was significantly decreased in human and mouse OA cartilage tissues and chondrocytes. CircStrn3 could inhibit matrix metabolism of chondrocytes through competitively 'sponging' miRNA-9-5p targeting Kruppel-like factor 5 (KLF5), indicating that the decrease in circStrn3 might be a protective factor in mechanical instability-induced OA. The tensile strain stimulated chondrocytes to secrete exosomal miR-9-5p. Exosomes with high miR-9-5p expression from chondrocytes could inhibit osteoblast differentiation by targeting KLF5. Intra-articular injection of exosomal miR-9-5p alleviated the progression of OA induced by destabilized medial meniscus surgery in mice. CONCLUSION: Taken together, these results demonstrate that reduction of circStrn3 causes an increase in miR-9-5p, which acts as a protective factor in mechanical instability-induced OA, and provides a novel mechanism of communication among joint components and a potential application for the treatment of OA.Cite this article: Bone Joint Res 2023;12(1):33-45.

15.
Sci Adv ; 9(24): eadf0988, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37315130

RESUMO

Osteoarthritis (OA) is the most common degenerative joint disease in the world. Gene therapy based on delivering microRNAs (miRNAs) into cells has potential for the treatment of OA. However, the effects of miRNAs are limited by the poor cellular uptake and stability. Here, we first identify a type of microRNA-224-5p (miR-224-5p) from clinical samples of patients with OA that can protect articular cartilage from degeneration and further synthesize urchin-like ceria nanoparticles (NPs) that can load miR-224-5p for enhanced gene therapy of OA. Compared with traditional sphere ceria NPs, the thorns of urchin-like ceria NPs can efficiently promote the transfection of miR-224-5p. In addition, urchin-like ceria NPs have excellent performance of scavenging reactive oxygen species (ROS), which can regulate the microenvironment of OA to further improve the gene treatment of OA. The combination of urchin-like ceria NPs and miR-224-5p not only exhibits favorable curative effect for OA but also provides a promising paradigm for translational medicine.


Assuntos
MicroRNAs , Nanopartículas , Osteoartrite , Humanos , MicroRNAs/genética , Transporte Biológico , Terapia Genética , Osteoartrite/genética , Osteoartrite/terapia
16.
Adv Sci (Weinh) ; 10(33): e2303015, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37857552

RESUMO

Postmenopausal osteoporosis (PMO) is often accompanied by neuroendocrine changes in the hypothalamus, which closely associates with the microbial diversity, community composition, and intestinal metabolites of gut microbiota (GM). With the emerging role of GM in bone metabolism, a potential neuroendocrine signal neuropeptide Y (NPY) mediated brain-gut-bone axis has come to light. Herein, it is reported that exogenous overexpression of NPY reduced bone formation, damaged bone microstructure, and up-regulated the expressions of pyroptosis-related proteins in subchondral cancellous bone in ovariectomized (OVX) rats, but Y1 receptor antagonist (Y1Ra) reversed these changes. In addition, it is found that exogenous overexpression of NPY aggravated colonic inflammation, impaired intestinal barrier integrity, enhanced intestinal permeability, and increased serum lipopolysaccharide (LPS) in OVX rats, and Y1Ra also reversed these changes. Most importantly, NPY and Y1Ra modulated the microbial diversity and changed the community composition of GM in OVX rats, and thereby affecting the metabolites of GM (e.g., LPS) entering the blood circulation. Moreover, fecal microbiota transplantation further testified the effect of NPY-mediated GM changes on bone. In vitro, LPS induced pyroptosis, reduced viability, and inhibited differentiation of osteoblasts. The study demonstrated the existence of NPY-mediated brain-gut-bone axis and it might be a novel emerging target to treat PMO.


Assuntos
Microbioma Gastrointestinal , Osteoporose Pós-Menopausa , Feminino , Humanos , Ratos , Animais , Neuropeptídeo Y/metabolismo , Lipopolissacarídeos , Hipotálamo/metabolismo
17.
Acta Biomater ; 167: 401-415, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37330028

RESUMO

MicroRNAs play a crucial role in regulating cartilage extracellular matrix (ECM) metabolism and are being explored as potential therapeutic targets for osteoarthritis (OA). The present study indicated that microRNA-224-5p (miR-224-5p) could balance the homeostasis of OA via regulating cartilage degradation and synovium inflammatory simultaneously. Multifunctional polyamidoamine dendrimer with amino acids used as efficient vector to deliver miR-224-5p. The vector could condense miR-224-5p into transfected nanoparticles, which showed higher cellular uptake and transfection efficiency compared to lipofectamine 3000, and also protected miR-224-5p from RNase degradation. After treatment with the nanoparticles, the chondrocytes showed an increase in autophagy rate and ECM anabolic components, as evidenced by the upregulation of autophagy-related proteins and OA-related anabolic mediators. This led to a corresponding inhibition of cell apoptosis and ECM catabolic proteases, ultimately resulting in the alleviation of ECM degradation. In addition, miR-224-5p also inhibited human umbilical vein endothelial cells angiogenesis and fibroblast-like synoviocytes inflammatory hyperplasia. Integrating the above synergistic effects of miR-224-5p in regulating homeostasis, intra-articular injection of nanoparticles performed outstanding therapeutic effect by reducing articular space width narrowing, osteophyte formation, subchondral bone sclerosis and inhibiting synovial hypertrophy and proliferation in the established mouse OA model. The present study provides a new therapy target and an efficient intra-articular delivery method for improving OA therapy. STATEMENT OF SIGNIFICANCE: Osteoarthritis (OA) is the most prevalent joint disease worldwide. Gene therapy, which involves delivering microRNAs, has the potential to treat OA. In this study, we demonstrated that miR-224-5p can simultaneously regulate cartilage degradation and synovium inflammation, thereby restoring homeostasis in OA gene therapy. Moreover, compared to traditional transfection reagents such as lipofectamine 3000, G5-AHP showed better efficacy in both microRNA transfection and protection against degradation due to its specific surface structure. In summary, G5-AHP/miR-224-5p was developed to meet the clinical needs of OA patients and the high requirement of gene transfection efficiency, providing a promising paradigm for the future application and development of gene therapy.


Assuntos
Cartilagem Articular , MicroRNAs , Osteoartrite , Camundongos , Animais , Humanos , Células Endoteliais/metabolismo , MicroRNAs/farmacologia , Cartilagem/metabolismo , Condrócitos/metabolismo , Osteoartrite/tratamento farmacológico , Inflamação/metabolismo , Homeostase , Modelos Animais de Doenças , Apoptose , Cartilagem Articular/metabolismo
18.
J Psychol ; 146(5): 485-509, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22931006

RESUMO

Few studies have provided the validity evidence of a measure of objective person-organization fit (P-O fit) as a selection tool. The present study used a concurrent validation design to examine the criterion-related validity and the incremental validity of a P-O fit measure beyond the validity of the Big Five personality test for predicting job performance (task performance and organizational citizenship behavior) and employee commitment (organizational commitment and supervisory commitment) for a group of high-tech professional employees in Taiwan. Results showed that P-O fit predicted the contextual component of overall job performance and was significantly related to two types of employee commitment. Moreover, P-O fit had an incremental validity beyond that of the personality measures for predicting some of our outcome variables.


Assuntos
Avaliação de Desempenho Profissional , Emprego/psicologia , Cultura Organizacional , Testes de Personalidade/normas , Seleção de Pessoal/normas , Psicometria/métodos , Adulto , Humanos , Objetivos Organizacionais , Psicologia Industrial , Psicometria/normas , Reprodutibilidade dos Testes
19.
Anal Chim Acta ; 1221: 340131, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35934366

RESUMO

Elevated C-reactive protein (CRP) levels are linked with bacterial infection, local inflammation in osteoarthritis and the increased risk of developing cardiovascular disease. Here, a sensitive and label-free CRP assay is developed by combining cyclic enzymatic signal amplification and capillary electrophoresis (CE) with UV detection. This assay is constructed of base pairing and target recognition. Thereinto, nicking endonuclease (NEase) can recognize the specific nucleotide sequences in double-stranded DNA (dsDNA), which is formed by a CRP aptamer and its complementary DNA (cDNA). Sequentially, NEase cleaves only cDNA to produce signal DNAs. Therefore, a large number of signal DNAs are generated through continuous enzyme cleavage. In the presence of CRP, the aptamer recognizes and binds to CRP with high affinity and selectivity, which results in a decrease in signal DNAs, and thus the UV absorption value of CE significantly decreases, too. A wide linear range was obtained between 0.0125 and 15 µg mL-1 (0.11-130.5 nM) in 1% human serum with a detection limit of 4 ng mL-1 (35 pM). Additionally, the proposed method is universal and can be applied to analyze other similar substances by altering the matched aptamer.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/genética , Técnicas Biossensoriais/métodos , DNA/análise , DNA Complementar , Eletroforese Capilar , Endonucleases , Humanos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico
20.
J Pharm Anal ; 12(5): 808-813, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36320608

RESUMO

The identification of tumor-related microRNAs (miRNAs) exhibits excellent promise for the early diagnosis of cancer and other bioanalytical applications. Therefore, we developed a sensitive and efficient biosensor using polyadenine (polyA)-mediated fluorescent spherical nucleic acid (FSNA) for miRNA analysis based on strand displacement reactions on gold nanoparticle (AuNP) surfaces and electrokinetic signal amplification (ESA) on a microfluidic chip. In this FSNA, polyA-DNA biosensor was anchored on AuNP surfaces via intrinsic affinity between adenine and Au. The upright conformational polyA-DNA recognition block hybridized with 6-carboxyfluorescein-labeled reporter-DNA, resulting in fluorescence quenching of FSNA probes induced by AuNP-based resonance energy transfer. Reporter DNA was replaced in the presence of target miRNA, leading to the recovery of reporter-DNA fluorescence. Subsequently, reporter-DNAs were accumulated and detected in the front of with Nafion membrane in the microchannel by ESA. Our method showed high selectivity and sensitivity with a limit of detection of 1.3 pM. This method could also be used to detect miRNA-21 in human serum and urine samples, with recoveries of 104.0%-113.3% and 104.9%-108.0%, respectively. Furthermore, we constructed a chip with three parallel channels for the simultaneous detection of multiple tumor-related miRNAs (miRNA-21, miRNA-141, and miRNA-375), which increased the detection efficiency. Our universal method can be applied to other DNA/RNA analyses by altering recognition sequences.

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