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1.
Mikrochim Acta ; 191(8): 464, 2024 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007936

RESUMO

Rapid and high-sensitive Salmonella detection in milk is important for preventing foodborne disease eruption. To overcome the influence of the complex ingredients in milk on the sensitive detection of Salmonella, a dual-signal reporter red fluorescence nanosphere (RNs)-Pt was designed by combining RNs and Pt nanoparticles. After being equipped with antibodies, the immune RNs-Pt (IRNs-Pt) provide an ultra-strong fluorescence signal when excited by UV light. With the assistance of the H2O2/TMB system, a visible color change appeared that was attributed to the strong peroxidase-like catalytic activity derived from Pt nanoparticles. The IRNs-Pt in conjunction with immune magnetic beads can realize that Salmonella typhimurium (S. typhi) was captured, labeled, and separated effectively from untreated reduced-fat pure milk samples. Under the optimal experimental conditions, with the assay, as low as 50 CFU S. typhi can be converted to detectable fluorescence and absorbance signals within 2 h, suggesting the feasibility of practical application of the assay. Meanwhile, dual-signal modes of quantitative detection were realized. For fluorescence signal detection (emission at 615 nm), the linear correlation between signal intensity and the concentration of S. typhi was Y = 83C-3321 (R2 = 0.9941), ranging from 103 to 105 CFU/mL, while for colorimetric detection (absorbamce at 450 nm), the relationship between signal intensity and the concentration of S. typhi was Y = 2.9logC-10.2 (R2 = 0.9875), ranging from 5 × 103 to 105 CFU/mL. For suspect food contamination by foodborne pathogens, this dual-mode signal readout assay is promising for achieving the aim of convenient preliminary screening and accurate quantification simultaneously.


Assuntos
Colorimetria , Leite , Salmonella typhimurium , Leite/microbiologia , Leite/química , Salmonella typhimurium/isolamento & purificação , Colorimetria/métodos , Animais , Nanopartículas Metálicas/química , Limite de Detecção , Platina/química , Peróxido de Hidrogênio/química , Fluorescência , Nanosferas/química , Microbiologia de Alimentos/métodos , Contaminação de Alimentos/análise , Espectrometria de Fluorescência/métodos
2.
Nanoscale ; 16(7): 3631-3640, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38276969

RESUMO

Circulating tumor cells in human peripheral blood play an important role in cancer metastasis. In addition to the size-based and antibody-based capture and separation of cancer cells, their electrical characterization is important for rare cell detection, which can prove fatal in point-of-care testing. Herein, an organic electrochemical transistor (OECT) biosensor made of solution-gated carboxyl graphene mixed with PEDOT:PSS for the detection of cancer cells in situ is reported. Carboxyl graphene was used in this work to modulate cancer cell morphology, which differs significantly from normal blood cells, to achieve rare cancer cell detection. When the concentration of carboxyl graphene mixed in PEDOT:PSS was increased from 0 to 5 mg mL-1, the cancer cell surface area increased from 218 µm2 to 530 µm2, respectively. A change in cell morphology was also detected by the OECT. Negative charges in the cancer cells induced a positive shift in gate voltage, which was approximately 40 mV for spherical-shaped cells. When the cell surface area increased, transfer curves of transistor revealed a negative shift in gate voltage. Therefore, the sensor can be used for in situ detection of cancer cell morphology during the cell capture process, which can be used to identify whether the captured cells are deformable.


Assuntos
Técnicas Biossensoriais , Grafite , Células Neoplásicas Circulantes , Humanos , Grafite/química , Técnicas Eletroquímicas , Membrana Celular
3.
J Environ Manage ; 351: 119846, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128205

RESUMO

The design of urban drainage infrastructure is mainly based on historical conditions. Under global warming, more intense precipitation extremes will pose severe risk to current infrastructure. The evaluation of where and by how much design standards need to change, is urgently needed to help maintain well-functioning drainage systems. In this study, we used climate projections from the Coupled Model Intercomparison Project Phase 6 (CMIP6) and InfoWorks Integrated Catchment Modeling (ICM) to simulate urban flooding. According to the latest design standard of urban drainage infrastructure, we assess the risk of future urban flooding, and evaluate the effect and benefit of drainage infrastructure adaptation measures. The results showed that, under the shared socioeconomic pathway (SSP) 5-8.5 scenario, a 35% increase in extreme rainfall would be expected. Under a 1-in-30-year precipitation event, the maximum depth would increase by 5.59%, and the withdrawal time would rise by 2.94% in the future period, relative to the baseline level. After the enlargement of drainage infrastructure in local areas, 10% pipe enlargement has a better effect to reduce risk and higher benefits than 5% pipe enlargement. These findings provide valuable insights for policymakers in enhancing the drainage system and adapting to climate change.


Assuntos
Drenagem Sanitária , Modelos Teóricos , Drenagem Sanitária/métodos , Cidades , Inundações , China
4.
Cerebrovasc Dis ; 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38128486

RESUMO

Introduction Acute small subcortical infarctions (SSIs) result from occlusions of small penetrating arteries, and the underlying pathological factors can have different clinical implications. The objective of this study was to assess the clinical relevance of acute SSIs based on their sizes and morphologies. Methods This retrospective case-control study analyzed clinical and imaging data of stroke patients with acute SSIs in penetrating artery territories who underwent MRI within 5 days of stroke onset, registered between 2016 and 2020. We categorized these patients into three groups based on size and morphology: diameter < 20mm, diameter ≧ 20mm, and separated lesions. We then evaluated their clinical characteristics and outcomes. Results We analyzed 726 stroke patients with SSIs, among whom 573 had a diameter <20mm, 99 had a diameter ≥20mm, and 54 had separated lesions. The patients had a median age of 70 years and a median National Institutes of Health Stroke Scale (NIHSS) score of 4 on arrival. Patients who experienced early neurological deterioration (END) had a significantly lower chance of good functional outcomes (27.3% vs. 64.4%, p<0.001). Patients with a diameter ≧20mm had the most severe NIHSS on arrival and at day 3, the highest rate of END, and the lowest rate of good outcome at 3 months. The incidence of cardioembolism did not differ between patients with diameters of ≥20mm and <20mm. However, multiple logistic regression analysis revealed that separated lesions were more likely to be associated with cardioembolic stroke (adjusted odds ratio [aOR], 7.6; 95% confidence interval [CI], 2.0-28.5) and parent artery stenosis >50% (aOR, 3.8; 95% CI, 2.1-7.0) than a diameter of <20mm. Moreover, SSIs with a diameter of ≥20mm was found to be associated with an increased risk of END compared to that with a diameter of <20mm (aOR, 2.9; 95% CI, 1.7-5.2). Conclusion Our study suggests that the sizes and morphologies of acute SSIs may indicate different underlying pathologies and be linked to diverse clinical outcomes. Our findings also challenge the current imaging criteria for embolic stroke of undetermined source, as we did not find a link between large subcortical infarction and cardioembolic stroke.

5.
RSC Adv ; 13(51): 36416-36423, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38099254

RESUMO

Organic electrochemical transistor (OECT) was applied in chemical and biological sensing. In this work, we developed a simple and repeatable method to fabricate OECT array, which had been successfully used to detect cancer cells. PEDPT:PSS conductive film between source and drain electrodes were patterned through photolithography, which can achieve uniform devices with same electrical characterization. When MCF-7 cancer cells are captured on the PEDOT:PSS surface via specifical antibody, the transfer characteristic of OECT shifts to higher gate electrode voltage due to the electrostatic interaction between cancer cells and device. The effective gate voltage shift can reach about 63 mV when the concentration of cancer cells increased to 5000. The shift of effective gate voltage is related to the cancer cell morphology, which is increased in the first 1 h and decreased when the capture time was larger than 1 h. The device of OECT array can increase the sample flux and make the detection result more accurate. It is expected that OECT array will have promising practical applications in single cancer cell detection in the future.

7.
Talanta ; 263: 124700, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37247452

RESUMO

Immunosorbent assay is one of the most popular immunological screening techniques which has been widely used for the clinical diagnosis of alpha-fetoprotein (AFP). While traditional immunosorbent assay (ELISA) suffers from low detection sensitivity due to its low intensity of colorimetric signal. To improve the sensitivity of AFP detection, we developed a new and sensitive immunocolorimetric biosensor by combining Ps-Pt nanozyme with terminal deoxynucleotidyl transferase (TdT)-mediated polymerization reaction. The determination of AFP was achieved by measuring the visual color intensity produced by the catalytic oxidation reaction of the 3,3',5,5'-tetramethylbenzidine (TMB) solution with Ps-Pt and horseradish peroxidase (HRP). Owing to the synergistic catalysis of Ps-Pt and horseradish peroxidase HRP enriched in polymerized amplification products, this biosensor exhibited a significant color change within 25 s in the presence of 10-500 pg/mL AFP. This proposed method allowed for the specific detection of AFP with a detection limit of 4.30 pg/mL and even 10 pg/mL target protein could be distinguished clearly by visual observation. Furthermore, this biosensor could be applied to analysis of AFP in the complex sample and could be easily extended to the detection of other proteins.


Assuntos
Técnicas Biossensoriais , alfa-Fetoproteínas , alfa-Fetoproteínas/análise , Colorimetria/métodos , Imunoadsorventes , Peroxidase do Rábano Silvestre/metabolismo , Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio , Limite de Detecção
8.
Materials (Basel) ; 16(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37109900

RESUMO

A 3D network capture substrate based on poly(lactic-co-glycolic acid) (PLGA) nanofibers was studied and successfully used for high-efficiency cancer cell capture. The arc-shaped glass micropillars were prepared by chemical wet etching and soft lithography. PLGA nanofibers were coupled with micropillars by electrospinning. Given the size effect of the microcolumn and PLGA nanofibers, a three-dimensional of micro-nanometer spatial network was prepared to form a network cell trapping substrate. After the modification of a specific anti-EpCAM antibody, MCF-7 cancer cells were captured successfully with a capture efficiency of 91%. Compared with the substrate composed of 2D nanofibers or nanoparticles, the developed 3D structure based on microcolumns and nanofibers had a greater contact probability between cells and the capture substrate, leading to a high capture efficiency. Cell capture based on this method can provide technical support for rare cells in peripheral blood detection, such as circulating tumor cells and circulating fetal nucleated red cells.

9.
Ecotoxicol Environ Saf ; 254: 114736, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36905847

RESUMO

Tetrabromobisphenol A (TBBPA), Tetrachlorobisphenol A (TCBPA), Tetrabromobisphenol S (TBBPS) and their derivatives as the most widely used halogenated flame retardants (HFR), had been employed in the manufacturing industry to raise fire safety. HFRs have been shown to be developmentally toxic to animals and also affect plant growth. However, little was known about the molecular mechanism responded by when plants were treated with these compounds. In this study, when Arabidopsis was exposed to four HFRs (TBBPA, TCBPA, TBBPS-MDHP, TBBPS), the stress of these compounds had different inhibitory effects on seed germination and plant growth. Transcriptome and metabolome analysis showed that all four HFRs could influence the expression of transmembrane transporters to affect ion transport, Phenylpropanoid biosynthesis, Plant-pathogen interaction, MAPK signalling pathway and other pathways. In addition, the effects of different kinds of HFR on plants also have variant characteristics. It is very fascinating that Arabidopsis shows the response of biotic stress after exposure to these kinds of compounds, including the immune mechanism. Overall, the findings of the mechanism recovered by methods of transcriptome and metabolome analysis supplied a vital insight into the molecular perspective for Arabidopsis response to HFRs stress.


Assuntos
Arabidopsis , Retardadores de Chama , Bifenil Polibromatos , Animais , Transcriptoma , Arabidopsis/genética , Retardadores de Chama/toxicidade
10.
Mol Biotechnol ; 65(4): 655-667, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36214976

RESUMO

LINC00467 was reported as an oncogenic gene in different types of human cancers. In this study, we investigated the molecular mechanisms of LINC00467 in the tumorigenesis of laryngeal squamous cell cancer (LSCC). RT-qPCR was utilized to detect the mRNA expression of genes, and western blot assay was used to determine the protein levels of TNF alpha-induced protein 3 (TNFAIP3). The cell viability was detected by CCK-8 assay. Transwell assays were conducted to determine the cell migration and invasion of LSCC cells, and the cell cycle was assessed by flow cytometry. The association between paired box 5 (PAX5), LINC00467, miR-4735-3p, and TNFAIP3 was verified using ChIP, RNA pull-down, or luciferase reporter assays. In our study, we found that LINC00467 was upregulated in LSCC, and knockdown of LINC00467 suppressed cell viability and metastasis of LSCC. Besides, LINC00467 transcription could be activated by PAX5 in LSCC. Furthermore, LINC00467 acted as competitive endogenous RNA (ceRNA) for miR-4735-3p to accelerate LSCC progression. In the meantime, TNFAIP3 was identified as a downstream gene of miR-4735-3p. Finally, TNFAIP3 overexpression could overturn the effects of miR-4735-3p mimic on LSCC cellular activities. In conclusion, our results demonstrated that PAX5-induced LINC00467 facilitated LSCC progression by inhibiting miR-4735-3p to increase TNFAIP3 expression.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação para Cima , Fator de Necrose Tumoral alfa/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , Linhagem Celular Tumoral , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica
12.
Biochem Pharmacol ; 206: 115341, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36356658

RESUMO

Our studies demonstrated the critical role of Histone deacetylases (HDACs) in the regulation of nephrogenesis. To better understand the key pathways regulated by HDAC1/2 in early nephrogenesis, we performed chromatin immunoprecipitation sequencing (ChIP-Seq) of HDAC1/2 on isolated nephron progenitor cells (NPCs) from mouse E16.5 kidneys. Our analysis revealed that 11,802 (40.4%) of HDAC1 peaks overlap with HDAC2 peaks, further demonstrates the redundant role of HDAC1 and HDAC2 during nephrogenesis. Common HDAC1/2 peaks are densely concentrated close to the transcriptional start site (TSS). GREAT Gene Ontology analysis of overlapping HDAC1/2 peaks reveals that HDAC1/2 are associated with metanephric nephron morphogenesis, chromatin assembly or disassembly, as well as other DNA checkpoints. Pathway analysis shows that negative regulation of Wnt signaling pathway is one of HDAC1/2's most significant function in NPCs. Known motif analysis indicated that Hdac1 is enriched in motifs for Six2, Hox family, and Tcf family members, which are essential for self-renewal and differentiation of nephron progenitors. Interestingly, we found the enrichment of HDAC1/2 at the enhancer and promoter regions of actively transcribed genes, especially those concerned with NPC self-renewal. HDAC1/2 simultaneously activate or repress the expression of different genes to maintain the cellular state of nephron progenitors. We used the Integrative Genomics Viewer to visualize these target genes associated with each function and found that HDAC1/2 co-bound to the enhancers or/and promoters of genes associated with nephron morphogenesis, differentiation, and cell cycle control. Taken together, our ChIP-Seq analysis demonstrates that HDAC1/2 directly regulate the molecular cascades essential for nephrogenesis.


Assuntos
Redes Reguladoras de Genes , Néfrons , Animais , Camundongos , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Néfrons/metabolismo , Células-Tronco/fisiologia , Via de Sinalização Wnt
13.
Front Neurol ; 13: 952462, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36176550

RESUMO

Background and purpose: The early identification of cardioembolic stroke is critical for the early initiation of anticoagulant treatment. However, it can be challenging to identify the major cardiac source, particularly since the predominant source, paroxysmal atrial fibrillation (AF), may not be present at the time of stroke. In this study, we aimed to evaluate imaging predictors for unrecognized AF in patients with acute ischemic stroke. Methods: We performed a cross-sectional analysis of data and magnetic resonance imaging (MRI) scans from two prospective cohorts of patients who underwent serial 12-lead electrocardiography and 24-h Holter monitoring to detect unrecognized AF. The imaging patterns in diffusion-weighted imaging and imaging characteristics were assessed and classified. A logistic regression model was used to identify predictive factors for newly detected AF in patients with acute ischemic stroke. Results: A total of 734 patients were recruited for analysis, with a median age of 72 (interquartile range: 65-79) years and a median National Institutes of Health Stroke Scale score of 4 (interquartile range: 2-6). Of these patients, 64 (8.7%) had newly detected AF during the follow-up period. Stepwise multivariate logistic regression revealed that age ≥75 years [adjusted odds ratio (aOR) 5.66, 95% confidence interval (CI) 2.98-10.75], receiving recombinant tissue plasminogen activator treatment (aOR 4.36, 95% CI 1.65-11.54), congestive heart failure (aOR 6.73, 95% CI 1.85-24.48), early hemorrhage in MRI (aOR 3.62, 95% CI 1.52-8.61), single cortical infarct (aOR 6.49, 95% CI 2.35-17.92), and territorial infarcts (aOR 3.54, 95% CI 1.06-11.75) were associated with newly detected AF. The C-statistic of the prediction model for newly detected AF was 0.764. Conclusion: Initial MRI at the time of stroke may be useful to predict which patients have cardioembolic stroke caused by unrecognized AF. Further studies are warranted to verify these findings and their application to high-risk patients.

14.
J Am Soc Nephrol ; 33(7): 1308-1322, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35383123

RESUMO

BACKGROUND: We reasoned that unraveling the dynamic changes in accessibility of genomic regulatory elements and gene expression at single-cell resolution will inform the basic mechanisms of nephrogenesis. METHODS: We performed single-cell ATAC-seq and RNA-seq both individually (singleomes; Six2GFP cells) and jointly in the same cells (multiomes; kidneys) to generate integrated chromatin and transcriptional maps in mouse embryonic and neonatal nephron progenitor cells. RESULTS: We demonstrate that singleomes and multiomes are comparable in assigning most cell states, identification of new cell type markers, and defining the transcription factors driving cell identity. However, multiomes are more precise in defining the progenitor population. Multiomes identified a "pioneer" bHLH/Fox motif signature in nephron progenitor cells. Moreover, we identified a subset of Fox factors exhibiting high chromatin activity in podocytes. One of these Fox factors, Foxp1, is important for nephrogenesis. Key nephrogenic factors are distinguished by strong correlation between linked gene regulatory elements and gene expression. CONCLUSION: Mapping the regulatory landscape at single-cell resolution informs the regulatory hierarchy of nephrogenesis. Paired single-cell epigenomes and transcriptomes of nephron progenitors should provide a foundation to understand prenatal programming, regeneration after injury, and ex vivo nephrogenesis.


Assuntos
Cromatina , Podócitos , Animais , Diferenciação Celular/genética , Cromatina/metabolismo , Feminino , Proteínas de Homeodomínio/genética , Rim/metabolismo , Camundongos , Néfrons/metabolismo , Organogênese/genética , Podócitos/metabolismo , Gravidez , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
Anal Methods ; 13(47): 5694-5699, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34812810

RESUMO

MicroRNAs play important roles in disease diagnosis and therapy. However, current methods for microRNA detection suffer from low sensitivity and cannot directly detect short microRNAs. Herein, we have developed a highly sensitive and selective fluorescent method for direct microRNA detection by combining the duplex-specific nuclease-assisted recycling amplification and the nicking enzyme-powered three-dimensional DNA walker. Target microRNA initiates duplex-specific nuclease-assisted recycling amplification, releasing numerous bipedal walking strands. The released bipedal walking strands hybridize with carboxyfluorescein-labeled track DNA and form nicking recognition site. Driven by the hydrolysis of the nicking enzyme, the bipedal walking strand autonomously moves along the track strand, releasing a large number of carboxyfluorescein-labeled DNA fragments and generating obvious fluorescence signals. This dual-signal amplification method can directly detect microRNA 21 as low as 130 fM and has good selectivity. The proposed method is not only simple for nucleic acid design, but also can be used as a universal method for the highly sensitive detection of all RNAs.


Assuntos
MicroRNAs , Técnicas de Amplificação de Ácido Nucleico , DNA , Endonucleases , MicroRNAs/análise , MicroRNAs/biossíntese , MicroRNAs/química , Técnicas de Amplificação de Ácido Nucleico/métodos
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(8): 802-808, 2021 Aug 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34511169

RESUMO

OBJECTIVES: To study the association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphism with susceptibility to bronchial asthma and glucocorticoid (GC) efficacy in children. METHODS: A total of 173 children with bronchial asthma who were hospitalized between June 2018 and December 2020 were selected as the observation group. The children received aerosol inhalation of GC for three consecutive months. A total of 178 healthy children who underwent physical examination during the same period were selected as the control group. PCR was used to detect the genotypes of the MTHFR C677T for the two groups. The differences in genotype distribution between the two groups were analyzed. Children with different genotypes in the observation group were compared in terms of immunoglobulin E (IgE), interleukin-8 (IL-8), leukotriene B4 (LTB4), lung function, and clinical outcome before and after treatment. RESULTS: TT genotype and T allele were significantly more frequent in the observation group than in the control group (P<0.001). TT/CT genotypes and T allele were independent risk factors for bronchial asthma (OR=6.615 and 7.055 respectively; P<0.001). After GC treatment, the children with CC, CT or TT genotypes experienced significantly decreased levels of IgE, IL-8, and LTB4 and significantly increased forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio (P<0.001). The children with TT genotype showed significantly lower levels of IL-8 and LTB4 than those with CC genotype, a significantly lower level of LTB4 than those with CT genotype, significantly higher FVC than those with CT genotype, and a significantly higher FEV1/FVC ratio than those with CC genotype (P<0.05). The children with TT genotype had better GC efficacy compared with those with CC genotype (P<0.05). TT genotype was an independent factor for good GC efficacy (OR=2.111, P=0.018). CONCLUSIONS: MTHFR gene polymorphism is associated with asthma susceptibility and GC efficacy in children. Children carrying TT/CT genotypes have a higher risk of developing asthma, and those with TT genotype are more sensitive to GC treatment.


Assuntos
Asma , Glucocorticoides , Alelos , Asma/tratamento farmacológico , Asma/genética , Criança , Predisposição Genética para Doença , Genótipo , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético
17.
RSC Adv ; 11(60): 37917-37922, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-35498089

RESUMO

Highly sensitive detection of DNA is of great importance for the detection of genetic damage and errors for the diagnosis of many diseases. Traditional highly sensitive organic electrochemical transistor (OECT)-based methods mainly rely on good conductivity materials, which may be limited by complex synthesis and modification steps. In this work, DNA biosensor based on OECT and hybridization chain reaction (HCR) signal amplification was demonstrated for the first time. Au nanoparticles were electrochemically deposited on the Au gate electrode to increase the surface area. Then, the HCR products, long negatively charged double-stranded DNA, were connected to the target by hybridization, which can increase the effective gate voltage offset of OECT. This sensor exhibited high sensitivity and even 0.1 pM target DNA could be directly detected with a significant voltage shift. In addition, it could discriminate target DNA from the mismatched DNA with good selectivity. This proposed method based on HCR in DNA detection exhibited an efficient amplification performance on OECT, which provided new opportunities for highly sensitive and selective detection of DNA.

18.
Epigenetics ; 16(11): 1235-1250, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33315499

RESUMO

The epigenetic regulator Dot1, the only known histone H3K79 methyltransferase, has a conserved role in organismal development and homoeostasis. In yeast, Dot1 is required for telomeric silencing and genomic integrity. In Drosophila, Dot1 (Grappa) regulates homoeotic gene expression. Dysregulation of DOT1L (human homologue of Dot1) causes leukaemia and is implicated in dilated cardiomyopathy. In mice, germline disruption of Dot1L and loss of H3K79me2 disrupt vascular and haematopoietic development. Targeted inactivation of Dot1L in principal cells of the mature collecting duct affects terminal differentiation and cell type patterning. However, the role of H3K79 methylation in mammalian tissue development has been questioned, as it is dispensable in the intestinal epithelium, a rapidly proliferating tissue. Here, we used lineage-specific Cre recombinase to delineate the role of Dot1L methyltransferase activity in the mouse metanephric kidney, an organ that develops via interactions between ureteric epithelial (Hoxb7) and mesenchymal (Six2) cell lineages. The results demonstrate that Dot1LHoxb7 is dispensable for ureteric bud branching morphogenesis. In contrast, Dot1LSix2 is critical for the maintenance and differentiation of Six2+ progenitors into epithelial nephrons. Dot1LSix2 mutant kidneys exhibit congenital nephron deficit and cystic dysplastic kidney disease. Molecular analysis implicates defects in key renal developmental regulators, such as Lhx1, Pax2 and Notch. We conclude that the developmental functions of Dot1L-H3K79 methylation in the kidney are lineage-restricted. The link between H3K79me and renal developmental pathways reaffirms the importance of chromatin-based mechanisms in organogenesis.


Assuntos
Histonas , Lisina , Animais , Metilação de DNA , Histona Metiltransferases , Histona-Lisina N-Metiltransferase , Histonas/metabolismo , Lisina/metabolismo , Metiltransferases/genética , Camundongos , Néfrons/metabolismo
19.
Life Sci ; 262: 118506, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33031827

RESUMO

AIMS: Bortezomib (BTZ) is described as the first-line agent for multiple myeloma (MM) chemotherapy, but the emergence of BTZ resistance usually results in the failure of chemotherapy in MM. Circular RNA (circRNA) itchy E3 ubiquitin protein ligase (circITCH) is a novel identified circRNA that plays a vital role in the development of human cancers. However, the role of circITCH in the development of BTZ resistance in MM remains elusive. MATERIALS AND METHODS: The expression of circITCH, miR-615-3p, and protein kinase C, delta (PRKCD) was detected with quantitative reverse transcription PCR and western blot. The effects of circITCH on the sensitivity of MM cells to BTZ were assessed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, flow cytometry, and xenograft tumor assay. The interaction of circITCH, microRNA-615-3p, and PRKCD was explored using luciferase reporter assay and RNA immunoprecipitation assay. KEY FINDINGS: circITCH was downregulated in MM bone marrow specimens and cell lines, as well as BTZ-resistant MM cells. Reduced expression of circITCH was indicative of poor prognosis in MM patients. Upregulation of circITCH enhanced the sensitivity of BTZ-resistant MM cells to BTZ in vitro and in vivo. Furthermore, circITCH was identified as a sponge for miR-615-3p, and PRKCD is confirmed as a direct target of miR-615-3p. Besides, circITCH overexpression enhanced the sensitivity of MM cells to BTZ through miR-615-3p/PRKCD axis. SIGNIFICANCE: circITCH overexpression enhanced the sensitivity of MM cells to BTZ through miR-615-3p/PRKCD axis, providing a novel potential target for combating BTZ resistance in patients with MM.


Assuntos
Antineoplásicos/farmacologia , Bortezomib/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Proteínas Repressoras/genética , Ubiquitina-Proteína Ligases/genética , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Mieloma Múltiplo/genética , Proteína Quinase C-delta/genética , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Analyst ; 145(23): 7603-7608, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-32990694

RESUMO

A new dual-recognition fluorescent biosensor for circulating tumor DNA (ctDNA) detection has been developed, which combines the clamping function of peptide nucleic acid (PNA) and terminal protection of small-molecule-linked DNA (TPSMLD). Taking the tumor-specific E542K mutation and methylation of the PIK3CA gene as the target ctDNA, a low detection limit of 0.3161 pM ctDNA is achieved with good selectivity. This study not only offers a sensitive, selective and accurate ctDNA detection method, but can also be used to detect the target in complex biological samples.


Assuntos
Técnicas Biossensoriais , DNA Tumoral Circulante , Ácidos Nucleicos Peptídicos , DNA Tumoral Circulante/genética , Constrição , DNA/genética , Mutação
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