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1.
BMC Cancer ; 24(1): 573, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724951

RESUMO

BACKGROUND: Microsatellite instability-high (MSI-H) has emerged as a significant biological characteristic of colorectal cancer (CRC). Studies reported that MSI-H CRC generally had a better prognosis than microsatellite stable (MSS)/microsatellite instability-low (MSI-L) CRC, but some MSI-H CRC patients exhibited distinctive molecular characteristics and experienced a less favorable prognosis. In this study, our objective was to explore the metabolic transcript-related subtypes of MSI-H CRC and identify a biomarker for predicting survival outcomes. METHODS: Single-cell RNA sequencing (scRNA-seq) data of MSI-H CRC patients were obtained from the Gene Expression Omnibus (GEO) database. By utilizing the copy number variation (CNV) score, a malignant cell subpopulation was identified at the single-cell level. The metabolic landscape of various cell types was examined using metabolic pathway gene sets. Subsequently, functional experiments were conducted to investigate the biological significance of the hub gene in MSI-H CRC. Finally, the predictive potential of the hub gene was assessed using a nomogram. RESULTS: This study revealed a malignant tumor cell subpopulation from the single-cell RNA sequencing (scRNA-seq) data. MSI-H CRC was clustered into two subtypes based on the expression profiles of metabolism-related genes, and ENO2 was identified as a hub gene. Functional experiments with ENO2 knockdown and overexpression demonstrated its role in promoting CRC cell migration, invasion, glycolysis, and epithelial-mesenchymal transition (EMT) in vitro. High expression of ENO2 in MSI-H CRC patients was associated with worse clinical outcomes, including increased tumor invasion depth (p = 0.007) and greater likelihood of perineural invasion (p = 0.015). Furthermore, the nomogram and calibration curves based on ENO2 showed potential prognosis predictive performance. CONCLUSION: Our findings suggest that ENO2 serves as a novel prognostic biomarker and is associated with the progression of MSI-H CRC.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais , Progressão da Doença , Instabilidade de Microssatélites , Fosfopiruvato Hidratase , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/metabolismo , Prognóstico , Feminino , Masculino , Regulação Neoplásica da Expressão Gênica , Transição Epitelial-Mesenquimal/genética , Pessoa de Meia-Idade , Nomogramas , Análise de Célula Única , Variações do Número de Cópias de DNA
2.
J Gastroenterol Hepatol ; 38(3): 468-475, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36653317

RESUMO

BACKGROUND AND AIM: Severe acute pancreatitis (SAP) in patients progresses rapidly and can cause multiple organ failures associated with high mortality. We aimed to train a machine learning (ML) model and establish a nomogram that could identify SAP, early in the course of acute pancreatitis (AP). METHODS: In this retrospective study, 631 patients with AP were enrolled in the training cohort. For predicting SAP early, five supervised ML models were employed, such as random forest (RF), K-nearest neighbors (KNN), and naive Bayes (NB), which were evaluated by accuracy (ACC) and the areas under the receiver operating characteristic curve (AUC). The nomogram was established, and the predictive ability was assessed by the calibration curve and AUC. They were externally validated by an independent cohort of 109 patients with AP. RESULTS: In the training cohort, the AUC of RF, KNN, and NB models were 0.969, 0.954, and 0.951, respectively, while the AUC of the Bedside Index for Severity in Acute Pancreatitis (BISAP), Ranson and Glasgow scores were only 0.796, 0.847, and 0.837, respectively. In the validation cohort, the RF model also showed the highest AUC, which was 0.961. The AUC for the nomogram was 0.888 and 0.955 in the training and validation cohort, respectively. CONCLUSIONS: Our findings suggested that the RF model exhibited the best predictive performance, and the nomogram provided a visual scoring model for clinical practice. Our models may serve as practical tools for facilitating personalized treatment options and improving clinical outcomes through pre-treatment stratification of patients with AP.


Assuntos
Pancreatite , Humanos , Estudos Retrospectivos , Nomogramas , Índice de Gravidade de Doença , Doença Aguda , Teorema de Bayes , Prognóstico , Aprendizado de Máquina
3.
Eur J Clin Microbiol Infect Dis ; 40(9): 1851-1861, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33792806

RESUMO

This study aims to evaluate the clinical value of PCR-fluorescent probes for detecting the mutation gene associated with extensively drug-resistant tuberculosis (XDR-TB). The molecular species identification of 900 sputum specimens was performed using polymerase chain reaction (PCR)-fluorescent probe. The mutations of the drug resistance genes rpoB, katG, inhA, embB, rpsL, rrs, and gyrA were detected. The conventional drug susceptibility testing (DST) and PCR-directed sequencing (PCR-DS) were carried out as control. DST demonstrated that there were 501 strains of rifampicin resistance, 451 strains of isoniazid resistance, 293 strains of quinolone resistance, 425 strains of streptomycin resistance, 235 strains of ethambutol resistance, and 204 strains of amikacin resistance. Furthermore, 427 (47.44%) or 146 (16.22%) strains were MDR-TB or XDR-TB, respectively. The mutations of the rpoB, katG, inhA, embB, rpsL, rrs, and gyrA genes were detected in 751 of 900 TB patients by PCR-fluorescent probe method, and the rate of drug resistance was 751/900 (83.44%). No mutant genes were detected in the other 149 patients. Compared with DST, the mutant rates of rpoB, katG/inhA, rpsL, rrs, embB, and gyrA of six drugs were higher than 88%; five of six drugs were higher than 90% except for SM (88.11%). The MDR and XDR mutant gene types were found in 398 (42.22%) and 137 (15.22%) samples. PCR-DS was also employed and confirmed the PCR-fluorescent probe method with the accordance rate of 100%. The PCR-fluorescent probe method is rapid and straightforward in detecting XDR-TB genotypes and is worthy of being applied in hospitals.


Assuntos
Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Corantes Fluorescentes/normas , Mutação , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/normas , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla , Corantes Fluorescentes/metabolismo , Corantes Fluorescentes/farmacologia , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Escarro/microbiologia
4.
Mol Cell Probes ; 36: 43-49, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28842221

RESUMO

To definitively diagnose active pulmonary Tuberculosis (TB), Mycobacterium tuberculosis complex (MTBC) bacilli must be identified within clinical specimens from patients. In this study, we introduced a rapid and visual detection method of MTBC using recombinase polymerase amplification (RPA) combined with lateral flow (LF) strips. The LF-RPA assay, read results with naked eyes, could detect as few as 5 genome copies of M. tuberculosis H37Rv (ATCC 27294) per reaction and had no cross-reactions with other control bacteria even using excessive amount of template DNA. The system could work well at a broad range of temperature 25-45 °C and reach detectable level even within 5 min. When testing a total of 137 clinical specimens, the sensitivity and specificity of the LF-RPA assay were 100% (95% CI: 95.94%-100%) and 97.92% (95% CI: 88.93%-99.95%), respectively, compared to culture identification method. Therefore, the LF-RPA system we have demonstrated is a rapid, simple, robust method for MTBC detection which, subject to the availability of a suitable sample extraction method, has the potentiality to diagnose TB at the point-of-care testing.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Kit de Reagentes para Diagnóstico , Recombinases/metabolismo , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura , Fatores de Tempo
5.
Anal Chem ; 87(2): 1202-9, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25495389

RESUMO

A fully automated microsystem consisting of a disposable DNA extraction and PCR microchip, as well as a compact control instrument, has been successfully developed for genetic testing of hereditary hearing loss from human whole blood. DNA extraction and PCR were integrated into a single 15-µL reaction chamber, where a piece of filter paper was embedded for capturing genomic DNA, followed by in-situ PCR amplification without elution. Diaphragm microvalves actuated by external solenoids together with a "one-way" fluidic control strategy operated by a modular valve positioner and a syringe pump were employed to control the fluids and to seal the chamber during thermal cycling. Fully automated DNA extractions from as low as 0.3-µL human whole blood followed by amplifications of 59-bp ß-actin fragments can be completed on the microsystem in about 100 min. Negative control tests that were performed between blood sample analyses proved the successful elimination of any contamination or carryover in the system. To more critically test the microsystem, a two-color multiplex allele-specific PCR (ASPCR) assay for detecting c.176_191del16, c.235delC, and c.299_300delAT mutations in GJB2 gene that accounts for hereditary hearing loss was constructed. Two allele-specific primers, one labeled with TAMRA for wild type and the other with FAM for mutation, were designed for each locus. DNA extraction from blood and ASPCR were performed on the microsystem, followed by an electrophoretic analysis on a portable microchip capillary electrophoresis system. Blood samples from a healthy donor and five persons with genetic mutations were all accurately analyzed with only two steps in less than 2 h.


Assuntos
Análise Mutacional de DNA/instrumentação , DNA/sangue , DNA/genética , Perda Auditiva/sangue , Perda Auditiva/genética , Dispositivos Lab-On-A-Chip , Reação em Cadeia da Polimerase Multiplex/instrumentação , Alelos , Conexina 26 , Conexinas , Desenho de Equipamento , Testes Genéticos/instrumentação , Humanos
6.
Front Microbiol ; 15: 1331656, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841074

RESUMO

Drug-resistant tuberculosis (TB), especially multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB), is one of the urgent clinical problems and public health challenges. Culture-based phenotypic drug susceptibility testing (pDST) is time-consuming, and PCR-based assays are limited to hotspot mutations. In this study, we developed and validated a convenient and efficient approach based on high-throughput nanopore sequencing technology combined with multiplex PCR, namely nanopore targeted sequencing (NTS), to simultaneously sequence 18 genes associated with antibiotic resistance in Mycobacterium tuberculosis (MTB). The analytical performance of NTS was evaluated, and 99 clinical samples were collected to assess its clinical performance. The NTS results showed that MTB and its drug resistance were successfully identified in approximately 7.5 h. Furthermore, compared to the pDST and Xpert MTB/RIF assays, NTS provided much more drug resistance information, covering 14 anti-TB drugs, and it identified 20 clinical cases of drug-resistant MTB. The mutations underlying these drug-resistant cases were all verified using Sanger sequencing. Our approach for this TB drug resistance assay offers several advantages, including being culture-free, efficient, high-throughput, and highly accurate, which would be very helpful for clinical patient management and TB infection control.

7.
Microbiol Spectr ; : e0461522, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36939338

RESUMO

One of the most potent anti-human cytomegalovirus (HCMV) immune mechanisms possessed by host cells is type I interferon (IFN1), which induces the expression of IFN-stimulated genes (ISGs). During this process, mitochondria play an important role in the IFN1 response, and mitofusin 1 (MFN1) is a key regulator of mitochondrial fusion located on the outer mitochondrial membrane. However, the underlying mechanism of MFN1's promotion of IFN1 during HCMV infection still remains unknown. In this study, HCMV infection promoted IFN1 production and enhanced ISG expression. Meanwhile, it promoted the increase of mitochondrial fusion in THP-1 cells and peripheral blood mononuclear cells (PBMCs), especially the expression of MFN1. Phosphorylation of tank binding kinase 1 (p-TBK1), interferon regulatory factor 3 (p-IRF3), and ISGs was significantly decreased in MFN1 or mitochondrial antiviral signaling protein (MAVS)-knockdown THP-1 cells, and MFN1 was constitutively associated with MAVS, positively regulated mitochondrial fusion, and IFN1 production. Knockdown of MFN1 inhibited the MAVS redistribution without affecting the MAVS expression, whereas the HCMV-induced IFN1 production decreased. Conversely, leflunomide could induce the expression of MFN1, thereby producing IFN1 and stimulating the expression of ISG in leflunomide-treated THP-1 cells. These observations reveal that HCMV infection leads to MFN1-mediated redistribution of MAVS and then induces an antiviral response of IFN1 and that the MFN-agonist leflunomide promotes IFN1 responses and may serve as a potential anti-HCMV therapy. IMPORTANCE Human cytomegalovirus (HCMV) infection is ubiquitous and is often asymptomatic in healthy individuals, but it can cause great damage to newborns, AIDS patients, and other immune deficiency patients. In this study, we found that HCMV infection caused mitochondrial fusion, and expression of mitofusin 1 (MFN1), which is a protein associated with mitochondrial antiviral signaling protein (MAVS), positively regulates mitochondrial fusion and HCMV-induced IFN1 response. Knockdown of MFN1 or MAVS can inhibit the HCMV-induced IFN1 production. What is more, confocal laser-scanning microscope showed that knockdown of MFN1 inhibits the HCMV-induced redistribution of MAVS. Conversely, MFN1 agonist leflunomide could induce IFN1 production. In conclusion, we provide new insight into the relationship between MFN1 and IFN1 during HCMV infection and show that MFN1 may serve as a potential strategy against HCMV infection.

8.
ACS Infect Dis ; 9(11): 2306-2315, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37811564

RESUMO

Controlling and mitigating infectious diseases caused by multiple pathogens or pathogens with several subtypes require multiplex nucleic acid detection platforms that can detect several target genes rapidly, specifically, sensitively, and simultaneously. Here, we develop a detection platform, termed Multiplex Assay of RPA and Collateral Effect of Cas12a-based System (MARPLES), based on multiplex nucleic acid amplification and Cas12a ssDNase activation to diagnose these diseases and identify their pathogens. We use the clinical specimens of hand, foot, and mouth disease (HFMD) and influenza A to evaluate the feasibility of MARPLES in diagnosing the disease and identifying the pathogen, respectively, and find that MARPLES can accurately diagnose the HFMD associated with enterovirus 71, coxsackievirus A16 (CVA16), CVA6, or CVA10 and identify the exact types of H1N1 and H3N2 in an hour, showing high sensitivity and specificity and 100% predictive agreement with qRT-PCR. Collectively, our findings demonstrate that MARPLES is a promising multiplex nucleic acid detection platform for disease diagnosis and pathogen identification.


Assuntos
Doença de Mão, Pé e Boca , Vírus da Influenza A Subtipo H1N1 , Ácidos Nucleicos , Humanos , Sistemas CRISPR-Cas , Recombinases , Vírus da Influenza A Subtipo H3N2 , Sensibilidade e Especificidade , Nucleotidiltransferases , Reação em Cadeia da Polimerase Multiplex
9.
J Mol Diagn ; 25(9): 682-691, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37599029

RESUMO

Twin pregnancy constitutes significant risks for maternal and fetal health, which is usually detected by ultrasound examination at early gestation. However, the imaging-based approach may not accurately identify all twins confounded by practical or clinical variables. The analysis of fetal cell-free DNA in noninvasive prenatal screening assays can completement the ultrasound method for twin detection, which differentiates fraternal or identical twins based on their distinct genotypes. Here, a new noninvasive prenatal screening employing high-coverage next-generation sequencing for targeted nucleotide polymorphisms was developed for detection of zygosity and determination of fetal fraction in twin pregnancies. This method utilizes a binary analysis of both the number and allelic fraction of fetus-specific single-nucleotide polymorphisms to infer the zygosity. In 323 samples collected from 215 singleton, 90 dizygotic, and 18 monozygotic twin pregnancies, all 90 dizygotic twins were correctly detected, with a 100% sensitivity and a 100% specificity. In addition, this method can detect complex pregnancies, such as egg donors, contamination, and twins with complete hydatidiform mole. The fetus-specific fetal fraction change was monitored in nine dizygotic twin pregnancies, which demonstrated highly variable dynamics of fetal cell-free DNA turnover up to 7 weeks after twin reduction. Overall, this study provides a new noninvasive prenatal screening strategy for the accurate identification of twin zygosity and quantification of fetal fraction, which has important clinical implications for the management of twin pregnancies.


Assuntos
Ácidos Nucleicos Livres , Gravidez de Gêmeos , Feminino , Gravidez , Humanos , Gravidez de Gêmeos/genética , Polimorfismo de Nucleotídeo Único , Feto , Alelos
10.
Biotechnol Lett ; 34(11): 2007-15, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22829289

RESUMO

MicroRNAs (miRNAs) are a class of small non-coding RNAs involved in gene regulation. Approximately half of miRNAs are located within known genes and called intragenic miRNAs. 408 human intragenic miRNAs and their corresponding host genes were analyzed for genomic organization and functional characterization. Using quantitative real-time PCR, the expression levels of a subset of intragenic miRNAs and their host genes were examined in diverse myeloid leukemia cell lines, and their regulation in response to pharmacological stimuli was also evaluated. Expression of miR-22 strongly correlated with both myeloid leukemia subtypes and the expression of its host gene C17orf91 (p < 0.05). The latter was absent in hematopoietic progenitors but abundant in erythroid and monocytic lineages. These results demonstrated that the expression signatures of miR-22 and C17orf91 are associated with developmental lineages and specific leukemia subtypes.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Leucemia Mieloide/genética , MicroRNAs/genética , Antígenos CD/farmacologia , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hematopoese/efeitos dos fármacos , Hematopoese/genética , Humanos , Leucemia Mieloide/metabolismo , MicroRNAs/biossíntese , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase em Tempo Real
11.
Front Cell Dev Biol ; 10: 798165, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252177

RESUMO

Background: Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with a high mortality rate. PDAC exhibits significant heterogeneity as well as alterations in metabolic pathways that are associated with its malignant progression. In this study, we explored the metabolic and clinical features of a highly malignant subgroup of PDAC based on single-cell transcriptome technology. Methods: A highly malignant cell subpopulation was identified at single-cell resolution based on the expression of malignant genes. The metabolic landscape of different cell types was analyzed based on metabolic pathway gene sets. In vitro experiments to verify the biological functions of the marker genes were performed. PDAC patient subgroups with highly malignant cell subpopulations were distinguished according to five glycolytic marker genes. Five glycolytic highly malignant-related gene signatures were used to construct the glycolytic highly malignant-related genes signature (GHS) scores. Results: This study identified a highly malignant tumor cell subpopulation from the single-cell RNA sequencing (scRNA-seq) data. The analysis of the metabolic pathway revealed that highly malignant cells had an abnormally active metabolism, and enhanced glycolysis was a major metabolic feature. Five glycolytic marker genes that accounted for the highly malignant cell subpopulations were identified, namely, EN O 1, LDHA, PKM, PGK1, and PGM1. An in vitro cell experiment showed that proliferation rates of PANC-1 and CFPAC-1 cell lines decreased after knockdown of these five genes. Patients with metabolic profiles of highly malignant cell subpopulations exhibit clinical features of higher mortality, higher mutational burden, and immune deserts. The GHS score evaluated using the five marker genes was an independent prognostic factor for patients with PDAC. Conclusion: We revealed a subpopulation of highly malignant cells in PDAC with enhanced glycolysis as the main metabolic feature. We obtained five glycolytic marker gene signatures, which could be used to identify PDAC patient subgroups with highly malignant cell subpopulations, and proposed a GHS prognostic score.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35075367

RESUMO

OBJECTIVES: This meta-analysis aimed to assess the efficacy and safety of transcutaneous acupoint electrical stimulation (TEAS) for postoperative pain in laparoscopy. The review has been registered on the "INPLASY" website and the registration number is INPLASY202150101. METHODS: Relevant randomized controlled trials are selected from seven electronic databases (PubMed, the Cochrane Library, Embase, China National Knowledge Infrastructure, Chongqing VIP Information, WanFang Data, and Chinese Biomedical Database) from their inception up to November 30, 2020. Twenty-eight studies were included in this meta-analysis, and the statistical analyses and the exploration of heterogeneity sources were conducted by Stata 15.0 software. Besides, the bias assessment of the included studies was evaluated using the Cochrane risk of bias tool. RESULTS: In total, 28 RCTs covering 2787 participants were included. The meta-analysis suggested that TEAS can effectively relieve pain in the short term after laparoscopy, reduce the postoperative consumption of rescue analgesics, improve the quality of life of patients, and shorten the length of hospitalization. And no serious adverse events are related to TEAS. Therefore, TEAS is relatively safe and efficacy for clinical application. The most used acupoints were Hegu (LI14), Neiguan (PC6), and Zusanli (ST36). CONCLUSIONS: TEAS can be recommended as a complementary and alternative therapy for the treatment of postoperative pain after laparoscopy. However, the included RCTs had some methodological limitations. Therefore, larger-size, more rigorous, and higher-quality RCTs are needed in the future to further explore the efficacy and safety of TEAS for postoperative pain after laparoscopy.

13.
Artigo em Inglês | MEDLINE | ID: mdl-34135986

RESUMO

OBJECTIVE: To systematically evaluate the efficacy and safety of Banxia (Pinellia Tuber) formulae in the treatment of insomnia compared with those of conventional western medicines. METHODS: Randomized controlled trials (RCTs) evaluating the efficacy and safety of Banxia formulae in the treatment of insomnia were searched from the following databases: PubMed, Cochrane Library, EMBASE, the China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP), and Wanfang database. The literature collected was from the time when the databases were established to April 2020. Quality assessment and meta-analysis were conducted by using Cochrane bias risk assessment tool and RevMan 5.2, respectively. Publication bias was assessed by Egger's test. RESULTS: Fourteen RCTs with 910 participants were identified. A total of 46 traditional Chinese medicines involving 2 different dosage forms were used in the included studies. Meta-analysis indicated that Banxia formulae had more significant effects on improving the total effective rate (RR = 1.23, 95% CI 1.16 to 1.31), Pittsburgh Sleep Quality Index (PSQI, MD = -1.05, 95% CI -1.63 to -0.47), and the TCM syndrome score (SMD = -0.78, 95% CI -1.18 to -0.39). Meanwhile, on reducing adverse events, Banxia formulae also showed an advantage (RR = 0.48, 95% CI 0.24 to 0.93). CONCLUSION: According to the current studies, the efficacy of Banxia formulae in the treatment of insomnia is better than that of the conventional western medicines, and its safety is relatively stable. However, due to the limitations of this study, further research and evaluation are needed.

14.
J Cell Physiol ; 215(2): 422-33, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17960585

RESUMO

Transforming growth factor-beta (TGF-beta) signaling is known to depend on the formation of Smad2/3-Smad4 transcription regulatory complexes. However, the signaling functions of Smad2/3-Smad4 during TGF-beta-induced responses are obscure as TGF-beta also initiates a number of other signaling pathways. In this study, we systematically assessed the contribution of TGF-beta-Smad2/3-Smad4 signaling to both target gene transcription and apoptosis. Individual Smads were selectively knocked down in Hep3B cells by stable RNA interference (RNAi). We identified TGF-beta-responsive genes using genome-wide oligonucleotide microarrays and confirmed their dependency on Smad2, Smad3, or Smad4 by the combination of RNAi and microarray assay. The major finding from our microarray analysis was that of the 2,039 target genes seen to be regulated via TGF-beta induction, 190 were differentially transcriptionally controlled by Smad2-Smad4 and Smad3-Smad4 signaling and the latter control mechanism appeared to be functionally more important. We also found indirect evidence of competition between Smad2 and Smad3 for their activation when controlling the transcription of target genes. Functional analysis revealed that Smad3 and Smad4 were the predominant mediators of TGF-beta-induced apoptosis in Hep3B cells. We provide evidence that up-regulation of Bcl-2-interacting mediator of cell death (Bim), under the transcriptional control of Smad3-Smad4 signaling, is crucial to TGF-beta-induced apoptosis in Hep3B cells.


Assuntos
Apoptose/fisiologia , Transdução de Sinais/fisiologia , Proteínas Smad/metabolismo , Transcrição Gênica/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/fisiologia , Humanos , Proteínas de Membrana/metabolismo , Análise em Microsséries , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas/metabolismo , Interferência de RNA , Proteínas Smad/genética , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad4/metabolismo , Transfecção , Fator de Crescimento Transformador beta/farmacologia , Regulação para Cima
15.
J Neurosci Methods ; 170(1): 123-9, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18295341

RESUMO

Technological improvement of measurements for the electrical recordings from individual neurons within network is essential in neuroscience today. Here, we present a novel automatic positioning and sensing microelectrode array (APSMEA), which simultaneously positioned desired number of neurons onto 48 recording microelectrodes automatically and scathelessly by use of negative dielectrophoretic (DEP) forces, and facilitated the measurement of the electrophysiological activities of neuronal populations after functional synaptic connections formed between neurons. The results of multi-site electrophysiological recordings during drug administration also demonstrated the application of APSMEA in bioassay with cultured rat cortical neurons. Therefore, this device should benefit the investigation of neuronal networks in vitro with more comprehensive electrophysiological experiments, and also promise the possibility of a modular device for both cell manipulation and cell-based biosensor on microchip.


Assuntos
Eletrofisiologia/instrumentação , Microeletrodos , Animais , Técnicas Biossensoriais , Células Cultivadas , Eletroforese , Microcomputadores , Rede Nervosa/fisiologia , Neurônios/fisiologia , Ratos
16.
Biosens Bioelectron ; 22(11): 2478-84, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17071071

RESUMO

Microelectrode arrays (MEAs) provide a means to investigate the electrophysiological behavior of neuronal systems through the measurements from neuronal culture preparations. Changes in activity patterns of neuronal networks are usually detected by applying neural chemicals. Because of the difficulties of fabricating the arrays, and the delicate and less reliable properties of cortical neurons, MEA-based systems with cortical neuronal networks for neurophamacological applications are technically difficult, therefore restricting their utility. Here, we report a new approach to the development of such MEA-based system with sensitive and durable MEAs conveniently fabricated and the culture conditions optimized. Upon growth differentiation, cortical neurons, cultured directly on MEAs, reach a developmentally stable and reliable activity state. With this system, we monitored the global spontaneous activities of neuronal networks and demonstrated the fine discrimination for specific substances and unique property of cortical neurons, which validated both the applicability and necessity of such system in pharmacological bioassay.


Assuntos
Potenciais de Ação/fisiologia , Bioensaio/instrumentação , Técnicas Biossensoriais/instrumentação , Técnicas de Cultura de Células/instrumentação , Microeletrodos , Neurônios/fisiologia , Neurotransmissores/administração & dosagem , Potenciais de Ação/efeitos dos fármacos , Animais , Bioensaio/métodos , Técnicas Biossensoriais/métodos , Técnicas de Cultura de Células/métodos , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiologia , Avaliação Pré-Clínica de Medicamentos/instrumentação , Avaliação Pré-Clínica de Medicamentos/métodos , Estimulação Elétrica/instrumentação , Estimulação Elétrica/métodos , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiologia , Neurônios/efeitos dos fármacos , Neurofarmacologia/instrumentação , Neurofarmacologia/métodos , Ratos , Ratos Sprague-Dawley
17.
Sci Rep ; 7(1): 6441, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28743917

RESUMO

An air-insulated microfluidic chip was designed for the automatic centrifugal distribution of samples to 24-test cells, enabling the parallel identification of multiple clinical pneumonia-related pathogens in 1.45-µL reactions without cross-contamination in 45 min. A portable nucleic acid analyzer that integrates mechanical, confocal optical, electronic, and software functions was also developed to collect fluorescence data in a Ø3 mm imaging field near the optical diffraction limit for highly sensitive fluorescence detection of nucleic acid amplification in real time. This microfluidic chip-based portable nucleic acid analyzer could detect low abundance nucleic acids present at as few as 10 copies. In a blinded experiment, specific identification of Mycoplasma pneumoniae, Staphylococcus aureus, and methicillin-resistant S. aureus was achieved with 229 clinical patient sputum samples. The total coincidence rate of our system and traditional RT-PCR with an ABI 7500 was 99.56%. Four samples accounting for the 0.44% inconformity were retested by gene sequencing, revealing that our system reported the correct results. This novel microfluidic chip-based detection system is cost-effective, rapid, sensitive, specific, and has a relatively high throughput for parallel identification, which is especially suitable for resource-limited facilities/areas and point-of-care testing.


Assuntos
Técnicas Bacteriológicas/métodos , Dispositivos Lab-On-A-Chip , Pneumonia por Mycoplasma/microbiologia , Pneumonia Estafilocócica/microbiologia , Adolescente , Adulto , Técnicas Bacteriológicas/economia , Técnicas Bacteriológicas/instrumentação , Desenho de Equipamento , Feminino , Humanos , Limite de Detecção , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/economia , Técnicas de Diagnóstico Molecular/instrumentação , Técnicas de Diagnóstico Molecular/métodos , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/isolamento & purificação , Mycoplasma pneumoniae/patogenicidade , Técnicas de Amplificação de Ácido Nucleico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade
18.
PLoS One ; 12(3): e0169219, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28273078

RESUMO

The unparalleled heterogeneity in genetic causes of hearing loss along with remarkable differences in prevalence of causative variants among ethnic groups makes single gene tests technically inefficient. Although hundreds of genes have been reported to be associated with nonsyndromic hearing loss (NSHL), GJB2, GJB6, SLC26A4, and mitochondrial (mt) MT-RNR1 and MTTS are the major contributors. In order to provide a faster, more comprehensive and cost effective assay, we constructed a DNA fluidic array, CapitalBioMiamiOtoArray, for the detection of sequence variants in five genes that are common in most populations of European descent. They consist of c.35delG, p.W44C, p.L90P, c.167delT (GJB2); 309kb deletion (GJB6); p.L236P, p.T416P (SLC26A4); and m.1555A>G, m.7444G>A (mtDNA). We have validated our hearing loss array by analyzing a total of 160 DNAs samples. Our results show 100% concordance between the fluidic array biochip-based approach and the established Sanger sequencing method, thus proving its robustness and reliability at a relatively low cost.


Assuntos
DNA/metabolismo , Surdez/genética , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Análise de Sequência com Séries de Oligonucleotídeos , População Branca/genética , Conexina 26 , Conexina 30 , Conexinas/genética , Conexinas/metabolismo , DNA/química , DNA/genética , DNA/isolamento & purificação , DNA Mitocondrial/química , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Surdez/patologia , Humanos , Proteínas de Membrana Transportadoras/genética , Mitocôndrias/genética , Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Transportadores de Sulfato
19.
Biomed Rep ; 4(6): 737-740, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27284415

RESUMO

The present cross-sectional study consisted of 18,265 Chinese patients not previously diagnosed with diabetes mellitus, and who underwent physical examination at the Third People's Hospital of Shenzhen between June 2014 and May 2015 (mean patient age, 51.312±15.252 years). The study was composed of 11,770 males and 6,495 females. The aim was to investigate the association between glycated hemoglobin A1c (HbA1c) levels, gender and age. HbA1c values were measured using a Bio-Rad VARIANT™ II HbA1c Reorder Pack. All data was collected for analysis of the HbA1c levels in different gender and age groups, in order to investigate the association between HbA1c levels and age. Analysis of the 18,265 total cases and 16,734 cases with HbA1c levels <6.5%, demonstrated a positive correlation between levels of HbA1c and patient age. Linear regression for patient age and HbA1c levels demonstrated that HbA1c (%) = 0.020 × age (years) + 4.523 (r=0.369, P<0.0001) and HbA1c (%) = 0.014 × age (years) + 4.659 (r=0.485, P<0.0001), respectively. HbA1c levels of the male group were significantly higher than those of the female group (P<0.0001). Furthermore, in different gender groups, HbA1c levels gradually rose with increasing age. Therefore, HbA1c levels are associated with age and gender in Chinese populations, and this should be considered when selecting HbA1c as a criterion for future diabetes screening.

20.
Lab Chip ; 16(1): 86-95, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26568290

RESUMO

A fully integrated and automated microsystem consisting of low-cost, disposable plastic chips for DNA extraction and PCR amplification combined with a reusable glass capillary array electrophoresis chip in a modular-based format was successfully developed for warfarin pharmacogenetic testing. DNA extraction was performed by adopting a filter paper-based method, followed by "in situ" PCR that was carried out directly in the same reaction chamber of the chip without elution. PCR products were then co-injected with sizing standards into separation channels for detection using a novel injection electrode. The entire process was automatically conducted on a custom-made compact control and detection instrument. The limit of detection of the microsystem for the singleplex amplification of amelogenin was determined to be 0.625 ng of standard K562 DNA and 0.3 µL of human whole blood. A two-color multiplex allele-specific PCR assay for detecting the warfarin-related single-nucleotide polymorphisms (SNPs) 6853 (-1639G>A) and 6484 (1173C>T) in the VKORC1 gene and the *3 SNP (1075A>C) in the CYP2C9 gene was developed and used for validation studies. The fully automated genetic analysis was completed in two hours with a minimum requirement of 0.5 µL of input blood. Samples from patients with different genotypes were all accurately analyzed. In addition, both dried bloodstains and oral swabs were successfully processed by the microsystem with a simple modification to the DNA extraction and amplification chip. The successful development and operation of this microsystem establish the feasibility of rapid warfarin pharmacogenetic testing in routine clinical practice.


Assuntos
Automação , Análise Mutacional de DNA , DNA/genética , Farmacogenética/métodos , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único/genética , Varfarina/farmacologia , Amelogenina/genética , DNA/análise , DNA/sangue , DNA/isolamento & purificação , Análise Mutacional de DNA/instrumentação , Eletrodos , Eletroforese Capilar/instrumentação , Genótipo , Humanos , Células K562 , Tamanho da Partícula , Farmacogenética/instrumentação , Reação em Cadeia da Polimerase/instrumentação , Propriedades de Superfície
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