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1.
J Magn Reson Imaging ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38206839

RESUMO

BACKGROUND: Hemangioblastoma (HB) is a highly vascularized tumor most commonly occurring in the posterior cranial fossa, requiring accurate preoperative diagnosis to avoid accidental intraoperative hemorrhage and even death. PURPOSE: To accurately distinguish HBs from other cerebellar-and-brainstem tumors using a convolutional neural network model based on a contrast-enhanced brain MRI dataset. STUDY TYPE: Retrospective. POPULATION: Four hundred five patients (182 = HBs; 223 = other cerebellar-and brainstem tumors): 305 cases for model training, and 100 for evaluation. FIELD STRENGTH/SEQUENCE: 3 T/contrast-enhanced T1-weighted imaging (T1WI + C). ASSESSMENT: A CNN-based 2D classification network was trained by using sliced data along the z-axis. To improve the performance of the network, we introduced demographic information, various data-augmentation methods and an auxiliary task to segment tumor region. Then, this method was compared with the evaluations performed by experienced and intermediate-level neuroradiologists, and the heatmap of deep feature, which indicates the contribution of each pixel to model prediction, was visualized by Grad-CAM for analyzing the misclassified cases. STATISTICAL TESTS: The Pearson chi-square test and an independent t-test were used to test for distribution difference in age and sex. And the independent t-test was exploited to evaluate the performance between experts and our proposed method. P value <0.05 was considered significant. RESULTS: The trained network showed a higher accuracy for identifying HBs (accuracy = 0.902 ± 0.031, F1 = 0.891 ± 0.035, AUC = 0.926 ± 0.040) than experienced (accuracy = 0.887 ± 0.013, F1 = 0.868 ± 0.011, AUC = 0.881 ± 0.008) and intermediate-level (accuracy = 0.827 ± 0.037, F1 = 0.768 ± 0.068, AUC = 0.810 ± 0.047) neuroradiologists. The recall values were 0.910 ± 0.050, 0.659 ± 0.084, and 0.828 ± 0.019 for the trained network, intermediate and experienced neuroradiologists, respectively. Additional ablation experiments verified the utility of the introduced demographic information, data augmentation, and the auxiliary-segmentation task. DATA CONCLUSION: Our proposed method can successfully distinguish HBs from other cerebellar-and-brainstem tumors and showed diagnostic efficiency comparable to that of experienced neuroradiologists. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

2.
J Magn Reson Imaging ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236785

RESUMO

BACKGROUND: Quantitative in-situ pH mapping of gliomas is important for therapeutic interventions, given its significant association with tumor progression, invasion, and metastasis. Although chemical exchange saturation transfer (CEST) offers a noninvasive way for pH imaging based on the pH-dependent exchange rate (ksw ), the reliable quantification of ksw in glioma remains constrained due to technical challenges. PURPOSE: To quantify the pH of gliomas by measuring the proton exchange rate through optimized omega plot analysis. STUDY TYPE: Prospective. PHANTOMS/ANIMAL MODEL/SUBJECTS: Creatine and murine brain lysates phantoms, six rats with glioma xenograft model, and three patients with World Health Organization grade 2-4 gliomas. FIELD STRENGTH/SEQUENCE: 11.7 T, 7.0 T, CEST imaging, T2 -weighted (T2 W) imaging, and T1 -mapping. ASSESSMENT: Omega plot analysis, quasi-steady-state (QUASS) analysis, multi-pool Lorentzian fitting, amine and amide concentration-independent detection, pH enhanced method with the combination of amide and guanidyl (pHenh ), and magnetization transfer ratio (MTR) were utilized for pH metric quantification. The clinical outcomes were determined through radiologic follow-up and histopathological analysis. STATISTICAL TESTS: Mann-Whitney U test was performed to compare glioma with normal tissue, and Pearson's correlation analysis was used to assess the relationship between ksw and other parameters. RESULTS: In vitro experiments reveal that the determined ksw at 2 ppm increases exponentially with pH (creatine phantoms: ksw = 106 + 0.147 × 10(pH-4.198) ; lysates: ksw = 185.1 + 0.101 × 10(pH-3.914) ). Omega plot analysis exhibits a linear correlation between 1/MTRRex and 1/ω1 2 in the glioma xenografts (R2 > 0.98) and glioma patients (R2 > 0.99). The exchange rate in the rat glioma decreases compared to the contralateral normal tissue (349.46 ± 30.40 s-1 vs. 403.54 ± 51.01 s-1 , P = 0.025), while keeping independence from changes in concentration (r = 0.5037, P = 0.095). Similar pattern was observed in human data. DATA CONCLUSION: Utilizing QUASS-based, spillover-, and MT-corrected omega plot analysis for the measurement of exchange rates, offers a feasible method for quantifying pH within glioma. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 1.

3.
J Viral Hepat ; 30(6): 489-496, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36807422

RESUMO

In 2020, China conducted a nationwide, sero-epidemiological, cross-sectional survey of viral hepatitis. The stratified multi-stage cluster random sampling method was used to select the permanent population aged 1-69 years, followed by questionnaire survey and sample collection and detection of the serological markers of hepatitis B (HBV) and hepatitis C viruses (HCV). A total of 4747 individuals aged 1-69 years were investigated in Zhejiang Province. The positive rates of hepatitis B surface antigen and anti-HCV were 4.3% and 0%, respectively. Compared to a similar sero-epidemiological survey in 1992, the 2020 survey showed that the HBV infection rate in Zhejiang Province decreased by 56.5%. In both surveys, HBV infection rate increased with age (in 1992, χ2  = 185.866, p = .000; in 2020, χ2  = 1383.836, p = .000). Compared with 1992, the positive anti-HCV rate in those aged 1-69 years in 2020 decreased by 100.0%. This result showed that the HBV vaccine and blood screening to prevent HBV and HCV infection significantly decreased the infection rate of HBV and HCV in the younger generation of Zhejiang province. However, the rate of HBV carriers aged 30-69 years was still high, which underscores the need to strengthen the management and treatment of chronic HBV infection. Hence, Zhejiang province can eliminate the public health threat of viral hepatitis.


Assuntos
Hepatite B , Hepatite C , Humanos , Estudos Soroepidemiológicos , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Hepacivirus , Vírus da Hepatite B , China/epidemiologia , Prevalência , Inquéritos e Questionários , Estudos Transversais , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Lactente , Pré-Escolar , Criança
4.
BMC Womens Health ; 23(1): 487, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37705033

RESUMO

BACKGROUND: The objective of the present study was to investigate whether associations exist between inflammatory biomarkers and all-cause mortality and cardiovascular disease (CVD) mortality in women with postmenopausal osteoporosis (PMOP) or osteopenia. METHODS: In this retrospective cohort study, data were obtained from the National Health and Nutrition Examination Survey database from the years 2007 to 2010, 2013 to 2014, and 2017 to 2018. The inflammatory biomarkers including neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), neutrophil × platelet/lymphocyte (SII), neutrophil × monocyte/lymphocyte (SIRI), and neutrophil × monocyte × platelet/lymphocyte ratio (AISI) were calculated. RESULTS: A total of 2,834 women were included, with a median survival of 113.51 (3.15) months. During follow-up, 602 women died of all-cause mortality and 185 women died of CVD. NLR, MLR, SIRI, and AISI were significantly associated with all-cause mortality in postmenopausal women with osteoporosis or osteopenia. NLR, MLR, SIRI, and AISI were related to CVD mortality in postmenopausal women with osteoporosis or osteopenia (All P < 0.05). Based on the results of the subgroup analysis, AISI, SIRI, and MLR were associated with all-cause mortality and CVD mortality in postmenopausal women with PMOP or osteopenia who had a history of CVD and diabetes. AISI, SII, MLR, and NLR were associated with all-cause mortality and CVD mortality in PMOP or osteopenia women with a body mass index (BMI) > 25 kg/m2. PLR was associated with all-cause mortality in PMOP or osteopenia women aged ≥ 65 years. CONCLUSION: Inflammatory biomarkers were correlated with mortality risk in the PMOP or osteopenia population. This finding may be helpful for the prognosis management of PMOP or osteopenia in postmenopausal women.


Assuntos
Doenças Ósseas Metabólicas , Doenças Cardiovasculares , Osteoporose Pós-Menopausa , Osteoporose , Feminino , Humanos , Inquéritos Nutricionais , Pós-Menopausa , Estudos Retrospectivos
5.
IUBMB Life ; 71(12): 1906-1915, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31317647

RESUMO

piRNAs are a large class of small noncoding RNA that interact with an animal-specific class of Argonaute proteins, P-element induced wimpy proteins. piRNAs were initially discovered in mouse testes to be a fundamental component of spermatogenesis. Outside of the germline, piRNAs were found to function in embryogenesis, development, regeneration and cancer cells. However, despite a decade of scrutiny, functional understanding of this class of small RNAs remains very limited. To determine whether there are piRNAs present and involved in the cellular reprogramming process, we extracted piwi-interacting RNA (piRNA) signatures from a small RNA deep sequencing data set of mouse embryonic fibroblasts (MEFs), mouse embryonic stem cells (mESCs) and reprogrammed stem cells by three different technologies. We successfully identified three piRNA families specifically expressed in these reprogrammed stem cells. Meanwhile, there were almost no piRNAs observed in MEFs and mESCs. Further analysis indicated that these piRNAs may associate with the reprogramming process but not cellular pluripotency. Target gene prediction suggested that at least one of piRNAs, piR-mmu-64162, may take part in the reprogramming process by regulating cell senescence. Overall, we firstly identified the potential reprogramming associated piRNAs, shedding new light on piRNA functions.


Assuntos
Fibroblastos/citologia , Células-Tronco Pluripotentes Induzidas/fisiologia , RNA Interferente Pequeno/genética , Animais , Embrião de Mamíferos/citologia , Fibroblastos/fisiologia , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Células-Tronco Pluripotentes Induzidas/citologia , Camundongos
6.
Acta Biochim Biophys Sin (Shanghai) ; 49(7): 635-642, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28510621

RESUMO

Mouse miR-290 cluster miRNAs are expressed specifically in early embryos and embryonic germ cells. These miRNAs play critical roles in the maintenance of pluripotency and self-renewal. Here, we showed that Cyclin D1 is a direct target gene of miR-290 cluster miRNAs. Negative relationships between the expression of Cyclin D1 protein and miR-290 cluster miRNAs in pluripotent and non-pluripotent cells, as well as in differentiating CGR8 cells were observed. Inhibition of miR-290 cluster miRNAs could arrest cells at the G1 phase and slow down the cell proliferation in CGR8 mouse stem cells. Since miR-290 cluster miRNAs are the most dominant stem-cell-specific miRNAs, our results revealed an important cause for the absence of Cyclin D1 in mouse embryonic stem cells.


Assuntos
Ciclina D1/análise , MicroRNAs/fisiologia , Células-Tronco Embrionárias Murinas/química , Animais , Proliferação de Células , Células Cultivadas , Ciclina D1/genética , Quinase 4 Dependente de Ciclina/fisiologia , Quinase 6 Dependente de Ciclina/fisiologia , Fase G1 , Camundongos , Células-Tronco Embrionárias Murinas/citologia
7.
Tumour Biol ; 36(4): 2481-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25501507

RESUMO

MicroRNAs (MiRNAs) are small non-coding RNA molecules which act as important regulators of post-transcriptional gene expression by binding 3'-untranslated region (3'-UTR) of target messenger RNA (mRNA). In this study, we analyzed miRNA-34a (miR-34a) as a tumor suppressor in non-small cell lung cancer (NSCLC) H1299 cell line. The expression level of miR-34a in four different NSCLC cell lines, H1299, A549, SPCA-1, and HCC827, was significantly lower than that in the non-tumorigenic bronchial epithelium cell line BEAS-2B. In human NSCLC tissues, miR-34a expression level was also significantly decreased in pT2-4 compared with the pT1 group. Moreover, miR-34a mimic could inhibit the proliferation and triggered apoptosis in H1299 cells. Luciferase assays revealed that miR-34a inhibited TGFßR2 expression by targeting one binding site in the 3'-UTR of TGFßR2 mRNA. Quantitative real-time PCR (qRT-PCR) and Western blot assays verified that miR-34a reduced TGFßR2 expression at both mRNA and protein levels. Furthermore, downregulation of TGFßR2 by siRNA showed the same effects on the proliferation and apoptosis as miR-34a mimic in H1299 cells. Our results demonstrated that miR-34a could inhibit the proliferation and promote the apoptosis of H1299 cells partially through the downregulation of its target gene TGFßR2.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Proliferação de Células/genética , MicroRNAs/genética , Proteínas Serina-Treonina Quinases/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Regiões 3' não Traduzidas/genética , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/biossíntese , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/biossíntese , RNA Interferente Pequeno/genética , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/genética
9.
Acta Biochim Biophys Sin (Shanghai) ; 47(3): 224-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25662391

RESUMO

MicroRNAs (miRNAs) are a class of non-coding, regulatory small RNAs of ∼22 nt. It was implicated that these small RNAs play critical roles in various important biological processes. During development, some miRNAs are specifically expressed in individual tissues and at particular developmental stages. Many miRNAs show distinct expression patterns in the development of central nervous system, including spinal cord. In this study, we first reported the miRNAs expression in the development of mouse spinal cord. Differentially expressed miRNAs in embryonic (day 13.5) and neonatal mice spinal cords were identified. The predicted target genes of the differentially expressed miRNAs were subject to gene ontology and KEGG pathway analysis, and several nervous development-related pathways were enriched, implying that these miRNAs may be involved in these pathways that regulate mouse spinal cord development.


Assuntos
MicroRNAs/genética , MicroRNAs/metabolismo , Medula Espinal/embriologia , Medula Espinal/metabolismo , Animais , Animais Recém-Nascidos , Regulação para Baixo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
10.
Acta Biochim Biophys Sin (Shanghai) ; 47(8): 630-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26124189

RESUMO

MicroRNAs play important roles in carcinogenesis and tumor progress. Lung cancer is the leading cause of cancer mortality worldwide. In this study, the function of miR-181a-5p was investigated in non-small-cell lung cancer (NSCLC). Results showed that miR-181a-5p was significantly decreased in NSCLC tissues and cell lines. The proliferation and migration of A549 cells transfected with miR-181a-5p mimic was significantly inhibited. Luciferase activity assay results demonstrated that two binding sites of Kras could be directly targeted by miR-181a-5p. Furthermore, Kras was down-regulated by miR-181a-5p at both transcriptional and translational levels. SiRNA-mediated Kras down-regulation could mimic the effects of miR-181a-5p mimic in A549 cells. Our findings suggest that miR-181a-5p plays a potential role in tumor suppression by partially targeting Kras and has the potential therapeutic application in NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Terapia de Alvo Molecular , Transfecção
11.
BMC Genomics ; 15: 488, 2014 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-24942538

RESUMO

BACKGROUND: Reprogrammed cells, including induced pluripotent stem cells (iPSCs) and nuclear transfer embryonic stem cells (NT-ESCs), are similar in many respects to natural embryonic stem cells (ESCs). However, previous studies have demonstrated that iPSCs retain a gene expression signature that is unique from that of ESCs, including differences in microRNA (miRNA) expression, while NT-ESCs are more faithfully reprogrammed cells and have better developmental potential compared with iPSCs. RESULTS: We focused on miRNA expression and explored the difference between ESCs and reprogrammed cells, especially ESCs and NT-ESCs. We also compared the distinct expression patterns among iPSCs, NT-ESCs and NT-iPSCs. The results demonstrated that reprogrammed cells (iPSCs and NT-ESCs) have unique miRNA expression patterns compared with ESCs. The comparison of differently reprogrammed cells (NT-ESCs, NT-iPSCs and iPSCs) suggests that several miRNAs have key roles in the distinct developmental potential of reprogrammed cells. CONCLUSIONS: Our data suggest that miRNAs play a part in the difference between ESCs and reprogrammed cells, as well as between MEFs and pluripotent cells. The variation of miRNA expression in reprogrammed cells derived using different reprogramming strategies suggests different characteristics induced by nuclear transfer and iPSC generation, as well as different developmental potential among NT-ESCs, iPSCs and NT-iPSCs.


Assuntos
Células-Tronco Embrionárias/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , MicroRNAs/genética , Transcriptoma , Animais , Linhagem Celular , Reprogramação Celular , Mapeamento Cromossômico , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo
12.
IEEE Int Conf Robot Autom ; 2024: 8209-8215, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39421218

RESUMO

A surgeon's physiological hand tremor can significantly impact the outcome of delicate and precise retinal surgery, such as retinal vein cannulation (RVC) and epiretinal membrane peeling. Robot-assisted eye surgery technology provides ophthalmologists with advanced capabilities such as hand tremor cancellation, hand motion scaling, and safety constraints that enable them to perform these otherwise challenging and high-risk surgeries with high precision and safety. Steady-Hand Eye Robot (SHER) with cooperative control mode can filter out surgeon's hand tremor, yet another important safety feature, that is, minimizing the contact force between the surgical instrument and sclera surface for avoiding tissue damage cannot be met in this control mode. Also, other capabilities, such as hand motion scaling and haptic feedback, require a teleoperation control framework. In this work, for the first time, we implemented a teleoperation control mode incorporated with an adaptive sclera force control algorithm using a PHANTOM Omni haptic device and a force-sensing surgical instrument equipped with Fiber Bragg Grating (FBG) sensors attached to the SHER 2.1 end-effector. This adaptive sclera force control algorithm allows the robot to dynamically minimize the tool-sclera contact force. Moreover, for the first time, we compared the performance of the proposed adaptive teleoperation mode with the cooperative mode by conducting a vessel-following experiment inside an eye phantom under a microscope.

13.
ROMAN ; 2023: 2359-2365, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38347956

RESUMO

Cooperative robots for intraocular surgery allow surgeons to perform vitreoretinal surgery with high precision and stability. Several robot structural designs have shown capabilities to perform these surgeries. This research investigates the comparative performance of a serial and parallel cooperative-controlled robot in completing a retinal vessel-following task, with a focus on human-robot interaction performance and user experience. Our results indicate that despite differences in robot structure and interaction forces and torques, the two robots exhibited similar levels of performance in terms of general robot-to-patient interaction and average operating time. These findings have implications for the development and implementation of surgical robotics, suggesting that both serial and parallel cooperative-controlled robots can be effective for vitreoretinal surgery tasks.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38082798

RESUMO

Multi-tile image stitching aims to merge multiple natural or biomedical images into a single mosaic. This is an essential step in whole-slide imaging and large-scale pathological imaging systems. To tackle this task, a multi-step framework is usually used by first estimating the optimal transformation for each image and then fusing them into a whole image. However, the traditional approaches are usually time-consuming and require manual adjustments. Advances in deep learning techniques provide an end-to-end solution to register and fuse information of multiple tile images. In this paper, we present a deep learning model for multi-tile biomedical image stitching, namely MosaicNet, consisting of an aligning network and a fusion network. We trained the MosaicNet network on a large simulation dataset based on the VOC2012 dataset and evaluated the model on multiple types of datasets, including simulated natural images, mouse brain T2-weighted Magnetic Resonance Imaging (T2w-MRI) data, and mouse brain polarization sensitive-optical coherence tomography (PS-OCT) data. Our method outperformed traditional approaches on both natural images and brain imaging data. The proposed method is robust to different settings of hyper-parameters and shows high computational efficiency, up to approximately 32 times faster than the conventional methods.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Animais , Camundongos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Simulação por Computador , Encéfalo/diagnóstico por imagem
15.
IUBMB Life ; 64(7): 612-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22593088

RESUMO

Analysis of mature microRNA (miRNA) expression is important to understand its physiological functions and pathological implications. Microarray is a powerful technology to profile global miRNA expression. In this study, we developed a rapid miRNA labeling method by which miRNA was directly labeled in total RNA for microarray detection. This method consists of RNA tailing by poly(A) polymerase, reverse transcription, and template-switching by moloney murine leukemia virus (MMLV) reverse transcriptase. After these reactions, the small RNA cDNA was ready for labeling for microarray detection. The whole process of prearray sample preparation was dramatically shortened to 2 h. Furthermore, this method allows very limited starting total RNA (100 ng) for microarray analysis. Our data showed that the results from our method were highly consistent with that of real-time polymerase chain reaction (PCR).


Assuntos
Regulação da Expressão Gênica , MicroRNAs/genética , Análise em Microsséries/métodos , RNA/metabolismo , Animais , DNA Complementar/metabolismo , Perfilação da Expressão Gênica , Humanos , Camundongos , MicroRNAs/metabolismo , Vírus da Leucemia Murina de Moloney/genética , Reação em Cadeia da Polimerase , Polinucleotídeo Adenililtransferase/metabolismo , Neoplasias Gástricas/metabolismo , Fatores de Tempo
16.
Acta Biochim Biophys Sin (Shanghai) ; 44(2): 129-35, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22189512

RESUMO

MicroRNAs (miRNAs) constitute a critically important class of non-translated, small RNAs, which post-transcriptionally regulate gene expression via one of the multiple mechanisms. To profile miRNA expression, microarrays have been extensively applied to the high-throughput detection of miRNAs. Here, we described a novel 3'-end miRNA-labeling method for microarray detection by terminal-deoxynucleotidyl transferase (TdT). TdT can catalyze the formation of polynucleotides at RNA receptor molecule with deoxycytidine triphosphate (dCTP). Using this activity, miRNA was successfully labeled by adding fluorescence dCTPs to its 3'-end. This labeling method was very simple and sensitive. The TdT-labeling method can detect as little as 0.04 fmol of synthetic small RNA, and produce precise and accurate measurements that span a linear dynamic range from 0.04 to 5 fmol of synthetic small RNA. The high consistency of miRNA expression data between our TdT method and real-time polymerase chain reaction analysis indicated the reliability and accuracy of the TdT method. Taken together, these results emphasize the immense potential application of the TdT-labeling method for sensitive and high-throughput microarray analysis of miRNA expression.


Assuntos
DNA Nucleotidilexotransferase , MicroRNAs/química , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Sequência de Bases , Linhagem Celular , Sondas de DNA/genética , Ensaios de Triagem em Larga Escala/métodos , Ensaios de Triagem em Larga Escala/estatística & dados numéricos , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/estatística & dados numéricos , Sensibilidade e Especificidade
17.
Acta Biochim Biophys Sin (Shanghai) ; 44(3): 233-40, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22240259

RESUMO

The expression of 350 microRNAs (miRNAs) in epididymis of rat from postnatal development to adult (from postnatal days 7-70) was profiled with home-made miRNA microarray. Among them, 48 miRNAs changed significantly, in which the expression of miR-200a increased obviously with time, in a good agreement with that obtained from northern blot analysis. The real-time quantitative-polymerase chain reaction result indicated that temporal expression of rat ß-catenin was exactly inversed to that of miR-200a during rat epididymal development, implying that miR-200a might also target ß-catenin mRNA in rat epididymis as reported by Saydam et al. in humans. The bioinformatic analysis indicated that 3' untranslated region of rat ß-catenin mRNA did contain a putative binding site for miR-200a. Meanwhile, it was found that the sequence of this binding site was different from that of human ß-catenin mRNA with a deletion of two adjacent nucleotides (U and C). But the results of luciferase targeting assay in HEK 293T cells and the overexpression of miR-200a in rat NRK cells demonstrated that miR-200a did target rat ß-catenin mRNA and cause the suppression of its expression. All these results show that miR-200a should be involved in rat epididymal development by targeting ß-catenin mRNA of rat and suppressing its expression.


Assuntos
Epididimo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/biossíntese , beta Catenina/metabolismo , Animais , Sequência de Bases , Clonagem Molecular , Análise por Conglomerados , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Masculino , Modelos Genéticos , Dados de Sequência Molecular , Ratos
18.
J Allergy Clin Immunol ; 127(6): 1447-56.e6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21377197

RESUMO

BACKGROUND: IL-2 combined with dexamethasone can upregulate regulatory T (Treg) cells, but the mechanism is still under exploration. OBJECTIVE: Although previous studies focused on upregulating Treg cells in normal mice, here we investigated whether the IL-2 and dexamethasone combination treatment can upregulate Treg cells in pathological conditions, specifically in alleviating allergic airway disease. We also examined the potential pathway involved in Treg cell upregulation by IL-2 and dexamethasone. METHODS: We evaluated the dose of IL-2 and dexamethasone required to upregulate Treg cells in vivo and in vitro. We also tested IL-2 and dexamethasone in the intervention of allergic airway disease in a murine model. RESULTS: We found that administration of 400,000 IU of IL-2 and 0.1 mg of dexamethasone per mouse was effective in upregulating Treg cells, as well as in alleviating allergic airway disease in an established animal model, but this phenomenon disappeared after anti-CD25 antibody administration. We discovered that an in vitro low dose of IL-2 can protect Treg cells did not protect CD4(+)CD25(-) cells from dexamethasone-induced apoptosis by affecting forkhead box O3a phosphorylation through the Akt and serum and glucocorticoid-induced protein kinase pathways. CONCLUSIONS: IL-2/dexamethasone treatment can alleviate existing allergic airway diseases by upregulating Treg cells in vivo. A low dose of IL-2 (10(-9) to 10(-11) mol/L) can protect Treg cells but not CD4(+)CD25(-) cells from dexamethasone-induced apoptosis in vitro, thereby explaining a possible mechanism of increased proportion of Treg cells.


Assuntos
Dexametasona/administração & dosagem , Interleucina-2/administração & dosagem , Hipersensibilidade Respiratória/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Técnicas In Vitro , Subunidade alfa de Receptor de Interleucina-2/antagonistas & inibidores , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Recombinantes/administração & dosagem , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/patologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
19.
Chemosphere ; 307(Pt 4): 136118, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36007746

RESUMO

In this article, a novel 2D/2D ultrathin Ti3C2/SnS2 Schottky heterojunctions have been prepared via a facile hydrothermal process. The properties of the heterojunction were fully characterized. The photocatalytic degradation performance of composites was examined by photo-degradation of tetracycline hydrochloride (TC-HCL) under visible light irradiation. Compared with single SnS2, 3% Ti3C2/SnS2 displayed the better performance, the removal rate of TC-HCL reached 87.7% and the kinetic rate constant (k) of the optimal 3% Ti3C2/SnS2 composite was about 2.7 times of that of bare SnS2. The improved photocatalytic activity of Ti3C2/SnS2 is ascribed to the formation of 2D/2D Schottky heterojunction, which promotes the spatial charge separation and increases the surface reactive sites.


Assuntos
Tetraciclina , Titânio , Antibacterianos , Catálise , Luz
20.
Adv Sci (Weinh) ; 9(7): e2104935, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35023300

RESUMO

Surgeons face challenges in intraoperatively defining margin of brain tumors due to its infiltrative nature. Extracellular acidosis caused by metabolic reprogramming of cancer cells is a reliable marker for tumor infiltrative regions. Although the acidic margin-guided surgery shows promise in improving surgical prognosis, its clinical transition is delayed by having the exogenous probes approved by the drug supervision authority. Here, an intelligent surface-enhanced Raman scattering (SERS) navigation system delineating glioma acidic margins without administration of exogenous probes is reported. With assistance of this system, the metabolites at the tumor cutting edges can be nondestructively transferred within a water droplet to a SERS chip with pH sensitivity. Homemade deep learning model automatically processes the Raman spectra collected from the SERS chip and delineates the pH map of tumor resection bed with increased speed. Acidity correlated cancer cell density and proliferation level are demonstrated in tumor cutting edges of animal models and excised tissues from glioma patients. The overall survival of animal models post the SERS system guided surgery is significantly increased in comparison to the conventional strategy used in clinical practice. This SERS system holds the promise in accelerating clinical transition of acidic margin-guided surgery for solid tumors with infiltrative nature.


Assuntos
Acidose , Neoplasias Encefálicas , Glioma , Animais , Neoplasias Encefálicas/cirurgia , Glioma/patologia , Glioma/cirurgia , Humanos , Margens de Excisão , Análise Espectral Raman
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