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1.
Sci Rep ; 14(1): 2488, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291121

RESUMO

Bladder cancer is one of the most common cancer types in the urinary system. Yet, current bladder cancer diagnosis and follow-up techniques are time-consuming, expensive, and invasive. In the clinical practice, the gold standard for diagnosis remains invasive biopsy followed by histopathological analysis. In recent years, costly diagnostic tests involving the use of bladder cancer biomarkers have been developed, however these tests have high false-positive and false-negative rates limiting their reliability. Hence, there is an urgent need for the development of cost-effective, and non-invasive novel diagnosis methods. To address this gap, here we propose a quick, cheap, and reliable diagnostic method. Our approach relies on an artificial intelligence (AI) model to analyze droplet patterns of blood and urine samples obtained from patients and comparing them to cancer-free control subjects. The AI-assisted model in this study uses a deep neural network, a ResNet network, pre-trained on ImageNet datasets. Recognition and classification of complex patterns formed by dried urine or blood droplets under different conditions resulted in cancer diagnosis with a high specificity and sensitivity. Our approach can be systematically applied across droplets, enabling comparisons to reveal shared spatial behaviors and underlying morphological patterns. Our results support the fact that AI-based models have a great potential for non-invasive and accurate diagnosis of malignancies, including bladder cancer.


Assuntos
Inteligência Artificial , Neoplasias da Bexiga Urinária , Humanos , Reprodutibilidade dos Testes , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Biomarcadores Tumorais/urina
3.
Redox Biol ; 53: 102319, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525027

RESUMO

Iron is an essential metal for cellular metabolism and signaling, but it has adverse effects in excess. The physiological consequences of iron deficiency are well established, yet the relationship between iron supplementation and pericellular oxygen levels in cultured cells and their downstream effects on metalloproteins has been less explored. This study exploits the metalloprotein geNOps in cultured HEK293T epithelial and EA.hy926 endothelial cells to test the iron-dependency in cells adapted to standard room air (18 kPa O2) or physiological normoxia (5 kPa O2). We show that cells in culture require iron supplementation to activate the metalloprotein geNOps and demonstrate for the first time that cells adapted to physiological normoxia require significantly lower iron compared to cells adapted to hyperoxia. This study establishes an essential role for recapitulating oxygen levels in vivo and uncovers a previously unrecognized requirement for ferrous iron supplementation under standard cell culture conditions to achieve geNOps functionality.


Assuntos
Técnicas Biossensoriais , Metaloproteínas , Células Endoteliais/metabolismo , Células HEK293 , Humanos , Ferro/metabolismo , Metaloproteínas/metabolismo , Óxido Nítrico/metabolismo , Oxigênio/metabolismo
4.
Commun Biol ; 5(1): 78, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35058555

RESUMO

DNA transfection is an important technology in life sciences, wherein nuclear entry of DNA is necessary to express exogenous DNA. Non-viral vectors and their transfection reagents are useful as safe transfection tools. However, they have no effect on the transfection of non-proliferating cells, the reason for which is not well understood. This study elucidates the mechanism through which transfected DNA enters the nucleus for gene expression. To monitor the behavior of transfected DNA, we introduce plasmid bearing lacO repeats and RFP-coding sequences into cells expressing GFP-LacI and observe plasmid behavior and RFP expression in living cells. RFP expression appears only after mitosis. Electron microscopy reveals that plasmids are wrapped with nuclear envelope (NE)‒like membranes or associated with chromosomes at telophase. The depletion of BAF, which is involved in NE reformation, delays plasmid RFP expression. These results suggest that transfected DNA is incorporated into the nucleus during NE reformation at telophase.


Assuntos
Núcleo Celular/fisiologia , DNA/genética , Regulação da Expressão Gênica/fisiologia , Proteínas de Membrana/metabolismo , Proteínas Nucleares/metabolismo , Plasmídeos/genética , Transporte Biológico , Linhagem Celular Tumoral , Humanos , Proteínas de Membrana/genética , Mutação , Proteínas Nucleares/genética , Análise de Célula Única , Telófase , Transfecção
5.
Sci Rep ; 9(1): 8461, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186495

RESUMO

Reformation of a functional nucleus at the end of mitosis is crucial for normal cellular activity. Reconstitution approaches using artificial beads in frog egg extracts have clarified the molecules required for nuclear formation in vitro. However, the spatiotemporal regulation of these components, which is required for the formation of a functional nucleus in living embryos, remains unknown. Here we demonstrate that exogenous DNA introduced in the form of DNA-conjugated beads induces the assembly of an artificial nucleus in living mouse cleavage-stage embryos. Live-cell imaging and immunofluorescence studies revealed that core histones and regulator of chromosome condensation 1 (RCC1) assembled on the DNA, suggesting that nucleosomes were formed. Electron microscopy showed that double-membrane structures, partly extended from annulate lamellae, formed around the beads. Nuclear pore complex-like structures indistinguishable from those of native nuclei were also formed, suggesting that this membranous structure resembled the normal nuclear envelope (NE). However, the reconstituted NE had no nuclear import activity, probably because of the absence of Ras-related nuclear protein (Ran). Thus, DNA is necessary for NE reassembly in mouse embryos but is insufficient to form a functional nucleus. This approach provides a new tool to examine factors of interest and their spatiotemporal regulation in nuclear formation.


Assuntos
Núcleo Celular/metabolismo , DNA/metabolismo , Microesferas , Zigoto/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Núcleo Celular/ultraestrutura , DNA/ultraestrutura , Feminino , Histonas/metabolismo , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos ICR , Microinjeções , Modelos Biológicos , Membrana Nuclear/metabolismo , Membrana Nuclear/ultraestrutura , Poro Nuclear/metabolismo , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura
6.
Genes Cells ; 24(5): 338-353, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30821042

RESUMO

Reassembly of the nuclear pore complex (NPC) at the end of mitosis is an important event for eukaryotic nuclear function. In this study, we examined the dynamic behaviors of the endoplasmic reticulum (ER) by "Live CLEM" imaging. In metaphase, numerous fenestrations on the ER membrane were observed around chromosomes. In telophase, these fenestrations became filled at the region attached to chromosomes, whereas they remained open at the region unattached to chromosomes, suggesting that NPC assembly takes place at fenestrations on the membrane. To determine the roles of nucleoporins in postmitotic NPC formation, we used artificial beads conjugated with anti-GFP antibody, which captures GFP-fused proteins on the beads when incorporated into cells. Live CLEM imaging of telophase cells containing Nup133-coated beads or Nup153-coated beads showed that Nup133 and Nup153, as the sole effector molecules, assembled the NPC-like structure on the membrane fenestrations. Indirect immunofluorescence staining of the Nup133-coated beads showed that Nup133 effectively assembled Nup107 and ELYS, whereas minimal assembly of Nup98 and Nup62 was observed; the Nup153-coated bead effectively assembled Nup98, Nup62 and Pom121, but assembled neither Nup107 nor ELYS. Our results suggest that Nup133 and Nup153 play different roles in assembling the NPC on membrane fenestrations.


Assuntos
Antígenos de Histocompatibilidade Menor/metabolismo , Mitose , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Poro Nuclear/metabolismo , Células HeLa , Humanos , Poro Nuclear/ultraestrutura , Ligação Proteica
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