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Objective To analyze the routine test parameter levels of patients with colorectal adenoma and colorectal cancer, and develop a prediction model. Methods A total of 580 patients diagnosed with colorectal adenoma (117 patients) and colorectal cancer (463 patients) were included in the retrospective study. The patients were randomly divided into two groups according to a 7:3 ratio: a training set with 406 cases and a validation set with 174 cases. Logistic regression analysis was used to establish a prediction model, and a nomogram was drawn. The model′s discrimination, calibration, and clinical applicability were evaluated using receiver operating characteristic curve (ROC), calibration plot, and decision curve analysis (DCA). Results Univariate logistic regression analysis identified 13 potential predictors: age, fecal occult blood test (FOBT), fibrinogen (FIB), thrombin time (TT), albumin (ALB), white blood cell value (WBC), neutrophil count (NEUT#), hematocrit value (HCT), mean corpuscular hemoglobin (MCH), red cell distribution width (RDW), platelet count (PLT), mean platelet volume (MPV), and activated partial thromboplastin time (APTT). Multivariate logistic regression analysis showed MPV, FIB, ALB, FOBT, TT, and HCT were risk factors for colorectal cancer in patients with colorectal adenoma (P<0.05). A nomogram was constructed based on these predictors to build a prediction model. The AUC of the ROC curve was 0.915 for colorectal cancer in the training set and 0.836 in the validation set. Calibration plots demonstrated high prediction accuracy and good model calibration. DCA results indicated the prediction model provided greater net benefit compared with the extreme models at threshold probabilities of approximately 55%-95%. Conclusion The developed prediction model exhibits satisfactory discrimination, calibration, and clinical applicability. The model can serve as an auxiliary tool in distinguishing between colorectal adenoma and colorectal cancer in patients.
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Connexin43 has been shown to play a pivotal role in wound healing process. Wound repair is enhanced by acute downregulation of connexin43, by increasing proliferation and migration of keratinocyte and fibroblast. Angiogenesis is also a central feature of wound repair, but little is known about the effects of connexin43 modulation on functions of endothelial cells. We used connexin43 specific small interference RNA (siRNA) to reduce the expression of connexin43 in human umbilical vein endothelial cell (HUVEC), and investigated the effects of connexin43 downregulation on intercellular communication, viability, proliferation, migration and angiogenic activity of HUVEC. Treatment of siRNA markedly reduced the expression of connexin43 by -80% in HUVEC (P < 0.05), and decreased the intercellular communication by -65% (P < 0.05). The viability, proliferation, migration and angiogenic activity of HUVEC decreased significantly (P < 0.05), compared with that of the normal cells. The results suggest that temporally downregulation of connexin43 expression at early stage of wound to inhibit the abnormal angiogenesis characterized with leaky and inflamed blood vessels, maybe a prerequisite for coordinated normal healing process.
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Robust and efficient control of therapeutic gene expression is needed for timing and dosing of gene therapy drugs in clinical applications. Ribozyme riboswitch provides a promising building block for ligand-controlled gene-regulatory system, based on its property that exhibits tunable gene regulation, design modularity, and target specificity. Ribozyme riboswitch can be used in various gene delivery vectors. In recent years, there have been breakthroughs in extending ribozyme riboswitch's application from gene-expression control to cellular function and fate control. High throughput screening platforms were established, that allow not only rapid optimization of ribozyme riboswitch in a microbial host, but also straightforward transfer of selected devices exhibiting desired activities to mammalian cell lines in a predictable manner. Mathematical models were employed successfully to explore the performance of ribozyme riboswitch quantitively and its rational design predictably. However, to progress toward gene therapy relevant applications, both precision rational design of regulatory circuits and the biocompatibility of regulatory ligand are still of crucial importance.
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Follicle-stimulating hormone (FSH) is a pituitary glycoprotein hormone that is essential for the development of ovarian follicles and testicular seminiferous tubules. The relatively short half-life of FSH in vivo requires daily injections for more than 10 days that is inconvenient and possibly contribute to the stress perceived by the patients. The goal of the present study was to increase FSH glycosylation, in order to develop a long-acting recombinant FSH. The cDNA of native alpha and beta subunit of human FSH was linked by a sequence with two N-linked glycosylation sites, and the resulted DNA was inserted into pcDNA3.1 vector to generate a recombinant vector of pcDNA3.1-FSH. The pcDNA3.1-FSH was linearized and transfected into CHO-K1, positive transformants were selected by G418 and confirmed by PCR and Western blotting. A single chain recombinant FSH was expressed, with molecular weight of about 49 kDa. The recombinant FSH expression level in CHO-K1 cell strain in serum-free culture was 3 mg/L. Single injection of this recombinant FSH could induce folliculogenesis and ovulation in rats, the efficacy was similar with the commercially available FSH preparation (Folltropin-V) administrated 8 times consecutively. The results suggested a long-acting FSH was produced successfully.
Assuntos
Animais , Cricetinae , Feminino , Humanos , Ratos , Células CHO , Cricetulus , Hormônio Foliculoestimulante Humano , Vetores Genéticos , Meia-Vida , Folículo Ovariano , Ovulação , Proteínas Recombinantes , TransfecçãoRESUMO
Aptamers are capable of binding a wide range of biomolecular targets with high affinity and specificity. It has been widely developed for diagnostic and therapeutic purposes. Because of unique three dimensional structures and cell-membrane penetration, aptamers inhibit virus infection not only through binding specific target, such as the viral envelope, genomic site, enzyme, or other viral components, but also can be connected to each other or with siRNA jointly achieve antiviral activity. Taking human immunodeficiency virus and hepatitis C virus as examples, this paper reviewed the effects and mechanisms of aptamers on disturbing viral infection and replication steps. It may provide an insight to the development of aptamer-based new antiviral drugs.
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Various artificial riboswitches have been constructed by utilization of designed aptamers or by modification of natural riboswitch systems, because they can regulate gene expression in a highly efficient, precise and fast way, and promise to supply simple cis-acting, modular, and non-immunogenic system for use in future gene therapy applications. In this review, we present an overview of currently available technologies to design and select engineered riboswitches, and discuss some possible technologies that would allow them highly responsive to non-natural ligands, and dynamic control of gene expression in mammalian cells. Though how to bring custom-designed riboswitches as a novel and versatile tool box to gene control system is still a great challenge, the combination of structure-activity relationship information, computer based molecular design, in vitro selection, and high-through screening will serve as powerful tools for further development of riboswitch based gene regulatory systems.