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1.
J Imaging Inform Med ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38977616

ABSTRACT

TumorPrism3D software was developed to segment brain tumors with a straightforward and user-friendly graphical interface applied to two- and three-dimensional brain magnetic resonance (MR) images. The MR images of 185 patients (103 males, 82 females) with glioblastoma multiforme were downloaded from The Cancer Imaging Archive (TCIA) to test the tumor segmentation performance of this software. Regions of interest (ROIs) corresponding to contrast-enhancing lesions, necrotic portions, and non-enhancing T2 high signal intensity components were segmented for each tumor. TumorPrism3D demonstrated high accuracy in segmenting all three tumor components in cases of glioblastoma multiforme. They achieved a better Dice similarity coefficient (DSC) ranging from 0.83 to 0.91 than 3DSlicer with a DSC ranging from 0.80 to 0.84 for the accuracy of segmented tumors. Comparative analysis with the widely used 3DSlicer software revealed TumorPrism3D to be approximately 37.4% faster in the segmentation process from initial contour drawing to final segmentation mask determination. The semi-automated nature of TumorPrism3D facilitates reproducible tumor segmentation at a rapid pace, offering the potential for quantitative analysis of tumor characteristics and artificial intelligence-assisted segmentation in brain MR imaging.

2.
J Korean Med Sci ; 39(5): e56, 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38317452

ABSTRACT

BACKGROUND: The acquisition of single-lead electrocardiogram (ECG) from mobile devices offers a more practical approach to arrhythmia detection. Using artificial intelligence for atrial fibrillation (AF) identification enhances screening efficiency. However, the potential of single-lead ECG for AF identification during normal sinus rhythm (NSR) remains under-explored. This study introduces a method to identify AF using single-lead mobile ECG during NSR. METHODS: We employed three deep learning models: recurrent neural network (RNN), long short-term memory (LSTM), and residual neural networks (ResNet50). From a dataset comprising 13,509 ECGs from 6,719 patients, 10,287 NSR ECGs from 5,170 patients were selected. Single-lead mobile ECGs underwent noise filtering and segmentation into 10-second intervals. A random under-sampling was applied to reduce bias from data imbalance. The final analysis involved 31,767 ECG segments, including 15,157 labeled as masked AF and 16,610 as Healthy. RESULTS: ResNet50 outperformed the other models, achieving a recall of 79.3%, precision of 65.8%, F1-score of 71.9%, accuracy of 70.5%, and an area under the receiver operating characteristic curve (AUC) of 0.79 in identifying AF from NSR ECGs. Comparative performance scores for RNN and LSTM were 0.75 and 0.74, respectively. In an external validation set, ResNet50 attained an F1-score of 64.1%, recall of 68.9%, precision of 60.0%, accuracy of 63.4%, and AUC of 0.68. CONCLUSION: The deep learning model using single-lead mobile ECG during NSR effectively identified AF at risk in future. However, further research is needed to enhance the performance of deep learning models for clinical application.


Subject(s)
Atrial Fibrillation , Deep Learning , Humans , Atrial Fibrillation/diagnosis , Artificial Intelligence , Neural Networks, Computer , Electrocardiography/methods
3.
Viruses ; 14(10)2022 09 30.
Article in English | MEDLINE | ID: mdl-36298724

ABSTRACT

Molecular therapies exploiting mRNA vectors embody enormous potential, as evidenced by the utility of this technology for the context of the COVID-19 pandemic. Nonetheless, broad implementation of these promising strategies has been restricted by the limited repertoires of delivery vehicles capable of mRNA transport. On this basis, we explored a strategy based on exploiting the well characterized entry biology of adenovirus. To this end, we studied an adenovirus-polylysine (AdpL) that embodied "piggyback" transport of the mRNA on the capsid exterior of adenovirus. We hypothesized that the efficient steps of Ad binding, receptor-mediated entry, and capsid-mediated endosome escape could provide an effective pathway for transport of mRNA to the cellular cytosol for transgene expression. Our studies confirmed that AdpL could mediate effective gene transfer of mRNA vectors in vitro and in vivo. Facets of this method may offer key utilities to actualize the promise of mRNA-based therapeutics.


Subject(s)
Adenoviridae Infections , COVID-19 , Humans , Adenoviridae/genetics , Genetic Vectors/genetics , Gene Transfer Techniques , Polylysine , RNA, Messenger/genetics , RNA, Messenger/metabolism , Pandemics , Capsid Proteins/genetics , Capsid Proteins/metabolism , Biology
4.
J Control Release ; 334: 106-113, 2021 06 10.
Article in English | MEDLINE | ID: mdl-33872627

ABSTRACT

For the developing field of gene therapy the successful address of the basic requirement effective gene delivery has remained a critical barrier. In this regard, the "Holy Grail" vector envisioned by the field's pioneers embodied the ability to achieve efficient and specific in vivo gene delivery. Functional linkage of antibody selectivity with viral vector efficiency represented a logical strategy but has been elusive. Here we have addressed this key issue by developing the technical means to pair antibody-based targeting with adenoviral-mediated gene transfer. Our novel method allows efficient and specific gene delivery. Importantly, our studies validated the achievement of this key vectorology mandate in the context of in vivo gene delivery. Vectors capable of effective in vivo delivery embody the potential to dramatically expand the range of successful gene therapy cures.


Subject(s)
Adenoviridae , Single-Domain Antibodies , Adenoviridae/genetics , Gene Transfer Techniques , Genetic Engineering , Genetic Therapy , Genetic Vectors , Single-Domain Antibodies/genetics
5.
Mol Cancer Ther ; 19(3): 966-971, 2020 03.
Article in English | MEDLINE | ID: mdl-31907220

ABSTRACT

The application of cancer gene therapy has heretofore been restricted to local, or locoregional, neoplastic disease contexts. This is owing to the lack of gene transfer vectors, which embody the requisite target cell selectivity in vivo required for metastatic disease applications. To this end, we have explored novel vector engineering paradigms to adapt adenovirus for this purpose. Our novel strategy exploits three distinct targeting modalities that operate in functional synergy. Transcriptional targeting is achieved via the hROBO4 promoter, which restricts transgene expression to proliferative vascular endothelium. Viral binding is modified by incorporation of an RGD4C peptide in the HI loop of the fiber knob for recognition of cellular integrins. Liver sequestration is mitigated by ablation of factor X binding to the major capsid protein hexon by a serotype swap approach. The combination of these technologies into the context of a single-vector agent represents a highly original approach. Studies in a murine model of disseminated cancer validated the in vivo target cell selectivity of our vector agent. Of note, clear gains in therapeutic index accrued these vector modifications. Whereas there is universal recognition of the value of vector targeting, very few reports have validated its direct utility in the context of cancer gene therapy. In this regard, our article validates the direct gains that may accrue these methods in the stringent delivery context of disseminated neoplastic disease. Efforts to improve vector targeting thus represent a critical direction to fully realize the promise of cancer gene therapy.


Subject(s)
Adenoviridae/genetics , Biomarkers, Tumor/genetics , Capsid Proteins/genetics , Genetic Therapy , Genetic Vectors/administration & dosage , Kidney Neoplasms/therapy , Neovascularization, Pathologic/therapy , Animals , Apoptosis , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Kidney Neoplasms/blood supply , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Mice , Mice, Inbred NOD , Mice, SCID , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Promoter Regions, Genetic , Receptors, Cell Surface/genetics , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
6.
Exp Mol Med ; 51(9): 1-15, 2019 09 27.
Article in English | MEDLINE | ID: mdl-31562296

ABSTRACT

Increased endothelial permeability, one of the earliest signs of endothelial dysfunction, is associated with the development of cardiovascular diseases such as hypertension and atherosclerosis. Recent studies suggest that the receptor for advanced glycation end products (RAGE) regulates endothelial permeability in inflammation. In the present study, we investigated the regulatory mechanism of RAGE in endothelial hyperpermeability induced by angiotensin II (Ang II), a well-known inflammatory mediator, and the potential therapeutic effect of soluble RAGE (sRAGE), a decoy receptor for RAGE ligands. For in vitro studies, Ang II-treated human umbilical vein endothelial cells (HUVECs) were treated with siRNA specific to either RAGE or sRAGE to disrupt RAGE-mediated signaling. Endothelial permeability was estimated using FITC-labeled dextran 40 and a resistance meter. To evaluate intercellular junction disruption, VE-cadherin expression was examined by western blotting and immunocytochemistry. Ang II increased the expression of the Ang II type 1 receptor (AT1R) and RAGE, and this increase was inhibited by sRAGE. sRAGE prevented Ang II-induced VE-cadherin disruption in HUVECs. For in vivo studies, Ang II-infused, atherosclerosis-prone apolipoprotein E knockout mice were utilized. Endothelial permeability was assessed by Evans blue staining of the aorta. Ang II increased endothelial barrier permeability, and this effect was significantly attenuated by sRAGE. Our data demonstrate that blockade of RAGE signaling using sRAGE attenuates Ang II-induced endothelial barrier permeability in vitro and in vivo and indicate the therapeutic potential of sRAGE in controlling vascular permeability under pathological conditions.


Subject(s)
Antigens, Neoplasm/genetics , Cardiovascular Diseases/genetics , HMGB1 Protein/genetics , Mitogen-Activated Protein Kinases/genetics , Receptor, Angiotensin, Type 1/genetics , Angiotensin II/genetics , Animals , Antigens, CD/genetics , Aorta/metabolism , Aorta/pathology , Atherosclerosis/genetics , Atherosclerosis/pathology , Cadherins/genetics , Capillary Permeability/genetics , Cardiovascular Diseases/pathology , Endothelial Cells/metabolism , Endothelial Cells/pathology , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Hypertension/genetics , Hypertension/pathology , Inflammation/genetics , Inflammation/pathology , Ligands , Mice , Mice, Knockout , RNA, Small Interfering/genetics , Signal Transduction/genetics
7.
Article in English | MEDLINE | ID: mdl-29891600

ABSTRACT

Morbidity and mortality resulting from influenza-like disease are a threat, especially for older adults. To improve case management, next-generation broad-spectrum antiviral therapeutics that are efficacious against major drivers of influenza-like disease, including influenza viruses and respiratory syncytial virus (RSV), are urgently needed. Using a dual-pathogen high-throughput screening protocol for influenza A virus (IAV) and RSV inhibitors, we have identified N4-hydroxycytidine (NHC) as a potent inhibitor of RSV, influenza B viruses, and IAVs of human, avian, and swine origins. Biochemical in vitro polymerase assays and viral RNA sequencing revealed that the ribonucleotide analog is incorporated into nascent viral RNAs in place of cytidine, increasing the frequency of viral mutagenesis. Viral passaging in cell culture in the presence of an inhibitor did not induce robust resistance. Pharmacokinetic profiling demonstrated dose-dependent oral bioavailability of 36 to 56%, sustained levels of the active 5'-triphosphate anabolite in primary human airway cells and mouse lung tissue, and good tolerability after extended dosing at 800 mg/kg of body weight/day. The compound was orally efficacious against RSV and both seasonal and highly pathogenic avian IAVs in mouse models, reducing lung virus loads and alleviating disease biomarkers. Oral dosing reduced IAV burdens in a guinea pig transmission model and suppressed virus spread to uninfected contact animals through direct transmission. Based on its broad-spectrum efficacy and pharmacokinetic properties, NHC is a promising candidate for future clinical development as a treatment option for influenza-like diseases.


Subject(s)
Antiviral Agents/pharmacology , Respiratory Syncytial Virus, Human/drug effects , Animals , Cells, Cultured , Guinea Pigs , Humans , Influenza A virus/drug effects , Influenza A virus/genetics , Influenza B virus/drug effects , Influenza B virus/genetics , Mice , RNA, Viral/genetics , Respiratory Syncytial Virus, Human/genetics , Respiratory Syncytial Viruses/drug effects , Respiratory Syncytial Viruses/genetics
8.
Eur J Med Chem ; 140: 65-73, 2017 Nov 10.
Article in English | MEDLINE | ID: mdl-28923387

ABSTRACT

Upon high-throughput screening of synthetic small molecule libraries with the infectious hepatitis C virus (HCV) cell culture system, we identified an iminodipyridinopyrimidine (IDPP) scaffold. IDPP did not inhibit HCV replication, but exhibited very potent inhibitory activity on early and late steps of HCV life cycle. Applying an intensive structure-activity relationship (SAR) study, a promising IDPP Lead compound (12c) with excellent potency (EC50 = 10 nM), high safety margin (SI > 2000), and an acceptable stability in human and rat liver microsomes (t1/2 >60 min) was identified. Overall, our results suggest that the IDPP scaffold could be used for the development of novel HCV interventions.


Subject(s)
Antiviral Agents/pharmacology , Hepacivirus/drug effects , Heterocyclic Compounds, 3-Ring/pharmacology , Animals , Antiviral Agents/chemical synthesis , Antiviral Agents/chemistry , Cells, Cultured , Dose-Response Relationship, Drug , Female , Heterocyclic Compounds, 3-Ring/chemical synthesis , Heterocyclic Compounds, 3-Ring/chemistry , Humans , Male , Microbial Sensitivity Tests , Molecular Structure , Rats , Structure-Activity Relationship , Virus Replication/drug effects
9.
Korean J Radiol ; 18(3): 498-509, 2017.
Article in English | MEDLINE | ID: mdl-28458602

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the reliability and quality of radiomic features in glioblastoma multiforme (GBM) derived from tumor volumes obtained with semi-automated tumor segmentation software. MATERIALS AND METHODS: MR images of 45 GBM patients (29 males, 16 females) were downloaded from The Cancer Imaging Archive, in which post-contrast T1-weighted imaging and fluid-attenuated inversion recovery MR sequences were used. Two raters independently segmented the tumors using two semi-automated segmentation tools (TumorPrism3D and 3D Slicer). Regions of interest corresponding to contrast-enhancing lesion, necrotic portions, and non-enhancing T2 high signal intensity component were segmented for each tumor. A total of 180 imaging features were extracted, and their quality was evaluated in terms of stability, normalized dynamic range (NDR), and redundancy, using intra-class correlation coefficients, cluster consensus, and Rand Statistic. RESULTS: Our study results showed that most of the radiomic features in GBM were highly stable. Over 90% of 180 features showed good stability (intra-class correlation coefficient [ICC] ≥ 0.8), whereas only 7 features were of poor stability (ICC < 0.5). Most first order statistics and morphometric features showed moderate-to-high NDR (4 > NDR ≥1), while above 35% of the texture features showed poor NDR (< 1). Features were shown to cluster into only 5 groups, indicating that they were highly redundant. CONCLUSION: The use of semi-automated software tools provided sufficiently reliable tumor segmentation and feature stability; thus helping to overcome the inherent inter-rater and intra-rater variability of user intervention. However, certain aspects of feature quality, including NDR and redundancy, need to be assessed for determination of representative signature features before further development of radiomics.


Subject(s)
Glioblastoma/diagnosis , Software , Adult , Aged , Automation , Female , Glioblastoma/diagnostic imaging , Glioblastoma/pathology , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged
10.
Sci Rep ; 7: 44676, 2017 03 23.
Article in English | MEDLINE | ID: mdl-28333153

ABSTRACT

Despite recent advances in curing chronic hepatitis C (CHC), the high economic burden to therapy, viral drug resistance, difficult to treat hepatitis C virus (HCV) genotypes and patient groups are still of concern. To address this unmet medical needs, we devised strategies to identify novel viral interventions through target-free high-throughput screening of small molecules utilizing a phenotypic-based HCV infection assay. Thereby, a very potent (EC50 46 ± 26 pM) iminodipyridinopyrimidine (IDPP) drug candidate was selected, and confirmed in primary human hepatocytes (EC50 0.5 nM). IDPP mainly targets a post-attachment step of HCV without affecting endosomal acidification, prevents the secretion of infectious particles and viral cell-to-cell spread. The putative molecular target of IDPP is glycoprotein E1, as revealed by selection for viral drug resistance (Gly-257-Arg). IDPP was synergistic in combination with FDA-approved HCV drugs and inhibited pre-existing resistant HCV strains induced by today's therapies. Interestingly, IDPP exclusively inhibited HCV genotype 2. However, we identified the genotype-specificity determining region in E1 and generated HCV genotype 1 susceptible to IDPP by changing one amino acid in E1 (Gln-257-Gly). Together, our results indicate an opportunity to provide an alternative treatment option for CHC and will shed light on the poorly understood function of HCV glycoprotein E1.


Subject(s)
Antiviral Agents/pharmacology , Hepacivirus/drug effects , Pyridines/pharmacology , Pyrimidines/pharmacology , Viral Envelope Proteins/antagonists & inhibitors , Virus Internalization/drug effects , Virus Release/drug effects , Amino Acid Substitution , Antiviral Agents/chemical synthesis , Carbamates , Drug Combinations , Drug Discovery , Drug Resistance, Viral/drug effects , Drug Resistance, Viral/genetics , Drug Synergism , Gene Expression , Hepacivirus/genetics , Hepacivirus/metabolism , Hepatocytes/virology , High-Throughput Screening Assays , Host-Pathogen Interactions , Humans , Imidazoles/pharmacology , Interferon-alpha/pharmacology , Oligopeptides/pharmacology , Primary Cell Culture , Pyridines/chemical synthesis , Pyrimidines/chemical synthesis , Pyrrolidines , Sofosbuvir/pharmacology , Valine/analogs & derivatives , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism , Virion/drug effects , Virion/genetics , Virion/metabolism
11.
Antiviral Res ; 132: 287-95, 2016 08.
Article in English | MEDLINE | ID: mdl-27387825

ABSTRACT

Hepatitis C virus (HCV) is considered a major public health concern worldwide. Despite recent advances in curing chronic hepatitis C, unmet medical needs still remain, especially due to the high economic burden of therapies. Accordingly, our study aimed to identify affordable novel HCV inhibitors by screening of natural product compound libraries. We identified micrococcin P1, a macrocyclic peptide antibiotic, inhibiting HCV entry in a pan-genotypic manner with an EC50 range of 0.1-0.5 µM. Micrococcin P1 interfered with HCV entry at an attachment step. Furthermore, micrococcin P1 efficiently inhibited HCV spread by blocking cell-free infection as well as cell-to-cell transmission, without affecting the secretion of infectious virions. Interestingly, the putative molecular target of micrococcin P1 is glycoprotein E2 (IIe-630-Thr), as revealed by selection for viral drug resistance. In addition, micrococcin P1 inhibited sofosbuvir-resistant HCV strains and showed synergy in combination with selected HCV drugs, suggesting an alternative treatment paradigm for patients. In conclusion, we identified micrococcin P1 as specifically inhibiting entry of all HCV genotypes and demonstrated that micrococcin P1 potentially could add value to therapies in combination with current HCV interventions.


Subject(s)
Antiviral Agents/pharmacology , Bacteriocins/pharmacology , Genotype , Hepacivirus/drug effects , Hepacivirus/physiology , Peptides/pharmacology , Virus Internalization/drug effects , Antiviral Agents/chemistry , Bacteriocins/chemistry , Cell Line , Cells, Cultured , Dose-Response Relationship, Drug , Drug Resistance, Viral/drug effects , Drug Synergism , Hepatitis C/drug therapy , Hepatitis C/virology , Humans , Peptides/chemistry , Virus Release/drug effects , Virus Replication/drug effects
12.
Br J Pharmacol ; 173(1): 191-211, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26445091

ABSTRACT

BACKGROUND AND PURPOSE: Hepatitis C virus (HCV) infection is responsible for various chronic inflammatory liver diseases. Here, we have identified a naturally occurring compound with anti-HCV activity and have elucidated its mode of antiviral action. EXPERIMENTAL APPROACH: Luciferase reporter and real-time RT-PCR assays were used to measure HCV replication. Western blot, fluorescence-labelled HCV replicons and infectious clones were employed to quantitate expression levels of viral proteins. Resistant HCV mutant mapping, in vitro NS3 protease, helicase, NS5B polymerase and drug affinity responsive target stability assays were also used to study the antiviral mechanism. KEY RESULTS: A resveratrol tetramer, vitisin B from grapevine root extract showed high potency against HCV replication (EC50 = 6 nM) with relatively low cytotoxicity (EC50 >10 µM). Combined treatment of vitisin B with an NS5B polymerase inhibitor (sofosbuvir) exhibited a synergistic or at least additive antiviral activity. Analysis of a number of vitisin B-resistant HCV variants suggested an NS3 helicase as its potential target. We confirmed a direct binding between vitisin B and a purified NS3 helicase in vitro. Vitisin B was a potent inhibitor of a HCV NS3 helicase (IC50 = 3 nM). In vivo, Finally, we observed a preferred tissue distribution of vitisin B in the liver after i.p. injection in rats, at clinically attainable concentrations. Conclusion and Implications Vitisin B is one of the most potent HCV helicase inhibitors identified so far. Vitisin B is thus a prime candidate to be developed as the first HCV drug derived from natural products.


Subject(s)
Benzofurans/chemistry , Benzofurans/pharmacology , Hepacivirus/enzymology , Phenols/chemistry , Phenols/pharmacology , RNA Helicases/antagonists & inhibitors , Stilbenes/chemistry , Stilbenes/pharmacology , Viral Nonstructural Proteins/antagonists & inhibitors , Animals , Benzofurans/pharmacokinetics , Biological Products/chemistry , Biological Products/pharmacokinetics , Biological Products/pharmacology , Cell Line , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Synergism , Flavonoids , Hepacivirus/drug effects , Humans , Phenols/pharmacokinetics , Protein Binding , RNA Helicases/metabolism , Rats , Resveratrol , Sofosbuvir/pharmacology , Stilbenes/pharmacokinetics , Tissue Distribution , Viral Nonstructural Proteins/metabolism , Virus Replication/drug effects
13.
Comput Biol Med ; 42(5): 523-37, 2012 May.
Article in English | MEDLINE | ID: mdl-22402196

ABSTRACT

In this paper, we present a new segmentation method using the level set framework for medical volume images. The method was implemented using the surface evolution principle based on the geometric deformable model and the level set theory. And, the speed function in the level set approach consists of a hybrid combination of three integral measures derived from the calculus of variation principle. The terms are defined as robust alignment, active region, and smoothing. These terms can help to obtain the precise surface of the target object and prevent the boundary leakage problem. The proposed method has been tested on synthetic and various medical volume images with normal tissue and tumor regions in order to evaluate its performance on visual and quantitative data. The quantitative validation of the proposed segmentation is shown with higher Jaccard's measure score (72.52%-94.17%) and lower Hausdorff distance (1.2654 mm-3.1527 mm) than the other methods such as mean speed (67.67%-93.36% and 1.3361mm-3.4463 mm), mean-variance speed (63.44%-94.72% and 1.3361 mm-3.4616 mm), and edge-based speed (0.76%-42.44% and 3.8010 mm-6.5389 mm). The experimental results confirm that the effectiveness and performance of our method is excellent compared with traditional approaches.


Subject(s)
Models, Anatomic , Brain Neoplasms/diagnosis , Humans , Reproducibility of Results
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