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关键词： artificial intelligence   deep learning   machine learning   parotid gland tumors   radiomics  

摘要： Purpose of review Advances in computer technology and growing expectations from computer-aided systems have led to the evolution of artificial intelligence into subsets, such as deep learning and radiomics, and the use of these systems is revolutionizing modern radiological diagnosis. In this review, artificial intelligence applications developed with radiomics and deep learning methods in the differential diagnosis of parotid gland tumors (PGTs) will be overviewed. Recent findings The development of artificial intelligence models has opened new scenarios owing to the possibility of assessing features of medical images that usually are not evaluated by physicians. Radiomics and deep learning models come to the forefront in computer-aided diagnosis of medical images, even though their applications in the differential diagnosis of PGTs have been limited because of the scarcity of data sets related to these rare neoplasms. Nevertheless, recent studies have shown that artificial intelligence tools can classify common PGTs with reasonable accuracy. All studies aimed at the differential diagnosis of benign vs. malignant PGTs or the identification of the commonest PGT subtypes were identified, and five studies were found that focused on deep learning-based differential diagnosis of PGTs. Data sets were created in three of these studies with MRI and in two with computed tomography (CT). Additional seven studies were related to radiomics. Of these, four were on MRI-based radiomics, two on CT-based radiomics, and one compared MRI and CT-based radiomics in the same patients.

关键词： Alzheimer's Disease   Tau   Diffusion MRI   Structural connectivity   Network metrics   Neurocognitive tests  

摘要： Tau neurofibrillary tangles have a central role in the pathogenesis of Alzheimer's Disease (AD). Mounting evidence indicates that the propagation of tau is assisted by brain connectivity with weakened white-matter integrity along the propagation pathways. Recent advances in tau positron emission tomography tracers and diffusion magnetic resonance imaging allow the visualization of tau pathology and white-matter connectivity of the brain in vivo. The current study aims to investigate how tau deposition and structural connectivity are associated with memory function in prodromal AD. In this study, tau accumulation and structural connectivity data from 83 individuals (57 cognitively normal participants and 26 participants with mild cognitive impairment) were associated with neurocognitive test scores. Statistical analyses were performed in 70 cortical/subcortical brain regions to determine: 1. the level of association between tau and network metrics extracted from structural connectivity and 2. the association patterns of brain memory function with tau accumulation and network metrics. The results showed that tau accumulation and network metrics were correlated in early tau deposition regions. Furthermore, tau accumulation was associated with worse performance in almost all neurocognitive tests performance evaluated in the study. In comparison, decreased network connectivity was associated with declines in the delayed memory recall in Craft Stories and Benson Figure Copy. Interaction analysis indicates that tau deposition and dysconnectivity have a synergistic effect on the delayed Benson Figure Recall. Overall, our findings indicate that both tau deposition and structural dysconnectivity are associated with neurocognitive dysfunction. They also suggest that tau-PET may have better sensitivity to neurocognitive performance than diffusion MRI-derived measures of white-matter connectivity.

关键词： Batteries   State of charge   Current control   Computer architecture   Voltage control   Microprocessors   Transfer functions   Active balancing   battery management systems (BMSs)   battery power modules (BPMs)   current regulation   current sharing   differential current control   small-signal analysis   state-of-charge (SOC) control  

摘要： Parallel output connected converters have been widely investigated with a focus on equal current and power sharing. However, parallel output connected battery power modules (BPMs) require unequal currents to enable state-of-charge (SOC) control in active battery management systems (BMS.) This article presents simple differential input current regulation for SOC control. Compared with equal current sharing, differential current regulation is more critical on the system stability due to the cross-coupling between the paralleled BPMs. The article proposes design guidelines that enable differential current control while considering the cross-coupling between the paralleled BPMs. The small-signal model of a battery brick consisting of N parallel output connected BPMs that operate in boost mode is presented. This article shows the effect of paralleling and differential currents on the individual input current regulation loops. Simulations and experiments verify the analysis. Experimental validation using a 300-W prototype consisting of three parallel output connected battery modules in an active BMS is presented.

关键词： Nonlinear fractional differential equation   Generalized non-expansive mappings   Weak contraction   F iterative scheme   Fixed point   Banach spaces   Almost G-stability  

摘要： In this paper, we prove thatFiterative scheme is almost stable for weak contractions. Further, we prove convergence results for weak contractions as well as for generalized non-expansive mappings due to Hardy and Rogers viaFiterative scheme. We also prove thatFiterative scheme converges faster than the some known iterative schemes for weak contractions. An illuminative numerical example is formulated to support our assertion. Finally, utilizing our main result the solution of nonlinear fractional differential equation is approximated.

关键词： COVID-19   monocytes/M phi s   MS4A3   MS4A4A   MS4A6A   rheumatoid arthritis  

摘要： The MS4A gene family encodes 18 tetraspanin-like proteins, most of which with unknown function. MS4A1 (CD20), MS4A2 (Fc epsilon RI beta), MS4A3 (HTm4), and MS4A4A play important roles in immunity, whereas expression and function of other members of the family are unknown. The present investigation was designed to obtain an expression fingerprint of MS4A family members, using bioinformatics analysis of public databases, RT-PCR, and protein analysis when possible. MS4A3, MS4A4A, MS4A4E, MS4A6A, MS4A7, and MS4A14 were expressed by myeloid cells. MS4A6A and MS4A14 were expressed in circulating monocytes and decreased during monocyte-to-M phi differentiation in parallel with an increase in MS4A4A expression. Analysis of gene expression regulation revealed a strong induction of MS4A4A, MS4A6A, MS4A7, and MS4A4E by glucocorticoid hormones. Consistently with in vitro findings, MS4A4A and MS4A7 were expressed in tissue M phi s from COVID-19 and rheumatoid arthritis patients. Interestingly, MS4A3, selectively expressed in myeloid precursors, was found to be a marker of immature circulating neutrophils, a cellular population associated to COVID-19 severe disease. The results reported here show that members of the MS4A family are differentially expressed and regulated during myelomonocytic differentiation, and call for assessment of their functional role and value as therapeutic targets.

关键词： automated disease diagnosis   beta thalassemia   differential diagnosis   iron deficiency anemia   iterative Chi2 selector   machine learning  

摘要： Introduction The differential diagnosis of anemia is an important issue for hematology laboratories. We aimed at investigating the performance of a powerful computer-based model to aid diagnosis. Materials and methods Our work presents a new feature selection-based automated disease diagnosis model. To create a testbed, a new corpus is collected retrospectively. Our data sets contain beta thalassemia trait, iron deficiency anemia, and healthy groups. Our presented automated ailment classification model consists iterative chi2 (IChi2) feature selection and classification phases. The used data set includes 25 features, and IChi2 selects the 20 most valuable of them. These are forwarded to 24 traditional classifiers. Results In this work, two data sets have been used to test our proposal. In the classification phase of this model, 24 shallow classifiers have been used and the best accurate classifiers are Medium Gaussian Support Vector Machine (MGSVM) and Coarse Tree (CT) for the first and second data sets, respectively. These classifiers have been attained 97.48% and 99.73% classification accuracies using the first and second data sets, consecutively. These results are calculated using 10-fold cross-validation. Moreover, hold-out validation has been used in this work, and the results are given in the experiments. Conclusion Our results denoted the success of IChi2-based classification model for diagnosis on the laboratory data set. We have found a new and robust model to differentiate iron deficiency anemia and beta thalassemia trait. This model may be beneficial for rational laboratory use.

关键词： Sevoflurane   Sensitivity   Single nucleotide polymorphism   Whole exome sequencing   Genome-wide association study  

摘要： Background: The anesthesia sensitivity is heterogeneous both in animals and humans, while the underlying molecular mechanism has not yet been determined. Here, for the first time, we conducted a prospective observational study to test whether genetic variations contribute to the differential sensitivity to sevoflurane in humans. Methods: Five hundred patients who underwent abdominal surgeries were included. The end-tidal sevoflurane concentration (ETsevo) was adjusted to maintain Bispectral index (BIS) value between 40 and 60. The mean ETsevo from 20 min after endotracheal intubation to 2 h after the beginning of surgery was calculated for each patient. These patients were further divided into high sensitivity group (mean - SD, H group) and low sensitivity group (mean + SD, L group) to investigate the genetic variants related to the differential sensitivity to sevoflurane by whole-exome sequencing (WES) and genome-wide association study (GWAS) in karyocyte from peripheral blood. Results: The mean ETsevo of these 500 patients was 1.60% +/- 0.34%. After pairing, 55 patients from H group and 59 patients from L group were selected for WES (ETsevo of H group: 1.06% +/- 0.13% vs. ETsevo of L group: 2.17% +/- 0.16%, P < 0.001), respectively. Finally, FAT atypical cadherin 2 (FAT2, SNP rs174272, rs174271, and rs174261), acireductone dioxygenase 1 (ADI1, SNP rs117278), NEDD4 E3 ubiquitin protein ligase (NEDD4, SNP rs70048, rs70049, and rs70056), and FAD dependent oxidoreductase domain containing 2 (FOXRED2, SNP rs144281) were found to be associated with sevoflurane sensitivity. Conclusions: Genetic variations may contribute to the differential sensitivity to sevoflurane among humans.

关键词： Immune evasion   Renal cell carcinoma   Medicine/Public Health   general   Pathology   Laboratory Medicine  

摘要： Through analysis of the PD-L1 promoter, the authors describe two clear cell renal cell carcinoma (ccRCC) models that exhibit differential PD-L1 expression levels upon IFN gamma and hypoxia stimulation. Mutant-VHL ccRCC cells display higher PD-L1 expression than wild-type-VHL ccRCC cells due to high basal HIF2 alpha expression and a stronger response to IFN gamma stimulation. Thus, mutant-VHL ccRCC cells are expected to respond well to immune checkpoint inhibitors. Programmed death-ligand 1 (PD-L1) is constitutively expressed by hypoxia-inducible factor 2 alpha (HIF2 alpha). It can be induced by interferon gamma (IFN gamma) signaling in clear cell renal cell carcinoma (ccRCC). Clinical trials of metastatic ccRCCs have suggested that a canonical IFN gamma signature is a better biomarker for therapeutic response to immune checkpoint inhibitors (ICIs) than PD-L1 expression levels in tumor cells. To understand the therapeutic response to ICIs according to PD-L1 expression levels, we analyzed transcriptional regulation of the PD-L1 promoter by HIF2 alpha and IFN gamma-inducible interferon regulatory factor-1 (IRF-1) in ccRCC cells. Here, we present two ccRCC cell models showing differential PD-L1 expression levels in response to IFN gamma and hypoxia. Analysis of The Cancer Genome Atlas RNA-sequencing data revealed that PD-L1 expression correlated with JAK2 and STAT1 expression of the canonical IFN gamma signature in ccRCC tissues. Upon IFN gamma stimulation, PD-L1 was induced by sequential activation of JAK2/STAT1/IRF-1 signaling in both WT- and Mut- VHL ccRCC cells. IFN gamma activated the IRF-1 alpha site of the PD-L1 promoter. The IFN gamma-mediated increase of PD-L1 expression in Mut-VHL cells was 4.8-fold greater than that in WT-VHL cells. Under normoxia condition, PD-L1 expression in Mut-VHL cells was significantly higher than that in WT-VHL cells due to high basal HIF2 alpha expression. Under hypoxia condition, PD-L1 expression in WT-VHL cells was induced up to 1.

关键词： Acute myeloid leukaemia   Oncogenes   Medicine/Public Health   general   Internal Medicine   Intensive / Critical Care Medicine   Cancer Research   Oncology   Hematology  

摘要： The Switch/Sugar Non-Fermenting (SWI/SNF) nucleosome remodeling complexes play important roles in normal development and in the development of various cancers. Core subunits of the SWI/SNF complexes have been shown to have oncogenic roles in acute myeloid leukemia. However, the roles of the unique targeting subunits, including that of Arid2 and Arid1b, in AML leukemogenesis are not well understood. Here, we used conditional knockout mouse models to elucidate their role in MLL-AF9 leukemogenesis. We uncovered that Arid2 has dual roles;enhancing leukemogenesis when deleted during leukemia initiation and yet is required during leukemia maintenance. Whereas, deleting Arid1b in either phase promotes leukemogenesis. Our integrated analyses of transcriptomics and genomic binding data showed that, globally, Arid2 and Arid1b regulate largely distinct sets of genes at different disease stages, respectively, and in comparison, to each other. Amongst the most highly dysregulated transcription factors upon their loss, Arid2 and Arid1b converged on the regulation of Etv4/Etv5, albeit in an opposing manner while also regulating distinct TFs including Gata2,Tcf4, Six4, Irf4 and Hmgn3. Our data demonstrate the differential roles of SWI/SNF subunits in AML leukemogenesis and emphasize that cellular context and disease stage are key in determining their functions during this process.