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Background: Isoleucinyl‐tRNA synthetase (IARS) is encoded by the IARS1 gene and catalyzes the binding of isoleucine to specific tRNA. Objective: This study aims to investigate the pathogenicity of novel IARS1 variants and the genotype–phenotype association, in order to expand the spectrum of pathogenic variants and phenotypes of IARS1‐related disease and provide new evidence for the phenotypic spectrum of IARS1 variants. Methods: Clinical data of the proband were collected, and trio whole‐exome sequencing (WES) was performed on the proband and the parents. Candidate variants were validated using Sanger sequencing. Bioinformatics software was utilized to analyze the functional consequences of identified variants and predict their potential deleteriousness. Results: A 17‐month‐old female patient presented with microcephaly, left external ear malformation, decreased muscle strength and tone in all limbs, epileptic seizures, global developmental delay, and developmental regression. Trio WES identified compound heterozygous variants in the IARS1 gene, c.120‐1G>A and c.2164C>A, which were novel pathogenic and likely pathogenic variants, respectively. The phenotype of developmental regression has not been reported before. Only one patient with IARS1 compound heterozygous variants has been reported in the world to have an epileptic phenotype, and this is the second patient with an epileptic phenotype. Bioinformatics analysis revealed that the splicing variant disrupted the canonical splice donor site, while the missense variant altered the local electrostatics of the IARS1 protein surface, potentially leading to functional abnormalities. Conclusion: This study identified novel IARS1 variants and the phenotype of developmental regression, expanding the spectrum of pathogenic variants and phenotypes of IARS1‐related diseases and providing new evidence for the rare phenotype of epileptic seizures caused by IARS1 variants. [ABSTRACT FROM AUTHOR]

Background The association between different phenotypes and genotypes of circulating tumor cells (CTCs) and efficacy of neoadjuvant chemotherapy (NAC) remains uncertain. This study was conducted to evaluate the relationship of FTH1 gene-associated CTCs (F-CTC) with/without epithelial-mesenchymal transition (EMT) markers, or their dynamic changes with the efficacy of NAC in patients with non-metastatic breast cancer. Patients and Methods This study enrolled 120 patients with non-metastatic breast cancer who planned to undergo NAC. The FTH1 gene and EMT markers in CTCs were detected before NAC (T0), after 2 cycles of chemotherapy (T1), and before surgery (T2). The associations of these different types of CTCs with rates of pathological complete response (pCR) and breast-conserving surgery (BCS) were evaluated using the binary logistic regression analysis. Results F-CTC in peripheral blood ≥1 at T0 was an independent factor for pCR rate in patients with HER2-positive (odds ratio [OR]=0.08, 95% confidence interval [CI], 0.01-0.98, P =.048). The reduction in the number of F-CTC at T2 was an independent factor for BCS rate (OR = 4.54, 95% CI, 1.14-18.08, P =.03). Conclusions The number of F-CTC prior to NAC was related to poor response to NAC. Monitoring of F-CTC may help clinicians formulate personalized NAC regimens and implement BCS for patients with non-metastatic breast cancer. [ABSTRACT FROM AUTHOR]

An instantaneous frequency identification method of vibration signal based on linear chirplet transform and Wigner-Ville distribution is presented. This method has an obvious advantage in identifying closely spaced and time-varying frequencies. The matching pursuit algorithm is employed to select optimal chirplets, and a modified version of chirplet transform is presented to estimate nonlinear varying frequencies. Because of the high time resolution, the modified chirplet transform is superior to the original method. The proposed method is applied to time-varying systems with both linear and nonlinear varying stiffness and systems with closely spaced modes. A wavelet-based identification method is simulated to compare with the proposed method, with the comparison results showing that the chirplet-based method is effective and accurate in identifying both time-varying and closely spaced frequencies. A bat echolocation signal is used to verify the effectiveness of the modified chirplet transform. The result shows that it will significantly increase the accuracy of nonlinear frequency trajectory identification. [ABSTRACT FROM AUTHOR]

Background: The association of key genes in the transforming growth factor-β (TGF-β) signaling pathway and their gene polymorphisms with unexplained recurrent spontaneous abortion (URSA) is unclear., Objective: To investigate the association of gene polymorphisms related to the TGF-β signaling pathway in URSA women., Methods: The study population consisted of 80 women with URSA and 90 normal control women, of which 10 women with URSA and 10 normal control women underwent high-throughput sequencing to select loci, and the remaining 70 women with URSA and 80 normal control women underwent flight mass spectrometry experiments to verify gene loci polymorphism. A total of 7 polymorphic loci in interleukin-6 (IL-6), TGF-β1, TNF-α, SMAD1, and TNFRSF4 genes were screened by high-throughput sequencing combined with a review of databases. An SNP flight mass spectrometer (Mass ARRAY detection system) was applied to detect the polymorphisms and their frequencies in 70 women with URSA and 80 normal control women at the 7 gene loci., Results: Among the 7 loci of IL-6, TGF-β1, TNF-α, SMAD1, and TNFRSF4 genes, 2 loci were found to have significantly different allele and genotype frequency distributions between the 70 URSA and 80 normal controls, one was the IL-6 gene -174G/C locus (rs1800795), the risk of disease was 2.636 and 3.231 times higher in individuals carrying the C allele and CC genotype than in those carrying the G allele and GG genotype, respectively; the other was the TGF-β1 gene -509T/C locus (rs1800469), and the risk of disease was 1.959 and 3.609 times higher in individuals carrying the T allele and TT genotype than in those carrying the C allele and CC genotype, respectively. The remaining 5 genetic loci have no statistically significant., Conclusion: IL-6 gene -174G/C locus (rs1800795) genotype CC and allele C may be the causative factor of URSA, TGF-β1 gene -509T/C locus (rs1800469) genotype TT and allele T may be the causative factor of URSA, and polymorphisms of the 2 loci may be associated with URSA., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)