title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=389 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Trunk variability and local dynamic stability during gait after generalized fatigue induced by incremental exercise test in young women in different phases of the menstrual cycle link: https://peerj.com/articles/16223 last-modified: 2023-10-24 description: PurposeThe purpose of this study was to identify how generalized fatigue along with hormonal changes throughout the menstrual cycle affects trunk variability and local dynamic stability during gait.MethodsGeneral fatigue was induced by an incremental test on a treadmill, and the menstrual cycle was divided into three phases: follicular, ovulatory, and luteal. Twenty-six healthy, young volunteers (aged 18 to 28 years) who did not use oral contraceptives or other hormonal drugs with a regular menstrual cycle participated in the study. They walked on the treadmill for 4 min at the preferred speed, before the incremental test, followed by four sets of 4 min alternating between walking, also at preferred speed, and resting. From trunk kinematic data, the following were extracted: the mean of the standard deviation along strides, as a measure of variability, and the maximum Lyapunov exponent, as a measure of local dynamic stability (LDS).ResultsAfter the incremental test, variability increased, and LDS decreased. However, they showed a tendency to return to the initial value faster in women compared to previous results for men. In the follicular phase, which has less hormonal release, the volunteers had an almost complete recovery in LDS soon after the first rest interval, suggesting that female hormones can interfere with fatigue recovery. Nevertheless, concerning the LDS, it was significantly lower in the luteal phase than in the follicular phase.ConclusionWomen that are not taking oral contraceptives should be aware that they are susceptible to increased gait instabilities in the pre-menstrual phase after strenuous activities. creator: Ludmila Dos Anjos creator: Fábio Rodrigues creator: Sofia Scataglini creator: Rafael Reimann Baptista creator: Paula Lobo da Costa creator: Marcus Fraga Vieira uri: https://doi.org/10.7717/peerj.16223 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Dos Anjos et al. title: The comprehensive analysis of the prognostic and functional role of N-terminal methyltransferases 1 in pan-cancer link: https://peerj.com/articles/16263 last-modified: 2023-10-24 description: BackgroundNTMT1, a transfer methylase that adds methyl groups to the N-terminus of proteins, has been identified as a critical player in tumor development and progression. However, its precise function in pan-cancer is still unclear. To gain a more comprehensive understanding of its role in cancer, we performed a thorough bioinformatics analysis.MethodsTo conduct our analysis, we gathered data from multiple sources, including RNA sequencing and clinical data from the TCGA database, protein expression data from the UALCAN and HPA databases, and single-cell expression data from the CancerSEA database. Additionally, we utilized TISIDB to investigate the interaction between the tumor and the immune system. To assess the impact of NTMT1 on the proliferation of SNU1076 cells, we performed a CCK8 assay. We also employed cellular immunofluorescence to detect DNA damage and used flow cytometry to measure tumor cell apoptosis.ResultsOur analysis revealed that NTMT1 was significantly overexpressed in various types of tumors and that high levels of NTMT1 were associated with poor survival outcomes. Functional enrichment analysis indicated that NTMT1 may contribute to tumor development and progression by regulating pathways involved in cell proliferation and immune response. In addition, we found that knockdown of NTMT1 expression led to reduced cell proliferation, increased DNA damage, and enhanced apoptosis in HNSCC cells.ConclusionHigh expression of NTMT1 in tumors is associated with poor prognosis. The underlying regulatory mechanism of NTMT1 in cancer is complex, and it may be involved in both the promotion of tumor development and the inhibition of the tumor immune microenvironment. creator: Lifan Tan creator: Wensong Li creator: Qin Su uri: https://doi.org/10.7717/peerj.16263 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Tan et al. title: Integrative approaches to a revision of the liverwort in genus Aneura (Aneuraceae, Marchantiophyta) from Thailand link: https://peerj.com/articles/16284 last-modified: 2023-10-24 description: BackgroundThe genus Aneura Dumort. is a simple thalloid liverwort with cosmopolitan distributions. Species circumscription is problematic in this genus due to a limited number of morphological traits. Two species are currently reported from Thailand, including A. maxima and A. pinguis. At the global scale, A. pinguis is considered a cryptic species, as the species contains several distinct genetic groups without clear morphological differentiation. At the same time, the identity of A. maxima remains unclear. In this work, we examined the level of diversity of Aneura species found in Thailand using both morphological and molecular data.MethodsWe measured the morphological traits and generated the molecular data (four markers: trnL–F, trnH–psbA, rbcL, and ITS2) from the Thai specimens. The concatenated dataset was then used to reconstruct phylogeny. Species delimitation with GMYC, bPTP, ASAP, and ABGD methods was performed to estimate the number of putative species within the genus.ResultsThe samples of A. pinguis formed several clades, while A. maxima sequences from Poland were grouped in their clade and nested within another A. pinguis clade. We could not recover a sample of A. maxima from Thailand, even from the reported locality. Two putative species were detected among Thai Aneura samples. However, no morphological trait could distinguish the specimens from the two observed genetic groups.DiscussionThe previously observed paraphyletic nature of A. pinguis globally was also found among Thai samples, including several putative species. However, we could not confirm the identity of A. maxima from Thai specimens. The previous report could result from misidentification and problematic species circumscription within Aneura. The results highlighted the need to include multiple lines of evidence for the future taxonomic investigation of the group. creator: Nopparat Anantaprayoon creator: Passorn Wonnapinij creator: Ekaphan Kraichak uri: https://doi.org/10.7717/peerj.16284 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Anantaprayoon et al. title: Promoter from Chinese hamster elongation factor-1a gene and Epstein-Barr virus terminal repeats concatemer fragment maintain stable high-level expression of recombinant proteins link: https://peerj.com/articles/16287 last-modified: 2023-10-24 description: BackgroundThe Chinese hamster ovary (CHO) cell line is the main host for the high-titer production of therapeutic and diagnostic proteins in the biopharmaceutical industry. In most cases, plasmids for efficient protein expression in CHO cells are based on the cytomegalovirus (CMV) promoter. The autologous Chinese hamster eukaryotic translation elongation factor 1α (EEF1A1) promoter is a viable alternative to the CMV promoter in industrial applications. The EEF1A1 promoter and its surrounding DNA regions proved to be effective at maintaining high-level and stable expression of recombinant proteins in CHO cells. EEF1A1-based plasmids’ large size can lead to low transfection efficiency and hamper target gene amplification. We hypothesized that an efficient EEF1A1-based expression vector with a long terminal repeat fragment from the Epstein-Barr virus (EBVTR) could be truncated without affecting promoter strength or the long-term stability of target gene expression.MethodsWe made a series of deletions in the downstream flanking region of the EEF1A1 gene, and then in its upstream flanking region. The resulting plasmids, which coded for the enhanced green fluorescent protein (eGFP), were tested for the level of eGFP expression in the populations of stably transfected CHO DG44 cells and the stability of eGFP expression in the long-term culture in the absence of selection agents.ResultsIt was shown that in the presence of the EBVTR fragment, the entire downstream flanking region of the EEF1A1 gene could be excluded from the plasmid vector. Shortening of the upstream flanking region of the EEF1A1 gene to a length of 2.5 kbp also had no significant effect on the level of eGFP expression or long-term stability. The EBVTR fragment significantly increased expression stability for both the CMV and EEF1A1 promoter-based plasmids, and the expression level drop during the two-month culture was more significant for both CMV promoter-based plasmids.ConclusionTarget protein expression stability for the truncated plasmid, based on the EEF1A1 gene and EBVTR fragment, is sufficient for common biopharmaceutical applications, making these plasmid vectors a viable alternative to conventional CMV promoter-based vectors. creator: Maria V. Sinegubova creator: Nadezhda A. Orlova creator: Ivan I. Vorobiev uri: https://doi.org/10.7717/peerj.16287 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Sinegubova et al. title: Semaphorin4A promotes lung cancer by activation of NF-κB pathway mediated by PlexinB1 link: https://peerj.com/articles/16292 last-modified: 2023-10-24 description: BackgroundLung cancer (LC) is the most prevalent cancer with a poor prognosis. Semaphorin4A (Sema4A) is important in many physiological and pathological processes. This study aimed to explore the role and mechanism of Sema4A in LC.MethodsFirstly, Sema4A expression was analyzed by the available dataset and detected in human normal bronchial epithelial cell line (HBE) and LC cell line (NCI-H460). Then, LC cells were transfected with Sema4A siRNA, and the cells were stimulated by PlexinB1, PlexinB2, PlexinD1 blocking antibodies, IgG antibody, BAY 11-7082 (an inhibitor for NF-κB pathway) and Sema4A-Fc protein, alone or in combination. After transfection, PlexinB1 mRNA expression was analyzed. Next, the biological functions, including proliferative, migratory, invasive abilities and viability of the cells were detected by colony formation, scratch, Transwell and MTT assays, respectively. NF-κB, Stat3 and MAPK protein expressions were determined by western blot. Furthermore, the secretion of IL-6 in LC cells was tested by ELISA.ResultsSema4A was highly expressed in LC tissues and cells, could activate the NF-κB pathway and upregulate PlexinB1 mRNA expression. Furthermore, we observed that Sema4A knockdown suppressed the biological functions of NCI-H460 cells, while Sema4A-Fc protein reversed the situation. However, Sema4A-induced biological functions and activation in the NF-κB pathway were inhibited by PlexinB1 blocking antibody. Consistently, Sema4A promoted IL-6 production, which was down-regulated by PlexinB1 blocking antibody and BAY 11-7082.ConclusionsSema4A may facilitate LC development via the activation of the NF-κB pathway mediated by PlexinB1, suggesting that Sema4A would be a novel therapeutic target for LC treatment. creator: Xiang Wei creator: Zhili Liu creator: Yili Shen creator: Hui Dong creator: Kai Chen creator: Xuefei Shi creator: Yi Chen creator: Bin Wang creator: Shunli Dong uri: https://doi.org/10.7717/peerj.16292 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Wei et al. title: Multiple mediation effect of coping styles and self-esteem in the relationship between spousal support and pregnancy stress of married immigrant pregnant women link: https://peerj.com/articles/16295 last-modified: 2023-10-24 description: BackgroundThe purpose of this study was to identify the total, direct, and indirect influence of spousal support on pregnancy stress among married immigrant pregnant women. The study aimed to determine the relative magnitudes of specific mediating effects of coping styles and self-esteem.MethodA cross-sectional correlational survey was conducted in Jeonnam with 206 married immigrant pregnant women. Data were collected from September 7 to November 7 in 2019. A self-report questionnaire was used to measure spousal support, pregnancy stress, coping styles, and self-esteem. The study employed a linear multiple regression analysis to examine the potential multi-mediating effects. The effect size was set at 0.15, the significance level at 0.05, and the power at 0.95. Through the analysis, the researchers explored the mediating mechanisms among the variables and identified the presence of multi-mediating effects.ResultsThe effect sizes (b) and statistical significance (p) for the predictors were as follows: problem-focused coping (b = 0.13, p = 0.001), emotion-focused coping (b = 0.11, p = 0.004), and self-esteem (b = 0.10, p < 0.001). Emotion-focused coping (b = 0.26, p = 0.001) and self-esteem (b = −0.20, p = 0.035) had a significant impact on pregnancy stress. The total effect of spousal support on pregnancy stress was significant at −0.25 (p < 0.001), and the direct effect was also significant at −0.26 (p < 0.001). We observed significant mediating effects for emotion-focused coping and self-esteem.ConclusionsAs a result of this study, the self-esteem of married immigrant pregnant women can have a protective effect by preventing the aggravation of pregnancy stress in the relationship between spousal support and pregnancy stress. Meanwhile, the emotion-focused coping style can balance out the effect of self-esteem. Therefore, in order to alleviate the stress of pregnancy for women, it is necessary to provide intervention to help improve self-esteem with spousal support. In addition, nursing professionals should help them use appropriate coping styles. creator: So-hyun Moon creator: Miok Kim uri: https://doi.org/10.7717/peerj.16295 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Moon and Kim title: Population genetic structure and hybrid zone analyses for species delimitation in the Japanese toad (Bufo japonicus) link: https://peerj.com/articles/16302 last-modified: 2023-10-24 description: Hybridization following secondary contact may produce different outcomes depending on the extent to which genetic diversity and reproductive barriers have accumulated during isolation. The Japanese toad, Bufo japonicus, is distributed on the main islands of Japan. In the present study, we applied multiplexed inter-simple sequence repeat genotyping by sequencing to achieve the fine-scale resolution of the genetic cluster in B. j. japonicus and B. j. formosus. We also elucidated hybridization patterns and gene flow degrees across contact zones between the clusters identified. Using SNP data, we found four genetic clusters in B. j. japonicus and B. j. formosus and three contact zones of the cluster pairs among these four clusters. The two oldest diverged lineages, B. j. japonicus and B. j. formosus, formed a narrow contact zone consistent with species distinctiveness. Therefore, we recommend that these two subspecies be elevated to the species level. In contrast, the less diverged pairs of two clusters in B. j. japonicus and B. j. formosus, respectively, admixed over a hundred kilometers, suggesting that they have not yet developed strong reproductive isolation and need to be treated as conspecifics. These results will contribute to resolving taxonomic confusion in Japanese toads. creator: Kazumi Fukutani creator: Masafumi Matsui creator: Kanto Nishikawa uri: https://doi.org/10.7717/peerj.16302 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Fukutani et al. title: Evaluation of SARS-CoV-2 identification methods through surveillance of companion animals in SARS-CoV-2-positive homes in North Carolina, March to December 2020 link: https://peerj.com/articles/16310 last-modified: 2023-10-24 description: We collected oral and/or rectal swabs and serum from dogs and cats living in homes with SARS-CoV-2-PCR-positive persons for SARS-CoV-2 PCR and serology testing. Pre-COVID-19 serum samples from dogs and cats were used as negative controls, and samples were tested in duplicate at different timepoints. Raw ELISA results scrutinized relative to known negative samples suggested that cut-offs for IgG seropositivity may require adjustment relative to previously proposed values, while proposed cut-offs for IgM require more extensive validation. A small number of pet dogs (2/43, 4.7%) and one cat (1/21, 4.8%) were positive for SARS-CoV-2 RNA, and 28.6 and 37.5% of cats and dogs were positive for anti-SARS-CoV-2 IgG, respectively. creator: Taylor E. Gin creator: Elizabeth A. Petzold creator: Diya M. Uthappa creator: Coralei E. Neighbors creator: Anna R. Borough creator: Craig Gin creator: Erin Lashnits creator: Gregory D. Sempowski creator: Thomas Denny creator: Dorothee Bienzle creator: J. Scott Weese creator: Benjamin J. Callahan creator: Christopher W. Woods uri: https://doi.org/10.7717/peerj.16310 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Gin et al. title: ET-1 receptor type B (ETBR) overexpression associated with ICAM-1 downregulation leads to inflammatory attenuation in experimental autoimmune myocarditis link: https://peerj.com/articles/16320 last-modified: 2023-10-24 description: BackgroundAn experimental autoimmune myocarditis rat model was established by subcutaneous injection of porcine myocardial myosin (PCM). The effect of ET-1 receptor type B (ETBR) overexpression on autoimmune myocarditis was observed via tail vein injection of ETBR overexpression lentivirus in rats. We further investigated the mechanisms involved in the regulation of autoimmune myocarditis by ETBR overexpression.MethodsSix rats were randomly selected from 24 male Lewis rats as the NC group, and the remaining 18 rats were injected with PCM on Day 0 and Day 7, to establish the experimental autoimmune myocarditis (EAM) rat model. The 18 rats initially immunized were randomly divided into three groups: the EAM group, ETBR-oe group, and GFP group. On Day 21 after the initial immunization of rats, cardiac echocardiography and serum brain natriuretic peptide (BNP) analysis were performed to evaluate cardiac function, myocardial tissue HE staining was performed to assess myocardial tissue inflammatory infiltration and the myocarditis score, and mRNA expression of IFN-γ, IL-12, and IL-17 was detected by qRT-PCR. Subsequently, immunohistochemical analysis was performed to detect the localization and expression of the ETBR and ICAM-1 proteins, and the expression of ETBR and ICAM-1 was verified by qRT-PCR and western blotting methods.ResultsOn Day 21 after initial immunization, left ventricular end-diastolic diameter (LVEDd), left ventricular end-systolic diameter (LVEDs), and serum BNP concentrations increased in the hearts of rats in the EAM group compared with the NC group (P < 0.01), and ejection fraction (EF) and fractional shortening (FS) decreased compared with those of the normal control (NC) group (P < 0.01). LVEDd, LVEDs, and serum BNP concentrations decreased in the ETBR-oe group compared with the EAM group, while EF and FS increased significantly (P < 0.01). HE staining showed that a large number of inflammatory cell infiltrates, mainly lymphocytes, were observed in the EAM group, and the myocarditis score was significantly higher than that of the NC group (P < 0.01). Compared with that of the EAM group, myocardial tissue inflammatory cell infiltration was significantly reduced in the ETBR-oe group, and the myocarditis scores were significantly lower (P < 0.01). The mRNAs of the inflammatory factors IFN-γ, IL-12 and IL-17 in myocardial tissue of rats in the EAM group exhibited elevated levels compared with those of the NC group (P < 0.01) while the mRNAs of IFN-γ, IL-12 and IL-17 were significantly decreased in the ETBR-oe group compared with the EAM group (P < 0.01). Immunohistochemistry showed that the staining depth of ETBR protein in myocardial tissue was greater in the EAM group than in the NC group, and significantly greater in the ETBR-oe group than in the EAM group, while the staining depth of ICAM-1 was significantly greater in the EAM group than in the NC group, and significantly lower in the ETBR-oe group than in the EAM group. The ICAM-1 expression level was significantly higher in the EAM group than in the NC group (P < 0.01), and was significantly lower in the ETBR-oe groupthan in the EAM group (P < 0.01). creator: Peng Yang creator: Fangfei Li creator: Jiangfeng Tang creator: Qingshan Tian creator: Zhenzhong Zheng uri: https://doi.org/10.7717/peerj.16320 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Yang et al. title: Molecular characterization, expression patterns and cellular localization of BCAS2 gene in male Hezuo pig link: https://peerj.com/articles/16341 last-modified: 2023-10-24 description: BackgroundBreast carcinoma amplified sequence 2 (BCAS2) participates in pre-mRNA splicing and DNA damage response, which is implicated in spermatogenesis and meiosis initiation in mouse. Nevertheless, the physiological roles of BCAS2 in the testes of large mammals especially boars remain largely unknown.MethodsIn this study, testes were collected from Hezuo pig at three development stages including 30 days old (30 d), 120 days old (120 d), and 240 days old (240 d). BCAS2 CDS region was firstly cloned using RT-PCR method, and its molecular characteristics were identified using relevant bioinformatics software. Additionally, the expression patterns and cellular localization of BCAS2 were analyzed by quantitative real-time PCR (qRT-PCR), Western blot, immunohistochemistry and immunofluorescence.ResultsThe cloning and sequence analysis indicated that the Hezuo pig BCAS2 CDS fragment encompassed 678 bp open reading frame (ORF) capable of encoding 225 amino acid residues, and possessed high identities with some other mammals. The results of qRT-PCR and Western blot displayed that BCAS2 levels both mRNA and protein were age-dependent increased (p < 0.01). Additionally, immunohistochemistry and immunofluorescence results revealed that BCAS2 protein was mainly observed in nucleus of gonocytes at 30 d testes as well as nucleus of spermatogonia and Sertoli cells at 120 and 240 d testes. Accordingly, we conclude that BCAS2 is critical for testicular development and spermatogenesis of Hezuo pig, perhaps by regulating proliferation or differentiation of gonocytes, pre-mRNA splicing of spermatogonia and functional maintenance of Sertoli cells, but specific mechanism still requires be further investigated. creator: Yuran Tang creator: Bo Zhang creator: Haixia Shi creator: Zunqiang Yan creator: Pengfei Wang creator: Qiaoli Yang creator: Xiaoyu Huang creator: Shuangbao Gun uri: https://doi.org/10.7717/peerj.16341 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Tang et al.