title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=511 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Current environmental status of the oyster farms on Lake Kamo in Japan; viral control of the harmful bloom of Heterocapsa circularisquama link: https://peerj.com/articles/14813 last-modified: 2023-05-11 description: Lake Kamo is an enclosed, low-inflow estuary connected to the open sea that is famous for oyster farming in Japan. In the fall of 2009, this lake experienced its first bloom of the dinoflagellate Heterocapsa circularisquama, which selectively kills bivalve mollusks. This species has been detected exclusively in southwestern Japan. The completely unexpected outbreak of H. circularisquama in the northern region is believed to have been caused by the contamination of purchased seedlings with this species. The water quality and nutrient data collected by our group from July through October over the past 10 years revealed that the environment of Lake Kamo has not changed significantly. However, in the open water around Sado Island, where Lake Kamo is located, the water temperature has increased by 1.80 °C in the last 100 years, which is equivalent to 2–3-fold the world average. This has resulted in a rise in the sea level, which is expected to further deteriorate the water exchange between Lake Kamo and the open sea and low dissolved oxygen in the bottom layer of the Lake and the associated dissolution of nutrients from the bottom sediment. Therefore, seawater exchange has become insufficient and the lake has become nutrient rich, making it prone to the establishment of microorganisms, such as H. circularisquama, once they have been introduced. We developed a method to mitigate the damage caused by the bloom by spraying sediments containing the H. circularisquama RNA virus (HcRNAV), which infects H. circularisquama. After ∼10 years of performing various verification tests, including field trials, this method was used at the Lake in 2019. During the 2019 H. circularisquama growth season, a small amount of sediment containing HcRNAV was sprayed on the lake three times, which resulted in a decrease in H. circularisquama and an increase in HcRNAV, indicating that this method is effective in diminishing the bloom. creator: Natsuko Nakayama creator: Saho Kitatsuji creator: Masami Hamaguchi uri: https://doi.org/10.7717/peerj.14813 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Nakayama et al. title: Analysis of IGHA1 and other salivary proteins post half marathon in female participants link: https://peerj.com/articles/15075 last-modified: 2023-05-11 description: BackgroundHigh-intensity exercise (HIE), such as that in marathons and triathlons, suppresses transient local and systemic immunity. Serum and salivary immunoglobulin heavy constant alpha 1 (IGHA1) are major markers of immunosuppression by HIE. Although much is known about the systemic immunosuppressive response, little is known about its local response in the oral cavity, lungs, bronchial tubes, and skin. The oral cavity allows bacteria or viruses to enter the body. Saliva covers the epidermis of the oral cavity and plays an important role in the local stress response by preventing infection. In this study, we examined the properties of saliva secreted during the local stress response for half-marathon (HM) induced IGHA1 protein expression using quantitative proteomics.MethodsThe Exercise Group (ExG) (19 healthy female university students) participated in a HM race. The Non-Exercise Group (NExG) (16 healthy female university students) did not participate in the ExG. The ExG saliva samples were collected 1 h pre and 2 h and 4 h post-HM. The NExG saliva samples were collected at the same time intervals. The saliva volume, protein concentration, and relative IGHA1 expression were analyzed. In addition, 1 h pre and 2 h post- HM saliva samples were analyzed by iTRAQ. The identified factors in iTRAQ were analyzed for the ExG and the NExG using western blotting.ResultsWe identified kallikrein 1 (KLK1), immunoglobulin kappa chain (IgK), and cystatin S (CST4) as suppression factors, as well as IGHA1, which has been reported to be an immunological stress marker. IGHA1 (p = 0.003), KLK1 (p = 0.011), IGK (p = 0.002), and CST4 (p = 0.003) were suppressed 2 h post-HM compared with their levels pre HM, and IGHA1 (p < 0.001), KLK1 (p = 0.004), and CST4 (p = 0.006) were suppressed 4 h post-HM. There was also a positive correlation between IGHA1, IGK, and CST4 levels at 2 and 4 h post-HM. In addition, KLK1 and IGK levels at 2 h post-HM were positively correlated.ConclusionOur study demonstrated that the salivary proteome is regulated, and antimicrobial proteins are suppressed post-HM. These results suggest that oral immunity was transiently suppressed post-HM. The positive correlation of each protein at 2 and 4 h post-HM suggests that the suppressed state was similarly regulated up to 4 h after a HM. The proteins identified in this study may have applications as stress markers for recreational runners and individuals who perform moderate to HIE on a regular basis. creator: Yosuke Maruyama creator: Tomoaki Seki creator: Seiichi Ando creator: Hiroki Tanabe creator: Hitoshi Mori uri: https://doi.org/10.7717/peerj.15075 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Maruyama et al. title: Young Zambian infants with symptomatic RSV and pertussis infections are frequently prescribed inappropriate antibiotics: a retrospective analysis link: https://peerj.com/articles/15175 last-modified: 2023-05-11 description: Pediatric community-acquired pneumonia (CAP) remains a pressing global health concern, particularly in low-resource settings where diagnosis and treatment rely on empiric, symptoms-based guidelines such as the WHO’s Integrated Management of Childhood Illness (IMCI). This study details the delivery of IMCI-based health care to 1,320 young infants and their mothers in a low-resource urban community in Lusaka, Zambia during 2015. Our Southern Africa Mother Infant Pertussis Study (SAMIPS) prospectively monitored a cohort of mother/infant pairs across infants’ first four months of life, recording symptoms of respiratory infection and antibiotics prescriptions (predominantly penicillins), and tested nasopharyngeal (NP) samples for respiratory syncytial virus (RSV) and Bordetella pertussis. Our retrospective analysis of the SAMIPS cohort found that symptoms and antibiotics use were more common in infants (43% and 15.7%) than in mothers (16.6% and 8%), while RSV and B. pertussis were observed at similar rates in infants (2.7% and 32.5%) and mothers (2% and 35.5%), albeit frequently at very low levels. In infants, we observed strong associations between symptoms, pathogen detection, and antibiotics use. Critically, we demonstrate that non-macrolide antibiotics were commonly prescribed for pertussis infections, some of which persisted across many weeks. We speculate that improved diagnostic specificity and/or clinician education paired with timely, appropriate treatment of pertussis could substantially reduce the burden of this disease while reducing the off-target use of penicillins. creator: Christian E. Gunning creator: Pejman Rohani creator: Lawrence Mwananyanda creator: Geoffrey Kwenda creator: Zacharia Mupila creator: Christopher J. Gill uri: https://doi.org/10.7717/peerj.15175 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Gunning et al. title: Tandem mass tag-based quantitative proteomic analysis identification of succinylation related proteins in pathogenesis of thoracic aortic aneurysm and aortic dissection link: https://peerj.com/articles/15258 last-modified: 2023-05-11 description: BackgroundThoracic aortic aneurysm and dissection (TAAD) are devastating cardiovascular diseases with a high rate of disability and mortality. Lysine succinylation, a newly found post-translational modification, has been reported to play an important role in cardiovascular diseases. However, how succinylation modification influences TAAD remains obscure.MethodsAscending aortic tissues were obtained from patients with thoracic aortic aneurysm (TAA, n = 6), thoracic aortic dissection (TAD) with pre-existing aortic aneurysm (n = 6), and healthy subjects (n = 6). Global lysine succinylation level was analyzed by Western blotting. The differentially expressed proteins (DEPs) were analyzed by tandem mass tag (TMT) labeling and mass spectrometry. Succinylation-related proteins selected from the literature review and AmiGO database were set as a reference inventory for further analysis. Then, the pathological aortic sections were chosen to verify the proteomic results by Western blotting and qRT-PCR.ResultsThe level of global lysine succinylation significantly increased in TAA and TAD patients compared with healthy subjects. Of all proteins identified by proteomic analysis, 197 common DEPs were screened both in TAA and TAD group compared with the control group, of which 93 proteins were significantly upregulated while 104 were downregulated. Among these 197 DEPs, OXCT1 overlapped with the succinylation-related proteins and was selected as the target protein involved in thoracic aortic pathogenesis. OXCT1 was further verified by Western blotting and qRT-PCR, and the results showed that OXCT1 in TAA and TAD patients was significantly lower than that in healthy donors (p < 0.001), which was consistent with the proteomic results.ConclusionsOXCT1 represents novel biomarkers for lysine succinylation of TAAD and might be a therapeutic target in the future. creator: Yu Zhang creator: Hongwei Zhang creator: Haiyue Wang creator: Chenhao Wang creator: Peng Yang creator: Chen Lu creator: Yu Liu creator: Zhenyuan Xu creator: Yi Xie creator: Jia Hu uri: https://doi.org/10.7717/peerj.15258 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Zhang et al. title: m6A eraser ALKBH5 mitigates the apoptosis of cardiomyocytes in ischemia reperfusion injury through m6A/SIRT1 axis link: https://peerj.com/articles/15269 last-modified: 2023-05-11 description: Recent studies have shown that the potential regulatory role of N6-methyladenine (m6A) modification may affect the occurrence and development of various cardiovascular diseases. However, the regulatory mechanism of m6A modification on myocardial ischemia reperfusion injury (MIRI) is rarely reported. A mouse model of myocardial ischemia reperfusion (I/R) was established by ligation and perfusion of the left anterior descending coronary artery, and a cellular model of hypoxia/reperfusion (H/R) was conducted in cardiomyocytes (CMs). We found that the protein expression of ALKBH5 in myocardial tissues and cells were decreased, accompanied by increased m6A modification level. Overexpression of ALKBH5 significantly inhibited H/R-induced oxidative stress and apoptosis in CMs. Mechanistically, there was an enriched m6A motif in the 3′-UTR of SIRT1 genome, and ALKBH5 overexpression promoted the stability of SIRT1 mRNA. Furthermore, results using overexpression or knockdown of SIRT1 confirmed the protective effect of SIRT1 on H/R induced CMs apoptosis. Together, our study reveals a critical role of ALKBH5-medicated m6A on CM apoptosis, supplying an important regulating effect of m6A methylation in ischemic heart disease. creator: Liangliang Liu creator: Zhen Liu uri: https://doi.org/10.7717/peerj.15269 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Liu and Liu title: Incidence, genetic diversity, and antimicrobial resistance profiles of Vibrio parahaemolyticus in seafood in Bangkok and eastern Thailand link: https://peerj.com/articles/15283 last-modified: 2023-05-11 description: BackgroundEmergence of Vibrio parahaemolyticus pandemic strain O3:K6 was first documented in 1996. Since then it has been accounted for large outbreaks of diarrhea globally. In Thailand, prior studies on pandemic and non-pandemic V. parahaemolyticus had mostly been done in the south. The incidence and molecular characterization of pandemic and non-pandemic strains in other parts of Thailand have not been fully characterized. This study examined the incidence of V. parahaemolyticus in seafood samples purchased in Bangkok and collected in eastern Thailand and characterized V. parahaemolyticus isolates. Potential virulence genes, VPaI-7, T3SS2, and biofilm were examined. Antimicrobial resistance (AMR) profiles and AMR genes (ARGs) were determined.MethodsV. parahaemolyticus was isolated from 190 marketed and farmed seafood samples by a culture method and confirmed by polymerase chain reaction (PCR). The incidence of pandemic and non-pandemic V. parahaemolyticus and VPaI-7, T3SS2, and biofilm genes was examined by PCR. AMR profiles were verified by a broth microdilution technique. The presence of ARGs was verified by genome analysis. V. parahaemolyticus characterization was done by multilocus sequence typing (MLST). A phylogenomic tree was built from nucleotide sequences by UBCG2.0 and RAxML softwares.ResultsAll 50 V. parahaemolyticus isolates including 21 pathogenic and 29 non-pathogenic strains from 190 samples had the toxRS/old sequence, indicating non-pandemic strains. All isolates had biofilm genes (VP0950, VP0952, and VP0962). None carried T3SS2 genes (VP1346 and VP1367), while VPaI-7 gene (VP1321) was seen in two isolates. Antimicrobial susceptibility profiles obtained from 36 V. parahaemolyticus isolates revealed high frequency of resistance to colistin (100%, 36/36) and ampicillin (83%, 30/36), but susceptibility to amoxicillin/clavulanic acid and piperacillin/tazobactam (100%, 36/36). Multidrug resistance (MDR) was seen in 11 isolates (31%, 11/36). Genome analysis revealed ARGs including blaCARB (100%, 36/36), tet(34) (83%, 30/36), tet(35) (42%, 15/36), qnrC (6%, 2/36), dfrA6 (3%, 1/36), and blaCTX-M-55 (3%, 1/36). Phylogenomic and MLST analyses classified 36 V. parahaemolyticus isolates into 5 clades, with 12 known and 13 novel sequence types (STs), suggesting high genetic variation among the isolates.ConclusionsAlthough none V. parahaemolyticus strains isolated from seafood samples purchased in Bangkok and collected in eastern Thailand were pandemic strains, around one third of isolates were MDR V. parahaemolyticus strains. The presence of resistance genes of the first-line antibiotics for V. parahaemolyticus infection raises a major concern for clinical treatment outcome since these resistance genes could be highly expressed under suitable circumstances. creator: Chartchai Changsen creator: Somsak Likhitrattanapisal creator: Kamonwan Lunha creator: Wiyada Chumpol creator: Surasak Jiemsup creator: Anuphap Prachumwat creator: Darin Kongkasuriyachai creator: Supawadee Ingsriswang creator: Soraya Chaturongakul creator: Aekarin Lamalee creator: Suganya Yongkiettrakul creator: Sureemas Buates uri: https://doi.org/10.7717/peerj.15283 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Changsen et al. title: Kekveus brevisulcatus sp. nov., a new featherwing beetle from mid-Cretaceous amber of northern Myanmar (Coleoptera: Ptiliidae) link: https://peerj.com/articles/15306 last-modified: 2023-05-11 description: Ptiliidae (featherwing beetles) is a group of minute staphylinoid beetles with a scarce fossil record. Here a second member of the Mesozoic genus Kekveus Yamamoto et al. is reported from mid-Cretaceous Burmese amber, with detailed morphology obtained through confocal microscopy. Kekveus brevisulcatus Li, Yamamoto, Newton & Cai sp. nov. shares with K. jason Yamamoto et al. the unpaired medial pronotal fovea and narrowly separated transverse metacoxae, but can be separated from the latter based on its less elongate body, shorter pronotal foveae, and much weaker transverse depression on the head. Our phylogenetic analyses support the discheramocephalin affinity of Kekveus, although its relationship with other members of Discheramocephalini cannot be confidently resolved. creator: Yan-Da Li creator: Shûhei Yamamoto creator: Alfred F. Newton creator: Chen-Yang Cai uri: https://doi.org/10.7717/peerj.15306 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Li et al. title: Bone marrow mesenchymal stem cell-derived exosomes protect podocytes from HBx-induced ferroptosis link: https://peerj.com/articles/15314 last-modified: 2023-05-11 description: IntroductionHepatitis B virus-associated glomerulonephritis (HBV-GN) is a common secondary kidney disease in China, the pathogenesis of which is not completely clear, and there is still a lack of effective treatment.MethodsThe mechanism of exosomes derived from bone marrow mesenchymal stem cells (BMSCs) was investigated by using HBx-transfected human renal podocytes. Cell viability was detected by CCK8 assay. Iron and malondialdehyde (MDA) contents were detected by using commercial kits. Reactive oxygen species (ROS) levels were measured by flow cytometry analysis. The expression of ferroptosis related molecules was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. The effect of miR-223-3p transferred by BMSC-derived exosomes on HBx-overexpressing podocytes was proved by using miR-223-3p inhibitor.ResultsThe cell viability of podocytes reduced at 72 h or 96 h after the transfection of lentivirus overexpressing HBx protein (p < 0.05). Ferroptosis-related proteins, including glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) were down-regulated upon HBx overexpression, while acyl-CoA synthetase long-chain family member 4 (ACSL4) was up-regulated (p < 0.05). Intracellular levels of iron, MDA, and ROS were also enhanced (p < 0.05). BMSC-derived exosomes protected against ferroptosis induced by HBx overexpression in podocytes. miR-223-3p was enriched in BMSC-derived exosomes. Application of miR-223-3p inhibitor reversed the protective effect of BMSC-derived exosomes on HBx-induced ferroptosis in podocytes.ConclusionBMSC-derived exosomes inhibit HBx-induced podocyte ferroptosis by transferring miR-223-3p. creator: Xiaoqian Yang creator: Yani Yu creator: Baoshuang Li creator: Yueqi Chen creator: Moxuan Feng creator: Yongzheng Hu creator: Wei Jiang uri: https://doi.org/10.7717/peerj.15314 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Yang et al. title: Multi-omics analysis of pyroptosis regulation patterns and characterization of tumor microenvironment in patients with hepatocellular carcinoma link: https://peerj.com/articles/15340 last-modified: 2023-05-11 description: BackgroundHepatocellular carcinoma (HCC) is a primary malignant tumor of the liver, and pyroptosis has been identified as a novel cellular program that plays a role in numerous diseases including cancer. However, the functional role of pyroptosis in HCC remains unclear. The purpose of this study is to explore the relationship between the two found hub genes and provide targets for clinical treatment.MethodsThe Cancer Genome Atlas (TCGA) database was used to collect the gene data and clinically-related information of patients with HCC. After the differentially expressed genes (DEGs) were identified, they were intersected with the genes related to pyroptosis, and a risk prediction model was established to predict the overall survival (OS). Subsequently, drug sensitivity analysis, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Set Enrichment Analysis (GSEA), and Gene Set Variation Analysis (GSVA) was used to analyze the biological characteristics of the DEGs. Different immune cell infiltration and related pathways were analyzed, and hub genes were identified by protein-protein interaction (PPI). Finally, the expression of hub genes was verified by real-time quantitative PCR (qRT-PCR) and immunohistochemistry.ResultsWe conducted a comprehensive bioinformatics analysis to investigate the molecular mechanisms of pyroptosis in hepatocellular carcinoma (HCC). A total of 8,958 differentially expressed genes were identified, and 37 differentially expressed genes were associated with pyroptosis through intersection. Moreover, we developed an OS model with excellent predictive ability and discovered the differences in biological function, drug sensitivity, and immune microenvironment between high-risk and low-risk groups. Through enrichment analysis, we found that the differentially expressed genes are related to various biological processes. Then, 10 hub genes were identified from protein-protein interaction networks. Finally, midkine (MDK) was screened from the 10 hub genes and further verified by PCR and immunohistochemistry, which revealed its high expression in HCC.ConclusionWe have developed a reliable and consistent predictive model based on the identification of potential hub genes, which can be used to accurately forecast the prognosis of patients, thus providing direction for further clinical research and treatment. creator: Bingbing Shang creator: Ruohan Wang creator: Haiyan Qiao creator: Xixi Zhao creator: Liang Wang creator: Shaoguang Sui uri: https://doi.org/10.7717/peerj.15340 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2023 Shang et al. title: Temperament and character in an Australian sample: examining cross-sectional associations of personality with age, sex, and satisfaction with life link: https://peerj.com/articles/15342 last-modified: 2023-05-11 description: ObjectivePersonality can influence how we interpret and react to our day-to-day life circumstances. Temperament and character are the primary dimensions of personality, and both are influenced genetically. Temperament represents our emotional core, while character reflects our goals and values as we develop through life. Research shows that where people live, their social, economic, and physical environment can influence attitudes and behaviors, and these have links to variations in personality traits. There are few studies that focus on Australian personality as temperament and character. Using an Australian general population sample, we examined the psychometric properties of the Temperament and Character Inventory (TCIR140) and investigated the associations between TCIR140 traits with both sociodemographic variables and measures of well-being. In addition, we investigated differences in temperament and character between our Australian general population sample and published results of similar studies from other countries.MethodsAustralians (N = 1,510) completed the Temperament and Character Inventory (TCIR-140), the Positive and Negative Affect Scale and the Satisfaction with Life Scale. Cronbach’s alpha and confirmatory factor analysis (CFA) examined the TCIR-140 psychometrics. Correlation analyzes, independent sample t-tests and ANOVA with post-hoc comparisons analyzed the sample.ResultsCronbach’s alphas were high, ranging from α = 0.78–0.92, and the CFA confirmed two constructs of temperament and character. Females were higher in Harm Avoidance (p < 0.001), Reward Dependence (p < 0.001), and Cooperativeness (p < 0.001) compared to males, who were higher in Self-Directedness (p < 0.001). Age groups showed significant differences among all temperament and character traits (p < 0.001) except for Reward Dependence (p = 0.690). Young adults had the least resilient personality profile and poorest measures of well-being. Correlations with measures of temperament and character, well-being and affect were all in the expected direction.ConclusionsTemperament and character are related to indicators of wellbeing and differs by age and sex. This Australian sample demonstrate a temperament that is high in Persistence and a character high in Self-Directedness and Cooperativeness with an overall postive affect and a general satisfaction with life. In comparison to other countries, Australians in this sample differ in levels of several traits, demonstrating a cautious and independent temperament with a character that is cooperative, industrious, and self-reliant. Young-adults in comparison to older groups have a temperament and character profile that is prone to negative emotions and a lower satisfaction with life. creator: Diann S. Eley creator: Vikas Bansal creator: C. Robert Cloninger creator: Janni Leung uri: https://doi.org/10.7717/peerj.15342 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2023 Eley et al.