title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=741 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Immunogenicity mechanism of mRNA vaccines and their limitations in promoting adaptive protection against SARS-CoV-2 link: https://peerj.com/articles/13083 last-modified: 2022-03-09 description: Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) in late 2019, hundreds of millions of people have been infected worldwide. There have been unprecedented efforts in acquiring effective vaccines to confer protection against the disease. mRNA vaccines have emerged as promising alternatives to conventional vaccines due to their high potency with the capacity for rapid development and low manufacturing costs. In this review, we summarize the currently available vaccines against SARS-CoV-2 in development, with the focus on the concepts of mRNA vaccines, their antigen selection, delivery and optimization to increase the immunostimulatory capability of mRNA as well as its stability and translatability. We also discuss the host immune responses to the SARS-CoV-2 infection and expound in detail, the adaptive immune response upon immunization with mRNA vaccines, in which high levels of spike-specific IgG and neutralizing antibodies were detected after two-dose vaccination. mRNA vaccines have been shown to induce a robust CD8+T cell response, with a balanced CD4+ TH1/TH2 response. We further discuss the challenges and limitations of COVID-19 mRNA vaccines, where newly emerging variants of SARS-CoV-2 may render currently deployed vaccines less effective. Imbalanced and inappropriate inflammatory responses, resulting from hyper-activation of pro-inflammatory cytokines, which may lead to vaccine-associated enhanced respiratory disease (VAERD) and rare cases of myocarditis and pericarditis also are discussed. creator: Mohd Zulkifli Salleh creator: Mohd Nor Norazmi creator: Zakuan Zainy Deris uri: https://doi.org/10.7717/peerj.13083 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Salleh et al. title: Distinct metabolic profiling is correlated with bisexual flowers formation resulting from exogenous ethephon induction in melon (Cucumis melo L.) link: https://peerj.com/articles/13088 last-modified: 2022-03-09 description: Melon (Cucumis melo L.) is an agronomically important vegetable. Most cultivars of melon are andromonoecious and bisexual flowers only emerged from the leaf axil of lateral branches. However, the regulatory mechanism contributing to the occurrence of bisexual flowers were still obscure. In this study, ethephon was applied in two common cultivars of melon. In control without ethephon treatment, no bisexual flower was made in the main stem. However, 6.56 ± 1.42 and 6.63 ± 0.55 bisexual flowers were respectively induced in main stem of ‘Yangjiaocui-QX’ and ‘Lvbao’ after ethephon treatment, and induced bisexual flowers distributed in 12–20 nodes of main stem. During the formation of bisexual flowers, 41 metabolites were significantly up-regulated and 98 metabolites were significantly down-regulated. According to the KEGG enrichment analysis of 139 different metabolites, a total of 30 pathways were mapped and KEGG terms of “Phenylalanine, tyrosine and tryptophan biosynthesis”, “Phenylalanine metabolism” and “Flavone and flavonol biosynthesis” were significantly enriched. In three significantly enriched KEGG terms, shikimic acid, L-tryptophan, L-phenylalanine, and kaempferol were significantly up-regulated while L-tyrosine, 4-hydroxycinnami acid and luteolin were significantly down-regulated in ET compared to CK. Different metabolites were also classified depend on major class features and 14 classes were acquired. The results of metabonomics and endogenous hormone identification indicated that ethylene could enhance the concentration of salicylic acid, methyl jasmonate, ABA and IAA. This study provided an important theoretical foundation for inducing bisexual flowers in main stem and breeding new varieties of melon in future. creator: Siyu Fang creator: Yaqian Duan creator: Lanchun Nie creator: Wensheng Zhao creator: Jiahao Wang creator: Jiateng Zhao creator: Liping Zhao creator: Lei Wang uri: https://doi.org/10.7717/peerj.13088 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Fang et al. title: A bZIP transcription factor, PqbZIP1, is involved in the plant defense response of American ginseng link: https://peerj.com/articles/12939 last-modified: 2022-03-08 description: American ginseng (Panax quinquefolius L.) is a perennial medicinal plant that has a long usage history in China. However, root rot, which is mainly caused by Fusarium solani can severely reduce the yield and quality of American ginseng, but no disease-resistant variety of American ginseng exists, and the resistance against this disease is not yet well understood. Thus, it is very urgent to analyze the interaction mechanism regulating the interactions between American ginseng and F. solani to mine disease resistance genes. Using transcriptome data and quantitative polymerase chain reaction (qPCR), we screened the transcription factor PqbZIP1 in response to induction by chitin. Yeast self-activation and subcellular localization experiments proved that PqbZIP1 showed transcriptional activity and was localized in the plant nucleus. In addition, qPCR showed that the highest relative expression level was in the roots, wherein chitin and F. solani inhibited and activated the expression of PqbZIP1, respectively, in American ginseng. Additionally, PqbZIP1 significantly inhibited the growth of the Pseudomonas syringae pv. tomato D36E strain in Nicotiana benthamiana, where expressing PqbZIP1 in N. benthamiana increased the jasmonic acid, salicylic acid, and abscisic acid content. Furthermore, PqbZIP1 expression was continually increased upon inoculation with F. solani. Hence, this study revealed that the PqbZIP1 transcription factor might mediate multiple hormonal signaling pathway to modulate root rot disease resistance in American ginseng, and provided important information to breed disease-resistant American ginseng. creator: Shanshan Yang creator: Xiaoxiao Zhang creator: Ximei Zhang creator: Yanmeng Bi creator: Weiwei Gao uri: https://doi.org/10.7717/peerj.12939 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Yang et al. title: Associations between the rs5498 (A > G) and rs281432 (C > G) polymorphisms of the ICAM1 gene and atherosclerotic cardiovascular disease risk, including hypercholesterolemia link: https://peerj.com/articles/12972 last-modified: 2022-03-08 description: BackgroundAtherosclerotic cardiovascular disease (ASCVD) originates from complex risk factors, including age, gender, dyslipidemia, obesity, race, genetic and genetic variation. ICAM1 gene polymorphisms are a significant risk factor for ASCVD. However, the impact of the rs5498 and rs281432 polymorphisms on the prevalence of hypercholesterolemia (HCL) has not been reported. Therefore, we determine the relationships between single nucleotide polymorphisms (SNPs), including rs5498 and rs281432 on Intercellular adhesion molecule 1 gene (ICAM1) and ASCVD susceptibility in patients with HCL.MethodsThe clinical characteristics of 278 participants were assessed, and classified to groups having HCL and without HCL. ICAM1 SNPs genotyping was performed by DNA sequencing, and ICAM1 expression was measured using real-time PCR.ResultsPositive dominant model rs5498 participants had twice the risk of HCL (95% confidence interval (CI): [1.24–3.23], P = 0.005). The frequency of the G allele in rs5498 was 1.69 times higher in participants with HCL than in controls (95% CI [1.15–2.47], P = 0.007). Participants with the rs5498 AG or GG variants and high ICAM1 mRNA expression (≥3.12) had 2.49 times the risk (95% CI [1.42–4.38], P = 0.001), and those with a high LDL-C concentration (≥3.36 mmol/L) had 2.09 times the risk (95% CI [1.19–3.66], P = 0.010) of developing ASCVD compared with those with low ICAM1 mRNA and LDL-C levels. Interestingly, participants carrying the rs5498 AG or GG variants who had tachycardia (resting heart rates (RHRs) >100 beats/min) had a 5.02-times higher risk than those with a lower RHR (95% CI [1.35–18.63], P = 0.016).ConclusionsIt may consider the G allele in ICAM1rs5498 is associated with a higher risk of ASCVD in Thai people with HCL, and is also positively associated with ICAM1 mRNA expression, LDL-C concentration, and RHR. creator: Naruemon Wechjakwen creator: Amornrat Aroonnual creator: Pattaneeya Prangthip creator: Ngamphol Soonthornworasiri creator: Pornpimol Panprathip Phienluphon creator: Jirayu Lainampetch creator: Karunee Kwanbunjan uri: https://doi.org/10.7717/peerj.12972 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Wechjakwen et al. title: Microbial community spatial structures in Luzhou-flavored liquor pit muds with different brewing materials link: https://peerj.com/articles/12987 last-modified: 2022-03-08 description: BackgroundAlthough studies have shown that Bacteroidetes, Clostridiales, and Lactobacillales are the main components of the microbial community in pit mud during the brewing of Luzhou-flavored liquor, little is known about the effect of brewing materials on spatial structures of this microbiome.MethodsHigh-throughput sequencing of the V4–V5 region of prokaryotic 16S rRNA gene was performed to analyze the microbial community diversity and spatial heterogeneity in Luzhou-flavored liquor pit muds with different brewing ingredients. The structural characteristics and heterogeneous spatial distribution of the pit mud microbial communities were examined using bioinformatics and multivariate statistical analysis methods.ResultsOur results showed that Euryarchaeota, Actinobacteria, Bacteroidetes, Chlorobi, Chloroflexi, Firmicutes, Proteobacteria, Synergistetes, Tenericutes, and WWE1 were the dominant phyla in the pit mud microbiome. The Shannon and Simpson indices of the pit mud microbiome with three grains (M3G) in the upper layer were significantly lower than those in middle layer and bottom, whereas those of the pit mud microbiome with five grains (M5G) in bottom were significantly lower than those in middle layer (p < 0.05). There were significant differences in the microbial community compositions between the pit muds with different brewing ingredients and locations in the same pit (p < 0.05). T78 of Anaerolinaceae, Butyrivibrio, Dehalobacter_Syntrophobotulus, Desulfosporosinus, Asteroleplasma, and vadinCA02 of Synergistaceae were significantly enriched in M3G, whereas Prevotella, Vagococcus, Caldicoprobacter, Butyrivibrio, Coprococcus, Dorea, Sporanaerobacter, Tepidimicrobium, TissierellaSoehngenia, RFN20 of Erysipelotrichaceae, Sutterella, 125ds10 of Alteromonadales, Vibrio, and Sphaerochaeta were significantly enriched in M5G. This study provides a theoretical basis for exploring the influence of brewing ingredients in pit muds on the production of Luzhou-flavored liquor and the specific influence of pit mud microorganisms in different locations on liquor production. creator: Jinjin Li creator: Hongzhao Sun creator: Qian Wang creator: Yunfei Cai creator: Zhu Shi creator: Jianlei Jia creator: Lei Zheng creator: Ru Jiang creator: Lingmei Gao uri: https://doi.org/10.7717/peerj.12987 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Li et al. title: Abubidentin A, New Oleanane-type Triterpene Ester from Abutilon bidentatum and its antioxidant, cholinesterase and antimicrobial activities link: https://peerj.com/articles/13040 last-modified: 2022-03-08 description: BackgroundThis work describes the phytochemical and biological investigation of aerial parts of Abutilon bidentatum Hochst. Of Saudi origin.MethodologyPetroleum ether fraction of ethanolic extract A. bidentatum was fractionated on a silica gel column and further purified with different chromatographic procedures for the isolation of chemical compounds. The chemical structures of all the pure isolated compounds were elucidated by the interpretation of their spectral data using IR, UV, 1H, 13C NMR, and MS spectroscopy and chemical methods (alkaline hydrolysis) as well as comparison with data reported in the literature. The extract and isolated compounds were evaluated for antioxidant, cholinesterase inhibitory, and antimicrobial activities.ResultsA new oleanane-type triterpene ester, namely abubidentin A (3) (α, 3β, 30-trihydroxy-29-carboxy-olean-9(11), 12-diene-3-dotriacontanoate), along with two known compounds: 2-hydroxydocosanoic acid (1) and stigmasta-22-ene-3-β-ol (2) were isolated from the aerial parts of Abutilon bidentatum Hochst. (Malvaceae). Concerning the biological potential, the abubidentinA displayed antioxidant, cholinesterase inhibitory and antimicrobial activities. AbubidentinA possessed strong antioxidant activity against DPPH and ABTS+ radical scavenging assays. This new triterpene exhibited high inhibition against acetylcholinesterase (IC50 38.13 ± 0.07 µgmL−1) and butyrylcholinesterase (IC50 32.68 ± 0.37 µgmL−1). Abubidentin A displayed promising antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus (125–150 µgmL−1).ConclusionThese findings suggest A. bidentatum can contribute as a source of new biologically active compounds, especially antioxidants and antimicrobial agents. creator: Gadah A. Al-Hamoud creator: Nawal M. Al-Musayeib creator: Musarat Amina creator: Sabrin R.M. Ibrahim uri: https://doi.org/10.7717/peerj.13040 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Al-Hamoud et al. title: Comparison of the composition and function of gut microbes between adult and juvenile Cipangopaludina chinensis in the rice snail system link: https://peerj.com/articles/13042 last-modified: 2022-03-08 description: Cipangopaludina chinensis is an important economic value snail species with high medicinal value. The gut microbes of aquatic animals plays a vital role in food digestion and nutrient absorption. Herein, we aimed at high-throughput sequencing of 16S rRNA to further investigate whether there were differences in the composition and function of gut microbes of adult and juvenile C. chinensis snails, as well as sediments. This study found that the microbial diversity of the sediment was significantly higher than that of the snails gut (P < 0.001), but there was no significant difference between the gut flora of adult and juvenile snails (P > 0.05). A total of 47 phyla and 644 genera were identified from all samples. Proteobacteria and Verrucomicrobia were the two dominant phyla in all samples, and overall relative abundances was 48.2% and 14.2%, respectively. Moreover, the relative abundances of Aeromonas and Luteolibacter in the gut of juvenile snails (30.8%, 11.8%) were higher than those of adults (27.7%, 10.6%) at the genus level (P > 0.05). Then, four indicator genera were found, namely Flavobacterium, Silanimonas, Geobacter and Zavarzinella, and they abundance in the gut of juvenile snails was significantly higher than that of adults (P < 0.05). This results imply the potential development of Silanimonas as a bait for juvenile snail openings. We observed that Aeromonas was the primary biomarker of the snail gut and sediments (P < 0.001), and it may be a cellulose-degrading bacteria. Function prediction revealed significantly better biochemical function in the snail gut than sediments (P < 0.001), but no significant differences in adult and juvenile snail (P > 0.05). In conclusion, studies show that the snail gut and sediment microbial composition differ, but the two were very similar. The microbial composition of the snail gut was relatively stable and has similar biological functions. These findings provide valuable information for in-depth understanding of the relationship between snails and environmental microorganisms. creator: Kangqi Zhou creator: Junqi Qin creator: Haifeng Pang creator: Zhong Chen creator: Yin Huang creator: Wenhong Li creator: Xuesong Du creator: Luting Wen creator: Xianhui Pan creator: Yong Lin uri: https://doi.org/10.7717/peerj.13042 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Zhou et al. title: Four new species of Ctenodrilus, Raphidrilus, and Raricirrus (Cirratuliformia, Annelida) in Japanese waters, with notes on their phylogenetic position link: https://peerj.com/articles/13044 last-modified: 2022-03-08 description: Four new species of annelids, Ctenodrilus japonicus sp. nov., Raphidrilus misakiensis sp. nov., Raphidrilus okinawaensis sp. nov., and Raricirrus anubis sp. nov., are described based on specimens collected from Japanese waters. Ctenodrilus japonicus sp. nov. inhabits the interstitial environment and can be distinguished from the other congeners by the following features: (i) total of 16 chaetigers, (ii) chaetigers 1–3 with stout hooks, (iii) minute body (approximately 1 mm in length), (iv) all parapodia with the same number of chaetae (two notochaetae; two neurochaetae), and (v) presence of dorsal and ventral papillae. Raphidrilus misakiensis sp. nov. lives under intertidal stones and can be distinguished from other congeners by having pectinate neurochaetae. Raphidrilus okinawaensis sp. nov. inhabits the interstitial environment and can be distinguished from other congeners by: (i) absence of annulation on the peristomium and achaetous segment and (ii) presence of a heart body in chaetigers 4–5. Raricirrus anubis sp. nov. inhabits whale bones and can be distinguished from other congeners by the following features: (i) presence of a heart body in chaetigers 9–14, (ii) presence of capillary neurochaetae on chaetiger 1, and (iii) presence of simple curved spines. A phylogenetic tree based on partial sequences of cytochrome c oxidase subunit I and 16S rRNA from the new species and other cirratulid worms showed that Raphidrilus is included in Cirratuliformia. This is the first record of Raphidrilus and Raricirrus from Japanese waters. creator: Naoto Jimi creator: Shinta Fujimoto creator: Yoshihiro Fujiwara creator: Kohei Oguchi creator: Toru Miura uri: https://doi.org/10.7717/peerj.13044 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Jimi et al. title: Essential…but also vulnerable? Work intensification, effort/reward imbalance, fatigue and psychological health of Spanish cargo drivers during the COVID-19 pandemic link: https://peerj.com/articles/13050 last-modified: 2022-03-08 description: ObjectiveThis study investigates the combined effect of the Effort/Reward Imbalance (ERI) model of stress and work intensification within the context of the COVID-19 pandemic on the psychological health (general and work-related fatigue, and psychological strain) of cargo drivers, one of the most demanded workforces during the first year of this pandemic.MethodsFor this cross-sectional research, the data provided by n = 1,013 professional drivers from the different 17 autonomous communities (regions) of Spain were analyzed. Participants answered a questionnaire composed of the short version of the Effort Reward Imbalance (ERI) questionnaire, a Work Intensification Scale (WIS) designed for this study, the fatigue subscale of the Checklist Individual Strength (CIS), the Need for Recovery after Work Scale (NFR), and the General Health Questionnaire (GHQ).ResultsHierarchical regression analyses show that both (ERI and work intensification) models significantly predict driver’s fatigue and psychological strain. The effect of work intensification exists above and beyond the effect of effort/reward imbalance, which has been previously related to the safety performance of cargo drivers.ConclusionsThese findings suggest that the ERI and work intensification models can be complementarily used, especially in scenarios introducing substantial changes in the work environment, such as the COVID-19 crisis. Also, the results of this study support the need to intervene in the working conditions of professional drivers in order to improve their psychological health and well-being during both pandemic and post-pandemic times, as crisis-related management interventions are necessary to promote health and safety in professional drivers in potentially similar contexts in the future. creator: Luis Montoro creator: Boris Cendales creator: Francisco Alonso creator: Adela Gonzalez-Marin creator: Ignacio Lijarcio creator: Javier Llamazares creator: Sergio A. Useche uri: https://doi.org/10.7717/peerj.13050 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Montoro et al. title: Effect of individualized weight management intervention on excessive gestational weight gain and perinatal outcomes: a randomized controlled trial link: https://peerj.com/articles/13067 last-modified: 2022-03-08 description: It is unclear whether weight management is still effective for pregnant women with excessive weight gain in the second or third trimester in China. This study adopted individualized weight management intervention for pregnant women with abnormal weight gain in the second or third trimester, to analyze the effect of intervention by observing the gestational weight gain and perinatal outcomes. This randomized controlled trial was performed at Aerospace Center Hospital. The obstetrician determined whether the pregnant women gained too much weight in the second or third trimester according to the Institute of Medicine guidelines, and randomly divided the pregnant women who gained too much weight in the second or third trimester into the intervention group or the control group according to the inclusion and exclusion criteria. The pregnant women in the intervention group and in the control group all received routine prenatal examination and diet nutrition education by the doctors in the Department of Obstetrics and Gynecology. The intervention group underwent individualized weight management, including individualized diet, exercise, psychological assessment, cognitive intervention and continuous communication, the whole process is tracked and managed by professional nutritionists. The obstetrician collected the prenatal examination data and pregnancy outcome data of all enrolled pregnant women. The primary outcome measure was weight gain during pregnancy. A generalized linear model and a logistic regression model were used to compare the outcomes between the two groups. In total, 348 pregnant women participated in this study with 203 in the intervention group and 145 in the control group. The whole gestational weight gain in the intervention group (15.8 ± 5.4 Kg) was lower than that in the control group (17.5 ± 3.6 Kg; adjusted β =  − 1.644; 95% CI [−2.660–−0.627]; P = 0.002). The percent of pregnant women with excessive weight gainbefore delivery was 54.2% (110/203) in the intervention group, which was lower than 69.7% (101/145) in the control group (adjusted RR = 0.468; 95% CI [0.284–0.769] P = 0.003). The pregnant women given the individualized weight management intervention from the second to the third trimester experienced less weight gain than that from the third trimester (15.5 ± 5.6 Kg vs. 16.2 ± 5.2 Kg), but without significant difference (P = 0.338). Lower rates of GDM, preeclampsia and gestational hypertension, higher rates of fetal distress and puerperal infection were observed in the intervention group than in the control group (all P < 0.05). Individualized weight management during the second or third trimesters is still beneficial for pregnant women who gain excessive weight and can decrease the associated adverse outcomes. creator: Mei-Yan Xu creator: Yan-Jun Guo creator: Li-Juan Zhang creator: Qing-Bin Lu uri: https://doi.org/10.7717/peerj.13067 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Xu et al.