title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=701 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Growth of Lahontan cutthroat trout from multiple sources re-introduced into Sagehen Creek, CA link: https://peerj.com/articles/13322 last-modified: 2022-05-18 description: Lahontan cutthroat trout Oncorhynchus clarkii henshawi have experienced massive declines in their native range and are now a threatened species under the US Endangered Species Act. A key management goal for this species is re-establishing extirpated populations using translocations and conservation hatcheries. In California USA, two broodstocks (Pilot Peak and Independence Lake) are available for reintroduction, in addition to translocations from wild and naturalized sources. Pilot Peak and Independence Lake fish are hatchery stocks derived from native fish from the Truckee River basin and used for recovery activities in the western Geographic Management Unit Areas only, specifically within the Truckee River basin. Yet suitability of these sources for re-introduction in different ecosystem types remains an open and important topic. We conducted growth experiments using Lahontan cutthroat trout stocked into Sagehen Creek, CA, USA. Experiments evaluated both available broodstocks and a smaller sample of fish translocated representing a naturalized population of unknown origin from a nearby creek. Fish from the Independence Lake source had significantly higher growth in weight and length compared to the other sources. Further, Independence Lake fish were the only stock that gained weight on average over the duration of the experiment. Our experiments suggest fish from the Independence Lake brood stock should be considered in reintroduction efforts. creator: Jonathan E. Stead creator: Virginia L. Boucher creator: Peter B. Moyle creator: Andrew L. Rypel uri: https://doi.org/10.7717/peerj.13322 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Stead et al. title: Handcycling with concurrent lower body low-frequency electromyostimulation significantly increases acute oxygen uptake: implications for rehabilitation and prevention link: https://peerj.com/articles/13333 last-modified: 2022-05-18 description: BackgroundAcute increases in exercise-induced oxygen uptake (V̇O2) is crucial for aerobic training adaptations and depends on how much muscle mass is involved during exercising. Thus, handcycling is per se limited for higher maximal oxygen uptakes (V̇O2max) due to restricted muscle involvement. Handcycling with additional and simultaneous application of low-frequency electromyostimulation (EMS) to the lower extremities might be a promising stimulus to improve aerobic capacity in disabled and rehabilitative populations.MethodTwenty-six healthy young adults (13 female, age: 23.4 ± 4.5 years, height: 1.77 ± 0.09 m, mass: 71.7 ± 16.7 kg) completed 4 ×10 minutes of sitting (SIT), sitting with concurrent EMS (EMS_SIT), handcycling (60 rpm, 1/2 bodyweight as resistance in watts) (HANDCYCLE) and handcycling with concurrent EMS of the lower extremities (EMS_HANDCYCLE). During EMS_SIT and EMS_HANDCYCLE, low frequency EMS (impulse frequency: 4Hz, impulse width: 350 µs, continuous stimulation) was applied to gluteal, quadriceps and calf muscles. The stimulation intensity was selected so that the perceived pain could be sustained for a duration of 10 minutes (gluteus: 80.0 ± 22.7 mA, quadriceps: 94.5 ± 20.5 mA, calves: 77.5 ± 19.1 mA).ResultsSignificant mode-dependent changes of V̇O2 were found (p < 0.001, ηp2 = 0.852). Subsequent post-hoc testing indicated significant difference between SIT vs. EMS_SIT (4.70 ± 0.75 vs. 10.61 ± 4.28 ml min−1 kg−1, p < 0.001), EMS_SIT vs. HANDCYCLE (10.61 ± 4.28 vs. 13.52 ± 1.40 ml min−1 kg−1, p = 0.005), and between HANDCYCLE vs. EMS_HANDCYCLE (13.52 ± 1.40 vs. 18.98 ± 4.89 ml min−1 kg−1, p = 0.001).ConclusionHandcycling with simultaneous lower body low-frequency EMS application elicits notably higher oxygen uptake during rest and moderately loaded handcycling and may serve as an additional cardiocirculatory training stimuli for improvements in aerobic capacity in wheelchair and rehabilitation settings. creator: Ludwig Rappelt creator: Steffen Held creator: Lars Donath uri: https://doi.org/10.7717/peerj.13333 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Rappelt et al. title: Embryonic development of the moon jellyfish Aurelia aurita (Cnidaria, Scyphozoa): another variant on the theme of invagination link: https://peerj.com/articles/13361 last-modified: 2022-05-18 description: BackgroundAurelia aurita (Scyphozoa, Cnidaria) is an emblematic species of the jellyfish. Currently, it is an emerging model of Evo-Devo for studying evolution and molecular regulation of metazoans’ complex life cycle, early development, and cell differentiation. For Aurelia, the genome was sequenced, the molecular cascades involved in the life cycle transitions were characterized, and embryogenesis was studied on the level of gross morphology. As a reliable representative of the class Scyphozoa, Aurelia can be used for comparative analysis of embryonic development within Cnidaria and between Cnidaria and Bilateria. One of the intriguing questions that can be posed is whether the invagination occurring during gastrulation of different cnidarians relies on the same cellular mechanisms. To answer this question, a detailed study of the cellular mechanisms underlying the early development of Aurelia is required.MethodsWe studied the embryogenesis of A. aurita using the modern methods of light microscopy, immunocytochemistry, confocal laser microscopy, scanning and transmission electron microscopy.ResultsIn this article, we report a comprehensive study of the early development of A. aurita from the White Sea population. We described in detail the embryonic development of A. aurita from early cleavage up to the planula larva. We focused mainly on the cell morphogenetic movements underlying gastrulation. The dynamics of cell shape changes and cell behavior during invagination of the archenteron (future endoderm) were characterized. That allowed comparing the gastrulation by invagination in two cnidarian species—scyphozoan A. aurita and anthozoan Nematostella vectensis. We described the successive stages of blastopore closure and found that segregation of the germ layers in A. aurita is linked to the ’healing’ of the blastopore lip. We followed the developmental origin of the planula body parts and characterized the planula cells’ ultrastructure. We also found that the planula endoderm consists of three morphologically distinct compartments along the oral-aboral axis.ConclusionsEpithelial invagination is a fundamental morphogenetic movement that is believed as highly conserved across metazoans. Our data on the cell shaping and behaviours driving invagination in A. aurita contribute to understanding of morphologically similar morphogenesis in different animals. By comparative analysis, we clearly show that invagination may differ at the cellular level between cnidarian species belonging to different classes (Anthozoa and Scyphozoa). The number of cells involved in invagination, the dynamics of the shape of the archenteron cells, the stage of epithelial-mesenchymal transition that these cells can reach, and the fate of blastopore lip cells may vary greatly between species. These results help to gain insight into the evolution of morphogenesis within the Cnidaria and within Metazoa in general. creator: Yulia Kraus creator: Boris Osadchenko creator: Igor Kosevich uri: https://doi.org/10.7717/peerj.13361 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Kraus et al. title: Hospital-level characteristics of the standardised mortality ratio for ischemic heart disease: a retrospective observational study using Japanese administrative claim data from 2012 to 2019 link: https://peerj.com/articles/13424 last-modified: 2022-05-18 description: BackgroundIschemic heart disease (IHD) is one of the leading causes of mortality worldwide and imposes a heavy burden on patients. Previous studies have indicated that the optimal care for IHD during hospitalisation may reduce the risk of in-hospital mortality. The standardised mortality ratio (SMR) is an indicator for assessing the risk-adjusted in-hospital mortality ratio based on case-mix. This indicator can crucially identify hospitals that can be changed to improve patient safety and the quality of care. This study aimed to determine the hospital-level characteristics of the SMR for IHD in Japan.MethodsThis study was designed as a retrospective observational study using the Japanese administrative claim data from 2012 to 2019. The data of all hospital admissions with a primary diagnosis of IHD (ICD-10, I20-I25) were used. Patients with complete variables data were included in this study. Hospitals with less than 200 IHD inpatients in each 2-year period were excluded. The SMR was defined as the ratio of the observed number of in-hospital deaths to the expected number of in-hospital deaths multiplied by 100.The observed number of in-hospital deaths was the sum of the actual number of in-hospital deaths at that hospital, and the expected number of in-hospital deaths was the sum of the probabilities of in-hospital deaths. Ratios of in-hospital mortality was risk-adjusted using multivariable logistic regression analyses. The c-statistic and Hosmer-Lemeshow test were used to evaluate the predictive accuracy of the logistic models. Changes in SMRs in each consecutive period were assessed using Spearman’s correlation coefficient.ResultsA total of 64,831 were admitted patients with IHD in 27 hospitals as complete submission data. The SMRs showed wide variation among hospitals, ranging from 35.4 to 197.6, and analysis models indicated good predictive ability with a c-statistic of 0.93 (95% CI [0.92–0.94]) and Hosmer-Lemeshow test of 0.30. The results of chi-square tests and t-tests for all variables to assess the association with in-hospital mortality were P < 0.001. In the analysis of trends in each consecutive period, the SMRs showed positive correlations.ConclusionsThis study denoted that the SMRs for IHD could be calculated using Japanese administrative claim data. The SMR for IHD might contribute to the development of more appropriate benchmarking systems for hospitals to improve quality of care. creator: Ryo Onishi creator: Yosuke Hatakeyama creator: Kunichika Matsumoto creator: Kanako Seto creator: Koki Hirata creator: Yinghui Wu creator: Tomonori Hasegawa uri: https://doi.org/10.7717/peerj.13424 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Onishi et al. title: Melatonin increases growth properties in human dermal papilla spheroids by activating AKT/GSK3β/β-Catenin signaling pathway link: https://peerj.com/articles/13461 last-modified: 2022-05-18 description: BackgroundMelatonin, a neurohormone, maybe involved in physiological processes, such as antioxidation, anti-inflammation, and hair growth. In the present study, we investigated the effects of melatonin on proliferation and intracellular signaling in DP cells using a three-dimensional (3D) spheroid culture system that mimics the in vivo hair follicle system.MethodsDP cells were incubated in monolayer (2D) and 3D spheroid culture systems. The expression levels of melatonin receptors in DP cells were analyzed using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting. The effect of melatonin on the hair-inductive property of DP cells was analyzed using a WST-1-based proliferation assay, determination of DP spheroid size, expression analysis of DP signature genes, and determination of β-catenin stabilization in DP cells. The AKT/GSK3β/β-catenin signaling pathway associated with melatonin-induced β-catenin stabilization in DP cells was investigated by analyzing changes in upstream regulator proteins, including AKT, GSK3β, and their phosphorylated forms.ResultsThe expression levels of the melatonin receptors were higher in human DP cells than in human epidermal keratinocytes and human dermal fibroblast cells. Comparing the expression level according to the human DP cell culture condition, melatonin receptor expression was upregulated in the 3D culture system compared to the traditional two-dimensional monolayer culture system. Cell viability analysis showed that melatonin concentrations up to 1 mM did not affect cell viability. Moreover, melatonin increased the diameter of DP cell 3D spheroids in a dose-dependent manner. Immunoblotting and qRT-PCR analysis revealed that melatonin upregulated the expression of hair growth-related genes, including alkaline phosphatase, bone morphogenetic protein 2, versican, and wingless-int 5A, in a melatonin receptor-dependent manner. Cell fractionation analysis showed that melatonin increased the nuclear localization of β-catenin. This result correlated with the increased transcriptional activation of T-cell factor/lymphoid enhancer factor-responsive luciferase induced by melatonin treatment. Interestingly, melatonin induced the phosphorylation of protein kinase B/AKT at serine 473 residue and GSK-3β at serine 9 residue. To determine whether AKT phosphorylation at serine 473 induced β-catenin nuclear translocation through GSK3β phosphorylation at serine 9, the PI3K/AKT inhibitor LY294002 was cotreated with melatonin. Immunoblotting showed that LY294002 inhibited melatonin-induced phosphorylation of GSK3β at serine 9 residue and β-catenin activation.ConclusionCollectively, this report suggests that melatonin promotes growth properties by activating the AKT/GSK3β/β-catenin signaling pathway through melatonin receptors. creator: Sowon Bae creator: Yoo Gyeong Yoon creator: Ji Yea Kim creator: In-Chul Park creator: Sungkwan An creator: Jae Ho Lee creator: Seunghee Bae uri: https://doi.org/10.7717/peerj.13461 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Bae et al. title: Bayesian estimation for the mean of delta-gamma distributions with application to rainfall data in Thailand link: https://peerj.com/articles/13465 last-modified: 2022-05-18 description: Precipitation and flood forecasting are difficult due to rainfall variability. The mean of a delta-gamma distribution can be used to analyze rainfall data for predicting future rainfall, thereby reducing the risks of future disasters due to excessive or too little rainfall. In this study, we construct credible and highest posterior density (HPD) intervals for the mean and the difference between the means of delta-gamma distributions by using Bayesian methods based on Jeffrey’s rule and uniform priors along with a confidence interval based on fiducial quantities. The results of a simulation study indicate that the Bayesian HPD interval based on Jeffrey’s rule prior performed well in terms of coverage probability and provided the shortest expected length. Rainfall data from Chiang Mai province, Thailand, are also used to illustrate the efficacies of the proposed methods. creator: Theerapong Kaewprasert creator: Sa-Aat Niwitpong creator: Suparat Niwitpong uri: https://doi.org/10.7717/peerj.13465 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Kaewprasert et al. title: Inter-set rest configuration effect on acute physiological and performance-related responses to a resistance training session in terrestrial vs simulated hypoxia link: https://peerj.com/articles/13469 last-modified: 2022-05-18 description: BackgroundMetabolic stress is considered a key factor in the activation of hypertrophy mechanisms which seems to be potentiated under hypoxic conditions.This study aimed to analyze the combined effect of the type of acute hypoxia (terrestrial vs simulated) and of the inter-set rest configuration (60 vs 120 s) during a hypertrophic resistance training (RT) session on physiological, perceptual and muscle performance markers.MethodsSixteen active men were randomized into two groups based on the type of hypoxia (hypobaric hypoxia, HH: 2,320 m asl; vs normobaric hypoxia, NH: FiO2 of 15.9%). Each participant completed in a randomly counterbalanced order the same RT session in four separated occasions: two under normoxia and two under the corresponding hypoxia condition at each prescribed inter-set rest period. Volume-load (load × set × repetition) was calculated for each training session. Muscle oxygenation (SmO2) of the vastus lateralis was quantified during the back squat exercise. Heart rate (HR) was monitored during training and over the ensuing 30-min post-exercise period. Maximal blood lactate concentration (maxLac) and rating of perceived exertion (RPE) were determined after the exercise and at the end of the recovery period.ResultsVolume-load achieved was similar in all environmental conditions and inter-set rest period length did not appreciably affect it. Shorter inter-set rest periods displayed moderate increases in maxLac, HR and RPE responses in all conditions. Compared to HH, NH showed a moderate reduction in the inter-set rest-HR (ES > 0.80), maxLac (ES > 1.01) and SmO2 (ES > 0.79) at both rest intervals.ConclusionsResults suggest that the reduction in inter-set rest intervals from 120 s to 60 s provide a more potent perceptual, cardiovascular and metabolic stimulus in all environmental conditions, which could maximize hypertrophic adaptations in longer periods of training. The abrupt exposure to a reduced FiO2 at NH seems to reduce the inter-set recovery capacity during a traditional hypertrophy RT session, at least during a single acute exposition. These results cannot be extrapolated to longer training periods. creator: Cristina Benavente creator: Belén Feriche creator: Guillermo Olcina creator: Brad J. Schoenfeld creator: Alba Camacho-Cardenosa creator: Filipa Almeida creator: Ismael Martínez-Guardado creator: Rafael Timon creator: Paulino Padial uri: https://doi.org/10.7717/peerj.13469 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Benavente et al. title: Experimentally broadcast ocean surf and river noise alters birdsong link: https://peerj.com/articles/13297 last-modified: 2022-05-17 description: Anthropogenic noise and its effects on acoustic communication have received considerable attention in recent decades. Yet, the natural acoustic environment’s influence on communication and its role in shaping acoustic signals remains unclear. We used large-scale playbacks of ocean surf in coastal areas and whitewater river noise in riparian areas to investigate how natural sounds influences song structure in six songbird species. We recorded individuals defending territories in a variety of acoustic conditions across 19 study sites in California and 18 sites in Idaho. Acoustic characteristics across the sites included naturally quiet ‘control’ sites, ‘positive control’ sites that were adjacent to the ocean or a whitewater river and thus were naturally noisy, ‘phantom’ playback sites that were exposed to continuous broadcast of low-frequency ocean surf or whitewater noise, and ‘shifted’ playback sites with continuous broadcast of ocean surf or whitewater noise shifted up in frequency. We predicted that spectral and temporal song structure would generally correlate with background sound amplitude and that signal features would differ across site types based on the spectral profile of the acoustic environment. We found that the ways in which song structure varied with background acoustics were quite variable from species to species. For instance, in Idaho both the frequency bandwidth and duration of lazuli bunting (Passerina amoena) and song sparrow (Melospiza melodia) songs decreased with elevated background noise, but these song features were unrelated to background noise in the warbling vireo (Vireo gilvus), which tended to increase both the minimum and maximum frequency of songs with background noise amplitude. In California, the bandwidth of the trill of white-crowned sparrow (Zonotrichia leucophrys) song decreased with background noise amplitude, matching results of previous studies involving both natural and anthropogenic noise. In contrast, wrentit (Chamaea fasciata) song bandwidth was positively related to the amplitude of background noise. Although responses were quite heterogeneous, song features of all six species varied with amplitude and/or frequency of background noise. Collectively, these results provide strong evidence that natural soundscapes have long influenced vocal behavior. More broadly, the evolved behavioral responses to the long-standing challenges presented by natural sources of noise likely explain the many responses observed for species communicating in difficult signal conditions presented by human-made noise. creator: Veronica A. Reed creator: Cory A. Toth creator: Ryan N. Wardle creator: Dylan G.E. Gomes creator: Jesse R. Barber creator: Clinton D. Francis uri: https://doi.org/10.7717/peerj.13297 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Reed et al. title: Effects of three probiotics and their interactions on the growth performance of and nutrient absorption in broilers link: https://peerj.com/articles/13308 last-modified: 2022-05-17 description: The purpose of this study was to investigate the effects of three probiotics and their interactions on growth performance, intestinal digestion and absorption, and nutrient transporters in broilers. A total of 350 one-day-old male Arbor Acres broilers were randomly divided into seven groups: the control group (broilers receiving normal drinking water), groups P1, P2 and P3 (broilers receiving drinking water with 1% Lactobacillus casei, Lactobacillus acidophilus and Bifidobacterium lactis , respectively) and groups CP1, CP2 and CP3 (broilers receiving drinking water with a 1% compound probiotic mixture in 2:1:1, 1:2:1, 1:1:2 ratios, respectively). The feeding period was divided into two experimental periods: 1∼21 days and 22∼42 days. Compared to those in the control group, the broiler slaughter indexes and average daily feed intakes in the probiotics groups were not significantly different (P > 0.05), but the villus height in the small intestine increased significantly, and the crypt depth decreased significantly (P < 0.05). In the 1- to 21-day, experimental period, the broiler average daily gains in groups CP2 and CP3 were significantly greater than that in the control group. Amylase, lipase, and trypsin activities in the jejunum in groups CP and P3 increased significantly. GLUT2 mRNA expression in the probiotics group was significantly incresaed compared with that in the control group (P < 0.05). In the 22- to 42-day period, the average daily gain in the CP group was significantly greater than that in the control group. Amylase activity in the CP2 group, and lipase and trypsin activities in the CP, P1 and P3 groups increased significantly. The GLUT2 mRNA expression in the CP group increased significantly (P < 0.05). In summary, three probiotics and their interactions improved the digestibility and absorption of nutrients by increasing the activities of digestive enzymes, improving the morphology of the digestive tract, and upregulating the expression of GLUT2 mRNA in the intestinalcell membrane to improve the production performance in broilers. creator: Lihuan Zhang creator: Yanfei Wang creator: Ruonan Zhang creator: Hao Jia creator: Xuan Liu creator: Zhiwei Zhu uri: https://doi.org/10.7717/peerj.13308 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Zhang et al. title: Transcriptome changes in ERGIC3-knockdown hepatocellular carcinoma cells: ERGIC3 is a novel immune function related gene link: https://peerj.com/articles/13369 last-modified: 2022-05-17 description: ObjectiveThe expression of ERGIC3 is increased in a variety of tumors and promotes the growth and metastasis of liver cancer, but the molecular mechanism needs to be further studied.In this study, we aimed to analyze the molecular mechanism of ERGIC3 regulating the proliferation of human hepatocellular carcinoma (HCC) SMMC-7721 cells using transcriptomics.MethodsERGIC3 was knocked down in SMMC-7721 cells by RNAi technique, and the expression of ERGIC3 was detected by Q-RT-PCR and Western Blot. RNA sequencing was performed in the Illumina HiSeq platform in the control group and the ERGIC3i group and bioinformatics methods were selected to analyze the data.ResultsThe expression of ERGIC3 was reduced to 10% in SMMC-7721 cells by RNAi technique, and 176 genes were up-regulated and 34 genes were down-regulated in ERGIC3i group compared with the control group. Analysis of the pathways and biological processes that enrich the function of differentially expressed genes showed thatthese differentially expressed genes were mainly involved in vesicular transport, growth factors, PI3K-Akt, NOD-like, Jak-STAT, NF-kappa B and other protein kinase-coupled receptors mediated signal transduction pathways, tumor immune response, collagen-integrin receptor-actin axis, and miRNA pathways. More importantly, most of the significantly altered pathways were related to immunity. ERGIC3 may be a key immune-related gene.ConclusionBased on the transcriptomic analysis, the mechanism of ERGIC3 promoting the growth of HCC is link with the transport of growth factor receptor, cytokine receptor and collagen. Then it is involved in signal transduction pathways mediated by protein kinase-coupled receptors, PI3K-Akt, NOD-like, Jak-STAT and NF-kappa B. In particular, the mechanism is also involved in the ERGIC3-dependent immune pathways. ERGIC3 is a potential target for prevention and treatment of HCC. creator: Mengyuan Liu creator: Qiurong Zhao creator: Xiang Zheng creator: Lei Yang creator: Yanyu Zhao creator: Xueying Li creator: Mingsong Wu uri: https://doi.org/10.7717/peerj.13369 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Liu et al.