title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=1105 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Reliability and validity of an equanimity questionnaire: the two-factor equanimity scale (EQUA-S) link: https://peerj.com/articles/9405 last-modified: 2020-07-07 description: BackgroundMany studies have revealed the positive impact of mindfulness training on mental health and proposed equanimity as a general outcome in contemplative research. Despite recent interest, relatively few studies have empirically examined equanimity and measurement instruments are still lacking. The main goal of this study was to develop an Equanimity Scale (the EQUA-S) in a Western population with or without meditation experience, based on previous definitions of equanimity, in order to investigate its relations with the relevant psychological constructs and health outcomes.MethodsAdults from the general population (N = 265; Mage = 34.81) completed various measures: the EQUA-S, mindfulness, hyper-sensitivity, avoidance and fusion, impulsivity, personality, alexithymia, sensitivity to punishment and reward and frequency of problematic addictive behaviors. The dimensionality of the EQUA-S was examined using Factor Analyses. The convergent validity of this new scale was investigated using Pearson’s Correlations.ResultsThe results of a factor analysis revealed two dimensions of equanimity: an even-minded state of mind (E-MSM) and a hedonic independence (HI) component. While the E-MSM was positively related to emotional stability, adaptive emotional regulation and several mindfulness-related abilities, HI was found to correlate negatively with addictive issues.DiscussionThe relations with personality constructs and possible related cognitive processes are discussed. creator: Catherine Juneau creator: Nicolas Pellerin creator: Elliott Trives creator: Matthieu Ricard creator: Rébecca Shankland creator: Michael Dambrun uri: https://doi.org/10.7717/peerj.9405 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Juneau et al. title: Molecular, physiological, and biochemical characterization of extracellular lipase production by Aspergillus niger using submerged fermentation link: https://peerj.com/articles/9425 last-modified: 2020-07-07 description: BackgroundExtracellular production of fungal lipases especially the lipases obtained from the Aspergilli has gained immense interest in recent years due to its diverse biotechnological applications. In this study, we focused on determining the fermentation parameters required for the optimal lipase production.MethodsA total of 256 fungal isolates were obtained from oil seeds. From each genus, one isolate was selected to evaluate lipase production using phenol red and tributyrin plate assays. Lipase activity was estimated using the spectrophotometric pNPP hydrolysis assay. The highest lipase producer isolates were identified using 18S ribosomal RNA gene sequencing. The genetic variability was determined by random amplified polymorphic DNA (RAPD) analysis and the dendrogram was constructed using the unweighted pair group method with arithmetic averages method. The isolates were examined in a submerged fermentation culture (Smf) to measure the effect of temperature, pH, incubation time, carbon source, nitrogen source, inoculum volume, and lipid source on lipase production.ResultsEleven isolates belonging to the genus Aspergillus were analyzed for lipase production where they were found to be the highest lipase producers among various fungal genera. All the tested isolates were identified as A. niger using 18s rRNA sequencing. Genetic diversity was evaluated among all of the studied A. niger isolates using RAPD primers. The RAPD primers were used to amplify 285 loci, of which five were polymorphic (1.75%) and seven were monomorphic (2.45%). Thus, a high level of genetic diversity was observed among all isolates. The tributyrin test and the lipase activity assay identified five strains of A. niger as high lipase producers, and their optimal enzyme activities were 709.74, 532.54, 735.64, 794.62, and 787.69 U/ml. The optimal conditions for lipase production were as follows: 40 °C, pH 7.5, 1% fructose as the carbon source, 1% yeast extract as the nitrogen source, 2% palm oil, 2.5 × 107 spores/ml suspension, and 3 days of incubation.ConclusionsThe current study provides a comprehensive characterization of the optimal conditions, which are essential to enhance lipase production in five A. niger isolates. creator: Amira Hassan Alabdalall creator: Norah Ayad ALanazi creator: Sumayh A. Aldakeel creator: Sayed AbdulAzeez creator: J. Francis Borgio uri: https://doi.org/10.7717/peerj.9425 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Alabdalall et al. title: Modifying effects of leaf litter extracts from invasive versus native tree species on copper-induced responses in Lemna minor link: https://peerj.com/articles/9444 last-modified: 2020-07-07 description: Invasive plant species tend to migrate from their native habitats under favourable climatic conditions; therefore, trophic and other relationships in ecosystems are changing. To investigate the effect of natural organic matter derived from native Alnus glutinosa tree species and from invasive in Lithuania Acer negundo tree species on copper toxicity in Lemna minor, we analysed the dynamics of Cu binding in aqueous leaf litter extracts (LLE) and plant accumulation, morphophysiological parameters, and antioxidative response. The results revealed that A. glutinosa LLE contained polyphenols (49 mg pyrogallol acid equivalent (PAE)/g DM) and tannins (7.5 mg PAE/g DM), while A. negundo LLE contained only polyphenols (23 mg PAE/g DM). The ability of LLE to bind Cu increased rapidly over 1.5–3 h to 61% and 49% of the total Cu concentration (6.0 ± 0.9 mg/L), respectively for A. glutinosa (AG) and A. negundo (AN), then remained relatively stable until 48 h. At the same time, L. minor accumulated 384, 241 or 188 µg Cu/g FW when plants were exposed to Cu (100 µM CuSO4), Cu with 100 mg/L dissolved organic carbon (DOC) from either AG LLE or AN LLE, accordingly. Catalase (CAT) and guaiacol peroxidase (POD) played a dominant role in hydrogen peroxide scavenging when plants were exposed to Cu and 10 or 100 mg/L DOCAG mixtures in both the first (up to 6h) and the second (6–48 h) response phases. Due to functioning of oxidative stress enzymes, the levels of the lipid peroxidation product malondialdehyde (MDA) reduced in concentration-dependent manner, compared to Cu treatment. When combining Cu and DOCAN treatments, the most sensitive enzymes were POD, ascorbate peroxidase and glutathione reductase. Their activities collectively with CAT were sufficient to reduce MDA levels to Cu-induced in the initial, but not the second response phase. These data suggest that leaf litter extracts of different phenolic compositions elicited different antioxidant response profiles resulting in different reductions of Cu stress, thus effecting L. minor frond and root development observed after seven days. The complex data from this study may be useful in modelling the response of the aquatic ecosystem to a changing environment. creator: Rolandas Karitonas creator: Sigita Jurkonienė creator: Kazys Sadauskas creator: Jūratė Vaičiūnienė creator: Levonas Manusadžianas uri: https://doi.org/10.7717/peerj.9444 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Karitonas et al. title: Transcriptome analysis reveals a reprogramming energy metabolism-related signature to improve prognosis in colon cancer link: https://peerj.com/articles/9458 last-modified: 2020-07-07 description: Although much progress has been made to improve treatment, colon cancer remains a leading cause of cancer death worldwide. Metabolic reprogramming is a significant ability of cancer cells to ensure the necessary energy supply in uncontrolled proliferation. Since reprogramming energy metabolism has emerged as a new hallmark of cancer cells, accumulating evidences have suggested that metabolism-related genes may serve as key regulators of tumorigenesis and potential biomarkers. In this study, we analyzed a set of reprogramming energy metabolism-related genes by transcriptome analysis in colon cancer and revealed a five-gene signature that could significantly predict the overall survival. The reprogramming energy metabolism-related signature could distinguish patients into high-risk and low-risk groups with significantly different survival times (P = 0.0011; HR = 1.92; 95% CI [1.29–2.87]). Its prognostic value was confirmed in another two independent colon cancer cohorts (P = 5.2e–04; HR = 2.09, 95%; CI [1.37–3.2] for GSE17538 and P = 3.8e−04; HR = 2.08, 95% CI [1.37–3.16] for GSE41258). By multivariable analysis, we found that the signature was independent of clinicopathological features. Its power in promoting risk stratification of the current clinical stage was then evaluated by stratified analysis. Moreover, the signature could improve the power of the TNM stage for the prediction of overall survival and could be used in patients who received adjuvant chemotherapy. Overall, our results demonstrated the important role of the reprogramming energy metabolism-related signature in promoting stratification of high-risk patients, which could be diagnostic of adjuvant therapy benefit. creator: Xinxin Zhang creator: Jinyuan Xu creator: Yujia Lan creator: Fenghua Guo creator: Yun Xiao creator: Yixue Li creator: Xia Li uri: https://doi.org/10.7717/peerj.9458 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Zhang et al. title: Consolidation chemotherapy may improve pathological complete response for locally advanced rectal cancer after neoadjuvant chemoradiotherapy: a retrospective study link: https://peerj.com/articles/9513 last-modified: 2020-07-07 description: BackgroundPatients with locally advanced rectal cancer (LARC) have an improved prognosis if achieved a pathological complete response (pCR) on account of neoadjuvant chemoradiation therapy (nCRT). However, the proportion of patients achieving pCR is only 8–24%. The purpose of this study was to explore whether the addition of consolidation chemotherapy to nCRT could improve pCR rate in patients with LARC.Materials and MethodsThe subjects were 144 individuals with clinical stage II (T3–4, N0) or III (any T, N1–2) LARC who had received neoadjuvant CRT followed by total mesorectal excision (TME). Eighty-three patients in the consolidation chemotherapy group received two cycles XELOX between CRT and TME, while 61 patients in the standard treatment group without consolidation chemotherapy. The pCR (ypT0N0), tumor downstaging (ypT0-2N0) after TME and adverse events (AEs) during and post treatment were compared between the treatment groups using multivariable logistic regression analysis. To adjust the unbalanced variables for the primary endpoint, logistic regression analysis and stratified analysis were performed.ResultsThe consolidation chemotherapy group improved pCR rate (19.3% vs 4.9%, p = 0.01) and tumor downstaging rate (45.8% vs 24.6%, p = 0.009) compared to the standard treatment group. After adjustment for clinical tumor stage, clinical nodal stage and time interval to surgery, patients with consolidation chemotherapy were more likely to reach pCR (adjusted odds ratio 4.91, 95% CI [1.01–23.79], p = 0.048). AEs during and post treatment in the two groups were 54.1% vs 49.3% (p = 0.57), respectively. In addition, the incidence of any grade 1–2 AEs in the two groups was 93.4% vs 95.1% (p = 0.93), while the incidence of grade 3 AEs was 1.6% versus 2.4% (p = 0.74), respectively. No grade 4 AEs occurred in two groups.ConclusionsThe addition of neoadjuvant consolidation chemotherapy after CRT significantly increased the pCR rate and did not increase the AEs during and post treatment and in patients with LARC. creator: Jin Cui creator: Xue Dou creator: Yanlai Sun creator: Jinbo Yue uri: https://doi.org/10.7717/peerj.9513 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Cui et al. title: Safety evaluation of four faba bean extracts used as dietary supplements in grass carp culture based on hematological indices, hepatopancreatic function and nutritional condition link: https://peerj.com/articles/9516 last-modified: 2020-07-07 description: Faba bean (Vicia faba, FB) is known to improve the texture of fish meat but retards growth possibly by inducing hemolysis, hepatopancreas damage, and metabolic disorder. In this study, we used ultrasonic processing to isolate four FB extracts (water extract, alcohol extract, proteins and residues) and examined their beneficial and detrimental effects. These extracts were separately mixed with commercial feed and fed to grass carp (Ctenopharyngodon idellus) using whole FB and commercial feed as controls. After fish were fed one of the six experimental diets for 50 d and 100 d, we evaluated the growth and hematological parameters, activities of metabolic enzymes, hepatopancreatic histology and oxidative response, and lipid metabolism. Results showed that both whole FB and FB residues caused growth retardation and hepatopancreas damage (P < 0.05), whereas growth performance was improved in the FB water and alcohol extract groups compared to the whole FB group. Although the FB water extract negatively affected the number and morphological parameters of red blood cells (P < 0.05), the hematological damage was less pronounced than that of the whole FB group. Excessive hepatopancreatic fat accumulation was found in the whole FB, FB alcohol extract and FB residues groups. Moreover, serious hepatopancreas damages were observed in the FB residues group. These results suggest that the beneficial and detrimental components of FB were successfully separated in the four extracts, and the FB water extract would be the best choice for grass carp culture in terms of growth performance and health. The safety evaluation of the four FB extracts would facilitate further application of FB in aquatic feed. creator: Lingling Ma creator: Gen Kaneko creator: Jun Xie creator: Guangjun Wang creator: Zhifei Li creator: Jingjing Tian creator: Kai Zhang creator: Yun Xia creator: Wangbao Gong creator: Haihang Li creator: Ermeng Yu uri: https://doi.org/10.7717/peerj.9516 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Ma et al. title: Small molecule therapeutics for COVID-19: repurposing of inhaled furosemide link: https://peerj.com/articles/9533 last-modified: 2020-07-07 description: The novel coronavirus SARS-CoV-2 has become a global health concern. The morbidity and mortality of the potentially lethal infection caused by this virus arise from the initial viral infection and the subsequent host inflammatory response. The latter may lead to excessive release of pro-inflammatory cytokines, IL-6 and IL-8, as well as TNF-α ultimately culminating in hypercytokinemia (“cytokine storm”). To address this immuno-inflammatory pathogenesis, multiple clinical trials have been proposed to evaluate anti-inflammatory biologic therapies targeting specific cytokines. However, despite the obvious clinical utility of such biologics, their specific applicability to COVID-19 has multiple drawbacks, including they target only one of the multiple cytokines involved in COVID-19’s immunopathy. Therefore, we set out to identify a small molecule with broad-spectrum anti-inflammatory mechanism of action targeting multiple cytokines of innate immunity. In this study, a library of small molecules endogenous to the human body was assembled, subjected to in silico molecular docking simulations and a focused in vitro screen to identify anti-pro-inflammatory activity via interleukin inhibition. This has enabled us to identify the loop diuretic furosemide as a candidate molecule. To pre-clinically evaluate furosemide as a putative COVID-19 therapeutic, we studied its anti-inflammatory activity on RAW264.7, THP-1 and SIM-A9 cell lines stimulated by lipopolysaccharide (LPS). Upon treatment with furosemide, LPS-induced production of pro-inflammatory cytokines was reduced, indicating that furosemide suppresses the M1 polarization, including IL-6 and TNF-α release. In addition, we found that furosemide promotes the production of anti-inflammatory cytokine products (IL-1RA, arginase), indicating M2 polarization. Accordingly, we conclude that furosemide is a reasonably potent inhibitor of IL-6 and TNF-α that is also safe, inexpensive and well-studied. Our pre-clinical data suggest that it may be a candidate for repurposing as an inhaled therapy against COVID-19. creator: Zhiyu Wang creator: Yanfei Wang creator: Prachi Vilekar creator: Seung-Pil Yang creator: Mayuri Gupta creator: Myong In Oh creator: Autumn Meek creator: Lisa Doyle creator: Laura Villar creator: Anja Brennecke creator: Imindu Liyanage creator: Mark Reed creator: Christopher Barden creator: Donald F. Weaver uri: https://doi.org/10.7717/peerj.9533 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Wang et al. title: Intermittent theta burst stimulation facilitates functional connectivity from the dorsal premotor cortex to primary motor cortex link: https://peerj.com/articles/9253 last-modified: 2020-07-06 description: BackgroundMotor information in the brain is transmitted from the dorsal premotor cortex (PMd) to the primary motor cortex (M1), where it is further processed and relayed to the spinal cord to eventually generate muscle movement. However, how information from the PMd affects M1 processing and the final output is unclear. Here, we applied intermittent theta burst stimulation (iTBS) to the PMd to alter cortical excitability not only at the application site but also at the PMd projection site of M1. We aimed to determine how PMd iTBS–altered information changed M1 processing and the corticospinal output.MethodsIn total, 16 young, healthy participants underwent PMd iTBS with 600 pulses (iTBS600) or sham-iTBS600. Corticospinal excitability, short-interval intracortical inhibition (SICI), and intracortical facilitation (ICF) were measured using transcranial magnetic stimulation before and up to 60 min after stimulation.ResultsCorticospinal excitability in M1 was significantly greater 15 min after PMd iTBS600 than that after sham-iTBS600 (p = 0.012). Compared with that after sham-iTBS600, at 0 (p = 0.014) and 15 (p = 0.037) min after iTBS600, SICI in M1 was significantly decreased, whereas 15 min after iTBS600, ICF in M1 was significantly increased (p = 0.033).ConclusionOur results suggested that projections from the PMd to M1 facilitated M1 corticospinal output and that this facilitation may be attributable in part to decreased intracortical inhibition and increased intracortical facilitation in M1. Such a facilitatory network may inform future understanding of the allocation of resources to achieve optimal motion output. creator: Hai-Jiang Meng creator: Na Cao creator: Jian Zhang creator: Yan-Ling Pi uri: https://doi.org/10.7717/peerj.9253 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Meng et al. title: Melatonin improves the germination rate of cotton seeds under drought stress by opening pores in the seed coat link: https://peerj.com/articles/9450 last-modified: 2020-07-06 description: The germination of cotton (Gossypium hirsutum L.) seeds is affected by drought stress; however, little is known about the physiological mechanism affecting germination and the effect of melatonin (MT) on cotton seed germination under drought stress. Therefore, we studied the effects of exogenous MT on the antioxidant capacity and epidermal microstructure of cotton under drought stress. The results demonstrated a retarded water absorption capacity of testa under drought stress, significantly inhibiting germination and growth in cotton seeds. Drought stress led to the accumulation of reactive oxygen species (ROS), malondialdehyde (MDA), and osmoregulatory substances (e.g., proline, soluble protein, and soluble sugars); it also decreased the activity of antioxidant enzymes and α-amylase. Drought stress inhibited gibberellin acid (GA3) synthesis and increased abscisic acid (ABA) content, seriously affecting seed germination. However, seeds pre-soaked with MT (100 µM) showed a positive regulation in the number and opening of stomata in cotton testa. The exogenous application of MT increased the germination rate, germination potential, radical length, and fresh weight, as well as the activities of superoxide dismutase (SOD), peroxidase (POD), and α-amylase. In addition, MT application increased the contents of organic osmotic substances by decreasing the hydrogen peroxide (H2O2), superoxide anion (O2-), and MDA levels under drought stress. Further analysis demonstrated that seeds pre-soaked with MT alleviated drought stress by affecting the ABA and GA3 contents. Our findings show that MT plays a positive role in protecting cotton seeds from drought stress. creator: Yandan Bai creator: Shuang Xiao creator: Zichen Zhang creator: Yongjiang Zhang creator: Hongchun Sun creator: Ke Zhang creator: Xiaodan Wang creator: Zhiying Bai creator: Cundong Li creator: Liantao Liu uri: https://doi.org/10.7717/peerj.9450 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Bai et al. title: Rodents’ responses to manipulated plant litter and seed densities: implications for restoration link: https://peerj.com/articles/9465 last-modified: 2020-07-06 description: Rodent populations in arid grasslands do not always track seed production, possibly due to high levels of plant litter. When natural disturbances are suppressed, litter accumulates becoming physically complex, causing rodents to harvest fewer seeds per equivalent time foraging. It also alters security from predation. Restoring natural disturbances may be an important element in conserving rodent communities. The aim of this study was to assess the influence of two levels of plant litter cover and seed densities on nocturnal rodent population characteristics in a semiarid grassland. Specifically, I hypothesized that kangaroo rats, pocket mice, grasshopper mice, and total rodents would be higher in the sparse plant litter treatment than dense litter, whereas deer mice would be lower in sparse plots. I further hypothesized that kangaroo rats and deer mice would be higher in the seed augmented treatment compared to the unseeded treatment. A prescribed fire removed litter in four of eight plots prior to sowing native seeds 1 year postfire into two burned and two unburned plots. Rodents were live-trapped during spring and fall 1 year. Sparse litter treatment had higher total rodent abundance, biomass, and frequency of offspring compared to dense plots indicating use of stored seeds. Banner-tailed kangaroo rats had higher abundance, implying reduced predation risk. Pocket mice body mass was greater in dense plots. After winter, seeded plots had higher kangaroo rat body mass and grasshopper mice abundance than unseeded, reflecting the use of stored seeds. These short term results demonstrate litter’s physical complexity may be equivalent to seed pulses on the responses of nocturnal rodents. Managers might positively influence grassland rodents by providing a mosaic of varying levels of plant litter. creator: Nancy Nicolai uri: https://doi.org/10.7717/peerj.9465 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Nicolai