title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=616 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Stroke-related length of hospitalization trends and in-hospital mortality in Peru link: https://peerj.com/articles/14467 last-modified: 2022-11-25 description: BackgroundPeru faces challenges to provide adequate care to stroke patients. Length of hospitalization and in-hospital mortality are two well-known indicators of stroke care. We aimed to describe the length of stay (LOS) of stroke in Peru, and to assess in-hospital mortality risk due to stroke, and subtypes.MethodsThis retrospective cohort study used hospitalization registries coding with ICD-10 from 2002 to 2017 (N = 98,605) provided by the Ministry of Health; in-hospital mortality was available for 2016–2017 (N = 6,566). Stroke cases aged ≥35 years were divided into subarachnoid hemorrhage (I60), intracerebral hemorrhage (I61), cerebral infarction (I63), and stroke not specified as hemorrhage or infarction (I64). Data included stroke LOS and in-hospital mortality; socio-demographic and clinical variables. We fitted a region- and hospital level-stratified Weibull proportional hazard model to assess the in-hospital mortality.ResultsThe median LOS was 7 days (IQR: 4–13). Hemorrhagic strokes had median LOS longer than ischemic strokes and stroke not specified as hemorrhage or infarction (P = <0.001). The case fatality rate (CFR) of patients with stroke was 11.5% (95% CI [10–12%]). Subarachnoid hemorrhage (HR = 2.45; 95% CI [1.91–3.14]), intracerebral hemorrhage (HR = 1.95; 95% CI [1.55–2.46]), and stroke not specified as hemorrhage or infarction (HR = 1.45; 95% CI [1.16–1.81]) were associated with higher in-hospital mortality risk in comparison to ischemic strokes.DiscussionBetween 2002 and 2017, LOS due to stroke has not changed in Peru in stroke patients discharged alive. Hemorrhagic cases had the longest LOS and highest in-hospital mortality risk during 2016 and 2017. The findings of our study seem to be consistent with a previous study carried out in Peru and similar to that of HIC and LMIC, also there is an increased median LOS in stroke cases managed in specialized centers. Likewise, LOS seems to depend on the type of stroke, where ischemic stroke cases have the lowest LOS. Peru needs to improve access to stroke care. creator: L. Max Labán-Seminario creator: Rodrigo M. Carrillo-Larco creator: Antonio Bernabé-Ortiz uri: https://doi.org/10.7717/peerj.14467 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Labán-Seminario et al. title: No evidence for asymmetric sperm deposition in a species with asymmetric male genitalia link: https://peerj.com/articles/14225 last-modified: 2022-11-24 description: BackgroundAsymmetric genitalia have repeatedly evolved in animals, yet the underlying causes for their evolution are mostly unknown. The fruit fly Drosophila pachea has asymmetric external genitalia and an asymmetric phallus with a right-sided phallotrema (opening for sperm release). The complex of female and male genitalia is asymmetrically twisted during copulation and males adopt a right-sided copulation posture on top of the female. We wished to investigate if asymmetric male genital morphology and a twisted gentitalia complex may be associated with differential allocation of sperm into female sperm storage organs.MethodsWe examined the internal complex of female and male reproductive organs by micro-computed tomography and synchrotron X-ray tomography before, during and after copulation. In addition, we monitored sperm aggregation states and timing of sperm transfer during copulation by premature interruption of copulation at different time-points.ResultsThe asymmetric phallus is located at the most caudal end of the female abdomen during copulation. The female reproductive tract, in particular the oviduct, re-arranges during copulation. It is narrow in virgin females and forms a broad vesicle at 20 min after the start of copulation. Sperm transfer into female sperm storage organs (spermathecae) was only in a minority of examined copulation trials (13/64). Also, we found that sperm was mainly transferred early, at 2–4 min after the start of copulation. We did not detect a particular pattern of sperm allocation in the left or right spermathecae. Sperm adopted a granular or filamentous aggregation state in the female uterus and spermathecae, respectively.DiscussionNo evidence for asymmetric sperm deposition was identified that could be associated with asymmetric genital morphology or twisted complexing of genitalia. Male genital asymmetry may potentially have evolved as a consequence of a complex internal alignment of reproductive organs during copulation in order to optimize low sperm transfer rates. creator: Sanne van Gammeren creator: Michael Lang creator: Martin Rücklin creator: Menno Schilthuizen uri: https://doi.org/10.7717/peerj.14225 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 van Gammeren et al. title: A multi-reference poly-conformational method for in silico design, optimization, and repositioning of pharmaceutical compounds illustrated for selected SARS-CoV-2 ligands link: https://peerj.com/articles/14252 last-modified: 2022-11-24 description: BackgroundThis work presents a novel computational multi-reference poly-conformational algorithm for design, optimization, and repositioning of pharmaceutical compounds.MethodsThe algorithm searches for candidates by comparing similarities between conformers of the same compound and identifies target compounds, whose conformers are collectively close to the conformers of each compound in the reference set. Reference compounds may possess highly variable MoAs, which directly, and simultaneously, shape the properties of target candidate compounds.ResultsThe algorithm functionality has been case study validated in silico, by scoring ChEMBL drugs against FDA-approved reference compounds that either have the highest predicted binding affinity to our chosen SARS-CoV-2 targets or are confirmed to be inhibiting such targets in-vivo. All our top scoring ChEMBL compounds also turned out to be either high-affinity ligands to the chosen targets (as confirmed in separate studies) or show significant efficacy, in-vivo, against those selected targets. In addition to method case study validation, in silico search for new compounds within two virtual libraries from the Enamine database is presented. The library’s virtual compounds have been compared to the same set of reference drugs that we used for case study validation: Olaparib, Tadalafil, Ergotamine and Remdesivir. The large reference set of four potential SARS-CoV-2 compounds has been selected, since no drug has been identified to be 100% effective against the virus so far, possibly because each candidate drug was targeting only one, particular MoA. The goal here was to introduce a new methodology for identifying potential candidate(s) that cover multiple MoA-s presented within a set of reference compounds. creator: Vadim Alexandrov creator: Alexander Kirpich creator: Omar Kantidze creator: Yuriy Gankin uri: https://doi.org/10.7717/peerj.14252 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Alexandrov et al. title: Mislabeling and nomenclatorial confusion of Typhlotanais sandersi Kudinova-Pasternak, 1985 (Crustacea: Tanaidacea) and establishment of a new genus link: https://peerj.com/articles/14272 last-modified: 2022-11-24 description: Re-examination of historical collections allowed us to resolve the taxonomic status of Typhlotanais sandersi Kudinova-Pasternak, 1985, originally described based on a single specimen from Great-Meteor Seamount. The holotype of this species was considered lost and the species redescribed based on a second specimen from the type locality by Błażewicz-Paszkowycz (2007a), who placed Ty. sandersi on a newly established genus Typhlamia. Thorough morphological analysis of Typhlamia and Typhlotanais species and recently obtained genetic data of typhlotanaids from N Atlantic and NW Pacific waters allow us to conclude that the redescription of Ty. sandersi by Błażewicz-Paszkowycz (2007a) was based on a wrongly labelled specimen that, rather than a type of Ty. sandersi, represents in fact a new species of Typhlamia. The morphological comparison of the type species of Typhlotanais (Ty. aequiremis) with all ‘long-bodied’ typhlotanaid taxa with rounded pereonites margins (i.e., Typhlamia, Pulcherella, Torquella), and the use of genetic evidence, support the establishment of a new genus to accommodate: Ty. sandersi, Ty. angustichelesKudinova-Pasternak, 1989, and a third species from N Atlantic waters, that is described here for the first time. Current knowledge on ‘long-bodied’ typhlotanaids with rounded pereonites is summarised and a taxonomical key for their identification provided. creator: Marta Gellert creator: Ferran Palero creator: Magdalena Błażewicz uri: https://doi.org/10.7717/peerj.14272 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Gellert et al. title: Effects of motor imagery training on skeletal muscle contractile properties in sports science students link: https://peerj.com/articles/14412 last-modified: 2022-11-24 description: BackgroundStudies on motor imagery (MI) practice based on different designs and training protocols have reported changes in maximal voluntary contraction (MVC) strength. However, to date, there is a lack of information on the effects of MI training on contractile properties of the trained muscle.MethodsForty-five physically active sport science students (21 female) were investigated who trained three times per week over a 4-week period in one of three groups: An MI group conducted MI practice of maximal isometric contraction of the biceps brachii; a physical exercise (PE) group physically practiced maximal isometric contractions of the biceps brachii in a biceps curling machine; and a visual imagery (VI) group performed VI training of a landscape. A MVC test of the arm flexors was performed in a biceps curling machine before and after 4 weeks of training. The muscular properties of the biceps brachii were also tested with tensiomyography measurements (TMG).ResultsResults showed an interaction effect between time and group for MVC (p = 0.027, η2 = 0.17), with a higher MVC value in the PE group (Δ5.9%) compared to the VI group (Δ −1.3%) (p = 0.013). MVC did not change significantly in the MI group (Δ2.1%). Analysis of muscle contractility via TMG did not show any interaction effects neither for maximal radial displacement (p = 0.394, η2 = 0.05), delay time (p = 0.79, η2 = 0.01) nor contraction velocity (p = 0.71, η2 = 0.02).ConclusionIn spite of MVC-related changes in the PE group due to the interventions, TMG measurements were not sensitive enough to detect concomitant neuronal changes related to contractile properties. creator: Björn Wieland creator: Michael Behringer creator: Karen Zentgraf uri: https://doi.org/10.7717/peerj.14412 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Wieland et al. title: Evidence for stronger discrimination between conspecific and heterospecific mating partners in sexual vs. asexual female freshwater snails link: https://peerj.com/articles/14470 last-modified: 2022-11-24 description: Once-useful traits that no longer contribute to fitness tend to decay over time. Here, we address whether the expression of mating-related traits that increase the fitness of sexually reproducing individuals but are likely less useful or even costly to asexual counterparts seems to exhibit decay in the latter. Potamopyrgus antipodarum is a New Zealand freshwater snail characterized by repeated transitions from sexual to asexual reproduction. The frequent coexistence of sexual and asexual lineages makes P. antipodarum an excellent model for the study of mating-related trait loss. Under the presumption (inherent in the Biological Species Concept) that failure to discriminate between conspecific and heterospecific mating partners represents a poor mate choice, we used a mating choice assay including sexual and asexual P. antipodarum females and conspecific (presumed better choice) vs. heterospecific (presumed worse choice) males to evaluate the loss of behavioral traits related to sexual reproduction. We found that sexual females engaged in mating behaviors with conspecific mating partners more frequently and for a greater duration than with heterospecific mating partners. By contrast, asexual females mated at similar frequency and duration as sexual females, but did not mate more often or for longer duration with conspecific vs. heterospecific males. While further confirmation will require inclusion of a more diverse array of sexual and asexual lineages, these results are consistent with a scenario where selection acting to maintain effective mate discrimination in asexual P. antipodarum is weak or ineffective relative to sexual females and, thus, where asexual reproduction is associated with the evolutionary decay of mating-related traits in this system. creator: Sydney Stork creator: Joseph Jalinsky creator: Maurine Neiman uri: https://doi.org/10.7717/peerj.14470 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Stork et al. title: Evaluation of film stimuli for the assessment of social-emotional processing: a pilot study link: https://peerj.com/articles/14160 last-modified: 2022-11-23 description: BackgroundDifficulties in top-down and bottom-up emotion generation have been proposed to play a key role in the progression of psychiatric disorders. The aim of the current study was to develop more ecologically valid measures of top-down interpretation biases and bottom-up evoked emotional responses.MethodsA total of 124 healthy female participants aged 18–25 took part in the study. We evaluated two sets of 18 brief film clips. The first set of film clips presented ambiguous social situations designed to examine interpretation biases. Participants provided written interpretations of each ambiguous film clip which were subjected to sentiment analysis. We compared the films in terms of the valence of participants interpretations. The second set of film clips presented neutral and emotionally provoking social scenarios designed to elicit subjective and facial emotional responses. While viewing these film clips participants mood ratings and facial affect were recorded and analysed using exploratory factor analyses.ResultsMost of the 18 ambiguous film clips were interpreted in the expected manner while still retaining some ambiguity. However, participants were more attuned to the negative cues in the ambiguous film clips and three film clips were identified as unambiguous. These films clips were deemed unsuitable for assessing interpretation bias. The exploratory factor analyses of participants’ mood ratings and evoked facial affect showed that the positive and negative emotionally provoking film clips formed their own factors as expected. However, there was substantial cross-loading of the neutral film clips when participants’ facial expression data was analysed.DiscussionA subset of the film clips from the two tasks could be used to assess top-down interpretation biases and bottom-up evoked emotional responses. Ambiguous negatively valenced film clips should have more subtle negative cues to avoid ceiling effects and to ensure there is enough room for interpretation. creator: Jenni Leppanen creator: Olivia Patsalos creator: Sophie Surguladze creator: Jess Kerr-Gaffney creator: Steven Williams creator: Ketevan Tchanturia uri: https://doi.org/10.7717/peerj.14160 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Leppanen et al. title: Comprehensive proteomic and metabolomic analysis uncover the response of okra to drought stress link: https://peerj.com/articles/14312 last-modified: 2022-11-23 description: The response of okra to drought stress is very complicated, and the molecular mechanisms underlying this process remains ambiguous up to now. In this study, different degrees of water-stress responses of okra leaf were explained by using transcriptomics and metabolomic approaches. The photosynthesis and glycometabolism in okra leaf were both adversely affected by drought stress, leading to inhibition of the carbohydrate metabolic process, and then influencing the secondary plant metabolism. Further, drought stress disturbed amino acid metabolism, especially for the tyrosine-derived pathway as well as arginine and proline metabolism, which have been shown to be significantly enriched under water withholding conditions based on multi-omics conjoint analysis (transcriptome, proteome and metabolome). In-depth analysis of the internal linkages between differentially expressed transcripts, proteins, and metabolites decidedly indicate that tyrosine metabolism could confer tolerance to drought stress by influencing carbon and nitrogen metabolism. These findings provide a whole framework of the regulation and relationships of major transcripts and peptides related to secondary metabolism, particularly, the role of critical proteins and metabolite involved in the change of amino acid metabolism in response to drought stress. creator: Jiyue Wang creator: Denghong Shi creator: Yu Bai creator: Ting Zhang creator: Yan Wu creator: Zhenghong Liu creator: Lian Jiang creator: Lin Ye creator: Zele Peng creator: Hui Yuan creator: Yan Liu uri: https://doi.org/10.7717/peerj.14312 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Wang et al. title: Targeting fibroblast growth factor receptors causes severe craniofacial malformations in zebrafish larvae link: https://peerj.com/articles/14338 last-modified: 2022-11-23 description: Background and ObjectiveA key pathway controlling skeletal development is fibroblast growth factor (FGF) and FGF receptor (FGFR) signaling. Major regulatory functions of FGF signaling are chondrogenesis, endochondral and intramembranous bone development. In this study we focus on fgfr2, as mutations in this gene are found in patients with craniofacial malformations. The high degree of conservation between FGF signaling of human and zebrafish (Danio rerio) tempted us to investigate effects of the mutated fgfr2sa10729 allele in zebrafish on cartilage and bone formation.MethodsWe stained cartilage and bone in 5 days post fertilization (dpf) zebrafish larvae and compared mutants with wildtypes. We also determined the expression of genes related to these processes. We further investigated whether pharmacological blocking of all FGFRs with the inhibitor BGJ398, during 0–12 and 24–36 h post fertilization (hpf), affected craniofacial structure development at 5 dpf.ResultsWe found only subtle differences in craniofacial morphology between wildtypes and mutants, likely because of receptor redundancy. After exposure to BGJ398, we found dose-dependent cartilage and bone malformations, with more severe defects in fish exposed during 0–12 hpf. These results suggest impairment of cranial neural crest cell survival and/or differentiation by FGFR inhibition. Compensatory reactions by upregulation of fgfr1a, fgfr1b, fgfr4, sp7 and dlx2a were found in the 0–12 hpf group, while in the 24–36 hpf group only upregulation of fgf3 was found together with downregulation of fgfr1a and fgfr2.ConclusionsPharmacological targeting of FGFR1-4 kinase signaling causes severe craniofacial malformations, whereas abrogation of FGFR2 kinase signaling alone does not induce craniofacial skeletal abnormalities. These findings enhance our understanding of the role of FGFRs in the etiology of craniofacial malformations. creator: Liesbeth Gebuijs creator: Frank A. Wagener creator: Jan Zethof creator: Carine E. Carels creator: Johannes W. Von den Hoff creator: Juriaan R. Metz uri: https://doi.org/10.7717/peerj.14338 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Gebuijs et al. title: Augmented anticancer effect and antibacterial activity of silver nanoparticles synthesized by using Taxus wallichiana leaf extract link: https://peerj.com/articles/14391 last-modified: 2022-11-23 description: BackgroundTaxus wallichiana is an evergreen tree species found in the Himalayan region of Pakistan. The tree possesses important secondary metabolites such as Taxol that has been implicated in treating breast, ovarian and colon cancer. Therefore keeping in view the importance of this plant species, silver nanoparticles were synthesized using Taxus wallichiana aqueous leaf extract and evaluated for their anti-bacterial and anti-cancer properties.MethodsSilver (Ag) nanoparticles (NPs) were characterized for their optical, morphological and structural features using techniques such as UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) and were evaluated for their antibacterial activity and anti-cancer activity using U251 cell line.ResultsThe study showed that the UV-absorbance peak of Ag2O NPs at 450 nm shifted to 410 nm, affirming the formation of leaf extract Ag NPs. Similarly structural studies revealed the crystalline nature of the cubic structure of the Ag crystal with an average crystallite size of 29 nm. FTIR analysis exhibited the existence of different functional elements including O-H and N-H and phenolic groups. Non-spherical glomerular shaped Taxus wallichiana Ag NPs were observed from SEM studies and EDX profile showed Ag as the main element along with constituent of biological origin. The synthesized Ag NPs showed significant antibacterial activity against Salmonella typhi, and Staphylococcus aureus. The cytotoxic activity of Ag NPs on U251 brain cancer cells showed a synergistic effect with 10 ug/mL concentration after 48 and 72 h incubation based on cell viability assay indicating promising glioblastoma drug potential. creator: Aliya Yousaf creator: Muhammad Waseem creator: Aneela Javed creator: Sofia Baig creator: Bushra Ismail creator: Ayesha Baig creator: Irum Shahzadi creator: Shamyla Nawazish creator: Iftikhar Zaman uri: https://doi.org/10.7717/peerj.14391 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Yousaf et al.