bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suv420 enrichment at the centromere limits Aurora B localization and function
Authors: Herlihy Conor P , Hahn Sabine , Hermance Nicole M , Crowley Elizabeth A , Manning Amity L 
Published: June 2021

AbstractCentromere structure and function are defined by the epigenetic modification of histones at centromeric and pericentromeric chromatin. The constitutive heterochromatin found at pericentromeric regions is highly enriched for H3K9me3 and H4K20me3. While mis-expression of the methyltransferase enzymes, Suv39 and Suv420, that regulate these marks are common in disease, the consequences of such changes are not well understood. Our data show that increased centromere localization of Suv39 and Suv420 suppress centromere transcription and compromise localization of the mitotic kinase Aurora B: decreasing microtubule dynamics and compromising chromosome alignment and segregation. We find that inhibition of Suv420 methyltransferase activity partially restores Aurora B localization to centromeres and that restoration of the Aurora B-containing CPC to the centromere is sufficient to suppress mitotic errors that result when Suv420/H4K20me3 is enriched at centromeres. Consistent with a role for Suv39 and Suv420 in negatively regulating Aurora B, high expression of these enzymes corresponds with increased sensitivity to Aurora kinase inhibition in cancer cells suggesting that increased H3K9 and H4K20 methylation may be an underappreciated source of chromosome missegregation in cancer.
The IL-33-ILC2 pathway protects from amebic colitis
Authors: Uddin Md Jashim , Leslie Jhansi L. , Burgess Stacey L. , Oakland Noah , Thompson Brandon , Abhyankar Mayuresh , Frisbee Alyse , Donlan Alexandra N , Kumar Pankaj , Petri William A 
Published: June 2021

AbstractEntamoeba histolytica is a pathogenic protozoan parasite that causes intestinal colitis, diarrhea, and in some cases, liver abscess. Through transcriptomics analysis, we observed that E. histolytica infection was associated with increased expression of IL-33 mRNA in both the human and murine colon. IL-33, the IL-1 family cytokine, is released after cell injury to alert the immune system of tissue damage during infection. Treatment with recombinant IL-33 protected mice from amebic infection and colonic tissue damage; moreover, blocking IL-33 signaling made mice more susceptible to infection and weight loss. IL-33 limited the recruitment of inflammatory immune cells and decreased the pro-inflammatory cytokine IL-6 in the colon. Type 2 immune responses, which are known to be involved in tissue repair, were upregulated by IL-33 treatment during amebic infection. Interestingly, administration of IL-33 protected RAG2-/- mice but not RAG2-/-γc-/- mice, demonstrating that IL-33 mediated protection occurred in the absence of T or B cells but required the presence of innate lymphoid cells (ILCs). IL-33 induced recruitment of ILC2 but not ILC1 and ILC3 in RAG2-/- mice. Adoptive transfer of ILC2s to RAG2-/-γc-/- mice restored IL-33 mediated protection. These data reveal that the IL-33-ILC2 pathway is an important host defense mechanism against amebic colitis.
Computational fluid dynamics provide evidence for a compensatory suction feeding like effect in the predatory strike of dragonfly larvae
Authors: Koehnsen Alexander , Brede Martin , Gorb Stanislav N , Büsse Sebastian 
Published: June 2021

AbstractMost fast-moving aquatic predators face the challenge of bow wave formation. Water in front of the predator alarms or even displaces the prey. To mitigate the formation of such a bow wave, a strategy aiming at pressure reduction via suction has evolved convergently in several animal groups: compensatory suction feeding. The aquatic larvae of dragonflies and damselflies (Insecta: Odonata) are likely to face this challenge as well. They capture prey underwater using a fast-moving raptorial appendage, the so-called prehensile labial mask. Within dragonflies (Odonata: Anisoptera) two basic shapes of the prehensile labial mask have evolved, with an either flat and slender or concave distal segment. While the former is a pure grasping device, the latter is also capable of scooping up smaller prey and retaining it inside the cavity by arrays of bristle-like structures. The hydrodynamics of the prehensile labial mask was previously unknown. We used computational fluid dynamic (CFD) simulations of the distal segment of the mask, to investigate for the first time how different shapes of the mask impact their function. Our results suggest that both shapes are highly streamlined and generate a low-pressure area, likely leading to an effect analogous to compensatory suction feeding. This presents a vivid example of how convergent evolution enables very different animal groups to successfully deal with the challenges of their environment. It may also be an interesting concept for technical application in small scale grasping devices; e.g. for simple sampling mechanisms in small-sized autonomous underwater vehicles (μAUVs).
Low-dose fluvoxamine modulates endocytic trafficking of SARS-CoV-2 spike protein: a potential mechanism for anti-COVID-19 protection by antidepressants
Authors: Glebov Oleg O 
Published: June 2021

AbstractCommonly prescribed antidepressants may be associated with protection against severe COVID-19, with one drug (fluvoxamine) currently undergoing a Phase 3 clinical trial. The mechanism of their action, however, remains unknown. Here, I investigated the effect of fluvoxamine on membrane trafficking of the SARS-CoV-2 spike protein and its cell host receptor ACE2 in HEK293T cells. A sub-therapeutic concentration (80 nM) of fluvoxamine rapidly upregulated fluid-phase endocytosis, resulting in enhanced accumulation of the spike-ACE2 complex in enlarged early endosomes. Diversion of endosomal trafficking may provide a simple cell biological mechanism consistent with the protective effect of antidepressants against COVID-19, highlighting their therapeutic and prophylactic potential.
Quantification of microRNA editing using two-tailed RT-qPCR for improved biomarker discovery
Authors: Voss Gjendine , Edsjö Anders , Bjartell Anders , Ceder Yvonne 
Published: June 2021

AbstractEven though microRNAs have been viewed as promising biomarkers for years, their clinical implementation is still lagging far behind. This is in part due to the lack of RT-qPCR technologies that can differentiate between microRNA isoforms. For example, A-to-I editing of microRNAs through adenosine deaminase acting on RNA (ADAR) enzymes can affect their expression levels and functional roles, but editing isoform-specific assays are not commercially available. Here, we describe RT-qPCR assays that are specific for editing isoforms, using microRNA-379 (miR-379) as a model. The assays are based on two-tailed RT-qPCR, and we show them to be compatible both with SYBR Green and hydrolysis-based chemistries, as well as with both qPCR and digital PCR. The assays could readily detect different miR-379 editing isoforms in various human tissues. We found that the miR-379 editing frequency was higher in prostate cancer samples compared to benign prostatic hyperplasia samples. Furthermore, decreased expression of unedited miR-379, but not edited miR-379, was associated with treatment resistance, metastasis and shorter overall survival. Taken together, this study presents the first RT-qPCR assays that were demonstrated to distinguish A-to-I-edited microRNAs, and shows that they can be useful in the identification of biomarkers that previously have been masked by other isoforms.Graphical abstract
RHBDL4 protects against endoplasmic reticulum stress by regulating the morphology and distribution of ER sheets
Authors: Lastun Viorica L. , Levet Clémence , Freeman Matthew 
Published: June 2021

AbstractIn metazoans, the architecture of the endoplasmic reticulum (ER) differs between cell types, and undergoes major changes through the cell cycle and according to physiological needs. Although much is known about how the different ER morphologies are generated and maintained, especially the ER tubules, how context dependent changes in ER shape and distribution are regulated and the factors involved are less characterized. Here, we show that RHBDL4, an ER-resident rhomboid protease, modulates the shape and distribution of the ER, especially under conditions that require rapid changes in the ER sheet distribution, including ER stress. RHBDL4 interacts with CLIMP-63, a protein involved in ER sheet stabilisation, and with the cytoskeleton. Mice lacking RHBDL4 are sensitive to ER stress and develop liver steatosis, a phenotype associated with unresolved ER stress. Our data introduce a new physiological role of RHBDL4 and also imply that this function does not require its enzymatic activity.
Complete metamorphosis and microbiota turnover in insects
Authors: Manthey Chrisitin , Johnston Paul , Rolff Jens 
Published: June 2021

AbstractThe insects constitute the majority of animal diversity. Most insects are holometabolous: during complete metamorphosis their bodies are radically re-organized. This re-organization poses a significant challenge to the gut microbiota, as the gut is replaced during pupation, a process that does not occur in hemimetabolous insects. In holometabolous hosts, it offers the opportunity to decouple the gut microbiota between the larval and adult life stages resulting in high beta diversity whilst limiting alpha diversity. Here we studied 18 different herbivorous insect species from 5 orders of holometabolous and 3 orders of hemimetabolous insects. Comparing larval and adult specimens, we find a much higher beta-diversity and hence microbiota turnover in holometabolous insects compared to hemimetabolous insects. Alpha diversity did not differ between holo-and hemimetabolous insects nor between developmental stages within these groups. Our results support the idea that pupation offers the opportunity to change the gut microbiota and hence facilitates ecological niche shifts. This effect of niche shift facilitation could explain a selective advantage of the evolution of complete metamorphosis, which is a defining trait of the most speciose insect taxon, the holometabola.
The SARS-CoV-2 nucleocapsid protein associates with the replication organelles before viral assembly at the Golgi/ERGIC and lysosome-mediated egress
Authors: Scherer Katharina M. , Mascheroni Luca , Carnell George W. , Wunderlich Lucia C. S. , Makarchuk Stanislaw , Brockhoff Marius , Mela Ioanna , Fernandez-Villegas Ana , Barysevich Max , Stewart Hazel , Sans Maria Suau , George Charlotte L. , Lamb Jacob R. , Kaminski-Schierle Gabriele S. , Heeney Jonathan L. , Kaminski Clemens F. 
Published: June 2021

AbstractDespite being the target of extensive research efforts due to the COVID-19 pandemic, relatively little is known about the dynamics of SARS-CoV-2 replication within cells. We investigate and characterise the tightly orchestrated sequence of events during different stages of the infection cycle by visualising the spatiotemporal dynamics of the four structural proteins of SARS-CoV-2 at high resolution. The nucleoprotein is expressed first and accumulates around folded ER membranes in convoluted layers that connect to viral RNA replication foci. We find that of the three transmembrane proteins, the membrane protein appears at the Golgi apparatus/ERGIC before the spike and envelope proteins. Relocation of the lysosome marker LAMP1 towards the assembly compartment and its detection in transport vesicles of viral proteins confirm an important role of lysosomes in SARS-CoV-2 egress. These data provide new insights into the spatiotemporal regulation of SARS-CoV-2 assembly, and refine current understanding of SARS-CoV-2 replication.
Tensor Decomposition-based Unsupervised Feature Extraction Succeeded in Identification of Differentially Expressed Transcripts from Redundantde novoTranscriptome ofPlanarian
Authors: Kashima Makoto , Kumagai Nobuyoshi , Hirata Hiromi , Taguchi Y-h. 
Published: June 2021

AbstractRNA-Seq data analysis of non-model organisms is often difficult because of the lack of a well-annotated genome. However, in non-model organisms, contigs can be generated byde novoassembling. This can result in a large number of transcripts, making it difficult to easily remove redundancy. A large number of transcripts can also lead to difficulty in the recognition of differentially expressed transcripts (DETs) between more than two experimental conditions, becauseP-values must be corrected by considering multiple comparison corrections whose effect is enhanced as the number of transcripts increases. Heavily correctedP-values often fail to take sufficiently smallP-values as significant. In this study, we applied a recently proposed tensor decomposition (TD)-based unsupervised feature extraction (FE) to the RNA-seq data obtained for a non-model organism, planarianDugesia japonica; Although we used de novo assembled transcriptome reference with high redundancy, we successfully obtained a larger number of transcripts whose expression was altered between normal and defective samples as well as during time development than those identified by a conventional method. TD-based unsupervised FE is expected to be an effective tool that can identify a substantial number of DETs, even when a poorly annotated genome is available.
Revisiting the service recovery paradox in the restaurant industry
Authors: Kim Jong-Hyeong , Du Wenxuan , Youn Hyewon 
Published: June 2021

PurposeThe service recovery paradox (SRP) refers to a particular effect whereby an excellent recovery can turn angry and frustrated customers into loyal ones. Researchers who have studied the SRP have reported mixed findings, with some providing evidence in its support and others not finding any such evidence. To address this discrepancy, this study aims to investigate the SRP.Design/methodology/approachThis study re-examined the phenomenon of the SRP with a field study and provided further evidence in a subsequent experimental study in which the failure and recovery conditions were carefully manipulated.FindingsThe results of this study suggest that the SRP was observed in neither the field study nor the scenario experiment.Practical implicationsThis study can influence the current service management of restaurants with regard to service failures in several ways.Originality/valueThis research is a pioneering effort to examine the SRP by conducting both a field study and a scenario experiment.
An institutional approach to the development of business angel networks in Latin American emerging countries
Authors: Martins Izaias , Romaní Gianni , Atienza Miguel 
Published: June 2021

Purpose
The purpose of the paper is to analyze the development of business angel networks (BANs) in emerging countries such as Chile and Colombia to understand how institutions affect their development.

Design/methodology/approach
This is a qualitative, exploratory, and descriptive study based on a comparative analysis between countries, with the BANs in Chile and Colombia as the unit of observation. The comparative analysis was made in relation with the creation, operation and sustainability of the BANs. The study interviews the partners/managers of the active networks in each of the countries, as well as key informants, totalling 12 interviews.

Findings
BAN activity in Chile and Colombia is quite recent, and the countries are on a similar level of development. However, in the long term, depending on how the cultural aspects evolve in both countries and the interest that the State may have in developing business angel activity, the results could be indeed different.

Originality/value
Business angel activity in Latin America is quite recent; nevertheless, this activity is increasing in the region. In that sense, this comparative analysis between Colombia and Chile contributes to a better understanding of business angel markets in Latin America and also to obtain better insights into the core challenges that these markets face in emerging countries due to the existence of institutional voids. This paper is a contribution for further knowledge of BANs in emerging countries’ economies from an institutional perspective.
Topological sensitivity analysis with respect to a small idealized bolt
Authors: Rakotondrainibe Lalaina , Allaire Grégoire , Orval Patrick 
Published: June 2021

PurposeThis paper is devoted to the theoretical and numerical study of a new topological sensitivity concerning the insertion of a small bolt connecting two parts in a mechanical structure. First, an idealized model of bolt is proposed which relies on a non-local interaction between the two ends of the bolt (head and threads) and possibly featuring a pre-stressed state. Second, a formula for the topological sensitivity of such an idealized bolt is rigorously derived for a large class of objective functions. Third, numerical tests are performed in 2D and 3D to assess the efficiency of the bolt topological sensitivity in the case of no pre-stress. In particular, the placement of bolts (acting then as springs) is coupled to the further optimization of their location and to the shape and topology of the structure for volume minimization under compliance constraint.Design/methodology/approachThe methodology relies on the adjoint method and the variational formulation of the linearized elasticity equations in order to establish the topological sensitivity.FindingsThe numerical results prove the influence of the number and locations of the bolts which strongly influence the final optimized design of the structure.Originality/valueThis paper is the first one to study the topology optimization of bolted systems without a fixed prescribed number of bolts.
Knowledge base, technology gap and technology development speed in technological catch-up: innovation choice for China's knowledge-intensive enterprises (KIEs)
Authors: Zhang Zhengyi , Jin Jun , Wen Ting , Chen Zan 
Published: June 2021

PurposeWith the fierce competition in a knowledge economy, knowledge-intensive enterprises (KIEs) make technological progress in their catching-up processes through implementing product innovation and process innovation. In this study, the aim is to understand the determinants of enterprise innovation type in China's catch-up environment. Further, this paper intends to deal with two related questions. First, what effect does the internal knowledge base have on KIEs' technology innovation activities? Second, considering the technology gap and technology development speed, what are the different impacts of the knowledge base on the type of technology innovation activities?Design/methodology/approachThis paper collected data from 212 KIEs in China through a two-stage questionnaire survey, combined with statistical data for research. The hypothesis was tested by regression analysis. Specifically, descriptive statistics and regression analysis are introduced to test the hypothetical relationship between the knowledge base and technology innovation. Meanwhile, multiple regression is used to test whether there is any difference in the influence of technology gap and technology development speed on enterprise knowledge base and technology innovation. Finally, the corresponding robustness tests are done.FindingsThis study finds that in a sample of Yangtze River Delta KIEs, firms' knowledge base influences innovation types. Specifically, the knowledge base width (KBW) and knowledge base depth (KBD) positively influence process innovation, and KBD positively affects product innovation. Regarding the effects of catch-up context factors on KIEs’ innovation choice, a wide technology gap tends to positively influence product innovation in industries with high levels of KBW. Moreover, when technology development speed is high, its potential positive influence on process innovation will be more significant for industries with deeper knowledge bases.Originality/valueThis paper fills the research gap that existing studies ignore the relationship between types of technology innovation and knowledge base dimensions, especially for KIEs. First, this paper deepens the understanding of the impact mechanism of KIEs' existing knowledge base on innovation activities; the unique use of resources by enterprises is the basis of enterprises' competitive advantage and will become enterprises' competitive advantage. Second, this study indicates that against different backdrops of technology gap and technology development speed, enterprises with different knowledge bases will adopt different types of technology innovation activities. Third, this paper shows that a wider technology gap provides broader innovation space, so the technology gap plays a pulling role in KBW and product innovation, thus pushing forward enterprises' technological catch-up.
A hierarchal model of coding knowledge towards facilitating knowledge transfer in organizations
Authors: Valmohammadi Changiz , Rahmani Farzaneh 
Published: June 2021

Purpose
This paper aims to present a hierarchal and operational model of coding knowledge towards facilitating the transformation of knowledge in organizations.

Design/methodology/approach
The methodology used, is based on collaborative participation in knowledge coding that is widely used in large settings such as Wikipedia.

Findings
Knowledge coding means the transfer of knowledge into a model which can be stored and shared. According to this definition, Knowledge can be accepted as a set of facts and the relationships among them. Through the suggested hierarchical model, primarily facts and initial entities are determined and knowledge record begins with the start of recording routines. In general, each routine is made up of simpler routines and facts. Thus the final model, which is a set of compound and complicated routines, can encode different levels of knowledge with different complexities. The suggested model in the explained processes is a conceptual model and a descriptive model in explaining facts.

Research limitations/implications
Due to high-level programming expertise, in this paper, only the method of implementation of the proposed operational model has been explained. The proposed method maintains various advantages such as applicability, comprehensibility by different people in an organization, the possibility of knowledge coding at different levels, supporting abstract concepts besides operational ones and finally the possibility of implementing it by existing tools.

Practical implications
The suggested model can be used for a variety of needs. For instance, in this paper, the first modelling example referred to a software concept, while the other referred to the implementation of an organizational process. Due to a hierarchy in describing knowledge, the suggested model can be used by any user with any level of knowledge (either user or registrar).

Social implications
This method can create a change in social media and make it possible for anyone in any society with any level of information to share their knowledge at their own level and use the knowledge of others at the same level.

Originality/value
The strength of the proposed model stems from its hierarchical nature which is considered for knowledge coding at different levels and includes advantages such as comprehensibility for different people in an organization, the possibility of knowledge coding at different levels and supporting abstract concepts in addition to operational ones.