bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and Validation of Psychometric Properties of the 10 IB Learner Profile Instrument (10IBLP-I): A Combination of the Rasch and Classical Measurement Model
Authors: Kamaruddin Miftahuljanah , Mohd Matore Mohd
Published: June 2021

Background: The International Baccalaureate Middle Years Programme (IBMYP) aims to produce a holistic transformation with creative and critically minded students. However, very little attention has been paid to the development of an instrument to measure the IB learner profile with good psychometric properties. Purpose: This study aims to develop an instrument with good psychometric properties, based on the Rasch measurement model and confirmatory factor analysis. Methods: The study consists of two phases of pilot and field studies involving 597 year four students from IBWS MOE. Results: The findings from the Rasch measurement model analysis have shown that 54 items meet the criteria of the item fit, unidimensionality, and reliability index. Meanwhile, confirmatory factor analysis found that 44 items have shown a valid item fit index. Conclusions: The combination of both analyses has shown the strength of 10IBLP-I psychometric properties that cover the aspects of validity and reliability. The findings also provide an implication to the theory, with empirical evidence that the IB learner profile consists of 10 constructs. Besides, the evidenced 10IBLP-I comprises good psychometric properties, which can be used to measure the level of IB learner profile among IBWS MOE students to assess the effectiveness of the implementation of IBMYP in Malaysia.
Virtual Experience of Perioperative Patients: Walking in the Patients’ Shoes Using Virtual Reality and Blended Learning
Authors: Kim Hyeon-Young , Lee Ji-Hye , Lee Eun-Hye
Published: June 2021

PURPOSE: This study examined the significance, nature, and structure of the virtual experience of perioperative patients as undergone by nursing students during their practical training through VR and blended learning. METHODS: Data were collected through a focus group interview (FGI) of 21 nursing student participants from November 2019 to December 2019 and analyzed through Colaizzi’s phenomenological method. RESULTS: Seven theme clusters were organized that described nursing students’ experiences. They are “placed in a passive position,” “facing the limits of communication,” “thinking of developing and improving competency as a nurse,” “recognizing the importance of interacting with their patients”, “learning vividly through experience”, “engaging in a new type of participatory learning”, and “designing nursing knowledge.” CONCLUSION: Patient-centered care can be achieved in the nursing school curriculum through “patient experiences.” Additionally, the feedback from research participants who have “become keenly aware of the need for patient experiences” shows that empathizing with the “patient experience” is an essential quality to acquire by prospective medical professionals before they are introduced to the nursing field. We suggest future studies that expand on nursing students’ patient experience in various teaching methods and curriculums.
Repurposing an EMG Biofeedback Device for Gait Rehabilitation: Development, Validity and Reliability
Authors: Koiler Reza , Bakhshipour Elham , Glutting Joseph , Lalime Amy , Kofa Dexter , Getchell Nancy
Published: June 2021

Gait impairment often limits physical activity and negatively impacts quality of life. EMG-Biofeedback (EMG-BFB), one of the more effective interventions for improving gait impairment, has been limited to laboratory use due to system costs and technical requirements, and has therefore not been tested on a larger scale. In our research, we aimed to develop and validate a cost-effective, commercially available EMG-BFB device for home- and community-based use. We began by repurposing mTrigger® (mTrigger LLC, Newark, DE, USA), a cost-effective, portable EMG-BFB device, for gait application. This included developing features in the cellphone app such as step feedback, success rate, muscle activity calibration, and cloud integration. Next, we tested the validity and reliability of the mTrigger device in healthy adults by comparing it to a laboratory-grade EMG system. While wearing both devices, 32 adults walked overground and on a treadmill at four speeds (0.3, 0.6, 0.9, and 1.2 m/s). Statistical analysis revealed good to excellent test–retest reliability (r > 0.89) and good to excellent agreement in the detection of steps (ICC > 0.85) at all speeds between two systems for treadmill walking. Our results indicated that mTrigger compared favorably to a laboratory-grade EMG system in the ability to assess muscular activity and to provide biofeedback during walking in healthy adults.
A Model for Strengthening Mentors: Frames and Practices
Authors: Blake-Beard Stacy , Shapiro Mary , Ingols Cynthia
Published: June 2021

The extensive body of literature on mentoring has largely ignored the developmental needs of mentors themselves. This conceptual and practice-oriented paper asks mentors and others to consider the needs of mentors who may or may not arrive ready to deal with the challenges of being effective mentors. The authors ask: how should mentors think about their own growth and development? Drawing on a broad spectrum of academic literatures, three frames are proposed for guiding mentors’ thinking about themselves and four practices to spur their continuous improvement. The three frames are a simultaneous dual focus on people and tasks as mentors exercise leadership; an inclusive mind-set that works across the multidimensionality of identities in others and themselves; and a keen sense of the threats and rewards of managing the perceptions of others. We recommend the use of four practices for self-examination: engage in structured self-reflection; participate in standardized assessments to see others and one’s self differently; build peer support among colleagues; and ask for feedback in concrete terms. We conclude by offering the benefits and challenges as mentors engage in the difficult work of acquiring in-depth self-awareness.
Conflicted Anger as a Central Dynamic in Depression in Adolescents—A Double Case Study
Authors: Henriksen Arne Kristian , Ulberg Randi , Tallberg Bjørn Peter Urban , Løvgren André , Johnsen Dahl Hanne-Sofie
Published: June 2021

The incidence of depression in teenagers has increased for many years and is one of the most common diagnosis in adolescent psychiatry. Effective and accessible psychotherapy methods need sustained attention since psychopharmaceutic treatment might be less effective in younger people than in adults. The First Experimental Study of Transference–In Teenagers (FEST-IT) is a Randomized Controlled Study (RCT) with a dismantling design. The main intention in this study was to illustrate a way to address parts of a case formulation by focusing a psychodynamic feature in two different therapies with a good outcome suffering from depression. We present two representative patients from the FEST-IT with case formulations revealing conflicted anger. The patients were different in many aspects, as were the therapeutic methods. Therapies with and without transference interpretations may help to understand what is helpful in therapy in general. It may also show how a more individualized approach can guide the therapy beyond diagnosis and to make it more effective for the specific patient. Looking into individual cases with good outcomes can help us address dynamic features in therapy and give some ideas about what works for whom. The use of nested qualitative double case studies may together add more knowledge about working aspects in successful therapies.
Exploration of Internal and External Factors of Swimmers’ Performance Based on Biofluid Mechanics and Computer Simulation
Authors: Liu Yifan , Lu Gang , Chen Junke , Zhu Qigang
Published: June 2021

The purpose of this study is to explore the influence of different swimming strokes on the performance of swimmers and the resistance of each part from the perspective of hydrodynamics. In this paper, the influence of internal and external factors on the swimming speed is analyzed comprehensively and meticulously from the macro and micro perspectives. In the macroscopic part, the swimming speed representation model is established, and the validity of the model is further verified by the analysis of experimental data and hydrodynamic equations. In the microscopic part, we carefully analyzed details such as the opening angle of the palm, the timing of the arm and leg and the angular velocity of each link of the human body. Combined with computer simulation, stereo modeling and numerical analysis are carried out, and the best scheme FOR how to cooperate with each part of the body in swimming is given.
Trajectories of Procedural and Interactional Justice as Predictors of Retirement among Swedish Workers: Differences between Three Groups of Retirees
Authors: Eib Constanze , Peristera Paraskevi , Bernhard-Oettel Claudia , Leineweber Constanze
Published: June 2021

Organizational justice is an important aspect of the psychosocial work environment, but there is a lack of studies on whether justice perceptions also predict retirement decisions. The aim of this study is to examine trajectories of procedural and interactional justice perceptions prior to retirement of three groups of retirees while considering self-rated health and important demographics. Data from the Swedish Longitudinal Occupational Survey of Health (2006–2018, N = 3000) were used. Respondents were grouped into early retirement, normative retirement and late retirement. Latent growth curve models and multinomial logistic regressions were conducted to test whether trajectories of justice perceptions prior to retirement differed between retirement groups while controlling for self-rated health development and demographic variables. Late retirees had higher intercept levels of interactional justice and higher intercept levels of self-rated health prior to retirement, compared to early retirees. Late retirees also showed a slower decrease in procedural justice compared to early retirees. Only intercept levels of self-rated health differed between early retirees and normative retirees, such that early retirees had lower levels of self-rated health prior to retirement. Keeping employees in the workforce is a major challenge for any aging society. Organizational justice perceptions in the years prior to retirement seem particularly influential for delaying retirement.
Psychological State after an Acute Coronary Syndrome: Impact of Physical Limitations
Authors: Serrano-Rosa Miguel-Ángel , León-Zarceño Eva , Giglio Cristina , Boix-Vilella Salvador , Moreno-Tenas Antonio , Pamies-Aubalat Lidia , Arrarte Vicente
Published: June 2021

The aim of this study was to investigate how physical limitations after ACS influence patients’ quality of life and health perception. This was a longitudinal clinical study. We recruited 146 patients diagnosed with ACS. The patients performed a stress test (Bruce’s protocol) for the evaluation of physical limitations and were classified according to the test result: without physical limitations (more than 10 METS), with some physical limitations (7 to 9 METS), and with high physical limitations (less than 6 METS). Significant differences were found between the three groups immediately after the diagnosis of ACS and after a period of three months, regarding health perception, anxiety, depression, sexual relationships, distress, and adjustment to disease. These differences resulted larger between the group with less limitations and the group with higher limitations. After 3 months, however, there was an overall improvement in all variables. In conclusion, physical limitations after ACS seem to influence perceived quality of life determined by measuring general health, vitality, total adaptation, emotional role, social adaptation, depression, and anxiety. Therefore, the highest the physical limitations, the poorer the psychological conditions and vice versa, even 3 months after ACS diagnosis.
Periodization and Programming for Individual 400 m Medley Swimmers
Authors: Hermosilla Francisco , González-Rave José M. , Del Castillo José Antonio , Pyne David B.
Published: June 2021

Knowledge in the scientific domain of individual medley (IM) swimming training over a competitive season is limited. The purpose of this study was to propose a detailed coaching framework incorporating the key elements of a periodized training regimen for a 400 m IM swimmer. This framework was based on the available coaching and scientific literature and the practical experience and expertise of the collaborating authors. The season has been divided in two or three macrocycles, further divided in three mesocycles each (six or nine mesocycles in total), in alignment with the two or three main competitions in each macrocycle. The principal training contents to develop during the season expressed in blood lactate zones are: aerobic training (~2 mmol·L−1), lactate threshold pace (~4 mmol·L−1) and VO2max (maximum oxygen uptake) (~6 mmol·L−1). Strength training should focus on maximum strength, power and speed endurance during the season. Altitude training camps can be placed strategically within the training season to promote physiological adaptation and improvements in performance. A well-constructed technical framework will permit development of training strategies for the 400 m IM swimmer to improve both training and competitive performance.
Development of a Questionnaire for Measuring Employees’ Perception of Selection, Optimisation and Compensation at the Leadership, Group and Individual Levels
Authors: Meng Annette , Karlsen Iben L. , Borg Vilhelm , Clausen Thomas
Published: June 2021

This study is the first to develop a questionnaire to measure employees’ perceptions of the use of the action strategies selection, optimisation, and compensation (SOC) beyond the individual level, which has so far been lacking in research and practice. The study thus contributes an important tool for research into the role of SOC strategies at the leadership, group, and individual levels for long and healthy working lives. It may also be used by practitioners as a tool to provide input when developing targeted interventions to support long and healthy working lives. The development of the questionnaire was based on SOC theory, qualitative and cognitive interviews, and existing SOC questionnaires. The validity and reliability of the questionnaire were tested on data from a cross-sectional survey with responses from 785 nurses and 244 dairy workers. Results from confirmatory factor analyses supported the theoretically expected nine-factor structure of the questionnaire in both study populations (nurses and dairy workers). Furthermore, the results largely supported the criterion validity and internal reliability of the scales in the questionnaire. Nevertheless, further validation across additional occupational groups is needed.
mTOR Signaling in the Inner Ear as Potential Target to Treat Hearing Loss
Authors: Cortada Maurizio , Levano Soledad , Bodmer Daniel
Published: June 2021

Hearing loss affects many people worldwide and occurs often as a result of age, ototoxic drugs and/or excessive noise exposure. With a growing number of elderly people, the number of people suffering from hearing loss will also increase in the future. Despite the high number of affected people, for most patients there is no curative therapy for hearing loss and hearing aids or cochlea implants remain the only option. Important treatment approaches for hearing loss include the development of regenerative therapies or the inhibition of cell death/promotion of cell survival pathways. The mammalian target of rapamycin (mTOR) pathway is a central regulator of cell growth, is involved in cell survival, and has been shown to be implicated in many age-related diseases. In the inner ear, mTOR signaling has also started to gain attention recently. In this review, we will emphasize recent discoveries of mTOR signaling in the inner ear and discuss implications for possible treatments for hearing restoration.
Electrochemical, Tribological and Biocompatible Performance of Electron Beam Modified and Coated Ti6Al4V Alloy
Authors: Nikolova Maria , Ormanova Maria , Nikolova Veselina , Apostolova Margarita D.
Published: June 2021

Vacuum cathodic arc TiN coatings with overlaying TiO2 film were deposited on polished and surface roughened by electron beam modification (EBM) Ti6Al4V alloy. The substrate microtopography consisted of long grooves formed by the liner scan of the electron beam with appropriate frequencies (500 (AR500) and 850 (AR850) Hz). EBM transformed the α + β Ti6Al4V mixed structure into a single α’-martensite phase. Тhe gradient TiN/TiO2 films deposited on mechanically polished (AR) and EBM (AR500 and AR850) alloys share the same surface chemistry and composition (almost stoichiometric TiN, anatase and rutile in different ratios) but exhibit different topographies (Sa equal to approximately 0.62, 1.73, and 1.08 μm, respectively) over areas of 50 × 50 μm. Although the nanohardness of the coatings on AR500 and AR850 alloy (approximately 10.45 and 9.02 GPa, respectively) was lower than that measured on the film deposited on AR alloy (about 13.05 GPa), the hybrid surface treatment offered improvement in critical adhesive loads, coefficient of friction, and wear-resistance of the surface. In phosphate buffer saline, all coated samples showed low corrosion potentials and passivation current densities, confirming their good corrosion protection. The coated EBM samples cultured with human osteoblast-like MG63 cells demonstrated increased cell attachment, viability, and bone mineralization activity especially for the AR500-coated alloy, compared to uncoated polished alloy. The results underline the synergetic effect between the sub-micron structure and composition of TiN/TiO2 coating and microarchitecture obtained by EBM.
Toxicological Profile of Plasmonic Nanoparticles in Zebrafish Model
Authors: d’Amora Marta , Raffa Vittoria , De Angelis Francesco , Tantussi Francesco
Published: June 2021

Plasmonic nanoparticles are increasingly employed in several fields, thanks to their unique, promising properties. In particular, these particles exhibit a surface plasmon resonance combined with outstanding absorption and scattering properties. They are also easy to synthesize and functionalize, making them ideal for nanotechnology applications. However, the physicochemical properties of these nanoparticles can make them potentially toxic, even if their bulk metallic forms are almost inert. In this review, we aim to provide a more comprehensive understanding of the potential adverse effects of plasmonic nanoparticles in zebrafish (Danio rerio) during both development and adulthood, focusing our attention on the most common materials used, i.e., gold and silver.
Endothelial Progenitor Cell-Derived Extracellular Vesicles: Potential Therapeutic Application in Tissue Repair and Regeneration
Authors: Terriaca Sonia , Fiorelli Elena , Scioli Maria Giovanna , Fabbri Giulia , Storti Gabriele , Cervelli Valerio , Orlandi Augusto
Published: June 2021

Recently, many studies investigated the role of a specific type of stem cell named the endothelial progenitor cell (EPC) in tissue regeneration and repair. EPCs represent a heterogeneous population of mononuclear cells resident in the adult bone marrow. EPCs can migrate and differentiate in injured sites or act in a paracrine way. Among the EPCs’ secretome, extracellular vesicles (EVs) gained relevance due to their possible use for cell-free biological therapy. They are more biocompatible, less immunogenic, and present a lower oncological risk compared to cell-based options. EVs can efficiently pass the pulmonary filter and deliver to target tissues different molecules, such as micro-RNA, growth factors, cytokines, chemokines, and non-coding RNAs. Their effects are often analogous to their cellular counterparts, and EPC-derived EVs have been tested in vitro and on animal models to treat several medical conditions, including ischemic stroke, myocardial infarction, diabetes, and acute kidney injury. EPC-derived EVs have also been studied for bone, brain, and lung regeneration and as carriers for drug delivery. This review will discuss the pre-clinical evidence regarding EPC-derived EVs in the different disease models and regenerative settings. Moreover, we will discuss the translation of their use into clinical practice and the possible limitations of this process.
Stratifying Cumulus Cell Samples Based on Molecular Profiling to Help Resolve Biomarker Discrepancies and to Predict Oocyte Developmental Competence
Authors: El-Maarri Osman , Jamil Muhammad Ahmer , Köster Maria , Nüsgen Nicole , Oldenburg Johannes , Montag Markus , van der Ven Hans , van der Ven Katrin
Published: June 2021

To increase the efficiency of assisted reproductive techniques (ART), molecular studies have been performed to identify the best predictive biomarkers for selecting the most suitable germ cells for fertilization and the best embryo for intra-uterine transfer. However, across different studies, no universal markers have been found. In this study, we addressed this issue by generating gene expression and CpG methylation profiles of outer cumulus cells obtained during intra-cytoplasmic sperm injection (ICSI). We also studied the association of the generated genomic data with the clinical parameters (spindle presence, zona pellucida birefringence, pronuclear pattern, estrogen level, endometrium size and lead follicle size) and the pregnancy result. Our data highlighted the presence of several parameters that affect analysis, such as inter-individual differences, inter-treatment differences, and, above all, specific treatment protocol differences. When comparing the pregnancy outcome following the long protocol (GnRH agonist) of ovarian stimulation, we identified the single gene markers (NME6 and ASAP1, FDR < 5%) which were also correlated with endometrium size, upstream regulators (e.g., EIF2AK3, FSH, ATF4, MKNK1, and TP53) and several bio-functions related to cell death (apoptosis) and cellular growth and proliferation. In conclusion, our study highlighted the need to stratify samples that are very heterogeneous and to use pathway analysis as a more reliable and universal method for identifying markers that can predict oocyte development potential.
(-)-Englerin-A Has Analgesic and Anti-Inflammatory Effects Independent of TRPC4 and 5
Authors: de Sousa Valente João , Alawi Khadija M , Bharde Sabah , Zarban Ali A. , Kodji Xenia , Thapa Dibesh , Argunhan Fulye , Barrett Brentton , Nagy Istvan , Brain Susan D.
Published: June 2021

Recently, we found that the deletion of TRPC5 leads to increased inflammation and pain-related behaviour in two animal models of arthritis. (-)-Englerin A (EA), an extract from the East African plant Phyllanthus engleri has been identified as a TRPC4/5 agonist. Here, we studied whether or not EA has any anti-inflammatory and analgesic properties via TRPC4/5 in the carrageenan model of inflammation. We found that EA treatment in CD1 mice inhibited thermal hyperalgesia and mechanical allodynia in a dose-dependent manner. Furthermore, EA significantly reduced the volume of carrageenan-induced paw oedema and the mass of the treated paws. Additionally, in dorsal root ganglion (DRG) neurons cultured from WT 129S1/SvIm mice, EA induced a dose-dependent cobalt uptake that was surprisingly preserved in cultured DRG neurons from 129S1/SvIm TRPC5 KO mice. Likewise, EA-induced anti-inflammatory and analgesic effects were preserved in the carrageenan model in animals lacking TRPC5 expression or in mice treated with TRPC4/5 antagonist ML204.This study demonstrates that while EA activates a sub-population of DRG neurons, it induces a novel TRPC4/5-independent analgesic and anti-inflammatory effect in vivo. Future studies are needed to elucidate the molecular and cellular mechanisms underlying EA’s anti-inflammatory and analgesic effects.
Toxicity and Antioxidant Activity of Fullerenol C60,70 with Low Number of Oxygen Substituents
Authors: Kovel Ekaterina S. , Kicheeva Arina G. , Vnukova Natalia G. , Churilov Grigory N. , Stepin Evsei A. , Kudryasheva Nadezhda S.
Published: June 2021

Fullerene is a nanosized carbon structure with potential drug delivery applications. We studied the bioeffects of a water-soluble fullerene derivative, fullerenol, with 10-12 oxygen groups (F10-12); its structure was characterized by IR and XPS spectroscopy. A bioluminescent enzyme system was used to study toxic and antioxidant effects of F10-12 at the enzymatic level. Antioxidant characteristics of F10-12 were revealed in model solutions of organic and inorganic oxidizers. Low-concentration activation of bioluminescence was validated statistically in oxidizer solutions. Toxic and antioxidant characteristics of F10-12 were compared to those of homologous fullerenols with a higher number of oxygen groups:F24-28 and F40-42. No simple dependency was found between the toxic/antioxidant characteristics and the number of oxygen groups on the fullerene’s carbon cage. Lower toxicity and higher antioxidant activity of F24-28 were identified and presumptively attributed to its higher solubility. An active role of reactive oxygen species (ROS) in the bioeffects of F10-12 was demonstrated. Correlations between toxic/antioxidant characteristics of F10-12 and ROS content were evaluated. Toxic and antioxidant effects were related to the decrease in ROS content in the enzyme solutions. Our results reveal a complexity of ROS effects in the enzymatic assay system.
Responsiveness to Hedgehog Pathway Inhibitors in T-Cell Acute Lymphoblastic Leukemia Cells Is Highly Dependent on 5′AMP-Activated Kinase Inactivation
Authors: Tosello Valeria , Bongiovanni Deborah , Di Martino Ludovica , Franchin Cinzia , Zanovello Paola , Arrigoni Giorgio , Piovan Erich
Published: June 2021

Numerous studies have shown that hedgehog inhibitors (iHHs) only partially block the growth of tumor cells, especially in vivo. Leukemia often expands in a nutrient-depleted environment (bone marrow and thymus). In order to identify putative signaling pathways implicated in the adaptive response to metabolically adverse conditions, we executed quantitative phospho-proteomics in T-cell acute lymphoblastic leukemia (T-ALL) cells subjected to nutrient-depleted conditions (serum starvation). We found important modulations of peptides phosphorylated by critical signaling pathways including casein kinase, mammalian target of rapamycin, and 5′AMP-activated kinase (AMPK). Surprisingly, in T-ALL cells, AMPK signaling was the most consistently downregulated pathway under serum-depleted conditions, and this coincided with increased GLI1 expression and sensitivity to iHHs, especially the GLI1/2 inhibitor GANT-61. Increased sensitivity to GANT-61 was also found following genetic inactivation of the catalytic subunit of AMPK (AMPKα1) or pharmacological inhibition of AMPK by Compound C. Additionally, patient-derived xenografts showing high GLI1 expression lacked activated AMPK, suggesting an important role for this signaling pathway in regulating GLI1 protein levels. Further, joint targeting of HH and AMPK signaling pathways in T-ALL cells by GANT-61 and Compound C significantly increased the therapeutic response. Our results suggest that metabolic adaptation that occurs under nutrient starvation in T-ALL cells increases responsiveness to HH pathway inhibitors through an AMPK-dependent mechanism and that joint therapeutic targeting of AMPK signaling and HH signaling could represent a valid therapeutic strategy in rapidly expanding tumors where nutrient availability becomes limiting.
Effects of Normal Synovial Fluid and Interferon Gamma on Chondrogenic Capability and Immunomodulatory Potential Respectively on Equine Mesenchymal Stem Cells
Authors: Zayed Mohammed , Adair Steve , Dhar Madhu
Published: June 2021

Synovial fluid contains cytokines, growth factors and resident mesenchymal stem cells (MSCs). The present study aimed to (1) determine the effects of autologous and allogeneic synovial fluid on viability, proliferation and chondrogenesis of equine bone marrow MSCs (BMMSCs) and (2) compare the immunomodulatory properties of equine synovial fluid MSCs (SFMSCs) and BMMSCs after stimulation with interferon gamma (INF-γ). To meet the first aim of the study, the proliferation and viability of MSCs were evaluated by MTS and calcein AM staining assays. To induce chondrogenesis, MSCs were cultured in a medium containing TGF-β1 or different concentrations of synovial fluid. To meet the second aim, SFMSCs and BMMSCs were stimulated with IFN-γ. The concentration of indoleamine-2,3-dioxygenase (IDO) and nitric oxide (NO) were examined. Our results show that MSCs cultured in autologous or allogeneic synovial fluid could maintain proliferation and viability activities. Synovial fluid affected chondrocyte differentiation significantly, as indicated by increased glycosaminoglycan contents, compared to the chondrogenic medium containing 5 ng/mL TGF-β1. After culturing with IFN-γ, the conditioned media of both BMMSCs and SFMSCs showed increased concentrations of IDO, but not NO. Stimulating MSCs with synovial fluid or IFN-γ could enhance chondrogenesis and anti-inflammatory activity, respectively, suggesting that the joint environment is suitable for chondrogenesis.
A Novel Method Facilitating the Simple and Low-Cost Preparation of Human Osteochondral Slice Explants for Large-Scale Native Tissue Analysis
Authors: Spinnen Jacob , Shopperly Lennard K. , Rendenbach Carsten , Kühl Anja A. , Sentürk Ufuk , Kendoff Daniel , Hemmati-Sadeghi Shabnam , Sittinger Michael , Dehne Tilo
Published: June 2021

For in vitro modeling of human joints, osteochondral explants represent an acceptable compromise between conventional cell culture and animal models. However, the scarcity of native human joint tissue poses a challenge for experiments requiring high numbers of samples and makes the method rather unsuitable for toxicity analyses and dosing studies. To scale their application, we developed a novel method that allows the preparation of up to 100 explant cultures from a single human sample with a simple setup. Explants were cultured for 21 days, stimulated with TNF-α or TGF-β3, and analyzed for cell viability, gene expression and histological changes. Tissue cell viability remained stable at >90% for three weeks. Proteoglycan levels and gene expression of COL2A1, ACAN and COMP were maintained for 14 days before decreasing. TNF-α and TGF-β3 caused dose-dependent changes in cartilage marker gene expression as early as 7 days. Histologically, cultures under TNF-α stimulation showed a 32% reduction in proteoglycans, detachment of collagen fibers and cell swelling after 7 days. In conclusion, thin osteochondral slice cultures behaved analogously to conventional punch explants despite cell stress exerted during fabrication. In pharmacological testing, both the shorter diffusion distance and the lack of need for serum in the culture suggest a positive effect on sensitivity. The ease of fabrication and the scalability of the sample number make this manufacturing method a promising platform for large-scale preclinical testing in joint research.
Plasma Gelsolin Reinforces the Diagnostic Value of FGF-21 and GDF-15 for Mitochondrial Disorders
Authors: Peñas Ana , Fernández-De la Torre Miguel , Laine-Menéndez Sara , Lora David , Illescas María , García-Bartolomé Alberto , Morales-Conejo Montserrat , Arenas Joaquín , Martín Miguel A. , Morán María , Domínguez-González Cristina , Ugalde Cristina
Published: June 2021

Mitochondrial disorders (MD) comprise a group of heterogeneous clinical disorders for which non-invasive diagnosis remains a challenge. Two protein biomarkers have so far emerged for MD detection, FGF-21 and GDF-15, but the identification of additional biomarkers capable of improving their diagnostic accuracy is highly relevant. Previous studies identified Gelsolin as a regulator of cell survival adaptations triggered by mitochondrial defects. Gelsolin presents a circulating plasma isoform (pGSN), whose altered levels could be a hallmark of mitochondrial dysfunction. Therefore, we investigated the diagnostic performance of pGSN for MD relative to FGF-21 and GDF-15. Using ELISA assays, we quantified plasma levels of pGSN, FGF-21, and GDF-15 in three age- and gender-matched adult cohorts: 60 genetically diagnosed MD patients, 56 healthy donors, and 41 patients with unrelated neuromuscular pathologies (non-MD). Clinical variables and biomarkers’ plasma levels were compared between groups. Discrimination ability was calculated using the area under the ROC curve (AUC). Optimal cut-offs and the following diagnostic parameters were determined: sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, and efficiency. Comprehensive statistical analyses revealed significant discrimination ability for the three biomarkers to classify between MD and healthy individuals, with the best diagnostic performance for the GDF-15/pGSN combination. pGSN and GDF-15 preferentially discriminated between MD and non-MD patients under 50 years, whereas FGF-21 best classified older subjects. Conclusion: pGSN improves the diagnosis accuracy for MD provided by FGF-21 and GDF-15.
Analysis of NHEJ-Based DNA Repair after CRISPR-Mediated DNA Cleavage
Authors: Song Beomjong , Yang Soyeon , Hwang Gue-Ho , Yu Jihyeon , Bae Sangsu
Published: June 2021

Genome editing using CRISPR-Cas9 nucleases is based on the repair of the DNA double-strand break (DSB). In eukaryotic cells, DSBs are rejoined through homology-directed repair (HDR), non-homologous end joining (NHEJ) or microhomology-mediated end joining (MMEJ) pathways. Among these, it is thought that the NHEJ pathway is dominant and occurs throughout a cell cycle. NHEJ-based DSB repair is known to be error-prone; however, there are few studies that delve into it deeply in endogenous genes. Here, we quantify the degree of NHEJ-based DSB repair accuracy (termed NHEJ accuracy) in human-originated cells by incorporating exogenous DNA oligonucleotides. Through an analysis of joined sequences between the exogenous DNA and the endogenous target after DSBs occur, we determined that the average value of NHEJ accuracy is approximately 75% in maximum in HEK 293T cells. In a deep analysis, we found that NHEJ accuracy is sequence-dependent and the value at the DSB end proximal to a protospacer adjacent motif (PAM) is relatively lower than that at the DSB end distal to the PAM. In addition, we observed a negative correlation between the insertion mutation ratio and the degree of NHEJ accuracy. Our findings would broaden the understanding of Cas9-mediated genome editing.
Revealing the Roles of Keratin 8/18-Associated Signaling Proteins Involved in the Development of Hepatocellular Carcinoma
Authors: Lim Younglan , Ku Nam-On
Published: June 2021

Although hepatocellular carcinoma (HCC) is developed with various etiologies, protection of hepatocytes seems basically essential to prevent the incidence of HCC. Keratin 8 and keratin 18 (K8/K18) are cytoskeletal intermediate filament proteins that are expressed in hepatocytes. They maintain the cell shape and protect cells under stress conditions. Their protective roles in liver damage have been described in studies of mouse models, and K8/K18 mutation frequency in liver patients. Interestingly, K8/K18 bind to signaling proteins such as transcription factors and protein kinases involved in HCC development. Since K8/K18 are abundant cytoskeletal proteins, K8/K18 binding with the signaling factors can alter the availability of the factors. Herein, we discuss the potential roles of K8/K18 in HCC development.
Role of Insulin in Health and Disease: An Update
Authors: Rahman Md Saidur , Hossain Khandkar Shaharina , Das Sharnali , Kundu Sushmita , Adegoke Elikanah Olusayo , Rahman Md. Ataur , Hannan Md. Abdul , Uddin Md Jamal , Pang Myung-Geol
Published: June 2021

Insulin is a polypeptide hormone mainly secreted by β cells in the islets of Langerhans of the pancreas. The hormone potentially coordinates with glucagon to modulate blood glucose levels; insulin acts via an anabolic pathway, while glucagon performs catabolic functions. Insulin regulates glucose levels in the bloodstream and induces glucose storage in the liver, muscles, and adipose tissue, resulting in overall weight gain. The modulation of a wide range of physiological processes by insulin makes its synthesis and levels critical in the onset and progression of several chronic diseases. Although clinical and basic research has made significant progress in understanding the role of insulin in several pathophysiological processes, many aspects of these functions have yet to be elucidated. This review provides an update on insulin secretion and regulation, and its physiological roles and functions in different organs and cells, and implications to overall health. We cast light on recent advances in insulin-signaling targeted therapies, the protective effects of insulin signaling activators against disease, and recommendations and directions for future research.
Using Zebrafish as a Disease Model to Study Fibrotic Disease
Authors: Wang Xixin , Copmans Daniëlle , de Witte Peter A. M.
Published: June 2021

In drug discovery, often animal models are used that mimic human diseases as closely as possible. These animal models can be used to address various scientific questions, such as testing and evaluation of new drugs, as well as understanding the pathogenesis of diseases. Currently, the most commonly used animal models in the field of fibrosis are rodents. Unfortunately, rodent models of fibrotic disease are costly and time-consuming to generate. In addition, present models are not very suitable for screening large compounds libraries. To overcome these limitations, there is a need for new in vivo models. Zebrafish has become an attractive animal model for preclinical studies. An expanding number of zebrafish models of human disease have been documented, for both acute and chronic diseases. A deeper understanding of the occurrence of fibrosis in zebrafish will contribute to the development of new and potentially improved animal models for drug discovery. These zebrafish models of fibrotic disease include, among others, cardiovascular disease models, liver disease models (categorized into Alcoholic Liver Diseases (ALD) and Non-Alcoholic Liver Disease (NALD)), and chronic pancreatitis models. In this review, we give a comprehensive overview of the usage of zebrafish models in fibrotic disease studies, highlighting their potential for high-throughput drug discovery and current technical challenges.
Hydrophobic Tagging-Mediated Degradation of Transcription Coactivator SRC-1
Authors: Choi So Ra , Wang Hee Myeong , Shin Min Hyeon , Lim Hyun-Suk
Published: June 2021

Steroid receptor coactivator-1 (SRC-1) is a transcription coactivator playing a pivotal role in mediating a wide range of signaling pathways by interacting with related transcription factors and nuclear receptors. Aberrantly elevated SRC-1 activity is associated with cancer metastasis and progression, and therefore, suppression of SRC-1 is emerging as a promising therapeutic strategy. In this study, we developed a novel SRC-1 degrader for targeted degradation of cellular SRC-1. This molecule consists of a selective ligand for SRC-1 and a bulky hydrophobic group. Since the hydrophobic moiety on the protein surface could mimic a partially denatured hydrophobic region of a protein, SRC-1 could be recognized as an unfolded protein and experience the chaperone-mediated degradation in the cells through the ubiquitin–proteasome system (UPS). Our results demonstrate that a hydrophobic-tagged chimeric molecule is shown to significantly reduce cellular levels of SRC-1 and suppress cancer cell migration and invasion. Together, these results highlight that our SRC-1 degrader represents a novel class of therapeutic candidates for targeting cancer metastasis. Moreover, we believe that the hydrophobic tagging strategy would be widely applicable to develop peptide-based protein degraders with enhanced cellular activity.
Critical Role of Hemopexin Mediated Cytoprotection in the Pathophysiology of Sickle Cell Disease
Authors: Ashouri Rani , Fangman Madison , Burris Alicia , Ezenwa Miriam O. , Wilkie Diana J. , Doré Sylvain
Published: June 2021

Circulating hemopexin is the primary protein responsible for the clearance of heme; therefore, it is a systemic combatant against deleterious inflammation and oxidative stress induced by the presence of free heme. This role of hemopexin is critical in hemolytic pathophysiology. In this review, we outline the current research regarding how the dynamic activity of hemopexin is implicated in sickle cell disease, which is characterized by a pathological aggregation of red blood cells and excessive hemolysis. This pathophysiology leads to symptoms such as acute kidney injury, vaso-occlusion, ischemic stroke, pain crises, and pulmonary hypertension exacerbated by the presence of free heme and hemoglobin. This review includes in vivo studies in mouse, rat, and guinea pig models of sickle cell disease, as well as studies in human samples. In summary, the current research indicates that hemopexin is likely protective against these symptoms and that rectifying depleted hemopexin in patients with sickle cell disease could improve or prevent the symptoms. The data compiled in this review suggest that further preclinical and clinical research should be conducted to uncover pathways of hemopexin in pathological states to evaluate its potential clinical function as both a biomarker and therapy for sickle cell disease and related hemoglobinopathies.
Insights into the Role of the Discontinuous TM7 Helix of Human Ferroportin through the Prism of the Asp325 Residue
Authors: Le Tertre Marlène , Elbahnsi Ahmad , Ka Chandran , Callebaut Isabelle , Le Gac Gérald
Published: June 2021

The negatively charged Asp325 residue has proved to be essential for iron export by human (HsFPN1) and primate Philippine tarsier (TsFpn) ferroportin, but its exact role during the iron transport cycle is still to be elucidated. It has been posited as being functionally equivalent to the metal ion-coordinating residue His261 in the C-lobe of the bacterial homolog BbFpn, but the two residues arise in different sequence motifs of the discontinuous TM7 transmembrane helix. Furthermore, BbFpn is not subject to extracellular regulation, contrary to its mammalian orthologues which are downregulated by hepcidin. To get further insight into the molecular mechanisms related to iron export in mammals in which Asp325 is involved, we investigated the behavior of the Asp325Ala, Asp325His, and Asp325Asn mutants in transiently transfected HEK293T cells, and performed a comparative structural analysis. Our biochemical studies clearly distinguished between the Asp325Ala and Asp325His mutants, which result in a dramatic decrease in plasma membrane expression of FPN1, and the Asp325Asn mutant, which alters iron egress without affecting protein localization. Analysis of the 3D structures of HsFPN1 and TsFpn in the outward-facing (OF) state indicated that Asp325 does not interact directly with metal ions but is involved in the modulation of Cys326 metal-binding capacity. Moreover, models of the architecture of mammalian proteins in the inward-facing (IF) state suggested that Asp325 may form an inter-lobe salt-bridge with Arg40 (TM1) when not interacting with Cys326. These findings allow to suggest that Asp325 may be important for fine-tuning iron recognition in the C-lobe, as well as for local structural changes during the IF-to-OF transition at the extracellular gate level. Inability to form a salt-bridge between TM1 and TM7b during iron translocation could lead to protein instability, as shown by the Asp325Ala and Asp325His mutants.
Critical Review of the Evolution of Extracellular Vesicles’ Knowledge: From 1946 to Today
Authors: Bazzan Erica , Tinè Mariaenrica , Casara Alvise , Biondini Davide , Semenzato Umberto , Cocconcelli Elisabetta , Balestro Elisabetta , Damin Marco , Radu Claudia Maria , Turato Graziella , Baraldo Simonetta , Simioni Paolo , Spagnolo Paolo , Saetta Marina , Cosio Manuel G.
Published: June 2021

Extracellular vesicles (EVs) are a family of particles/vesicles present in blood and body fluids, composed of phospholipid bilayers that carry a variety of molecules that can mediate cell communication, modulating crucial cell processes such as homeostasis, induction/dampening of inflammation, and promotion of repair. Their existence, initially suspected in 1946 and confirmed in 1967, spurred a sharp increase in the number of scientific publications. Paradoxically, the increasing interest for EV content and function progressively reduced the relevance for a precise nomenclature in classifying EVs, therefore leading to a confusing scientific production. The aim of this review was to analyze the evolution of the progress in the knowledge and definition of EVs over the years, with an overview of the methodologies used for the identification of the vesicles, their cell of origin, and the detection of their cargo. The MISEV 2018 guidelines for the proper recognition nomenclature and ways to study EVs are summarized. The review finishes with a “more questions than answers” chapter, in which some of the problems we still face to fully understand the EV function and potential as a diagnostic and therapeutic tool are analyzed.
Automated Classification of Fake News Spreaders to Break the Misinformation Chain
Authors: Leonardi Simone , Rizzo Giuseppe , Morisio Maurizio
Published: June 2021

In social media, users are spreading misinformation easily and without fact checking. In principle, they do not have a malicious intent, but their sharing leads to a socially dangerous diffusion mechanism. The motivations behind this behavior have been linked to a wide variety of social and personal outcomes, but these users are not easily identified. The existing solutions show how the analysis of linguistic signals in social media posts combined with the exploration of network topologies are effective in this field. These applications have some limitations such as focusing solely on the fake news shared and not understanding the typology of the user spreading them. In this paper, we propose a computational approach to extract features from the social media posts of these users to recognize who is a fake news spreader for a given topic. Thanks to the CoAID dataset, we start the analysis with 300 K users engaged on an online micro-blogging platform; then, we enriched the dataset by extending it to a collection of more than 1 M share actions and their associated posts on the platform. The proposed approach processes a batch of Twitter posts authored by users of the CoAID dataset and turns them into a high-dimensional matrix of features, which are then exploited by a deep neural network architecture based on transformers to perform user classification. We prove the effectiveness of our work by comparing the precision, recall, and f1 score of our model with different configurations and with a baseline classifier. We obtained an f1 score of 0.8076, obtaining an improvement from the state-of-the-art by 4%.