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Mutations in the human INF2 gene cause autosomal dominant focal segmental glomerulosclerosis (FSGS)-a condition characterized by podocyte loss, scarring, and subsequent kidney degeneration. To understand INF2-linked pathogenicity, we examined the effect of pathogenic INF2 on renal epithelial cell lines and human primary podocytes. Our study revealed an increased incidence of mitotic cells with surplus microtubule-organizing centers fostering multipolar spindle assembly, leading to nuclear abnormalities, particularly multi-micronucleation. The levels of expression of exogenous pathogenic INF2 were similar to those of endogenous INF2. The aberrant nuclear phenotypes were observed regardless of the expression method used (retrovirus infection or plasmid transfection) or the promoter (LTR or CMV) used, and were absent with exogenous wild type INF2 expression. This indicates that the effect of pathogenic INF2 is not due to overexpression or experimental cell manipulation, but instead to the intrinsic properties of pathogenic INF2. Inactivation of the INF2 catalytic domain prevented aberrant nuclei formation. Pathogenic INF2 triggered the translocation of the transcriptional cofactor MRTF into the nucleus. RNA sequencing revealed a profound alteration in the transcriptome that could be primarily attributed to the sustained activation of the MRTF-SRF transcriptional complex. Cells eventually underwent mitotic catastrophe and death. Reducing MRTF-SRF activation mitigated multi-micronucleation, reducing the extent of cell death. Our results, if validated in animal models, could provide insights into the mechanism driving glomerular degeneration in INF2-linked FSGS and may suggest potential therapeutic strategies for impeding FSGS progression.
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Forminas , Mitose , Podócitos , Transcriptoma , Humanos , Mitose/genética , Podócitos/metabolismo , Podócitos/patologia , Transcriptoma/genética , Forminas/genética , Forminas/metabolismo , Morte Celular/genética , Glomerulosclerose Segmentar e Focal/genética , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/patologia , Nefropatias/genética , Nefropatias/patologia , Nefropatias/metabolismo , Mutação , Núcleo Celular/metabolismo , Núcleo Celular/genética , Linhagem CelularRESUMO
Using a prototype approach to emotion concepts, we mapped the internal structure and content of the everyday concept of envy (as used in the United States) and its translation equivalents of envidia in Spanish and Neid in German. In Study 1 (total N = 415), the features of the concept of envy, envidia, and Neid were generated via an open-ended questionnaire. In Study 2 (total N = 404), participants rated the degree of typicality of the constitutive features on a forced-choice questionnaire. The prototype analysis of envy, supplemented with network analyses, revealed that the largest connected set of features of envy, envidia, and Neid shared a group of central features, including features related to success or to people with a better appearance. Still, envy, envidia, and Neid did differ with respect to their constituent peripheral features as well as the density of their networks, their structure, and the betweenness centrality of the nodes. These results suggest that a prototype approach combined with network analysis is a convenient approach for studying the internal structure of everyday emotion concepts and the degree of overlap with respect to the translation equivalents in different countries.
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Comparação Transcultural , Humanos , Alemanha , Espanha , Feminino , Masculino , Adulto , Estados Unidos , Adulto Jovem , Ciúme , Pessoa de Meia-Idade , Emoções/fisiologia , Adolescente , Inquéritos e QuestionáriosRESUMO
INTRODUCTION: The drug provocation test (DPT) is the gold standard for the drug allergy workup; however, it is not free from severe adverse reactions. Our aim was to obtain robust data that predict a reaction during or after the DPT at the first contact with the patient in the allergy outpatient clinic. METHODS: The population of this cross-sectional study comprised all patients undergoing a drug allergy workup (clinical assessment, specific IgE, or skin tests, or DPT) at University Hospital Fundacion Alcorcon in 2016. DPTs were performed until therapeutic doses were reached, and late reactions were checked. The clinical disorders assessed in our study were classified mainly as absence of allergic reactions, morbilliform rash, urticaria, anaphylaxis, and other cutaneous disorders. RESULTS: Physicians from the Allergy Unit programmed drug allergy workups in 977 patients (median age, 52 years; women, 64.54%). DPTs were not performed for 165 drugs involved in the reactions. Patients who did not undergo DPT were older than patients who did (positive or negative) (p = 0.0001). Positive DPT results were detected in 6.00% of DPTs performed, and most were for amoxicillin and metamizole (15-25% each). Multinomial logistic regression showed that positive reactions were more probable after DPT if the same clinical disorder was diagnosed at the first visit, including the episodes not considered allergic episodes (OR = 0.2, <0.01), except for anaphylaxis, which favored not performing DPTs (OR = 11, p < 0.001). CONCLUSION: We conclude that clinical practice in the diagnosis of drug allergy in our Allergy Department is safe, without over-diagnosis.
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Anafilaxia , Hipersensibilidade a Drogas , Humanos , Feminino , Pessoa de Meia-Idade , Antibacterianos/efeitos adversos , Anafilaxia/diagnóstico , Anafilaxia/epidemiologia , Anafilaxia/induzido quimicamente , Estudos Transversais , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/epidemiologia , Testes Cutâneos/métodos , HospitaisRESUMO
Cow's milk allergy can result in anaphylactic reactions. The estimated prevalence of cow's milk allergy in developed countries ranges from 0.5% to 3% at age 1 year. Our objective was to perform a systematic review and, if possible, a meta-analysis to assess the frequency of fatal and recurrent anaphylaxis induced by cow's milk. We searched PubMed/MEDLINE, EMBASE, and the Web of Science for studies that had assessed fatal and recurrent anaphylaxis induced by cow's milk for the population of a country or at least an administrative region. Our review included cohort, cross-sectional, and registry studies that had assessed the incidence or prevalence of recurrent anaphylaxis or the incidence of fatal anaphylaxis due to cow's milk. The pooled prevalence of recurrence (PR) for at least an episode of anaphylaxis was 26.98% (3.85-189.1). Teymourpour et al (Iran) reported the highest PR (53.10%); the two studies with the lowest PR were from France (5.2 and 0.42, respectively) (p < .01). Nine studies on fatal anaphylaxis were selected (41 deaths) and found to be highly heterogeneous (I2 = 75.9%). Levy et al and Bassagio et al reported the highest incidence rate (IR 0.15 and 0.6 deaths per million persons-year). The PR of anaphylaxis was approximately one quarter of patients with anaphylaxis due to cow's milk, while deaths from anaphylaxis caused by cow's milk were very rare, although some studies report rates as high as 15 times the lowest IR.
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Anafilaxia , Hipersensibilidade a Leite , Humanos , Animais , Leite/efeitos adversos , Anafilaxia/epidemiologia , Anafilaxia/etiologia , Estudos Transversais , AlérgenosRESUMO
Coherence quantifies the statistical fluctuations in an optical field and has been extensively studied in the space, time, and polarization degrees of freedom. In the context of space, coherence theory has been formulated between two transverse positions as well as between two azimuthal positions, referred to as transverse spatial coherence and angular coherence, respectively. In this paper, we formulate the theory of coherence for optical fields in the radial degree of freedom and discuss the associated concepts of coherence radial width, radial quasi-homogeneity, and radial stationarity with some physically realizable examples of radially partially coherent fields. Furthermore, we propose an interferometric scheme for measuring radial coherence.
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Proteolipids are proteins with unusual lipid-like properties. It has long been established that PLP and plasmolipin, which are two unrelated membrane-tetra-spanning myelin proteolipids, can be converted in vitro into a water-soluble form with a distinct conformation, raising the question of whether these, or other similar proteolipids, can adopt two different conformations in the cell to adapt their structure to distinct environments. Here, we show that MALL, another proteolipid with a membrane-tetra-spanning structure, distributes in membranes outside the nucleus and, within the nucleus, in membrane-less, liquid-like PML body biomolecular condensates. Detection of MALL in one or other environment was strictly dependent on the method of cell fixation used, suggesting that MALL adopts different conformations depending on its physical environment -lipidic or aqueous- in the cell. The acquisition of the condensate-compatible conformation requires PML expression. Excess MALL perturbed the distribution of the inner nuclear membrane proteins emerin and LAP2ß, and that of the DNA-binding protein BAF, leading to the formation of aberrant nuclei. This effect, which is consistent with studies identifying overexpressed MALL as an unfavorable prognostic factor in cancer, could contribute to cell malignancy. Our study establishes a link between proteolipids, membranes and biomolecular condensates, with potential biomedical implications.
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Condensados Biomoleculares , Neoplasias , Núcleo Celular , Humanos , Conformação Molecular , Proteolipídeos/químicaRESUMO
Apical localization of Intercellular Adhesion Receptor (ICAM)-1 regulates the adhesion and guidance of leukocytes across polarized epithelial barriers. Here, we investigate the molecular mechanisms that determine ICAM-1 localization into apical membrane domains of polarized hepatic epithelial cells, and their effect on lymphocyte-hepatic epithelial cell interaction. We had previously shown that segregation of ICAM-1 into apical membrane domains, which form bile canaliculi and bile ducts in hepatic epithelial cells, requires basolateral-to-apical transcytosis. Searching for protein machinery potentially involved in ICAM-1 polarization we found that the SNARE-associated protein plasmolipin (PLLP) is expressed in the subapical compartment of hepatic epithelial cells in vitro and in vivo. BioID analysis of ICAM-1 revealed proximal interaction between this adhesion receptor and PLLP. ICAM-1 colocalized and interacted with PLLP during the transcytosis of the receptor. PLLP gene editing and silencing increased the basolateral localization and reduced the apical confinement of ICAM-1 without affecting apicobasal polarity of hepatic epithelial cells, indicating that ICAM-1 transcytosis is specifically impaired in the absence of PLLP. Importantly, PLLP depletion was sufficient to increase T-cell adhesion to hepatic epithelial cells. Such an increase depended on the epithelial cell polarity and ICAM-1 expression, showing that the epithelial transcytotic machinery regulates the adhesion of lymphocytes to polarized epithelial cells. Our findings strongly suggest that the polarized intracellular transport of adhesion receptors constitutes a new regulatory layer of the epithelial inflammatory response.
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Adesão Celular/fisiologia , Células Epiteliais/metabolismo , Hepatócitos/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/metabolismo , Linfócitos T/metabolismo , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Fígado/metabolismo , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/genética , Transcitose/fisiologiaRESUMO
In INF2-a formin linked to inherited renal and neurological disease in humans-the DID is preceded by a short N-terminal extension of unknown structure and function. INF2 activation is achieved by Ca2+-dependent association of calmodulin (CaM). Here, we show that the N-terminal extension of INF2 is organized into two α-helices, the first of which is necessary to maintain the perinuclear F-actin ring and normal cytosolic F-actin content. Biochemical assays indicated that this helix interacts directly with CaM and contains the sole CaM-binding site (CaMBS) detected in INF2. The residues W11, L14 and L18 of INF2, arranged as a 1-4-8 motif, were identified as the most important residues for the binding, W11 being the most critical of the three. This motif is conserved in vertebrate INF2 and in the human population. NMR and biochemical analyses revealed that CaM interacts directly through its C-terminal lobe with the INF2 CaMBS. Unlike control cells, INF2 KO cells lacked the perinuclear F-actin ring, had little cytosolic F-actin content, did not respond to increased Ca2+ concentrations by making more F-actin, and maintained the transcriptional cofactor MRTF predominantly in the cytoplasm. Whereas expression of intact INF2 restored all these defects, INF2 with inactivated CaMBS did not. Our study reveals the structure of the N-terminal extension, its interaction with Ca2+/CaM, and its function in INF2 activation.
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Actinas , Proteínas dos Microfilamentos , Humanos , Forminas , Actinas/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Citoesqueleto de Actina/metabolismo , Ligação ProteicaRESUMO
Polarization singularities and topological polarization structures are generic features of inhomogeneous vector wave fields of any nature. However, their experimental studies mostly remain restricted to optical waves. Here, we report the observation of polarization singularities, topological Möbius-strip structures, and skyrmionic textures in 3D polarization fields of inhomogeneous sound waves. Our experiments are made in the ultrasonic domain using nonparaxial propagating fields generated by space-variant 2D acoustic sources. We also retrieve distributions of the 3D spin density in these fields. Our results open the avenue to investigations and applications of topological features and nontrivial 3D vector properties of structured sound waves.
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The primary cilium is a specialized plasma membrane protrusion with important receptors for signalling pathways. In polarized epithelial cells, the primary cilium assembles after the midbody remnant (MBR) encounters the centrosome at the apical surface. The membrane surrounding the MBR, namely remnant-associated membrane patch (RAMP), once situated next to the centrosome, releases some of its lipid components to form a centrosome-associated membrane patch (CAMP) from which the ciliary membrane stems. The RAMP undergoes a spatiotemporal membrane refinement during the formation of the CAMP, which becomes highly enriched in condensed membranes with low lateral mobility. To better understand this process, we have developed a correlative imaging approach that yields quantitative information about the lipid lateral packing, its mobility and collective assembly at the plasma membrane at different spatial scales over time. Our work paves the way towards a quantitative understanding of the spatiotemporal lipid collective assembly at the plasma membrane as a functional determinant in cell biology and its direct correlation with the membrane physicochemical state. These findings allowed us to gain a deeper insight into the mechanisms behind the biogenesis of the ciliary membrane of polarized epithelial cells.
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Membrana Celular , Células Epiteliais , LipídeosRESUMO
We study the conditions under which fluorescent beads can be used to emulate single fluorescent molecules in the calibration of optical microscopes. Although beads are widely used due to their brightness and easy manipulation, there can be notable differences between the point spread functions (PSFs) they produce and those for single-molecule fluorophores, caused by their different emission patterns and sizes. We study theoretically these differences for various scenarios, e.g., with or without polarization channel splitting, to determine the conditions under which the use of beads as a model for single molecules is valid. We also propose methods to model the blurring due to the size difference and compensate for it to produce PSFs that are more similar to those for single molecules.
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Corantes Fluorescentes , CalibragemRESUMO
Formins are a conserved family of proteins that primarily act to form linear polymers of actin. Despite their importance to the normal functioning of the cytoskeleton, for a long time, the only two formin genes known to be a genetic cause of human disorders were DIAPH1 and DIAPH3, whose mutation causes two distinct forms of hereditary deafness. In the last 10 years, however, the formin INF2 has emerged as an important target of mutations responsible for the appearance of focal segmental glomerulosclerosis, which are histological lesions associated with glomerulus degeneration that often leads to end-stage renal disease. In some rare cases, focal segmental glomerulosclerosis concurs with Charcot-Marie-Tooth disease, which is a degenerative neurological disorder affecting peripheral nerves. All known INF2 gene mutations causing disease map to the exons encoding the amino-terminal domain. In this review, we summarize the structure, biochemical features and functions of INF2, conduct a systematic and comprehensive analysis of the pathogenic INF2 mutations, including a detailed study exon-by-exon of patient cases and mutations, address the impact of the pathogenic mutations on the structure, regulation and known functions of INF2, draw a series of conclusions that could be useful for INF2-related disease diagnosis, and suggest lines of research for future work on the molecular mechanisms by which INF2 causes disease.
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Forminas/genética , Éxons/genética , Glomerulosclerose Segmentar e Focal/genética , Humanos , Mutação/genética , Doenças Neurodegenerativas/genéticaRESUMO
OBJECTIVE: We assessed the prevalence of bullying and cyberbullying in 12-16-year-olds and the association with student self-reports after a police informative talk. DESIGN: We used a survey to assess the impact of the intervention: 1458 high school students received a police informative talk during the 2018-2019 school year and completed the self-administered EBIP-Q and ECI-Q questionnaires. Perceptions of conduct and bystanders' attitudes were assessed. Correspondence indexes were calculated using Cohen's kappa and gender differences studied using logistic regression. RESULTS: 81.34% (95% CI: 79.33-83.34) of students were involved in bullying and 54.75% (95% CI: 52.19-56.76) in cyberbullying. Almost 90% of participants did not perceive their real bullying correctly. Girls were more frequently victims of bullying and cyberbullying (OR = 1.67 and OR = 1.22, p = .004), but more frequently self-reported being bullies or victim/bully (OR = 0.57 and 0.39, p < .05). Male bystanders reported 7.33% (p < .001) more feelings of inadequacy than girls when witnessing bullying. CONCLUSION: Poor self-reporting reflects poor understanding of bullying and cyber-bullying. Police information sessions might produce the opposite reactions in adolescents, as they reduce bullying to visible, harmful violence. Educators should focus on adolescent relationships rather than violence prevention. A friendly, male-targeted approach is needed.
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Bullying , Vítimas de Crime , Adolescente , Feminino , Humanos , Masculino , Polícia , Prevalência , Autorrelato , Inquéritos e QuestionáriosRESUMO
Mid-spatial frequency (MSF) structures on optical surfaces degrade system performance and a perturbation model is typically used to simplify the assessment of their effects. In this simple model, MSF phase structures are dragged along the nominal rays of a system to yield estimates of wavefronts in the exit pupil that may be used for further analysis. However, the validity of the perturbation model remains an open area of study. We extend our previous assessment of the validity of this model [K. Liang, Opt. Express 27, 3390-3408 (2019)] that was focused on the analysis of single-frequency MSF structures in two dimensions to now include error estimates for broad-spectra MSF structures in three dimensions.
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Geometric phases are a universal concept that underpins numerous phenomena involving multi-component wave fields. These polarization-dependent phases are inherent in interference effects, spin-orbit interaction phenomena, and topological properties of vector wave fields. Geometric phases have been thoroughly studied in two-component fields, such as two-level quantum systems or paraxial optical waves. However, their description for fields with three or more components, such as generic nonparaxial optical fields routinely used in modern nano-optics, constitutes a nontrivial problem. Here we describe geometric, dynamical, and total phases calculated along a closed spatial contour in a multi-component complex field, with particular emphasis on 2D (paraxial) and 3D (nonparaxial) optical fields. We present several equivalent approaches: (i) an algebraic formalism, universal for any multi-component field; (ii) a dynamical approach using the Coriolis coupling between the spin angular momentum and reference-frame rotations; and (iii) a geometric representation, which unifies the Pancharatnam-Berry phase for the 2D polarization on the Poincaré sphere and the Majorana-sphere representation for the 3D polarized fields. Most importantly, we reveal close connections between geometric phases, angular-momentum properties of the field, and topological properties of polarization singularities in 2D and 3D fields, such as C-points and polarization Möbius strips.
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BACKGROUND: Reports of fatal anaphylaxis remain scarce because of the rarity of the condition and the fact that information is limited to a few countries. OBJECTIVE: Our objective was to investigate clinical and demographic characteristics and the causes of fatal anaphylaxis in Spain using two databases of cases of fatal anaphylaxis. METHODS: We analysed fatal anaphylaxis in a series from the Spanish hospital system and a series from the National Institute of Toxicology and Forensic Sciences (Instituto Nacional de Toxicología y Ciencias Forenses [INTCF]), which predominantly comprise extrahospital deaths. Deaths from the Spanish hospital system were retrieved from among all deaths occurring during 1998-2011 using codes related to anaphylaxis. Deaths due to anaphylaxis in the INTCF database during the same period were retrieved by 2 allergists, who identified cases in which anaphylaxis was a possible cause of death. A logistic regression model was constructed to predict the characteristics of fatal anaphylaxis in each database. RESULTS: The incidence of death by anaphylaxis in Spain using both databases was 0.25 (95% CI, 0.24-0.26) deaths per million person-years. The most frequent causes of death in the hospital system were drugs (46.1%), unknown causes (40.0%), and foods (10.4%); in the INTCF, the most common causes of death were drugs (47.2%), insect stings (30.6%), and foods (11.1%). The logistic regression model showed that fatal anaphylaxis due to unknown causes (OR 15.2, 95% CI 1.8-129.8) was more likely in the hospital database, whereas insect stings (OR 100, 95% CI 10-833.3) and previous atopic comorbidity (OR 15.2, 95% CI 6.3-33.3) were more likely in the INTCF database. CONCLUSIONS & CLINICAL RELEVANCE: The estimated frequency of fatal anaphylaxis in Spain was among the lowest reported. Future studies of fatal anaphylaxis should use databases from different origins in order to show the considerable heterogeneity in this type of death.
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Anafilaxia/etiologia , Anafilaxia/mortalidade , Bases de Dados Factuais , Adulto , Feminino , Medicina Legal , Humanos , Masculino , Espanha/epidemiologiaRESUMO
In diamond-machined freeform manufacturing processes, a tool-tip often leaves behind characteristic mid-spatial frequency (MSF) structures on the optical surface. Unwanted movement between the tool-tip and the part results in MSF structures with random variations. Here, we analyze the effects of these MSF structures on the system's optical performance and derive simple analytic estimates for the optical transfer function in terms of the parameters of these structures. These expressions are expected to aid in MSF tolerancing.
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Star test polarimetry is an imaging polarimetry technique in which an element with spatially-varying birefringence is placed in the pupil plane to encode polarization information into the point-spread function (PSF) of an imaging system. In this work, a variational calculation is performed to find the optimal birefringence distribution that effectively encodes polarization information while producing the smallest possible PSF, thus maximizing the resolution for imaging polarimetry. This optimal solution is found to be nearly equivalent to the birefringence distribution that results from a glass window being subjected to three uniformly spaced stress points at its edges, which has been used in previous star test polarimetry setups.
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Assessment of the performance degradation caused by the mid-spatial frequency (MSF) structure on optical surfaces often relies on a perturbation method that dovetails with the familiar sequence of models based on geometrical and physical optics. In the case of imaging systems, the perturbative step yields estimates of wavefronts in the exit pupil which are, in turn, used to extract performance measures such as MTF, PSF, and Strehl ratio. To date, the validity of that perturbation appears to be poorly understood. We present methods to estimate the errors of this approach and thereby arrive at a rule of thumb for its accuracy: the error is approximately equal to the RMS of the MSF structure at its source multiplied by the square of the ratio between a particular Fresnel zone size and a characteristic length of the MSF structure.
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In many applications it is natural to seek to extract a characteristic scale for a function's variations by reference to a frequency spectrum. Although the moments of a spectrum appear to promise simple options to make such a connection, standard Fourier methods fail to yield finite moments when the function's domain is itself finite. We investigate a family of Fourier-like bases with rapidly decaying spectra that yield well-defined moments for such cases. These bases are derived by considering classes of functions for which a normalised mean square derivative is stationary. They are shown to provide precisely the type of spectrum needed to complete a recent investigation of mid-spatial frequency structure on optical surfaces [K. Liang, Opt. Express 27, 3390-3408 (2019)].