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1.
Immunity ; 38(4): 705-16, 2013 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-23499490

RESUMEN

La Crosse virus (LACV), a zoonotic Bunyavirus, is a major cause of pediatric viral encephalitis in the United States. A hallmark of neurological diseases caused by LACV and other encephalitic viruses is the induction of neuronal cell death. Innate immune responses have been implicated in neuronal damage, but no mechanism has been elucidated. By using in vitro studies in primary neurons and in vivo studies in mice, we have shown that LACV infection induced the RNA helicase, RIG-I, and mitochondrial antiviral signaling protein (MAVS) signaling pathway, resulting in upregulation of the sterile alpha and TIR-containing motif 1 (SARM1), an adaptor molecule that we found to be directly involved in neuronal damage. SARM1-mediated cell death was associated with induced oxidative stress response and mitochondrial damage. These studies provide an innate-immune signaling mechanism for virus-induced neuronal death and reveal potential targets for development of therapeutics to treat encephalitic viral infections.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis , Proteínas del Dominio Armadillo/metabolismo , Proteínas del Citoesqueleto/metabolismo , Encefalitis de California/inmunología , Virus La Crosse/inmunología , Mitocondrias/metabolismo , Neuronas/fisiología , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/inmunología , Animales , Proteínas del Dominio Armadillo/genética , Células Cultivadas , Proteínas del Citoesqueleto/genética , Encefalitis de California/complicaciones , Encefalitis de California/tratamiento farmacológico , Humanos , Inmunidad Innata , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Terapia Molecular Dirigida , Neuronas/virología , Estrés Oxidativo , Cultivo Primario de Células , Transducción de Señal/inmunología , Regulación hacia Arriba
2.
J Med Internet Res ; 22(10): e17049, 2020 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-33112238

RESUMEN

BACKGROUND: There is a disconnect between the ability to swiftly develop e-therapies for the treatment of depression, anxiety, and stress, and the scrupulous evaluation of their clinical utility. This creates a risk that the e-therapies routinely provided within publicly funded psychological health care have evaded appropriate rigorous evaluation in their development. OBJECTIVE: This study aims to conduct a meta-analytic review of the gold standard evidence of the acceptability and clinical effectiveness of e-therapies recommended for use in the National Health Service (NHS) in the United Kingdom. METHODS: Systematic searches identified appropriate randomized controlled trials (RCTs). Depression, anxiety, and stress outcomes at the end of treatment and follow-up were synthesized using a random-effects meta-analysis. The grading of recommendations assessment, development, and evaluation approach was used to assess the quality of each meta-analytic comparison. Moderators of treatment effect were examined using subgroup and meta-regression analysis. Dropout rates for e-therapies (as a proxy for acceptability) were compared against controls. RESULTS: A total of 24 studies evaluating 7 of 48 NHS-recommended e-therapies were qualitatively and quantitatively synthesized. Depression, anxiety, and stress outcomes for e-therapies were superior to controls (depression: standardized mean difference [SMD] 0.38, 95% CI 0.24 to 0.52, N=7075; anxiety and stress: SMD 0.43, 95% CI 0.24 to 0.63, n=4863), and these small effects were maintained at follow-up. Average dropout rates for e-therapies (31%, SD 17.35) were significantly higher than those of controls (17%, SD 13.31). Limited moderators of the treatment effect were found. CONCLUSIONS: Many NHS-recommended e-therapies have not been through an RCT-style evaluation. The e-therapies that have been appropriately evaluated generate small but significant, durable, beneficial treatment effects. TRIAL REGISTRATION: International Prospective Register of Systematic Reviews (PROSPERO) registration CRD42019130184; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=130184.


Asunto(s)
Ansiedad/terapia , Terapia Cognitivo-Conductual/métodos , Depresión/terapia , Intervención basada en la Internet/tendencias , Telemedicina/métodos , Femenino , Humanos , Masculino , Estudios Prospectivos , Resultado del Tratamiento
3.
J Med Internet Res ; 22(5): e16794, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32384055

RESUMEN

BACKGROUND: The usability and effectiveness of conversational agents (chatbots) that deliver psychological therapies is under-researched. OBJECTIVE: This study aimed to compare the system usability, acceptability, and effectiveness in older adults of 2 Web-based conversational agents that differ in theoretical orientation and approach. METHODS: In a randomized study, 112 older adults were allocated to 1 of the following 2 fully automated interventions: Manage Your Life Online (MYLO; ie, a chatbot that mimics a therapist using a method of levels approach) and ELIZA (a chatbot that mimics a therapist using a humanistic counseling approach). The primary outcome was problem distress and resolution, with secondary outcome measures of system usability and clinical outcome. RESULTS: MYLO participants spent significantly longer interacting with the conversational agent. Posthoc tests indicated that MYLO participants had significantly lower problem distress at follow-up. There were no differences between MYLO and ELIZA in terms of problem resolution. MYLO was rated as significantly more helpful and likely to be used again. System usability of both the conversational agents was associated with helpfulness of the agents and the willingness of the participants to reuse. Adherence was high. A total of 12% (7/59) of the MYLO group did not carry out their conversation with the chatbot. CONCLUSIONS: Controlled studies of chatbots need to be conducted in clinical populations across different age groups. The potential integration of chatbots into psychological care in routine services is discussed.


Asunto(s)
Internet/instrumentación , Solución de Problemas/fisiología , Anciano , Anciano de 80 o más Años , Comunicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos de Investigación
4.
Eur Respir J ; 52(5)2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30337447

RESUMEN

Residual pulmonary vascular obstruction (RPVO) and chronic thromboembolic pulmonary hypertension (CTEPH) are both long-term complications of acute pulmonary embolism, but it is unknown whether RPVO can be predicted by variants of fibrinogen associated with CTEPH.We used the Akaike information criterion to select the best predictive models for RPVO in two prospectively followed cohorts of acute pulmonary embolism patients, using as candidate variables the extent of the initial obstruction, clinical characteristics and fibrinogen-related data. We measured the selected models' goodness of fit by analysis of deviance and compared models using the Chi-squared test.RPVO occurred in 29 (28.4%) out of 102 subjects in the first cohort and 46 (25.3%) out of 182 subjects in the second. The best-fit predictive model derived in the first cohort (p=0.0002) and validated in the second cohort (p=0.0005) implicated fibrinogen Bß-chain monosialylation in the development of RPVO. When the derivation procedure excluded clinical characteristics, fibrinogen Bß-chain monosialylation remained a predictor of RPVO in the best-fit predictive model (p=0.00003). Excluding fibrinogen characteristics worsened the predictive model (p=0.03).Fibrinogen Bß-chain monosialylation, a common structural attribute of fibrin, helped predict RPVO after acute pulmonary embolism. Fibrin structure may contribute to the risk of developing RPVO.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico , Fibrinógeno/metabolismo , Arteria Pulmonar , Embolia Pulmonar/complicaciones , Adulto , Anciano , Arteriopatías Oclusivas/etiología , Femenino , Francia , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos
5.
J Virol ; 91(18)2017 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-28659480

RESUMEN

Mitochondria are crucial to proper neuronal function and overall brain health. Mitochondrial dysfunction within the brain has been observed in many neurodegenerative diseases, including prion disease. Several markers of decreased mitochondrial activity during prion infection have been reported, yet the bioenergetic respiratory status of mitochondria from prion-infected animals is unknown. Here we show that clinically ill transgenic mice overexpressing hamster prion protein (Tg7) infected with the hamster prion strain 263K suffer from a severe deficit in mitochondrial oxygen consumption in response to the respiratory complex II substrate succinate. Characterization of the mitochondrial proteome of purified brain mitochondria from infected and uninfected Tg7 mice showed significant differences in the relative abundance of key mitochondrial electron transport proteins in 263K-infected animals relative to that in controls. Our results suggest that at clinical stages of prion infection, dysregulation of respiratory chain proteins may lead to impairment of mitochondrial respiration in the brain.IMPORTANCE Mitochondrial dysfunction is present in most major neurodegenerative diseases, and some studies have suggested that mitochondrial processes may be altered during prion disease. Here we show that hamster prion-infected transgenic mice overexpressing the hamster prion protein (Tg7 mice) suffer from mitochondrial respiratory deficits. Tg7 mice infected with the 263K hamster prion strain have little or no signs of mitochondrial dysfunction at the disease midpoint but suffer from a severe deficit in mitochondrial respiration at the clinical phase of disease. A proteomic analysis of the isolated brain mitochondria from clinically affected animals showed that several proteins involved in electron transport, mitochondrial dynamics, and mitochondrial protein synthesis were dysregulated. These results suggest that mitochondrial dysfunction, possibly exacerbated by prion protein overexpression, occurs at late stages during 263K prion disease and that this dysfunction may be the result of dysregulation of mitochondrial proteins.


Asunto(s)
Encéfalo/patología , Respiración de la Célula , Mitocondrias/metabolismo , Enfermedades por Prión/patología , Animales , Modelos Animales de Enfermedad , Transporte de Electrón , Ratones Transgénicos , Mitocondrias/química , Oxígeno/metabolismo , Proteoma/análisis
6.
PLoS Pathog ; 12(2): e1005416, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26840342

RESUMEN

Sporadic Creutzfeldt-Jakob disease (sCJD) is the most prevalent of the human prion diseases, which are fatal and transmissible neurodegenerative diseases caused by the infectious prion protein (PrP(Sc)). The origin of sCJD is unknown, although the initiating event is thought to be the stochastic misfolding of endogenous prion protein (PrP(C)) into infectious PrP(Sc). By contrast, human growth hormone-associated cases of iatrogenic CJD (iCJD) in the United Kingdom (UK) are associated with exposure to an exogenous source of PrP(Sc). In both forms of CJD, heterozygosity at residue 129 for methionine (M) or valine (V) in the prion protein gene may affect disease phenotype, onset and progression. However, the relative contribution of each PrP(C) allotype to PrP(Sc) in heterozygous cases of CJD is unknown. Using mass spectrometry, we determined that the relative abundance of PrP(Sc) with M or V at residue 129 in brain specimens from MV cases of sCJD was highly variable. This result is consistent with PrP(C) containing an M or V at residue 129 having a similar propensity to misfold into PrP(Sc) thus causing sCJD. By contrast, PrP(Sc) with V at residue 129 predominated in the majority of the UK human growth hormone associated iCJD cases, consistent with exposure to infectious PrP(Sc) containing V at residue 129. In both types of CJD, the PrP(Sc) allotype ratio had no correlation with CJD type, age at clinical onset, or disease duration. Therefore, factors other than PrP(Sc) allotype abundance must influence the clinical progression and phenotype of heterozygous cases of CJD.


Asunto(s)
Síndrome de Creutzfeldt-Jakob/genética , Proteínas PrPC/genética , Proteínas PrPSc/genética , Adulto , Anciano , Encéfalo/patología , Química Encefálica , Síndrome de Creutzfeldt-Jakob/metabolismo , Síndrome de Creutzfeldt-Jakob/patología , Femenino , Humanos , Enfermedad Iatrogénica , Masculino , Metionina/genética , Persona de Mediana Edad , Fenotipo , Proteínas PrPC/química , Proteínas PrPC/metabolismo , Proteínas PrPSc/química , Proteínas PrPSc/metabolismo , Proteínas Recombinantes , Valina/genética
7.
Bioconjug Chem ; 29(6): 2074-2081, 2018 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-29763554

RESUMEN

The high specificity and favorable pharmacological properties of monoclonal antibodies (mAbs) have prompted significant interest in re-engineering this class of molecules to add novel functionalities for enhanced therapeutic and diagnostic potential. Here, we used the high affinity, meditope-Fab interaction to template and drive the rapid, efficient, and stable site-specific formation of a disulfide bond. We demonstrate that this template-catalyzed strategy provides a consistent and reproducible means to conjugate fluorescent dyes, cytotoxins, or "click" chemistry handles to meditope-enabled mAbs (memAbs) and memFabs. More importantly, we demonstrate this covalent functionalization is achievable using natural amino acids only, opening up the opportunity to genetically encode cysteine meditope "tags" to biologics. As proof of principle, genetically encoded, cysteine meditope tags were added to the N- and/or C-termini of fluorescent proteins, nanobodies, and affibodies, each expressed in bacteria, purified to homogeneity, and efficiently conjugated to different memAbs and meFabs. We further show that multiple T-cell and Her2-targeting bispecific molecules using this strategy potently activate T-cell signaling pathways in vitro. Finally, the resulting products are highly stable as evidenced by serum stability assays (>14 d at 37 °C) and in vivo imaging of tumor xenographs. Collectively, the platform offers the opportunity to build and exchange an array of functional moieties, including protein biologics, among any cysteine memAb or Fab to rapidly create, test, and optimize stable, multifunctional biologics.


Asunto(s)
Aminoácidos/química , Anticuerpos Monoclonales/química , Disulfuros/química , Inmunoconjugados/química , Animales , Neoplasias de la Mama/diagnóstico por imagen , Catálisis , Química Clic , Femenino , Colorantes Fluorescentes/química , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Células MCF-7 , Ratones , Modelos Moleculares , Imagen Óptica , Trastuzumab/química
8.
J Acoust Soc Am ; 141(3): EL307, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28372104

RESUMEN

Total removal of the larynx may be required to treat laryngeal cancer: speech is lost. This article shows that it may be possible to restore speech by sensing movement of the remaining speech articulators and use machine learning algorithms to derive a transformation to convert this sensor data into an acoustic signal. The resulting "silent speech," which may be delivered in real time, is intelligible and sounds natural. The identity of the speaker is recognisable. The sensing technique involves attaching small, unobtrusive magnets to the lips and tongue and monitoring changes in the magnetic field induced by their movement.


Asunto(s)
Acústica/instrumentación , Laringectomía , Laringe Artificial , Labio/fisiología , Aprendizaje Automático , Magnetismo/instrumentación , Imanes , Acústica del Lenguaje , Lengua/fisiología , Transductores , Calidad de la Voz , Fenómenos Biomecánicos , Humanos , Campos Magnéticos , Diseño de Prótesis , Recuperación de la Función , Procesamiento de Señales Asistido por Computador , Espectrografía del Sonido , Inteligibilidad del Habla , Factores de Tiempo
9.
J Proteome Res ; 15(12): 4518-4531, 2016 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-27597180

RESUMEN

Aggregated and protease-resistant mammalian prion protein (PrPSc) is the primary protein component of infectious prions. Enriched PrPSc preparations are often used to study the mechanisms that underly prion disease. However, most enrichment procedures are relatively nonspecific and tend to yield significant amounts of non-PrPSc components including various proteins that could confound functional and structural studies. It is thus important to identify these proteins and assess their potential relevance to prion pathogenesis. Following proteinase K treatment and phosphotungstic acid precipitation of brain homogenate, we have used mass spectrometry to analyze the protein content of PrPSc isolated from prion-infected mice, multiple cases of sporadic Creutzfeldt-Jakob disease (sCJD), and human growth hormone associated cases of iatrogenic CJD (iCJD). Creatine kinase was the primary protein contaminant in all PrPSc samples, while many of the other proteins identified were also found in non-CJD controls, which suggests that they are not CJD specific. Interestingly, the Alzheimer's disease associated peptide amyloid ß 1-42 (Aß1-42) was identified in the majority of the sCJD cases as well as non-CJD age-matched controls, while apoliprotein E was found in greater abundance in the sCJD cases. By contrast, while some of the iCJD cases showed evidence of higher molecular weight Aß oligomers, monomeric Aß1-42 peptide was not detected by immunoblot, and only one case had significant levels of apolipoprotein E. Our data are consistent with the age-associated deposition of Aß1-42 in older sporadic CJD and non-CJD patients and suggest that both apolipoprotein E and Aß1-42 abundance can differ depending upon the type of CJD.


Asunto(s)
Péptidos beta-Amiloides/análisis , Apolipoproteínas E/análisis , Síndrome de Creutzfeldt-Jakob/clasificación , Fragmentos de Péptidos/análisis , Proteínas Priónicas/análisis , Adulto , Factores de Edad , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Proteínas Priónicas/aislamiento & purificación
10.
Expert Rev Proteomics ; 12(2): 171-84, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25795148

RESUMEN

Prion diseases are a heterogeneous class of fatal neurodegenerative disorders associated with misfolding of host cellular prion protein (PrP(C)) into a pathological isoform, termed PrP(Sc). Prion diseases affect various mammals, including humans, and effective treatments are not available. Prion diseases are distinguished from other protein misfolding disorders - such as Alzheimer's or Parkinson's disease - in that they are infectious. Prion diseases occur sporadically without any known exposure to infected material, and hereditary cases resulting from rare mutations in the prion protein have also been documented. The mechanistic underpinnings of prion and other neurodegenerative disorders remain poorly understood. Various proteomics techniques have been instrumental in early PrP(Sc) detection, biomarker discovery, elucidation of PrP(Sc) structure and mapping of biochemical pathways affected by pathogenesis. Moving forward, proteomics approaches will likely become more integrated into the clinical and research settings for the rapid diagnosis and characterization of prion pathogenesis.


Asunto(s)
Enfermedades por Prión/metabolismo , Priones/química , Animales , Biomarcadores , Humanos , Enfermedades por Prión/diagnóstico , Priones/metabolismo , Proteómica/métodos
11.
Environ Manage ; 56(3): 765-76, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25900602

RESUMEN

This research examined the determinants of responsible hiking behavior through a lab-based experiment in which two managerial factors believed to influence individuals' behavior (the presentation of an educational message and the method of displaying degraded trail conditions) were varied across four experimental treatments in a 2 × 2 between subjects factorial design. The effect of trail degradation type (muddiness and erosion) and severity (moderate or severe) of trail degradation were also examined within each of the 4 treatment groups. Analyses revealed neither the educational message nor the method of displaying the image had a consistent and expected impact on individuals' behavioral intentions. In fact, participants who viewed the educational message were more likely to indicate they would hike off the trail. The effects of both trail degradation type and severity were consistent and significant with muddiness and more severe levels of degradation having a greater influence on individuals' intent to hike on the edge of or off the trail. The analyses also revealed both gender and hiking frequency had significant effects on behavioral intentions. Female participants were more likely to indicate they would turn around than males when they encountered degraded trail sections. Women were also less likely to indicate they would hike off the trail than men. Collectively, these findings highlight a variety of ways recreation resource managers can more efficiently inform recreationists about the impacts of off-trail hiking and prioritize trail management needs.


Asunto(s)
Conducta de Elección , Conservación de los Recursos Naturales , Difusión de la Información/métodos , Responsabilidad Social , Caminata/psicología , Femenino , Humanos , Liderazgo , Masculino
12.
J Proteome Res ; 13(11): 4620-34, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25140793

RESUMEN

Prion diseases are a heterogeneous group of neurodegenerative disorders affecting various mammals including humans. Prion diseases are characterized by a misfolding of the host-encoded prion protein (PrP(C)) into a pathological isoform termed PrP(Sc). In wild-type mice, PrP(C) is attached to the plasma membrane by a glycosylphosphatidylinositol (GPI) anchor and PrP(Sc) typically accumulates in diffuse nonamyloid deposits with gray matter spongiosis. By contrast, when mice lacking the GPI anchor are infected with the same prion inoculum, PrP(Sc) accumulates in dense perivascular amyloid plaques with little or no gray matter spongiosis. In order to evaluate whether different host biochemical pathways were implicated in these two phenotypically distinct prion disease models, we utilized a proteomics approach. In both models, infected mice displayed evidence of a neuroinflammatory response and complement activation. Proteins involved in cell death and calcium homeostasis were also identified in both phenotypes. However, mitochondrial pathways of apoptosis were implicated only in the nonamyloid form, whereas metal binding and synaptic vesicle transport were more disrupted in the amyloid phenotype. Thus, following infection with a single prion strain, PrP(C) anchoring to the plasma membrane correlated not only with the type of PrP(Sc) deposition but also with unique biochemical pathways associated with pathogenesis.


Asunto(s)
Amiloide/metabolismo , Fenotipo , Enfermedades por Prión/metabolismo , Enfermedades por Prión/fisiopatología , Proteómica/métodos , Animales , Apoptosis/genética , Apoptosis/fisiología , Western Blotting , Calcio/metabolismo , Membrana Celular/metabolismo , Cromatografía Liquida , Homeostasis/genética , Homeostasis/fisiología , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Espectrometría de Masas en Tándem
13.
J Biol Chem ; 288(32): 23331-47, 2013 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-23798682

RESUMEN

Neurofibrillary tangles, one of the hallmarks of Alzheimer disease (AD), are composed of paired helical filaments of abnormally hyperphosphorylated tau. The accumulation of these proteinaceous aggregates in AD correlates with synaptic loss and severity of dementia. Identifying the kinases involved in the pathological phosphorylation of tau may identify novel targets for AD. We used an unbiased approach to study the effect of 352 human kinases on their ability to phosphorylate tau at epitopes associated with AD. The kinases were overexpressed together with the longest form of human tau in human neuroblastoma cells. Levels of total and phosphorylated tau (epitopes Ser(P)-202, Thr(P)-231, Ser(P)-235, and Ser(P)-396/404) were measured in cell lysates using AlphaScreen assays. GSK3α, GSK3ß, and MAPK13 were found to be the most active tau kinases, phosphorylating tau at all four epitopes. We further dissected the effects of GSK3α and GSK3ß using pharmacological and genetic tools in hTau primary cortical neurons. Pathway analysis of the kinases identified in the screen suggested mechanisms for regulation of total tau levels and tau phosphorylation; for example, kinases that affect total tau levels do so by inhibition or activation of translation. A network fishing approach with the kinase hits identified other key molecules putatively involved in tau phosphorylation pathways, including the G-protein signaling through the Ras family of GTPases (MAPK family) pathway. The findings identify novel tau kinases and novel pathways that may be relevant for AD and other tauopathies.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Glucógeno Sintasa Quinasa 3/metabolismo , Proteína Quinasa 13 Activada por Mitógenos/metabolismo , Proteínas tau/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Animales , Línea Celular Tumoral , Corteza Cerebral/enzimología , Corteza Cerebral/patología , Epítopos/genética , Epítopos/metabolismo , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta , Humanos , Sistema de Señalización de MAP Quinasas/genética , Ratones , Ratones Transgénicos , Proteína Quinasa 13 Activada por Mitógenos/genética , Neuronas/enzimología , Neuronas/patología , Fosforilación , Proteínas tau/genética
14.
Front Robot AI ; 11: 1288818, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562409

RESUMEN

Along with the development of speech and language technologies, the market for speech-enabled human-robot interactions (HRI) has grown in recent years. However, it is found that people feel their conversational interactions with such robots are far from satisfactory. One of the reasons is the habitability gap, where the usability of a speech-enabled agent drops when its flexibility increases. For social robots, such flexibility is reflected in the diverse choice of robots' appearances, sounds and behaviours, which shape a robot's 'affordance'. Whilst designers or users have enjoyed the freedom of constructing a social robot by integrating off-the-shelf technologies, such freedom comes at a potential cost: the users' perceptions and satisfaction. Designing appropriate affordances is essential for the quality of HRI. It is hypothesised that a social robot with aligned affordances could create an appropriate perception of the robot and increase users' satisfaction when speaking with it. Given that previous studies of affordance alignment mainly focus on one interface's characteristics and face-voice match, we aim to deepen our understanding of affordance alignment with a robot's behaviours and use cases. In particular, we investigate how a robot's affordances affect users' perceptions in different types of use cases. For this purpose, we conducted an exploratory experiment that included three different affordance settings (adult-like, child-like, and robot-like) and three use cases (informative, emotional, and hybrid). Participants were invited to talk to social robots in person. A mixed-methods approach was employed for quantitative and qualitative analysis of 156 interaction samples. The results show that static affordance (face and voice) has a statistically significant effect on the perceived warmth of the first impression; use cases affect people's perceptions more on perceived competence and warmth before and after interactions. In addition, it shows the importance of aligning static affordance with behavioural affordance. General design principles of behavioural affordances are proposed. We anticipate that our empirical evidence will provide a clearer guideline for speech-enabled social robots' affordance design. It will be a starting point for more sophisticated design guidelines. For example, personalised affordance design for individual or group users in different contexts.

15.
Leukemia ; 38(6): 1236-1245, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38643304

RESUMEN

Targeting the metabolic dependencies of acute myeloid leukemia (AML) cells is a promising therapeutical strategy. In particular, the cysteine and methionine metabolism pathway (C/M) is significantly altered in AML cells compared to healthy blood cells. Moreover, methionine has been identified as one of the dominant amino acid dependencies of AML cells. Through RNA-seq, we found that the two nucleoside analogs 8-chloro-adenosine (8CA) and 8-amino-adenosine (8AA) significantly suppress the C/M pathway in AML cells, and methionine-adenosyltransferase-2A (MAT2A) is one of most significantly downregulated genes. Additionally, mass spectrometry analysis revealed that Venetoclax (VEN), a BCL-2 inhibitor recently approved by the FDA for AML treatment, significantly decreases the intracellular level of methionine in AML cells. Based on these findings, we hypothesized that combining 8CA or 8AA with VEN can efficiently target the Methionine-MAT2A-S-adenosyl-methionine (SAM) axis in AML. Our results demonstrate that VEN and 8CA/8AA synergistically decrease the SAM biosynthesis and effectively target AML cells both in vivo and in vitro. These findings suggest the promising potential of combining 8CA/8AA and VEN for AML treatment by inhibiting Methionine-MAT2A-SAM axis and provide a strong rationale for our recently activated clinical trial.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes , Sinergismo Farmacológico , Leucemia Mieloide Aguda , Metionina Adenosiltransferasa , Metionina , S-Adenosilmetionina , Sulfonamidas , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Humanos , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Sulfonamidas/farmacología , Metionina/metabolismo , Metionina/análogos & derivados , Metionina Adenosiltransferasa/metabolismo , Metionina Adenosiltransferasa/antagonistas & inhibidores , Metionina Adenosiltransferasa/genética , Animales , Ratones , S-Adenosilmetionina/farmacología , S-Adenosilmetionina/metabolismo , Adenosina/análogos & derivados , Adenosina/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral
16.
J Biol Chem ; 287(7): 4628-39, 2012 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-22179611

RESUMEN

Prion diseases or transmissible spongiform encephalopathy diseases are typically characterized by deposition of abnormally folded partially protease-resistant host-derived prion protein (PrPres), which is associated with activated glia and increased release of cytokines. This neuroinflammatory response may play a role in transmissible spongiform encephalopathy pathogenesis. We previously reported that brain homogenates from prion-infected mice induced cytokine protein release in primary astroglial and microglial cell cultures. Here we measured cytokine release by cultured glial cells to determine what factors in infected brain contributed to activation of microglia and astroglia. In assays analyzing IL-12p40 and CCL2 (MCP-1), glial cells were not stimulated in vitro by either PrPres purified from infected mouse brains or prion protein amyloid fibrils produced in vitro. However, significant glial stimulation was induced by clarified scrapie brain homogenates lacking PrPres. This stimulation was greatly reduced both by antibody to cyclophilin A (CyPA), a known mediator of inflammation in peripheral tissues, and by cyclosporine A, a CyPA inhibitor. In biochemical studies, purified truncated CyPA fragments stimulated a pattern of cytokine release by microglia and astroglia similar to that induced by scrapie-infected brain homogenates, whereas purified full-length CyPA was a poor stimulator. This requirement for CyPA truncation was not reported in previous studies of stimulation of peripheral macrophages, endothelial cell cardiomyocytes, and vascular smooth muscle cells. Therefore, truncated CyPA detected in brain following prion infection may have an important role in the activation of brain-derived primary astroglia and microglia in prion disease and perhaps other neurodegenerative or neuroinflammatory diseases.


Asunto(s)
Astrocitos/enzimología , Encéfalo/enzimología , Quimiocina CCL2/metabolismo , Ciclofilina A/metabolismo , Subunidad p40 de la Interleucina-12/metabolismo , Microglía/enzimología , Proteínas del Tejido Nervioso/metabolismo , Enfermedades por Prión/enzimología , Priones/metabolismo , Animales , Anticuerpos/farmacología , Astrocitos/patología , Ratones , Microglía/patología
17.
J Virol ; 86(21): 11763-78, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22915801

RESUMEN

Mammalian prions are thought to consist of misfolded aggregates (protease-resistant isoform of the prion protein [PrP(res)]) of the cellular prion protein (PrP(C)). Transmissible spongiform encephalopathy (TSE) can be induced in animals inoculated with recombinant PrP (rPrP) amyloid fibrils lacking mammalian posttranslational modifications, but this induction is inefficient in hamsters or transgenic mice overexpressing glycosylphosphatidylinositol (GPI)-anchored PrP(C). Here we show that TSE can be initiated by inoculation of misfolded rPrP into mice that express wild-type (wt) levels of PrP(C) and that synthetic prion strain propagation and selection can be affected by GPI anchoring of the host's PrP(C). To create prions de novo, we fibrillized mouse rPrP in the absence of molecular cofactors, generating fibrils with a PrP(res)-like protease-resistant banding profile. These fibrils induced the formation of PrP(res) deposits in transgenic mice coexpressing wt and GPI-anchorless PrP(C) (wt/GPI(-)) at a combined level comparable to that of PrP(C) expression in wt mice. Secondary passage into mice expressing wt, GPI(-), or wt plus GPI(-) PrP(C) induced TSE disease with novel clinical, histopathological, and biochemical phenotypes. Contrary to laboratory-adapted mouse scrapie strains, the synthetic prion agents exhibited a preference for conversion of GPI(-) PrP(C) and, in one case, caused disease only in GPI(-) mice. Our data show that novel TSE agents can be generated de novo solely from purified mouse rPrP after amplification in mice coexpressing normal levels of wt and anchorless PrP(C). These observations provide insight into the minimal elements required to create prions in vitro and suggest that the PrP(C) GPI anchor can modulate the propagation of synthetic TSE strains.


Asunto(s)
Priones/genética , Priones/aislamiento & purificación , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Priones/patogenicidad , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo
19.
J China Comput Assist Lang Learn ; 3(1): 208-230, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38013743

RESUMEN

Along with the development of speech and language technologies and growing market interest, social robots have attracted more academic and commercial attention in recent decades. Their multimodal embodiment offers a broad range of possibilities, which have gained importance in the education sector. It has also led to a new technology-based field of language education: robot-assisted language learning (RALL). RALL has developed rapidly in second language learning, especially driven by the need to compensate for the shortage of first-language tutors. There are many implementation cases and studies of social robots, from early government-led attempts in Japan and South Korea to increasing research interests in Europe and worldwide. Compared with RALL used for English as a foreign language (EFL), however, there are fewer studies on applying RALL for teaching Chinese as a foreign language (CFL). One potential reason is that RALL is not well-known in the CFL field. This scope review paper attempts to fill this gap by addressing the balance between classroom implementation and research frontiers of social robots. The review first introduces the technical tool used in RALL, namely the social robot, at a high level. It then presents a historical overview of the real-life implementation of social robots in language classrooms in East Asia and Europe. It then provides a summary of the evaluation of RALL from the perspectives of L2 learners, teachers and technology developers. The overall goal of this paper is to gain insights into RALL's potential and challenges and identify a rich set of open research questions for applying RALL to CFL. It is hoped that the review may inform interdisciplinary analysis and practice for scientific research and front-line teaching in future.

20.
Biochem Biophys Rep ; 34: 101446, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36923008

RESUMEN

Synucleinopathies are characterized by the deposition of alpha-synuclein (α-syn) aggregates in brain tissue. Pathological α-syn aggregates propagate in a prion-like manner and display prion-like biochemical properties. Using RT-QuIC, we measured α-syn seeding activity from brains of Dementia with Lewy body (DLB) patients post autoclave. Here, we show that autoclaving at 121 °C removes one to two log10 of α-syn seeding activity but the remaining 50% seeding dose (SD50) is more than 107/mg tissue. DLB brain samples autoclaved at 132 °C still revealed an SD50 of approximately 106/mg tissue. Our data suggest that DLB α-syn seeds are incompletely inactivated by standard autoclave, thus highlighting the need for evaluating laboratory procedures that fully inactivate them.

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