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Hyperreflexia associated with spasticity is a prevalent neurological condition characterized by excessive and exaggerated reflex responses to stimuli. Hyperreflexia can be caused by several diseases including multiple sclerosis, stroke and spinal cord injury (SCI). Although we have previously identified the contribution of the RAC1-PAK1 pathway underlying spinal hyperreflexia with SCI-induced spasticity, a feasible druggable target has not been validated. To assess the utility of targeting PAK1 to attenuate H-reflex hyperexcitability, we administered Romidepsin, a clinically available PAK1 inhibitor, in Thy1-YFP reporter mice. We performed longitudinal EMG studies with a study design that allowed us to assess pathological H-reflex changes and drug intervention effects over time, before and after contusive SCI. As expected, our results show a significant loss of rate-dependent depression - an indication of hyperreflexia and spasticity - 1 month following SCI as compared with baseline, uninjured controls (or before injury). Romidepsin treatment reduced signs of hyperreflexia in comparison with control cohorts and in pre- and post-drug intervention in SCI animals. Neuroanatomical study further confirmed drug response, as romidepsin treatment also reduced the presence of SCI-induced dendritic spine dysgenesis on α-motor neurons. Taken together, our findings extend previous work demonstrating the utility of targeting PAK1 activity in SCI-induced spasticity and support the novel use of romidepsin as an effective tool for managing spasticity. KEY POINTS: PAK1 plays a role in contributing to the development of spinal cord injury (SCI)-induced spasticity by contributing to dendritic spine dysgenesis. In this study, we explored the preclinical utility of inhibiting PAK1 to reduce spasticity and dendritic spine dysgenesis in an SCI mouse model. Romidepsin is a PAK1 inhibitor approved in the US in 2009 for the treatment of cutaneous T-cell lymphoma. Here we show that romidepsin treatment after SCI reduced SCI-induced H-reflex hyperexcitability and abnormal α-motor neuron spine morphology. This study provides compelling evidence that romidepsin may be a promising therapeutic approach for attenuating SCI-induced spasticity.
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Since iron overload is the commonest cause of morbidity and mortality in ß thalassemia major (ß-TM), it represents one major target in therapeutic management of the disease. The recently discovered erythroid regulator, erythroferrone (ERFE), governed by high levels of erythropoietin, was found to suppress hepcidin expression, thus increasing iron availability for developing erythroid progenitors. We aimed to investigate ERFE levels in Egyptian ß-TM patients as an attempt to understand its role in the prediction of iron overload states. Our study included 70 ß-TM patients, divided into two subgroups according to the degree of iron overload, and 30 sex and age-matched healthy subjects. ERFE gene expression was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR), and serum hepcidin was measured using enzyme-linked immunosorbent assay (ELISA) technique. Both ERFE gene expression levels and transferrin saturation (TS%) values were able to discriminate among cases with different degrees of iron overload, in contrast to hepcidin. TS% was acknowledged as the best predictor of iron overload (AUC 0.893) in comparison with serum hepcidin and ERFE gene levels (AUC 0.807 and 0.677, respectively), and ERFE gene expression was an independent predictor for the estimated TS%. In conclusion, we suggest that using the ERFE gene expression, combined with serum hepcidin estimation, can substantiate the role of estimated TS% as a promising tool in screening for iron overload in ß-TM patients.
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Regulação da Expressão Gênica , Sobrecarga de Ferro/sangue , Hormônios Peptídicos/sangue , Talassemia beta/sangue , Adolescente , Criança , Estudos Transversais , Egito , Feminino , Hepcidinas/sangue , Humanos , Ferro/sangue , Masculino , Reação em Cadeia da Polimerase em Tempo RealRESUMO
AIMS/HYPOTHESIS: The aim of this study was to determine the protective effects of human insulin and its analogues, B28Asp human insulin (insulin aspart) and B29Lys(ε-tetradecanoyl),desB30 human insulin (insulin detemir), against glucose-induced lifespan reduction and neuronal damage in the model organism Caenorhabditis elegans and to elucidate the underlying mechanisms. METHODS: Nematodes were cultivated under high glucose (HG) conditions comparable with the situation in diabetic patients and treated with human insulin and its analogues. Lifespan was assessed and neuronal damage was evaluated with regard to structural and functional impairment. Additionally, the activity of glyoxalase-1 and superoxide dismutase (SOD) and the formation of reactive oxygen species (ROS) and AGEs were determined. RESULTS: Insulin and its analogues reversed the life-shortening effect of HG conditions and prevented the glucose-induced neuronal impairment. Insulin treatment under HG conditions was associated with reduced concentration of glucose, as well as a reduced formation of ROS and AGEs, and increased SOD activity. These effects were dependent on the Forkhead box O (FOXO) homologue abnormal dauer formation (DAF)-16. Furthermore, glyoxalase-1 activity, which was impaired under HG conditions, was restored by human insulin. This was essential for the insulin-induced lifespan extension under HG conditions, as no change in lifespan was observed following either suppression or overexpression of glyoxalase-1. CONCLUSIONS/INTERPRETATION: Human insulin and its analogues prevent the reduction in lifespan and neuronal damage caused by HG conditions. The effect of human insulin is mediated by a daf-2/insulin receptor and daf-16/FOXO-dependent pathway and is mediated by upregulation of detoxifying mechanisms.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Insulina Regular Humana/farmacologia , Lactoilglutationa Liase/metabolismo , Animais , Dano ao DNA , Reparo do DNA , Regulação da Expressão Gênica no Desenvolvimento , Longevidade , Transdução de SinaisRESUMO
The COVID-19 global epidemic has compelled higher education institutions to reconsider their teaching methods. Because of this public health emergency, universities in higher education have adopted e-learning techniques as a solution to face-to-face education. Thus, e-learning has emerged as a critical technology in education at higher education institutions. Nonetheless, the effectiveness of e-learning systems is largely dependent on students' adoption of such systems. The study aims to evaluate the usefulness of task-technology fit (TTF) with the information system success model (ISSM) in perceiving students' adoption of e-learning with the goal of encouraging them to adopt e-learning in the context of higher education. The study employed a quantitative approach, and a theoretical model was evaluated with proposed hypotheses to find the relationships between the constructs. A questionnaire based on TTF and ISSM was distributed among the students, and 260 valid responses were received using a sample random sampling technique. Data was analyzed with the help of SPSS and Partial Least Squares-Structural Equation Modeling (PLS-SEM). After analyzing the data, it was found that perceived ease of use, perceived usefulness, system use, and task technology fit of e-learning are positively and significantly influenced by system quality, information quality, perceived enjoyment, technology characteristics, and task characteristics. The results of TTF and ISSM on system use show a positive effect on e-learning benefits in educational institutions, with all male and female students completely satisfied with the use of e-learning systems. As a result, we advise students to use e-learning systems for educational purposes and should have motivated them to do so through lecturers at higher-level educational institutions.
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Higher education has given the flipped classroom a lot of attention as a result of its pedagogical success. As a result of the adoption of social media, smartphones, and computers in the classroom, new strategies for providing online courses, such as flipped classrooms, have evolved. To further understand the effects of such technology integration in teaching, the study looked at the responses of 213 undergraduate students at King Faisal University. For a semester, participants took their regular classes in a flipped classroom. The participants answered a survey made expressly for this study to find out if they would still be willing to use flipped classes following this experience. A structural equation modeling approach was used to analyze the research paradigm, which is based on the technological adoption model. The findings demonstrated that each variable category had a favorable influence on perceived usefulness and perceived ease of use. Perceived utility and ease of use serve as mediating elements in the relationship between independent variables and attitudes toward adopting flipped classrooms. Additionally, the findings indicated that ATFC and BIFC have a positive influence on the acceptance of flipped classrooms. In terms of education and learning, the utilization of classroom instruction is positively impacted by both ATFC and BIFC. These findings show that attitudes toward blended learning and intentions to use flipped classrooms have the biggest impacts on the adoption of the concept in Saudi Arabia higher education.
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Communication, carer-health care professional relationship, and power dynamics are important considerations in pediatric health care. There is paucity of evidence about best practice for addressing parents of children in a hospital care setting, potentially affecting health care provision. We surveyed parents attending Evelina London Children's Hospital to assess the preferences of parents to different appellations used by health care professionals to address them and their impact on parents' perception of involvement in the care of their child. Two hundred fifty-four (84.6%) parents responded to the survey. Two hundred one (92.6%) parents did not feel the way they were addressed contributed to them feeling their value was neglected from the care of their child. At the center studied, appellations most acceptable to parents were their first name or "Mum"/"Dad." In current practice, the appellation used most is "Mum"/"Dad," 112 (69.1%) and 40 (62%), respectively.
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Hospitalização/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Hospitalização/tendências , Humanos , Londres , Masculino , Pediatria/métodos , Pediatria/tendências , Relações Profissional-Família , Inquéritos e QuestionáriosRESUMO
Patient reported outcome measures (PROMs) are essential to fully understand the impact of diseases and the effectiveness of treatment from a patient's perspective. Generic and disease-specific tools have been used to assess the impact of nephrolithiasis on patients' quality of life (QoL), as well as the impact of various treatment modalities. Additionally, various studies have investigated the factors that might determine the impact of the disease on the patients' QoL. Here were view the available knowledge on this nascent topic and highlight the need for extensive future research in this crucial area.
Las mediciones de los resultados informados por los pacientes (PROMs) son esenciales para entender completamente el impacto de las enfermedades y la efectividad de los tratamientos desde la perspectiva del paciente. Se han utilizado herramientas genéricas y específicas de la enfermedad para evaluar el impacto de la nefrolitiasis en la calidad de vida de los pacientes (QoL) y también el impacto de varias modalidades de tratamiento. Además, varios estudios han investigado los factores que pueden determinar el impacto de la enfermedad sobre la QoL de los pacientes. Aquí revisamos el conocimiento disponible sobre este tema emergente y subrayamos la necesidad de una futura eintensa investigación en esta crucial área.
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Cálculos Renais , Qualidade de Vida , Humanos , Cálculos Renais/terapiaRESUMO
To evade immunity, many viruses express interferon antagonists that target STAT transcription factors as a major component of pathogenesis. Because of a lack of direct structural data, these interfaces are poorly understood. We report the structural analysis of full-length STAT1 binding to an interferon antagonist of a human pathogenic virus. The interface revealed by transferred cross-saturation NMR is complex, involving multiple regions in both the viral and cellular proteins. Molecular mapping analysis, combined with biophysical characterization and in vitro/in vivo functional assays, indicates that the interface is significant in disease caused by a pathogenic field-strain lyssavirus, with critical roles for contacts between the STAT1 coiled-coil/DNA-binding domains and specific regions within the viral protein. These data elucidate the potentially complex nature of IFN antagonist/STAT interactions, and the spatial relationship of protein interfaces that mediate immune evasion and replication, providing insight into how viruses can regulate these essential functions via single multifunctional proteins.
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Imunidade Inata , Lyssavirus , Fator de Transcrição STAT1 , Animais , Células COS , Chlorocebus aethiops , Feminino , Células HEK293 , Humanos , Lyssavirus/química , Lyssavirus/imunologia , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Ressonância Magnética Nuclear Biomolecular , Domínios Proteicos , Fator de Transcrição STAT1/química , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/imunologiaRESUMO
Deletions in mitochondrial DNA (mtDNA) accumulate during aging. Expression of the Caenorhabditis elegans apurinic/apyrimidinic endonuclease 1 (APE1) ortholog exo-3, involved in DNA repair, is reduced by 45% (P < 0.05) during aging of C. elegans. Suppression of exo-3 by treatment with RNAi resulted in a threefold increase in mtDNA deletions (P < 0.05), twofold enhanced generation of reactive oxygen species (ROS) (P < 0.01), distortion of the structural integrity of the nervous system, reduction of head motility by 43% (P < 0.01) and whole animal motility by 38% (P < 0.05). Suppression of exo-3 significantly reduced life span: mean life span decreased from 18.5 +/- 0.4 to 15.4 +/- 0.1 days (P < 0.001) and maximum life span from 25.9 +/- 0.4 to 23.2 +/- 0.1 days (P = 0.001). Additional treatment of exo-3-suppressed animals with a mitochondrial uncoupler decreased ROS levels, reduced neuronal damage, and increased motility and life span. Additional suppression of the C. elegans p53 ortholog cep-1 in exo-3 RNAi-treated animals similarly decreased ROS levels, preserved neuronal integrity, and increased motility and life span. In wild-type animals, suppression of cep-1, involved in downregulation of exo-3, increased expression of exo-3 without a significant effect on ROS levels, preserved neuronal integrity, and increased motility and life span. Suppression of the C. elegans thioredoxin orthologs trx-1 and trx-2, involved in the redox chaperone activity of exo-3, overrides the protective effect of cep-1 RNAi treatment on neuronal integrity, neuronal function, mean and maximum life span. These results show that APE1/EXO-3, p53/CEP-1, and thioredoxin affect each other and that these interactions determine aging as well as neuronal structure and function.
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Envelhecimento , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Tiorredoxinas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , DNA Mitocondrial/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Deleção de Genes , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/genética , Proteína Supressora de Tumor p53/genéticaAssuntos
Criopreservação , Destinação do Embrião , Embrião de Mamíferos , Fertilização in vitro , Atitude , Regulamentação Governamental , Instalações de Saúde , Humanos , Consentimento Livre e Esclarecido , Política , Política Pública , Padrões de Referência , Religião , Controle Social Formal , Reino Unido , Valor da VidaAssuntos
Aborto Eugênico , Gravidez Múltipla , Gravidez , Gestantes , Gêmeos , Apoio Financeiro , Humanos , Jurisprudência , Motivação , Médicos , Política , Pobreza , Reino UnidoAssuntos
Aborto Induzido , Política Pública , Estupro , Violência , Mulheres , Argélia , Feminino , Humanos , Islamismo , PolíticaRESUMO
OBJECTIVE: Establishing Caenorhabditis elegans as a model for glucose toxicity-mediated life span reduction. RESEARCH DESIGN AND METHODS: C. elegans were maintained to achieve glucose concentrations resembling the hyperglycemic conditions in diabetic patients. The effects of high glucose on life span, glyoxalase-1 activity, advanced glycation end products (AGEs), and reactive oxygen species (ROS) formation and on mitochondrial function were studied. RESULTS: High glucose conditions reduced mean life span from 18.5 + or - 0.4 to 16.5 + or - 0.6 days and maximum life span from 25.9 + or - 0.4 to 23.2 + or - 0.4 days, independent of glucose effects on cuticle or bacterial metabolization of glucose. The formation of methylglyoxal-modified mitochondrial proteins and ROS was significantly increased by high glucose conditions and reduced by mitochondrial uncoupling and complex IIIQo inhibition. Overexpression of the methylglyoxal-detoxifying enzyme glyoxalase-1 attenuated the life-shortening effect of glucose by reducing AGE accumulation (by 65%) and ROS formation (by 50%) and restored mean (16.5 + or - 0.6 to 20.6 + or - 0.4 days) and maximum life span (23.2 + or - 0.4 to 27.7 + or - 2.3 days). In contrast, inhibition of glyoxalase-1 by RNAi further reduced mean (16.5 + or - 0.6 to 13.9 + or - 0.7 days) and maximum life span (23.2 + or - 0.4 to 20.3 + or - 1.1 days). The life span reduction by glyoxalase-1 inhibition was independent from the insulin signaling pathway because high glucose conditions also affected daf-2 knockdown animals in a similar manner. CONCLUSIONS: C. elegans is a suitable model organism to study glucose toxicity, in which high glucose conditions limit the life span by increasing ROS formation and AGE modification of mitochondrial proteins in a daf-2 independent manner. Most importantly, glucose toxicity can be prevented by improving glyoxalase-1-dependent methylglyoxal detoxification or preventing mitochondrial dysfunction.
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Caenorhabditis elegans/metabolismo , Glucose/toxicidade , Hiperglicemia/metabolismo , Longevidade/fisiologia , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/ultraestrutura , Modelos Animais de Doenças , Humanos , Expectativa de Vida/tendências , Microscopia Eletrônica de Varredura , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Studies of mutations affecting lifespan in Caenorhabditis elegans show that mitochondrial generation of reactive oxygen species (ROS) plays a major causative role in organismal aging. Here, we describe a novel mechanism for regulating mitochondrial ROS production and lifespan in C. elegans: progressive mitochondrial protein modification by the glycolysis-derived dicarbonyl metabolite methylglyoxal (MG). We demonstrate that the activity of glyoxalase-1, an enzyme detoxifying MG, is markedly reduced with age despite unchanged levels of glyoxalase-1 mRNA. The decrease in enzymatic activity promotes accumulation of MG-derived adducts and oxidative stress markers, which cause further inhibition of glyoxalase-1 expression. Over-expression of the C. elegans glyoxalase-1 orthologue CeGly decreases MG modifications of mitochondrial proteins and mitochondrial ROS production, and prolongs C. elegans lifespan. In contrast, knock-down of CeGly increases MG modifications of mitochondrial proteins and mitochondrial ROS production, and decreases C. elegans lifespan.