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Introducción: La calidad de vida relacionada con la salud (CVRS) y los estados de ánimo son indicadores cruciales del bienestar en adolescentes, pero su relación con estudiantes de Antioquia, Colombia, no ha sido ampliamente estudiada. Objetivo: Determinar la CVRS y los estados de ánimo en escolares de Antioquia-Colombia. Materiales y métodos: Estudio transversal con 1957 escolares de 9 a 20 años. Se aplicaron mediciones de CVRS, ansiedad, depresión, hostilidad y alegría, actividad física, comportamiento sedentario, apoyo social de padres y nivel socioeconómico. Resultados: La calidad de vida alta (CVA) es más elevada en hombres, personas con alegría, estudiantes con apoyo de padres, activos físicamente y personas de nivel socioeconómico alto y medio. AL aumentar un año de edad, disminuye en un 15 % la CVA, y al aumentar la depresión, la ansiedad y el comportamiento sedentario disminuye la CVA. Además, los niveles de depresión y ansiedad son mayores en mujeres, estudiantes mayores, sin apoyo de los padres y personas sedentarias. Conclusiones: La CVRS se asocia con estados de ánimo, actividad física, comportamiento sedentario y apoyo de los padres; mientras que los estados de ánimo se asocian con el sexo, el apoyo de los padres, la CVS y el sedentarismo.
Introduction: Even though health-related quality of life (HRQL) and mood states are key indicators of the well-being of adolescents, their relationship has not been analyzed in students from Antioquia, Colombia. Objective: To determine HRQL and mood states in schoolchildren from Antioquia. Materials and methods: A cross-sectional study was conducted on 1,957 schoolchildren and adolescents aged between 9 and 20 years. Measurements of HRQL, anxiety, depression, hostility and happiness, physical activity, sedentary behavior, parental social support, and socioeconomic status were applied. Results: A high quality of life (HQL) was observed more frequently in male participants, students with parental support, physically active, and those belonging to medium and high socioeconomic status. HQL decreased 15% as their age increased by one year. Also, HQL was reduced when depression, anxiety, and sedentary behavior increased. Furthermore, depression and anxiety levels were higher in women, older students, as well as in those without parental control and with sedentary behavior. Conclusions: HRQL is associated with mood states, physical activity, sedentary behavior, and parental support. In contrast, mood states are related to gender, parental support, HQL, and sedentary lifestyle.
Introdução: A qualidade de vida relacionada à saúde (CVRS) e os estados de humor são indicadores cruciais de bem-estar em adolescentes, mas sua relação com estudantes de Antioquia, Colômbia, não foi amplamente estudada. Objetivo: Determinar a CVRS e os estados de humor em escolares de Antioquia-Colômbia. Materiais e métodos: Estudo transversal com 1.957 escolares de 9 a 20 anos. Foram aplicadas medidas de QVRS, ansiedade, depressão, hostilidade e felicidade, atividade física, comportamento sedentário, apoio social dos pais e nível socioeconômico. Resultados: A alta qualidade de vida (CVA) é maior em homens, pessoas com alegria, estudantes com apoio parental, fisicamente ativos e pessoas de nível socioeconômico alto e médio. À medida que a idade aumenta em um ano, diminui em 15% o CVA, e ao aumentar a depressão, a ansiedade e o comportamento sedentário aumentam, o CVA diminui. Além disso, os níveis de depressão e ansiedade são mais elevados nas mulheres, nos estudantes mais velhos, sem apoio dos pais e nas pessoas sedentárias. Conclusões: A QVRS está associada a estados de humor, atividade física, comportamento sedentário e apoio parental; enquanto os estados de humor estão associados ao sexo, apoio parental, CVS e estilo de vida sedentário.
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Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Saúde , Emoções , Felicidade , HostilidadeRESUMO
OBJECTIVES: To describe the availability and barriers to access post-stroke rehabilitation services in Latin America. MATERIALS AND METHODS: We conducted a multi-national survey in Latin American countries. The survey consisted of three sections: (1) the national state of post-stroke rehabilitation; (2) the local state of post-stroke rehabilitation; and (3) the coverage and financing of post-stroke services. Stroke leaders from the surveyed countries were involved in developing and disseminating the survey. RESULTS: 261 responses were collected from 17 countries. The mean age of respondents was 42.4 ± 10.1 years, and 139 (54.5 %) of the respondents were male. National clinical guidelines for post-stroke rehabilitation were reported by 67 (25.7 %) of the respondents. However, there were discrepancies between respondents within the same country. Stroke units, physiotherapy, occupational therapy, speech therapy, and neuropsychological therapy services were less common in public than private settings. The main barriers for inpatient and outpatient services included limited rehabilitation facilities, coverage, and rehabilitation personnel. The main source of financing for the inpatient and outpatient services was the national health insurance, followed by out-of-pocket payments. Private and out-of-pocket costs were more frequently reported in outpatient services. CONCLUSIONS: Post-stroke rehabilitation services in Latin American countries are restricted due to a lack of coverage by the public health system and private insurers, human resources, and financial aid. Public settings offer fewer post-stroke rehabilitation services compared to private settings. Developing consensus guidelines, increasing coverage, and using innovative approaches to deliver post-stroke rehabilitation is paramount to increase access without posing a financial burden.
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Selenium, zinc, copper, and manganese are essential components of antioxidant enzymes involved in the elimination of reactive oxygen species (ROS). Given that cancer cells produce high levels of ROS and the accumulation of ROS can lead to cell death, cancer cells may be susceptible to strategies that reduce ROS elimination. In this work, we prepared several artificial diets that contained normal carbohydrate, protein, and lipid levels but lacked selenium, zinc, copper, or manganese. The anticancer activity of these diets was examined in a metastatic ovarian cancer model, established by injecting ID8 Trp53-/- murine ovarian cancer cells into the peritoneal cavity of C57BL/6JRj mice. Treatments started 15 days later and consisted of replacing a normal diet with one of the artificial diets for several weeks. A significant improvement in mice survival was observed when the normal diet was replaced with the selenium-free diet. Diets lacking zinc, copper, or manganese showed no significant impact on mice survival. All diets were very well tolerated. The anticancer efficacy of a diet lacking selenium was confirmed in mice with metastatic colon cancer and in mice with metastatic triple-negative breast cancer. These results suggest that diets lacking selenium hold potential for the treatment of metastatic cancers.
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Cobre , Dieta , Manganês , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas , Selênio , Zinco , Animais , Feminino , Selênio/farmacologia , Selênio/administração & dosagem , Manganês/administração & dosagem , Zinco/farmacologia , Camundongos , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/dietoterapia , Neoplasias do Colo/patologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/dietoterapia , Linhagem Celular Tumoral , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Metástase Neoplásica , Espécies Reativas de Oxigênio/metabolismo , HumanosRESUMO
Numerous natural antioxidants commonly found in our daily diet have demonstrated significant benefits for human health and various diseases by counteracting the impact of reactive oxygen and nitrogen species. Their chemical properties enable a range of biological actions, including antihypertensive, antimicrobial, anti-inflammatory, anti-fibrotic, and anticancer effects. Despite promising outcomes from preclinical studies, ongoing debate persists regarding their reproducibility in human clinical models. This controversy largely stems from a lack of understanding of the pharmacokinetic properties of these compounds, coupled with the predominant focus on monotherapies in research, neglecting potential synergistic effects arising from combining different antioxidants. This study aims to provide an updated overview of natural antioxidants, operating under the hypothesis that a multitherapeutic approach surpasses monotherapy in efficacy. Additionally, this study underscores the importance of integrating these antioxidants into the daily diet, as they have the potential to prevent the onset and progression of various diseases. To reinforce this perspective, clinical findings pertaining to the treatment and prevention of non-alcoholic fatty liver disease and conditions associated with ischemia and reperfusion phenomena, including myocardial infarction, postoperative atrial fibrillation, and stroke, are presented as key references.
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Our study aimed to verify the possibilities of effectively applying chronnectomics methods to reconstruct the dynamic processes of network transition between three types of brain states, namely, eyes-closed rest, eyes-open rest, and a task state. The study involved dense EEG recordings and reconstruction of the source-level time-courses of the signals. Functional connectivity was measured using the phase lag index, and dynamic analyses concerned coupling strength and variability in alpha and beta frequencies. The results showed significant and dynamically specific transitions regarding processes of eyes opening and closing and during the eyes-closed-to-task transition in the alpha band. These observations considered a global dimension, default mode network, and central executive network. The decrease of connectivity strength and variability that accompanied eye-opening was a faster process than the synchronization increase during eye-opening, suggesting that these two transitions exhibit different reorganization times. While referring the obtained results to network studies, it was indicated that the scope of potential similarities and differences between rest and task-related networks depends on whether the resting state was recorded in eyes closed or open condition.
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Encéfalo , Eletroencefalografia , Humanos , Masculino , Feminino , Adulto , Encéfalo/fisiologia , Adulto Jovem , Rede Nervosa/fisiologia , Descanso/fisiologiaRESUMO
OBJECTIVE: Estrogen receptor-positive (ER+) breast cancer represents about 80% of cases, tamoxifen is the election neoadjuvant chemotherapy. However, a large percentage of patients develop chemoresistance, compromising recovery. Clinical evidence suggests that high plasmatic levels of low-density lipoproteins (LDL) could promote cancer progression. The present study analyzed the effect of LDL on the primary plasmatic active Tamoxifen's metabolites resistance acquisition, 4-hydroxytamoxifen (4OH-Tam) and 4-hydroxy-N-desmethyl-tamoxifen (endoxifen), in breast cancer ERα + cells (MCF-7). METHODS: Two resistant cellular variants, MCF-7Var-H and MCF-7Var-I, were generated by a novel strategy and their phenotype features were evaluated. Phenotypic assessment was performed by MTT assays, cytometry, immunofluorescence microscopy, zymography and protein expression analysis. RESULTS: MCF-7Var-H, generated only with tamoxifen metabolites, showed a critical down-regulation in hormone receptors, augmented migration capacity, metalloprotease 9 extracellular medium excretion, and a mesenchymal morphology in contrast with native MCF-7, suggesting the transition towards Triple-negative breast cancer (TNBC) phenotype. In contrast, MCF-7Var-I which was generated in a high LDL media, showed only a slight upregulation in ER and other less noticeable metabolic adaptations. Results suggest a potential role of transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) in phenotypic differences observed among variants. CONCLUSION: LDL high or low concentrations during Tamoxifen´s metabolites chemoresistance acquisition leads to different cellular mechanisms related to chemoresistance. A novel adaptative cellular response associated with Nrf2 activity could be implicated.
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Resistencia a Medicamentos Antineoplásicos , Receptor alfa de Estrogênio , Lipoproteínas LDL , Fenótipo , Tamoxifeno , Neoplasias de Mama Triplo Negativas , Humanos , Tamoxifeno/farmacologia , Tamoxifeno/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Células MCF-7 , Feminino , Receptor alfa de Estrogênio/metabolismo , Receptor alfa de Estrogênio/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Lipoproteínas LDL/metabolismo , Antineoplásicos Hormonais/farmacologia , Movimento Celular/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacosRESUMO
Insulator-based electrokinetically driven microfluidic devices stimulated with direct current (DC) voltages are an attractive solution for particle separation, concentration, or isolation. However, to design successful particle manipulation protocols, it is mandatory to know the mobilities of electroosmosis, and linear and nonlinear electrophoresis of the microchannel/liquid/particle system. Several techniques exist to characterize the mobilities of electroosmosis and linear electrophoresis. However, only one method to characterize the mobility of nonlinear electrophoresis has been thoroughly assessed, which generally requires DC voltages larger than 1000 V and measuring particle velocity in a straight microchannel. Under such conditions, Joule heating, electrolysis, and the DC power source cost become a concern. Also, measuring particle velocity at high voltages is noisy, limiting characterization quality. Here we present a protocol-tested on 2 µm polystyrene particles-for characterizing the mobility of nonlinear electrophoresis of the liquid/particle system using a DC voltage of only 30 V and visual inspection of particle dynamics in a microchannel featuring insulating obstacles. Multiphysics numerical modelling was used to guide microchannel design and to correlate particle location during an experiment with electric field intensity. The method was validated against the conventional characterization protocol, exhibiting excellent agreement while significantly reducing measurement noise and experimental complexity.
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In recent years, there has been a growing interest in developing portable and personal devices for measuring air quality and surrounding pollutants, partly due to the need for ventilation in the aftermath of COVID-19 situation. Moreover, the monitoring of hazardous chemical agents is a focus for ensuring compliance with safety standards and is an indispensable component in safeguarding human welfare. Air quality measurement is conducted by public institutions with high precision but costly equipment, which requires constant calibration and maintenance by highly qualified personnel for its proper operation. Such devices, used as reference stations, have a low spatial resolution since, due to their high cost, they are usually located in a few fixed places in the city or region to be studied. However, they also have a low temporal resolution, providing few samples per hour. To overcome these drawbacks and to provide people with personalized and up-to-date air quality information, a personal device (smartwatch) based on MEMS gas sensors has been developed. The methodology followed to validate the performance of the prototype was as follows: firstly, the detection capability was tested by measuring carbon dioxide and methane at different concentrations, resulting in low detection limits; secondly, several experiments were performed to test the discrimination capability against gases such as toluene, xylene, and ethylbenzene. principal component analysis of the data showed good separation and discrimination between the gases measured.
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COVID-19 , Dióxido de Carbono , Monitoramento Ambiental , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Humanos , Dióxido de Carbono/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Gases/análise , SARS-CoV-2/isolamento & purificação , Metano/análiseRESUMO
BACKGROUND: Hematopoietic cell transplantation (HCT) is a promising treatment for hematological diseases, yet access barriers like cost and limited transplant centers persist. Telemedicine-based patient navigation (PN) has emerged as a solution. This study presents a cost-free PN telemedicine clinic (TC) in collaboration with the National Marrow Donor Program. AIM: to assess its feasibility and impac on HCT access determined by the cumulative incidence of transplantation. METHODS: In this single-center cohort study, patients of all ages and diagnoses referred for HCT participated. Two transplant physician-navigators established patient relationships via video calls, collecting medical history, offering HCT education and recommending pretransplant tests. The analysis involved descriptive statistics and intent-to-transplant survival assessment. RESULTS: One hundred and three patients were included of whom n = 78 were referred for allogeneic HCT (alloHCT), with a median age of 28 years. The median time from initial contact to the first consult was 5 days. The cumulative incidence of transplantation was 50% at 6 months and 61% at 12 months, with varying outcomes based on HCT type. Notably, 49 patients were not transplanted, primarily due to refractory disease, progression or relapse (57.1%). Autologous HCT candidates and physician referrals were correlated with higher transplant success compared to alloHCT candidates and patients who were not referred by a physician. CONCLUSION: Our pretransplant TC was feasible, facilitating access to HCT. Disease relapse posed a significant barrier. Enhancing timely physician referrals should be a focus for future efforts.
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Electrokinetic (EK) microsystems, which are capable of performing separations without the need for labeling analytes, are a rapidly growing area in microfluidics. The present work demonstrated three distinct binary microbial separations, computationally modeled and experimentally performed, in an insulator-based EK (iEK) system stimulated by DC-biased AC potentials. The separations had an increasing order of difficulty. First, a separation between cells of two distinct domains (Escherichia coli and Saccharomyces cerevisiae) was demonstrated. The second separation was for cells from the same domain but different species (Bacillus subtilis and Bacillus cereus). The last separation included cells from two closely related microbial strains of the same domain and the same species (two distinct S. cerevisiae strains). For each separation, a novel computational model, employing a continuous spatial and temporal function for predicting the particle velocity, was used to predict the retention time (tR,p) of each cell type, which aided the experimentation. All three cases resulted in separation resolution values Rs>1.5, indicating complete separation between the two cell species, with good reproducibility between the experimental repetitions (deviations < 6%) and good agreement (deviations < 18%) between the predicted tR,p and experimental (tR,e) retention time values. This study demonstrated the potential of DC-biased AC iEK systems for performing challenging microbial separations.
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Saccharomyces cerevisiae , Escherichia coli , Dispositivos Lab-On-A-Chip , Bacillus cereus , Técnicas Analíticas Microfluídicas , Separação Celular/métodos , Bacillus subtilisRESUMO
In this study, we examined the role of the lipopolysaccharide (LPS) core of Rhizobium etli in facilitating the adsorption and infection of phages with broad host range. When the plasmid-encoded LPS biosynthesis genes, wreU and wreV, were disrupted, distinct and contrasting effects on phage infection were observed. The wreU mutant strains exhibited wild-type adsorption and infection properties, whereas the wreV mutant demonstrated resistance to phage infection, but retained the capacity to adsorb phages. Complementation of the wreV mutant strains with a recombinant plasmid containing the wreU and wreV, restored the susceptibility to the phages. However, the presence of this recombinant plasmid in a strain devoid of the native lps-encoding plasmid was insufficient to restore phage susceptibility. These results suggest that the absence of wreV impedes the proper assembly of the complete LPS core, potentially affecting the formation of UDP-KdgNAg or KDO precursors for the O-antigen. In addition, a protein not yet identified, but residing in the native lps-encoding plasmid, may be necessary for complete phage infection.
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Bacteriófagos , Especificidade de Hospedeiro , Lipopolissacarídeos , Plasmídeos , Rhizobium etli , Lipopolissacarídeos/biossíntese , Bacteriófagos/genética , Rhizobium etli/genética , Rhizobium etli/virologia , Rhizobium etli/metabolismo , Plasmídeos/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ligação Viral , Teste de Complementação GenéticaRESUMO
BACKGROUND AND OBJECTIVE: Alzheimer's disease (AD) is a neurological disorder that impairs brain functions associated with cognition, memory, and behavior. Noninvasive neurophysiological techniques like magnetoencephalography (MEG) and electroencephalography (EEG) have shown promise in reflecting brain changes related to AD. These techniques are usually assessed at two levels: local activation (spectral, nonlinear, and dynamic properties) and global synchronization (functional connectivity, frequency-dependent network, and multiplex network organization characteristics). Nonetheless, the understanding of the organization formed by the existing relationships between these levels, henceforth named neurophysiological organization, remains unexplored. This work aims to assess the alterations AD causes in the resting-state neurophysiological organization. METHODS: To that end, three datasets from healthy controls (HC) and patients with dementia due to AD were considered: MEG database (55 HC and 87 patients with AD), EEG1 database (51 HC and 100 patients with AD), and EEG2 database (45 HC and 82 patients with AD). To explore the alterations induced by AD in the relationships between several features extracted from M/EEG data, association networks (ANs) were computed. ANs are graphs, useful to quantify and visualize the intricate relationships between multiple features. RESULTS: Our results suggested a disruption in the neurophysiological organization of patients with AD, exhibiting a greater inclination towards the local activation level; and a significant decrease in the complexity and diversity of the ANs (p-value ¡ 0.05, Mann-Whitney U-test, Bonferroni correction). This effect might be due to a shift of the neurophysiological organization towards more regular configurations, which may increase its vulnerability. Moreover, our findings support the crucial role played by the local activation level in maintaining the stability of the neurophysiological organization. Classification performance exhibited accuracy values of 83.91%, 73.68%, and 72.65% for MEG, EEG1, and EEG2 databases, respectively. CONCLUSION: This study introduces a novel, valuable methodology able to integrate parameters characterize different properties of the brain activity and to explore the intricate organization of the neurophysiological organization at different levels. It was noted that AD increases susceptibility to changes in functional neural organization, suggesting a greater ease in the development of severe impairments. Therefore, ANs could facilitate a deeper comprehension of the complex interactions in brain function from a global standpoint.
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Doença de Alzheimer , Encéfalo , Eletroencefalografia , Magnetoencefalografia , Doença de Alzheimer/fisiopatologia , Humanos , Magnetoencefalografia/métodos , Encéfalo/fisiopatologia , Idoso , Masculino , Feminino , Estudos de Casos e Controles , Bases de Dados FactuaisRESUMO
Dyslipidemias involving high concentrations of low-density lipoproteins (LDLs) increase the risk of developing triple-negative breast cancer (TNBC), wherein cholesterol metabolism and protein translation initiation mechanisms have been linked with chemoresistance. Doxorubicin (Dox) treatment, a member of the anthracycline family, represents a typical therapeutic strategy; however, chemoresistance remains a significant challenge. Exosomes (Exs) secreted by tumoral cells have been implicated in cell communication pathways and chemoresistance mechanisms; the content of exosomes is an outcome of cellular cholesterol metabolism. We previously induced Dox resistance in TNBC cell models, characterizing a variant denominated as variant B cells. Our results suggest that LDL internalization in parental and chemoresistant variant B cells is associated with increased cell proliferation, migration, invasion, and spheroid growth. We identified the role of eIF4F translation initiation factor and the down-regulation of tumor suppressor gene PDCD4, an inhibitor of eIF4A, in chemoresistant variant B cells. In addition, the exomes secreted by variant B cells were characterized by the protein content, electronic microscopy, and cell internalization assays. Critically, exosomes purified from LDL-treated variant B cell promoted cell proliferation, migration, and an increment in lactate concentration. Our results suggest that an autocrine phenomenon induced by exosomes in chemoresistant cells may induce modifications on signaling mechanisms of the p53/Mdm2 axis and activation of p70 ribosomal protein kinase S6. Moreover, the specific down-regulated profile of chaperones Hsp90 and Hsp70 secretion inside the exosomes of the chemoresistant variant could be associated with this phenomenon. Therefore, autocrine activation mediated by exosomes and the effect of LDL internalization may influence changes in exosome chaperone content and modulate proliferative signaling pathways, increasing the aggressiveness of MDA-MB-231 chemoresistant cells.
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The central nervous system is essential for maintaining homeostasis and controlling the body's physiological functions. However, its biochemical characteristics make it highly vulnerable to oxidative damage, which is a common factor in neurodegenerative diseases like amyotrophic lateral sclerosis (ALS). ALS is a leading cause of motor neuron disease, characterized by a rapidly progressing and incurable condition. ALS often results in death from respiratory failure within 3-5 years from the onset of the first symptoms, underscoring the urgent need to address this medical challenge. The aim of this study is to present available data supporting the role of oxidative stress in the mechanisms underlying ALS and to discuss potential antioxidant therapies currently in development. These therapies aim to improve the quality of life and life expectancy for patients affected by this devastating disease.
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Purpose: The safety and efficacy of a novel topical ocular anesthetic (AG-920 sterile ophthalmic solution, 8%) was previously evaluated in adults. For both clinical and regulatory purposes, this new agent was evaluated in children. Methods: This was a Phase 3, randomized, active-controlled, single-masked, parallel-group design study in healthy pediatric subjects performed at a private practice retina clinic in the United States. The safety and anesthetic efficacy of AG-920 was compared with proparacaine hydrochloride ophthalmic solution 0.5% in 60 children undergoing ophthalmic examinations. The primary efficacy endpoint was whether the investigator was able to perform the eye examination. Results: In all subjects in each treatment group, the investigator was able to perform the eye examination without additional local anesthetic. There were no adverse events reported in this study. In both the study eye and fellow eye, there were no notable changes after dosing, and both treatment groups were similar. All external eye exams in all subjects in both treatment groups were normal. Conclusions: In this pediatric population aged 7 months to >11 years, AG-920 was therapeutically equivalent to marketed proparacaine with respect to having an ophthalmic examination performed without needing additional local anesthetic. Further, AG-920 was well tolerated, and there were no clinically significant safety findings.
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Anestésicos Locais , Soluções Oftálmicas , Humanos , Criança , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/efeitos adversos , Anestésicos Locais/administração & dosagem , Anestésicos Locais/efeitos adversos , Feminino , Masculino , Pré-Escolar , Lactente , Propoxicaína/administração & dosagem , Propoxicaína/efeitos adversos , Método Simples-Cego , AdolescenteRESUMO
There is a growing interest in the advancement of microscale electrokinetic (EK) systems for biomedical and clinical applications, as these systems offer attractive characteristics such as portability, robustness, low sample requirements and short response time. The present work is focused on manipulating the characteristics of the insulating post arrangement in insulator-based EK (iEK) systems for separating a binary mixture of spherical microparticles with same diameter (5.1 µm), same shape, made from the same substrate material and only differing in their zeta potential by â¼14 mV. This study presents a combination of mathematical modeling and experimental separations performed by applying a low-frequency alternating current (AC) voltage in iEK systems with 12 distinct post arrangements. These iEK devices were used to systematically study the effect of three spatial characteristics of the insulating post array on particle separations: the horizontal separation and the vertical separation between posts, and introducing an offset to the posts arrangement. Through normalization of the spatial separation between the insulating posts with respect to particle diameter, guidelines to improve separation resolution for different particle mixtures possessing similar characteristics were successfully identified. The results indicated that by carefully designing the spatial arrangement of the post array, separation resolution values in the range of 1.4-2.8 can be obtained, illustrating the importance and effect of the arrangement of insulating posts on improving particle separations. This study demonstrates that iEK devices, with effectively designed spatial arrangement of the insulating post arrays, have the capabilities to perform discriminatory separations of microparticles of similar characteristics.
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Hyperfluorescence shows great promise for the next generation of commercially feasible blue organic light-emitting diodes, for which eliminating the Dexter transfer to terminal emitter triplet states is key to efficiency and stability. Current devices rely on high-gap matrices to prevent Dexter transfer, which unfortunately leads to overly complex devices from a fabrication standpoint. Here we introduce a molecular design where ultranarrowband blue emitters are covalently encapsulated by insulating alkylene straps. Organic light-emitting diodes with simple emissive layers consisting of pristine thermally activated delayed fluorescence hosts doped with encapsulated terminal emitters exhibit negligible external quantum efficiency drops compared with non-doped devices, enabling a maximum external quantum efficiency of 21.5%. To explain the high efficiency in the absence of high-gap matrices, we turn to transient absorption spectroscopy. It is directly observed that Dexter transfer from a pristine thermally activated delayed fluorescence sensitizer host can be substantially reduced by an encapsulated terminal emitter, opening the door to highly efficient 'matrix-free' blue hyperfluorescence.
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The vast amount of information stemming from the deployment of the Internet of Things and open data portals is poised to provide significant benefits for both the private and public sectors, such as the development of value-added services or an increase in the efficiency of public services. This is further enhanced due to the potential of semantic information models such as NGSI-LD, which enable the enrichment and linkage of semantic data, strengthened by the contextual information present by definition. In this scenario, advanced data processing techniques need to be defined and developed for the processing of harmonised datasets and data streams. Our work is based on a structured approach that leverages the principles of linked-data modelling and semantics, as well as a data enrichment toolchain framework developed around NGSI-LD. Within this framework, we reveal the potential for enrichment and linkage techniques to reshape how data are exploited in smart cities, with a particular focus on citizen-centred initiatives. Moreover, we showcase the effectiveness of these data processing techniques through specific examples of entity transformations. The findings, which focus on improving data comprehension and bolstering smart city advancements, set the stage for the future exploration and refinement of the symbiosis between semantic data and smart city ecosystems.
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Bees are essential pollinators and understanding their ability to cope with extreme temperature changes is crucial for predicting their resilience to climate change, but studies are limited. We measured the response of the critical thermal maximum (CTMax) to short-term acclimation in foragers of six bee species from the Greek island of Lesvos, which differ in body size, nesting habit, and level of sociality. We calculated the acclimation response ratio as a metric to assess acclimation capacity and tested whether bees' acclimation capacity was influenced by body size and/or CTMax. We also assessed whether CTMax increases following acute heat exposure simulating a heat wave. Average estimate of CTMax varied among species and increased with body size but did not significantly shift in response to acclimation treatment except in the sweat bee Lasioglossum malachurum. Acclimation capacity averaged 9% among species and it was not significantly associated with body size or CTMax. Similarly, the average CTMax did not increase following acute heat exposure. These results indicate that bees might have limited capacity to enhance heat tolerance via acclimation or in response to prior heat exposure, rendering them physiologically sensitive to rapid temperature changes during extreme weather events. These findings reinforce the idea that insects, like other ectotherms, generally express weak plasticity in CTMax, underscoring the critical role of behavioral thermoregulation for avoidance of extreme temperatures. Conserving and restoring native vegetation can provide bees temporary thermal refuges during extreme weather events.