RESUMO
Exosomes are small extracellular membrane particles that play a crucial role in intracellular signaling. Research shows that exosomes have the potential to be used as biomarkers or drug delivery systems in specific organs, such as the neurological system and the inner ear. Exosomes in neurological and auditory systems release different molecules when under stress versus in healthy states, highlighting their potential use as biomarkers in the identification of diseased states. Studies have suggested that exosomes can be harnessed for drug delivery to hard-to-reach organs, such as cochlear sensory hair cells and the brain due to their ability to cross the blood-labyrinth and blood-brain barriers. In this article, we describe the biogenesis, classification, and characterization methods of exosomes. We then discuss recent studies that indicate their potential usage as biomarkers and drug delivery systems to help treat inner ear and neurological disorders.
Assuntos
Biomarcadores/análise , Sistemas de Liberação de Medicamentos , Exossomos/metabolismo , Doenças do Sistema Nervoso/tratamento farmacológico , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos/métodos , HumanosRESUMO
BACKGROUND: Postoperative cardiac arrest (CA) with or without need for extracorporeal cardiopulmonary resuscitation (ECPR) is one of the most significant complications in the early postoperative period after pediatric cardiac operation. The objective of this study was to develop and to validate a predictive model of postoperative CA with or without ECPR. METHODS: In this retrospective cohort study, we reviewed data from patients who underwent cardiac surgery with cardiopulmonary bypass (CPB) between July 20, 2020, and December 31, 2021. Variables included demographic data, presence of preoperative risk factors, The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality categories, perioperative data, residual lesion score (RLS), and vasoactive-inotropic score (VIS). We used multivariable logistic regression analysis to develop a predictive model. RESULTS: The incidence of CA with or without ECPR was 4.4% (n = 24/544). Patients who experienced postoperative CA with or without ECPR were younger (age, 130 [54-816.5] days vs 626 [127.5-2497.5] days; P < .050) and required longer CPB (253 [154-332.5] minutes vs 130 [87-186] minutes; P < .010) and cross-clamp (116.5 [75.5-143.5] minutes vs 64 [30-111] minutes; P < .020) times; 37.5% of patients with an outcome had at least 1 preoperative risk factor (vs 16.9%; P < .010). Our multivariable logistic regression determined that the presence of at least 1 preoperative risk factor (P = .005), CPB duration (P = .003), intraoperative residual lesion score (P = .009), and postsurgery vasoactive-inotropic score (P = .010) were predictors of the incidence of CA with or without ECPR. CONCLUSIONS: We developed a predictive model of postoperative CA with or without ECPR after congenital cardiac operation. Our model performed better than the individual scores and risk factors.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca , Cirurgia Torácica , Criança , Humanos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Reanimação Cardiopulmonar/efeitos adversos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Parada Cardíaca/epidemiologia , Parada Cardíaca/etiologia , Parada Cardíaca/terapia , Estudos Retrospectivos , Lactente , Pré-EscolarRESUMO
BACKGROUND: Incorporating opportunities for community engagement into undergraduate medical education (UME) can help learners to identify and address social determinants of health (SDoH). Multiple challenges exist in operationalizing these experiences. METHODS: Using the Assessing Community Engagement (ACE) model, course directors at the Warren Alpert Medical School of Brown University (AMS) mapped community engagement initiatives to the four-year curriculum. FINDINGS: Service-learning, community engagement projects, and clinical rotations at health centers and free clinics aim to equip learners at AMS with the necessary skills to address SDoH. Careful consideration should be given to the time and resources required to facilitate relationships with community-based agencies, learner reflection, program evaluation, and community-level outcomes. CONCLUSIONS: Community engagement activities should be aligned with learning objectives during the pre-clerkship and clerkship stages of the existing UME curricula. Embarking on a curriculum redesign can create opportunities to expand partnerships with local agencies and deepen student engagement.
Assuntos
Educação de Graduação em Medicina , Educação Médica , Humanos , Faculdades de Medicina , Currículo , Instituições de Assistência AmbulatorialRESUMO
PURPOSE: Both traditional cardiac rehabilitation (TCR) and intensive cardiac rehabilitation (ICR) have proven benefits for patients with cardiovascular disease. The aim of this study was to compare ICR versus TCR on cardiac rehabilitation (CR) outcomes in patients with cardiovascular disease. METHODS: In a retrospective cohort study of 970 patients (n = 251, ICR; n = 719, TCR) who were referred for CR between January 2018 and December 2019, 693 (71.4%) patients completed it. The TCR sessions were 90 min (60-min exercise) three times/wk for 12 wk, while ICR sessions were 4 hr (60-min exercise) two times/wk for 9 wk. Primary endpoints were change in cardiorespiratory fitness (CRF) (by difference in exercise prescription metabolic equivalents [METs] between the last session and the average of the second and third sessions), anxiety (Generalized Anxiety Disorder-7) scores, percent depression (Patient Health Questionnaire-9 or Center for Epidemiologic Studies Depression Scale) scores, and health status (36-item Short Form Health Survey physical and mental composite scores). Linear regression adjusted for imbalanced baseline characteristics (age, race, and diagnosis of angina). RESULTS: Of the 693 patients who completed CR (ICR = 204/251 [81%] vs TCR = 489/719 [68%], P < .01), mean age was 66 yr and 31% were female. Patients in TCR had a higher improvement in CRF (CR session METs: ICR +1.5 ± 1.2 vs TCR +1.9 ± 1.5, P < .01) but no difference in health status scores. Conversely, patients in ICR had more reduction in anxiety scores (-2 ± 4 vs -1 ± 3, P < .01) and percent reduction in depression scores (-8.3 ± 13.7% vs -5.0 ± 11.7%, P < .01) than patients in TCR. CONCLUSIONS: Patients in TCR had higher improvement in CRF while patients in ICR had higher improvement in anxiety and depression scores.
Assuntos
Reabilitação Cardíaca , Doenças Cardiovasculares , Humanos , Feminino , Idoso , Masculino , Estudos Retrospectivos , Exercício Físico , Terapia por Exercício , Receptores de Antígenos de Linfócitos TRESUMO
PURPOSE: Physical inactivity, a modifiable risk factor for cardiovascular disease, is independently associated with stroke. Though some prior data have suggested sex differences in levels of physical activity, whether there are sex differences in the role of physical activity in primary stroke prevention is largely unknown. This systematic review identifies and describes recent findings on sex differences in the association between physical activity and incident (first-ever) stroke. This review also describes the current evidence on the strength of the association between physical activity and a reduced stroke risk in women in particular. METHODS: Using a prespecified strategy, PubMed/MEDLINE and Cochrane Central were searched to identify observational studies or trials published from 2000 to 2020 and reporting sex differences in physical activity and incident stroke. To be included, among other criteria, studies had to include sex-specific effect estimates from women, men, or both. Titles, abstracts, and full-text articles were screened to identify studies meeting the inclusion criteria, and adjusted sex-specific estimates of the association between physical activity and incident stroke for total stroke (ischemic plus hemorrhagic) or ischemic stroke were abstracted. FINDINGS: Thirty-seven studies met the inclusion criteria. Of 17 studies that included data on total incident stroke (ischemic and hemorrhagic combined) in both women and men, 7 (41%) showed similar associations between physical activity and incident stroke between women and men, 6 (35%) suggested a significant effect in women but not in men, and 3 (18%) showed a significant effect in men but not in women. Of 10 studies that included data on ischemic stroke in women and men, 5 (50%) suggested similar effects in women and men, 4 (40%) suggested a significant effect in women but not in men, and 1 (10%) showed an effect in men but not women. In women specifically, the majority of included studies demonstrated a reduced risk for incident stroke with physical activity, with relative risk reductions ranging from 11% to 72%, though most estimates fell between 20% and 40%. IMPLICATIONS: The majority of studies indicated a clear association between physical activity and a reduction in stroke risk. Studies were split as to the potential for sex differences in this association. Future prospective investigations should identify strategies for the use of increased physical activity for primary stroke prevention, with sex-specific considerations as warranted. The data on sex-specific dose-response relationship between physical activity and stroke risk are inconclusive and warrant more research.
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AVC Isquêmico , Acidente Vascular Cerebral , Exercício Físico , Feminino , Humanos , Masculino , Fatores de Risco , Caracteres Sexuais , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controleRESUMO
Major advancements in targeted gene therapy have opened up avenues for the treatment of major neurological disorders through a range of versatile modalities varying from expression of exogenous to suppression of endogenous genes. Recent technological innovations for improved gene sequence delivery have focussed on highly specific viral vector designs, plasmid transfection, nanoparticles, polymer-mediated gene delivery, engineered microRNA and in vivo clustered regulatory interspaced short palindromic repeats (CRISPR)-based therapeutics. These advanced techniques have profound applications in treating highly prevalent neurological diseases and neurodevelopmental disorders including Parkinson's disease, Alzheimer's disease and autism spectrum disorder, as well as rarer diseases such as amyotrophic lateral sclerosis (ALS), spinal muscular atrophy, lysosomal storage diseases, X-linked adrenoleukodystrophy and oncological diseases. In this article, we present an overview of the latest advances in targeted gene delivery and discuss the challenges and future direction of gene therapy in the treatment of neurological disorders.
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Técnicas de Transferência de Genes , Terapia Genética/métodos , Doenças do Sistema Nervoso/terapia , Animais , Sistemas CRISPR-Cas/genética , Vetores Genéticos , Humanos , Nanopartículas , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/fisiopatologia , Polímeros/químicaRESUMO
Sensorineural deafness in mammals is most commonly caused by damage to inner ear sensory epithelia, or hair cells, and can be attributed to genetic and environmental causes. After undergoing trauma, many non-mammalian organisms, including reptiles, birds, and zebrafish, are capable of regenerating damaged hair cells. Mammals, however, are not capable of regenerating damaged inner ear sensory epithelia, so that hair cell damage is permanent and can lead to hearing loss. The field of epigenetics, which is the study of various phenotypic changes caused by modification of genetic expression rather than alteration of DNA sequence, has seen numerous developments in uncovering biological mechanisms of gene expression and creating various medical treatments. However, there is a lack of information on the precise contribution of epigenetic modifications in the auditory system, specifically regarding their correlation with development of inner ear (cochlea) and consequent hearing impairment. Current studies have suggested that epigenetic modifications influence differentiation, development, and protection of auditory hair cells in cochlea, and can lead to hair cell degeneration. The objective of this article is to review the existing literature and discuss the advancements made in understanding epigenetic modifications of inner ear sensory epithelial cells. The analysis of the emerging epigenetic mechanisms related to inner ear sensory epithelial cells development, differentiation, protection, and regeneration will pave the way to develop novel therapeutic strategies for hearing loss.
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Células Ciliadas Auditivas/citologia , Células Ciliadas Auditivas/fisiologia , Perda Auditiva Neurossensorial/genética , Animais , Diferenciação Celular/genética , Surdez/genética , Orelha Interna/crescimento & desenvolvimento , Epigênese Genética , Células Ciliadas Auditivas Internas/citologia , Células Ciliadas Auditivas Internas/fisiologia , Perda Auditiva/genética , Humanos , Regeneração/genéticaRESUMO
The progressive, late-onset, nonsyndromic, sensorineural hearing loss (PNSHL) is the most common cause of sensory impairment globally, with presbycusis affecting greater than a third of individuals over the age of 65. The etiology underlying PNSHL include presbycusis, noise-induced hearing loss, drug ototoxicity, and delayed-onset autosomal dominant hearing loss (AD PNSHL). The objective of this article is to discuss the potential diagnostic and therapeutic applications of genomic medicine in PNSHL. Genomic factors contribute greatly to PNSHL. The heritability of presbycusis ranges from 25 to 75%. Current therapies for PNSHL range from sound amplification to cochlear implantation (CI). PNSHL is an excellent candidate for genomic medicine approaches as it is common, has well-described pathophysiology, has a wide time window for treatment, and is amenable to local gene therapy by currently utilized procedural approaches. AD PNSHL is especially suited to genomic medicine approaches that can disrupt the expression of an aberrant protein product. Gene therapy is emerging as a potential therapeutic strategy for the treatment of PNSHL. Viral gene delivery approaches have demonstrated promising results in human clinical trials for two inherited causes of blindness and are being used for PNSHL in animal models and a human trial. Non-viral gene therapy approaches are useful in situations where a transient biologic effect is needed or for delivery of genome editing reagents (such as CRISPR/Cas9) into the inner ear. Many gene therapy modalities that have proven efficacious in animal trials have potential to delay or prevent PNSHL in humans. The development of new treatment modalities for PNSHL will lead to improved quality of life of many affected individuals and their families.
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Terapia Genética , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/terapia , Análise Custo-Benefício , Epigênese Genética , Técnicas de Transferência de Genes , Terapia Genética/economia , Perda Auditiva Neurossensorial/genética , HumanosRESUMO
The etiology of hearing loss tends to be multi-factorial and affects a significant proportion of the global population. Despite the differences in etiology, a common physical pathological change that leads to hearing loss is damage to the mechanosensory hair cells of the inner ear. MicroRNAs (miRNAs) have been shown to play a role in inner ear development and thus, may play a role in the development or prevention of hearing loss. In this paper, we review the mechanism of action of miRNAs in the auditory system. We present an overview about the role of miRNAs in inner ear development, summarize the current research on the role of miRNAs in gene regulation, and discuss the effects of both miRNA mutations as well as overexpression. We discuss the crucial role of miRNAs in ensuring normal physiological development of the inner ear. Any deviation from the proper function of miRNA in the cochlea seems to contribute to deleterious damage to the structure of the auditory system and subsequently results in hearing loss. As interest for miRNA research increases, this paper serves as a platform to review current understandings and postulate future avenues for research. A better knowledge about the role of miRNA in the auditory system will help in developing novel treatment modalities for restoring hearing function based on regeneration of damaged inner ear hair cells.