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1.
JMIR Cancer ; 9: e39631, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36719719

RESUMO

BACKGROUND: Precision health offers the promise of advancing clinical care in data-driven, evidence-based, and personalized ways. However, complex data sharing infrastructures, for-profit (commercial) and nonprofit partnerships, and systems for data governance have been created with little attention to the values, expectations, and preferences of patients about how they want to be engaged in the sharing and use of their health information. We solicited patient opinions about institutional policy options using public deliberation methods to address this gap. OBJECTIVE: We aimed to understand the policy preferences of current and former patients with cancer regarding the sharing of health information collected in the contexts of health information exchange and commercial partnerships and to identify the values invoked and perceived risks and benefits of health data sharing considered by the participants when formulating their policy preferences. METHODS: We conducted 2 public deliberations, including predeliberation and postdeliberation surveys, with patients who had a current or former cancer diagnosis (n=61). Following informational presentations, the participants engaged in facilitated small-group deliberations to discuss and rank policy preferences related to health information sharing, such as the use of a patient portal, email or SMS text messaging, signage in health care settings, opting out of commercial data sharing, payment, and preservation of the status quo. The participants ranked their policy preferences individually, as small groups by mutual agreement, and then again individually in the postdeliberation survey. RESULTS: After deliberation, the patient portal was ranked as the most preferred policy choice. The participants ranked no change in status quo as the least preferred policy option by a wide margin. Throughout the study, the participants expressed concerns about transparency and awareness, convenience, and accessibility of information about health data sharing. Concerns about the status quo centered around a lack of transparency, awareness, and control. Specifically, the patients were not aware of how, when, or why their data were being used and wanted more transparency in these regards as well as greater control and autonomy around the use of their health data. The deliberations suggested that patient portals would be a good place to provide additional information about data sharing practices but that over time, notifications should be tailored to patient preferences. CONCLUSIONS: Our study suggests the need for increased disclosure of health information sharing practices. Describing health data sharing practices through patient portals or other mechanisms personalized to patient preferences would minimize the concerns expressed by patients about the extent of data sharing that occurs without their knowledge. Future research and policies should identify ways to increase patient control over health data sharing without reducing the societal benefits of data sharing.

2.
Genet Med ; 25(1): 115-124, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36371759

RESUMO

PURPOSE: Genetic researchers' selection of a database can have scientific, regulatory, and ethical implications. It is important to understand what is driving database selection such that database stewards can be responsive to user needs while balancing the interests of communities in equitably benefiting from advances. METHODS: We conducted 23 semistructured interviews with US academic genetic researchers working with private, government, and collaboratory data stewards to explore factors that they consider when selecting a genetic database. RESULTS: Interviewees used existing databases to avoid burdens of primary data collection, which was described as expensive and time-consuming. They highlighted ease of access as the most important selection factor, integrating concepts of familiarity and efficiency. Data features, such as size and available phenotype, were also important. Demographic diversity was not originally cited by any interviewee as a pivotal factor; when probed, most stated that the option to consider diversity in database selection was limited. Database features, including integrity, harmonization, and storage were also described as key components of efficient use. CONCLUSION: There is a growing market and competition between genetic data stewards. Data need to be accessible, harmonized, and administratively supported for their existence to be translated into use and, in turn, result in scientific advancements across diverse communities.


Assuntos
Disseminação de Informação , Pesquisadores , Humanos
3.
Genes (Basel) ; 13(11)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36421832

RESUMO

Lung and breast cancer are the two most common causes of malignant pleural effusion (MPE). MPE diagnosis plays a crucial role in determining staging and therapeutic interventions in these cancers. However, our understanding of the pathogenesis and progression of MPE at the molecular level is limited. Extracellular Vesicles (EVs) and their contents, including microRNAs (miRNAs), can be isolated from all bodily fluids, including pleural fluid. This study aims to compare EV-miRNA patterns of expression in MPE caused by breast (BA-MPE) and lung (LA-MPE) adenocarcinomas compared to the control group of heart-failure-induced effusions (HF-PE). We conducted an analysis of 24 pleural fluid samples (8 LA-MPE, 8 BA-MPE, and 8 HF-PE). Using NanoString technology, we profiled miRNAs within EVs isolated from 12 cases. Bioinformatic analysis demonstrated differential expression of miR-1246 in the MPE group vs. HF-PE group and miR-150-5p and miR-1246 in the BA-MPE vs. LA-MPE group, respectively. This difference was demonstrated and validated in an independent cohort using real-time PCR (RT-PCR). miRNA-1246 demonstrated 4-fold increased expression (OR: 3.87, 95% CI: 0.43, 35) in the MPE vs. HF-PE group, resulting in an area under the curve of 0.80 (95% CI: 0.60, 0.99). The highest accuracy for differentiating MPE vs. HF-PE was seen with a combination of miRNAs compared to each miRNA alone. Consistent with prior studies, this study demonstrates dysregulation of specific EV-based miRNAs in breast and lung cancer; pleural fluid provides direct access for the analysis of these EV-miRNAs as biomarkers and potential targets and may provide insight into the underlying pathogenesis of tumor progression. These findings should be explored in large prospective studies.


Assuntos
Vesículas Extracelulares , Neoplasias Pulmonares , MicroRNAs , Derrame Pleural Maligno , Humanos , Derrame Pleural Maligno/genética , Derrame Pleural Maligno/diagnóstico , Derrame Pleural Maligno/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Estudos Prospectivos , Vesículas Extracelulares/metabolismo , Neoplasias Pulmonares/metabolismo
4.
JMIR Cancer ; 8(3): e37793, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36112409

RESUMO

BACKGROUND: Precision oncology is one of the fastest-developing domains of personalized medicine and is one of many data-intensive fields. Policy for health information sharing that is informed by patient perspectives can help organizations align practice with patient preferences and expectations, but many patients are largely unaware of the complexities of how and why clinical health information is shared. OBJECTIVE: This paper evaluates the process of public deliberation as an approach to understanding the values and preferences of current and former patients with cancer regarding the use and sharing of health information collected in the context of precision oncology. METHODS: We conducted public deliberations with patients who had a current or former cancer diagnosis. A total of 61 participants attended 1 of 2 deliberative sessions (session 1, n=28; session 2, n=33). Study team experts led two educational plenary sessions, and trained study team members then facilitated discussions with small groups of participants. Participants completed pre- and postdeliberation surveys measuring knowledge, attitudes, and beliefs about precision oncology and data sharing. Following informational sessions, participants discussed, ranked, and deliberated two policy-related scenarios in small groups and in a plenary session. In the analysis, we evaluate our process of developing the deliberative sessions, the knowledge gained by participants during the process, and the extent to which participants reasoned with complex information to identify policy preferences. RESULTS: The deliberation process was rated highly by participants. Participants felt they were listened to by their group facilitator, that their opinions were respected by their group, and that the process that led to the group's decision was fair. Participants demonstrated improved knowledge of health data sharing policies between pre- and postdeliberation surveys, especially regarding the roles of physicians and health departments in health information sharing. Qualitative analysis of reasoning revealed that participants recognized complexity, made compromises, and engaged with trade-offs, considering both individual and societal perspectives related to health data sharing. CONCLUSIONS: The deliberative approach can be valuable for soliciting the input of informed patients on complex issues such as health information sharing policy. Participants in our two public deliberations demonstrated that giving patients information about a complex topic like health data sharing and the opportunity to reason with others and discuss the information can help garner important insights into policy preferences and concerns. Data on public preferences, along with the rationale for information sharing, can help inform policy-making processes. Increasing transparency and patient engagement is critical to ensuring that data-driven health care respects patient autonomy and honors patient values and expectations.

5.
J Neurosci ; 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35803734

RESUMO

DYRK1A triplication in Down's Syndrome (DS) and its overexpression in Alzheimer's Disease (AD) suggest a role for increased DYR1A activity in the abnormal metabolism of APP. Transport defects are early phenotypes in the progression of AD, which lead to APP processing impairments. However, whether DYRK1A regulates the intracellular transport and delivery of APP in human neurons remains unknown. From a proteomic dataset of human cerebral organoids treated with harmine, a DYRK1A inhibitor, we found expression changes in protein clusters associated with the control of microtubule-based transport and in close interaction with the APP vesicle. Live-imaging of APP axonal transport in human-derived neurons treated with harmine or overexpressing a dominant negative DYRK1A revealed a reduction in APP vesicle density and enhanced the stochastic behavior of retrograde vesicle transport. Moreover, harmine increased the fraction of slow segmental velocities and changed speed transitions supporting a DYRK1A-mediated effect in the exchange of active motor configuration. Contrarily, the overexpression of DYRK1A in human polarized neurons increased the axonal density of APP vesicles and enhanced the processivity of retrograde APP. In addition, increased DYRK1A activity induced faster retrograde segmental velocities together with significant changes in slow to fast anterograde and retrograde speeds transitions suggesting the facilitation of the active motor configuration. Our results highlight DYRK1A as a modulator of the axonal transport machinery driving APP intracellular distribution in neurons, and stress DYRK1A inhibition as a putative therapeutic intervention to restore APP axonal transport in DS and AD.Significance StatementAxonal transport defects are early events in the progression of neurodegenerative diseases such as Alzheimer's Disease (AD). However, the molecular mechanisms underlying transport defects remain elusive. DYRK1A kinase is triplicated in Down's Syndrome and overexpressed in AD, suggesting that DYRK1A dysfunction affects molecular pathways leading to early-onset neurodegeneration. Here, we show by live imaging of human-derived neurons that DYRK1A activity differentially regulates the intracellular trafficking of the amyloid precursor protein (APP). Further, single particle analysis revealed DYRK1A as a modulator of axonal transport and the configuration of active motors within the APP vesicle. Our work highlights DYRK1A as a regulator of APP axonal transport and metabolism; supporting DYRK1A inhibition as a therapeutic strategy to restore intracellular dynamics in AD.

7.
J Clin Transl Sci ; 6(1): e136, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36590362

RESUMO

Introduction: The COVID-19 pandemic accelerated a trend for clinical and translational community-engaged research in adapting to an increasingly virtual landscape. This requires a framework for engagement distinct from in-person research and program activities. We reflect on four case studies of community engagement activities that inform a conceptual framework to better integrate the virtual format into community-engaged research reflecting key tenets of health equity and antiracist praxis. Methods: Four projects were selected by community-engaged research stakeholders for an in-depth review based on how much the virtual transition impacted activities such as planning, recruitment, and data collection for each project. Transitions to virtual engagement were assessed across ten areas in which community engagement has been demonstrated to make a positive impact. Results: Our analysis suggests a conceptual evaluation framework in which the ten community engagement areas cluster into four interrelated domains: (1) development, design, and delivery; (2) partnership and trust building; (3) implementation and change; and (4) ethics and equity. Conclusions: The domains in this conceptual framework describe critical elements of community engaged research and programs consistent with recommendations for health equity informed meaningful community engagement from the National Academy of Medicine. The conceptual framework and case studies can be used for evaluation and to develop guidelines for clinical and translational researchers utilizing the virtual format in community-engaged research.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33916388

RESUMO

Previous studies have shown that planned home birth in low-risk pregnancies is a generally safe option. However nowadays, only 0.5 percent of deliveries have been at home in Spain. This study sought to understand the characteristics of planned home births with qualified healthcare professionals in low-risk pregnancies and their results on maternal and neonatal health in the Balearic Islands. The study followed a retrospective descriptive design to investigate planned home births from 1989 to 2019 (n = 820). Sociodemographic data of women, healthcare professional intervention rates, and maternal/fetal morbidity/mortality results were collected. Statistical analysis of the results was performed using the IBM SPSS Version 25 software package. The results indicated that women with low-risk pregnancies who planned home births with a qualified midwife had a higher probability of spontaneous vaginal birth delivery and positive maternal health results. Furthermore, the risk of hospital transfer was low (10.7%) and the rate of prolonged breastfeeding (>1 year) was extremely high (99%). Moreover, the study showed that planned home births can be generally associated with fetal well-being. The conclusions and implications of this study are that planned home births in low-risk pregnancies attended by qualified midwives in the Balearic Islands achieve positive results in both maternal and newborn health, as well as low rates of obstetric intervention.


Assuntos
Parto Domiciliar , Tocologia , Parto Obstétrico , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos , Espanha
9.
J Bronchology Interv Pulmonol ; 28(3): 192-200, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33443966

RESUMO

BACKGROUND: Although thoracentesis can offer considerable symptomatic relief to the patient, its physiologic impact on oxygen saturation has not been well established in the literature. This study aimed to evaluate the impact of thoracentesis on postprocedure pulse oximetry (SpO2) in an inpatient population. METHODS: A retrospective study of patients undergoing thoracentesis from January 2012 to November 2017 was performed. Inclusion criteria were age above 18 and thoracentesis performed in an inpatient setting. Records were reviewed for patient demographics, procedure reports, and laboratory values. SpO2 and FiO2 values were collected before and 6 and 24 hours postprocedure. Multivariable linear regression models were used to evaluate for changes in SpO2 and SpO2/FiO2. Analyses were adjusted for age, sex, serum hemoglobin, effusion etiology, volume removed, nonexpandable lung physiology and procedural complications and FiO2. RESULTS: A total of 502 patients were included. The mean (SD) age was 60 (14) years, and 53.4% of the patients were male. The most common cause of pleural effusion was malignant effusion (37%). The median (interquartile range) volume of fluid removed was 1400 (1000 to 2000) mL and nonexpandable lung physiology was noted in 35%. There was no significant within-subject difference in 24 hours postprocedure SpO2 compared with preprocedure SpO2. In multivariable analysis, there was a small increase in 24-hour postprocedure SpO2 [ß=0.31, 95% confidence interval (0.22, 0.41), P<0.01] and a similar small increase in 24-hour postprocedure SpO2/FiO2 [ß=0.84, 95% confidence interval: (0.68, 1.01), P<0.01). CONCLUSION: Among inpatients undergoing thoracentesis, there is no clinically significant change in SpO2 or SpO2/FiO2 at 24-hours post-procedure compared to pre-procedural SpO2 or SpO2/FiO2.


Assuntos
Oximetria , Toracentese , Procedimentos Cirúrgicos Torácicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio , Estudos Retrospectivos
11.
Ann Am Thorac Soc ; 18(4): 606-612, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33026887

RESUMO

Rationale: Patients with malignant or paramalignant pleural effusions (MPEs or PMPEs) may have tunneled pleural catheter (TPC) management withheld because of infection concerns from immunosuppression associated with antineoplastic therapy.Objectives: To determine the rate of infections related to TPC use and to determine the relationship to antineoplastic therapy, immune system competency, and overall survival (OS).Methods: We performed an international, multiinstitutional study of patients with MPEs or PMPEs undergoing TPC management from 2008 to 2016. Patients were stratified by whether or not they underwent antineoplastic therapy and/or whether or not they were immunocompromised. Cumulative incidence functions and multivariable competing risk regression analyses were performed to identify independent predictors of TPC-related infection. Kaplan-Meier method and multivariable Cox proportional hazards modeling were performed to examine for independent effects on OS.Results: A total of 1,408 TPCs were placed in 1,318 patients. Patients had a high frequency of overlap between antineoplastic therapy and an immunocompromised state (75-83%). No difference in the overall (6-7%), deep pleural (3-5%), or superficial (3-4%) TPC-related infection rates between subsets of patients stratified by antineoplastic therapy or immune status was observed. The median time to infection was 41 (interquartile range, 19-87) days after TPC insertion. Multivariable competing risk analyses demonstrated that longer TPC duration was associated with a higher risk of TPC-related infection (subdistribution hazard ratio, 1.03; 95% confidence interval [CI], 1.00-1.06; P = 0.028). Cox proportional hazards analysis showed antineoplastic therapy was associated with better OS (hazard ratio, 0.84; 95% CI, 0.73-0.97; P = 0.015).Conclusions: The risk of TPC-related infection does not appear to be increased by antineoplastic therapy use or an immunocompromised state. The overall rates of infection are low and comparable with those of immunocompetent patients with no relevant antineoplastic therapy. These results support TPC palliation for MPE or PMPEs regardless of plans for antineoplastic therapy.


Assuntos
Antineoplásicos , Derrame Pleural Maligno , Antineoplásicos/efeitos adversos , Cateteres de Demora , Drenagem , Humanos , Pleurodese
12.
Development ; 147(8)2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32265198

RESUMO

Endocannabinoids (eCB) modulate growth cone dynamics and axonal pathfinding through the stimulation of cannabinoid type-1 receptors (CB1R), the function of which depends on their delivery and precise presentation at the growth cone surface. However, the mechanism involved in the axonal transport of CB1R and its transport role in eCB signaling remains elusive. As mutations in the kinesin-1 molecular motor have been identified in patients with abnormal cortical development and impaired white matter integrity, we studied the defects in axonal pathfinding and fasciculation in mice lacking the kinesin light chain 1 (Klc1-/-) subunit of kinesin-1. Reduced levels of CB1R were found in corticofugal projections and axonal growth cones in Klc1-/- mice. By live-cell imaging of CB1R-eGFP we characterized the axonal transport of CB1R vesicles and described the defects in transport that arise after KLC1 deletion. Cofilin activation, which is necessary for actin dynamics during growth cone remodeling, is impaired in the Klc1-/- cerebral cortex. In addition, Klc1-/- neurons showed expanded growth cones that were unresponsive to CB1R-induced axonal elongation. Together, our data reveal the relevance of kinesin-1 in CB1R axonal transport and in eCB signaling during brain wiring.


Assuntos
Transporte Axonal , Axônios/metabolismo , Canabinoides/metabolismo , Cinesinas/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Animais , Axônios/ultraestrutura , Córtex Cerebral/metabolismo , Deleção de Genes , Cones de Crescimento/metabolismo , Camundongos Endogâmicos C57BL , Subunidades Proteicas/metabolismo , Tálamo/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-34337435

RESUMO

Healthcare systems are using big data-driven methods to realize the vision of learning health systems and improve care quality. In so doing, many are partnering with third-party commercial companies to provide novel data processing and analysis capabilities, while also providing personal health information to a for-profit industry that may store and sell data. In this research we describe the public's comfort with sharing health data with third-party commercial companies for patient and business purposes and how this comfort is associated with demographic factors (sex, age, race/ethnicity, education, employment, income, insurance status, and self-reported health status), perceived healthcare access, and concerns about privacy. We surveyed the US public (n = 1841) to assess comfort with sharing health data with third-party commercial companies for patient or business purposes and examined whether there was a difference between comfort with data sharing for patient or business purposes. Univariate and stepwise regression modeling is used here to estimate the relationship between comfort with third-party commercial companies for patient and business purposes (outcomes) and demographic factors, self-reported health status, perceived healthcare access, and privacy concerns. The public is more comfortable sharing health data with third party commercial companies for patient purposes as compared to business purposes (paired t = 39.84, p < 0.001). Higher education was associated with greater comfort with sharing health data for patient purposes (ß = 0.205, p < 0.001) and decreased comfort with sharing health data for business purposes (ß = -0.145, p = 0.079). An inverse relationship exists between privacy concerns and comfort with sharing health data for both patient (ß = -0.223, p < 0.001) and business purposes (ß = -0.246, p < 0.001). Participants ages 45-59 were less comfortable sharing health data with third party commercial companies for patient purposes (ß = -0.154, p = 0.0012) than participants aged 18-29. Proactive acknowledgment of privacy concerns and better communication of the steps being taken to protect the privacy of health data can increase patient comfort. Healthcare systems may be able to increase public and patient comfort with sharing health data with third-party commercial companies by emphasizing the patient-centered benefits of these partnerships.

14.
Chest ; 157(3): 702-711, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31711990

RESUMO

BACKGROUND: Thoracentesis can be accomplished by active aspiration or drainage with gravity. This trial investigated whether gravity drainage could protect against negative pressure-related complications such as chest discomfort, re-expansion pulmonary edema, or pneumothorax compared with active aspiration. METHODS: This prospective, multicenter, single-blind, randomized controlled trial allocated patients with large free-flowing effusions estimated ≥ 500 mL 1:1 to undergo active aspiration or gravity drainage. Patients rated chest discomfort on 100-mm visual analog scales prior to, during, and following drainage. Thoracentesis was halted at complete evacuation or for persistent chest discomfort, intractable cough, or other complication. The primary outcome was overall procedural chest discomfort scored 5 min following the procedure. Secondary outcomes included measures of discomfort and breathlessness through 48 h postprocedure. RESULTS: A total of 142 patients were randomized to undergo treatment, with 140 in the final analysis. Groups did not differ for the primary outcome (mean visual analog scale score difference, 5.3 mm; 95% CI, -2.4 to 13.0; P = .17). Secondary outcomes of discomfort and dyspnea did not differ between groups. Comparable volumes were drained in both groups, but the procedure duration was significantly longer in the gravity arm (mean difference, 7.4 min; 95% CI, 10.2 to 4.6; P < .001). There were no serious complications. CONCLUSIONS: Thoracentesis via active aspiration and gravity drainage are both safe and result in comparable levels of procedural comfort and dyspnea improvement. Active aspiration requires less total procedural time. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03591952; URL: www.clinicaltrials.gov.


Assuntos
Dor no Peito/epidemiologia , Drenagem/métodos , Dispneia/epidemiologia , Derrame Pleural/cirurgia , Pneumotórax/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Sucção/métodos , Toracentese/métodos , Idoso , Feminino , Gravitação , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Dor Processual/epidemiologia , Edema Pulmonar/epidemiologia , Método Simples-Cego
15.
EGEMS (Wash DC) ; 7(1): 33, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31367650

RESUMO

INTRODUCTION: Health information generated by health care encounters, research enterprises, and public health is increasingly interoperable and shareable across uses and users. This paper examines the US public's willingness to be a part of multi-user health information networks and identifies factors associated with that willingness. METHODS: Using a probability-based sample (n = 890), we examined the univariable and multivariable relationships between willingness to participate in health information networks and demographic factors, trust, altruism, beliefs about the public's ethical obligation to participate in research, privacy, medical deception, and policy and governance using linear regression modeling. RESULTS: Willingness to be a part of a multi-user network that includes health care providers, mental health, social services, research, or quality improvement is low (26 percent-7.4 percent, depending on the user). Using stepwise regression, we identified a model that explained 42.6 percent of the variability in willingness to participate and included nine statistically significant factors associated with the outcome: Trust in the health system, confidence in policy, the belief that people have an obligation to participate in research, the belief that health researchers are accountable for conducting ethical research, the desire to give permission, education, concerns about insurance, privacy, and preference for notification. DISCUSSION: Our results suggest willingness to be a part of multi-user data networks is low, but that attention to governance may increase willingness. Building trust to enable acceptance of multi-use data networks will require a commitment to aligning data access practices with the expectations of the people whose data is being used.

16.
J Neurochem ; 149(3): 362-380, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30664247

RESUMO

The process of locomotion is controlled by fine-tuned dopaminergic neurons in the Substantia Nigra pars-compacta (SNpc) that projects their axons to the dorsal striatum regulating cortical innervations of medium spiny neurons. Dysfunction in dopaminergic neurotransmission within the striatum leads to movement impairments, gaiting defects, and hypo-locomotion. Due to their high polarity and extreme axonal arborization, neurons depend on molecular motor proteins and microtubule-based transport for their normal function. Transport defects have been associated with neurodegeneration since axonopathies, axonal clogging, microtubule destabilization, and lower motor proteins levels were described in the brain of patients with Parkinson's Disease and other neurodegenerative disorders. However, the contribution of specific motor proteins to the regulation of the nigrostriatal network remains unclear. Here, we generated different conditional knockout mice for the kinesin heavy chain 5B subunit (Kif5b) of Kinesin-1 to unravel its contribution to locomotion. Interestingly, mice with neuronal Kif5b deletion showed hypo-locomotion, movement initiation deficits, and coordination impairments. High pressure liquid chromatography determined that dopamine (DA) metabolism is impaired in neuronal Kif5b-KO, while no dopaminergic cell loss was observed. However, the deletion of Kif5b only in dopaminergic neurons is not sufficient to induce locomotor defects. Noteworthy, pharmacological stimulation of DA release together with agonist or antagonist of DA receptors revealed selective D2-dependent movement initiation defects in neuronal Kif5b-KO. Finally, subcellular fractionation from striatum showed that Kif5b deletion reduced the amount of dopamine D2 receptor in synaptic plasma membranes. Together, these results revealed an important role for Kif5b in the modulation of the striatal network that is relevant to the overall locomotor response. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.


Assuntos
Corpo Estriado/metabolismo , Neurônios Dopaminérgicos/metabolismo , Cinesinas/metabolismo , Locomoção/fisiologia , Receptores de Dopamina D2/metabolismo , Animais , Camundongos , Camundongos Knockout
17.
J Cell Sci ; 131(11)2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29724915

RESUMO

Alzheimer disease (AD) pathology includes the accumulation of poly-ubiquitylated (also known as poly-ubiquitinated) proteins and failures in proteasome-dependent degradation. Whereas the distribution of proteasomes and its role in synaptic function have been studied, whether proteasome activity regulates the axonal transport and metabolism of the amyloid precursor protein (APP), remains elusive. By using live imaging in primary hippocampal neurons, we showed that proteasome inhibition rapidly and severely impairs the axonal transport of APP. Fluorescence cross-correlation analyses and membrane internalization blockage experiments showed that plasma membrane APP does not contribute to transport defects. Moreover, by western blotting and double-color APP imaging, we demonstrated that proteasome inhibition precludes APP axonal transport by enhancing its endo-lysosomal delivery, where ß-cleavage is induced. Taken together, we found that proteasomes control the distal transport of APP and can re-distribute Golgi-derived vesicles to the endo-lysosomal pathway. This crosstalk between proteasomes and lysosomes regulates the intracellular APP dynamics, and defects in proteasome activity can be considered a contributing factor that leads to abnormal APP metabolism in AD.This article has an associated First Person interview with the first author of the paper.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Axônios/metabolismo , Lisossomos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Transporte Axonal , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Lisossomos/genética , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Complexo de Endopeptidases do Proteassoma/genética
18.
Sci Rep ; 7(1): 5042, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28698628

RESUMO

The etiology of Parkinson's disease (PD) converges on a common pathogenic pathway of mitochondrial defects in which α-Synuclein (αSyn) is thought to play a role. However, the mechanisms by which αSyn and its disease-associated allelic variants cause mitochondrial dysfunction remain unknown. Here, we analyzed mitochondrial axonal transport and morphology in human-derived neurons overexpressing wild-type (WT) αSyn or the mutated variants A30P or A53T, which are known to have differential lipid affinities. A53T αSyn was enriched in mitochondrial fractions, inducing significant mitochondrial transport defects and fragmentation, while milder defects were elicited by WT and A30P. We found that αSyn-mediated mitochondrial fragmentation was linked to expression levels in WT and A53T variants. Targeted delivery of WT and A53T αSyn to the outer mitochondrial membrane further increased fragmentation, whereas A30P did not. Genomic editing to disrupt the N-terminal domain of αSyn, which is important for membrane association, resulted in mitochondrial elongation without changes in fusion-fission protein levels, suggesting that αSyn plays a direct physiological role in mitochondrial size maintenance. Thus, we demonstrate that the association of αSyn with the mitochondria, which is modulated by protein mutation and dosage, influences mitochondrial transport and morphology, highlighting its relevance in a common pathway impaired in PD.


Assuntos
Homeostase , Mitocôndrias/metabolismo , Neurônios/patologia , Doença de Parkinson/genética , Doença de Parkinson/patologia , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Transporte Axonal , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Membranas Mitocondriais/metabolismo , Proteínas Mutantes/metabolismo , Tamanho das Organelas , Domínios Proteicos , alfa-Sinucleína/química
19.
Eye (Lond) ; 29(8): 1099-110, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26088680

RESUMO

PURPOSE: The utility of in vivo confocal microscopy (IVCM) in the investigation of palpebral conjunctival and corneal inflammation in patients with meibomian gland dysfunction (MGD)-associated refractory dry eye symptoms following gland expression, despite objective clinical improvement. METHODS: A retrospective, observational pilot study was conducted evaluating five patients with MGD-associated refractory dry eye symptoms and three control groups: symptomatic untreated MGD patients (n=3), treatment-responsive MGD patients with improved symptoms (n=3) and asymptomatic healthy normals (n=11). Ocular surface disease index (OSDI) scores, tear break-up time (TBUT), the number of meibomian glands yielding liquid secretion (MGYLS), palpebral conjunctival epithelial and substantia propria immune cell (EIC, SIC), and corneal dendritic cell (DC) densities were measured. RESULTS: Despite clinical improvement (TBUT: 6.4±1.2 s to 10.1±2.1 s, P=0.03; MGYLS: 3.5±0.8 glands to 7.0±1.1 glands, P=0.13) and a normal clinical examination post treatment, MGD patients remained symptomatic. IVCM revealed increased immune cells in the palpebral conjunctiva (refractory MGD EIC=592.6±110.1 cells/mm2 untreated MGD EIC=522.6±104.7 cells/mm2, P=0.69; responsive MGD EIC=194.9±119.4 cells/mm2, P<0.01; normals EIC=123.7±19.2 cells/mm2, P< 0.001), but not the cornea (refractory MGD DC=60.9±28.3 cells/mm2; normals DC=25.9±6.3 cells/mm2; P=0.43). EIC did not correlate with TBUT (Rs=-0.26, P=0.33). OSDI scores correlated with both EIC (Rs=0.76, P<0.001) and TBUT (Rs=-0.69, P<0.01) but not SIC. Intraglandular immune cells were also seen. CONCLUSION: MGD-associated refractory symptoms and the symptom-sign disparity may be explained by clinically non-apparent, active inflammation of the palpebral conjunctiva as detected by IVCM. These patients may benefit from anti-inflammatory therapy.


Assuntos
Edema da Córnea/patologia , Síndromes do Olho Seco/patologia , Glândulas Tarsais/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Edema da Córnea/etiologia , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Lágrimas/metabolismo
20.
Gut ; 64(5): 707-19, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25053715

RESUMO

OBJECTIVE: Gastric cancer (GC) is a deadly malignancy for which new therapeutic strategies are needed. Three transcription factors, KLF5, GATA4 and GATA6, have been previously reported to exhibit genomic amplification in GC. We sought to validate these findings, investigate how these factors function to promote GC, and identify potential treatment strategies for GCs harbouring these amplifications. DESIGN: KLF5, GATA4 and GATA6 copy number and gene expression was examined in multiple GC cohorts. Chromatin immunoprecipitation with DNA sequencing was used to identify KLF5/GATA4/GATA6 genomic binding sites in GC cell lines, and integrated with transcriptomics to highlight direct target genes. Phenotypical assays were conducted to assess the function of these factors in GC cell lines and xenografts in nude mice. RESULTS: KLF5, GATA4 and GATA6 amplifications were confirmed in independent GC cohorts. Although factor amplifications occurred in distinct sets of GCs, they exhibited significant mRNA coexpression in primary GCs, consistent with KLF5/GATA4/GATA6 cross-regulation. Chromatin immunoprecipitation with DNA sequencing revealed a large number of genomic sites co-occupied by KLF5 and GATA4/GATA6, primarily located at gene promoters and exhibiting higher binding strengths. KLF5 physically interacted with GATA factors, supporting KLF5/GATA4/GATA6 cooperative regulation on co-occupied genes. Depletion and overexpression of these factors, singly or in combination, reduced and promoted cancer proliferation, respectively, in vitro and in vivo. Among the KLF5/GATA4/GATA6 direct target genes relevant for cancer development, one target gene, HNF4α, was also required for GC proliferation and could be targeted by the antidiabetic drug metformin, revealing a therapeutic opportunity for KLF5/GATA4/GATA6 amplified GCs. CONCLUSIONS: KLF5/GATA4/GATA6 may promote GC development by engaging in mutual crosstalk, collaborating to maintain a pro-oncogenic transcriptional regulatory network in GC cells.


Assuntos
Fator de Transcrição GATA4/genética , Fator de Transcrição GATA6/genética , Regulação Neoplásica da Expressão Gênica/genética , Fatores de Transcrição Kruppel-Like/genética , Neoplasias Gástricas/genética , Animais , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Fator de Transcrição GATA4/biossíntese , Fator de Transcrição GATA6/biossíntese , Perfilação da Expressão Gênica/métodos , Inativação Gênica , Predisposição Genética para Doença , Xenoenxertos , Humanos , Fatores de Transcrição Kruppel-Like/biossíntese , Camundongos Nus , Transplante de Neoplasias , Oncogenes/genética , Regiões Promotoras Genéticas , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas
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