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1.
Am J Hum Genet ; 111(2): 259-279, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38232730

RESUMO

Tauopathies are a group of neurodegenerative diseases defined by abnormal aggregates of tau, a microtubule-associated protein encoded by MAPT. MAPT expression is near absent in neural progenitor cells (NPCs) and increases during differentiation. This temporally dynamic expression pattern suggests that MAPT expression could be controlled by transcription factors and cis-regulatory elements specific to differentiated cell types. Given the relevance of MAPT expression to neurodegeneration pathogenesis, identification of such elements is relevant to understanding disease risk and pathogenesis. Here, we performed chromatin conformation assays (HiC & Capture-C), single-nucleus multiomics (RNA-seq+ATAC-seq), bulk ATAC-seq, and ChIP-seq for H3K27ac and CTCF in NPCs and differentiated neurons to nominate candidate cis-regulatory elements (cCREs). We assayed these cCREs using luciferase assays and CRISPR interference (CRISPRi) experiments to measure their effects on MAPT expression. Finally, we integrated cCRE annotations into an analysis of genetic variation in neurodegeneration-affected individuals and control subjects. We identified both proximal and distal regulatory elements for MAPT and confirmed the regulatory function for several regions, including three regions centromeric to MAPT beyond the H1/H2 haplotype inversion breakpoint. We also found that rare and predicted damaging genetic variation in nominated CREs was nominally depleted in dementia-affected individuals relative to control subjects, consistent with the hypothesis that variants that disrupt MAPT enhancer activity, and thereby reduced MAPT expression, may be protective against neurodegenerative disease. Overall, this study provides compelling evidence for pursuing detailed knowledge of CREs for genes of interest to permit better understanding of disease risk.


Assuntos
Doenças Neurodegenerativas , Proteínas tau , Humanos , Cromatina/genética , Haplótipos , Doenças Neurodegenerativas/genética , Neurônios , Sequências Reguladoras de Ácido Nucleico/genética , Proteínas tau/genética
2.
bioRxiv ; 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37090552

RESUMO

Background: Tauopathies are a group of neurodegenerative diseases driven by abnormal aggregates of tau, a microtubule associated protein encoded by the MAPT gene. MAPT expression is absent in neural progenitor cells (NPCs) and increases during differentiation. This temporally dynamic expression pattern suggests that MAPT expression is controlled by transcription factors and cis-regulatory elements specific to differentiated cell types. Given the relevance of MAPT expression to neurodegeneration pathogenesis, identification of such elements is relevant to understanding genetic risk factors. Methods: We performed HiC, chromatin conformation capture (Capture-C), single-nucleus multiomics (RNA-seq+ATAC-seq), bulk ATAC-seq, and ChIP-seq for H3K27Ac and CTCF in NPCs and neurons differentiated from human iPSC cultures. We nominated candidate cis-regulatory elements (cCREs) for MAPT in human NPCs, differentiated neurons, and pure cultures of inhibitory and excitatory neurons. We then assayed these cCREs using luciferase assays and CRISPR interference (CRISPRi) experiments to measure their effects on MAPT expression. Finally, we integrated cCRE annotations into an analysis of genetic variation in AD cases and controls. Results: Using orthogonal genomics approaches, we nominated 94 cCREs for MAPT, including the identification of cCREs specifically active in differentiated neurons. Eleven regions enhanced reporter gene transcription in luciferase assays. Using CRISPRi, 5 of the 94 regions tested were identified as necessary for MAPT expression as measured by RT-qPCR and RNA-seq. Rare and predicted damaging genetic variation in both nominated and confirmed CREs was depleted in AD cases relative to controls (OR = 0.40, p = 0.004), consistent with the hypothesis that variants that disrupt MAPT enhancer activity, and thereby reduce MAPT expression, may be protective against neurodegenerative disease. Conclusions: We identified both proximal and distal regulatory elements for MAPT and confirmed the regulatory function for several regions, including three regions centromeric to MAPT beyond the well-described H1/H2 haplotype inversion breakpoint. This study provides compelling evidence for pursuing detailed knowledge of CREs for genes of interest to permit better understanding of disease risk.

3.
Cell Genom ; 3(3): 100263, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36950385

RESUMO

Cell type-specific transcriptional differences between brain tissues from donors with Alzheimer's disease (AD) and unaffected controls have been well documented, but few studies have rigorously interrogated the regulatory mechanisms responsible for these alterations. We performed single nucleus multiomics (snRNA-seq plus snATAC-seq) on 105,332 nuclei isolated from cortical tissues from 7 AD and 8 unaffected donors to identify candidate cis-regulatory elements (CREs) involved in AD-associated transcriptional changes. We detected 319,861 significant correlations, or links, between gene expression and cell type-specific transposase accessible regions enriched for active CREs. Among these, 40,831 were unique to AD tissues. Validation experiments confirmed the activity of many regions, including several candidate regulators of APP expression. We identified ZEB1 and MAFB as candidate transcription factors playing important roles in AD-specific gene regulation in neurons and microglia, respectively. Microglia links were globally enriched for heritability of AD risk and previously identified active regulatory regions.

4.
Sci Data ; 8(1): 299, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815420

RESUMO

This paper provides an open dataset of measured energy use, solar energy production, and building air leakage data from a 328 m2 (3,531 ft2) all-electric, zero energy commercial building in Virginia, USA. Over two years of energy use data were collected at 1-hour intervals using circuit-level energy monitors. Over six years of solar energy production data were measured at 1-hour resolution by 56 microinverters (presented as daily and monthly data in this dataset). The building air leakage data was measured post-construction per ASTM-E779 Standard Test Method for Determining Air Leakage Rate by Fan Pressurization and the United States Army Corps (USACE) Building Enclosure Testing procedure; both pressurization and depressurization results are provided. The architectural and engineering (AE) documents are provided to aid researchers and practitioners in reliable modeling of building performance. The paper describes the data collection methods, cleaning, and convergence with weather data. This dataset can be employed to predict, benchmark, and calibrate operational outcomes in zero energy commercial buildings.

6.
Neurourol Urodyn ; 37(8): 2425-2433, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29777585

RESUMO

AIMS: Chronic ischemia is a recognized factor in the pathophysiology of underactive bladder (UAB). Although relative ischemia (ie, low blood flow) is known to occur during filling, little is known regarding the pathophysiology that leads to UAB. Therefore, we developed an ex vivo functional porcine model to investigate the role of transient ischemia and whether autoregulation, a mechanism that maintains tissue oxygenation in certain vital organs, also exists in the bladder. METHODS: Using bladders from slaughtered pigs, we prepared an isolated perfused model where we studied the effects of bladder perfusion flow rate on perfusion pressure and tissue oxygenation during the filling phase. Bladders were perfused at an initial flow rate of 20 mL/min and then clamped in a sequentially decreasing stepwise manner down to no flow and back to the initial flow rate. RESULTS: We found a linear relationship between flow rate and perfusion pressure until the flow rate decreased below 5 mL/min at which point the vascular resistance decreased; however, tissue pO2 remained stable after an initial decline. CONCLUSIONS: These findings suggest that there may be an intrinsic autoregulatory mechanism in the bladder that allows it to undergo cyclic episodes of relative ischemia during its normal function. Factors that overcome this mechanism such as complete or chronic ischemia may be critical in the progression to detrusor underactivity and thereby highlight the importance of intervention during the early phases of this disease process.


Assuntos
Vasos Sanguíneos/fisiologia , Bexiga Urinária/irrigação sanguínea , Bexiga Urinária/fisiologia , Animais , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Feminino , Homeostase , Técnicas In Vitro , Isquemia/fisiopatologia , Modelos Biológicos , Consumo de Oxigênio/fisiologia , Perfusão , Pressão , Suínos , Bexiga Inativa/fisiopatologia , Resistência Vascular/fisiologia
7.
Acad Med ; 93(7): 1035-1041, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29166350

RESUMO

PURPOSE: To identify common and overlapping themes among the interpersonal and communication skills (ICS), practice-based learning and improvement (PBLI), professionalism (PROF), and systems-based practice (SBP) milestones of the transitional year and 26 specialties. METHOD: In May 2017, milestones were accessed from the Accreditation Council for Graduate Medical Education specialties website. A thematic analysis of the ICS, PBLI, PROF, and SBP milestones was performed to determine unique and common themes across these competencies and across specialties. Keywords from the common program requirements were initially applied as codes to the milestones. Codes were then grouped into common themes. RESULTS: Twenty-two themes were identified: 15 (68%) were unique to a given competency (3 related to ICS, 4 related to PBLI, 5 related to PROF, and 3 related to SBP), and 7 (32%) appeared in the milestones of more than one core competency. Eleven themes (50%) were used by 20 or more specialties, and 6 themes (27%) by 10 or fewer specialties. No theme was present across all specialties. CONCLUSIONS: The ICS, PBLI, PROF, and SBP milestones contain multiple themes with areas of overlap among these four competencies and substantial variability across specialties. This variability may create differential expectations of residents across specialties, complicate faculty development, and make sharing assessment tools difficult. The thematic analysis provides important insights into how individual specialties interpret and operationalize the ICS, PBLI, PROF, and SBP competency domains and can inform future revisions of milestones to enable harmonization and shared understanding of these competencies across specialties where appropriate.


Assuntos
Acreditação/normas , Educação Médica/métodos , Acreditação/métodos , Educação Baseada em Competências/métodos , Educação de Pós-Graduação em Medicina/métodos , Educação de Pós-Graduação em Medicina/tendências , Humanos , Profissionalismo/normas , Habilidades Sociais , Análise de Sistemas
8.
Urology ; 61(1): 179-83, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12559292

RESUMO

OBJECTIVES: To report the outcome and morbidity data for patients treated with post-prostatectomy radiotherapy (PPRT) in a multicenter collaboration. METHODS: The case records of all patients treated with PPRT from 1996 to 1998 were reviewed. Survival was calculated using Kaplan-Meier methods. Potential prognostic factors were evaluated using the Cox proportional hazards regression model. Prostate-specific antigen (PSA) remission was defined as a PSA level of 0.2 ng/mL or less. Acute and late morbidities were documented. RESULTS: We reviewed the data of 115 patients, with a median follow-up from the start of PPRT of 28.7 months. Patients were treated with adjuvant intent (n = 23), for local recurrence (n = 27), or for a detectable PSA level (n = 65). The overall and cause-specific survival rate at 5 years was 73.7% and 81.4%, respectively. The biochemical disease-free survival rate was 69.6% at 2 years and 50% at 5 years. Factors predicting for subsequent relapse on multivariate analysis were pre-PPRT PSA (P = 0.013) and post-PPRT nadir (P <0.0001). Patients with a PSA greater than 1 ng/mL fared significantly worse than those with lower levels (P <0.0001). For patients with a pretreatment PSA of less than 1 ng/mL and an operative Gleason score of 7 or less, the 5-year projected biochemical disease-free survival rate was 71%. One case of grade 3 late proctitis was recorded, and 4 patients had continued grade 3 late urinary incontinence. CONCLUSIONS: Early use of PPRT is effective and well tolerated in patients at risk of, or with proven, local recurrence.


Assuntos
Recidiva Local de Neoplasia/radioterapia , Complicações Pós-Operatórias/radioterapia , Prostatectomia , Neoplasias da Próstata/diagnóstico , Idoso , Austrália , Intervalo Livre de Doença , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Modelos de Riscos Proporcionais , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/radioterapia , Resultado do Tratamento
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