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1.
bioRxiv ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38712098

RESUMO

Early efforts to understand the human cerebral cortex focused on localization of function, assigning functional roles to specific brain regions. More recent evidence depicts the cortex as a dynamic system, organized into flexible networks with patterns of spatiotemporal activity corresponding to attentional demands. In functional MRI (fMRI), dynamic analysis of such spatiotemporal patterns is highly promising for providing non-invasive biomarkers of neurodegenerative diseases and neural disorders. However, there is no established neurotypical spectrum to interpret the burgeoning literature of dynamic functional connectivity from fMRI across attentional states. In the present study, we apply dynamic analysis of network-scale spatiotemporal patterns in a range of fMRI datasets across numerous tasks including a left-right moving dot task, visual working memory tasks, congruence tasks, multiple resting state datasets, mindfulness meditators, and subjects watching TV. We find that cortical networks show shifts in dynamic functional connectivity across a spectrum that tracks the level of external to internal attention demanded by these tasks. Dynamics of networks often grouped into a single task positive network show divergent responses along this axis of attention, consistent with evidence that definitions of a single task positive network are misleading. Additionally, somatosensory and visual networks exhibit strong phase shifting along this spectrum of attention. Results were robust on a group and individual level, further establishing network dynamics as a potential individual biomarker. To our knowledge, this represents the first study of its kind to generate a spectrum of dynamic network relationships across such an axis of attention.

2.
bioRxiv ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38645080

RESUMO

The intrinsic dynamics of human brain activity display a recurring pattern of anti-correlated activity between the default mode network (DMN), associated with internal processing and mentation, and task positive regions, associated with externally directed attention. In human functional magnetic resonance imaging (fMRI) data, this anti-correlated pattern is detectable on the infraslow timescale (<0.1 Hz) as a quasi-periodic pattern (QPP). While the DMN is implicated in creativity and musicality in traditional time-averaged functional connectivity studies, no one has yet explored how creative training may alter dynamic spatiotemporal patterns involving the DMN such as QPPs. In the present study, we compare the outputs of two QPP detection approaches, sliding window algorithm and complex principal components analysis (cPCA). We apply both methods to an existing dataset of musicians captured with resting state fMRI, grouped as either classical, improvisational, or minimally trained non-musicians. The original time-averaged functional connectivity (FC) analysis of this dataset used improvisation as a proxy for creative thinking and found that the DMN and visual networks (VIS) display higher connectivity in improvisational musicians. We expand upon this dataset's original study and find that QPP analysis detects convergent results at the group level with both methods. In improvisational musicians, dynamic functional correlation in the group-averaged QPP was found to be increased between the DMN-VIS and DMN-FPN for both the QPP algorithm and complex principal components analysis (cPCA) methods. Additionally, we found an unexpected increase in FC in the group-averaged QPP between the dorsal attention network and amygdala in improvisational musicians; this result was not reported in the original seed-based study of this dataset. The current study represents a novel application of two dynamic FC detection methods with results that replicate and expand upon previous seed-based FC findings. The results show the robustness of both the QPP phenomenon and its detection methods. This study also demonstrates the value of dynamic FC methods in reproducing seed-based findings and their promise in detecting group-wise or individual differences that may be missed by traditional seed-based resting state fMRI studies.

4.
JGH Open ; 7(7): 509-515, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37496818

RESUMO

Background and Aim: Overt obscure gastrointestinal bleeding (OOGIB) is defined as continued bleeding with unknown source despite esophagogastroduodenoscopy (EGD) and colonoscopy evaluation. Small bowel evaluation through video capsule endoscopy (VCE) or double balloon enteroscopy (DBE) is often warranted. We studied the timing of DBE in hospitalized OOGIB patients regarding diagnostic yield, therapeutic yield, and GI rebleeding. Methods: We performed a retrospective review of DBEs performed at a tertiary medical center between November 2012 and December 2020. The inclusion criterion was first admission for OOGIB undergoing DBE. Those without previous EGD or colonoscopy were excluded. Patients were stratified into two groups: DBE performed within 72 h of OOGIB (emergent) and beyond 72 h of OOGIB (nonemergent). Propensity score matching was used to adjust for the difference in patients in the two groups. Logistic regression analysis was used to assess factors associated with diagnostic and therapeutic yield. Kaplan-Meir survival curve showed GI bleed-free survival following initial bleed and was compared using the log rank test. Results: A total of 154 patients met the inclusion criterion, of which 62 had emergent DBE and 92 had nonemergent DBE. The propensity-score-matched sample consisted of 112 patients, with 56 patients each in the emergent and nonemergent groups. Univariate and multivariable logistic regression analysis showed a significant association between VCE and emergent DBE and diagnostic and therapeutic yield (P < 0.05). Emergent DBE patients had increased GI bleed-free survival compared to those in the nonemergent group (P = 0.009). Conclusion: Our data demonstrate that emergent DBE during inpatient OOGIB can impact the overall diagnostic yield, therapeutic yield, and GI rebleeding post DBE.

5.
Endosc Int Open ; 10(9): E1282-E1290, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36118633

RESUMO

Background and study aims Obesity prevalence continues to rise in the United States with Roux-en-Y gastric bypass (RYGB) surgery being one of the most common bariatric procedures. With this trend, more patients with altered upper gastrointestinal (UGI) anatomy have required endoscopic intervention including direct percutaneous endoscopic jejunostomy (DPEJ) placement. We aimed to assess the safety and success rates of DPEJ in RYGB patients. Patients and methods All patients at a tertiary care referral center who underwent DPEJ during an 8-year period were queried from a prospectively maintained registry of all enteroscopy procedures. Duplicate cases and altered upper UGI anatomy subtypes other than RYGB were excluded. The final cohort consisted of two groups: RYGB vs native anatomy (NA). Demographic, procedural, readmission, follow-up, and complication data were recorded. Comparative analysis was performed. Results Seventy-two patients were included where 28 had RYGB and 44 had NA. Both groups had similar baseline and pre-procedure data. Procedure success rate was 89 % in RYGB patients and 98 % in NA patients ( P  = 0.13). There were no intraprocedural complications. Early and late postprocedural complication rates were similar between the groups (both 4 % vs 7 %). Average follow-up times in the RYGB and NA groups were 12.97 ±â€Š9.35 and 13.44 ±â€Š9.21 months, respectively. Although readmission rates at 1 and 6 months were higher in the NA versus the RYGB group (21 % vs 7 % and 25 % vs 15 %), these differences were not significant. Conclusions DPEJ can be successful and safely placed in RYGB patients with no significant difference in procedure success, complication, or readmission rates when compared to control.

6.
Respir Care ; 66(5): 822-828, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33531358

RESUMO

BACKGROUND: Lean Six Sigma processes are used in health care systems to increase safety and efficiency. Daily huddles, one tool of the Lean Six Sigma process, have been used to increase patient safety, facilitate efficiency in problem solving, promote optimal patient outcomes, and reduce poor communication. Huddle utilization by respiratory care departments has not been previously reported. We describe our process of implementing daily huddles and the impact on departmental problem solving. METHOD: A descriptive study of a quality improvement intervention and a retrospective study of prospectively collected data were performed. The respiratory care department was trained in the utilization of a daily huddle process to resolve issues and identify process improvement opportunities. Huddles were performed at the beginning of each shift. Process improvement opportunities were raised by the respiratory therapy staff using the following categories: Safety/Service, Methods, Equipment, Supplies, and Associates. Opportunities were placed within 3 categories; quick hits (resolution in 1-3 d), complex problems (resolution in 3-7 d), and projects (resolution in > 7 d). All opportunities included a problem statement, an immediate countermeasure, a problem leader, and a due date. Items requiring interdisciplinary support were escalated to the organizational patient care services huddle. We evaluated the number and nature of process improvement opportunities raised in huddles from January 1 through December 31, 2018, to better understand the impact of daily huddles. RESULTS: A total of 366 process improvement opportunities were raised during huddles. Of those, 245 (67%) were quick hits, 77 (21%) were complex, and 44 (12%) were projects. Resolution of 174 (47.5%) opportunities was completed using only the resources of the respiratory care department, and 157 (43%) were resolved with additional interdisciplinary involvement. A small portion 35 (9.5%) of opportunities required escalation to the organizational multidisciplinary huddle for resolution. All process improvement opportunities were resolved at the end of the study period (mean ± SD of 30.5 ± 7.7 per month). CONCLUSIONS: Twice-daily huddles implemented by our respiratory care department allowed for identification and timely resolution of process improvement opportunities.


Assuntos
Resolução de Problemas , Melhoria de Qualidade , Atenção à Saúde , Humanos , Terapia Respiratória , Estudos Retrospectivos
7.
Dev Biol ; 453(1): 86-104, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31136738

RESUMO

Changes in chromatin accessibility regulate the expression of multiple genes by controlling transcription factor access to key gene regulatory sequences. Here, we sought to establish a potential function for altered chromatin accessibility in control of key gene expression events during lens cell differentiation by establishing genome-wide chromatin accessibility maps specific for four distinct stages of lens cell differentiation and correlating specific changes in chromatin accessibility with genome-wide changes in gene expression. ATAC sequencing was employed to generate chromatin accessibility profiles that were correlated with the expression profiles of over 10,000 lens genes obtained by high-throughput RNA sequencing at the same stages of lens cell differentiation. Approximately 90,000 regions of the lens genome exhibited distinct changes in chromatin accessibility at one or more stages of lens differentiation. Over 1000 genes exhibited high Pearson correlation coefficients (r â€‹> â€‹0.7) between altered expression levels at specific stages of lens cell differentiation and changes in chromatin accessibility in potential promoter (-7.5kbp/+2.5kbp of the transcriptional start site) and/or other potential cis-regulatory regions ( ±10 â€‹kb of the gene body). Analysis of these regions identified consensus binding sequences for multiple transcription factors including members of the TEAD, FOX, and NFAT families of transcription factors as well as HIF1a, RBPJ and IRF1. Functional mapping of genes with high correlations between altered chromatin accessibility and differentiation state-specific gene expression changes identified multiple families of proteins whose expression could be regulated through changes in chromatin accessibility including those governing lens structure (BFSP1,BFSP2), gene expression (Pax-6, Sox 2), translation (TDRD7), cell-cell communication (GJA1), autophagy (FYCO1), signal transduction (SMAD3, EPHA2), and lens transparency (CRYBB1, CRYBA4). These data provide a novel relationship between altered chromatin accessibility and lens differentiation and they identify a wide-variety of lens genes and functions that could be regulated through altered chromatin accessibility. The data also point to a large number of potential DNA regulatory sequences and transcription factors whose functional analysis is likely to provide insight into novel regulatory mechanisms governing the lens differentiation program.


Assuntos
Diferenciação Celular/genética , Cromatina/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Cristalino/citologia , Animais , Sequência de Bases , Sítios de Ligação , Biomarcadores/metabolismo , Galinhas/genética , Sequência Consenso/genética , DNA/metabolismo , Genoma , Cristalino/metabolismo , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo
8.
J Exp Child Psychol ; 107(4): 479-93, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20659735

RESUMO

This research examined whether the impact of overheard rumors on children's memory for their experiences varies as a function of social processes. The results of two experiments revealed that the very same errant rumor had different consequences for children's recollections depending on the degree and type of social interactions they had with peers after exposure to the rumor. In both experiments, 3- to 5-year-olds overheard a false rumor about a recently experienced event and then were interviewed about the event 1 week later. In Experiment 1, children were more likely to report experiencing rumored-but-nonoccurring information if they were allowed to interact naturally with peers following exposure to the rumor than if they were prevented from peer exchange. In Experiment 2, exposure to the rumor induced greater memory contamination if it was planted among familiar peers than if it was encountered among strangers.


Assuntos
Comportamento Infantil/fisiologia , Comportamento Infantil/psicologia , Enganação , Rememoração Mental/fisiologia , Comportamento Social , Sugestão , Pré-Escolar , Feminino , Humanos , Relações Interpessoais , Masculino , New England , Grupo Associado
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