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1.
Biochem Biophys Res Commun ; 534: 1059-1063, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33121681

RESUMO

DNA target search is a key step in cellular transactions that access genomic information. How DNA binding proteins combine 3D diffusion, sliding and hopping into an overall search strategy remains poorly understood. Here we report the use of a single molecule DNA tethering method to characterize the target search kinetics of the type II restriction endonuclease NdeI. The measured search rate depends strongly on DNA length as well as salt concentration. Using roadblocks, we show that there are significant changes in the DNA sliding length over the salt concentrations in our study. To explain our results, we propose a model including cycles of 3D and 1D search in which salt concentration modulates the strategy by varying the length of DNA probed per 1D scan. At low salt NdeI makes a single non-specific encounter with DNA followed by an effective and complete 1D scan. At higher salt, NdeI must execute multiple cycles of target search due to the reduced efficacy of 1D search.


Assuntos
DNA/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Cloreto de Sódio/metabolismo , DNA/química , Clivagem do DNA , Difusão , Desenho de Equipamento , Ácidos Nucleicos Imobilizados/química , Ácidos Nucleicos Imobilizados/metabolismo , Cinética , Técnicas Analíticas Microfluídicas/instrumentação
2.
Am J Hosp Palliat Care ; : 10499091241247841, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627935

RESUMO

BACKGROUND: Terminally ill patients benefit from earlier engagement in palliative care. However, this does not always occur. This project assessed if an already available risk score, the Care Assessment Needs (CAN) score, would be able to identify patients at greatest risk for mortality within 30 days of hospital admission within the Veterans Health Administration (VHA). METHODS: The cohort of this retrospective analysis included all VA acute are patients over 18 years of age with a recent CAN score. The CAN score is an automatically calculated VA risk score that was repurposed to determine if it could predict risk of mortality after acute care admission. Univariate logistic regression was performed to obtain the probability of mortality within 30 days of admission, based on their CAN score. RESULTS: 298,467 patient records were assessed from January 1, 2019, to December 31, 2019. There was 6% mortality after 30 days of admissions, and 17% mortality within 1-year post-admission. Mean CAN score was 65 (SD: 29). On average, each incremental increase in the CAN score increased the probability of mortality by 7%. Patients with a CAN score of 90 had a 10% probability of 30-day post-admission mortality. CONCLUSION: A readily available risk score, automatically calculated from EHR data, was able to identify patients at high risk for 30-day mortality in the acute care setting. Next steps will be to assess how the CAN score can be utilized to in improve end of life care for high-risk hospitalized Veterans.

3.
PLoS One ; 19(9): e0302612, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39288150

RESUMO

INTRODUCTION: COVID-19 triggers prothrombotic and proinflammatory changes, with thrombotic disease prevalent in up to 30% SARS-CoV-2 infected patients. Early work suggests that aspirin could prevent COVID-19 related thromboembolic disorders in some studies but not others. This study leverages data from the largest integrated healthcare system in the United States to better understand this association. Our objective was to evaluate the incidence and risk of COVID-19 associated acute thromboembolic disorders and the potential impact of aspirin. METHODS: This retrospective, observational study utilized national electronic health record data from the Veterans Health Administration. 334,374 Veterans who tested positive for COVID-19 from March 2, 2020, to June 13, 2022, were included, 81,830 of whom had preexisting aspirin prescription prior to their COVID-19 diagnosis. Patients with and without aspirin prescriptions were matched and the odds of post-COVID acute thromboembolic disorders were assessed. RESULTS: 10.1% of Veterans had a documented thromboembolic disorder within 12 months following their COVID-19 diagnosis. Those with specific comorbidities were at greatest risk. Preexisting aspirin prescription was associated with a significant decrease risk of post-COVID-19 thromboembolic disorders, including pulmonary embolism (OR [95% CI]: 0.69 [0.65, 0.74]) and deep vein thrombosis (OR [95% CI]: 0.76 [0.69, 0.83], but an increased risk of acute arterial diseases, including ischemic stroke (OR [95% CI]: 1.54 [1.46, 1.60]) and acute ischemic heart disease (1.33 [1.26, 1.39]). CONCLUSIONS: Findings demonstrated that preexisting aspirin prescription prior to COVID-19 diagnosis was associated with significantly decreased risk of venous thromboembolism and pulmonary embolism but increased risk of acute arterial disease. The risk of arterial disease may be associated with increased COVID-19 prothrombotic effects superimposed on preexisting chronic cardiovascular disease for which aspirin was already prescribed. Prospective clinical trials may help to further assess the efficacy of aspirin use prior to COVID-19 diagnosis for the prevention of post-COVID-19 thromboembolic disorders.


Assuntos
Aspirina , COVID-19 , Tromboembolia , United States Department of Veterans Affairs , Veteranos , Humanos , Aspirina/uso terapêutico , Estados Unidos/epidemiologia , COVID-19/epidemiologia , COVID-19/complicações , COVID-19/prevenção & controle , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Incidência , Tromboembolia/epidemiologia , Tromboembolia/prevenção & controle , Tromboembolia/etiologia , Tromboembolia/tratamento farmacológico , SARS-CoV-2 , Fatores de Risco , Idoso de 80 Anos ou mais
4.
Health Serv Res ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056425

RESUMO

OBJECTIVE: To develop, deploy, and evaluate a national, electronic health record (EHR)-based dashboard to support safe prescribing of biologic and targeted synthetic disease-modifying agents (b/tsDMARDs) in the United States Veterans Affairs Healthcare System (VA). DATA SOURCES AND STUDY SETTING: We extracted and displayed hepatitis B (HBV), hepatitis C (HCV), and tuberculosis (TB) screening data from the EHR for users of b/tsDMARDs using PowerBI (Microsoft) and deployed the dashboard to VA facilities across the United States in 2022; we observed facilities for 44 weeks post-deployment. STUDY DESIGN: We examined the association between dashboard engagement by healthcare personnel and the percentage of patients with all screenings complete (HBV, HCV, and TB) at the facility level using an interrupted time series. Based on frequency of sessions, facilities were grouped into high- and low/none-engagement categories. We modeled changes in complete screening pre- and post-deployment of the dashboard. DATA COLLECTION METHODS: All VA facilities were eligible for inclusion; excluded facilities participated in design of the dashboard or had <20 patients receiving b/tsDMARDs. Session counts from facility personnel were captured using PowerBI audit log data. Outcomes were assessed weekly based on EHR data extracted via the dashboard itself. PRINCIPAL FINDINGS: Totally 117 facilities (serving a total of 41,224 Veterans prescribed b/tsDMARDs) were included. Before dashboard deployment, across all facilities, 61.5% of patients had all screenings complete, which improved to 66.3% over the course of the study period. The largest improvement (15 percentage points, 60.3%-75.3%) occurred among facilities with high engagement (post-intervention difference in outcome between high and low/none-engagement groups was 0.17 percentage points (pp) per week, 95% confidence interval (0.04 pp, 0.30 pp); p = 0.01). CONCLUSIONS: We observed significant improvements in screening for latent infections among facilities with high engagement with the dashboard, compared with those with fewer sessions.

5.
medRxiv ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38978655

RESUMO

Postsurgical falls have significant patient and societal implications but remain challenging to identify and track. Detecting postsurgical falls is crucial to improve patient care for older adults and reduce healthcare costs. Large language models (LLMs) offer a promising solution for reliable and automated fall detection using unstructured data in clinical notes. We tested several LLM prompting approaches to postsurgical fall detection in two different healthcare systems with three open-source LLMs. The Mixtral-8×7B zero-shot had the best performance at Stanford Health Care (PPV = 0.81, recall = 0.67) and the Veterans Health Administration (PPV = 0.93, recall = 0.94). These results demonstrate that LLMs can detect falls with little to no guidance and lay groundwork for applications of LLMs in fall prediction and prevention across many different settings.

6.
Arthritis Care Res (Hoboken) ; 76(2): 274-287, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37643903

RESUMO

OBJECTIVE: Approximately one third of individuals worldwide have not received a COVID-19 vaccine. Although studies have investigated risk factors linked to severe COVID-19 among unvaccinated people with rheumatic diseases (RDs), we know less about whether these factors changed as the pandemic progressed. We aimed to identify risk factors associated with severe COVID-19 in unvaccinated individuals in different pandemic epochs corresponding to major variants of concern. METHODS: Patients with RDs and COVID-19 were entered into the COVID-19 Global Rheumatology Alliance Registry between March 2020 and June 2022. An ordinal logistic regression model (not hospitalized, hospitalized, and death) was used with date of COVID-19 diagnosis, age, sex, race and/or ethnicity, comorbidities, RD activity, medications, and the human development index (HDI) as covariates. The main analysis included all unvaccinated patients across COVID-19 pandemic epochs; subanalyses stratified patients according to RD types. RESULTS: Among 19,256 unvaccinated people with RDs and COVID-19, those who were older, male, had more comorbidities, used glucocorticoids, had higher disease activity, or lived in lower HDI regions had worse outcomes across epochs. For those with rheumatoid arthritis, sulfasalazine and B-cell-depleting therapy were associated with worse outcomes, and tumor necrosis factor inhibitors were associated with improved outcomes. In those with connective tissue disease or vasculitis, B-cell-depleting therapy was associated with worse outcomes. CONCLUSION: Risk factors for severe COVID-19 outcomes were similar throughout pandemic epochs in unvaccinated people with RDs. Ongoing efforts, including vaccination, are needed to reduce COVID-19 severity in this population, particularly in those with medical and social vulnerabilities identified in this study.


Assuntos
COVID-19 , Doenças Reumáticas , Reumatologia , Humanos , Masculino , Pandemias , Vacinas contra COVID-19/uso terapêutico , Teste para COVID-19 , COVID-19/epidemiologia , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/epidemiologia , Fatores de Risco , Sistema de Registros
7.
Neuro Oncol ; 25(9): 1617-1630, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36806881

RESUMO

BACKGROUND: Neurofibromatosis 2 (NF2) is an inherited disorder caused by bi-allelic inactivation of the NF2 tumor suppressor gene. NF2-associated tumors, including schwannoma and meningioma, are resistant to chemotherapy, often recurring despite surgery and/or radiation, and have generally shown cytostatic response to signal transduction pathway inhibitors, highlighting the need for improved cytotoxic therapies. METHODS: Leveraging data from our previous high-throughput drug screening in NF2 preclinical models, we identified a class of compounds targeting the ubiquitin-proteasome pathway (UPP), and undertook studies using candidate UPP inhibitors, ixazomib/MLN9708, pevonedistat/MLN4924, and TAK-243/MLN7243. Employing human primary and immortalized meningioma (MN) cell lines, CRISPR-modified Schwann cells (SCs), and mouse Nf2-/- SCs, we performed dose response testing, flow cytometry-based Annexin V and cell cycle analyses, and RNA-sequencing to identify potential underlying mechanisms of apoptosis. In vivo efficacy was also assessed in orthotopic NF2-deficient meningioma and schwannoma tumor models. RESULTS: Testing of three UPP inhibitors demonstrated potent reduction in cell viability and induction of apoptosis for ixazomib or TAK-243, but not pevonedistat. In vitro analyses revealed that ixazomib or TAK-243 downregulates expression of c-KIT and PDGFRα, as well as the E3 ubiquitin ligase SKP2 while upregulating genes associated with endoplasmic reticulum stress-mediated activation of the unfolded protein response (UPR). In vivo treatment of mouse models revealed delayed tumor growth, suggesting a therapeutic potential. CONCLUSIONS: This study demonstrates the efficacy of proteasomal pathway inhibitors in meningioma and schwannoma preclinical models and lays the groundwork for use of these drugs as a promising novel treatment strategy for NF2 patients.


Assuntos
Neoplasias Meníngeas , Meningioma , Neurilemoma , Neurofibromatose 2 , Animais , Humanos , Camundongos , Neoplasias Meníngeas/genética , Meningioma/genética , Neurilemoma/tratamento farmacológico , Neurilemoma/genética , Neurofibromatose 2/tratamento farmacológico , Neurofibromina 2/genética
8.
Oncogene ; 41(13): 1974-1985, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35173307

RESUMO

Epithelial ovarian cancer is the most lethal gynecologic malignancy and one of the most common causes of cancer mortality among women worldwide. Ubiquitin-Specific Peptidase 13 (USP13) gene copy is strongly amplified in human epithelial ovarian cancer, and high USP13 expression is correlated with poor survival outcomes. Yet, its pathological contribution to ovarian tumorigenesis remains unknown. We crossed a conditional Usp13 overexpressing knock-in mouse with a conditional knockout of Trp53 and Pten mouse and generated a novel ovarian cancer genetically engineered mouse model (GEMM), which closely recapitulates the genetic changes driving ovarian cancer in humans. Overexpression of USP13 with deletion of Trp53 and Pten in murine ovarian surface epithelium accelerated ovarian tumorigenesis and led to decreased survival in mice. Notably, USP13 greatly enhanced peritoneal metastasis of ovarian tumors with frequent development of hemorrhagic ascites. The primary and metastatic tumors exhibited morphology and clinical behavior similar to human high-grade serous ovarian cancer. Co-inhibition of USP13 and AKT significantly decreased the viability of the primary murine ovarian cancer cells isolated from the GEMM. USP13 also increased the tumorigenic and metastatic abilities of primary murine ovarian cancer cells in a syngeneic mouse study. These findings suggest a critical role of USP13 in ovarian cancer development and reveal USP13 as a potential therapeutic target for ovarian cancer.


Assuntos
Neoplasias Ovarianas , Proteases Específicas de Ubiquitina , Animais , Carcinogênese/genética , Carcinoma Epitelial do Ovário , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Neoplasias Ovarianas/patologia , Proteases Específicas de Ubiquitina/genética
9.
Brain Struct Funct ; 226(5): 1453-1466, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33718987

RESUMO

The dorsolateral prefrontal cortex (DLPFC) is activated when bilinguals switch between languages. Language switching can also elicit the N2 event-related potential (ERP). This ERP component appears to capture the cognitive control processes related to conflict monitoring, response selection and response inhibition. In the present study, continuous theta-burst stimulation (cTBS) was used to examine the role of the left DLPFC in bilingual language switching, using a picture-naming task. Participants in the study were 17 Afrikaans-English bilinguals. The picture-naming task consisted of non-switch and switch trials. On non-switch trials, participants named two consecutive pictures in the same language. On switch trials, participants named consecutive pictures in different languages (e.g., Afrikaans and then English). The participants completed three testing sessions. In each session, participants received either cTBS to the left DLPFC or the vertex, or sham stimulation, and then completed the picture-naming task. The results showed that following DLPFC stimulation, the N2 ERP was attenuated on switch trials compared to non-switch trials. Vertex or sham stimulation did not modulate the N2 ERP. cTBS did not affect language switching at the behavioural level. These results provide support for the role of the left DLPFC in the cognitive control processes underlying bilingual language switching. Furthermore, the study demonstrates that these processes can be modulated via non-invasive brain stimulation and the effects detected at the neural level.


Assuntos
Idioma , Córtex Pré-Frontal Dorsolateral , Potenciais Evocados , Humanos , Multilinguismo , Córtex Pré-Frontal , Estimulação Magnética Transcraniana
10.
Front Psychol ; 11: 1458, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793026

RESUMO

Debate continues on whether a bilingual advantage exists with respect to executive functioning. This report synthesized the results of 170 studies to test whether the bilingual advantage is dependent on the task used to assess executive functioning and the age of the participants. The results of the meta-analyses indicated that the bilingual advantage was both task- and age-specific. Bilinguals were significantly faster than monolinguals (Hedges' g values ranged from 0.23 to 0.34), and significantly more accurate than monolinguals (Hedges' g values ranged between 0.18 and 0.49) on four out of seven tasks. Also, an effect of age was found whereby the bilingual advantage was larger for studies comprising samples aged 50-years and over (Hedges' g = 0.49), compared to those undertaken with participants aged between 18 and 29 years (Hedges' g = 0.12). The extent to which the bilingual advantage might be due to publication bias was assessed using multiple methods. These were Egger's Test of Asymmetry, Duval and Tweedie's Trim and Fill, Classic Fail-Safe N, and PET-PEESE. Publication bias was only found when using Egger's Test of Asymmetry and PET-PEESE method, but not when using the other methods. This review indicates that if bilingualism does enhance executive functioning, the effects are modulated by task and age. This may arise because using multiple languages has a highly specific effect on executive functioning which is only observable in older, relative to younger, adults. The finding that publication bias was not uniformly detected across the different methods raises questions about the impact that unpublished (or undetected) studies have on meta-analyses of this literature.

11.
Diagnostics (Basel) ; 10(7)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610595

RESUMO

This study sought to assess the value of multiparametric magnetic resonance image (mp-MRI) in patients with a prostate cancer (PCa) Gleason score of 6 or less under consideration for or already in active surveillance and to determine the rate of upgrading by target biopsy. Three hundred and fifty-four consecutive men with an initial transrectal ultrasound-guided (TRUS) biopsy-confirmed PCa Gleason score of 6 or less under clinical consideration for or already in active surveillance underwent mp-MRI and were retrospectively reviewed. One hundred and nineteen of 354 patients had cancer-suspicious regions (CSRs) at mp-MRI. Each CSR was assigned a Prostate Imaging Reporting and Data System (PI-RADS) score based on PI-RADS v2. One hundred and eight of 119 patients underwent confirmatory imaging-guided biopsy for CSRs. Pathology results including Gleason score (GS) and percentage of specimens positive for PCa were recorded. Associations between PI-RADS scores and findings at target biopsy were evaluated using logistic regression. At target biopsy, 81 of 108 patients had PCa (75%). Among them, 77 patients had upgrading (22%, 77 of 354 patients). One hundred and forty-six CSRs in 108 patients had PI-RADS 3 n = 28, 4 n = 66, and 5 n = 52. The upgraded rate for each category of CSR was for PI-RADS 3 (5 of 28, 18%), 4 (47 of 66, 71%) and 5 (49 of 52, 94%). Using logistic regression analysis, differences in PI-RADS scores from 3 to 5 are significantly associated with the probability of disease upgrade (20%, 73%, and 96% for PI-RADS score of 3, 4, and 5, respectively). Adding mp-MRI to patients under consideration for or already in active surveillance helps to identify undiagnosed PCa of a higher GS or higher volume resulting in upgrading in 22%.

12.
Front Hum Neurosci ; 14: 25, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32116609

RESUMO

Behavioral studies have shown that the ability to discriminate between non-native speech sounds improves after seeing how the sounds are articulated. This study examined the influence of visual articulatory information on the neural correlates of non-native speech sound discrimination. English speakers' discrimination of the Hindi dental and retroflex sounds was measured using the mismatch negativity (MMN) event-related potential, before and after they completed one of three 8-min training conditions. In an audio-visual speech training condition (n = 14), each sound was presented with its corresponding visual articulation. In one control condition (n = 14), both sounds were presented with the same visual articulation, resulting in one congruent and one incongruent audio-visual pairing. In another control condition (n = 14), both sounds were presented with the same image of a still face. The control conditions aimed to rule out the possibility that the MMN is influenced by non-specific audio-visual pairings, or by general exposure to the dental and retroflex sounds over the course of the study. The results showed that audio-visual speech training reduced the latency of the MMN but did not affect MMN amplitude. No change in MMN amplitude or latency was observed for the two control conditions. The pattern of results suggests that a relatively short audio-visual speech training session (i.e., 8 min) may increase the speed with which the brain processes non-native speech sound contrasts. The absence of a training effect on MMN amplitude suggests a single session of audio-visual speech training does not lead to the formation of more discrete memory traces for non-native speech sounds. Longer and/or multiple sessions might be needed to influence the MMN amplitude.

13.
Behav Neurosci ; 133(4): 341-349, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30869951

RESUMO

The primary motor area (M1) has been implicated in visuomotor sequence learning. However, it has been suggested there are multiple neural networks that undertake visuomotor sequence learning. The role of M1 in sequence learning may be specific to learning simple sequences comprising predictable associations between adjacent movements. This study aimed to investigate the role of M1 in learning simple ("first-order conditional") and more complex ("second-order conditional") sequences. It was hypothesized that continuous theta burst stimulation (cTBS) over M1 would result in poorer learning of the simple sequence only. Forty-eight healthy adults received cTBS to either M1 or the parietal lobe or received sham cTBS before immediately completing 2 visuomotor sequence learning tasks. The tasks only differed in relation to the structure (i.e., simple vs. complex) of the sequence. The group who received cTBS over M1 demonstrated significantly poorer learning of the simple sequence in comparison to the more complex sequence. The parietal lobe stimulation and sham stimulation did not affect learning of either sequence. This is the first study to show differential involvement of M1 in visuomotor sequence learning, dependent on sequence structure. The study provides new evidence that sequence learning might be supported by different networks in the brain. Specifically, M1 sequence learning appears to be important for learning simple item-to-item associations but not for more complex sequences. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Córtex Motor/fisiologia , Aprendizagem Seriada/fisiologia , Adulto , Atenção , Encéfalo , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Destreza Motora/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Ritmo Teta/fisiologia , Estimulação Magnética Transcraniana/métodos
14.
JMIR Ment Health ; 5(3): e54, 2018 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-30139722

RESUMO

BACKGROUND: Despite the growing number of mental health apps available for smartphones, the perceived usability of these apps from the perspectives of end users or health care experts has rarely been reported. This information is vital, particularly for self-guided mHealth interventions, as perceptions of navigability and quality of content are likely to impact participant engagement and treatment compliance. OBJECTIVE: The aim of this study was to conduct a usability evaluation of a personalized, self-guided, app-based intervention for depression. METHODS: Participants were administered the System Usability Scale and open-ended questions as part of a semistructured interview. There were 15 participants equally divided into 3 groups: (1) individuals with clinical depression who were the target audience for the app, (2) mental health professionals, and (3) researchers who specialize in the area of eHealth interventions and/or depression research. RESULTS: The end-user group rated the app highly, both in quantitative and qualitative assessments. The 2 expert groups highlighted the self-monitoring features and range of established psychological treatment options (such as behavioral activation and cognitive restructuring) but had concerns that the amount and layout of content may be difficult for end users to navigate in a self-directed fashion. The end-user data did not confirm these concerns. CONCLUSIONS: Encouraging participant engagement via self-monitoring and feedback, as well as personalized messaging, may be a viable way to maintain participation in self-guided interventions. Further evaluation is necessary to determine whether levels of engagement with these features enhance treatment effects.

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