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8.
JAMA Intern Med ; 183(6): 589-596, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37115527

RESUMO

Importance: The rapid expansion of virtual health care has caused a surge in patient messages concomitant with more work and burnout among health care professionals. Artificial intelligence (AI) assistants could potentially aid in creating answers to patient questions by drafting responses that could be reviewed by clinicians. Objective: To evaluate the ability of an AI chatbot assistant (ChatGPT), released in November 2022, to provide quality and empathetic responses to patient questions. Design, Setting, and Participants: In this cross-sectional study, a public and nonidentifiable database of questions from a public social media forum (Reddit's r/AskDocs) was used to randomly draw 195 exchanges from October 2022 where a verified physician responded to a public question. Chatbot responses were generated by entering the original question into a fresh session (without prior questions having been asked in the session) on December 22 and 23, 2022. The original question along with anonymized and randomly ordered physician and chatbot responses were evaluated in triplicate by a team of licensed health care professionals. Evaluators chose "which response was better" and judged both "the quality of information provided" (very poor, poor, acceptable, good, or very good) and "the empathy or bedside manner provided" (not empathetic, slightly empathetic, moderately empathetic, empathetic, and very empathetic). Mean outcomes were ordered on a 1 to 5 scale and compared between chatbot and physicians. Results: Of the 195 questions and responses, evaluators preferred chatbot responses to physician responses in 78.6% (95% CI, 75.0%-81.8%) of the 585 evaluations. Mean (IQR) physician responses were significantly shorter than chatbot responses (52 [17-62] words vs 211 [168-245] words; t = 25.4; P < .001). Chatbot responses were rated of significantly higher quality than physician responses (t = 13.3; P < .001). The proportion of responses rated as good or very good quality (≥ 4), for instance, was higher for chatbot than physicians (chatbot: 78.5%, 95% CI, 72.3%-84.1%; physicians: 22.1%, 95% CI, 16.4%-28.2%;). This amounted to 3.6 times higher prevalence of good or very good quality responses for the chatbot. Chatbot responses were also rated significantly more empathetic than physician responses (t = 18.9; P < .001). The proportion of responses rated empathetic or very empathetic (≥4) was higher for chatbot than for physicians (physicians: 4.6%, 95% CI, 2.1%-7.7%; chatbot: 45.1%, 95% CI, 38.5%-51.8%; physicians: 4.6%, 95% CI, 2.1%-7.7%). This amounted to 9.8 times higher prevalence of empathetic or very empathetic responses for the chatbot. Conclusions: In this cross-sectional study, a chatbot generated quality and empathetic responses to patient questions posed in an online forum. Further exploration of this technology is warranted in clinical settings, such as using chatbot to draft responses that physicians could then edit. Randomized trials could assess further if using AI assistants might improve responses, lower clinician burnout, and improve patient outcomes.


Assuntos
Médicos , Mídias Sociais , Humanos , Inteligência Artificial , Estudos Transversais , Idioma
9.
Nat Commun ; 14(1): 726, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759609

RESUMO

Transcription must be tightly controlled to regulate gene expression and development. However, our understanding of the molecular mechanisms that influence transcription and how these are coordinated in cells to ensure normal gene expression remains rudimentary. Here, by dissecting the function of the SET1 chromatin-modifying complexes that bind to CpG island-associated gene promoters, we discover that they play a specific and essential role in enabling the expression of low to moderately transcribed genes. Counterintuitively, this effect can occur independently of SET1 complex histone-modifying activity and instead relies on an interaction with the RNA Polymerase II-binding protein WDR82. Unexpectedly, we discover that SET1 complexes enable gene expression by antagonising premature transcription termination by the ZC3H4/WDR82 complex at CpG island-associated genes. In contrast, at extragenic sites of transcription, which typically lack CpG islands and SET1 complex occupancy, we show that the activity of ZC3H4/WDR82 is unopposed. Therefore, we reveal a gene regulatory mechanism whereby CpG islands are bound by a protein complex that specifically protects genic transcripts from premature termination, effectively distinguishing genic from extragenic transcription and enabling normal gene expression.


Assuntos
Histonas , Transcrição Gênica , Ilhas de CpG/genética , Histonas/metabolismo , Cromatina/genética , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Metilação de DNA/genética
10.
Longit Life Course Stud ; 15(1): 5-18, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38174546

RESUMO

This commentary reinforces a central commitment of life course research: to make visible how social change matters in human lives. This paper captures a moderated conversation with four senior scholars about how they came to study the intersection between social change and life experience, why this intersection is so important to life course studies, and theoretical and methodological imperatives and challenges that come with it.


Assuntos
Acontecimentos que Mudam a Vida , Mudança Social , Humanos
17.
Life (Basel) ; 11(4)2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33801697

RESUMO

This report was designed to compare spaceflight-induced cellular and physiological adaptations of Candida albicans cultured in microgravity on the International Space Station across several payloads. C. albicans is a common opportunistic fungal pathogen responsible for a variety of superficial infections as well as systemic and more severe infections in humans. Cumulatively, the propensity of this organism to be widespread through the population, the ability to produce disease in immunocompromised individuals, and the tendency to respond to environmental stress with characteristics associated with increased virulence, require a better understanding of the yeast response to microgravity for spaceflight crew safety. As such, the responses of this yeast cultivated during several missions using two in-flight culture bioreactors were analyzed and compared herein. In general, C. albicans had a slightly shorter generation time and higher growth propensity in microgravity as compared to terrestrial controls. Rates of cell filamentation differed between bioreactors, but were low and not significantly different between flight and terrestrial controls. Viable cells were retrieved and cultured, resulting in a colony morphology that was similar between cells cultivated in flight and in terrestrial control conditions, and in contrast to that previously observed in a ground-based microgravity analog system. Of importance, yeast demonstrated an increased resistance when challenged during spaceflight with the antifungal agent, amphotericin B. Similar levels of resistance were not observed when challenged with the functionally disparate antifungal drug caspofungin. In aggregate, yeast cells cultivated in microgravity demonstrated a subset of characteristics associated with virulence. In addition, and beyond the value of the specific responses of C. albicans to microgravity, this report includes an analysis of biological reproducibility across flight opportunities, compares two spaceflight hardware systems, and includes a summary of general flight and payload timelines.

19.
Biochim Biophys Acta Gene Regul Mech ; 1863(8): 194567, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32360393

RESUMO

The precise regulation of gene transcription is required to establish and maintain cell type-specific gene expression programs during multicellular development. In addition to transcription factors, chromatin, and its chemical modification, play a central role in regulating gene expression. In vertebrates, DNA is pervasively methylated at CG dinucleotides, a modification that is repressive to transcription. However, approximately 70% of vertebrate gene promoters are associated with DNA elements called CpG islands (CGIs) that are refractory to DNA methylation. CGIs integrate the activity of a range of chromatin-regulating factors that can post-translationally modify histones and modulate gene expression. This is exemplified by the trimethylation of histone H3 at lysine 4 (H3K4me3), which is enriched at CGI-associated gene promoters and correlates with transcriptional activity. Through studying H3K4me3 at CGIs it has become clear that CGIs shape the distribution of H3K4me3 and, in turn, H3K4me3 influences the chromatin landscape at CGIs. Here we will discuss our understanding of the emerging relationship between CGIs, H3K4me3, and gene expression.


Assuntos
Ilhas de CpG/genética , Histonas/genética , Histonas/metabolismo , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Animais , Cromatina , Metilação de DNA , Proteínas de Ligação a DNA , Regulação da Expressão Gênica , Histona-Lisina N-Metiltransferase , Proteína de Leucina Linfoide-Mieloide , Proteínas de Neoplasias , Transcrição Gênica
20.
Pract Radiat Oncol ; 10(5): 330-338, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32014615

RESUMO

PURPOSE: To compare heart and lung doses for adjuvant whole breast irradiation (WBI) between radiation plans generated supine with deep inspiratory breath hold (S-DIBH) and prone with free-breathing (P-FB) and examine the effect of breast volume (BV) on dosimetric parameters. METHODS AND MATERIALS: Patients with left breast ductal carcinoma in situ or invasive cancer receiving adjuvant WBI were enrolled on a single-institutional prospective protocol. Patients were simulated S-DIBH and P-FB; plans were generated using both scans. Wilcoxon signed-rank and rank-sum tests were used to compare intrapatient differences between plans for the entire cohort and within BV groups defined by tertiles. RESULTS: Forty patients were enrolled. Thirty-four patients are included in the analysis owing to patient withdrawal or inability to hold breath. With WBI dose of 4005 to 4256 cGy, mean heart dose (MHD) was 80 cGy in S-DIBH and 77 cGy in P-FB (P = .08). Mean ipsilateral lung dose (MLD) was 453 cGy in S-DIBH and 45 cGy in P-FB (P < .0001). Mean and max left anterior descending artery doses were 251 cGy and 551 cGy in S-DIBH, respectively (P = .1), and 324 cGy and 993 cGy in P-FB, respectively (P = .3). Hot spot and separation were 109% and 22 cm in S-DIBH, respectively, and 107% and 16 cm in P-FB, respectively (P < .0001). For patients with smallest BV, S-DIBH improved MHD and left anterior descending artery doses; for those with largest BV, P-FB improved cardiac dosimetry. With increasing BV, there was an increasing advantage of P-FB for MHD (P = .05), and max (P = .03) and mean (P = .02) left anterior descending artery doses, and the reduction in MLD, hot spot, and separation with P-FB increased (P < .05). CONCLUSIONS: MHD did not differ between P-FB and S-DIBH, whereas MLD was significantly lower with P-FB. Analysis according to breast volume revealed improved cardiac dosimetry with S-DIBH for women with smallest BV and improved cardiac dosimetry with P-FB for women with larger BV, thereby providing a dosimetric rationale for using breast size to help determine the optimal positioning for WBI.


Assuntos
Suspensão da Respiração , Neoplasias da Mama/radioterapia , Feminino , Coração , Humanos , Órgãos em Risco , Estudos Prospectivos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
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