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1.
Med Image Anal ; 95: 103207, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38776843

RESUMO

The lack of annotated datasets is a major bottleneck for training new task-specific supervised machine learning models, considering that manual annotation is extremely expensive and time-consuming. To address this problem, we present MONAI Label, a free and open-source framework that facilitates the development of applications based on artificial intelligence (AI) models that aim at reducing the time required to annotate radiology datasets. Through MONAI Label, researchers can develop AI annotation applications focusing on their domain of expertise. It allows researchers to readily deploy their apps as services, which can be made available to clinicians via their preferred user interface. Currently, MONAI Label readily supports locally installed (3D Slicer) and web-based (OHIF) frontends and offers two active learning strategies to facilitate and speed up the training of segmentation algorithms. MONAI Label allows researchers to make incremental improvements to their AI-based annotation application by making them available to other researchers and clinicians alike. Additionally, MONAI Label provides sample AI-based interactive and non-interactive labeling applications, that can be used directly off the shelf, as plug-and-play to any given dataset. Significant reduced annotation times using the interactive model can be observed on two public datasets.


Assuntos
Inteligência Artificial , Imageamento Tridimensional , Humanos , Imageamento Tridimensional/métodos , Algoritmos , Software
3.
IEEE Trans Med Imaging ; 42(7): 2044-2056, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37021996

RESUMO

Federated learning (FL) allows the collaborative training of AI models without needing to share raw data. This capability makes it especially interesting for healthcare applications where patient and data privacy is of utmost concern. However, recent works on the inversion of deep neural networks from model gradients raised concerns about the security of FL in preventing the leakage of training data. In this work, we show that these attacks presented in the literature are impractical in FL use-cases where the clients' training involves updating the Batch Normalization (BN) statistics and provide a new baseline attack that works for such scenarios. Furthermore, we present new ways to measure and visualize potential data leakage in FL. Our work is a step towards establishing reproducible methods of measuring data leakage in FL and could help determine the optimal tradeoffs between privacy-preserving techniques, such as differential privacy, and model accuracy based on quantifiable metrics.


Assuntos
Redes Neurais de Computação , Aprendizado de Máquina Supervisionado , Humanos , Privacidade , Informática Médica
5.
Placenta ; 104: 8-15, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33197856

RESUMO

INTRODUCTION: The timing of parturition at end of human gestation may be controlled by fetal signals. The signaling molecules contributing to activation of human labor may be mediated by fetal exosomes. In this study, we focused on investigation of the role of microRNAs (miRNAs) derived from fetal exosomes in the regulation of human placental gene expression. METHODS: Using immunofluorescent labeling, array-based miRNA profiling assay, target prediction analysis, and conducting a variety of biochemical approaches including miRNA mimics, dual-luciferase, siRNA-mediated gene silencing, and immunohistochemical staining assay in primary trophoblast culture and formalin-fixed paraffin-embedded placental tissues, we examined whether fetal exosomal miRNAs can stimulate expression of proinflammatory mediators in human placenta. RESULTS: We showed placental uptake of exosomes derived from the umbilical artery, and found that 9 fetal exosomal miRNAs: let-7i-5p, miR-185-5p, miR-15b-5p, miR-376c-3p, miR-548d-5p, miR-92b-3p, miR-16-5p, and miR-1301-3p were significantly increased in placentas of women delivering following term labor compared to those delivering by Cesarean section in the late preterm period. Target prediction analysis identified miR-15b-5p of particular interest, because one of its predicted targets is Apelin, a potent inhibitor of proinflammatory mediators. We further found that miR-15b-5p repressed Apelin protein levels and activated pro-labor hormones and cytokines including IL-1, IL-6, IL-8, and TNF-α. DISCUSSION: These data suggest a potential fetal-to-placental signal that could play a role in the length of human gestation and onset of human labor.


Assuntos
Apelina/metabolismo , Citocinas/metabolismo , Inflamação/metabolismo , MicroRNAs/metabolismo , Placenta/metabolismo , Transdução de Sinais/fisiologia , Adulto , Exossomos/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , MicroRNAs/genética , Gravidez
6.
Hawaii J Health Soc Welf ; 79(5 Suppl 1): 122-126, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32490399

RESUMO

Pediatric advanced life support (PALS) recertification every two years is inadequate to maintain proficiency. The authors hypothesized that a standardized, recurring curriculum may enhance retention of cardiopulmonary resuscitation (CPR) skills. Monthly in situ mock code training and an annual online self-directed learning module were implemented for pediatric intensive care unit nurses, pediatric residents, and respiratory therapists at a women and children's hospital. The in situ mock codes were linked to PALS training self-efficacy (pre- and post-mock code) and feedback related surveys. CPR knowledge was assessed using an online module with pre- and post-tests. A total of 82 in situ mock code surveys and 137 online modules were completed over a 20-month period. Medical knowledge (P < .05 for 7/10 questions) and self-confidence improved (P < .001. Several staff reported a negative impact on their patient care assignments in order to participate in the mock code. However, a significant number of participants (65%) concurred with the benefits of monthly mock codes. The curriculum improved CPR efficacy by improving knowledge-based retention as well as self-confidence in their skills.


Assuntos
Parada Cardíaca/terapia , Pediatria/normas , Autoeficácia , Autoavaliação (Psicologia) , Adulto , Competência Clínica/normas , Competência Clínica/estatística & dados numéricos , Feminino , Havaí/epidemiologia , Parada Cardíaca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Pediatria/métodos , Pediatria/estatística & dados numéricos , Inquéritos e Questionários
7.
Crit Care Med ; 48(1): e1-e8, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31688194

RESUMO

OBJECTIVE: Rapid advancements in medicine and changing standards in medical education require new, efficient educational strategies. We investigated whether an online intervention could increase residents' knowledge and improve knowledge retention in mechanical ventilation when compared with a clinical rotation and whether the timing of intervention had an impact on overall knowledge gains. DESIGN: A prospective, interventional crossover study conducted from October 2015 to December 2017. SETTING: Multicenter study conducted in 33 PICUs across eight countries. SUBJECTS: Pediatric categorical residents rotating through the PICU for the first time. We allocated 483 residents into two arms based on rotation date to use an online intervention either before or after the clinical rotation. INTERVENTIONS: Residents completed an online virtual mechanical ventilation simulator either before or after a 1-month clinical rotation with a 2-month period between interventions. MEASUREMENTS AND MAIN RESULTS: Performance on case-based, multiple-choice question tests before and after each intervention was used to quantify knowledge gains and knowledge retention. Initial knowledge gains in residents who completed the online intervention (average knowledge gain, 6.9%; SD, 18.2) were noninferior compared with those who completed 1 month of a clinical rotation (average knowledge gain, 6.1%; SD, 18.9; difference, 0.8%; 95% CI, -5.05 to 6.47; p = 0.81). Knowledge retention was greater following completion of the online intervention when compared with the clinical rotation when controlling for time (difference, 7.6%; 95% CI, 0.7-14.5; p = 0.03). When the online intervention was sequenced before (average knowledge gain, 14.6%; SD, 15.4) rather than after (average knowledge gain, 7.0%; SD, 19.1) the clinical rotation, residents had superior overall knowledge acquisition (difference, 7.6%; 95% CI, 2.01-12.97;p = 0.008). CONCLUSIONS: Incorporating an interactive online educational intervention prior to a clinical rotation may offer a strategy to prime learners for the upcoming rotation, augmenting clinical learning in graduate medical education.


Assuntos
Competência Clínica , Educação a Distância , Internato e Residência , Pediatria/educação , Respiração Artificial , Adulto , Estudos Cross-Over , Feminino , Humanos , Unidades de Terapia Intensiva Pediátrica , Masculino , Estudos Prospectivos , Treinamento por Simulação , Adulto Jovem
8.
MAbs ; 11(7): 1289-1299, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31199179

RESUMO

IgG4, a common type of therapeutic antibody, is less stable during manufacturing processes compared with IgG1. Aggregation and fragmentation are the two main challenges. Here, we report instability of the heavy chain (HC) C-terminal region under acidic conditions, which leads to cleavage and aggregation. Leu445, at the C-terminal region of the HC in IgG4, plays a critical role in its acid-induced fragmentation and subsequent aggregation. We found that mutating HC C-terminal Leu445 to Pro (the corresponding residue in IgG1) in IgG4_CDR-X significantly reduces fragmentation and aggregation, while mutating Pro445 to Leu in IgG1_CDR-X promotes fragmentation and aggregation. HC C-terminal Gly446 cleavage was observed in low pH citrate buffer and resulted in further fragmentation and aggregation, whereas, glycine buffer can completely inhibit the cleavage and aggregation. It is proposed that cleavages occur through acid-induced hydrolysis under acidic conditions and glycine stabilizes IgG4 via two main mechanisms: 1) product feedback inhibition of the hydrolysis reaction, and 2) stabilization of protein conformation by direct interaction with the peptide backbone and charged side chains. Experiments using IgG4 molecules IgG4_CDR-Y and IgG4_CDR-Z with the same CH domains as IgG4_CDR-X, but different complementarity-determining regions (CDRs), indicate that the stability of the HC C-terminal region is also closely related to the sequence of the CDRs. The stability of IgG4_CDR-X is significantly improved when binding to its target. Both observations suggest that there are potential interactions between Fab and CH2-CH3 domains, which could be the key factor affecting the stability of IgG antibodies.


Assuntos
Regiões Determinantes de Complementaridade/química , Glicina/química , Imunoglobulina G/química , Cadeias Pesadas de Imunoglobulinas/química , Fragmentos de Peptídeos/química , Regiões Determinantes de Complementaridade/genética , Glicina/genética , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Imunoglobulina G/genética , Cadeias Pesadas de Imunoglobulinas/genética , Mutação/genética , Fragmentos de Peptídeos/genética , Agregados Proteicos , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas/genética , Estabilidade Proteica , Proteólise
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