Publications by Year: 2026

OBJECTIVE: To evaluate national and international obstetric ultrasound guidelines regarding their recommendations for vasa previa (VP) screening, and to assess the consistency, scope and evidence base of the recommendations.

METHODS: We conducted a comprehensive review of accessible national obstetric imaging guidelines from 15 countries worldwide, as well as two international guidelines by the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG). Guidelines were assessed for whether they explicitly mentioned VP, recommended screening for VP or incorporated VP detection strategies, such as placental cord insertion assessment, color flow Doppler assessment of the lower uterine segment or third-trimester transvaginal ultrasound with color flow Doppler in patients with second-trimester placenta previa or low-lying placenta. Additionally, we evaluated whether any national societies or international organizations had specific guidelines on VP, which were then assessed for whether they included recommendations for VP screening and outlined specific screening policies or strategies.

RESULTS: Of 20 national and two international obstetric imaging guidelines reviewed, 12 mentioned VP and none explicitly recommended routine screening for VP in pregnant individuals. Nine national obstetric imaging guidelines recommended routine assessment of the placental cord insertion, while none endorsed routine color flow Doppler assessment of the lower uterine segment. Five national guidelines recommended third-trimester transvaginal ultrasound examination with color flow Doppler to rule out VP in pregnancies with a second-trimester low-lying placenta or placenta previa. In our search, only five national societies were found to have developed dedicated VP guidelines, although some of their recommendations were inconsistent with recent evidence. For example, the 2019 guideline from the Royal College of Obstetricians and Gynaecologists in the UK does not recommend routine VP screening, citing insufficient evidence and an uncertain balance of benefit vs harm.

CONCLUSIONS: Despite the high mortality rate associated with undiagnosed VP and the mounting evidence supporting the feasibility of screening, many national and international obstetric imaging guidelines either omit mention of VP or fall short of recommending a structured screening approach. Given the demonstrated accuracy of VP screening, its remarkable impact in reducing the rate of VP-related stillbirth and the minimal additional resources required for VP detection strategies, current imaging guidelines should be updated to incorporate evidence-based VP screening strategies into routine obstetric imaging protocols to reduce preventable perinatal deaths. © 2026 International Society of Ultrasound in Obstetrics and Gynecology.

PURPOSE: Claims data are a valuable source to study neonatal outcomes across a wide range of clinical questions. Infants' delayed enrollment in infant insurance poses challenges in capture of neonatal outcomes, which may be charged to the maternal health plan, posing misclassification risks. We evaluated outcome ascertainment across three infant enrollment scenarios.

METHODS: We used Merative MarketScan databases (2012-2018) in the United States to construct a mother-infant linked cohort and assess the outcome ascertaiment precision with varying infant enrollment requirement.

RESULT: We found that allowing delayed infant enrollment in their own insurance within the first 4 weeks of life retained sample size, nearly doubled case numbers and yielded outcome prevalences similar to those of cohorts with full enrollment since birth. Use of maternal claims in addition to infant claims in this cohort made minor contributions to case capture for neonatal-specific outcomes, while significantly decreasing specificity of more general outcomes. Longer delays in enrollment yielded lower outcome prevalences with higher contributions of maternal claims even for neonatal-specific outcomes. For small for gestational age (SGA), both maternal and infant claims contributed similar proportions of cases.

CONCLUSION: These findings inform strategies for outcome ascertainment in claims-based perinatal research and emphasize outcome-specific case ascertainment strategies to balance sensitivity and specificity.

Symptoms of schizophrenia may reflect different pathophysiological processes in the striatum, but the links between striatal subfield connectivity, symptom dimensions, and molecular architectures remain unclear. Using connectivity profiles from 12 striatal subfields to predict negative, positive, affective, and cognitive symptoms in schizophrenia, we identified consistent connectivity features through cross-validations and validated with leave-one-site-out analysis and an independent dataset. Feature importance scores for brain parcels linked through consistent connectivity features that predicted symptoms were spatially correlated with density maps of 19 receptors/transporters from prior molecular imaging in healthy populations using partial least squares. We found that the connectivity profiles of the rostral and ventral striatal subfields significantly predicted affective and cognitive symptoms, respectively, and these predictions were generalized to the independent sample. Feature importance scores for brain parcels connected to the ventral striatum (predicting cognitive symptoms) were spatially correlated with density maps of both the vesicular acetylcholine transporter and the serotonin 1 A receptor. By contrast, importance scores for parcels linked to rostral striatal connectivity (predicting affective symptoms) were specifically associated with the spatial distribution of the serotonin 1 A receptor. Here, we show specific striatal connectivity patterns related to symptom dimensions and indicate multiple neurotransmitter systems to underlie the reward-related disturbances in schizophrenia.

The association between vaccine efficacy (VE) and force of infection (FoI) remains incompletely understood. Previous analyses have been primarily based on trial-level summary data-not accounting for the effect of time and constrained by the number of trials. Here, we leverage individual-level data from three phase 3 randomized, placebo-controlled COVID-19 vaccine trials-the COVE trial (Moderna, CoVPN3001), the AZD1222 trial (AstraZeneca, CoVPN3002), and the ENSEMBLE trial (Janssen/Johnson & Johnson, CoVPN3003)-and contemporaneous geographic-location-specific SARS-CoV-2 surveillance data from the start of the pandemic through November 14, 2021 (including the blinded follow-up periods of the trials) to conduct five cohort- and vaccine-specific analyses: COVE (U.S.), AZD1222 overall (U.S. + non-U.S.), AZD1222 U.S., ENSEMBLE overall (U.S. + non-U.S.), and ENSEMBLE U.S. In AZD1222 U.S., higher VE was associated with higher FoI (p = 0.01). In ENSEMBLE overall, lower VE was marginally associated with higher FoI (p = 0.21), further supported by a region-specific analysis. In COVE, AZD1222 overall, and ENSEMBLE U.S., no VE-FoI association was found. These findings highlighted a new perspective: the VE-FoI association appears complex, potentially influenced by FoI levels, with patterns suggesting an inverted U-shaped relationship, showing a positive association at low FoI levels and a negative association at high levels.

Zika virus (ZIKV) vaccine development has been hindered by the risk of antibody-dependent enhancement (ADE), particularly in dengue-endemic regions, where sub-neutralizing antibodies can exacerbate disease severity. T cell-based vaccines targeting non-structural (NS) antigens represent a safer alternative that bypasses this risk. Using immunocompetent BALB/c mice, we performed high-resolution in vivo mapping of ZIKV specific CD8⁺ and CD4⁺ T cell responses following ZIKVPRVABC59 infection, identifying high avidity, polyfunctional memory T cells targeting conserved NS1, NS3 and NS4 proteins. Guided by these data, we developed DNA vaccines encoding full-length NS3 and NS4 and evaluated their efficacy against ZIKV infection alone or combined with a validated construct encoding secreted NS1 (p-tpaNS1). NS3 and NS4 vaccination elicited robust cytotoxic and IFN-γ producing T cell responses, while co-administration with p-tpaNS1 significantly reduced peak serum viremia achieving earlier and stronger viral control. Although NS1 alone conferred strong protection, the multi-antigen formulation demonstrated additive benefits. This T cell-based vaccine approach, targeting conserved NS proteins, offers a scalable, thermostable platform with potential for safe deployment in childbearing women and resource-limited regions. Given NS protein conservation and cross-reactivity across flaviviruses, it also provides a promising foundation for next-generation pan-flavivirus vaccine development, although this remains to be directly tested.

BACKGROUND: Regular assessments of Patient Safety Culture (PSC) are recommended by the World Health Organization to strengthen healthcare systems. In Brazil, despite national campaigns, hospital adherence to PSC assessments has remained low. This study aimed to design a tailored implementation strategy to improve the uptake of PSC assessments in Brazilian hospitals, addressing the key barriers faced in previous national efforts.

METHODS: We conducted a sequential exploratory mixed-methods study in three phases. First, a qualitative survey with 82 patient safety center coordinators identified perceived barriers and facilitators to implementing PSC assessments. Then, a quantitative survey with 297 coordinators prioritized the most relevant barriers. Finally, we used the Consolidated Framework for Implementation Research (CFIR) and the Expert Recommendations for Implementation Change (ERIC) to guide the design of a tailored implementation strategy aligned with the prioritized barriers.

RESULTS: The main barriers included insufficient dissemination of PSC assessments, lack of training for staff, resistance to completing the survey, the excessive length of the questionnaire, and technical limitations of the data collection platform. The co-design implementation strategy includes 16 actions such as improving communication, offering training, adapting the technology platform, and revising roles and responsibilities within hospitals. These actions were aligned with the identified barriers and aim to enhance organizational readiness, reduce complexity, and promote engagement.

CONCLUSIONS: Our findings highlight critical factors limiting the adoption of PSC assessments in Brazil and offer a data-driven, context-sensitive implementation strategy to overcome them. These results provide actionable recommendations for policymakers, healthcare managers, and regulators aiming to strengthen patient safety culture in large-scale, resource-constrained health systems.

Diet plays a crucial role in health, with low-carbohydrate diets often proposed to exert metabolic benefits. We aim to investigate metabolomic adaptations in 164 adults with overweight or obesity who were randomly assigned to high- (n = 54), moderate- (n = 53), or low-carbohydrate (n = 57) diets during a 20-week weight-loss maintenance phase of the Framingham State Food Study [(FS)2], a controlled, parallel feeding trial (ClinicalTrials.gov: NCT02068885). We measure fasting plasma metabolites by liquid chromatography-tandem mass spectrometry using samples from 147 participants who completed the study (n = 45, 48, and 54 in the high-, moderate-, and low-carbohydrate diet groups, respectively). Significant associations (False Discovery Rate<0.05) are identified between carbohydrate-to-fat ratio (CFR) and diet-induced changes in 148 of 479 metabolites at 20 weeks, with nearly all showing consistent trends at 10 and 20 weeks. Phosphatidylcholines plasmanyls/plasmalogens, phosphatidylethanolamines plasmanyls/plasmalogens, and sphingomyelins generally decrease with higher CFR, whereas lysophosphatidylcholines, lysophosphatidylethanolamines, and triglycerides generally increase. Our findings are largely reproducible in an independent feeding trial involving diets with similar CFR (Popular Diets Study, ClinicalTrials.gov: NCT00315354). Eleven triglyceride species (≤3 double bonds), linked to type 2 diabetes risk, increase with higher CFR. Our findings demonstrate metabolomic changes caused by varying CFR dietary patterns, offering potential insights into mechanisms that could guide targeted dietary intervention strategies.

BACKGROUND: This study presents the first process evaluation of an integrated family planning, sexual reproductive health, and wellbeing community-based intervention among Syrian refugee women and girls in Lebanon. This intervention, known as the Self-Efficacy and Knowledge (SEEK) intervention, was developed by the World Health Organization as a low-resource and low-intensity initiative, and led by trained paraprofessionals (community health workers).

METHODS: The intervention was implemented between September and December 2024, a period marked by active conflict in Lebanon. A mixed-methods process evaluation was conducted, triangulating data from satisfaction surveys, field observations, and semi-structured interviews with participants, health workers, and program staff. Quantitative data were analyzed using SPSS, and qualitative data were analyzed using qualitative content analysis. Data collection tools assessed satisfaction, feasibility, fidelity to content, logistical and contextual barriers.

RESULTS: The evaluation revealed high participant satisfaction, with over 90% of participants rating session quality as good or excellent. Participants valued the program’s relevance, paraprofessionals community alignment, and the inclusion of interactive and visual aids. Paraprofessionals expressed satisfaction with the training and delivery process but, along with attending psychologists and midwives, reported the need for more soft-skills training and presentation skills. Logistical challenges included child care needs, transportation barriers, and the necessity of flexible scheduling. The war on Lebanon posed major implementation hurdles, requiring adaptive strategies such as remote coordination and increased reliance on leadership of local staff. Cultural and gender norms affected engagement, particularly around SRH content, with participants recommending greater involvement of men and household decision-makers. The presence of local women committees, research assistants, and field coordinators was key to maintaining trust, communication, and retention of participants.

CONCLUSIONS: This evaluation demonstrates that SEEK is feasible, acceptable, and adaptable even in the context of active conflict. Its community-led design supported engagement and delivery, underscoring the importance of flexible and locally grounded implementation strategies in fragile settings.

TRIAL REGISTRATION: Retrospectively registered on NIH clinical trials reference# NCT07008950.

Spatial omics links molecular measurements to their positions in tissue, revealing cellular organization and interactions. Yet most computational tools highlight common cell types and overlook rare populations that can drive disease. Here we show GARDEN, a computational framework that identifies and characterizes these pathogenic cells or regions in spatial omics by embedding graph-based dynamic attention into a spatially-aware graph fusion contrastive model. GARDEN works consistently across tissues, species and resolution scales, and aligns consecutive sections to reconstruct 3D anatomy. In an Alzheimer's disease model, GARDEN localizes C1qa/C1qb-marked microglia in amyloid-β regions and reveals key immune pathways. In nasopharyngeal carcinoma it identifies tiny tertiary lymphoid structures, and in breast cancer it uncovers inflammatory M1-like macrophages near ductal carcinoma in situ and links them to pro-metastatic signaling. An interpretation module pinpoints key immune signatures, and GARDEN extends to spatial chromatin accessibility, providing insight into epigenetic regulation and informing diagnostics and therapeutic targeting.