Multi-Modal Digital Impressions For Palatal Defects

INTRODUCTION

This in-vitro study investigated limitations of intra-oral scanners (IOS) in capturing palatal defects at decreased mouth openings. The trueness and precision of composite 3D-printed models from Cone-Beam Computed Tomography (CBCT) and IOS were measured.

METHODS

A partially dentate palatal defect model was scanned with IOS (3M™TrueDefinition) at various simulated mouth openings. Five silicone impressions were poured in gypsum. Scans were taken using 3M™TrueDefinition; Planmeca Planscan®, n=5 each. Model was scanned on two CBCT (PlanmecaProFace®; Accuitomo170®CBCT, n=5 each). Geomagic®Control2014™ was used to create composite-models merging CBCT with IOS. Thirty composite-models were 3D-printed. Trueness and precision were measured. Pearson Correlation Coefficients measured correlation between mouth opening and data capture. Data analysed using Kruskal-Wallis, Wilcoxon rank-sum, and ANOVA. Statistical significance inferred when p⟨0.05.

RESULTS

Mouth openings ⟨20mm, IOS didn't capture information of soft tissue. Increased mouth opening positively correlated with increased data capture(r=0.93, p=0.001). AccuitomoCBCT and TrueDefinition IOS composite-models had the highest (trueness) and [precision](median (IQR) 0.172 mm(0.062-0.426)); [mean [SD] 0.080 mm [0.008]]. Casts had the lowest results (median (IQR) 0.289 mm(0.119-1.565));[mean [SD] 0.338 mm [0.089]](p⟨0.001).

CONCLUSION

Mouth opening ⟨20mm resulted in insufficient data capture by IOS for clinical applications. Composite digital models showed promising trueness and precision results.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

The effect of fibre cell remodelling on the power and optical quality of the lens

Vertebrate eye lenses are uniquely adapted to form a refractive index gradient (GRIN) for improved acuity, and to grow slowly in size despite constant cell proliferation. The mechanisms behind these adaptations remain poorly understood. We hypothesize that cell compaction contributes to both. To test this notion, we examined the relationship between lens size and shape, refractive characteristics and the cross-sectional areas of constituent fibre cells in mice of different ages. We developed a block-face imaging method to visualize cellular cross sections and found that the cross-sectional areas of fibre cells rose and then decreased over time, with the most significant reduction occurring in denucleating cells in the adult lens cortex, followed by cells in the embryonic nucleus. These findings help reconcile differences between the predictions of lens growth models and empirical data. Biomechanical simulations suggested that compressive forces generated from continuous deposition of fibre cells could contribute to cellular compaction. However, optical measurements revealed that the GRIN did not mirror the pattern of cellular compaction, implying that compaction alone cannot account for GRIN formation and that additional mechanisms are likely to be involved.

Molecular dynamics modelling of the interaction of a synthetic zinc-finger miniprotein with DNA

We report the modelling of the DNA complex of an artificial miniprotein composed of two zinc finger modules and an AT-hook linking peptide. The computational study provides for the first time a structural view of these types of complexes, dissecting interactions that are key to modulate their stability. The relevance of these interactions was validated experimentally. These results confirm the potential of this type of computational approach for studying peptide-DNA complexes and suggest that they could be very useful for the rational design of non-natural, DNA binding miniproteins.

Cost-Effectiveness Analysis of 68Ga-DOTATATE PET/MRI in Radiotherapy Planning in Patients with Intermediate-Risk Meningioma

BACKGROUND AND PURPOSE

While contrast-enhanced MR imaging is the criterion standard in meningioma diagnosis and treatment response assessment, gallium 68Ga-DOTATATE PET/MR imaging has increasingly demonstrated utility in meningioma diagnosis and management. Integrating 68Ga-DOTATATE PET/MR imaging in postsurgical radiation planning reduces the planning target volume and organ-at-risk dose. However, 68Ga-DOTATATE PET/MR imaging is not widely implemented in clinical practice due to higher perceived costs. Our study analyzes the cost-effectiveness of 68Ga-DOTATATE PET/MR imaging for postresection radiation therapy planning in patients with intermediate-risk meningioma.

MATERIALS AND METHODS

We developed a decision-analytical model based on both recommended guidelines on meningioma management and our institutional experience. Markov models were implemented to estimate quality-adjusted life-years (QALY). Cost-effectiveness analyses with willingness-to-pay thresholds of $50,000/QALY and $100,000/QALY were performed from a societal perspective. Sensitivity analyses were conducted to validate the results. Model input values were based on published literature.

RESULTS

The cost-effectiveness results demonstrated that 68Ga-DOTATATE PET/MR imaging yields higher QALY (5.47 versus 5.05) at a higher cost ($404,260 versus $395,535) compared with MR imaging alone. The incremental cost-effectiveness ratio analysis determined that 68Ga-DOTATATE PET/MR imaging is cost-effective at a willingness to pay of $50,000/QALY and $100,000/QALY. Furthermore, sensitivity analyses showed that 68Ga-DOTATATE PET/MR imaging is cost-effective at $50,000/QALY ($100,000/QALY) for specificity and sensitivity values above 76% (58%) and 53% (44%), respectively.

CONCLUSIONS

68Ga-DOTATATE PET/MR imaging as an adjunct imaging technique is cost-effective in postoperative treatment planning in patients with meningiomas. Most important, the model results show that the sensitivity and specificity cost-effective thresholds of 68Ga-DOTATATE PET/MR imaging could be attained in clinical practice.

Risk factors for fixation failure in intertrochanteric fractures treated with cephalomedullary nailing: a retrospective study of 251 patients

This study aimed to identify the variables associated with fixation failure in intertrochanteric fractures treated with cephalomedullary nailing (CMN). We retrospectively analyzed 251 consecutive patients who underwent surgery between January 2016 and July 2019. In order to identify predictors of failure (cut-out, cut-through, and/or nonunion), we analyzed: gender, age, fracture stability (according to the AO/OTA Classification), femoral neck angle (FNA), FNA as compared to the contralateral hip, lag screw position, and tip-apex distance (TAD). The failure rate was 9.6%: there were 10 cut-outs (4%), 7 non-unions (2.8%), and 7 cut-throughs (2.8%). Univariate logistic regression analysis showed that the risk factors for fixation failure were: female sex (p= 0.018), FNA <125° (p= 0.003), a difference in FNA of 7.5° as compared to the contralateral hip on the lateral radiograph (p= <0.0001), superior (p= 0.0141) and anterior position (p= <0.0001) of the lag screw, and TAD >25mm (p= 0.016). According to the multivariate analysis, female gender (OR 12.92 ; p 0.0019), the difference in FNA on the lateral view (OR 1.36; p < 0.001), and the anterior position of the screw in the femoral head (OR14.01;p <0.001) were confirmed as independent predictors of failure. In order to avoid failures in intertrochanteric hip fractures treated with CMN, this study confirmed the importance of achieving an accurate reduction on the lateral plane and avoiding the anterior position of the screw on the femoral head.

Zirconium-Catalyzed C-H Alumination of Polyolefins, Paraffins, and Methane

C-H/Et-Al exchange in zirconium-catalyzed reactions of saturated hydrocarbons and AlEt₃ affords versatile organoaluminum compounds and ethane. The grafting of commercially available Zr(OtBu)₄ on silica/alumina gives monopodal ≡SiO-Zr(OtBu)₃ surface pre-catalyst sites that are activated in situ by ligand exchange with AlEt₃. The catalytic C-H alumination of dodecane at 150 °C followed by quenching in air affords n-dodecanol as the major product, revealing selectivity for methyl group activation. Shorter hydrocarbon or alcohol products were not detected under these conditions. Catalytic reactions of cyclooctane and AlEt₃, however, afford ring-opened products, indicating that C-C bond cleavage occurs readily in methyl group-free reactants. This selectivity for methyl group alumination enables the C-H alumination of polyethylenes, polypropylene, polystyrene, and poly-α-olefin oils without significant chain deconstruction. In addition, the smallest hydrocarbon, methane, undergoes selective mono-alumination under solvent-free catalytic conditions, providing a direct route to Al-Me species.

Development, Implementation, and Evaluation of a Distance Learning and Telementoring Program for Cervical Cancer Prevention in Cameroon

IMPORTANCE

Although Africa has the highest burden of cervical cancer in the world, educational resources to achieve the 90-70-90 targets set by the World Health Organization in its strategy to eliminate cervical cancer are lacking in the region.

OBJECTIVES

To adapt, implement, and evaluate the Project Extension for Community Health Care Outcomes (ECHO), an innovative learning tool, to build capacity of clinicians to better incorporate new evidence-based guidelines into cervical cancer control policies and clinical practices.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study assessed knowledge and practices of clinicians and support staff regarding cervical cancer prevention and control and compared them among respondents who had attended Project ECHO sessions (prior ECHO attendees) with those who had not but were planning on attending in the near future (newcomers) as part of the Cameroon Cervical Cancer Prevention Project ECHO. Satisfaction of prior ECHO attendees was also evaluated. Data were analyzed from January to March 2022.

MAIN OUTCOMES AND MEASURES

Main outcomes were practices and knowledge regarding cervical cancer education and prevention and preinvasive management procedures compared among prior ECHO attendees and newcomers.

RESULTS

Of the 75 participants (mean [SD] age, 36.4 [10.0] years; 65.7% [95% CI, 54.3%-77.1%] women) enrolled in this study, 41 (54.7%; 95% CI, 43.1%-66.2%) were prior ECHO attendees, and most were clinicians (55 respondents [78.6%; 95% CI, 68.7%-88.4%]). Overall, 50% (95% CI, 37.8%-62.2%) of respondents reported performing cervical cancer screening with visual inspection of the cervix after application of acetic acid (VIA) and/or visual inspection of the cervix after application of Lugol's iodine (VILI), 46.3% (95% CI, 34.0%-58.5%) of respondents reported performing human papillomavirus (HPV) testing, and 30.3% (95% CI, 18.9%-41.7%) of respondents reported performing cervical cytological examination in their practices, Approximately one-fourth of respondents reported performing cryotherapy (25.4% [95% CI, 14.7%-36.1%]), thermal ablation (27.3% [95% CI, 16.2%-38.3%]) or loop electrosurgical excisional procedure (LEEP, 25.0% [95% CI, 14.4%-35.6%]) for treatment of preinvasive disease. The clinical use of many of these screening and treatment tools was significantly higher among prior ECHO attendees compared with newcomers (VIA/VILI: 63.2% [95% CI, 47.4%-78.9%] vs 33.3% [95% CI, 16.0%-50.6%]; P = .03; cryotherapy: 40.5% [95% CI, 24.3%-56.8%] vs 6.7% [95% CI, 0.0%-15.8%]; P = .002; thermal ablation: 43.2% [95% CI, 26.9%-59.6%] vs 6.9% [95% CI, 0.0%-16.4%]; P = .002). Knowledge about cervical cancer education, prevention, and management procedures was satisfactory in 36.1% (95% CI, 23.7%-48.5%) of respondents; this proportion was significantly higher among prior ECHO attendees (53.8% [95% CI, 37.7%-69.9%]) compared with newcomers (4.5% [95% CI, 0.0%-13.5%]; P < .001). Approximately two-thirds of participants (68.8% [95% CI, 51.8%-85.8%]) reported that they had applied knowledge learned in our ECHO sessions to patient care in their practice or adopted best-practice care through their participation in this ECHO program.

CONCLUSIONS AND RELEVANCE

These findings suggest that the Project ECHO e-learning and telementoring program was associated with improved skills for clinicians and support staff and enhanced quality of care for patients. In the COVID-19 era and beyond, reinforced efforts to strengthen cervical cancer knowledge and best practices through distance learning and collaboration are needed.

Ring Contraction of a Tungstacyclopentane Supported on Silica: Direct Conversion of Ethylene to Propylene

The reaction of W(NAr)(¹³C₄H₈)(OSiPh₃)₂ (1) (NAr = 2,6-diisopropylphenylimido) with silica partially dehydroxylated at 700 °C (SiO_2-700) is highly dependent on the reaction conditions. The primary product of this reaction is W(NAr)(¹³C₄H₈)(OSiPh₃)(OSi(O-)₃) (2) when the reaction is carried out in the dark. Grafting 1 onto SiO_2-700 in ambient lab light results in the formation of 2, W(NAr)(¹³CH₂¹³CH₂)(OSiPh₃)(OSi(O-)₃) (4), and one isomer of square-pyramidal W(NAr)(¹³CH₂¹³CH(¹³Me)¹³CH₂)(OSiPh₃)(OSi(O-)₃) (3). Heating 2 to 85 °C for 6 h results in the formation of 3, 4, W(NAr)(¹³CH(¹³Me)¹³CH₂¹³CH₂)(OSiPh₃)(OSi(O-)₃) (5), and W(NAr)((¹³CH₂)₂¹³CH(¹³Me)(¹³CH₂)₂)(OSiPh₃)(OSi(O-)₃) (6). Photolysis of 2 with blue LEDs (λ_max = 450 nm) produces 4, both isomers of 3, 5, and free ethylene. In the presence of excess ethylene and blue LED irradiation at 85 °C, 1/SiO_2-700 catalyzes the direct conversion of ethylene to propylene.

Profile and prognosis of patients with heart failure with recovered ejection fraction

Background

Patients with heart failure (HF) and reduced ejection fraction (rEF) have a poor prognosis. Nevertheless, in the subgroup of patients with recovered ejection fraction (recEF) prognosis is unknown.

Purpose

To analyze characteristics and prognosis in patients with HFrEF (initial EF and at one year &lt;40%) and HFrecEF (initial EF &lt;40% and at one year ≥40% with ≥10% absolute improvement from the initial value).

Methods

Retrospective observational study of outpatients referred to the HF unit within March/2006 and November/2021. Baseline characteristics, ecocardiographic data and follow-up were collected, discerning between patients with HFrEF and HFrecEF.

Results

A total of 346 patients (76.0% men) were analyzed with a mean of age 66.3 (IQR 57.8–74.4) years, of which 50.6% remained with rEF and 49.4% recEF. Median follow-up was 4.6 (2.8–7.9) years. Both groups had a similar risk profile albeit less prevalence of dyslipidemia in the group with recEF (43.5% vs 56.7%, p=0.015). Ischemic etiology predominated in those with rEF (41.7% vs 25.7%, p=0.002) and enolic in recEF (10.5% vs 3.4%, p=0.009). The incidence of combined event (readmission for HF or death) was lower in HFrecEF (33.6% vs 66.4%, p&lt;0.001), as well as death (33.9% vs 66.1%, p&lt;0.001) and readmission for HF (24.4% vs 75.6%, p&lt;0.001). Prevalence of cardiovascular death was lower in the group with recEF (37.8% vs 61.1%, p=0.021). In the multivariate analysis, rEF was an independent predictor for the combined event (HR 2.17; 95% IC [1.45–3.25], p&lt;0.001), as well as for global mortality and readmission for HF.

Conclusion

Patients with HFrecEF have a similar risk profile than patients with HFrEF although with better long-term prognosis.

Funding Acknowledgement

Type of funding sources: None.

Association of Puberty Stage and Weight Status with Cardiometabolic Risk in Children and Adolescents Living on the Texas-Mexico Border

Background: This retrospective cohort study aimed to examine the interaction effect between puberty stage and weight status on individual and clustering of cardiometabolic risk factors (CMRFs) among Mexican American children and adolescents. A total of 333 children and adolescents (aged 8-18 years) enrolled in the Cameron County Hispanic Cohort (CCHC) from 2014 to 2020 were included in the study. Methods: CCHC is a longitudinal, randomly recruited cohort based on the United States Census tracts/blocks of Mexican Americans living on the Texas-Mexico border. Individual CMRFs, including high blood pressure, central obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol, and insulin resistance (IR) were assessed. Clustering of CMRFs is defined as the presence of three or more individual CMRFs. Puberty stages were assessed using the Tanner criteria. Multivariable logistic regressions were conducted to assess the association of puberty, weight status, and the interaction of the two main exposures with individual and clustering of CMRFs. Results: We observed that weight status had a dominant effect on all CMRF measures. The effect was especially prominent on central obesity and clustering of CMRFs. There were 95.4% of children with central obesity and 98.4% of those with clustering of CMRF were either overweight or obese. Entering puberty was associated with an increased risk of having IR [Tanner stage 2 vs. 1: odds ratio (OR) = 3.25, 95% confidence interval (95% CI) 1.28-8.27; Tanner stage 3 vs. 1: OR = 3.50, 95% CI 1.45-8.46] and hypertriglyceridemia (Tanner stage 2 vs. 1: OR = 2.67, 95% CI 1.11-6.45). However, the effects were not observed among those reaching the end of puberty (Tanner stage 4 and 5). Conclusions: A significant interaction effect between weight status and puberty was not detected on any individual CMRF and in the clustering of CMRFs. Other factors positively associated with individual CMRFs, especially IR, were being female and having a family history of diabetes.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

A Heterogeneous Iridium Catalyst for the Hydroboration of Pyridines

Sulfated zirconium oxide (SZO) capped with silylium-like ions reacts with (cod)Ir(py)Cl (cod = 1,5-cyclooctadiene; py = pyridine) to form [Ir(cod)py][SZO] (1) and Me₃SiCl. 1 can also be formed in reactions of phosphonium functionalized SZO and [Ir(cod)(OSi(O^tBu)₃]₂, which forms [Ir(cod)P(^tBu)₂Ph][SZO] (2), followed by reaction with pyridine to form 1. FTIR and ¹⁵N{¹H} MAS NMR spectroscopy are consistent with coordination of pyridine in 1 to an electrophilic iridium. 1 is moderately active in the dearomative hydroboration of pyridine. The primary product of this reaction is 1,2-dihydropyridine, which converts to the 1,4-dihydropyridine product at long reaction times. 1 catalyzes the dearomative hydroboration of a variety of substituted pyridines and is also reactive toward pyrazines and N-methylimidazole.

Cervical cancer prevention program in Nepal: A comprehensive "train the trainer" approach

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Background: Cervical cancer is the leading cause of cancer and cancer-related deaths among women in Nepal, due in part to a lack of access to screening and limited medical providers trained to diagnose and treat women with preinvasive cervical disease. Cancer Care Nepal has partnered with The University of Texas MD Anderson Cancer Center (MD Anderson) and the American Society of Clinical Oncology (ASCO) to implement a ‘train the trainer’ (TOT) program to teach visual inspection with acetic acid (VIA), colposcopy, cervical biopsy, cryotherapy, thermal ablation, and loop electrosurgical excision procedure (LEEP). Methods: An initial cervical cancer prevention course was held in Kathmandu, Nepal in November 2019, supported by ASCO and with faculty from Civil Service Hospital, Bhaktapur Cancer Hospital, and National Academy of Medical Sciences and MD Anderson. As a continuation of this program, a TOT course was implemented for local specialists from five participating institutions throughout Nepal to learn how to deliver these trainings. Each participating institution then holds their own local course for nurses and doctors in their region. The training is complemented with monthly Project ECHO (Extension for Community Healthcare Outcomes) telementoring videoconferences. Results: The program was launched in November 2021. To date, two TOT training courses (2-day duration) have been held for clinicians from the 5 participating regions. Due to COVID-19 pandemic travel restrictions, didactic lectures were held virtually with MD Anderson and ASCO staff and included epidemiology of cervical cancer, screening guidelines, colposcopy, and treatment of cervical dysplasia. This was followed by hands-on training using simulation models to teach VIA, colposcopy, ablation and LEEP, led by the Nepalese faculty who had participated in the 2019 course. There were 41 participants in total (23 in the first course and 18 in the second course), including 21 gynecologists, 4 gynecologic oncologists, 1 medical oncologist, 1 general practitioner, and 14 nurses. 39 participants (73%) completed both the pre- and post- survey results. 86% of respondents from the first course and 100% of respondents from the second course reported that they intended to change their practice as a result of knowledge gained from the course. In addition, Cancer Care Nepal became a new hub for Project ECHO and held its first session in January 2022, with 20 participants representing two regions. The specialists from each of the 5 participating sites will be holding local courses for doctors and nurses in their respective regions throughout 2022. Conclusions: Our work shows that the TOT strategy can widen the reach of training in cervical cancer prevention in Nepal. Despite travel restrictions during the COVID-19 pandemic, global health training and mentoring can continue, though they require adaptions and use of virtual platforms.

Clinical Correlates of Cardiac Conduction in Bipolar Disorder

Introduction

Patients with bipolar disorder (BD) have an increased risk for cardiovascular morbimortality. Clinical risk factors, specifically for arrhythmias and sudden cardiac death remain understudied.

Objectives

This study was conducted to assess differences in cardiac conduction among BD patients.

Methods

We included patients with BD in a cross-sectional design, confirmed by structured interview, age 18 through 80. Clinical characteristics were obtained using a structured questionnaire or medical records review. ECG intervals duration and morphology were manually assessed by cardiologists and compared among clinical subgroups using Chi-square, Mann-Whitney, and Kruskall-Wallis tests. Exploratory multivariable linear and logistic regression models were fitted to adjust for potential confounders.

Results

We included 117 patients (60.7% women, 76.9% bipolar I, 50% history of psychosis, 22.6% suicide attempts). We found a significantly longer QTc interval in BD patients with hypertension (difference: 9.5 ms, p=0.006), obesity (difference: 25 ms, p=0.001), and metabolic syndrome (difference: 13 ms, p=0.007). Hypertension remained a significant predictor of longer QTc after adjusting for age, gender, and antipsychotic use (estimate 17.718, p=0.018). We observed a significantly shorter PR interval in women (difference: 6 ms, p=0.029), early age of onset (difference 6 ms, p=0.025), non-users of lithium (difference 4 ms, p=0.002), and early trauma (difference 4 ms, p=0.038). Finally, we identified significant correlations between symptom severity, blood glucose and PR interval (r=0.298, p=0.001; r=0.278, p=0.003; respectively).

Conclusions

Patients with BD and hypertension may have an increased risk for QTc prolongation. Careful cardiovascular monitoring may be warranted.

Disclosure

No significant relationships.

OP0223 DISTINGUISHING OSTEOARTHRITIS AND RHEUMATOID ARTHRITIS SYNOVIUM WITH MACHINE LEARNING USING AUTOMATED CELL DENSITY AND PATHOLOGIST SCORES

Background

Joint damage in the knee can be severe in both rheumatoid arthritis (RA) and osteoarthritis (OA) such that total knee replacement (TKR) is often the only management option. Pathological assessment of the extent or type of synovial tissue inflammation from joint explants or biopsies can be useful. However, an ongoing challenge in using semi-quantitative assessments of synovitis is the disagreement between human pathologist scores of the same sample. We previously developed and validated a computer vision algorithm to automatically count each cell nucleus in an H&E-stained synovial whole slide image and yield a value of cell density, defined as mean nuclei count per mm2 of tissue1.

Objectives

We sought to develop methods to distinguish OA from RA based on machine learning analysis of histologic features on H&E-stained synovial tissue samples.

Methods

We measured 14 pathologist-scored histology features (137 RA and 152 OA patients) and computer vision quantified cell density (60 RA and 147 OA patients) in H&E stained synovial tissue samples from total knee replacement arthroplasty explants. A random forest model was trained using disease state (OA vs RA) as classifier and histology features and/or cell density as inputs, and feature importance scores for the model were calculated.

Results

Synovium from patients with RA exhibited increased lymphocytic inflammation, lining hyperplasia, neutrophils, detritus, plasma cells, Russell bodies, binucleate plasma cells, sub-lining giant cells, synovial lining giant cells, and fibrin (all p<0.001), while synovium from patients with OA had increased mast cells and fibrosis (both p<0.001). Fourteen pathologist-scored features allowed for discrimination between RA and OA samples, producing a macro-averaged area under the receiver operating curve (AUC) of 0.85. This discriminatory ability was comparable to that of the computer vision score of cell density alone (AUC = 0.88). Combining the pathologist scores with the cell density metric improved the discriminatory power of the model (AUC = 0.91). The three most important features in this combined model were mast cells followed by cell density and fibrosis (Figure 1). AUC values for each individual feature are provided in Table 1. The optimal cell density threshold to distinguish RA from OA synovium was 3,400 cells per mm2, which yielded a sensitivity of 0.82 and specificity of 0.82.

Table 1.

Area under receiver operating characteristic curves (AUC) of the synovial features in distinguishing RA and OA patients

FeatureAUCAutomated Cell Density0.88Fibrosis0.84Mast cells0.80Lining hyperplasia0.78Lymphocytic inflammation0.69Fibrin0.68Plasma cells0.66Detritus0.64Binucleate plasma cells0.60Neutrophils0.60Synovial giant cells0.58Sub-lining giant cells0.57Russell bodies0.56Germinal centers0.51Mucoid change0.50Figure 1.

Importance of synovial features in distinguishing RA and OA synovium

Feature importance scores for supervised machine learning model including all 14 pathology scores and the computer vision-generated cell density.

Conclusion

H&E-stained images of RA and OA TKR explant synovium are distinct. We identified cell density, mast cells and fibrosis as the three most important features for making this distinction, with RA being characterized by increased cell density, low mast cells, and low fibrosis. Cell density greater than 3400 per mm2 of tissue yields a sensitivity of 0.82 and a specificity of 0.82 for distinguishing RA from OA. In the future, this can have clinical and research applications as this technique removes the requirement for subjective selection of a certain field of interest, is reproducible, and is scalable as it does not require technical expertise of a pathologist.

References

[1]Guan S, Mehta B…Orange DE. Rheumatoid Arthritis Synovial Inflammation Quantification Using Computer Vision. ACR Open Rheumatology. 2022 Jan 10;acr2.11381.

Acknowledgements

This work was supported by the C. Ronald MacKenzie Young Scientist Endowment Award, the Leon Lowenstein Foundation, and the Kellen Scholar Award supported by the Anna Marie and Stephen Kellen Foundation Total Knee Improvement Program.

Disclosure of Interests

Bella Mehta Paid instructor for: Novartis, Susan Goodman Consultant of: UCB, Grant/research support from: Novartis, Edward DiCarlo: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, and Walgreens, J. Alex Gibbons: None declared, Miguel Otero Consultant of: Regeneron Pharmaceuticals, Grant/research support from: Tissue Genesis, Laura Donlin Speakers bureau: Stryker, Consultant of: Stryker, Grant/research support from: Karius, Inc, Tania Pannellini: None declared, William Robinson: None declared, Peter Sculco Consultant of: Intellijoint Surgical, DePuy Synthes, Lima Corporate, Zimmer Biomet, and EOS Imaging, Grant/research support from: Intellijoint Surgical and Zimmer Biomet, Mark Figgie Shareholder of: HS2, Mekanika, and Wishbone, Consultant of: Lima and Wishbone, Jose Rodriguez Consultant of: ConforMIS, Medacta, Exactech, Inc, and Smith & Nephew, Grant/research support from: DePuy, Exactech, Inc, and Smith & Nephew, Jessica Kirschmann: None declared, James Thompson: None declared, David Slater: None declared, Damon Frezza: None declared, Zhenxing Xu: None declared, Fei Wang: None declared, Dana Orange: None declared

Epitope-focused immunogen design based on the ebolavirus glycoprotein HR2-MPER region

The three human pathogenic ebolaviruses: Zaire (EBOV), Bundibugyo (BDBV), and Sudan (SUDV) virus, cause severe disease with high fatality rates. Epitopes of ebolavirus glycoprotein (GP) recognized by antibodies with binding breadth for all three ebolaviruses are of major interest for rational vaccine design. In particular, the heptad repeat 2 -membrane-proximal external region (HR2-MPER) epitope is relatively conserved between EBOV, BDBV, and SUDV GP and targeted by human broadly-neutralizing antibodies. To study whether this epitope can serve as an immunogen for the elicitation of broadly-reactive antibody responses, protein design in Rosetta was employed to transplant the HR2-MPER epitope identified from a co-crystal structure with the known broadly-reactive monoclonal antibody (mAb) BDBV223 onto smaller scaffold proteins. From computational analysis, selected immunogen designs were produced as recombinant proteins and functionally validated, leading to the identification of a sterile alpha motif (SAM) domain displaying the BDBV-HR2-MPER epitope near its C terminus as a promising candidate. The immunogen was fused to one component of a self-assembling, two-component nanoparticle and tested for immunogenicity in rabbits. Robust titers of cross-reactive serum antibodies to BDBV and EBOV GPs and moderate titers to SUDV GP were induced following immunization. To confirm the structural composition of the immunogens, solution NMR studies were conducted and revealed structural flexibility in the C-terminal residues of the epitope. Overall, our study represents the first report on an epitope-focused immunogen design based on the structurally challenging BDBV-HR2-MPER epitope.

Dietary Postbiotics Reduce Cytotoxicity and Inflammation Induced by Crystalline Silica in an In Vitro RAW 264.7 Macrophage Model

Crystalline silica (cSiO₂) particles are naturally existing environmental toxicants. Exposure to cSiO₂ could cause local or systemic inflammation and aggregate inflammation-associated diseases. Dietary postbiotics are reported to possess anti-inflammatory activities; however, their effects on cSiO₂-triggered inflammation are unknown. Here, we investigate the impact of postbiotics from Lacticaseibacillus rhamnosus (LGG), Limosilactobacillus reuteri (L.reu), and Bifidobacterium animalis subsp. lactis Bb12 (BB12) on cSiO₂-induced cytotoxicity and IL-1 cytokines in vitro using macrophages. The postbiotics used in this study were cell-free fractions of a probiotic growth medium collected at different time points. The in vitro model used was the wild-type murine macrophage RAW 264.7 cell line stably transfected with the inflammasome adapter protein, ASC. Our results indicate that all the postbiotics could reduce cSiO₂-induced cytotoxicity in the wild-type and ASC macrophages and the effects were OD-dependent. Following priming with a lipopolysaccharide, cSiO₂ treatment resulted in robust inflammasome activation in ASC, as reflected by the IL-1β release. These responses were minimal or absent in the wild-type RAW cells. All the postbiotics decreased the release of IL-1β from ASC; however, only LGG and BB12 reduced the IL-1β secretion from wild-type cells. Only the L.reu postbiotics reduced the IL-1α release from ASC. We conclude that the postbiotics from LGG, BB12, and L.reu can protect macrophages against cSiO₂-induced cytotoxicity and suppress IL-1β activation.

Human Monoclonal Antibodies against NS1 Protein Protect against Lethal West Nile Virus Infection

Envelope protein-targeted vaccines for flaviviruses are limited by concerns of antibody-dependent enhancement (ADE) of infections. Nonstructural protein 1 (NS1) provides an alternative vaccine target that avoids this risk since this protein is absent from the virion. Beyond its intracellular role in virus replication, extracellular forms of NS1 function in immune modulation and are recognized by host-derived antibodies. The rational design of NS1-based vaccines requires an extensive understanding of the antigenic sites on NS1, especially those targeted by protective antibodies. Here, we isolated human monoclonal antibodies (MAbs) from individuals previously naturally infected with WNV, mapped their epitopes using structure-guided mutagenesis, and evaluated their efficacy in vivo against lethal WNV challenge. The most protective epitopes clustered at three antigenic sites that are exposed on cell surface forms of NS1: (i) the wing flexible loop, (ii) the outer, electrostatic surface of the wing, and (iii) the spaghetti loop face of the β-ladder. One additional MAb mapped to the distal tip of the β-ladder and conferred a lower level of protection against WNV despite not binding to NS1 on the surface of infected cells. Our study defines the epitopes and modes of binding of protective anti-NS1 MAb antibodies following WNV infection, which may inform the development of NS1-based countermeasures against flaviviruses. IMPORTANCE Therapeutic antibodies against flaviviruses often promote neutralization by targeting the envelope protein of the virion. However, this approach is hindered by a possible concern for antibody-dependent enhancement of infection and paradoxical worsening of disease. As an alternative strategy, antibodies targeting flavivirus nonstructural protein 1 (NS1), which is absent from the virion, can protect against disease and do not cause enhanced infection. Here, we evaluate the structure-function relationships and protective activity of West Nile virus (WNV) NS1-specific monoclonal antibodies (MAbs) isolated from the memory B cells of a naturally infected human donor. We identify several anti-NS1 MAbs that protect mice against lethal WNV challenge and map their epitopes using charge reversal mutagenesis. Antibodies targeting specific regions in the NS1 structure could serve as the basis for countermeasures that control WNV infection in humans.

Left atrial appendage perimeter ostium evaluation by cardiac CT utilizing 3mensio technology for watchman implantation

Background

Left atrial appendage occlusion (LAAO) with Watchman device traditionally relies on accurate left atrial appendage ostium diameter measurement by 2D or 3D transesophageal echocardiogram (TEE). Alternate methods of ostium measurement including area-derived diameter and perimeter-derived diameter using cardiac computed tomography (CT) have been proposed.

Methods

We performed a retrospective analysis of 92 patients with atrial fibrillation (Afib) who underwent LAAO with WATCHMAN implantation with pre-procedural TEE and CT between May 2015 and December 2018. LAA characteristics including ostial or landing zone perimeter, minimum and maximum diameters were acquired utilizing 3mensio Structural Heart Imaging Program. Proposed device size was estimated utilizing ostium perimeter by CT and compared to the current standard utilizing ostium diameter by 2D-TEE. Both measurements were then compared to actual final device size that satisfying release criteria.

Results

CT had a very high correlation with the actual implanted device size (Pearson coefficient r=0.94, p&lt;0.001), while TEE based sizing had a lower correlation (Pearson coefficient r=0.66, p&lt;0.001). CT predicted size had a significantly higher agreement compared to standard TEE based sizing (93.4% vs 47.8%), and higher interrater agreement (Cohen's kappa = 0.91 vs Cohen's kappa = 0.32, p&lt;0.001, p&lt;0.001 respectively). Bland-Altman analysis also showed better correlation with CT-based sizing. Procedural complications were 0, and 0 patients had a leak recorded at 45-days post implant.

Conclusion

CCT LAA perimeter sizing is superior to the current standard TEE based Watchman sizing. Larger, multi-center studies may be necessary to further validate results.

Funding Acknowledgement

Type of funding sources: None. 3mensio after CT upload

5-Aminolevulinic acid for enhanced surgical visualization of high-grade gliomas: a prospective, multicenter study

OBJECTIVE

Greater extent of resection (EOR) is associated with longer overall survival in patients with high-grade gliomas (HGGs). 5-Aminolevulinic acid (5-ALA) can increase EOR by improving intraoperative visualization of contrast-enhancing tumor during fluorescence-guided surgery (FGS). When administered orally, 5-ALA is converted by glioma cells into protoporphyrin IX (PPIX), which fluoresces under blue 400-nm light. 5-ALA has been available for use in Europe since 2010, but only recently gained FDA approval as an intraoperative imaging agent for HGG tissue. In this first-ever, to the authors' knowledge, multicenter 5-ALA FGS study conducted in the United States, the primary objectives were the following: 1) assess the diagnostic accuracy of 5-ALA-induced PPIX fluorescence for HGG histopathology across diverse centers and surgeons; and 2) assess the safety profile of 5-ALA FGS, with particular attention to neurological morbidity.

METHODS

This single-arm, multicenter, prospective study included adults aged 18-80 years with Karnofsky Performance Status (KPS) score > 60 and an MRI diagnosis of suspected new or recurrent resectable HGG. Intraoperatively, 3-5 samples per tumor were taken and their fluorescence status was recorded by the surgeon. Specimens were submitted for histopathological analysis. Patients were followed for 6 weeks postoperatively for adverse events, changes in the neurological exam, and KPS score. Multivariate analyses were performed of the outcomes of KPS decline, EOR, and residual enhancing tumor volume to identify predictive patient and intraoperative variables.

RESULTS

Sixty-nine patients underwent 5-ALA FGS, providing 275 tumor samples for analysis. PPIX fluorescence had a sensitivity of 96.5%, specificity of 29.4%, positive predictive value (PPV) for HGG histopathology of 95.4%, and diagnostic accuracy of 92.4%. Drug-related adverse events occurred at a rate of 22%. Serious adverse events due to intraoperative neurological injury, which may have resulted from FGS, occurred at a rate of 4.3%. There were 2 deaths unrelated to FGS. Compared to preoperative KPS scores, postoperative KPS scores were significantly lower at 48 hours and 2 weeks but were not different at 6 weeks postoperatively. Complete resection of enhancing tumor occurred in 51.9% of patients. Smaller preoperative tumor volume and use of intraoperative MRI predicted lower residual tumor volume.

CONCLUSIONS

PPIX fluorescence, as judged by the surgeon, has a high sensitivity and PPV for HGG. 5-ALA was well tolerated in terms of drug-related adverse events, and its application by trained surgeons in FGS for HGGs was not associated with any excess neurological morbidity.

Genetic and structural basis for SARS-CoV-2 variant neutralization by a two-antibody cocktail

Understanding the molecular basis for immune recognition of SARS-CoV-2 spike glycoprotein antigenic sites will inform the development of improved therapeutics. We determined the structures of two human monoclonal antibodies-AZD8895 and AZD1061-which form the basis of the investigational antibody cocktail AZD7442, in complex with the receptor-binding domain (RBD) of SARS-CoV-2 to define the genetic and structural basis of neutralization. AZD8895 forms an 'aromatic cage' at the heavy/light chain interface using germ line-encoded residues in complementarity-determining regions (CDRs) 2 and 3 of the heavy chain and CDRs 1 and 3 of the light chain. These structural features explain why highly similar antibodies (public clonotypes) have been isolated from multiple individuals. AZD1061 has an unusually long LCDR1; the HCDR3 makes interactions with the opposite face of the RBD from that of AZD8895. Using deep mutational scanning and neutralization escape selection experiments, we comprehensively mapped the crucial binding residues of both antibodies and identified positions of concern with regards to virus escape from antibody-mediated neutralization. Both AZD8895 and AZD1061 have strong neutralizing activity against SARS-CoV-2 and variants of concern with antigenic substitutions in the RBD. We conclude that germ line-encoded antibody features enable recognition of the SARS-CoV-2 spike RBD and demonstrate the utility of the cocktail AZD7442 in neutralizing emerging variant viruses.

Convergent antibody responses to the SARS-CoV-2 spike protein in convalescent and vaccinated individuals

Unrelated individuals can produce genetically similar clones of antibodies, known as public clonotypes, which have been seen in responses to different infectious diseases, as well as healthy individuals. Here we identify 37 public clonotypes in memory B cells from convalescent survivors of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or in plasmablasts from an individual after vaccination with mRNA-encoded spike protein. We identify 29 public clonotypes, including clones recognizing the receptor-binding domain (RBD) in the spike protein S1 subunit (including a neutralizing, angiotensin-converting enzyme 2 [ACE2]-blocking clone that protects in vivo) and others recognizing non-RBD epitopes that bind the S2 domain. Germline-revertant forms of some public clonotypes bind efficiently to spike protein, suggesting these common germline-encoded antibodies are preconfigured for avid recognition. Identification of large numbers of public clonotypes provides insight into the molecular basis of efficacy of SARS-CoV-2 vaccines and sheds light on the immune pressures driving the selection of common viral escape mutants.

Therapeutic alphavirus cross-reactive E1 human antibodies inhibit viral egress

Alphaviruses cause severe arthritogenic or encephalitic disease. The E1 structural glycoprotein is highly conserved in these viruses and mediates viral fusion with host cells. However, the role of antibody responses to the E1 protein in immunity is poorly understood. We isolated E1-specific human monoclonal antibodies (mAbs) with diverse patterns of recognition for alphaviruses (ranging from Eastern equine encephalitis virus [EEEV]-specific to alphavirus cross-reactive) from survivors of natural EEEV infection. Antibody binding patterns and epitope mapping experiments identified differences in E1 reactivity based on exposure of epitopes on the glycoprotein through pH-dependent mechanisms or presentation on the cell surface prior to virus egress. Therapeutic efficacy in vivo of these mAbs corresponded with potency of virus egress inhibition in vitro and did not require Fc-mediated effector functions for treatment against subcutaneous EEEV challenge. These studies reveal the molecular basis for broad and protective antibody responses to alphavirus E1 proteins.

Nucleophilic Addition to π-Allyl Gold(III) Complexes: Evidence for Direct and Undirect Paths

π-Allyl complexes play a prominent role in organometallic chemistry and have attracted considerable attention, in particular the π-allyl Pd(II) complexes which are key intermediates in the Tsuji-Trost allylic substitution reaction. Despite the huge interest in π-complexes of gold, π-allyl Au(III) complexes were only authenticated very recently. Herein, we report the reactivity of (P,C)-cyclometalated Au(III) π-allyl complexes toward β-diketo enolates. Behind an apparently trivial outcome, i.e. the formation of the corresponding allylation products, meticulous NMR studies combined with DFT calculations revealed a complex and rich mechanistic picture. Nucleophilic attack can occur at the central and terminal positions of the π-allyl as well as the metal itself. All paths are observed and are actually competitive, whereas addition to the terminal positions largely prevails for Pd(II). Auracyclobutanes and π-alkene Au(I) complexes were authenticated spectroscopically and crystallographically, and Au(III) σ-allyl complexes were unambiguously characterized by multinuclear NMR spectroscopy. Nucleophilic additions to the central position of the π-allyl and to gold are reversible. Over time, the auracyclobutanes and the Au(III) σ-allyl complexes evolve into the π-alkene Au(I) complexes and release the C-allylation products. The relevance of auracyclobutanes in gold-mediated cyclopropanation was demonstrated by inducing C-C coupling with iodine. The molecular orbitals of the π-allyl Au(III) complexes were analyzed in-depth, and the reaction profiles for the addition of β-diketo enolates were thoroughly studied by DFT. Special attention was devoted to the regioselectivity of the nucleophilic attack, but C-C coupling to give the allylation products was also considered to give a complete picture of the reaction progress.

Ethylene Polymerization Activity of (R3P)Ni(codH)+ (cod = 1,5-cylcooctadiene) Sites Supported on Sulfated Zirconium Oxide

PAr₃ containing o-OMe, o-Me, or o-Et substituents reacts with Brønsted sites on sulfated zirconium oxide (SZO) to form [HPAr₃][SZO]. The phosphonium sites on this material react with bis(cyclooctadiene)nickel [Ni(cod)₂] to form [Ni(PAr₃)(codH)][SZO] that are active in ethylene polymerization reactions. Selective poisoning studies with pyridine show that ∼90% of the Ni(PAr₃)(codH)⁺ sites in this material are active in polymerization reactions.

Increased Cuticle Waxes by Overexpression of WSD1 Improves Osmotic Stress Tolerance in Arabidopsis thaliana and Camelina sativa

To ensure global food security under the changing climate, there is a strong need for developing ‘climate resilient crops’ that can thrive and produce better yields under extreme environmental conditions such as drought, salinity, and high temperature. To enhance plant productivity under the adverse conditions, we constitutively overexpressed a bifunctional wax synthase/acyl-CoA:diacylglycerol acyltransferase (WSD1) gene, which plays a critical role in wax ester synthesis in Arabidopsis stem and leaf tissues. The qRT-PCR analysis showed a strong upregulation of WSD1 transcripts by mannitol, NaCl, and abscisic acid (ABA) treatments, particularly in Arabidopsis thaliana shoots. Gas chromatography and electron microscopy analyses of Arabidopsis seedlings overexpressing WSD1 showed higher deposition of epicuticular wax crystals and increased leaf and stem wax loading in WSD1 transgenics compared to wildtype (WT) plants. WSD1 transgenics exhibited enhanced tolerance to ABA, mannitol, drought and salinity, which suggested new physiological roles for WSD1 in stress response aside from its wax synthase activity. Transgenic plants were able to recover from drought and salinity better than the WT plants. Furthermore, transgenics showed reduced cuticular transpirational rates and cuticle permeability, as well as less chlorophyll leaching than the WT. The knowledge from Arabidopsis was translated to the oilseed crop Camelina sativa (L.) Crantz. Similar to Arabidopsis, transgenic Camelina lines overexpressing WSD1 also showed enhanced tolerance to drought stress. Our results clearly show that the manipulation of cuticular waxes will be advantageous for enhancing plant productivity under a changing climate.

Convergent antibody responses to the SARS-CoV-2 spike protein in convalescent and vaccinated individuals

Unrelated individuals can produce genetically similar clones of antibodies, known as public clonotypes, which have been seen in responses to different infectious diseases as well as healthy individuals. Here we identify 37 public clonotypes in memory B cells from convalescent survivors of SARS-CoV-2 infection or in plasmablasts from an individual after vaccination with mRNA-encoded spike protein. We identified 29 public clonotypes, including clones recognizing the receptor-binding domain (RBD) in the spike protein S1 subunit (including a neutralizing, ACE2-blocking clone that protects in vivo ), and others recognizing non-RBD epitopes that bound the heptad repeat 1 region of the S2 domain. Germline-revertant forms of some public clonotypes bound efficiently to spike protein, suggesting these common germline-encoded antibodies are preconfigured for avid recognition. Identification of large numbers of public clonotypes provides insight into the molecular basis of efficacy of SARS-CoV-2 vaccines and sheds light on the immune pressures driving the selection of common viral escape mutants.

Oxidative additions of alkynyl/vinyl iodides to gold and gold-catalyzed vinylation reactions triggered by the MeDalphos ligand

The hemilabile Ad2P(o-C6H4)NMe2 ligand promotes fast, quantitative and irreversible oxidative addition of alkynyl and vinyl iodides to gold. The reaction is general. It works with a broad range of substrates of various electronic bias and steric demand, and proceeds with complete retention of stereochemistry from Z and E vinyl iodides. Both alkynyl and vinyl iodides react faster than aryl iodides. The elementary step is amenable to catalysis. Oxidative addition of vinyl iodides to gold and π-activation of alkenols (and N-alkenyl amines) at gold have been combined to achieve hetero-vinylation reactions. A number of functionalized heterocycles, i.e. tetrahydrofuranes, tetrahydropyranes, oxepanes and pyrrolidines were obtained thereby (24 examples, 87% average yield). Taking advantage of the chemoselectivity for vinyl iodides over aryl iodides, sequential transformations involving first a hetero-vinylation step and then a C-N coupling, a C-C coupling or an heteroarylation were achieved from a vinyl/aryl bis-iodide substrate.

Potent neutralization of Rift Valley fever virus by human monoclonal antibodies through fusion inhibition

Rift Valley fever virus (RVFV), an emerging arboviral and zoonotic bunyavirus, causes severe disease in livestock and humans. Here, we report the isolation of a panel of monoclonal antibodies (mAbs) from the B cells of immune individuals following natural infection in Kenya or immunization with MP-12 vaccine. The B cell responses of individuals who were vaccinated or naturally infected recognized similar epitopes on both Gc and Gn proteins. The Gn-specific mAbs and two mAbs that do not recognize either monomeric Gc or Gn alone but recognized the hetero-oligomer glycoprotein complex (Gc+Gn) when Gc and Gn were coexpressed exhibited potent neutralizing activities in vitro, while Gc-specific mAbs exhibited relatively lower neutralizing capacity. The two Gc+Gn-specific mAbs and the Gn domain A-specific mAbs inhibited RVFV fusion to cells, suggesting that mAbs can inhibit the exposure of the fusion loop in Gc, a class II fusion protein, and thus prevent fusion by an indirect mechanism without direct fusion loop contact. Competition-binding analysis with coexpressed Gc/Gn and mutagenesis library screening indicated that these mAbs recognize four major antigenic sites, with two sites of vulnerability for neutralization on Gn. In experimental models of infection in mice, representative mAbs recognizing three of the antigenic sites reduced morbidity and mortality when used at a low dose in both prophylactic and therapeutic settings. This study identifies multiple candidate mAbs that may be suitable for use in humans against RVFV infection and highlights fusion inhibition against bunyaviruses as a potential contributor to potent antibody-mediated neutralization.