Live-cell imaging unveils distinct R-loop populations with heterogeneous dynamics.

We have developed RHINO, a genetically encoded sensor that selectively binds RNA:DNA hybrids enabling live-cell imaging of cellular R-loops. RHINO comprises a tandem array of three copies of the RNA:DNA hybrid binding domain of human RNase H1 connected by optimized linker segments and fused to a fluorescent protein. This tool allows the measurement of R-loop abundance and dynamics in live cells with high specificity and sensitivity. Using RHINO, we provide a kinetic framework for R-loops at nucleoli, telomeres and protein-coding genes. Our findings demonstrate that R-loop dynamics vary significantly across these regions, potentially reflecting the distinct roles R-loops play in different chromosomal contexts. RHINO is a powerful tool for investigating the role of R-loops in cellular processes and their contribution to disease development and progression.

Racial and Ethnic Disparities in Operative Experience Among General Surgery Residents: A Multi-Institutional Study from the US ROPE Consortium.

OBJECTIVE: To determine the relationship between race/ethnicity and case volume among graduating surgical residents. BACKGROUND: Racial/ethnic minority individuals face barriers to entry and advancement in surgery; however, no large-scale investigations of the operative experience of racial/ethnic minority residents have been performed. METHODS: A multi-institutional retrospective analysis of the Accreditation Council for Graduate Medical Education case logs of categorical general surgery residents at 20 programs in the US Resident OPerative Experience Consortium database was performed. All residents graduating between 2010 and 2020 were included. The total, surgeon chief, surgeon junior, and teaching assistant case volumes were compared between racial/ethnic groups. RESULTS: The cohort included 1343 residents. There were 211 (15.7%) Asian, 65 (4.8%) Black, 73 (5.4%) Hispanic, 71 (5.3%) "Other" (Native American or Multiple Race), and 923 (68.7%) White residents. On adjusted analysis, Black residents performed 76 fewer total cases (95% CI, -109 to -43, P <0.001) and 69 fewer surgeon junior cases (-98 to -40, P <0.001) than White residents. Comparing adjusted total case volume by graduation year, both Black residents and White residents performed more cases over time; however, there was no difference in the rates of annual increase (10 versus 12 cases per year increase, respectively, P =0.769). Thus, differences in total case volume persisted over the study period. CONCLUSIONS: In this multi-institutional study, Black residents graduated with lower case volume than non-minority residents throughout the previous decade. Reduced operative learning opportunities may negatively impact professional advancement. Systemic interventions are needed to promote equitable operative experience and positive culture change.

BELB: a biomedical entity linking benchmark.

MOTIVATION: Biomedical entity linking (BEL) is the task of grounding entity mentions to a knowledge base (KB). It plays a vital role in information extraction pipelines for the life sciences literature. We review recent work in the field and find that, as the task is absent from existing benchmarks for biomedical text mining, different studies adopt different experimental setups making comparisons based on published numbers problematic. Furthermore, neural systems are tested primarily on instances linked to the broad coverage KB UMLS, leaving their performance to more specialized ones, e.g. genes or variants, understudied. RESULTS: We therefore developed BELB, a biomedical entity linking benchmark, providing access in a unified format to 11 corpora linked to 7 KBs and spanning six entity types: gene, disease, chemical, species, cell line, and variant. BELB greatly reduces preprocessing overhead in testing BEL systems on multiple corpora offering a standardized testbed for reproducible experiments. Using BELB, we perform an extensive evaluation of six rule-based entity-specific systems and three recent neural approaches leveraging pre-trained language models. Our results reveal a mixed picture showing that neural approaches fail to perform consistently across entity types, highlighting the need of further studies towards entity-agnostic models. AVAILABILITY AND IMPLEMENTATION: The source code of BELB is available at: https://github.com/sg-wbi/belb. The code to reproduce our experiments can be found at: https://github.com/sg-wbi/belb-exp.

Observed Changes in the Distribution of Colon Cancer Metastasis: A National Cancer Database Review and Institutional Experience.

BACKGROUND: The University of Louisville has observed a near 70% drop in resectable/borderline resectable metastatic colorectal cancer in the past 5 years. The aim of this study was to evaluate the distribution of colon cancer metastasis at diagnosis and at recurrence. PATIENTS AND METHODS: Stage was defined by the American joint committee on cancer (AJCC) eighth edition. Institutional review board approval was granted for post hoc review of stage II and III patients with colon cancer from the University of Louisville prospective hepatic database from 2002 to 2023, as well as for the National cancer database (NCDB) Participant user file (PUF) 2021. The Surveillance epidemiology and end-results (SEER) 22 database was also utilized to corroborate the findings in the NCDB. RESULTS: Between 2018 and 2021 pathological M1a decreased annually (51.9-46.3%), while M1c increased year-over-year (26.6-32.4%) and M1b stayed relatively the same (21.4-21.3%). These differences were significant on chi-squared analysis with a p value of < 0.001. Univariate analysis of the post hoc review between 2017 and 2020 revealed significant differences between stage 4a and 4c in terms of race (p value 0.018), carcinoembryonic antigen (CEA) at diagnosis (p value 0.037), CEA at recurrence (p value 0.012), presence of liver metastasis (p value 0.003), and referral pattern (p value 0.014). Multivariate analysis identified stage 4b as an independent predictor for hepatic metastasis (odds ratio; OR 4.69, p value 0.011). CONCLUSIONS: A significant change in the distribution of colon cancer metastases has occurred at an institutional and national level over the past 3-5 years. Interdisciplinary treatment strategies will have to be modified accordingly.

Interval Sentinel Lymph Nodes With the Use of Routine Lymphoscintigraphy in Extremity Melanoma.

INTRODUCTION: Lymphoscintigraphy (LS) helps identify drainage to interval (epitrochlear or popliteal) lymph node basins for extremity melanomas. This study evaluated how often routine LS evaluation identified an interval sentinel lymph node (SLN) and how often that node was found to have metastasis. METHODS: A single institution, retrospective study identified patients with an extremity melanoma who underwent routine LS and SLN biopsy over a 25-y period. Comparisons of factors associated with the identification of interval node drainage and tumor status were made. RESULTS: In 634 patients reviewed, 5.7% of patients drained to an interval SLN. Of those biopsied, 29.2% were positive for micrometastases. Among patients with biopsies of both the traditional and interval nodal basins, nearly 20% had positive interval nodes with negative SLNs in the traditional basin. Sex, age, thickness, ulceration, and the presence of mitotic figures were not predictive of identifying an interval node on LS, nor for having disease in an interval node. Anatomic location of the primary melanoma was the only identifiable risk factor, as no interval nodes were identified in melanomas of the thigh or upper arm (P ≤ 0.001). CONCLUSIONS: Distal extremity melanomas have a moderate risk of mapping to an interval SLN. Routine LS should be considered in these patients, especially as these may be the only tumor-positive nodes. However, primary extremity melanomas proximal to the epitrochlear or popliteal nodal basins do not map to interval nodes, and improved savings and workflow could be realized by selectively omitting routine LS in such patients.

Changes in Incidence of Cirrhotic and Noncirrhotic Hepatocellular Carcinoma in the United States.

INTRODUCTION: Hepatocellular carcinoma (HCC) occurs most often in a background of cirrhosis. Patients with noncirrhotic HCC represent a distinct population, which has been characterized in single-center studies, but has not been fully evaluated on a population level in the United States. MATERIALS AND METHODS: HCC cases from Surveillance, Epidemiology, and End-Results diagnosed between 2000 and 2020 were categorized as cirrhotic or noncirrhotic. Clinical and pathologic factors, age-adjusted incidence rates (AAIR), and the overall HCC-specific survival were compared between groups. RESULTS: There were 18,592 patients with cirrhosis (80.4%) and 4545 without (19.6%). AAIRs for noncirrhotic HCC remained relatively unchanged from 2010 to 2020, with a mean incidence of 0.35 per 100,000. The AAIR for cirrhotic HCC declined from 1.59 to 0.85 per 100,000 during the same period. Patients with cirrhosis were younger (median age 62 versus 65 y, P < 0.001). Patients without cirrhosis, compared to those with cirrhosis, were less likely to have elevated alpha fetoprotein (53.9% versus 62.0%, P < 0.001), had larger tumors (median tumor size 5.0 versus 3.5 cm, P < 0.001), presented more frequently with localized disease (59.9% versus 55.8%, P < 0.001), were more likely to undergo surgery (OR 2.21, 95% CI 2.07-2.36), and had better HCC-specific survival (median 40 versus 27 mo, P < 0.001). CONCLUSIONS: The relative increase in the proportion of noncirrhotic HCC in the Untied States may be due to a decline in the incidence of cirrhotic HCC. Patients with noncirrhotic HCC have larger tumors, are more likely to undergo surgical resection, and have improved cancer-specific survival.

Barriers to resection following neoadjuvant chemotherapy for resectable pancreatic adenocarcinoma: A national and local perspective.

BACKGROUND: Neoadjuvant chemotherapy (NAC) use for pancreatic ductal adenocarcinoma (PDAC) has increased, but some patients never get resection following NAC. METHODS: Data from January 2012 to December 2019 for all clinically resectable patients across two health networks were utilized, as well as data from the ACS NCDB registry. Univariate testing, multivariable logistic regression, and survival analyses were employed to evaluate failure to resection after neo-adjuvant chemotherapy. RESULTS: Of the 10 007 registry patients eligible for resection, the resected group was younger (64.6 vs. 69.5 years; p < 0.001) and had a slightly lower mean comorbidity index (0.41 vs. 0.45; p < 0.001) than the nonsurgical group. The nonsurgical group was composed of a higher percentage of Black and Hispanic patients (17.5 vs. 13.1%; p < 0.001). After adjusting for age and comorbidities, the factors associated with decreased probability of resection after NAC were evaluation at a community hospital (OR 2.4), Black or Hispanic race (OR 1.6), areas of increased high school drop-out rates (OR 1.4), and lack of private health insurance (OR 1.3). The median overall survival for nonsurgery was markedly worse than the surgical cohort (10.6 vs. 26.6 months; p < 0.001). The most frequent reasons for a lack of definitive resection were operative upstaging to unresectable (39.6%), patient preference (14.5%), progression on NAC (13.2%), deconditioning or comorbidity severity (12.5%), and nonreferral to a surgeon (8.8%). CONCLUSIONS: Racial, economic, and educational disparities have a considerable influence on the successful completion of a neoadjuvant approach for resectable PDAC. A comprehensive closed or highly collaborative/communicative multidisciplinary neoadjuvant program is optimal for treatment success and completion.

Complete genome sequence of vaccinium-associated virus C, a new member of the family Totiviridae from Vaccinium floribundum.

Blueberries (Vaccinium sp.) are a major crop grown in the Pacific Northwest region. Currently, there are at least 17 known viruses that infect blueberry plants, and some of them cause a wide range of symptoms and economic losses. A new virus, vaccinium-associated virus C (VaVC) (family Totiviridae, genus Totivirus) was identified in an imported blueberry accession from the USDA-ARS National Clonal Germplasm Repository in Corvallis, Oregon. The complete genomic sequence of VaVC was determined, but the biological significance of VaVC is unknown and requires further study. Additional Vaccinium sp. accessions should be screened to investigate the incidence of this new virus.

Simultaneous mapping of cathodoluminescence spectra and backscatter diffraction patterns in a scanning electron microscope.

Electron backscatter diffraction and cathodoluminescence are complementary scanning electron microscopy modes widely used in the characterisation of semiconductor films, respectively revealing the strain state of a crystalline material and the effect of this strain on the light emission from the sample. Conflicting beam, sample and detector geometries have meant it is not generally possible to acquire the two signals together during the same scan. Here, we present a method of achieving this simultaneous acquisition, by collecting the light emission through a transparent sample substrate. We apply this combination of techniques to investigate the strain field and resultant emission wavelength variation in a deep-ultraviolet micro-LED. For such compatible samples, this approach has the benefits of avoiding image alignment issues and minimising beam damage effects.

Combined pre-operative risk score predicts pancreatic leak after pancreatic resection.

BACKGROUND: Post-operative pancreatic fistula (POPF) is a major complication following pancreatectomy and is currently difficult to predict pre-operatively. This study aims to validate pre-operative risk factors and develop a novel combined score for the prediction of POPF in the pre-operative setting. METHODS: Data were collected from 2016 to 2021 for radiologic main pancreatic duct diameter (MPD), body mass index (BMI), physical status classified by American Society of Anesthesiologists (ASA), polypharmacy, mean platelet ratio (MPR), comorbidity-polypharmacy score (CPS), and a novel Combined Pancreatic Leak Prediction Score (CPLPS) (derived from MPD diameter, BMI, and CPS) were obtained from pre-operative data and analyzed for their independent association with POPF occurrence. RESULTS: In total, 166 patients who underwent pancreatectomy with pancreatic leak (Grade A, B, and C) occurring in 51(30.7%) of patients. Pre-operative radiologic MPD diameter < 4 mm (p < 0.001), < 5 mm (p < 0.001), < 6 mm (p = 0.001), BMI ≥ 25 (p = 0.009), and ≥ 30 (p = 0.017) were independently associated with the occurrence of pancreatic leak. CPLPS was also predictive of pancreatic leak following pancreatectomy on univariate (p = 0.005) and multivariate analysis (p = 0.036). CONCLUSION: MPD and BMI were independent risk factors predictive for the development of pancreatic leak. CPLPS, was an independent predictor of pancreatic leak following pancreatectomy and could be used to help guide surgical decision making and patient counseling.

Thermal ablation enhances immunotherapeutic effect of IP-001 on orthotopic liver cancer in a rat model.

BACKGROUND: Thermal ablation is reported to increase immunogenicity in tumor cells via expressing tumor antigens. IP-001, a synthesized molecule, is created by attaching galactose molecules to the free amino groups of partially deacetylated glucosamine polymers. As a member of a new class of polycationic immunoadjuvants that activate multiple immune response pathways, IP-001 can both sequester ablation-released tumor antigens in situ and independently recruit and stimulate antigen presenting cells (APCs) to induce a potent tumor-specific Th1 type T cell response. METHODS: An orthotopic HCC rat model is established by implantation of 5 × 106 N1-S1 cells into the left lobe of liver. When tumor size reached 1.0-1.5 cm3, the animals were divided randomly into 4 groups, (1) MWA+IP-001; (2) MWA+saline; (3) sham MWA+IP-001 and (4) sham MWA+saline (n = 5 each group). RESULTS: IP001 + MWA treatment significantly suppressed tumor growth in comparison to the other 3 groups. Significantly increased infiltration of inflammatory/immune cells were found in the tumor adjacent tissues of MWA+IP-001 mice, compared to the other 3 groups. Flow cytometry results indicated that there were significant increases of cytotoxic T cells, macrophages, dendritic cells and NK cell in the combination of MWA and IP001 treated mice, compared to other 3 groups (p < 0.01). Significantly decreased number of Treg cells were found in all the treatment arms compared to untreated control (p < 0.01). CONCLUSION: Combination of MWA and IP001 enhances tumor suppression in an orthotopic HCC rat model. The tumor suppression is associated to the enhanced immune responses in terms of recruiting the important cell subpopulations such as CD8 + T-cells and NK cells into tumor microenvironment and abolishing immune suppressor such as Treg cells.

Childcare needs as a barrier to healthcare among women in a safety-net health system.

BACKGROUND: Childcare needs are an understudied social determinant of health. The effect of childcare needs on access to healthcare must be understood to inform health system interventions and policy reform. This study sought to characterize childcare needs, access to childcare, and prior experience with navigating childcare needs in healthcare settings among women in a safety-net population. METHODS: We conducted a cross-sectional study of patient-reported survey data collected in-person between April and October 2019. Surveys were administered in waiting rooms of ambulatory services in a large, urban safety-net health system in Dallas, Texas. Survey respondents were derived from a random convenience sample of women waiting for outpatient appointments. Participants were screened for having children under the age of 13 and/or childcare responsibilities for inclusion in the sample. Outcomes of interest included self-reported delayed or missed care, reasons for delayed or missed care, perceived difficulty in accessing childcare, prior methods for managing childcare during healthcare appointments, and prior experience with childcare centers. RESULTS: Among the 336 respondents (96.7% response rate), 121 (36.0%) reported delaying or missing a mean 3.7 appointments/year. Among women with delayed or missed care, 54.5% reported childcare barriers as the primary reason for deferral of care, greater than transportation (33%) or insurance (25%) barriers. Respondents rated childcare access as more difficult than healthcare access. Delayed or missed care due to childcare was more common among White (68.8%) and Black (55.0%) women compared to Hispanic women (34.3%). Common methods of navigating childcare needs during scheduled appointments included bringing children to appointments (69.1%) and re-scheduling or missing the scheduled appointment (43.0%). 40.6% of patients reported leaving an appointment before completion due to childcare needs. CONCLUSIONS: Childcare needs are a leading barrier to healthcare among women accessing care in safety-net settings. Unmet childcare needs result in deferral of care, which may impact health outcomes. Childcare access is perceived as more challenging than healthcare access itself. Health system and policy interventions are needed to address childcare as a social determinant of health.

Core-Shell Nanorods as Ultraviolet Light-Emitting Diodes.

Existing barriers to efficient deep ultraviolet (UV) light-emitting diodes (LEDs) may be reduced or overcome by moving away from conventional planar growth and toward three-dimensional nanostructuring. Nanorods have the potential for enhanced doping, reduced dislocation densities, improved light extraction efficiency, and quantum wells free from the quantum-confined Stark effect. Here, we demonstrate a hybrid top-down/bottom-up approach to creating highly uniform AlGaN core-shell nanorods on sapphire repeatable on wafer scales. Our GaN-free design avoids self-absorption of the quantum well emission while preserving electrical functionality. The effective junctions formed by doping of both the n-type cores and p-type caps were studied using nanoprobing experiments, where we find low turn-on voltages, strongly rectifying behaviors and significant electron-beam-induced currents. Time-resolved cathodoluminescence measurements find short carrier liftetimes consistent with reduced polarization fields. Our results show nanostructuring to be a promising route to deep-UV-emitting LEDs, achievable using commercially compatible methods.

Scanxiety in survivors of pancreatic cancer.

PURPOSE: To understand the scanxiety experience in pancreatic cancer (PC) survivors following curative surgical resection. DESIGN: A qualitative study with a hermeneutic phenomenological approach was used. METHODS: Eighteen PC survivors participated. Data from in-depth, semi-structured interviews were analyzed and themes emerged from systematic line-by-line coding of the interview transcripts. FINDINGS: Two key themes emerged: 'the recurring cycle of scanxiety' and 'hope for lifelong remission'. Participants experienced similar patterns of scanxiety that impacted everyday life. Hope was an essential stabilizing component of the cancer-scan experience, and enabled participants to conceptualize a cure, despite the high likelihood of recurrent, incurable disease. A conceptual framework was developed to provide further insight. IMPLICATIONS: Everyday life is significantly affected during times of PC surveillance scans. This study enhances our understanding of the cancer-scan experience and provides a framework to guide care.

Selective 1,2-Hydroarylation(Alkenylation) of gem-Difluoroalkenes to Access (-CF2 H) Motifs.

An emerging class of C-C coupling transformations that furnish drug-like building blocks involves catalytic hydrocarbonation of alkenes. However, despite notable advances in the field, hydrocarbon addition to gem-difluoroalkenes without additional electronic activation remains largely unsuccessful. This owes partly to poor reactivity and the propensity of difluoroalkenes to undergo defluorinative side reactions. Here, we report a nickel catalytic system that promotes efficient 1,2-selective hydroarylation and hydroalkenylation, suppressing defluorination and providing straightforward access to a diverse assortment of prized organofluorides bearing difluoromethyl-substituted carbon centers. In contrast to radical-based pathways and reactions triggered by hydrometallation via a nickel-hydride complex, our experimental and computational studies support a mechanism in which a catalytically active nickel-bromide species promotes selective carbonickelation with difluoroalkenes followed by alkoxide exchange and hydride transfer, effectively overcoming the difluoroalkene's intrinsic electronic bias.

Cyclopropenimine-Mediated CO2 Activation for the Synthesis of Polyurethanes and Small-Molecule Carbonates and Carbamates.

Carbon dioxide (CO2) is an abundant C1 feedstock with tremendous potential to produce versatile building blocks in synthetic applications. Given the adverse impact of CO2 on the atmosphere, it is of paramount importance to devise strategies for upcycling it into useful materials, such as polymers and fine chemicals. To activate such stable molecule, superbases offer viable modes of binding to CO2. In this study, a superbase cyclopropenimine derivative was found to exhibit exceptional proficiency in activating CO2 and mediating its polymerization at ambient temperature and pressure for the synthesis of polyurethanes. The versatility of this reaction can be extended to monofunctional amines and alcohols, yielding a variety of functional carbonates and carbamates.

Disparities in the Operative Experience Between Female and Male General Surgery Residents: A Multi-institutional Study From the US ROPE Consortium.

OBJECTIVE: To examine differences in resident operative experience between male and female general surgery residents. BACKGROUND: Despite increasing female representation in surgery, sex and gender disparities in residency experience continue to exist. The operative volume of male and female general surgery residents has not been compared on a multi-institutional level. METHODS: Demographic characteristics and case logs were obtained for categorical general surgery graduates between 2010 and 2020 from the US Resident OPerative Experience Consortium database. Univariable, multivariable, and linear regression analyses were performed to compare differences in operative experience between male and female residents. RESULTS: There were 1343 graduates from 20 Accreditation Council for Graduate Medical Education-accredited programs, and 476 (35%) were females. There were no differences in age, race/ethnicity, or proportion pursuing fellowship between groups. Female graduates were less likely to be high-volume residents (27% vs 36%, P < 0.01). On univariable analysis, female graduates performed fewer total cases than male graduates (1140 vs 1177, P < 0.01), largely due to a diminished surgeon junior experience (829 vs 863, P < 0.01). On adjusted multivariable analysis, female sex was negatively associated with being a high-volume resident (OR = 0.74, 95% CI: 0.56 to 0.98, P = 0.03). Over the 11-year study period, the annual total number of cases increased significantly for both groups, but female graduates (+16 cases/year) outpaced male graduates (+13 cases/year, P = 0.02). CONCLUSIONS: Female general surgery graduates performed significantly fewer cases than male graduates. Reassuringly, this gap in operative experience may be narrowing. Further interventions are warranted to promote equitable training opportunities that support and engage female residents.

Infection reporting in patients undergoing irreversible electroporation of locally advanced pancreatic cancer.

BACKGROUND: Intraoperative bile cultures (IOBCs) taken during pancreatic surgery are commonly performed and there has been limited evidence that a positive IOBC could aid in perioperative adverse event (AE) management. Therefore, this study aims to describe infection management in patients undergoing irreversible electroporation (IRE). METHODS: An Institutional Review Board (IRB)-approved prospective database was utilized from 8/2016 to 6/2022, with 127 pancreatic adenocarcinoma patients included. RESULTS: A total of 28 patients that underwent IRE also had a simultaneous positive IOBC and the remaining 99 patients that underwent IRE had negative IOBC. A total of 11(39%) of the patients with a positive IOBC had AE's, and 38 (38%) of the patients with negative IOBC had AE's. Both groups had similar rates of AEs leading to new hospitalization and prolonged hospitalizations. Overall, there was no correlation between a positive IOBC and a patient developing an AE. CONCLUSIONS: The findings of this study provide insights that improve the infectious management of patients undergoing IRE.

Imaging of Suspected Stroke in Children, From the AJR Special Series on Emergency Radiology.

Pediatric stroke encompasses different causes, clinical presentations, and associated conditions across ages. Although it is relatively uncommon, pediatric stroke presents with poor short- and long-term outcomes in many cases. Because of a wide range of overlapping presenting symptoms between pediatric stroke and other more common conditions, such as migraine and seizures, stroke diagnosis can be challenging or delayed in children. When combined with a comprehensive medical history and physical examination, neuroimaging plays a crucial role in diagnosing stroke and differentiating stroke mimics. This review highlights the current neuroimaging workup for diagnosing pediatric stroke in the emergency department, describes advantages and disadvantages of different imaging modalities, highlights disorders that predispose children to infarct or hemorrhage, and presents an overview of stroke mimics. Key differences in the initial approach to suspected stroke between children and adults are also discussed.

Biofuel blending reduces particle emissions from aircraft engines at cruise conditions.

Aviation-related aerosol emissions contribute to the formation of contrail cirrus clouds that can alter upper tropospheric radiation and water budgets, and therefore climate. The magnitude of air-traffic-related aerosol-cloud interactions and the ways in which these interactions might change in the future remain uncertain. Modelling studies of the present and future effects of aviation on climate require detailed information about the number of aerosol particles emitted per kilogram of fuel burned and the microphysical properties of those aerosols that are relevant for cloud formation. However, previous observational data at cruise altitudes are sparse for engines burning conventional fuels, and no data have previously been reported for biofuel use in-flight. Here we report observations from research aircraft that sampled the exhaust of engines onboard a NASA DC-8 aircraft as they burned conventional Jet A fuel and a 50:50 (by volume) blend of Jet A fuel and a biofuel derived from Camelina oil. We show that, compared to using conventional fuels, biofuel blending reduces particle number and mass emissions immediately behind the aircraft by 50 to 70 per cent. Our observations quantify the impact of biofuel blending on aerosol emissions at cruise conditions and provide key microphysical parameters, which will be useful to assess the potential of biofuel use in aviation as a viable strategy to mitigate climate change.