Establishing an optimized ATAC-seq protocol for the maize.

The advent of next-generation sequencing in crop improvement offers unprecedented insights into the chromatin landscape closely linked to gene activity governing key traits in plant development and adaptation. Particularly in maize, its dynamic chromatin structure is found to collaborate with massive transcriptional variations across tissues and developmental stages, implying intricate regulatory mechanisms, which highlights the importance of integrating chromatin information into breeding strategies for precise gene controls. The depiction of maize chromatin architecture using Assay for Transposase Accessible Chromatin with high-throughput sequencing (ATAC-seq) provides great opportunities to investigate cis-regulatory elements, which is crucial for crop improvement. In this context, we developed an easy-to-implement ATAC-seq protocol for maize with fewer nuclei and simple equipment. We demonstrate a streamlined ATAC-seq protocol with four key steps for maize in which nuclei purification can be achieved without cell sorting and using only a standard bench-top centrifuge. Our protocol, coupled with the bioinformatic analysis, including validation by read length periodicity, key metrics, and correlation with transcript abundance, provides a precise and efficient assessment of the maize chromatin landscape. Beyond its application to maize, our testing design holds the potential to be applied to other crops or other tissues, especially for those with limited size and amount, establishing a robust foundation for chromatin structure studies in diverse crop species.

Zaxinone Synthase overexpression modulates rice physiology and metabolism, enhancing nutrient uptake, growth and productivity.

The rice Zaxinone Synthase (ZAS) gene encodes a carotenoid cleavage dioxygenase (CCD) that forms the apocarotenoid growth regulator zaxinone in vitro. Here, we generated and characterized constitutive ZAS-overexpressing rice lines, to better understand ZAS role in determining zaxinone content and regulating growth and architecture. ZAS overexpression enhanced endogenous zaxinone level, promoted root growth and increased the number of productive tillers, leading to about 30% higher grain yield per plant. Hormone analysis revealed a decrease in strigolactone (SL) content, which we confirmed by rescuing the high-tillering phenotype through application of a SL analogue. Metabolomics analysis revealed that ZAS overexpressing plants accumulate higher amounts of monosaccharide sugars, in line with transcriptome analysis. Moreover, transgenic plants showed higher carbon (C) assimilation rate and elevated root phosphate, nitrate and sulphate level, enhancing the tolerance towards low phosphate (Pi). Our study confirms ZAS as an important determinant of rice growth and architecture and shows that ZAS regulates hormone homoeostasis and a combination of physiological processes to promote growth and grain yield, which makes this gene an excellent candidate for sustainable crop improvement.

Novel artesunate-metformin conjugate inhibits bladder cancer cell growth associated with Clusterin/SREBP1/FASN signaling pathway.

Bladder cancer remains the 10th most common cancer worldwide. In recent years, metformin has been found to have potential anti-bladder cancer activity while high concentration of IC50 at millimolar level is needed, which could not be reached by regular oral administration route. Thus, higher efficient agent is urgently demanded for clinically treating bladder cancer. Here, by conjugating artesunate to metformin, a novel artesunate-metformin dimer triazine derivative AM2 was designed and synthesized. The inhibitory effect of AM2 on bladder cancer cell line T24 and the mechanism underlying was determined. Anti-tumor activity of AM2 was assessed by MTT, cloning formation and wound healing assays. Decreasing effect of AM2 on lipogenesis was determined by oil red O staining. The protein expressions of Clusterin, SREBP1 and FASN in T24 cells were evaluated by Western blotting. The results show that AM2 significantly inhibited cell proliferation and migration at micromolar level, much higher than parental metformin. AM2 reduced lipogenesis and down-regulated the expressions of Clusterin, SREBP1 and FASN. These results suggest that AM2 inhibits the growth of bladder cancer cells T24 by inhibiting cellular lipogenesis associated with the Clusterin/SREBP1/FASN signaling pathway.

Exome sequencing and genome-wide association analyses unveils the genetic predisposition in hydroxychloroquine retinopathy.

OBJECTIVES: To unveil the candidate susceptibility genes in chloroquine/hydroxychloroquine (CQ/HCQ) retinopathy using whole exome sequencing (WES) and genome-wide association study (GWAS). METHODS: Patients with a diagnosis of CQ/HCQ retinopathy based on the comprehensive demographic and ocular examination were included. The peripheral blood was extracted for WES and GWAS analyses. The Chinese Han Southern database from 1000 genomes was used as control group to compare the affected percentage. Multivariate logistic regression analysis adjusted for age, HCQ dose, duration and renal disease were used to analyze the correlation between genetic variants and visual outcome. A poor vision outcome was defined as visual acuity <6/12. An abnormal anatomical outcome was defined as disruption of ellipsoid zone in the fovea. RESULTS: Twenty-nine patients with an average age of 60.9 ± 13.4 years, treatment duration of 12.1 ± 6.2 years, daily dose of 8.5 ± 4.1 mg/kg, and the cumulative dose of 1637.5 ± 772.5 g, were genotyped. Several candidate genes associated with CQ/HCQ retinopathy were found, including RP1L1, RPGR and RPE65, with a difference of affected percentage over 50% in mutation between the case and control groups. New foci in CCDC66: rs56616026 (OR = 63.43, p = 1.63 × 10-8) and rs56616023 (OR = 104.7, p = 5.02 × 10-10) were identified significantly associated with HCQ retinopathy. Multivariate analysis revealed increased genetic variants were significantly associated with poor functional (OR = 1.600, p = 0.004) and structural outcome (OR = 1.318, p = 0.043). CONCLUSIONS: Several candidate susceptibility genes including RP1L1, RPGR, RPE65 and CCDC66 were identified to be associated with CQ/HCQ retinopathy. In addition to disease susceptibility, patients with increased genetic variants are more vulnerable to poor visual outcomes.

ARF4-mediated retrograde trafficking as a driver of chemoresistance in GBM.

BACKGROUND: Cellular functions hinge on the meticulous orchestration of protein transport, both spatially and temporally. Central to this process is retrograde trafficking, responsible for targeting proteins to the nucleus. Despite its link to many diseases, the implications of retrograde trafficking in glioblastoma (GBM) are still unclear. METHODS: To identify genetic drivers of TMZ resistance, we conducted comprehensive CRISPR-knockout screening, revealing ADP-ribosylation factor 4 (ARF4), a regulator of retrograde trafficking, as a major contributor. RESULTS: Suppressing ARF4 significantly enhanced TMZ sensitivity in GBM patient-derived xenograft (PDX) models, leading to improved survival rates (p<0.01) in both primary and recurrent lines. We also observed that TMZ exposure stimulates ARF4-mediated retrograde trafficking. Proteomics analysis of GBM cells with varying levels of ARF4 unveiled the influence of this pathway on EGFR signaling, with increased nuclear trafficking of EGFR observed in cells with ARF4 overexpression and TMZ treatment. Additionally, spatially-resolved RNA-sequencing of GBM patient tissues revealed substantial correlations between ARF4 and crucial nuclear EGFR (nEGFR) downstream targets, such as MYC, STAT1, and DNA-PK. Decreased activity of DNA-PK, a DNA repair protein downstream of nEGFR signaling that contributes to TMZ resistance, was observed in cells with suppressed ARF4 levels. Notably, treatment with DNA-PK inhibitor, KU57788, in mice with a recurrent PDX line resulted in prolonged survival (p<0.01), highlighting the promising therapeutic implications of targeting proteins reliant on ARF4-mediated retrograde trafficking. CONCLUSION: Our findings demonstrate that ARF4-mediated retrograde trafficking contributes to the development of TMZ resistance, cementing this pathway as a viable strategy to overcome chemoresistance in GBM.

Pseudopterygia in Fuchs Superficial Marginal Keratitis: Clinical Course and Surgical Outcome.

PURPOSE: Surgery for pseudopterygia in Fuchs superficial marginal keratitis (FSMK) bears the risk of corneal perforation, as described in a few case reports. The aim of this case series was to understand the clinical course and surgical outcomes of pseudopterygia in FSMK. METHODS: A retrospective case series included patients meeting FSMK criteria with pseudopterygia in at least 1 eye. The severity grading of pseudopterygia and peripheral infiltration events at follow-up were analyzed. Pseudopterygia involving corneal central 3 mm diameter (grade III) received surgery. Peripheral corneal infiltrate events within 1 week after surgery were recorded. RESULTS: Thirty-three eyes of 19 patients (8 men, 11 women; age 40-85 years; mean, 65 years) were included, with an average 48.1-month follow-up (range 0-188.8 months). At presentation, 7 eyes (21%) had grade III pseudopterygia. One patient showed corneal perforation 3 days after "pterygium" surgery elsewhere. The contralateral eye met the diagnosis of FSMK. During follow-up, 16 eyes (49%) exhibited peripheral corneal infiltrates, and 7 eyes (21%) showed progression of pseudopterygia to higher grades before or without any surgery. Ten eyes with grade III pseudopterygia underwent surgery. The best-corrected visual acuity in Logarithm of the Minimum Angle of Resolution improved from 0.34 ± 0.18 (range 0.05-0.52) to 0.13 ± 0.11 (range 0.05-0.4) (P = 0.0023). Six eyes (60%) developed peripheral corneal infiltrates within 1 week after surgery, which responded well to topical corticosteroids. CONCLUSIONS: Pseudopterygia in FSMK may progress to threaten visual acuity. Surgical excision can be safe and can effectively improve vision on the condition that the patients are closely followed in the early postoperative period to notice the corneal infiltrates.

Risk factors for the development of oral precancerous lesions in a cohort of 293 oral lichen planus patients with or without chronic periodontitis in southern Taiwan.

Background/purpose: Oral lichen planus (OLP) may contribute to the risk of chronic periodontitis, and no reports have shown whether OLP patients with periodontitis have a greater risk of oral precancerous lesions, Candida infection or other clinicopathological diseases. This study aimed to assess the risk factors for the development of oral precancerous lesions in a cohort of 293 OLP patients with or without chronic periodontitis in southern Taiwan. Materials and methods: The current study recruited 293 OLP patients without preexisting periodontitis at a tertiary institution from 1995 to 2018. The patients were divided into two groups based on the presence or absence of periodontitis. The study compared various clinical and pathological characteristics between the two groups, and also estimated the odds ratio (OR) and the 10-year cumulative risk of chronic periodontitis in OLP patients using logistic regression models and Kaplan‒Meier analysis methods, respectively. Results: After adjusting for age and gender, the significant contributors to oral precancerous lesions in OLP patients (P < 0.05) were periodontal disease (OR = 2.24) and the male gender (OR = 7.52). Betel nut consumption (OR = 2.61), smoking (OR = 2.46), and candidiasis infection (OR = 3.02) also showed significant associations. Older OLP patients had a lower lesion risk, while a longer OLP duration heightened the periodontal disease likelihood. Conclusion: The present study demonstrated that coexisting periodontal disease increases the likelihood of developing precancerous lesions in patients with OLP. Periodontal management with oral hygiene care and quitting betel nut consumption and smoking can reduce the risk.

Guard Cell-Inspired Ion Channels: Harnessing the Photomechanical Effect via Supramolecular Assembly of Cross-Linked Azobenzene/Polymers.

Stimuli-responsive ion nanochannels have attracted considerable attention in various fields because of their remote controllability of ionic transportation. For photoresponsive ion nanochannels, however, achieving precise regulation of ion conductivity is still challenging, primarily due to the difficulty of programmable structural changes in confined environments. Moreover, the relationship between noncontact photo-stimulation in nanoscale and light-induced ion conductivity has not been well understood. In this work, a versatile design for fabricating guard cell-inspired photoswitchable ion channels is presented by infiltrating azobenzene-cross-linked polymer (AAZO-PDAC) into nanoporous anodic aluminum oxide (AAO) membranes. The azobenzene-cross-linked polymer is formed by azobenzene chromophore (AAZO)-cross-linked poly(diallyldimethylammonium chloride) (PDAC) with electrostatic interactions. Under UV irradiation, the trans-AAZO isomerizes to the cis-AAZO, causing the volume compression of the polymer network, whereas, in darkness, the cis-AAZO reverts to the trans-AAZO, leading to the recovery of the structure. Consequently, the resultant nanopore sizes can be manipulated by the photomechanical effect of the AAZO-PDAC polymers. By adding ionic liquids, the ion conductivity of the light-driven ion nanochannels can be controlled with good repeatability and fast responses (within seconds) in multiple cycles. The ion channels have promising potential in the applications of biomimetic materials, sensors, and biomedical sciences.

Novel Manifestation of Corneal Dystrophy After Keratorefractive Surgery.

PURPOSE: This study aimed to report cases of bilateral corneal Bowman layer deposits in 4 patients with a history of keratorefractive surgery. To our knowledge, this condition has not previously been reported and should be distinguished from granular corneal dystrophy type 2 and other corneal dystrophies. METHODS: We reviewed all available medical records that were collected between January 2010 and December 2021 at a tertiary referral center and performed whole-exome sequencing to provide diagnostic information. RESULTS: Four patients exhibited similar bilateral corneal deposits that were observed more than 10 years after keratorefractive surgery. The patients' ages ranged from 36 to 53 years; 3 of the 4 patients were female. Three patients received laser in situ keratomileusis surgery, and 1 received radial keratotomy. All 4 patients denied having a family history of ocular diseases and reported an uneventful postoperative course. On examination, the best-corrected visual acuity ranged from 6/10 to 6/6 in all 4 patients. Slit-lamp examination revealed bilateral superficial corneal deposits involving the central cornea, and anterior segment optical coherence tomography revealed hyperreflective deposits located in the Bowman layer. Such unique manifestations suggested corneal dystrophy; thus, whole-exome sequencing was performed on all 4 patients. Only 1 patient exhibited a missense mutation in TGFBI . We further analyzed common de novo mutations to explore possible candidate genes associated with this presentation. CONCLUSIONS: We report a rare entity of presumed corneal dystrophy with deposits located in the Bowman layer in 4 patients who had received keratorefractive surgery. Clarifying the underlying pathophysiology and genetic predisposition of this disease may aid in diagnosing and preventing potential complications after keratorefractive surgery.

Estimating genome-wide DNA methylation heterogeneity with methylation patterns.

BACKGROUND: In a heterogeneous population of cells, individual cells can behave differently and respond variably to the environment. This cellular diversity can be assessed by measuring DNA methylation patterns. The loci with variable methylation patterns are informative of cellular heterogeneity and may serve as biomarkers of diseases and developmental progression. Cell-to-cell methylation heterogeneity can be evaluated through single-cell methylomes or computational techniques for pooled cells. However, the feasibility and performance of these approaches to precisely estimate methylation heterogeneity require further assessment. RESULTS: Here, we proposed model-based methods adopted from a mathematical framework originally from biodiversity, to estimate genome-wide DNA methylation heterogeneity. We evaluated the performance of our models and the existing methods with feature comparison, and tested on both synthetic datasets and real data. Overall, our methods have demonstrated advantages over others because of their better correlation with the actual heterogeneity. We also demonstrated that methylation heterogeneity offers an additional layer of biological information distinct from the conventional methylation level. In the case studies, we showed that distinct profiles of methylation heterogeneity in CG and non-CG methylation can predict the regulatory roles between genomic elements in Arabidopsis. This opens up a new direction for plant epigenomics. Finally, we demonstrated that our score might be able to identify loci in human cancer samples as putative biomarkers for early cancer detection. CONCLUSIONS: We adopted the mathematical framework from biodiversity into three model-based methods for analyzing genome-wide DNA methylation heterogeneity to monitor cellular heterogeneity. Our methods, namely MeH, have been implemented, evaluated with existing methods, and are open to the research community.

Portable multichannel detection instrument based on time-resolved fluorescence immunochromatographic test strip for on-site detecting pesticide residues in vegetables.

In this work, a portable multichannel detection instrument based on time-resolved fluorescence immunochromatographic test strip (TRFIS) was proposed for on-site detecting pesticide residues in vegetables. Its hardware consisted of a silicon photodiode and excitation light source array, a mainboard of the lower machine with STMicroelectronics 32 (STM32) and a linear stepping motor. While detecting, cardboard with 6-channel TRFIS was pulled into the cassette by the stepping motor. The peak area of the test (T) line and control (C) line of each TRFIS was sampled and calculated by software, then the concentration of the detected pesticide was obtained according to the ratio of the T to C value. This instrument could sample 6-channel TRFIS within 30 s simultaneously, and it exhibited excellent accuracy with a 2.5% average coefficient of variation for each channel (n = 12). In addition, the TRFIS was constructed by using europium oxide time-resolved fluorescent microspheres to label the monoclonal antibody against acetamiprid and form a fluorescent probe, which was fixed on the binding pad. The TRFIS was used for the detection of acetamiprid in celery cabbage, cauliflower and baby cabbage. This instrument was used to complete the qualitative and quantitative analysis of the TRFIS, so as to enhance the practical application of the detection method. This TRFIS possessed excellent linearity ranging from 0.25 mg kg-1 to 1.75 mg kg-1 for the detection of acetamiprid, and the limit of detection were 0.056-0.074 mg kg-1 in the different vegetable matrix. The platform combines the accuracy and portability of traditional test strips with the highly sensitive and efficient fluorescence intensity recognition function of detection equipment, which shows a great application prospect of multi-channel rapid detection of small molecule pollutants in the field.

Compact single-panel LCD projector with high uniformity.

In this study, we introduce a single-panel LCD projector that employs a direct-lit LED array as its illumination system. Each LED in the array is coupled to a Fresnel lens to ensure light collimation. To create a uniform light distribution on the LCD panel, the LED array is arranged in a hexagonal pattern. To eliminate the hotspot effects caused by individual LED units, the optical distance between each unit and the LCD panel is extended to allow sufficient light mixing. Köhler illumination is adopted to generate adequate and homogeneous illumination on the screen. With these design enhancements, we managed to shrink the system by 29% of the traditional designs and increase uniformity to 90.1%.

New Series of Zaxinone Mimics (MiZax) for Fundamental and Applied Research.

The apocarotenoid zaxinone is a recently discovered regulatory metabolite required for proper rice growth and development. In addition, zaxinone and its two mimics (MiZax3 and MiZax5) were shown to have a remarkable growth-promoting activity on crops and a capability to reduce infestation by the root parasitic plant Striga through decreasing strigolactone (SL) production, suggesting their potential for application in agriculture and horticulture. In the present study, we developed a new series of MiZax via structural modification of the two potent zaxinone mimics (MiZax3 and MiZax5) and evaluated their effect on plant growth and Striga infestation. In general, the structural modifications to MiZax3 and MiZax5 did not additionally improve their overall performance but caused an increase in certain activities. In conclusion, MiZax5 and especially MiZax3 remain the likely most efficient zaxinone mimics for controlling Striga infestation.

There's more to it: uncovering genomewide DNA methylation heterogeneity.

Tweetable abstract Monitoring changes in methylation heterogeneity can be powerful in detecting disease progression early. This editorial highlights the importance of profiling methylation heterogeneity and identifies existing measures and research gaps.

Biomimetic Mineralization for Smart Biostimulant Delivery and Crop Micronutrients Fortification.

Sustainable and precise fortification practices are necessary to ensure food security for the increasing human population. Precision agriculture aims to minimize the use of fertilizers and pesticides by developing smart materials for real-life agricultural practices. Here, we show that biomimetic mineralization can be efficiently employed to encapsulate and controllably release plant biostimulants (MiZax-3) to improve the quality and yield of capsicum (Capsicum annum) crops in field experiments. ZIF-8 encapsulation of MiZax-3 (MiZIFs) could significantly enhance its stability up to around 679 times (6p value = 0.0072) at field conditions. Our results demonstrate that the coordinating Zn ions and the MiZax-3 play a vital role in improving Zn content in the produced fruits by 2-fold, which is the first report of this nature on Zn content in fruits. We envision this platform as a starting point to investigate other biocompatible coordination-based platforms for micronutrient delivery in precision agriculture.

Ribonucleotide reductase regulatory subunit M2 drives glioblastoma TMZ resistance through modulation of dNTP production.

During therapy, adaptations driven by cellular plasticity are partly responsible for driving the inevitable recurrence of glioblastoma (GBM). To investigate plasticity-induced adaptation during standard-of-care chemotherapy temozolomide (TMZ), we performed in vivo single-cell RNA sequencing in patient-derived xenograft (PDX) tumors of GBM before, during, and after therapy. Comparing single-cell transcriptomic patterns identified distinct cellular populations present during TMZ therapy. Of interest was the increased expression of ribonucleotide reductase regulatory subunit M2 (RRM2), which we found to regulate dGTP and dCTP production vital for DNA damage response during TMZ therapy. Furthermore, multidimensional modeling of spatially resolved transcriptomic and metabolomic analysis in patients' tissues revealed strong correlations between RRM2 and dGTP. This supports our data that RRM2 regulates the demand for specific dNTPs during therapy. In addition, treatment with the RRM2 inhibitor 3-AP (Triapine) enhances the efficacy of TMZ therapy in PDX models. We present a previously unidentified understanding of chemoresistance through critical RRM2-mediated nucleotide production.

Monitoring ambient air pollution and pulmonary function in asthmatic children by mobile applications in COVID-19 pandemic.

BACKGROUND: Several public health measures were implemented during the COVID-19 pandemic. However, little is known about the real-time assessment of environmental exposure on the pulmonary function of asthmatic children. Therefore, we developed a mobile phone application for capturing real-time day-to-day dynamic changes in ambient air pollution during the pandemic. We aim to explore the change in ambient air pollutants between pre-lockdown, lockdowns, and lockdowns and analyze the association between pollutants and PEF mediated by mite sensitization and seasonal change. METHOD: A prospective cohort study was conducted among 511 asthmatic children from January 2016 to February 2022. Smartphone-app used to record daily ambient air pollution, particulate matter (PM2.5, PM10) Ozon (O3), nitrogen dioxide (NO2), Carbon Monoxide (CO), sulfur dioxide (SO2), average temperature, and relative humidity, which measured and connected from 77 nearby air monitoring stations by linking to Global Positioning System (GPS)-based software. The outcome of pollutants' effect on peak expiratory flow meter (PEF) and asthma is measured by a smart peak flow meter from each patient or caregiver's phone for real-time assessment. RESULTS: The lockdown (May 19th, 2021, to July 27th, 2021) was associated with decreased levels of all ambient air pollutants aside from SO2 after adjusting for 2021. NO2 and SO2 were constantly associated with decreased levels of PEF across lag 0 (same day when the PEF was measured), lag 1 (one day before PEF was measured), and lag 2 (two days prior when the PEF was measured. Concentrations of CO were associated with PEF only in children who were sensitized to mites in lag 0, lag 1, and lag 2 in the stratification analysis for a single air pollutant model. Based on the season, spring has a higher association with the decrease of PEF in all pollutant exposure than other seasons. CONCLUSION: Using our developed smartphone apps, we identified that NO2, CO, and PM10 were higher at the pre-and post-COVID-19 lockdowns than during the lockdown. Our smartphone apps may help collect personal air pollution data and lung function, especially for asthmatic patients, and may guide protection against asthma attacks. It provides a new model for individualized care in the COVID era and beyond.

Differential characteristics among asymptomatic and symptomatic meibomian gland dysfunction and those with dry eye.

PURPOSE: To identify the characteristics of asymptomatic meibomian gland dysfunction (MGD), symptomatic MGD, and MGD coexisting with dry eye disease (DED). METHODS: This cross sectional study enrolled a total of 153 eyes of 87 MGD patients. Participants filled in ocular surface disease index (OSDI) questionnaires. Age, gender, Schirmer's test, meibomian gland (MG) related parameters, lipid layer thickness (LLT) and blinking were compared among patients with asymptomatic MGD, symptomatic MGD, and MGD with DED. Multivariate regression was used to analyze the significant factor of DED in MGD. Spearman's rank correlation analysis was used to evaluate the association between the significant factors and MG function. RESULTS: There was no difference in age, Schirmer's test, lid changes, MG secretion, and MG morphology among three groups. The OSDI of asymptomatic MGD, symptomatic MGD and MGD coexisting with DED were 8.5 ± 2.9, 28.5 ± 12.8 and 27.9 ± 10.5, respectively. Patients with MGD coexisting with DED exhibited more frequent eye blinking than that of patients with asymptomatic MGD (8.1 ± 4.1 vs. 6.1 ± 3.5 blinks/20 sec, P = 0.022), and reduced LLT than that of patients with asymptomatic MGD (68.6 ± 17.2 vs. 77.6 ± 14.5 nm, P = 0.010) and symptomatic MGD (78.0 ± 17.1 nm, P = 0.015). Multivariate analysis identified LLT (per nm, OR = 0.96, 95% CI = 0.93-0.99, P = 0.002) as a significant factor associated with DED development in MGD. The number of expressible MG was positively correlated with LLT (Spearman's correlation coefficient = 0.299, P = 0.016) but negatively correlated with the number of blinking (Spearman's correlation coefficient = -0.298, P = 0.016) in MGD patients with DED, and these findings were not identified in those without DED. CONCLUSIONS: Asymptomatic MGD, symptomatic MGD, and MGD coexisting with DED share similar characteristics, including meibum secretion and morphology, but MGD patients coexisting with DED exhibited significantly reduced LLT.

Patients with abdominal aortic aneurysms have reduced levels of microRNA 122-5p in circulating exosomes.

OBJECTIVE: There are currently no specific biomarkers to identify patients with abdominal aortic aneurysms (AAAs). Circulating exosomes contain microRNAs (miRNA) that are potential biomarkers for the presence of disease. This study aimed to characterize the exosomal miRNA expression profile of patients with AAAs in order to identify novel biomarkers of disease. METHODS: Patients undergoing duplex ultrasound (US) or computed tomography (CT) for screening or surveillance of an AAA were screened to participate in the study. Cases with AAA were defined as having a max aortic diameter >3 cm. Circulating plasma exosomes were isolated using Cushioned-Density Gradient Ultracentrifugation and total RNA was extracted. Next Generation Sequencing was performed on the Illumina HiSeq4000 SE50. Differential miRNA expression analysis was performed using DESeq2 software with a Benjamini-Hochberg correction. MicroRNA expression profiles were validated by Quantitative Real-Time PCR. RESULTS: A total of 109 patients were screened to participate in the study. Eleven patients with AAA and 15 non-aneurysmal controls met study criteria and were enrolled. Ultrasound measured aortic diameter was significantly larger in the AAA group (mean maximum diameter 4.3 vs 2.0 cm, P = 6.45x10-6). More AAA patients had coronary artery disease (5/11 vs 1/15, P = 0.05) as compared to controls, but the groups did not differ significantly in the rates of peripheral arterial disease and chronic obstructive pulmonary disease. A total of 40 miRNAs were differentially expressed (P<0.05). Of these, 18 miRNAs were downregulated and 22 were upregulated in the AAA group compared to controls. After false discovery rate (FDR) adjustment, only miR-122-5p was expressed at significantly different levels in the AAA group compared to controls (fold change = 5.03 controls vs AAA; raw P = 1.8x10-5; FDR P = 0.02). CONCLUSION: Plasma exosomes from AAA patients have significantly reduced levels of miRNA-122-5p compared to controls. This is a novel exosome-associated miRNA that warrants further investigation to determine its use as a diagnostic biomarker and potential implications in AAA pathogenesis.