Functional Changes Research Articles

Improved Pyroelectric Nanogenerator Performance of P(VDF-TrFE)/rGO Thin Film by Optimized rGO Reduction.

The pyroelectric nanogenerator (PyNG) has gained increasing attention due to its capability of converting ambient or waste thermal energy into electrical energy. In recent years, nanocomposite films of poly(vinylidene fluoride-co-trifluoro ethylene) (P(VDF-TrFE)) and nanofillers such as reduced graphene oxide (rGO) have been employed due to their high flexibility, good dielectric properties, and high charge mobility for the application of wearable devices. This work investigated the effect of rGO reduction on pyroelectric nanogenerator performance. To prepare rGO, GO was reduced with different reducing agents at various conditions. The resulting rGO samples were characterized by XPS, FT-IR, XRD, and electrical conductivity measurements to obtain quantitative and qualitative information on the change in surface functionalities. Molecularly thin nanocomposite films of P(VDF-TrFE)/rGO were deposited on an ITO-glass substrate by the Langmuir-Schaefer (LS) technique. A PyNG sandwich-like structure was fabricated by arranging the thin films facing each other, and it was subjected to the pyroelectric current test. For various PyNGs of the thin films containing rGO prepared by different methods, the average pyroelectric peak-to-peak current (APC) and the pyroelectric coefficient (p) values were measured. It was found that a more reduced rGO resulted in higher electrical conductivity, and the thin films containing rGO of higher conductivity yielded higher APC and p values and, thus, better energy-harvesting performance. However, the thin films having rGO of too high conductivity produced slightly reduced performance. The Maxwell-Wagner effect in the two-phase system successfully explained these optimization results. In addition, the APC and p values for the thin film with the best performance increased with increasing temperature range. The current PyNG's performance with an energy density of 3.85 mW/cm2 and a p value of 334 μC/(m2∙K) for ΔT = 20 °C was found to be superior to that reported in other studies in the literature. Since the present PyNG showed excellent performance, it is expected to be promising for the application to microelectronics including wearable devices.

Co-mutation of TP53 and TTN is Correlated with the Efficacy of Immunotherapy in Lung Squamous Cell Carcinoma.

Immunotherapy has been a promising treatment in advanced lung cancer. However, only a few patients could benefit from it. Herein, we aimed to explore mutationrelated predictive biomarkers in lung squamous cell carcinoma (LUSC), which could help develop clinical immunotherapy strategies and screen beneficial populations. Co-occurrence and mutually exclusive analysis was conducted on the TCGA-LUSC cohort. Correlations between the gene mutation status and tumor mutation burden (TMB) levels, and neo-antigen levels were analyzed by Wilcoxon test. Kaplan-Meier method was employed to analyze the progression-free survival (PFS) of lung cancer patients with immunotherapy. Gene set enrichment analysis (GSEA) was used to investigate the functional changes affected by TP53mut/TTNmut. The immune cell infiltration landscape in co-mutation subgroups was analyzed using CIBERSORT. 1) TP53, TTN, CSMD3, MUC16, RYR2, LRP1B, USH2A, SYNE1, ZFHX4, FAM135B, KMT2D, and NAV3 were frequently mutated in LUSC patients. 2) TMB levels in highly mutated groups were higher than that in wild type groups. 3) There were higher neoantigen levels in mutation group compared to the wild-type group, and LUSC patients in mutation group had longer PFS. 4) TP53mut/TTNmut co-mutation group exhibited higher TMB levels and better response to immunotherapy. 5) A host of immune-related signaling pathways was inhibited in TP53mut/TTNmut subgroup. 6) There were more T follicular helper cells and NK cells were in TP53mut/TTNmut subgroup than in the WT subgroup. The LUSC patients with TP53 and TTN co-mutation had higher TMB levels and better response to immunotherapy. The TP53 and TTN co-mutation is a promising novel biomarker to assist LUSC immunotherapy evaluation.

By-product distribution and cytotoxicity assessment of ZnO-assisted photocatalytic degradation of reactive blue 250 dye

This research examined the effectiveness and feasibility of utilizing ultraviolet (UV) assisted photo-catalysis to treat wastewater effluents from textile production containing reactive blue 250 (RB 250) dye. Molecular oxygen and active species like O2•−, HO2•, H2O2 and •OH play crucial roles in the degradation process. Additionally, the degradation of dyes is influenced by several factors, including dye concentration, duration of UV irradiation, pH levels, concentration of H2O2, and the catalyst. The concentration of H2O2 and catalyst dose for the decolorization was studied at 0.6 mL and 0.5 g respectively. The discoloration was higher at low dye concentration, high H2O2 concentration, acidic conditions and high catalyst concentration. The maximum degradation (97 %) of RB 250 dye was obtained in the presence of zinc oxide nanoparticles within 90 min. The extent of decolorization of the dye was determined by UV–Vis spectroscopy. Fourier transform infrared spectroscopy (FTIR) was employed to analyze the changes in functionalities after degradation. The disappearance of characteristic peaks associated with specific groups within the dye molecule confirmed the extensive degradation of RB 250 dye. LCMS analysis was conducted to examine the intermediates and a mechanistic degradation pathway was subsequently proposed. The cytotoxicity of the irradiated dye samples was evaluated through a hemolytic test both pre and post-treatment. The findings suggest that the UV/H2O2/ZnO treatment represents a promising approach for effectively degrading RB 250 dye.

Contrasting conformational behaviors of molecules XXXI and XXXII in the seventh blind test of crystal structure prediction.

Accurate modeling of conformational energies is key to the crystal structure prediction of conformational polymorphs. Focusing on molecules XXXI and XXXII from the seventh blind test of crystal structure prediction, this study employs various electronic structure methods up to the level of domain-local pair natural orbital coupled cluster singles and doubles with perturbative triples [DLPNO-CCSD(T1)] to benchmark the conformational energies and to assess their impact on the crystal energy landscapes. Molecule XXXI proves to be a relatively straightforward case, with the conformational energies from generalized gradient approximation (GGA) functional B86bPBE-XDM changing only modestly when using more advanced density functionals such as PBE0-D4, ωB97M-V, and revDSD-PBEP86-D4, dispersion-corrected second-order Møller-Plesset perturbation theory (SCS-MP2D), or DLPNO-CCSD(T1). In contrast, the conformational energies of molecule XXXII prove difficult to determine reliably, and variations in the computed conformational energies appreciably impact the crystal energy landscape. Even high-level methods such as revDSD-PBEP86-D4 and SCS-MP2D exhibit significant disagreements with the DLPNO-CCSD(T1) benchmarks for molecule XXXII, highlighting the difficulty of predicting conformational energies for complex, drug-like molecules. The best-converged predicted crystal energy landscape obtained here for molecule XXXII disagrees significantly with what has been inferred about the solid-form landscape experimentally. The identified limitations of the calculations are probably insufficient to account for the discrepancies between theory and experiment on molecule XXXII, and further investigation of the experimental solid-form landscape would be valuable. Finally, assessment of several semi-empirical methods finds r2SCAN-3c to be the most promising, with conformational energy accuracy intermediate between the GGA and hybrid functionals and a low computational cost.

Final COMPASS Results on the Transverse-Spin-Dependent Azimuthal Asymmetries in the Pion-Induced Drell-Yan Process.

The COMPASS Collaboration performed measurements of the Drell-Yan process in 2015 and 2018 using a 190 GeV/c π^{-} beam impinging on a transversely polarized ammonia target. Combining the data of both years, we present final results on the amplitudes of five azimuthal modulations, which correspond to transverse-spin-dependent azimuthal asymmetries (TSAs) in the dimuon production cross section. Three of them probe the nucleon leading-twist Sivers, transversity, and pretzelosity transverse-momentum dependent (TMD) parton distribution functions (PDFs). The other two are induced by subleading effects. These TSAs provide unique new inputs for the study of the nucleon TMD PDFs and their universality properties. In particular, the Sivers TSA observed in this measurement is consistent with the fundamental QCD prediction of a sign change of naive time-reversal-odd TMD PDFs when comparing the Drell-Yan process with deep inelastic scattering. Also, within the context of model predictions, the observed transversity TSA is consistent with the expectation of a sign change for the Boer-Mulders function.

CRISPRi-based screens in iAssembloids to elucidate neuron-glia interactions.

The sheer complexity of the brain has complicated our ability to understand the cellular and molecular mechanisms underlying its function in health and disease. Genome-wide association studies have uncovered genetic variants associated with specific neurological phenotypes and diseases. In addition, single-cell transcriptomics have provided molecular descriptions of specific brain cell types and the changes they undergo during disease. Although these approaches provide a giant leap forward towards understanding how genetic variation can lead to functional changes in the brain, they do not establish molecular mechanisms. To address this need, we developed a 3D co-culture system termed iAssembloids (induced multi-lineage assembloids) that enables the rapid generation of homogenous neuron-glia spheroids. We characterize these iAssembloids with immunohistochemistry and single-cell transcriptomics and combine them with large-scale CRISPRi-based screens. In our first application, we ask how glial and neuronal cells interact to control neuronal death and survival. Our CRISPRi-based screens identified that GSK3β inhibits the protective NRF2-mediated oxidative stress response in the presence of reactive oxygen species elicited by high neuronal activity, which was not previously found in 2D monoculture neuron screens. We also apply the platform to investigate the role of APOE-ε4, a risk variant for Alzheimer's Disease, in its effect on neuronal survival. We find that APOE-ε4-expressing astrocytes may promote more neuronal activity as compared to APOE-ε3-expressing astrocytes. This platform expands the toolbox for the unbiased identification of mechanisms of cell-cell interactions in brain health and disease.

The dynamic changes in physicochemical properties, functionalities, and gel properties of the starch-konjac gum mixture during the melting process: Based on three typical melting temperatures of DSC

The present study focuses on investigating the effect of typical melting temperatures (To, Tp, and Tc from DSC) on the dynamic changes of physicochemical properties, functionalities, and gel properties of starch-konjac gum mixture (PS/KGM). The typical melting treatments (HTo, HTp, and HTc) significantly enhanced the PS/KGM synergism, as indicated by the increased thermal stability, and the improved pasting and gel properties. The work suggested that the typical melting effectively stabilized the aqueous mixture system of PS/KGM, showing no phase separation in the water phase system, even after storage for 12 h. The PLM and SEM show that melting at HTo, HTp, and HTc causes partial melting with the loss of birefringence of starch granules, and the granules conglomerate into large clusters with rough surfaces, surrounded by smaller matrices. DSC demonstrated that typical melting significantly raised the To of composite to approximately 77 from 59.10 °C for native. RVA suggested that the melting significantly increased the FV of PS/KGM from 3363 to approximately 8000 mPa s, while the BD decreased from 5009 to approximately 400 mPa·s. Especially in which there is no BD recorded when melted by HTp and HT. The PS/KGM melted by HTo and HTp had more acidic, salty, and shear stability during the thermal process with improved gel texture and freeze-thaw stability than HTc. Partial melting of starch and chain rearrangement is critical for enhancing PS/KGM synergism. As RC% and DM% controlling at approximately 30–35% are the most effective for promoting PS/KGM interaction (HTp > HTo > HTc).

Cerebral Small Vessel Disease in Population-Based Research: What are We Looking at - and What not?

Cerebral small vessel disease (CSVD) is considered as one of the main causes of cognitive decline and dementia. However, despite extensive research, the pathogenesis of CSVD and the mechanisms through which CSVD leads to its clinical manifestations remain largely unclear. The challenging in vivo quantification of CSVD hampers progress in further unraveling the pathogenesis and pathophysiology of CSVD. Currently, markers of CSVD are mainly brain abnormalities attributed to CSVD, but these are limited in reflecting morphological and functional changes of the microvasculature. We describe aspects of CSVD that are reflected by currently used techniques and those that are still insufficiently captured.

Combination of fermentation and enzymolysis enhances bioactive components and function of de-oiled rice bran.

De-oiled rice bran (DORB), a substantial yet underutilized byproduct of rice processing, boasts a rich composition of active ingredients but suffers from limited application. Previous studies have indicated that enzymatic or fermentation treatments enhanced these active components. In this study, lactobacilli and complex enzymes were employed to co-treat DORB, involving the determination of the changes in active components and functionalities of DORB extract (DORBE) before and after this treatment. Following fermentation-enzymolysis, the total phenol and total flavonoid contents in DORBE were significantly increased by 43.59% and 55.10%, reaching 19.66 and 34.34 g kg-1, respectively. Antioxidant tests in vitro demonstrated that the co-treatment enhanced the scavenging activities of DPPH, hydroxyl and ABTS radicals. Porcine intestinal epithelial cell experiments revealed that, compared to DORBE, the fermentation and enzymolysis DORBE (FDORBE) exhibited significantly improved cell viability and catalase activity as well as scavenging capacity for reactive oxygen species and malondialdehyde after induction by H2O2. Furthermore, FDORBE restored the decreased mRNA expression levels of Nrf2, HO-1 and NQO1 in the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway stimulated by H2O2. Fermentation-enzymolysis co-treatment increases the contents of bioactive components of DORBE and enhances its antioxidant capacity, leading to a better protection against intestinal disorders induced by oxidative stress, suggesting that this co-treatment is a rational and effective strategy to increase the value of grains and promotes the use of DORB as a functional feed in animal production. © 2024 Society of Chemical Industry.

Reorganization of the Flagellum Scaffolding Induces a Sperm Standstill During Fertilization.

In this work, we demonstrate that the helical structure of polymerized actin in the flagellum undergoes a rearrangement at the time of sperm-egg fusion. This process is driven by intracellular calcium and promotes a decrease in the sperm midpiece diameter as well as the arrest in motility, which is observed after the fusion process is initiated.

Unveiling enhanced sound absorption in coconut wood through hemicellulose and lignin modification

Coconut wood (Cocos nucifera L.) is lightweight and has variable quality, making it a potential candidate for manufacturing sound absorption boards. However, its sound absorption coefficient needs enhancement to optimize its effectiveness in this application. This study aims to enhance its sound absorption properties using eco-friendly hydrogen peroxide and acetic acid treatments. This treatment modified the carbohydrate polymers (hemicellulose and cellulose) and lignin structures in the wood cell wall. The novelty of this approach lies in using these chemicals to improve acoustic performance significantly. Coconut wood samples were treated with a 1:1 acetic acid and hydrogen peroxide mixture for 20, 40, 60, and 80 min. Characterization techniques such as FTIR, XPS, and XRD, and 3D optical profilometry analyzed changes in chemical functionalities, crystallinity, and surface roughness. Sound absorption coefficients were measured using the impedance tube method. Results showed a significant improvement in sound absorption for all treated samples, especially at 60 min. The treatment also enhanced surface roughness, air permeability, porosity, and pore sizes, contributing to better sound absorption. This proposed treatment method addresses environmental consciousness and enhances the sustainable use and utilization of coconut wood.

Characteristics of graphene oxide-like materials prepared from different deashed-devolatilized coal chars and comparison with graphite-based graphene oxide, with or without the ultrasonication treatment

Deashed-devolatilized coal chars were prepared from anthracite, bituminous, subbituminous, and lignite coals, then oxidized to prepare graphene oxide (GO)-like materials that were extensively characterized and compared with a pristine graphite-based GO sample (CGO). Coal-based GO-like materials and CGO were then subjected to ultrasonication treatment for delamination, which also impacted their physicochemical properties. The surface oxygen contents of CGO and coal-based samples were ∼32 % and ∼26–35 %, respectively, that were reduced to ∼27 % and ∼21–24 %, respectively, after ultrasonication. The Fourier transform infrared and X-ray photoelectron spectroscopy spectra of all samples showed different profiles before and after the ultrasonication, suggesting a change in chemical functionalities. The Raman spectra of CGO and coal-based samples exhibited similar D and G bands with D/G intensity ratios (ID/IG) of 0.93 and 0.88–0.92, respectively. The ID/IG ratio of CGO and most of the coal-based samples increased after the ultrasonication due to creation of more defects. The main X-ray diffraction (XRD) peak for CGO and coal-based samples were observed at ∼11° and ∼22–24°, respectively. Ultrasonication of the samples resulted in a reduction of crystallite size and number of layers for all CGO and coal-based samples, confirming both splitting and delamination of carbon layers. Additionally, different coal-based samples exhibited almost overlapping XRD profiles after the ultrasonication.

Development of the self-efficacy scale in caregivers of Duchenne muscular dystrophy patients.

It is important to measure the self-efficacy knowledge of the caregiver of Duchenne muscular dystrophy (DMD) patients in order to overcome the problems that arise and carry out the care process in a healthy manner. This research was carried out to develop a self-efficacy scale in caregivers of individuals with DMD. The study was conducted with 99 volunteer DMD caregivers to evaluate the psychometric properties of the developed scale. Exploratory Factor Analysis (EFA) was performed with the SPSS 25 Package Program to determine the factors of the scale. Confirmatory Factor Analysis (CFA) analysis was performed with AMOS 23 to confirm the factors obtained by EFA. Cronbach's alpha coefficient was used for the internal consistency of the DMD-CSES. A valid and reliable scale was obtained to measure the self-efficacy of caregivers of DMD patients. Although some scales have been developed to evaluate the care burden of family members who care for patient-centered symptoms and functional changes in patients with DMD, there is no single scale that adequately describes the conditions and resources of caregivers on a global scale. The search for a definitive scale is expected to continue until a definitive treatment for the disease is found. Developing a valid and reliable scale to identify the self-efficacy, knowledge, skills and resources of caregivers with a common perspective of physicians and health management team centred on patients with DMD will be effective in practice.

Left atrial strain analysis in the realm of pediatric cardiology: Advantages and implications.

Left atrial (LA) strain analysis has emerged as a noninvasive technique for assessing LA function and early detection of myocardial deformation. Recently, its application has also shown promise in the pediatric population, spanning diverse cardiac conditions that demand accurate and sensitive diagnostic measures. This research article endeavors to explore the role of LA strain parameters and contribute to the growing body of knowledge in pediatric cardiology, paving the way for more effective and tailored approaches to patient care. A comprehensive literature review was conducted to gather evidence from studies using echocardiographic strain imaging techniques across pediatric populations. LA strain parameters exhibited greater sensitivity than conventional atrial function indicators, with early detection of diastolic dysfunction and LA remodeling in pediatric cardiomyopathy, children with multisystem inflammatory syndrome, rheumatic heart disease, as well as childhood renal insufficiency and obesity offering prognostic relevance as potential markers in these pediatric subpopulations. However, there remains a paucity of evidence concerning pediatric mitral valve pathology, justifying further exploration. LA strain analysis carries crucial clinical and prognostic implications in pediatric cardiac conditions, with reliable accuracy and sensitivity to early functional changes.

Assessing Users’ Demand for Library Space: Insights from an Architecture School

The purpose of this paper is to conduct a post-occupancy evaluation to assess users’ feedback on the use of the architecture school library at Thammasat University, Thailand. The proposed study also has a specific objective: to explore users’ demand for library space in terms of academic library attributes. A case study of the library in the Faculty of Architecture and Planning was conducted at Thammasat University. Multiple data collection methods were used, including document analysis, a questionnaire survey, a workshop, and focus group interviews, to gather information on users’ demand for the library space. The findings confirm the relevance of the variables in the conceptual model from previous studies, which encompass three key attributes regarding users’ demand for library space: physical, social, and digital spaces. Functional obsolescence and changing learning approaches are revealed as dominant influential factors affecting users’ demand for library space. The connection between post-occupancy evaluation (POE) and pre-design evaluation (PDE) in the redevelopment of a real estate project is considered as a shift from performance measurement to performance management, assisting in establishing agreed-upon performance goals for the operation. This study’s findings, derived from a single case study, do affect affect generalisability. However, the study provides insights into academic library design and renovation by emphasising the alignment of library spaces with user needs for improved service effectiveness and user satisfaction. The research introduces an integration of POE and PDE, proposing a methodological framework for future library space redevelopment that could contribute to the broader discussion on library design and user experience.

The influence of nanoparticle size, concentration, and functionalization on drilling fluid filtration properties

This research investigates the effect of the surface properties of silicon dioxide (SiO2) nanoparticles on the filtration properties of water-based drilling fluid. The nanoparticles were synthesized in-house using a one-step sol-gel method and functionalized into different charges. Different sizes, concentrations, and functionalization of water-based drilling fluid were subjected to standard API and HPHT filtration tests. Regression analysis and ANOVA were carried out to develop a model for future prediction and classify each independent variable's significance. The result shows that the positively charged nanoparticles had better filtration properties, as evidenced by the lower filtrate volume. Functionalization levels had minimal impact on filtration properties, and the effect of concentration was insignificant above 0.4 v/v%. In terms of nanoparticle size, 120 nm showed a more consistent result despite varying concentration and functionalization. In contrast, smaller nanoparticle sizes are more susceptible to changes in concentration and functionalization but could produce the least filtrate volume with the appropriate combination of concentration and functionalization. Filtrate analysis shows that about 25–28 % of the drilling fluid nanoparticles can infiltrate the porous media. Furthermore, this study challenges existing models on the improvement of the filtration properties by using nanoparticles. While previous hypothesis relied on physical bridging mechanism, new evidence from this research suggests that the enhancement is primarily based on the surface properties of the nanoparticles. Specifically, the nanoparticles envelop the barite through monolayer adsorption, reducing the angularity and increasing the reaction sites with water molecules. This inhibits the mobility of the water molecules across the filter cakes, providing a novel understanding of the mechanisms underlying nanoparticle-enhanced filtration properties of drilling fluids. In summary, the filtration properties of water-based drilling fluid with nanoparticles are significantly influenced by the surface properties of the nanoparticles, with positively charged nanoparticles demonstrating superior performance in stable conditions.

Structural and functional abnormalities in the medial prefrontal cortex were associated with pain and depressive symptoms in patients with adhesive capsulitis.

Chronic pain and depression have been shown to coexist in patients with adhesive capsulitis (AC). Recent studies identified the shared brain plasticity between pain and depression; however, how such neuroplasticity contributes to AC remains unclear. Here, we employed a combination of psychophysics, structural MRI, and functional MRI techniques to examine the brain's structural and functional changes in AC. Fifty-two patients with AC and 52 healthy controls (HCs) were included in our study. Voxelwise comparisons were performed to reveal the differences in grey matter volume (GMV) and regional homogeneity (ReHo) between AC and HCs. Furthermore, region of interest to whole brain functional connectivity (FC) was calculated and compared between the groups. Finally, Pearson correlation coefficients were computed to reveal the association between clinical data and brain alterations. Mediation analyses were performed to investigate the path association among brain alterations and clinical measures. Three main findings were observed: (1) patients with AC exhibited a higher depression subscale of hospital anxiety and depression scale (HADS-D) score correlating with the GMV within the right medial prefrontal cortices (mPFC) compared with HCs; (2) relative to HCs, patients with AC exhibited lower ReHo within the right mPFC, which largely overlapped with the structural abnormalities; (3) the impact of pain duration on HADS-D score was mediated by ventral part of medial prefrontal cortices (vmPFC) GMV in patients with AC. In summary, our current findings suggest that vmPFC alterations correlate with both the pain duration and the emotional comorbidities experienced by patients with AC. Our research provides an enhanced comprehension of the underlying mechanisms of AC, thereby facilitating the development of more effective treatment approaches for AC.

Abstract 5567: Breast cancer cell alteration of immune cell transcriptome through indirect communication

Abstract Crosstalk between tumor and non-tumor cells plays an important role in cancer progression and metastasis often leading to a modification of non-malignant cells into pro-oncogenic phenotypes. Understanding this process is important for diagnostic and therapeutic advances. We previously reported clinical validation results for a new way to detect early-stage breast cancer using a panel of RNA biomarkers from whole blood and a machine learning software-powered testing system. Recently, we showed that immune cells undergo transcriptomic and functional changes upon direct contact with breast cancer cells. Here, we report results from investigation of indirect communication between breast cancer and immune cells leading to cancer-driven immune cell transformation and activation of multiple oncogenic pathways. To characterize these modifications, we performed RNAseq and pathway analysis on a human monocytic cell line, THP1, exposed to media from triple negative breast cancer (TNBC) cells (MDA-MB-231) in culture. Our results demonstrate that 24 hours of THP1 cell exposure to soluble factors secreted by tumor cells leads to significant gene modulation, with over 1,100 differentially expressed genes (|Fold Change|>2; p<0.05). KEGG and Reactome enrichment analysis revealed overlap of multiple pathways between THP1 cells exposed to direct and indirect cancer cell contact conditions, such as cytokine-cytokine receptor interaction, JAK-STAT signaling pathways and others. TNF, NMP1, STING1 and TGM2 were identified as key upstream regulators potentially driving this transformation in both direct and indirect contact conditions. The S100 pathway, which we previously found to be activated by fluid shear stress in MDA-MB-231 cells was also activated in THP1 cells upon both direct and indirect contact. The observed gene expression changes in THP1 cells exposed to media from MDA-MB-231 suggests that indirect intercellular communication alone can transmit an oncogenic signal. These results support a role for secreted factors from breast cancer cells in transforming immune cells and modulating the gene expression markers detected by our blood test, expanding the potential for leveraging this type of tumor education response in advancing cancer detection and treatment. Citation Format: Jacob Kennard, Karen Norek, Kenneth Fuh, Robert D. Shepherd, Kristina D. Rinker, Olesya A. Kharenko. Breast cancer cell alteration of immune cell transcriptome through indirect communication [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5567.

Abstract 1258: A cholesterol metabolite can modulate neutrophil-derived extracellular vesicles to promote breast cancer cell epithelial to mesenchymal transition (EMT) and stemness

Abstract Breast cancer is the second leading cause of cancer-related death in women, with mortality most often due to metastatic recurrence. Elevated cholesterol is associated with poor prognosis, with several potential mechanisms proposed. Work in murine models found that many of the pro-metastatic actions of cholesterol required the enzymatic conversion of cholesterol to 27-hydroxycholesterol (27HC), which functions as a ligand for both the estrogen receptors (ERs) and liver X receptors (LXRs). Importantly, we have found that 27HC promotes metastasis, in part through its actions on neutrophils. When examining mechanisms, we have made the observation that 27HC resulted in increased secretion of small extracellular vesicles (sEVs) from neutrophils. These 27HC-neutrophil-sEVs independently promote metastatic colonization. Since we have found that breast cancer cell lines can take up neutrophil-derived sEVs, we hypothesized that 27HC results in altered cargo within sEVs which leads to functional changes within cancer cells, the ultimate consequence of which being their increased metastatic potential. Using a non-biased small RNA-seq approach we have found that sEVs from 27HC-treated neutrophils had an altered miRNA signature. Bioinformatic analysis revealed several downregulated miRNAs from the let-7 subgroup. Let-7 miRs are known to target several genes associated with the WNT/β-catenin pathway, a pathway strongly implicated in epithelial to mesenchymal transition (EMT) and cancer cell stemness. Strikingly, breast cancer cells treated with sEVs from neutrophils treated with 27HC lost their adherent properties and adopted a mesenchymal and stem-like phenotype. In order to elucidate the mechanism by which these sEVs promote EMT and stemness, we performed comprehensive transcriptomics through time. Weighted gene co-expression network analysis (WGCNA) confirmed these phenotypic shifts, and implicated the WNT/β-catenin pathway, providing support to our hypothesis that the loss of let-7 miRs is the upstream mediator. Collectively, our data suggests that 27HC increases metastasis in part through its effects on neutrophils, by shifting sEVs cargo towards a loss of protective microRNA, resulting in increased EMT and stemness, and thus the ability of cancer cells to migrate, invade and metastasize. Funding: National Cancer Institute (ERN: R01CA234025) Department of Defense (ERN: BCRP Era of Hope Award), and Beckman Institute for Advanced Science and Technology (NK) Citation Format: Natalia J. Krawczynska, Yu Wang, Anasuya Das Gupta, Jenny Drnevich, Julie Ostrander, Erik R. Nelson. A cholesterol metabolite can modulate neutrophil-derived extracellular vesicles to promote breast cancer cell epithelial to mesenchymal transition (EMT) and stemness [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1258.

DEVELOPMENT OF ULTRASTRUCTURAL CHANGES IN DIAPHRAGM MUSCLE FIBERS DURING PARTIAL TRACHEAL STENOSIS IN YOUNG SEXUALLY IMMATURE RATS

Introduction. The study of congenital pathology of the respiratory tract in children is of great importance for theoretical and clinical pediatric otolaryngology. Currently, in the scientific literature there are single works concerning the study of the pathogenesis and clinic of laryngomalacia. First of all, this concerns the effect of acute and chronic hypoxia on the muscles of the respiratory system, in particular, the diaphragm. The aim of thіs work is to reveal the effect of hypoxia on the development of pronounced structural and functional changes in the diaphragm muscles of sexually immature animals when modeling partial tracheal occlusion. Materials and methods. Surgical partial occlusion of the trachea was performed on in sexually immature Wistar rats; we applied electron microscopy, morphometric and statistical research methods.
 Results. The obtained data demonstrated that the muscle fibers of the diaphragm are characterized by significant structural, functional and metabolic resistance to the development of acute or chronic hypoxia due to limited lung ventilation in rats. The density of muscle fibers did not change in any of the used terms of the experiment (7 and 21 days). On the 7th day of hypoxic exposure, a change in the state of the matrix of mitochondria of muscle fibers was observed, which was accompanied by partial ultrastructural rearrangements of the organization of these organelles. At the same time, no significant changes were observed during histological studies. Electrongrams demonstrated the ultrastructural damages were mainly limited to focal reduction of myofibrils and an increase in the mitochondria's diameter and found as especially pronounced on day 21 (a state of chronic hypoxia) on the muscular component of the respiratory system in rats. These changes are accompanied by the development of dystrophic disorders in the diaphragm myofibrils. On day 21 changes in the transendothelial transport of substance molecules were also detected. This was based on establishing the fact of a significant reduction in the number of pinocytosis vesicles in the cytoplasm of endothelial cells of diaphragm hemocapillaries in animals with partial tracheal occlusion. Disruption of the structural organization of actomyosin complexes was revealed in muscle fibers due to pathological changes in the mitochondria of myofibrils. It should be noted the development of destruction or complete loss of an important ultrastructural component of muscle fibers, Z-lines. These changes were completely absent on the 7th day following the influence of partial tracheal occlusion and the development of acute hypoxia. Moreover, on day 21, partial lysis of a significant amount of myofilaments of muscle fibers was observed. In addition, the development of the process of fiber swelling was detected against the background of which the above-mentioned ultrastructural destruction of the muscular component in the diaphragm was observed. These changes indicate the need for earlier treatment of laryngomalacia in children. The delay in surgical intervention leads to the development of severe or irreversible structural changes not only in the respiratory organs, but also in their muscular system.
 Conclusion. The muscular elements of the diaphragm have the pronounced and significant resistance to the state of hypoxia under conditions of limited ventilation of the respiratory tract. Ultrastructural and morphometric data, found on the 21st day after the modeling of partial tracheal stenosis, are not only of a compensatory and adaptive in nature, but also signs of pronounced disorders in the muscle fibers of the central part of the diaphragm in test animals.