Changes In Signatures Research Articles

Lipid signature changes of women with gestational diabetes mellitus in response to puerperal exclusive breastfeeding.

We here investigated whether lactation during puerperium could help to reverse the diabetogenic effect of gestation and further explored the lipid profiling changes upon breastfeeding. Thirty-five women diagnosed with GDM were recruited, and fasting plasma samples were collected at ~6 weeks postpartum. Maternal metabolic parameters were determined, and an untargeted lipidomic analysis was performed. The relationship between underlying lipidomic responses and lactation was explored. Improved glucose homeostasis and insulin sensitivity were observed in GDM women who adopted breastfeeding during the puerperium. Further lipidomics analysis revealed prominent correlations between lipid constitution changes and breastfeeding in women with GDM. A total of 766 lipid species were identified, 33 of which were found to be significantly altered in response to lactation. Significant associations between dysregulated lipids and maternal metabolic parameters were also shown. Subsequently, we identified a panel of three lipids that were strongly associated with breastfeeding, from which we constructed a predictive model with higher discriminating power. We generally revealed that lactation during puerperium appears to have favorable effects on diabetogenic risk factors for GDM women. We also discovered that lipidomic changes related to lactation could elucidate the mother's recovery from GDM pregnancy.

IL-1β promotes glutamate excitotoxicity: indications for the link between inflammatory and synaptic vesicle cycle in Ménière's disease.

Ménière's disease (MD) is a complex inner ear disorder characterized by a range of symptoms, with its pathogenesis linked to immune-related mechanisms. Our previous research demonstrated that IL-1β maturation and release can trigger cell pyroptosis, exacerbating the severity of the endolymphatic hydrops in a mouse model; however, the specific mechanism through which IL-1β influences MD symptoms remains unclear. This study conducted on patients with MD examined changes in protein signatures in the vestibular end organs (VO) and endolymphatic sac (ES) using mass spectrometry. Gene ontology and protein pathway analyses showed that differentially expressed proteins in the ES are closely related to adhesion, whereas those in the VO are related to synapse processes. Additionally, the study found elevated expression of Glutaminase (GLS) in the VO of MD patients compared to controls. Further investigations revealed that IL-1β increased glutamate levels by upregulating GLS expression in HEI-OC1 cells. Treatment with a GLS inhibitor or an IL-1β receptor antagonist alleviated auditory-vestibular dysfunction and reduced glutamate levels in mice with endolymphatic hydrops. These findings collectively suggest that imbalanced neurotransmitter release and immune responses contribute to the pathology of MD, potentially explaining the hearing loss and vertigo associated with the disease and offering new avenues for therapeutic interventions.

Multi-strain probiotic administration decreases necrotizing enterocolitis severity and alters the epigenetic profile in mice.

Probiotic administration may decrease the incidence of necrotizing enterocolitis (NEC) through mechanisms that are largely unknown. We investigated the effects of probiotics on intestinal epigenetics and assessed their effects on intestinal inflammation and motility using both ileum-predominant and combined ileo-colitis mouse NEC models. C57BL/6 J mice were gavage-fed a multi-strain probiotic from postnatal days 3-11, consisting of B. infantis, B. lactis, and S. thermophilus. From p8, mice were exposed to ileo-colitis NEC involving formula containing NEC bacteria and 0.5% DSS. DNA methylation was measured using the Infinium Methylation Assay. Gastrointestinal motility was assessed by 70 Kd FITC-dextran transit time. Probiotic colonization was measured in probiotic-fed mice by qPCR. Probiotic administration caused significant changes in the small intestine's epigenetic signature, a reduction in NEC severity, and improved intestinal motility. The effects of probiotics were more pronounced in the ileo-colitis NEC model. These findings shed light on the role of probiotics in two clinically relevant models of NEC, add additional insights into their underlying mechanism of action, and reveal unanticipated epigenetic modifications to the intestinal mucosa after their use. These findings shed light on the role of multi-strain probiotics in two clinically relevant animal models of NEC, and add additional insights into their underlying mechanism of action This study provides a new, clinically relevant model for the study of NEC including administration of 0.5% DSS, to include ileal dominant and ileo-colonic dominant phenotypes of the disease. These results reveal that clinically relevant strains of probiotic bacteria can exert epigenetic effects on the small intestine in mice, and can attenuate the epigenetic changes induced by NEC.

Deucravacitinib in Plaque Psoriasis: Laboratory Parameters Through 4 Years of Treatment in the Phase 3 POETYK PSO-1, PSO-2, and LTE Trials

Introduction: Deucravacitinib, an oral, selective, allosteric tyrosine kinase 2 inhibitor, is approved in multiple countries for treatment of adults with moderate to severe plaque psoriasis who are candidates for systemic therapy. Deucravacitinib was efficacious versus placebo and apremilast and was well tolerated in the global, 52-week, phase 3 POETYK PSO-1 (NCT03624127) and POETYK PSO-2 (NCT03611751) parent trials. At Week 52, patients could enroll in the ongoing POETYK long-term extension (LTE) (NCT04036435) trial and receive open-label deucravacitinib. Changes in blood laboratory parameters known to be associated with Janus kinase (JAK) 1,2,3 inhibitors were evaluated through 4 years of deucravacitinib treatment. Methods: Changes from baseline in lipid (cholesterol, triglycerides), chemistry (alanine aminotransferase [ALT], aspartate aminotransferase [AST], creatinine, creatine phosphokinase [CPK]), and hematology (hemoglobin, lymphocytes, neutrophils, platelets) parameters in the blood known to be affected by JAK1,2,3 inhibitors in clinical trials were evaluated through Week 208 (4 years; data cutoff, November 1, 2023). Treatment discontinuations due to laboratory abnormalities were assessed. Results: A total of 1519 patients received ≥1 deucravacitinib dose (total exposure, 4392.8 person-years); 1203 (79.2%) had ≥52 weeks and 542 (35.7%) had ≥208 weeks of continuous deucravacitinib exposure (median, 185 weeks). No trends or clinically meaningful mean changes from baseline were observed in any of the above laboratory parameters. In total, 3 patients discontinued treatment due to increased CPK, and 1 patient each discontinued due to lymphopenia, abnormal hepatic function, increased ALT, and increased AST. Discontinuations due to triglyceride elevations were not observed. Conclusion: In PSO-1/PSO-2/LTE, no trends or clinically meaningful mean changes from baseline were observed in lipid, chemistry, or hematology parameters, in contrast to signature changes (eg, increased cholesterol, creatinine, serum transaminases, CPK, cytopenias) observed with JAK1,2,3 inhibitors. Discontinuations due to laboratory abnormalities noted above were rare (n=7 events) through 4 years of deucravacitinib treatment. Results suggest deucravacitinib treatment does not warrant routine laboratory testing for all patients, in contrast with the requirements for JAK1,2,3 inhibitors, reflecting its selectivity for TYK2.

PINK1/Parkin-Mediated Mitophagy Ameliorates Mitochondrial Dysfunction in Lacrimal Gland Acinar Cells During Aging.

Aging alters the function of the lacrimal gland and disrupts the balance of the microenvironment on the ocular surface, eventually leading to aqueous-tear-deficient dry eye. Mitophagy has been reported to play an important role in aging, but the underlying mechanism remains unclear. The young (6 weeks) and middle-aged (12months) male C57BL/6J mice were used in this study, and mitophagy agonist rapamycin and inhibitor Mdivi-1 were used in in vivo experiments. Hematoxylin and eosin, Masson, Oil Red O, and reactive oxygen species (ROS) staining were used to detect histological changes and lipids in lacrimal gland. Changes in the expression of proteins were identified by Western blotting of lacrimal gland lysates. Transmission electron microscopy and immunofluorescence staining were used to assess mitophagy. The single-cell RNA sequencing (scRNA-seq) and bioinformatics analyses were used to detect transcription signature changes during aging. In this study, we discovered that aging increased oxidative stress, which increased apoptosis, and generated ROS in acinar epithelial cells. Furthermore, activation of PINK1/Parkin-mediated mitophagy by rapamycin reduced lacrimal gland ROS concentrations and prevented aging-induced apoptosis of acinar cells, thereby causing histological alterations, microstructural degradation, and increasing tear secretion associated with ROS accumulation. By contrast, Mdivi-1 aggregates mitochondrial function and thereafter leads to lacrimal gland function impairment by inhibiting mitochondrial fission and giving rise to mitophagy. Overall, our findings suggested that aging could impair mitochondrial function of acinar cells, and age-related alterations may be treated with therapeutic approaches that enhance mitophagy while maintaining mitochondrial function.

Fecal and Sputum Microbiota and Treatment Response in Patients with Mycobacterium abscessus Pulmonary Disease.

The microbiota is a potential source of biomarkers for clinical outcomes in chronic respiratory conditions, but its role in Mycobacterium abscessus pulmonary disease (PD) remains unexplored. We aimed to identify microbial signatures in fecal and sputum microbiotas associated with treatment response in patients with M. abscessus PD. We conducted a cohort study prospectively enrolling patients undergoing antibiotic treatment for M. abscessus PD. Fecal and sputum samples were collected before, and 2 weeks and 6 months after, treatment initiation. 16S rRNA amplicon sequencing approach was used to characterize the microbiotas. After categorizing patients as early treatment responders and non-responders based on sputum culture results at 2 weeks, we elucidated the differences in their diversity and composition of microbiotas. Among 32 patients enrolled, 27 patients (median 66 years, 85.2% women, 48.1% with subspecies abscessus) were included for microbiota analysis. Fifteen patients (55.6%) achieved negative conversion at 2 weeks, which was maintained in 14 (93.3%) after 6 months. Alpha-diversity of the fecal microbiota after 2 weeks of treatment decreased significantly in responders, but not in non-responders (P=0.029). Increased abundance of Eubacterium hallii group in baseline fecal microbiota was indicative of unresponsiveness to antibiotics, whereas an increase in Enterococcus in fecal microbiota at week 2 was linked with favorable response. Increased abundance of Burkholderia-Caballeronia-Paraburkholderia and Porphyromonas in baseline, and decreased abundance of Rothia in week 2 sputum microbiota were also associated with good treatment response. In M. abscessus PD, changes in microbial diversity and compositional signatures vary with treatment response.

Calcium has a direct effect on thick filament activation in porcine myocardium.

Sarcomere activation in striated muscle requires both thin filament-based and thick filament-based activation mechanisms. Recent studies have shown that myosin heads on the thick filaments undergo OFF to ON structural transitions in response to calcium (Ca2+) in permeabilized porcine myocardium in the presence of a small molecule inhibitor that eliminated active force. The changes in X-ray diffraction signatures of OFF to ON transitions were interpreted as Ca2+ acting to activate the thick filaments. Alternatively, Ca2+ binding to troponin could initiate a Ca2+-dependent crosstalk from the thin filament to the thick filament via interfilament connections such as the myosin binding protein-C. Here, we exchanged native troponin in permeabilized porcine myocardium for troponin containing the cTnC D65A mutation, which disallows the activation of troponin through Ca2+ binding to determine if Ca2+-dependent thick filament activation persists in the absence of thin filament activation. After the exchange protocol, over 95% of the Ca2+-activated force was eliminated. Equatorial intensity ratio increased significantly in both WT and D65A exchanged myocardium with increasing Ca2+ concentration. The degree of helical ordering of the myosin heads decreased by the same amount in WT and D65A myocardium when Ca2+ concentration increased. These results are consistent with a direct effect of Ca2+ in activating the thick filament rather than an indirect effect due to Ca2+-mediated crosstalk between the thick and thin filaments.

Symmetric teleparallel gravity with variable deceleration parameter

In this paper, our investigation focuses on the cosmic history in modified [Formula: see text] gravity, a different theory that describes the gravitational force using a non-metricity scalar. The equations of the theory are solved by assuming a parametric form for the deceleration parameter. The parameters of the model are estimated by using the Cosmic Chronometer dataset. A number of parameters, like the deceleration parameter, whose signature changes with redshift and shows typical behavior in late-time cosmology, are subject of our analysis. We also show the evolution of other parameters, such as the equation of state parameter and energy density. The parametrization approach used here in [Formula: see text] modified gravity provides a better description of the late-time cosmic evolution without dark energy.

Signature-based IaaS Performance Change Detection

We propose a novel change detection framework to identify changes in the long-term performance behavior of an IaaS service. An IaaS service’s long-term performance behavior is represented by an IaaS performance signature. The proposed framework leverages time series similarity measures and a sliding window technique to detect changes in IaaS performance signatures. We introduce a new IaaS performance noise model that enables the proposed framework to distinguish between performance noise and actual changes in performance. The proposed framework utilizes a novel Signal-to-Noise Ratio (SNR) based approach to detect changes when prior knowledge about performance noise is available. A set of experiments is conducted using real-world datasets to demonstrate the effectiveness of the proposed change detection framework.

Chronic interferon-stimulated gene transcription promotes oncogene-induced breast cancer.

The MRE11 complex (comprising MRE11, RAD50, and NBS1) is integral to the maintenance of genome stability. We previously showed that a hypomorphic Mre11 mutant mouse strain (Mre11 ATLD1/ATLD1 ) was highly susceptible to oncogene-induced breast cancer. Here we used a mammary organoid system to examine which MRE11-dependent responses are tumor-suppressive. We found that Mre11 ATLD1/ATLD1 organoids exhibited an elevated interferon-stimulated gene (ISG) signature and sustained changes in chromatin accessibility. This Mre11 ATLD1/ATLD1 phenotype depended on DNA binding of a nuclear innate immune sensor, IFI205. Ablation of Ifi205 in Mre11 ATLD1/ATLD1 organoids restored baseline and oncogene-induced chromatin accessibility patterns to those observed in WT. Implantation of Mre11 ATLD1/ATLD1 organoids and activation of the oncogene led to aggressive metastatic breast cancer. This outcome was reversed in implanted Ifi205 -/- Mre11 ATLD1/ATLD1 organoids. These data reveal a connection between innate immune signaling and tumor development in the mammary epithelium. Given the abundance of aberrant DNA structures that arise in the context of genome instability syndromes, the data further suggest that cancer predisposition in those contexts may be partially attributable to chronic innate immune transcriptional programs.

Locoregional event or dyssynchronous distant metastasis: clinicopathological and molecular analysis of contralateral axillary lymph node metastasis in breast cancer patients.

Contralateral axillary lymph node metastasis (CAM) is a rare clinical condition in patients with breast cancer (BC). CAM can be either a locoregional event or a distant metastasis. Molecular application for clonal evolution in BC has not been reported in CAM cases. We studied six patients with CAM with clinical, pathological and/or molecular evidence of distant metastasis; those patients had poor outcomes. Two cases with molecular analysis of paired primary and CAM established clonal evolution of the CAM with its corresponding primary with additional molecular alteration, increased tumour mutation burden, and copy number variations (CNVs) in the CAMs. Four cases containing alterations from genes potentially modulate chromatin organization, supporting chromatin and subsequent transcriptional signature changes are essential in CAM. Molecular analysis is critical to establish the connection between CAM and its primary counterpart. Distant CAM shows clonal evolution compared with its corresponding primary with additional molecular alterations, increased mutation burden and/or copy number variations. CAM should be evaluated individually and handled in a personalized fashion. Evidence of a true metastatic CAM can be supported by distant metastasis to other organs, specific morphological features and/or clonal evolution.

Detection and characterization of colorectal cancer by autofluorescence lifetime imaging on surgical specimens.

Colorectal cancer (CRC) ranks among the most prevalent malignancies worldwide, driving a quest for comprehensive characterization methods. We report a characterization of the ex vivo autofluorescence lifetime fingerprint of colorectal tissues obtained from 73 patients that underwent surgical resection. We specifically target the autofluorescence characteristics of collagens, reduced nicotine adenine (phosphate) dinucleotide (NAD(P)H), and flavins employing a fiber-based dual excitation (375nm and 445nm) optical imaging system. Autofluorescence-derived parameters obtained from normal tissues, adenomatous lesions, and adenocarcinomas were analyzed considering the underlying clinicopathological features. Our results indicate that differences between tissues are primarily driven by collagen and flavins autofluorescence parameters. We also report changes in the autofluorescence parameters associated with NAD(P)H that we tentatively attribute to intratumoral heterogeneity, potentially associated to the presence of distinct metabolic subpopulations. Changes in autofluorescence signatures of malignant tumors were also observed with lymphatic and venous invasion, differentiation grade, and microsatellite instability. Finally, we characterized the impact of radiative treatment in the autofluorescence fingerprints of rectal tissues and observed a generalized increase in the mean lifetime of radiated adenocarcinomas, which is suggestive of altered metabolism and structural remodeling. Overall, our preliminary findings indicate that multiparametric autofluorescence lifetime measurements have the potential to significantly enhance clinical decision-making in CRC, spanning from initial diagnosis to ongoing management. We believe that our results will provide a foundational framework for future investigations to further understand and combat CRC exploiting autofluorescence measurements.

Effect of Heat Stress on the Expression of Circulating Cyto(chemo)kine and Inflammatory Markers in Broiler Chickens Selected for High- or Low-water Efficiency.

Water scarcity is a current, significant global concern that will only increase under the pressure of climate change. Improving water efficiency of poultry is a new and promising area to help temper agriculture's future impact on fresh water availability. Here, we explored the effects of acute heat stress (HS) on circulating stress and inflammatory markers in 2 lines of broilers divergently selected for water efficiency. Male chicks from low (LWE) and high water efficient (HWE) lines were raised in 12 environmental chambers (2 pens/chamber, 6 chambers/line, 20 birds/pen) under normal conditions until day 28. On day 29, birds were subjected to thermoneutral (TN, 25 °C) or HS (36 °C) conditions, resulting in four treatments (2 lines × 2 environmental conditions). After 3 h of HS, whole blood was collected (8 birds per line × environment) and analyzed for target gene expression and plasma cytokine levels. Data were analyzed by 2-way ANOVA, with line, environment, and their interaction as main factors, and means were compared using Tukey's multiple range test. Gene expression of heat shock protein (HSP) 27, HSP70, interleukin (IL)-6, IL-18, c-reactive protein (CRP), tumor necrosis factor-α (TNFα), C-C motif chemokine ligand 4 (CCL4), CCL20, nucleotide-binding domain, leucine-rich repeat (NLR) family pyrin domain containing 3 (NLRP3), NLR family CARD domain containing 5 (NLRC5), and NLR family member X1 (NLRX1) were increased by HS, with no differences between the lines. HSP70, IL-10, and NLRC3 were lower in the HWE as compared to the LWE lines. Additionally, there were interactive effects between line and environment for HSP90, IL-4, and CCL4, where HS induced HSP90 expression in the LWE only, and IL-4 and CCL4 in HWE only. Arginine vasopressin (AVP) gene expression was significantly lower in the whole blood of the HWE line; however, plasma protein levels were not different. Overall, most of the effects seen on cyto (chemokines) and inflammatory markers were due to acute HS, with only a few genes differentially regulated between the lines. This likely indicates that the divergent selection for water efficiency for four generations did not elicit changes in inflammation and stress molecular signatures.

Analysis of the Biennial Productivity of Arabica Coffee with Google Earth Engine in the Northeast Region of São Paulo, Brazil

Numerous challenges are associated with the classification of satellite images of coffee plantations. The spectral similarity with other types of land use, variations in altitude, topography, production system (shaded and sun), and the change in spectral signature throughout the phenological cycle are examples that affect the process. This research investigates the influence of biennial Arabica coffee productivity on the accuracy of Landsat-8 image classification. The Google Earth Engine (GEE) platform and the Random Forest algorithm were used to process the annual and biennial mosaics of the Média Mogiana Region, São Paulo (Brazil), from 2017 to 2023. The parameters evaluated were the general hits of the seven classes of land use and coffee errors of commission and omission. It was found that the seasonality of the plant and its development phases were fundamental in the quality of coffee classification. The use of biennial mosaics, with Landsat-8 images, Brightness, Greenness, Wetness, SRTM data (elevation, aspect, slope), and LST data (Land Surface Temperature) also contributed to improving the process, generating a classification accuracy of 88.8% and reducing coffee omission errors to 22%.

Elucidating the Fate of the Organochlorine Pesticide Chlordecone under Abiotic Reductive and Oxidative Processes: Kinetics, Transformation Products, and C vs Cl Isotope Fractionation.

Pollution of French West Indies (FWI) soils by the organochlorine pesticide chlordecone poses environmental and societal concerns due to its long-term persistence. Assessing chlordecone degradation remains challenging due to analytical constraints to identify transformation products. Here, multielement compound-specific isotope analysis (ME-CSIA) was used to identify changes in stable isotope signatures of chlordecone produced during abiotic transformation reactions under reducing and oxidative conditions. Effective chlordecone transformation was shown in reactions with zerovalent iron (ZVI), vitamin B12 and sodium sulfide (VSS), alkaline ascorbic acid (AA), and sodium persulfate activated by microwave irradiation (MWPS). Significant enrichment of 13C and 37Cl was observed in all abiotic reactions, with εC,bulk and εCl,bulk values ranging from -4.3 ± 0.4‰ to -2.3 ± 0.2‰ and from -2.6 ± 0.4‰ to -1.3 ± 0.3‰, respectively. Distinct mechanisms were evidenced in dual isotope plots, resulting in Λ values of 1.17 ± 0.28 for ZVI, 1.26 ± 0.50 for VSS, 2.06 ± 0.30 for AA, and 2.90 ± 0.50 for MWPS. Two major products were formed, 10-monohydrochlordecone and 8-monohydrochlordecone. Cl-CSIA data suggested that the first Cl substitution at the C10-position likely produced secondary Cl isotope effects (via nucleophilic substitution). Overall, results suggest that ME-CSIA can help quantify in situ chlordecone degradation, distinguishing between different ongoing degradation mechanisms and fingerprinting pollutant sources from chlordecone formulations (Curlone).

Detection Methods for Pine Wilt Disease: A Comprehensive Review.

Pine wilt disease (PWD), caused by the nematode Bursaphelenchus xylophilus, is a highly destructive forest disease that necessitates rapid and precise identification for effective management and control. This study evaluates various detection methods for PWD, including morphological diagnosis, molecular techniques, and remote sensing. While traditional methods are economical, they are limited by their inability to detect subtle or early changes and require considerable time and expertise. To overcome these challenges, this study emphasizes advanced molecular approaches such as real-time polymerase chain reaction (RT-PCR), droplet digital PCR (ddPCR), and loop-mediated isothermal amplification (LAMP) coupled with CRISPR/Cas12a, which offer fast and accurate pathogen detection. Additionally, DNA barcoding and microarrays facilitate species identification, and proteomics can provide insights into infection-specific protein signatures. The study also highlights remote sensing technologies, including satellite imagery and unmanned aerial vehicle (UAV)-based hyperspectral analysis, for their capability to monitor PWD by detecting asymptomatic diseases through changes in the spectral signatures of trees. Future research should focus on combining traditional and innovative techniques, refining visual inspection processes, developing rapid and portable diagnostic tools for field application, and exploring the potential of volatile organic compound analysis and machine learning algorithms for early disease detection. Integrating diverse methods and adopting innovative technologies are crucial to effectively control this lethal forest disease.

Unveiling Lipidomic Alterations in Metabolic Syndrome: A Study of Plasma, Liver, and Adipose Tissues in a Dietary-Induced Rat Model

Metabolic syndrome (MetS) is a complex condition characterized by fat accumulation, dyslipidemia, impaired glucose control and hypertension. In this study, rats were fed a high-fat high-fructose (HFF) diet in order to develop MetS. After ten weeks, the dietary-induced MetS was confirmed by higher body fat percentage, lower HDL-cholesterol and increased blood pressure in the HFF-fed rats compared to the normal-fed control animals. However, the effect of MetS development on the lipidomic signature of the dietary-challenged rats remains to be investigated. To reveal the contribution of specific lipids to the development of MetS, the lipid profiling of rat tissues particularly susceptible to MetS was performed using untargeted UHPLC-QTOF-MS/MS lipidomic analysis. A total of 37 lipid species (mainly phospholipids, triglycerides, sphingolipids, cholesterol esters, and diglycerides) in plasma, 43 lipid species in liver, and 11 lipid species in adipose tissue were identified as dysregulated between the control and MetS groups. Changes in the lipid signature of selected tissues additionally revealed systemic changes in the dietary-induced rat model of MetS.

Sputum Metabolomic Signature and Dynamic Change of Cough Variant Asthma.

Cough variant asthma (CVA), a common reason for chronic cough, is a globally prevalent and burdensome condition. The heterogeneity of CVA and a lack of knowledge concerning the exact molecular pathogenesis has hampered its clinical management. This study presented the first sputum metabolome of CVA patients, revealed the dynamic change during treatment, and explored biomarkers related to the occurrence and treatment response of CVA. We found arginine biosynthesis, purine metabolism, and pyrimidine metabolism pathways were enriched in CVA compared to healthy controls. Part of metabolic disturbances could be reversed by anti-asthmatic medication. The levels of dipeptides/tripeptides (alanyltyrosine, Gly-Tyr-Ala, Ala-Leu, and Thr-Leu) were significantly associated with sputum Neu% or Eos% of CVA patients. Differential metabolites pre-treatment between effective and ineffective groups enriched in purine metabolism, thiamine metabolism, and arginine metabolism. 2-isopropylmalate was down-regulated in CVA patients and increased after treatment, and effective group had a lower 2-isopropylmalate level pre-treatment. Random forest and logistic regression models identified glutathione, thiamine phosphate, alanyltyrosine, and 2'-deoxyadenosine as markers for distinguishing CVA from healthy controls (all AUC > 0.8). Thiamine phosphate might also be promising for predicting therapy responsiveness (AUC = 0.684). These findings implied that disturbed mitochondrial energy metabolism and imbalanced oxidation-reduction homeostasis probably underlay the metabolic pathogenesis of CVA.

Sources of lead in a Tibetan glacier since the Stone Age

The Tibetan Plateau glaciers, among the world’s most remote and pristine places, provide water to millions and play a vital environmental role. We measured the lead isotopic composition in a dusty ice core from the Guliya ice cap in northwest Tibet, from approximately 36 thousand years Before Present (Stone Age) to 2015, to determine the onset and sources of anthropogenic lead. Despite the dust-laden nature of the core, a clear change in the lead isotope signature to below Stone Age levels started in 1949 followed by a rapid decrease in 1960 and an even more rapid decrease in 1974 indicating the first emergence of anthropogenic lead. Accurate isotopic lead measurements allowed us to better, and more sensitively, quantify sources using a Bayesian mixing model. Chinese gasoline was the primary anthropogenic source surpassing natural contributions in the 2000s until 2007 when emissions from leaded gasoline decreased and those from coal and lead-zinc ores increased.

Abstract B078: A comprehensive spatial atlas of neoadjuvant chemoradiation therapy in resected pancreatic cancer identifies cellular & microenvironmental determinants of persister populations

Abstract Background The molecular pathways involved in the response to radiation therapy (RT) in pancreatic ductal adenocarcinoma (PDAC) remain poorly understood. Despite extensive molecular stratification efforts, improvements in molecularly informed RT-based therapeutic strategies in the neoadjuvant setting have been limited. This study aims to elucidate the adaptive mechanisms and interactions within PDAC to identify new combinatorial therapeutic targets with RT. MethodsWe constructed a high-resolution molecular landscape of the cellular subtypes and spatial communities that constitute PDAC. Single-cell RNA sequencing (scRNA- seq) was performed on 16 PDAC biopsies of matched pre- and post-treatment samples from a Phase I/II dose-escalation clinical trial of pancreatic stereotactic body radiation therapy (SBRT). Additionally, Visium spatial transcriptomics (ST) was conducted on biopsies from primary PDAC patients collected at the time of surgery. These patients received either no neoadjuvant therapy (n = 8) or neoadjuvant chemoradiation (chemoRT) (n = 20). Cell type profiles were determined from scRNA-seq to compare changes in cell type proportions and signatures before and after RT. From these profiles, we employed robust cell type decomposition to analyze cell type signatures in our ST dataset. ResultsChemoRT induced several significant effects compared to controls within the tumor microenvironment, including an increase in the proportion of myofibroblasts, specifically senescent cancer-associated fibroblasts (CAFs), with signatures consistent with immune cell dysfunction. We observed an increase in CD8 and CD4 effector memory cells with RT; however, this occurred alongside a rise in immunosuppressive alternatively activated tumor-associated macrophages. Additionally, RT upregulated pathways related to HIF, cytokine production, B cell proliferation, and negative regulation of lymphocytes. Patients with increased infiltration of NK, memory B, and CD8 effector memory cells demonstrated improved overall survival outcomes. Inference of copy number variations enabled us to identify cancer subclones as either responsive or resistant in matched pre and post RT biopsies. Resistance was characterized by augmented hypoxia, KRAS activation, epithelial- mesenchymal transition, and interferon-gamma response signaling. Conversely, responders exhibited increased oxidative phosphorylation signaling and pathway enrichment associated with cell proliferation and cell cycle progression. Interestingly, RT induced a decrease in cancer cells characterized as harboring a chemoresistant basal-like molecular subtype. ConclusionThrough both longitudinal and therapy stratified tumor biopsies, we were able to observe significant selection pressures on stromal and cancer cells following RT. This includes upregulation of innate and adaptive immune pathways with a compensatory immunosuppressive response driven by myeloid cells and CAFs. This may provide opportunities for development of clinical trials to therapeutically target specific cellular phenotypes and their interactions. Citation Format: Vincent Bernard, Galia Jacobson, Kimal Rajapakshe, Jimin Min, Guangsheng Pei, Daniel Lin, Ayush Suresh, Dadi Jiang, Ching-Wei Tzeng, Manoop S Bhutani, Linghua Wang, Paola A Guerrero, Ethan B Ludmir, Albert C Koong, Anirban Maitra, Cullen M Taniguchi, Eugene J Koay. A comprehensive spatial atlas of neoadjuvant chemoradiation therapy in resected pancreatic cancer identifies cellular & microenvironmental determinants of persister populations [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B078.