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In the modern "omics" era, measurement of the human exposome is a critical missing link between genetic drivers and disease outcomes. High-resolution mass spectrometry (HRMS), routinely used in proteomics and metabolomics, has emerged as a leading technology to broadly profile chemical exposure agents and related biomolecules for accurate mass measurement, high sensitivity, rapid data acquisition, and increased resolution of chemical space. Non-targeted approaches are increasingly accessible, supporting a shift from conventional hypothesis-driven, quantitation-centric targeted analyses toward data-driven, hypothesis-generating chemical exposome-wide profiling. However, HRMS-based exposomics encounters unique challenges. New analytical and computational infrastructures are needed to expand the analysis coverage through streamlined, scalable, and harmonized workflows and data pipelines that permit longitudinal chemical exposome tracking, retrospective validation, and multi-omics integration for meaningful health-oriented inferences. In this article, we survey the literature on state-of-the-art HRMS-based technologies, review current analytical workflows and informatic pipelines, and provide an up-to-date reference on exposomic approaches for chemists, toxicologists, epidemiologists, care providers, and stakeholders in health sciences and medicine. We propose efforts to benchmark fit-for-purpose platforms for expanding coverage of chemical space, including gas/liquid chromatography-HRMS (GC-HRMS and LC-HRMS), and discuss opportunities, challenges, and strategies to advance the burgeoning field of the exposome.

Abstract Deep single-cell multi-omic profiling offers a promising approach to understand and overcome drug resistance in relapsed or refractory (rr) acute myeloid leukemia (AML). Here, we combine single-cell ex vivo drug profiling (pharmacoscopy) with single-cell and bulk DNA, RNA, and protein analyses, alongside clinical data from 21 rrAML patients. Unsupervised data integration reveals reduced ex vivo response to the Bcl-2 inhibitor venetoclax (VEN) in patients treated with both a hypomethylating agent (HMA) and VEN, compared to those pre-exposed to chemotherapy or HMA alone. Integrative analysis identifies both known and unreported mechanisms of innate and treatment-related VEN resistance and suggests alternative treatments, like targeting increased proliferation with the PLK inhibitor volasertib. Additionally, high CD36 expression in VEN-resistant blasts associates with sensitivity to CD36-targeted antibody treatment ex vivo. This study demonstrates how single-cell multi-omic profiling can uncover drug resistance mechanisms and treatment vulnerabilities, providing a valuable resource for future AML research.

Although home visiting is growing as a service for families with young children, the field does not adequately prepare the home visiting workforce, and higher education courses on home visiting are rare. Many home visitors are prepared through higher education as teachers, social workers, or nurses, which provides knowledge but few of the skills needed to collaborate with families to support their children's development, revealing a need for focused pre-service preparation for home visiting. We conducted a qualitative study to (1) describe the present state of preparation in higher education and (2) propose recommendations for strengthening home visitor preparation via higher education. Focus groups (N = 43) were conducted at conferences that included some focus on early childhood home visiting. Individual interviews (N = 11) were conducted parallel to focus groups. Participants were faculty and administrators in higher education or home visiting related professionals. Using thematic analysis, three major themes surfaced: (1) learning, training, and awareness in higher education; (2) blending of a myriad of skills in home visiting; and (3) unification and support needs. Our findings emphasize the need for higher education to provide professional preparation for careers in home visiting. We offer recommendations to meet this need. [This paper was written with the Collaborative for Understanding the Pedagogy of Infant/Toddler Development (CUPID).]

Teacher self-efficacy (TSE) changes according to context. Limited research has been conducted to understand how TSE can vary in relation to student characteristics or the student-teacher relationship (STR) in preschool. The aims of the current study were to 1) examine student-specific TSE variability among monolingual English-speaking and Spanish-speaking dual language learners (DLLs) and 2) examine the extent to which STR quality moderates the relationship between student language and student-specific TSE. Results demonstrated that when controlling for closeness in the STR, teachers felt higher levels of student-specific TSE in the domains of instructional support and student engagement for English-speaking students versus DLLs. However, teachers reported equal levels of student-specific TSE in the domains of behavior management and emotional support irrespective of student language. Secondly, STR quality did not significantly moderate relationships between language and student-specific TSE. Limitations and future research directions are discussed.

Abstract Background Several legacy and emerging per- and polyfluoroalkyl substances (PFAS) have been regulated around the world. There is growing concern over the proliferation of alternative PFAS, as well as PFAS precursors. Biomonitoring data for PFAS are critical for assessing exposure and human health risk. Methods We collected serum samples from 289 adult female participants in a 2018–2021 follow-up study of the Maternal-Infant Research on Environmental Chemicals (MIREC) Canadian pregnancy cohort. Samples were analyzed for 40 PFAS using ultra-performance liquid chromatography–tandem mass spectrometry. For those compounds with > 50% detection, as well as the sum of these compounds, we describe serum concentrations and patterns of exposure according to sociodemographic and obstetrical history characteristics. Results 17 out of 40 PFAS were detected in > 50% of samples with 7 of these detected in > 97% of samples. Median [95th percentile] concentrations (µg/L) were highest for PFOS (1.62 [4.56]), PFOA (0.69 [1.52]), PFNA (0.38 [0.81]), and PFHxS (0.33 [0.92]). Geometric mean concentrations of PFOA and PFHxS were approximately 2-fold lower among those with more children (≥ 3 vs. 1), greater number of children breastfed (≥ 3 vs. ≤ 1), longer lifetime duration of breastfeeding (> 4 years vs. ≤ 9 months), and shorter time since last pregnancy (≤ 4 years vs. > 8 years). We observed similar patterns for PFOS, PFHpS, and the sum of 17 PFAS, though the differences between groups were smaller. Concentrations of PFOA were higher among “White” participants, while concentrations of N-MeFOSE, N-EtFOSE, 7:3 FTCA, and 4:2 FTS were slightly higher among participants reporting a race or ethnicity other than “White”. Concentrations of legacy, alternative, and precursor PFAS were generally similar across levels of age, education, household income, body mass index, and menopausal status. Conclusions We report the first Canadian biomonitoring data for several alternative and precursor PFAS. Our findings suggest that exposure to PFAS, including several emerging alternatives, may be widespread. Our results are consistent with previous studies showing that pregnancy and breastfeeding are excretion pathways for PFAS.

Abstract Background Active transport– for example walking and bicycling to travel from place to place– may improve physical fitness and health and mitigate climate change if it replaces motorised transport. The aim of this study is to analyse the active transport behaviour of adults living in Germany, to investigate differences among population groups and to determine whether climate protection is a frequent motive for this behaviour. Methods This study uses self-reported data of 4,971 adults who participated in a national health survey (German Health Update 2021), which was conducted as a telephone survey from July to December 2021. Associations between active transport behaviour and corresponding motives with sociodemographic and health-related variables were analysed using logistic regression models. Results Of the adult population, 83% use active transport at least once a week. The frequency and duration of walking per week are significantly higher than those for bicycling (walking 214 min/week; bicycling 57 min/week). Those with a lower education level are less likely to practise active transport than those with a higher education level. Furthermore, women are less likely to use a bicycle for transport than men. Among those practising active transport, the most frequently mentioned motive is “is good for health” (84%) followed by “to be physically active” (74%) and “is good for the climate/environment” (68%). Women and frequent bicyclists (at least 4 days/week) mention climate protection as a motive more often than men and those bicycling occasionally. Conclusions The improvement of active transport, especially among people with lower education and women (for bicycling), may benefit from better insights into motives and barriers. Climate protection is an important motivator for practising active transport within the adult population living in Germany and should therefore have greater emphasis in behavioural change programmes.

Both professional and classroom-based scientific communities develop and test explanatory models of the natural world. For students to take up models as tools for sensemaking, practice must be agentive (where students use and revise models "for" specific purposes) and conceptually productive (where students make progress on their ideas). In this paper, we explore principles to support agentive and conceptually productive modeling. One is that models can "do work"; that is, participate in students' sensemaking by offering resources, making gaps visible, or pushing back on modelers' understandings. A second is that working across, and seeking to align, multiple models--what we explain as "interlocking" models--supports models to do work. A third is that modeling activity can support fine-grained conceptual progress. We detail how we used these ideas to guide and refine the design of a fifth-grade investigation into the conservation of matter across phase change. We identify four ways that models participated in students' sensemaking as they interlocked: by providing "contradictions, constraints, representational surplus," and "gaps" for students to engage with. We discuss how designing for models to be co-participants in sense-making and to interlock can provide productive paths forward for curriculum designers, researchers, and teachers.

Few studies have considered household interventions for reducing endocrine disrupting chemical (EDC) exposures. We conducted a secondary analysis of a randomized controlled trial, originally designed to reduce lead exposure, to evaluate if the intervention lowered EDC exposures in young children. Study participants were children from the Cincinnati, Ohio area (n = 250, HOME Study). Prenatally, families received a housing intervention that included paint stabilization and dust mitigation, or as a control, injury prevention measures. At 24-months, we measured organophosphate esters (OPEs) and phthalates or their metabolites in dust and urine. We measured perfluoroalkyl substances (PFAS) in dust and serum at 24- and 36-months, respectively. We assessed associations between dust and biomarker EDCs using Spearman correlations, characterized EDC mixtures via principal components analysis, and investigated treatment effects using linear regression. To mitigate selection bias, we fit statistical models using inverse probability of retention weights. Correlations between dust EDCs and analogous biomarkers were weak-to-moderate (ρ’s ≤ 0.3). The intervention was associated with 23 % (95 % CI: −38, −3) lower urinary DEHP metabolites and, in a per-protocol analysis, 34 % lower (95 % CI: −55, −2) urinary MBZP. Additionally, among Black or African American children, the intervention was associated with lower serum concentrations of several PFAS (e.g., −42 %; 95 % CI: −63, −8 for PFNA). Household interventions that include paint stabilization and dust mitigation may reduce childhood exposures to some phthalates and PFAS in Blacks/African Americans. These findings highlight the need for larger studies with tailored and sustained housing interventions.

Abstract Introduction Plaque psoriasis is a common, often debilitating, chronic autoimmune inflammatory skin disease. Moderate-to-severe forms of psoriasis can be treated with biologics such as anti-interleukin and anti-tumor necrosis factor antibodies. We aimed to investigate treatment discontinuation among patients with psoriasis who initiated biologic treatment. Methods We conducted a retrospective, non-interventional cohort study based on anonymized claims data from the German statutory health insurance which covered the years from 2016 to 2021. We included adult patients with psoriasis who initiated biologic treatment in drug-specific cohorts. Over a 365-day follow-up period, we assessed the frequencies and the time until treatment discontinuation for different biologics. Differences in discontinuation rates were compared using a multivariate Cox proportional hazards model. Results A total of 2565 patients with psoriasis who initiated treatment with secukinumab (n = 612), adalimumab (n = 454), guselkumab (n = 354), ixekizumab (n = 259), ustekinumab (n = 241), tildrakizumab (n = 205), brodalumab (n = 166), risankizumab (n = 145), etanercept (n = 91), certolizumab (n = 29), and infliximab (n = 9) were included. A total of 1290 patients (50.29%) discontinued treatment during the follow-up period, ranging from 30.34% (risankizumab) to 69.23% (etanercept). Median time until discontinuation of treatment ranged from 102 days (etanercept) to 208 days (risankizumab). Once the biologic treatment was discontinued, 45.05% of patients restarted the treatment with the same agent, 23.10% of patients switched to another biologic, and 31.86% received no further biologic agent. Compared to patients treated with risankizumab, the treatment discontinuation rate was significantly higher (p

Abstract Controlled assembly of a protein shell around a viral genome is a key step in the life cycle of many viruses. Here we report a strategy for regulating the co-assembly of nonviral proteins and nucleic acids into highly ordered nucleocapsids in vitro. By fusing maltose binding protein to the subunits of NC-4, an engineered protein cage that encapsulates its own encoding mRNA, we successfully blocked spontaneous capsid assembly, allowing isolation of the individual monomers in soluble form. To initiate RNA-templated nucleocapsid formation, the steric block can be simply removed by selective proteolysis. Analyses by transmission and cryo-electron microscopy confirmed that the resulting assemblies are structurally identical to their RNA-containing counterparts produced in vivo. Enzymatically triggered cage formation broadens the range of RNA molecules that can be encapsulated by NC-4, provides unique opportunities to study the co-assembly of capsid and cargo, and could be useful for studying other nonviral and viral assemblies.

Abstract Cytokine-based therapeutics have been shown to mediate objective responses in certain tumor entities but suffer from insufficient selectivity, causing limiting toxicity which prevents dose escalation to therapeutically active regimens. The antibody-based delivery of cytokines significantly increases the therapeutic index of the corresponding payload but still suffers from side effects associated with peak concentrations of the product in blood upon intravenous administration. Here we devise a general strategy (named “Intra-Cork”) to mask systemic cytokine activity without impacting anti-cancer efficacy. Our technology features the use of antibody-cytokine fusions, capable of selective localization at the neoplastic site, in combination with pathway-selective inhibitors of the cytokine signaling, which rapidly clear from the body. This strategy, exemplified with a tumor-targeted IL12 in combination with a JAK2 inhibitor, allowed to abrogate cytokine-driven toxicity without affecting therapeutic activity in a preclinical model of cancer. This approach is readily applicable in clinical practice.

Abstract Randomized controlled trials (RCTs) are the gold standard to establish the benefit-risk ratio of novel drugs. However, the evaluation of mature results often takes many years. We hypothesized that the addition of Bayesian inference methods at interim analysis time points might accelerate and enforce the knowledge that such trials may generate. In order to test that hypothesis, we retrospectively applied a Bayesian approach to the HOVON 132 trial, in which 800 newly diagnosed AML patients aged 18 to 65 years were randomly assigned to a “7 + 3” induction with or without lenalidomide. Five years after the first patient was recruited, the trial was negative for its primary endpoint with no difference in event-free survival (EFS) between experimental and control groups (hazard ratio [HR] 0.99, p = 0.96) in the final conventional analysis. We retrospectively simulated interim analyses after the inclusion of 150, 300, 450, and 600 patients using a Bayesian methodology to detect early lack of efficacy signals. The HR for EFS comparing the lenalidomide arm with the control treatment arm was 1.21 (95% CI 0.81–1.69), 1.05 (95% CI 0.86–1.30), 1.00 (95% CI 0.84–1.19), and 1.02 (95% CI 0.87–1.19) at interim analysis 1, 2, 3 and 4, respectively. Complete remission rates were lower in the lenalidomide arm, and early deaths more frequent. A Bayesian approach identified that the probability of a clinically relevant benefit for EFS (HR

Somatostatin receptor type 2 (SSTR2) is one of the five subtypes of somatostatin receptors and is overexpressed on the surface of most gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs), pituitary tumors, paraganglioma, and meningioma, as well as hepatocellular carcinoma and breast cancer. Chimeric antigen receptor (CAR) T-cells are genetically engineered to express an artificial, T-cell activating binder, leading upon ligation to biocidal activity against target-antigen expressing cells. Adaptor-CAR T-cells recognize, via the CAR, a tag on an antigen-binding molecule, building an activating bridge between the CAR and the target cell. We hypothesized that a novel fluorescent-peptide antagonist of SSTR2, called Octo-Fluo, in combination with anti-FITC adaptor CAR (AdFITC(E2)-CAR) T-cells, may function as an on-off tunable activating bridge between the CAR and SSTR2 expressing target cells. In vitro studies confirmed the binding of Octo-Fluo to Bon1-SSTR2 mCherry-Luc cells without evidence of internalization. AdFITC(E2)-CAR T-cells were activated and efficiently induced Bon1-SSTR2 cell death in vitro, in an Octo-Fluo concentration-dependent manner. Similarly, AdFITC(E2)-CAR T-cells in combination with Octo-Fluo efficiently infiltrated the tumor and eliminated Bon1-SSTR2 tumors in immunodeficient mice in therapeutic settings. Both, AdFITC(E2)-CAR T-cell tumor infiltration and biocidal activity were Octo-Fluo concentration-dependent, with high doses of Octo-Fluo, saturating both the CAR and the SSTR2 antigen independently, leading to the loss of tumor infiltration and biocidal activity due to the loss of bridge formation. Our findings demonstrate the potential of using AdFITC(E2)-CAR T-cells with Octo-Fluo as a versatile, on-off tunable bispecific adaptor for targeted CAR T-cell immunotherapy against SSTR2-positive NETs.

Background & aimsLoss-of-function variants in the PTPN2 gene are associated with increased risk of inflammatory bowel disease. We recently showed that Ptpn2 is critical for intestinal epithelial cell (IEC) barrier maintenance, IEC-macrophage communication, and modulation of the gut microbiome in mice, restricting expansion of a small intestinal pathobiont associated with inflammatory bowel disease. Here, we aimed to identify how Ptpn2 loss affects ileal IEC subtypes and their function in vivo.MethodsConstitutive Ptpn2 wild-type, heterozygous, and knockout (KO) mice, as well as mice with inducible deletion of Ptpn2 in IECs, were used in the study. Investigation was performed using imaging techniques, flow cytometry, enteroid culture, and analysis of gene and protein levels of IEC markers.ResultsPartial transcriptome analysis showed that expression of Paneth cell-associated antimicrobial peptides Lyz1, Pla2g2a, and Defa6 was down-regulated markedly in Ptpn2-KO mice compared with wild-type and heterozygous. In parallel, Paneth cell numbers were reduced, their endoplasmic reticulum architecture was disrupted, and the endoplasmic reticulum stress protein, C/EBP-homologous protein (CHOP), was increased in Ptpn2-KO mice. Despite reduced Paneth cell number, flow cytometry showed increased expression of the Paneth cell-stimulatory cytokines interleukin 22 and interferon γ+ in CD4+ T cells isolated from Ptpn2-KO ileum. Key findings in constitutive Ptpn2-KO mice were confirmed in epithelium-specific Ptpn2ΔIEC mice, which also showed impaired lysozyme protein levels in Paneth cells compared with Ptpn2fl/fl control mice.ConclusionsConstitutive Ptpn2 deficiency affects Paneth cell viability and compromises Paneth cell-specific antimicrobial peptide production. The observed effects may contribute to the increased susceptibility to intestinal infection and dysbiosis in these mice.

Changing where, when, and how objects are studied is central to lab-based science (Knorr Cetina, 1999). Science involves changing the scale of objects--particularly scales of size, time, and intensity--from what is experienced in the world. Similar to investigations conducted in science laboratories, classroom investigations involve re-representing and re-scaling entities, manipulating them, and observing effects in new locations and timescales. However, this aspect of investigation is under-studied and under-utilized as a resource for learning. We argue that, from elementary school, children can experience quantification, or identifying, developing, and working with variables, as consequential and can take up differences in representation and scale in empirical investigations as opportunities for sense-making and conceptual progress. We describe two instantiations of an investigation into heating and cooling, showing that 7- and 8-year-old students oriented to gaps and ambiguities related to temperature and that the redesign supported children and teachers to take up temperature for productive sense-making and conceptual progress. We examine opportunities for quantification across the heating and cooling investigation and a second investigation into landforms. This work has implications for supporting quantification in science activity in the early grades and using empirical investigations as opportunities for sense-making.

Background Anti-PD-1 antibodies have revolutionized cancer immunotherapy due to their ability to induce long-lasting complete remissions in a proportion of patients. Current research efforts are attempting to identify biomarkers and suitable combination partners to predict or further improve the activity of immune checkpoint inhibitors. Antibody-cytokine fusions are a class of pharmaceuticals that showed the potential to boost the anticancer properties of other immunotherapies. Extradomain A-fibronectin (EDA-FN), which is expressed in most solid and hematological tumors but is virtually undetectable in healthy adult tissues, is an attractive target for the delivery of cytokine at the site of the disease.Methods In this work, we describe the generation and characterization of a novel interleukin-7-based fusion protein targeting EDA-FN termed F8(scDb)-IL7. The product consists of the F8 antibody specific to the alternatively spliced EDA of FN in the single-chain diabody (scDb) format fused to human IL-7.Results F8(scDb)-IL7 efficiently stimulates human peripheral blood mononuclear cells in vitro. Moreover, the product significantly increases the expression of T Cell Factor 1 (TCF-1) on CD8+T cells compared with an IL2-fusion protein. TCF-1 has emerged as a pivotal transcription factor that influences the durability and potency of immune responses against tumors. In preclinical cancer models, F8(scDb)-IL7 demonstrates potent single-agent activity and eradicates sarcoma lesions when combined with anti-PD-1.Conclusions Our results provide the rationale to explore the combination of F8(scDb)-IL7 with anti-PD-1 antibodies for the treatment of patients with cancer.

Commensal intestinal bacteria shape our microbiome and have decisive roles in preserving host metabolic and immune homeostasis. They conspicuously impact disease development and progression, including amyloid-beta (Aβ) and alpha (α)-synuclein pathology in neurodegenerative diseases, conveying the importance of the brain–gut–microbiome axis in such conditions. However, little is known about the longitudinal microbiome landscape and its potential clinical implications in other protein misfolding disorders, such as prion disease. We investigated the microbiome architecture throughout prion disease course in mice. Fecal specimens were assessed by 16S ribosomal RNA sequencing. We report a temporal microbiome signature in prion disease and uncovered alterations in Lachnospiraceae, Ruminococcaceae, Desulfovibrionaceae, and Muribaculaceae family members in this disease. Moreover, we determined the enrichment of Bilophila, a microorganism connected to cognitive impairment, long before the clinical manifestation of disease symptoms. Based on temporal microbial abundances, several associated metabolic pathways and resulting metabolites, including short-chain fatty acids, were linked to the disease. We propose that neuroinflammatory processes relate to perturbations of the intestinal microbiome and metabolic state by an interorgan brain–gut crosstalk. Furthermore, we describe biomarkers possibly suitable for early disease diagnostics and anti-prion therapy monitoring. While our study is confined to prion disease, our discoveries might be of equivalent relevance in other proteinopathies and central nervous system pathologies.

Abstract TP53-mutant acute myeloid leukemia (AML) and myelodysplastic neoplasms (MDS) are characterized by chemotherapy resistance and represent an unmet clinical need. Chimeric antigen receptor (CAR) T-cells might be a promising therapeutic option for TP53-mutant AML/MDS. However, the impact of TP53 deficiency in AML cells on the efficacy of CAR T-cells is unknown. We here show that CAR T-cells engaging TP53-deficient leukemia cells exhibit a prolonged interaction time, upregulate exhaustion markers, and are inefficient to control AML cell outgrowth in vitro and in vivo compared to TP53 wild-type cells. Transcriptional profiling revealed that the mevalonate pathway is upregulated in TP53-deficient AML cells under CAR T-cell attack, while CAR T-cells engaging TP53-deficient AML cells downregulate the Wnt pathway. In vitro rational targeting of either of these pathways rescues AML cell sensitivity to CAR T-cell-mediated killing. We thus demonstrate that TP53 deficiency confers resistance to CAR T-cell therapy and identify the mevalonate pathway as a therapeutic vulnerability of TP53-deficient AML cells engaged by CAR T-cells, and the Wnt pathway as a promising CAR T-cell therapy-enhancing approach for TP53-deficient AML/MDS.

Background: Staphylococcus aureus remains a prominent pathogen within health-care environments due to its extensive repertoire of virulence factors. The escalating prevalence of antibiotic-resistant strains has underscored the urgency of identifying alternative treatment strategies. The study focuses on the HtsA siderophore receptor, an integral cell wall component of all S. aureus strains, responsible for iron acquisition from the host environment. Here, we investigate the potential of Bacillus sp. derived macrolides as inhibitors of this critical iron uptake mechanism. Methods: Sixteen distinct macrolide ligands were evaluated for their ability to disrupt iron acquisition by S. aureus through interaction with the HtsA receptor. Employing molecular docking and subsequent molecular dynamics (MDs) simulations, the binding interactions and dynamic behaviors of these ligands with the receptor were assessed. Results: Notably, the complex formed between 7-O-succinyl macrolactin F and HtsA demonstrated a good binding affinity of − 8.5 kcal/mol, outperforming the binding affinity of staphyloferrin A, which exhibited a binding affinity of − 6.9 kcal/mol. MD simulations further corroborated the stability of the 7-O-succinyl macrolactin F-HtsA complex over time, suggesting the potential for this interaction to be harnessed as a novel therapeutic strategy not only for existing antibiotic-resistant strains but also for those that may arise in the future. Conclusion: The findings propose Bacillus species-derived macrolides as potential adjuvant therapies for S. aureus infections, pending comprehensive safety assessments. This research lays the foundation for the development of innovative antimicrobial agents targeting essential virulence-associated mechanisms in S. aureus.

Abstract Chirality is an important topic in biology, chemistry and physics. Here we show that ultrashort circularly polarized laser pulses, which are chiral, can be fired on achiral oriented molecules to induce chirality in their electronic densities, with chirality flips within femtoseconds or even attoseconds. Our results, obtained by quantum dynamics simulations, use the fact that laser pulses can break electronic symmetry while conserving nuclear symmetry. Here two laser pulses generate a superposition of three electronic eigenstates. This breaks all symmetry elements of the electronic density, making it chiral except at the periodic rare events of the chirality flips. As possible applications, we propose the combination of the electronic chirality flips with Chiral Induced Spin Selectivity.