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Vitamin B12 Deficiency in Sickle Cell Disease: Method-Driven Estimates and Systematic Diagnostic Misclassification.

OBJECTIVES: To determine whether the reported 0%-70% prevalence of vitamin B12 deficiency in sickle cell disease (SCD) reflects true population variation or diagnostic misclassification. METHODS: We conducted a PRISMA 2020-compliant systematic review of observational studies (January 1, 2000-May 13, 2026; PROSPERO CRD420251087800) assessing B12 status in SCD. PubMed, AJOL, and Google Scholar were searched with citation tracking and dual screening. Diagnostic validity was assessed across biomarker strategy, analytical platform, thresholds, and confounder control using a proposed context-integrated framework to classify methodological robustness and discordance. RESULTS: Fourteen studies were included (57% high-income; 43% LMIC). The evidence base was dominated by limited diagnostic approaches: 71% used immunoassays, over one-third relied on circulating B12 alone, and functional biomarkers were inconsistently applied without systematic confounder adjustment. Prevalence estimates were strongly influenced by diagnostic methods rather than underlying population biology, ranging from 0% to 70% in single-marker studies (mostly 0%-7.1%, with outliers ~50%-70%) and 6.9%-53% in multi-marker studies. Discordance was substantial and greater in LMIC settings than HIC. CONCLUSION: Current diagnostic approaches in SCD appear method-dependent, generating heterogeneous prevalence estimates with uncertain clinical validity. These findings challenge existing estimates and have implications for clinical practice, research design, and diagnostic equity. TRIAL REGISTRATION: ClinicalTrials.gov identifier: CRD420251087800.

Humans

Coordinated use of three homocysteine methyltransferases supports l-methionine biosynthesis and environmental adaptation among plant-associated bacteria.

Plant pathogens colonize multiple plant-associated habitats throughout their life cycle, encountering distinct nutrient conditions and microbial communities. l-methionine is required for bacterial growth and environmental adaptation. However, how plant pathogens coordinate l-methionine biosynthetic pathways to adapt to different plant-associated environments remains poorly understood. Here, using the plant pathogen Xanthomonas campestris pv. campestris strain XC1 as a model, we show that three homocysteine methyltransferase pathways allow XC1 to catalyze the final step of l-methionine biosynthesis using different methyl donors and cofactors under different environmental conditions. Bioinformatic and transcriptional analyses identified three homocysteine methyltransferase-associated operons in XC1, mesMXD, mmuPM, and metHRHaHb, corresponding to the MesD-, MmuM-, and MetHaHb-dependent pathways, respectively. MesD uses an endogenously synthesized methyl donor and functions as the dominant homocysteine methyltransferase under l-methionine-limiting conditions, supporting bacterial growth, intracellular l-methionine accumulation, and full virulence. Furthermore, MmuM enables XC1 to use plant-derived S-methylmethionine for l-methionine biosynthesis, whereas MetHaHb enables XC1 to use vitamin B12 supplied by a neighboring bacterium for l-methionine biosynthesis in co-culture. Expression analyses showed that mesMXD was the only homocysteine methyltransferase-associated operon that responded to l-methionine availability, and its expression also decreased when S-methylmethionine- or vitamin B12-dependent pathways supported l-methionine biosynthesis. Comparative genomic analysis further showed that the three-homocysteine methyltransferase configuration is conserved in Xanthomonas and is also present in other plant-associated bacteria. Together, these findings show that a plant pathogen can coordinate endogenous, plant-derived, and microbially supported homocysteine methyltransferase pathways to maintain l-methionine biosynthesis, providing a metabolic strategy for adaptation to plant-associated environments.

Methionine

Metformin Adherence and Risk of Polyneuropathy in Type 2 Diabetes Mellitus: An International Matched Cohort Study with Independent Validation.

BACKGROUND: Metformin is a popular first-line glucose-lowering medication for type 2 diabetes mellitus (T2DM). Although metformin reduces the risks of various complications of diabetes, its potential to cause polyneuropathy by depleting vitamin B12 levels is concerning. This study investigated whether the adherence or discontinuation of metformin after adding-on a second-line antiglycemic agent increases the risk of polyneuropathy in patients with T2DM. METHODS: Data from TriNetX were obtained, and patients with T2DM who were receiving second-line antiglycemic agents were divided into metformin-adherent and metformin-nonadherent groups based on prescription claims data. Neuropathy incidence was evaluated using diagnostic claims and nerve conduction examinations. For independent confirmation and external validation of the primary findings, we used data from the National Health Insurance Research Database (NHIRD) of Taiwan. RESULTS: After matching, 58,027 patients were included in each group. Compared with metformin adherent patients, metformin nonadherent patients had a higher risk of polyneuropathy (adjusted hazard ratios [aHR] 1.26; 95% confidence interval [CI] 1.23-1.29; P < 0.001). Risks of diabetic foot ulcer, amputation, neuropathy-related medication use, and bone fracture were also higher among nonadherent patients. Sensitivity analyses confirmed the robustness of findings. In the validation NHIRD cohort (31,384 matched pairs), metformin nonadherence remained associated with increased polyneuropathy risk (aHR 1.25; 95% CI 1.10-1.42; P < 0.001). CONCLUSIONS: Metformin adherence in patients with T2DM who require second-line treatment may reduce the risk of polyneuropathy; vitamin B supplementation may enhance this benefit.

Humans

Vegan multinutrient supplementation significantly increases Omega-3 index and 25-OH-vitamin D status: a randomized, double-blind, placebo-controlled trial in healthy young vegans.

In this randomized, double-blind, placebo-controlled trial, 72 healthy vegan adults (aged 19-57 years) received a multinutrient supplement consisting of a vitamin and mineral supplement (providing 26 &#xb5;g vitamin D) and an omega-3 supplement administered in either a single dose (EPA 98.7 mg, DHA 171.0 mg, additional vitamin D 36 &#xb5;g, vitamin E 3.7 mg) or a double dose (EPA 197.4 mg, DHA 342.0 mg, additional vitamin D 72 &#xb5;g, vitamin E 7.4 mg) or placebo capsules for 4 months. Nutrient biomarkers were assessed at baseline and at the end of the intervention after 4 months. An analysis of covariance was employed to test for between-group differences (p < 0.05) and adjusted for multiple testing using the Bonferroni-Holm method. Compared to the control group, which showed on average a significant decline in both the omega-3-index and 25-hydroxyvitamin D, participants in both intervention groups demonstrated significant increase in these parameters (p < 0.001). Although the double dose group exhibited numerically greater increases in omega-3 index and vitamin D compared to the simple dose group, the differences between these dosing regimens were not statistically significant. As expected, vitamin E levels remained unchanged, reflecting its inclusion solely for antioxidative protection in the omega-3 supplement rather than as a critical nutrient in vegan diets. In conclusion, supplementation significantly improved omega-3 and vitamin D status in healthy vegans, with no significant benefit from doubling the dose. Although clinical endpoints were not evaluated, improved nutrient status may have potential implications for health. The study has been registered at the German Clinical Trials Register (DRKS00028151).

Humans

Xerophthalmia and ocular manifestations of vitamin A deficiency in children in high-income countries: A systematic review.

Xerophthalmia is a vision-threatening eye condition caused by vitamin A deficiency (VAD). Cases of xerophthalmia in high-income countries (HICs) are vulnerable to misdiagnosis, causing delays in treatment and adverse visual outcomes. We define the features, causes and complications of VAD and xerophthalmia in children of HICs. Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines (CRD42024492023). We performed a search for eligible articles on Scopus, Web of Science, Cochrane, PubMed and Medline. Cases reporting on children under 18 years of age residing in HICs with ocular features of VAD were eligible for inclusion. The search yielded 2474 results; 43 case reports and case series met the inclusion criteria consisting of a total of 61 cases (mean age 9.9&#x202f;&#xb1;&#x202f;4.2 years, range 3-17 years). Xerophthalmia was graded according to the most advanced finding for each case: 21.3% had night blindness only; 29.5% had conjunctival xerosis or Bitot spots; 29.5% had corneal xerosis, ulceration or scarring; 1.6% had xerophthalmia fundus only; and 18.0% had ocular manifestations associated with VAD that are not encompassed under the WHO classification. These features included swollen optic discs, optic neuropathy, or ocular dryness. Restrictive dietary practises were the most common mechanism of deficiency (75%), and autism was the most common underlying condition (49%). This shows that VAD remains a cause of severe visual impairment in HICs, especially when associated with delays in diagnosis and treatment. Further research is required to establish the prevalence of xerophthalmia in HICs.

Humans

Multiplexed CRISPR/Cas9 mediated knockdown of BCH gene in potato enhances beta-carotene to combat vitamin A deficiency.

The inadequate amounts of provitamin A carotenoids in crops contribute to the widespread vitamin A deficiency, leading to malnutrition and blindness in humans. Suppression of the &#x3b2;-carotene hydroxylase (BCH) increases &#x3b2;-carotene levels. In the current study, we utilized the multiplexed CRISPR/Cas9 approach by designing three targets against the BCH gene in a local potato cultivar. Transformation efficiency was recorded as 15%, the successful integration of the CRISPR/Cas9-BCH multiplex construct in potatoes was confirmed through PCR. When analysed using TIDE software, Sanger sequencing revealed the highest indel efficacy of 92.1% in plant 7 and 26.6% in plant 1. qRT-PCR (quantitative real-time PCR) analysis indicated a significant 89-fold reduction in BCH transcript levels in genome-edited potato lines compared to control plants. Spectrophotometry demonstrated a notable increase in beta-carotene levels in genome-edited potato plants, ranging from 0.831&#x202f;&#xb5;g/mL FW to 4.236&#x202f;&#xb5;g/mL FW, compared to the control plant with the lowest beta-carotene concentration (0.344&#x202f;&#xb5;g/mL FW). HPLC analysis further confirmed increased beta-carotene levels in genome-edited potato plants, ranging from 0.11&#x202f;mg/mL FW to 0.36&#x202f;mg/mL FW, compared to the unmodified control plant with a minimum beta-carotene value of 0.09&#x202f;mg/mL. Our results revealed that the multiplexed CRISPR-Cas9 approach targeting the BCH gene results in enhanced beta-carotene contents in potato tubers.

Solanum tuberosum

High-Dose Intravenous Vitamin C and Mortality and Organ Dysfunction in Severe Burn Injury: The VICTORY Randomized Clinical Trial.

IMPORTANCE: Severe burn injury triggers systemic inflammation that can lead to multiple organ dysfunctions and death. High-dose intravenous vitamin C has been proposed to mitigate these effects, but strong evidence in patients with burn injury is lacking. OBJECTIVE: To evaluate the efficacy of high-dose intravenous vitamin C in patients with severe burn injury. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind, placebo-controlled phase 3 trial conducted across 24 burn centers in North, Central, and South America; Europe; and Asia. Adults (&#x2265;18 years) with deep second- and/or third-degree burns covering 20% or more of total body surface area and requiring skin grafting were enrolled between August 18, 2020, and September 12, 2025. Final follow-up was completed in March 2026. The trial was stopped early after the first prespecified interim analysis for futility/harm. INTERVENTIONS: Patients were randomly assigned (1:1) to receive intravenous vitamin C (50 mg/kg every 6 hours for 96 hours) or matched placebo. MAIN OUTCOMES AND MEASURES: The primary outcome was a composite of 28-day mortality and persistent organ dysfunction (defined as dependence on mechanical ventilation, kidney replacement therapy, or vasopressor/inotrope support at day 28). The main secondary outcome was time to discharge alive from hospital within 90 days. RESULTS: Among 238 patients enrolled (mean age, 48.9 [SD, 19.1] years; 79% male; mean total body surface area, 37.0% [SD, 14.6%]), 120 were assigned to vitamin C and 118 to placebo. The primary composite outcome occurred in 49 patients (40.8%) in the vitamin C group and 35 patients (29.7%) in the placebo group (adjusted risk ratio [RR], 1.28 [95% CI, 0.99-1.65]; P&#x2009;=&#x2009;.06), crossing the prespecified futility/harm threshold and prompting early trial termination. Time to discharge alive from hospital within 90 days was not improved (adjusted subdistribution hazard ratio, 0.85 [95% CI, 0.62-1.16]; P&#x2009;=&#x2009;.31). Twenty-eight-day mortality was higher in the vitamin C group (15.0% vs 7.6%; adjusted RR, 1.96 [95% CI, 1.32-2.90]; P&#x2009;=&#x2009;.001), as was hospital mortality (23.3% vs 16.1%; adjusted RR, 1.44 [95% CI, 1.03-2.00]; P&#x2009;=&#x2009;.03). CONCLUSIONS AND RELEVANCE: Among patients with severe burn injury, high-dose intravenous vitamin C did not reduce 28-day mortality and persistent organ dysfunction and is possibly harmful. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04138394.

Humans

The association of 25-hydroxyvitamin D deficiency with neuroinflammation and prognosis in HIV-negative cryptococcal meningitis.

BACKGROUND: Cryptococcal meningitis (CM) in HIV-negative individuals is increasing, yet the role of vitamin D remains unclear. This study investigates serum 25-hydroxyvitamin D [25(OH)D] levels and their clinical implications in HIV-negative CM patients. METHODS: We conducted a retrospective case-control study of 93 HIV-negative CM patients and 191 healthy controls (HCs). Serum 25(OH)D levels, cerebrospinal fluid (CSF) fungal burden, cytokine profiles, the incidence of postinfectious inflammatory response syndrome (PIIRS), and one-year mortality were assessed. Bivariate logistic regression models identified predictors of mortality. RESULTS: CM patients had significantly lower serum 25(OH)D levels than HCs (18.33 vs. 23.69&#xa0;ng/mL, p&#xa0;<&#xa0;0.001), with a higher rate of deficiency (<20&#xa0;ng/mL) in the CM group (59.14% vs. 34.03%, p&#xa0;<&#xa0;0.001). Lower 25(OH)D levels were associated with elevated CSF levels of IL-6 and IL-8 (p&#xa0;<&#xa0;0.05). Deficiency was linked to increased PIIRS incidence (43.64% vs. 21.05%, p&#xa0;=&#xa0;0.028). Bivariate logistic regression showed a protective trend for 25(OH)D levels (OR 0.939, 95% CI 0.877-1.006, p&#xa0;=&#xa0;0.075), although deficiency was not associated with higher mortality. CONCLUSIONS: Serum 25(OH)D deficiency is prevalent in HIV-negative CM patients and linked to neuroinflammation and increased risk of PIIRS. Serum 25(OH)D levels may serve as a useful prognostic marker, although further research is needed.

Humans

Seventeen-year follow-up of hypophosphatasia diagnosed in middle-aged siblings harboring a novel intronic and a rare missense ALPL gene mutation.

Hypophosphatasia (HPP) is the rare inborn-error-of-metabolism that features impaired mineralization of the skeleton and teeth due to a deactivating mutation or mutations of the gene ALPL which encodes the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). We report 17-year follow-up of twin sisters and a brother referred in middle-age for painful proximal femoral "stress fractures" and then diagnosed with HPP. They reported generalized muscle and bone pain, metatarsal fractures, arthropathy and, since childhood, tooth loss. Their concordant findings were explained by compound heterozygosity in ALPL for a rare maternal missense mutation (c.1403C&#xa0;>&#xa0;T, p.Ala468Val) in exon 12, together with a novel presumably paternal change (c.863-14G&#xa0;>&#xa0;A) predicting a cryptic mRNA splice site in intron 8. Fractures continued during follow-up until one sister received a three-and-one-half-year course of hydroxyapatite-targeted TNSALP supplementation therapy (asfotase alfa) during which substantial improvement occurred in her clinical, biochemical, and functional parameters as well as quality of life. Following subsequent unplanned treatment cessation she suffered significant clinical deterioration, including new fractures and loss of mobility. Her bone histopathology documented osteomalacia. Treatment resumption restored its benefits. Among ten asymptomatic family members evaluated in this four-generation kindred, eight were carriers heterozygous for either ALPL mutation. Those harboring the maternal missense defect manifested mild hypophosphatasemia, suggesting a dominant-negative mutation effect. This experience underscores the importance of in-depth phenotyping and then clinical follow-up to characterize ALPL variant combinations, and for maintaining effective asfotase alfa treatment.

Humans

Retinoid dynamics in immune cells during age-related diseases.

Retinoids comprise vitamin A and its structurally related natural and synthetic derivatives. Retinoid dynamics involves multiple retinoid forms, carrier proteins, and enzymes that orchestrate the absorption, transport, storage and biotransformation of dietary vitamin A. Beyond their canonical metabolic functions, metabolites and proteins involved in retinoid metabolism also play distinct roles in signal transduction and transcriptome reprogramming, broadening the mechanisms that influence immune cell fate decisions. Age&#x2011;related changes in retinoid bioavailability and signaling intensity alter immune cell polarization and function, thereby contributing to the pathogenesis of chronic inflammation in neurodegenerative diseases, cardiovascular diseases, osteoarthritis, and other age-related diseases. In this review, we focus on age-related alterations in the retinoid metabolic pathway and their impact on inflammation and the progression of age-related diseases. This review highlights the pivotal role of retinoid metabolism in anti-ageing interventions and considers future directions and challenges in this field.

Humans

A smartphone-integrated Pt@Cu-HCF nanozyme-based paper sensor for on-site determination of total antioxidant capacity in marine oils.

Total antioxidant capacity (TAC) serves as a key indicator for evaluating the nutritional quality of foods. In this study, we designed a platinum-embedded copper hexacyanoferrate (denoted as Pt@Cu-HCF) nanozyme that exhibits high oxidase-like activity, efficiently catalyzing the oxidation of chromogenic substrates to generate robust colorimetric signals. Antioxidants quench hydroxyl radicals (&#x2219;OH) produced during the catalytic process, leading to a concentration-dependent suppression of the color signal. Leveraging this mechanism, a smartphone-integrated, colorimetric paper sensor for on-site TAC quantification was developed, using vitamin E as the calibration standard. The sensor was applied to determine TAC in fish oil, algal oil, and krill oil, demonstrating a linear response range of 9.78-312.5&#xa0;&#x3bc;M and a limit of detection (LOD) of 6.41&#xa0;&#x3bc;M. Validation using real-world marine oil samples showed excellent agreement with a commercial assay kit, confirming the reliability and practical applicability of this portable sensor for TAC measurement in complex biological matrices.

Antioxidants

Uncovering parental exposure risks of TCPP: Impaired development and metabolic homeostasis in zebrafish offspring.

As brominated flame retardants are phased out, tris (1&#x2011;chloro-2-propyl) phosphate (TCPP), a phosphorus-based flame retardant, has emerged as a prominent detectable flame retardant in the environment. However, TCPP has been found to exhibit endocrine-disrupting effects on organisms, raising significant safety concerns. In our study, we utilized the zebrafish model to explore the toxic effects of parental TCPP exposure on offspring and uncover its regulatory mechanisms through metabolomics analysis. Moreover, the impact on the nervous system and lipid metabolism was examined through behavioral analysis and specific staining. Our findings demonstrated that both embryonic and parental TCPP exposure induced developmental disorders in larvae, along with decreased locomotor activity and disordered lipid metabolism homeostasis. Parental exposure to TCPP, exhibiting stronger developmental toxicity than direct embryonic exposure, notably led to reductions in crucial energy substrates such as amino acids and carbohydrates. Meanwhile, embryonic TCPP exposure primarily affected the endogenous lipid-related metabolites including phospholipids, lipid-soluble vitamins, steroids and fatty acids, promoting lipid accumulation in larval liver and subcutaneous tissue. What's more, continuously parental and embryonic exposure showed the most pronounced effects on zebrafish development and metabolic regulation. Our study highlights the risk posed by parental exposure to TCPP on offspring zebrafish, underscoring the need for comprehensive consideration of the impact from parental exposure in pollutants regulation.

Animals

Early infantile developmental and epileptic encephalopathy: clinical spectrum, diagnosis, outcomes, and evolving treatment strategies.

Early infantile developmental and epileptic encephalopathy (EIDEE) is among the most severe epilepsy syndromes, with onset before three months of age and an estimated incidence of approximately 10 per 100,000 live births. The 2022 International League Against Epilepsy classification unified the historically distinct Ohtahara syndrome and early myoclonic encephalopathy under a single diagnostic framework defined by frequent drug-resistant tonic and/or myoclonic seizures, an abnormal neurological examination, and an abnormal interictal electroencephalogram-most characteristically a burst-suppression pattern. This narrative review synthesizes the clinical, electrophysiological, neuroimaging, genetic, and therapeutic literature within the EIDEE framework. The clinical phenotype is characterized by central hypotonia, postnatal microcephaly, cortical visual impairment, and age-dependent syndromic evolution toward infantile epileptic spasms syndrome or Lennox-Gastaut syndrome in the majority of patients. Electroencephalography remains essential for syndromic classification, while systematic metabolic screening and early trio whole-exome or whole-genome sequencing are central to the etiologic workup, achieving diagnostic yields of 60-65%. The most commonly identified genetic causes include STXBP1, KCNQ2, and SCN2A variants. Outcomes are poor overall and strongly etiology-dependent: vitamin-responsive disorders carry a substantially more favorable prognosis, whereas mortality reaches 25% in genetic cohorts. Genotype-guided pharmacotherapy is now applicable to a clinically meaningful subset of patients, with sodium channel blockers, potassium channel openers, and emerging antisense oligonucleotide therapies representing important therapeutic advances. Gene therapy trials are underway but have encountered early safety signals, underscoring the vulnerability of this population. Critical unmet needs include earlier molecular diagnosis, precision therapies targeting developmental outcomes beyond seizure control, and prospective international registries to characterize the long-term natural history of EIDEE.

Humans

Generation of spCAS9 expressing human mesenchymal stem cell line to study gene function during osteoblast differentiation.

Human bone marrow-derived stromal cells (hMSCs) are a great resource for studying how genes influence cell fate and differentiation into various cell types like osteoblasts, adipocytes, and chondrocytes, among other cell types. However, genetic manipulation of primary hMSCs has been challenging due to their short lifespan and cellular senescence after limited passaging. Their low and unstable transfection efficiency also complicates gene delivery or inactivation, hindering long-term functional studies. The limited lifespan has been effectively solved by immortalizing hMSCs with telomerase reverse transcriptase (hMSCs-TERT). The use of these cells is ideal for functional studies of osteoblast and adipocyte differentiation through genetic manipulation, providing a stable and reliable model. Here, we have engineered a stable CAS9 expressing hMSC-TERT cell line (hMSC-TERTCAS9) via lentiviral transduction. The constitutive expression of spCas9 enables efficient and reproducible gene editing. We demonstrate the potential of these hMSC-TERTCAS9 cells for generating gene disruptions using plasmid delivery of guide RNAs as a fast and efficient strategy for targeted genome editing. The edited cells can be sorted and expanded as single cells to obtain homogenous clonal cell lines with mono- as well as bi-allelic gene deletions, a crucial step for producing reliable experimental results. We further validate this cell line as a powerful tool for studying gene function during hMSC proliferation and differentiation, providing 3 distinct examples of its utility. Through the generation of indels, single-cell sorting, and clonal selection, we have efficiently inactivated the vitamin D receptor and created both larger (256 nucleotides) gene disruptions in Forkhead box protein O1 and precise removals of a small genomic sequence (73 nucleotides) coding for microRNA MIR675. This novel hMSC-TERTCAS9 cell line represents a significant advancement, offering a stable, efficient, and versatile platform for advanced genetic studies, high-throughput screening, and the creation of reliable cellular disease models.

CRISPR-Cas9

The Childhood Cancer and Leukemia International Consortium (CLIC): Expanding global collaboration in pediatric cancer etiology research.

Childhood cancers are rare, but incidence has risen modestly in countries with robust registration, partly reflecting improved diagnosis. In high-income countries, cancer is the leading cause of disease-related death in children. Marked inequities in incidence, survival, and research capacity underscore the need for large-scale collaboration to identify environmental, genetic, and contextual determinants of risk. The Childhood Cancer and Leukemia International Consortium (CLIC) was established in 2007 to study the etiology of childhood leukemia and later expanded in 2019 to include other childhood cancers, principally solid tumors. CLIC pools harmonized, individual-level data from case-control and cohort studies, obtained through interviews, record linkage (insurance claims, registries), or geographic information systems, and integrates germline genomic data where available. Membership has grown from 13 studies in 9 countries to 57 studies in 21 countries; recruitment spans the early 1960s to the present and encompasses approximately 150,000 cases across all tumor types and 300,000 controls with clinical, demographic, and exposure data, centralized via harmonized data dictionaries at the Data Coordination Center, established in 2014 at the International Agency for Research on Cancer, and supported by a secure analysis platform. Pooled analyses across diverse populations have implicated parental age, prenatal vitamin or folic acid use, mode of delivery, fetal growth, selected congenital anomalies, occupational or household exposures (e.g., pesticides), paternal smoking, and markers of early-life immune modulation (e.g., breastfeeding, daycare attendance) in leukemia risk, informing carcinogen evaluation and prevention. The integration of genetic ancestry and germline susceptibility data is clarifying ancestry-related differences in leukemia biology and outcomes, while confirming risk loci with population-specific effects. CLIC is now adding polygenic risk scores and exposomic data to refine etiologic subtyping and identify modifiable pathways, while broadening representation from underserved regions through partnership-building and capacity-strengthening.

Humans

Proteome-level evidence that tebuconazole, both alone and in interaction with thiacloprid, affects epigenetic events in bumblebee heads.

Tebuconazole, a widely used ergosterol biosynthesis-inhibiting fungicide, can affect nontargets, especially when combined with insecticides. We employed label-free quantitative proteomics to investigate the effects of long-term exposure to sublethal concentrations (100&#xa0;&#x3bc;g/L) of tebuconazole, either by itself or alongside the neonicotinoid thiacloprid (100&#xa0;&#x3bc;g/L), on the heads of Bombus terrestris workers. A Bayesian factor power analysis revealed that the experiment produced conclusive proteomic results. Tebuconazole treatment revealed eleven differentially abundant proteins, which increased elevenfold with thiacloprid. The proteins that changed in the same direction in both treatments suggest the occurrence of epigenetic events because they are involved in histone trimethylation (H3K4me3), pre-mRNA processing, and folate (vitamin B9) metabolism. Following co-exposure, the abundance of histone H2A.V and its associated proteins was affected. Two important detoxification-related proteins, CYP6BE1 and CYP6AQ1 (honey bee homologs), were identified, as well as proteins that suggest hormonal and neurotoxic effects. Overall, this study suggests that tebuconazole affects key epigenetic processes in bumblebee heads at the proteome level, though this was not confirmed at the biological level or through orthogonal methods. The tested chemicals were previously found to affect trimethylations, but not H3K4me3. We suggest analyzing the different trimethylations, their interplay, and associated hallmarks, such as folate levels. SIGNIFICANCE: The effects of pesticides and their combinations on organisms can be unexpected until they are examined using modern, complex methods. High-throughput proteomics can provide data on important biochemical processes affected by pesticides, offering a different perspective to that at the expression level. Despite their low acute toxicity, a group of fungicides that inhibit (ergo)sterol biosynthesis (EBI or SBI) are considered dangerous to pollinators, including bumblebees. This is due to the increasing toxicity of insecticides through the inhibition of cytochrome P450 detoxification enzymes. We found that tebuconazole had a similar effect on epigenetic events when used alone or in combination with the insecticide thiacloprid. Key proteins suggest that H3K4 histone trimethylation (H3K4me3) was impacted. To our knowledge, this expands the existing evidence suggesting that tebuconazole/triazole fungicides affect histone trimethylation H3K27me3. Since literature shows that thiacloprid affects H3K9me3, it is possible that thiacloprid and tebuconazole interact in these epigenetic events that affect each other. Overall, our results suggest that tebuconazole affects proteins involved in histone trimethylation, pre-mRNA processing, and folate metabolism. These are all hallmarks of epigenetic processes and were further extended by the co-exposure of tebuconazole and thiacloprid to more differently abundant proteins. Additionally, the results provide data on cytochrome P450s of the CYP6 family, which act as detoxifying proteins, as well as proteins that indicate hormonal and neurotoxic effects in bumblebee heads. Finally, the results of the Bayesian power analysis confirmed the meaningfulness of the proteomic data analyzed in this study. If the new findings obtained at the proteome level are verified by different methods, the full extent of the side effects of tebuconazole can be revealed.

Animals