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Comparison of black carbon measurements using filter-specific reference transmittance to those using lab blanks or an average of unloaded filters.

Filter-based optical techniques compare light transmission intensities between loaded (I) and unloaded (I0) filters as a measure of light-absorbing mass for subsequent estimations of equivalent black carbon (eBC). We analyzed 5,379 15 mm Teflon filters from the Household Air Pollution Intervention Network (HAPIN) trial to assess the influence that different methods of I0 estimations have on eBC measures. We compared eBC measurements using filter-specific I0 values (Method 1) to those using three other methods of I0 estimation: the lab blank scan from a given session (Method 2), the average of all pre-sample filter scans (Method 3), and the average of all lab blank filter scans (Method 4). We assessed the agreement between Method 1 and the alternative methods using Bland-Altman analysis. We also assessed the relationship between Method 1 and the alternative methods across the complete measurement range and after stratifying exposure data into quartiles according to Method 1 eBC exposures. The mean (SD) personal eBC exposure for Method 1 was 7.8 μg/m3 (5.9), and exposures ranged from 1.3 to 46.8 μg/m3. Compared to Method 1, eBC using Methods 2, 3, and 4 were higher by 0.7 μg/m3, 0.1 μg/m3, and 0.7 μg/m3, respectively. The performances of linear regression models between Method 1 and all other methods were moderate to strong (R2 range: 0.42-0.93) in the second, third, and fourth quartiles; however, the models in the first quartile (eBC range: 1.3-2.9 μg/m3) performed poorly (R2 = 0.25-0.26), with error approximately 25% of the mean. Our findings suggest that, in most instances, conventional methods for obtaining I0 values can be used to sufficiently characterize eBC; however, analyzing filters before sampling adds appreciably to the accuracy of eBC estimations in lower concentration settings.Implications: Filter-based optical techniques compare light transmission intensities between loaded (I) and unloaded (I0) filters as a measure of light-absorbing mass for subsequent estimations of equivalent black carbon (eBC). To assess the influence that different methods of I0 estimations have on eBC measures, we analyzed 5,379 15 mm Teflon filters from the Household Air Pollution Intervention Network (HAPIN) trial. Our findings suggest that, in most instances, conventional methods for obtaining I0 values can be used to sufficiently characterize eBC; however, analyzing filters before sampling adds appreciably to the accuracy of eBC estimations in lower concentration settings.

Soot

Maternal disease control and pregnancy outcomes with anti-CD20 therapy versus natalizumab in multiple sclerosis: a systematic review.

BACKGROUND: Management of multiple sclerosis (MS) during pregnancy requires balancing maternal disease control with fetal safety. Among high-efficacy disease-modifying therapies, anti-CD20 monoclonal antibodies and natalizumab are commonly used in women with active disease, yet their comparative effectiveness and safety during pregnancy remain incompletely defined. This systematic review evaluated maternal disease activity and pregnancy-related outcomes associated with anti-CD20 exposure compared with natalizumab in pregnant women with MS. METHODS: PubMed/MEDLINE, Web of Science, Scopus, and the Cochrane Library were searched from inception through February 2026. Eligible studies included pregnant women with MS exposed to anti-CD20 before or during pregnancy and reporting maternal disease activity compared to natalizumab. RESULTS: Seven studies were included, comprising six observational cohort studies and one pharmacovigilance disproportionality analysis. Across studies, anti-CD20 exposure was consistently associated with lower relapse activity than natalizumab, particularly in the postpartum period. Anti-CD20 strategies were also associated with markedly lower postpartum MRI activity and more favorable disability-related outcomes where reported. Meta-analysis of three studies demonstrated a significant reduction in postpartum MRI activity with anti-CD20 therapy compared with natalizumab (RR 0.06, 95% CI 0.02-0.24; I² = 0%). No clear increase in major congenital anomalies was identified, although some data suggested higher odds of small for gestational age and maternal antibiotic use with anti-CD20 exposure. CONCLUSIONS: Anti-CD20 therapy was associated with lower maternal disease activity than natalizumab during pregnancy, especially for relapse prevention and postpartum MRI suppression. However, evidence regarding fetal and neonatal safety remains limited, warranting cautious individualized treatment decisions and further comparative research.

Humans

Micro- and nanoplastics-induced neurotoxicity: a CNS-centered, evidence-graded adverse outcome pathway framework based on systematic weight-of-evidence assessment.

Micro- and nanoplastics (MPs/NPs) are ubiquitous anthropogenic particulate pollutants posing emerging threats to human neurological health. Severe heterogeneity in particle physicochemical properties, environmental aging status, exposure paradigms and experimental platforms has created persistent mechanistic uncertainties in MP/NP neurotoxicology, hindering reliable hazard characterization and risk translation. Here, we systematically consolidate empirical toxicological evidence and construct a dedicated central nervous system (CNS)-targeted adverse outcome pathway (AOP) network integrated with rigorous weight-of-evidence (WoE) grading to elucidate the hierarchical, particle-specific toxic cascades underlying MP/NP-induced neural injury. Our synthesis overturns the conventional linear toxicity paradigm, demonstrating that MPs/NPs trigger neurotoxicity via a complex multi-input mechanistic network. We definitively establish oxidative stress as a robust early convergent key event-rather than a universal molecular initiating event-orchestrating ROS overproduction, lipid peroxidation, mitochondrial dysfunction, and neuroinflammation to propagate neuronal damage. This core module is driven by five distinct particulate upstream triggers: particle-biomolecule interfacial perturbation, corona-facilitated cellular internalization, plastic-associated chemical leaching, aging-derived free radical reactivity, and gut-borne systemic neurotoxic signaling. Downstream pathogenic outcomes encompass glial overactivation, neurotransmitter dyshomeostasis, autophagy-lysosome dysfunction, metabolic reprogramming, regulated neuronal cell death, and behavioral impairments. Tiered WoE analysis confirms strong validation for early oxidative/inflammatory cascades, moderate support for gut-brain axis crosstalk and intracellular trafficking disruption, and nascent evidence for synaptic dysfunction and neurodegeneration-linked proteostatic defects. Extrapolation to human health risk remains constrained by the frequent use of high-dose exposure paradigms, limited validated data on internal dosimetry in the human brain, discrepancies between effective concentrations in experimental models and environmentally relevant human tissue burdens, and insufficient causal validation of distal adverse outcomes. We highlight key research priorities including aged mixed-particle exposure systems, leachate-controlled assays, quantitative internal dose evaluation, and mechanistic intervention verification. This evidence-stratified AOP framework resolves longstanding mechanistic ambiguities in particulate neurotoxicity, providing a standardized, causality-based foundation for future mechanistic exploration and health risk assessment of global plastic pollution.

Adverse outcome pathway

Comprehensive study on pesticide residues and mycotoxins in freeze-dried strawberries and raspberries.

Freeze-dried fruit has gained popularity because it preserves the flavour and nutritional value of fresh fruit while providing extended shelf life. Despite this, there are concerns regarding its chemical safety. This study evaluated 58 freeze-dried fruit products from the Czech retail market, focusing on potential contamination. Pesticide residues and mycotoxins were determined using LC-MS/MS and GC-MS/MS. Overall, 111 pesticide residues (or their metabolites) and 3 mycotoxins were quantified. After applying processing factors, 12 pesticide residues exceeded EU maximum residue limits. Prohibited substances, including carbofuran, omethoate, and haloxyfop, were detected. Tenuazonic acid was found in 71% of samples, while alternariol and tentoxin were detected less frequently. More than half (54%) of strawberry samples contained 10 or more pesticide residues, indicating potential cumulative exposure concerns, particularly for children with lower body weight. These findings highlight the need for continued monitoring of freeze-dried fruits and further assessment of dietary exposure.

Pesticide Residues

Oil and gas well development and coccidioidomycosis risk in Kern County, CA, USA: a case-crossover study.

BACKGROUND: Coccidioidomycosis is an emerging fungal disease caused by inhaling Coccidioides spp spores. As spores reside in soil, activities that disturb soil and generate dust can aerosolise and transport the pathogen. The oil and gas industry has been extensively developed in some regions that are endemic for Coccidioides spp and has been associated with dust emissions. Although several adverse health outcomes have previously been associated with oil and gas development, its impact on coccidioidomycosis risk has not been investigated. We aimed to estimate the association between exposure to oil and gas well development (ie, wells in preproduction) and risk of coccidioidomycosis among residents living near new wells. METHODS: In this case-crossover study, we obtained information on reported coccidioidomycosis cases and oil and gas well development between 2007 and 2022 in Kern County, CA, USA. We then compared exposure to preproduction wells within 5 km of each individual's place of residence during both hazard (ie, the 49-139 days before case onset) and control periods using conditional logistic regression. FINDINGS: During the study period, 658 108 (72·4%) of 909 282 of Kern County residents lived within 5 km of at least one preproduction well, and 116 020 (12·8%) lived within 5 km of 23 or more preproduction wells within a single 90-day period. We estimated that the odds of coccidiomycosis incidence were 12·5% (95% CI 5·8-19·6) higher in the 90 days following exposure to at least one preproduction well within 5 km of an individual's place of residence and that the odds of infection increased by 0·7% (0·4-0·9) for each additional preproduction well developed within this distance. INTERPRETATION: These findings support a previously-unrecognised association between the development of oil and gas wells and transmission of coccidioidomycosis, potentially driven by dust generation. Given the prevalence of oil and gas development in the study region, its impact on coccidioidomycosis incidence might be large. FUNDING: National Institutes of Health, National Science Foundation.

Journal Article

Does high fructose consumption trigger microglia activation and neuroinflammation? A systematic review.

This systematic review evaluated the effects of fructose intake on neuroinflammatory markers in rodent models. The search terms Fructose AND neuroinflammation OR Neurodegeneration OR chemokines OR interleukins OR microglia OR behaviour OR memory OR cognition were used in Google Scholar, Scopus and Web of Science. Thirteen animal studies investigating fructose-induced neuroinflammation that matched the eligibility criteria were included in the study. Across the studies, 16 inflammatory markers were identified and significantly altered following exposure to fructose. The findings consistently demonstrated elevated expression of pro-inflammatory cytokines, TNF-α, IL-6, and IL-1β, following fructose administration. Fructose consumption also dysregulated MCP-1, fractalkine, and CX3CR1 levels, thereby promoting inflammatory signalling and microglial activation. Furthermore, fructose exposure significantly increased IBA-1 and CD11b, indicating sustained neuroimmune activation. Alterations in important inflammatory pathways involving TLR4, NLRP3, NF-κB, MyD88, iNOS, and cyclooxygenases (COX-1 and COX-2) were also observed. In contrast, expression of the anti-inflammatory regulator peroxisome proliferator-activated receptor gamma (PPARγ) was reduced after fructose treatment. Overall, the findings suggest that chronic fructose consumption induces neuroinflammation through multiple inflammatory and immune-related mechanisms in the brain. These effects appear to be dose- and duration-dependent and may contribute significantly to neurodegeneration and cognitive impairment.

Microglia

The spatial and temporal distribution of Staphylococcus aureus along a tropical Hawaiian watershed.

Staphylococcus aureus is a leading cause of community-acquired skin and soft-tissue infections worldwide. One major route of exposure is recreating in marine waters, but knowledge is limited regarding the drivers of S. aureus in surface waters that discharge into marine environments. This study explores spatial and temporal distributions of S. aureus, including antimicrobial-resistant and virulence genes, using both culture-dependent and molecular techniques across a tropical Hawaiian watershed with a gradient of human influence. Negative binomial generalized linear mixed models revealed that the interaction between spatial and temporal factors was the strongest predictor of S. aureus and associated genes. Cultured S. aureus was highest at mid-watershed sites in summer, which included a popular swimming hole, suggesting human shedding as a significant source. Molecular detection of S. aureus (femA gene) yielded concentrations two orders of magnitude higher than cultured concentrations and peaked at estuarine sites with the greatest nutrients and water residence times. In the winter at upstream sites with no public access, staphylococci antibiotic-resistant (mecA) and S. aureus virulence gene (etb) were elevated, indicating highly pathogenic S. aureus strains in surface waters may originate from zoonotic sources. Our findings indicate that human and zoonotic sources contribute antibiotic-resistant and virulent S. aureus to watersheds, with streams facilitating environmental transmission to marine waters. This watershed-scale assessment enables the prediction of spatial and temporal conditions associated with elevated S. aureus concentrations, thereby reducing exposure and infections.

Staphylococcus aureus

Mendelian randomisation for rheumatology: beyond hype-what it's good for, what it can't do, and how to read it critically.

Mendelian randomisation (MR) has become abundant in the literature, with variation in quality and frequent overinterpretation of causality. This creates a problem for clinical readers, reviewers, and editors: some MR studies can sharpen causal thinking, prioritise drug targets, and challenge misleading observational claims, whereas others are little more than automated exposure-outcome scans with causal claims disproportionate to the evidence. MR can strengthen causal inference when randomised trials are impractical and conventional observational studies are vulnerable to confounding, reverse causation, or selection bias. In rheumatology, credible MR can contribute to questions about disease aetiology, modifiable risk factors, therapeutic target validation, adverse-effect anticipation, and phenotype validation. However, its interpretation depends on whether the exposure is plausibly instrumentable, whether the genetic instruments are biologically defensible, whether assumptions are interrogated in ways appropriate to the design, and whether findings are triangulated with clinical, observational, experimental, and mechanistic evidence. Instead of recapitulating all methodological issues of MR, this review aims to help rheumatologists distinguish robust MR from weak or overinterpreted analyses quickly. We provide an accessible framework for reading and triaging MR studies in rheumatology. Papers that use poorly justified instruments, treat medication use as drug-target evidence, interpret genetic liability as diagnosis, rely on mechanical sensitivity analyses, ignore prior evidence or ask no clinically meaningful question can often be passed over by readers. The goal is not to discourage MR in rheumatology, but to raise the standard; useful MR should clarify causal reasoning rather than simply generate another statistically significant association.

Journal Article

ARR1 and ARR12 negatively regulate arsenic stress tolerance by controlling flavonoid metabolism in Arabidopsis.

ARR1/12-mediated cytokinin signaling negatively regulates the accumulation of glycosylated flavonoids, thereby increasing plant susceptibility to As(III) stress. Cytokinins negatively regulate arsenic stress tolerance in plants through cytokinin-signaling type-B Arabidopsis response regulators (B-ARRs), specifically ARR1 and ARR12. However, the mechanism by which cytokinin signaling regulates plant metabolite dynamics, particularly antioxidant flavonoids, in response to arsenic toxicity remains largely unknown. Here, we hypothesized that ARR1/12-mediated cytokinin signaling modulates flavonoid metabolism to regulate arsenite [As(III)] tolerance. By comparing the global metabolic changes in roots of the arr1 12 double mutant (rD) and wild-type (WT) plants, we found that As(III) stress globally reduced metabolite abundance in WT roots. Importantly, the rD mutant accumulated significantly more flavonoids, most in glycosylated forms, than WT under As(III) exposure, which was supported by the specific upregulation of UDP-glycosyltransferase genes involved in flavonoid glycosylation. Accordingly, exogenous application of the glycosylated quercitrin-enhanced As(III) tolerance in WT roots, strengthening that the increase of glycosylated flavonoids in rD roots was beneficial for plant survival under As(III) exposure. Our data collectively strongly support that the increased glycosylation of flavonoids in the rD mutant improves their antioxidant functionality, thereby enhancing the As(III) stress tolerance. This study provides a new insight into the negative role of cytokinin signaling in repressing glycosylated flavonoid accumulation, causing increased susceptibility of plants to As(III) stress. Manipulation of cytokinin signaling or flavonoid glycosylation is, therefore, a promising approach for heavy metal stress mitigation in crops.

Arabidopsis

Validated UPLC-MS/MS quantification and intracellular PK-PD Modeling of periplocin-related cardiac glycosides in H/R-injured H9c2 cells.

Reliable intracellular quantification is essential for characterizing the target-site disposition and exposure-response relationships of bioactive natural products. In this study, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of periplocin and four related cardiac glycoside metabolites in H9c2 cell lysates. Acceptable linearity, precision, recovery, and stability were achieved for intracellular quantification. Cells were treated with each compound at 50 μM, and intracellular concentrations and cell viability were monitored over 48 h. In hypoxia/reoxygenation (H/R) -injured cells, the time to maximum intracellular concentration was shortened for all five compounds, indicating altered cellular disposition under injury conditions. Cell viability was improved by all compounds during the observation period. Pharmacokinetic-pharmacodynamic (PK-PD) integration was performed using a sigmoid Emax model, and acceptable model fits were obtained, with Akaike information criterion (AIC) values ranging from 79.22 to 130.46. Low apparent EC50 values were estimated under this single-dose design, whereas the estimated Ke0 values suggested delayed equilibration with the effect compartment. These findings indicate that sustained cytoprotective responses can be produced by periplocin and related metabolic markers in injured cardiomyocytes. This intracellular bioanalytical strategy provides a quantitative approach for linking cellular exposure to pharmacodynamic response and may support further evaluation of periplocin-related cardiac glycosides.

Tandem Mass Spectrometry

Branded packaging raises likelihood of cigarette purchasing in an experimental retail setting by increasing craving.

INTRODUCTION: Exposure to branded cigarette packaging in retail settings has been shown to be associated with purchasing behavior, but the mechanisms underlying this effect are unclear. This study tested whether cigarette craving and perceived health harms mediate the effect of branded packaging on cigarette purchasing in a simulated retail environment. METHODS: Young adults aged 21-34 who currently smoke cigarettes (n = 290) completed an experimental shopping task in the RAND StoreLab, a life-sized replica of a convenience store. Participants were randomly assigned to one of two conditions: (1) branding present, in which branded cigarette packages were displayed; and (2) branding absent condition, in which branded elements were removed and packages were standardized in a brown-green color and uniform text. Cigarette purchases were recorded, and participants completed post-shopping measures of cigarette craving and perceived health harms. Causal effect decomposition analyses were used to assess whether these variables mediated the effect of study condition on the likelihood of purchasing cigarettes. RESULTS: Craving, but not perceived health harms, partially mediated the effect of branded packaging on cigarette purchasing. Exposure to branded packs increased the likelihood of purchasing by elevating craving (average mediated effect = 2.4%, 95% CI 0.2% - 5.0%, p = .03). CONCLUSIONS: Branded cigarette packaging appears to increase cigarette purchasing at least in part by increasing cigarette craving at point of sale. Interventions that address craving management in retail settings (e.g., just-in-time interventions, prn nicotine replacement therapy) may help mitigate the impact of branding on young adults' cigarette purchasing.

Humans

The effects of cold temperature on the development, microbiome, and transcriptome of the sea anemone Nematostella vectensis.

Thermal conditions impact essentially all aspects of the physiology for ectotherms. While the effects of high temperatures have been widely studied, cold temperature effects on aquatic invertebrates and their microbial communities have been poorly characterized. To determine the diverse effects of exposure to cold temperatures, we assessed acute and long-term impacts of ecologically relevant low temperatures on the development, microbiome, and gene expression of the sea anemone Nematostella vectensis. Two hours post fertilization, embryos were exposed to temperatures from 4°C to 35°C and development rate to the juvenile stage was quantified. We found temperature impacts the development rate of embryos, where lower temperatures extended development time and resulted in mortality below 10°C. For both microbiome and host transcriptomic responses, anemones were held at 20°C, 10°C, and 0°C and compared at 24 hours and 7 days. Extended exposures to colder temperatures caused restructuring of the host-associated microbiome, with the loss of common taxonomic groups from the class Bacteroidia and Bacilli. Lastly, cold stress induced significant changes in gene expression, which were more pronounced at the 10°C than 0°C but showed little change over time in each temperature. Interestingly, expression of genes associated with innate immunity were among the most differentially expressed genes including heat shock proteins and innate immune genes providing a potential host-imposed mechanism to explain the shift in the microbiome. Overall, cold temperatures have broad effects on many facets of this sea anemone and its microbial community and indicate the importance of cold temperature events when characterizing how ectotherms acclimate to thermal variation.

Animals

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 μg/L) of tebuconazole, either by itself or alongside the neonicotinoid thiacloprid (100 μg/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

Joint association of sedentary behaviour and physical activity with cardiovascular disease: a systematic review and meta-analysis.

This systematic review and meta-analysis of cohort studies aimed to synthesize existing evidence on the joint association of physical activity (PA) and sedentary behaviour (SB) with cardiovascular disease (CVD) risk among adults. We searched PubMed, EMBASE, and Cochrane for English studies published between January 2010 and February 2025 that examined the joint association of PA and SB (fatal and non-fatal) CVD among adults and pooled their results through meta-analyses using study-level data. Using findings from 17 studies, the pooled effect size for the lowest PA + highest SB group was 1.78 (95% CI: 1.59-2.00), suggesting increased risk for CVD compared with the reference group (i.e. highest PA + lowest SB). Compared with the same reference group, we found an increased risk for CVD in the lowest PA + lowest SB (HR = 1.25, 95% CI: 1.12-1.40) and the highest PA + highest SB (HR = 1.16, 95% CI: 1.06-1.27) groups. Subgroup analyses according to domains or types of PA and SB exposure, outcome measures, and exposure measurement method revealed a similar pattern. In conclusion, individuals with the lowest PA combined with the highest SB may experience an increased risk for CVD events compared with those with the highest PA and lowest SB. There was also an increased risk for individuals with a combination of either low PA + low SB and high PA + high SB, albeit to a lesser extent. Although substantial study-level heterogeneity exists, the results highlight the potential value of considering both behaviours jointly in relation to CVD risk.

Humans

Shielding performance and clinical applicability of lead-free materials in computed tomography.

Owing to the high radiation exposure associated with computed tomography (CT) examinations and the image quality degradation caused by conventional radiation shielding materials, this study evaluated the dose reduction performance and image quality maintenance potential of a newly developed lead-free composite shielding material. This material was composed of bismuth, tungsten, tungsten carbide, aluminium, and polyurethane. Phantom-based dose measurements demonstrated that the shielding material achieved dose reduction rates ranging from 17.6% to 37.6%, depending on tube voltage. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and changes in tube current-time product (mAs) under a scout-based automatic exposure control (AEC) protocol were analysed according to the presence or absence of the shielding material across regions. For the clinical evaluation, CT scans were performed on four patients. Furthermore, the images were reviewed to evaluate whether this material affected image quality. The shielding material exhibited radiation reduction levels comparable to those reported in previous studies. SNR and CNR analyses showed minor statistical variations in certain regions; however, most differences were not statistically significant, and even significant differences remained within a range that did not compromise diagnostic image quality. Under the scout-based AEC protocol, the use of the shielding material resulted in less than 1% variation in mAs values. No visually perceptible artefacts or clinically significant image quality degradation were observed. The proposed composite shielding material demonstrated the potential to mitigate some limitations of conventional shielding materials and showed preliminary clinical feasibility as an adjunctive strategy for radiation dose reduction in CT examinations.

Radiation Protection

Non-smoked cannabis consumption formats and Cannabis Use Disorder severity in an illicit setting: Evidence from Chile, 2020-2024.

BACKGROUND: Cannabis Use Disorder (CUD) has become an increasing public health burden, particularly in Chile. Non-smoked cannabis formats and products have been independently associated with CUD but remain understudied in the region. This study compares CUD severity among individuals aged 12 to 65 in Chile who consume cannabis via edibles, vaporization or both versus those who exclusively smoke it. METHODS: We obtained secondary data from three waves of the Chilean National Survey on Drugs in the General Population (ENPG), a three-stage stratified probabilistic sampling design study conducted in 2020, 2022, and 2024. Our pooled cross-sectional sample included individuals (n = 3543) who reported cannabis use in vaped, edible, both vaped and edible or exclusively smoked format in the past 12 months. We used a partial proportional odds model to estimate the association between CUD severity and consumption formats. RESULTS: Cannabis vaping group showed higher odds of presenting at least mild CUD (OR = 6.21 [95% CI: 3.75-10.3]), as did the edible group (OR = 1.73 [95% CI: 1.08-2.78]) and both group (OR = 5.92 [95% CI: 2.72-12.87]), compared to exclusive smokers. However, only the vaped group demonstrated higher odds for all severity levels. CONCLUSION: Compared with exclusive smokers, users of vaporizers and/or edibles showed a stronger association with CUD. This association may be explained by consumption patterns and total THC exposure. Further research is needed to characterize the average THC exposure by consumption format, acknowledging contextual confounders such as the legal framework.

Humans

Meta-analysis of growth and inactivation kinetics of Legionella.

Quantitative risk assessments intended to inform evidence-based water management plans and public health targets for Legionella in engineered water systems are constrained by fragmented and heterogeneous growth and inactivation kinetics. We conducted a meta-analysis of 25 growth and 39 thermal- and chemical-inactivation studies, fitting microbial persistence models to harmonize parameters. Nonlinear models outperformed first-order formulations, indicating that lag phases and resistant or protected subpopulations are central to Legionella persistence. Random forest analysis identified environmental and methodological drivers of variability based on 226 growth rates and reduction times for thermal (209) and chemical (135) inactivation. Growth was primarily governed by temperature, nutrient availability, and compatible Legionella-host pairings; thermal inactivation by quantification method, temperature, and turbidity; and chemical inactivation by inoculum size, disinfectant type, concentration, and host-associations. Accordingly, temperature-dependent growth parameters and exposure metrics for heat, free-chlorine, and monochloramine, expressed as TT (Temperature×time) and CT (Concentration×time), were derived as condition-specific inputs for predictive models. Growth optima around 37-40 °C, together with lag-time estimates, indicate that hot-water temperature setbacks and energy-saving practices may favor Legionella proliferation under repeated or prolonged lukewarm exposure. Culture- and viability-based TT differences highlight the need to consider viable‑but-non-culturable persistence in monitoring programs. CT comparisons suggest monochloramine may be advantageous because of its lower apparent sensitivity to host-associated protection. Although limited by restricted experimental conditions, the findings show that predictive models should account for microbial ecology, water matrix effects, and quantification endpoints. Future kinetic studies should prioritize realistic multi-host systems, strain pre-adaptation, complementary viability measurements, and standardized protocols and reporting to ensure reproducibility and enable robust system-level predictive modeling.

Legionella

Simultaneously PYCR-1 and ALH-6 inhibition exacerbates 6-PPD quinone toxicity via disrupting proline and glutamate metabolisms and activating insulin signals in Caenorhabditis elegans.

Glutamate synthesized from the proline can serve as a precursor for key intermediate metabolites of citric acid cycle. Recently, we observed reduced glutamate content and expression of alh-6 controlling glutamate synthesis by 6-PPD quinone (6-PPDQ) in Caenorhabditis elegans. However, possible effect of 6-PPDQ on proline synthesis and the association with 6-PPDQ toxicity induction remain unclear. After 0.1-10 μg/L 6-PPDQ exposure, proline content was further reduced, and expression of pycr-1 governing proline biosynthesis was decreased. In 6-PPDQ exposed nematodes, RNA interference (RNAi) of pycr-1 decreased α-ketoglutarate content, enhanced mitochondrial dysfunction, reduced nicotinamide adenine dinucleotide (NADH) and reduced flavine adenine dinucleotide (FADH₂) contents, inhibited mitochondrial complex I/II activities, and decreased expressions of gas-1 and mev-1. Moreover, compared to single RNAi, double RNAi of pycr-1 and alh-6 exacerbated the 6-PPDQ toxicity in reducing α-ketoglutarate, NADH, and FADH₂ contents, and suppressing mitochondrial complex I/II activities and gas-1 and mev-1 expressions. Additionally, double RNAi of pycr-1 and alh-6 intensified toxicity of 6-PPDQ on longevity and caused upregulation of insulin ligand and receptor genes and downregulation of daf-16 and its targeted genes in 6-PPDQ exposed nematodes. Furthermore, after 6-PPDQ exposure, daf-16 RNAi suppressed pycr-1 and alh-6 expressions, suggesting formation of a regulatory feedback loop between pycr-1/alh-6 and daf-16. Our findings highlight involvement of disrupted proline and glutamate metabolisms in 6-PPDQ-induced mitochondrial dysfunction and reduced longevity.

Animals