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Aflatoxins and their biosynthetic precursors in lotus seeds: simultaneous UPLC-MS/MS determination, contamination profiling, and matrix-specific accumulation during Aspergillus flavus infection.

Aflatoxin (AF) contamination poses a severe global threat to food and medicinal material safety, yet existing research focuses on terminal AF metabolites while neglecting residual biosynthetic precursors, leading to potential underestimation of contamination risks. In this study, a UPLC-MS/MS method was established for the simultaneous quantification of six AFs and their five precursors in lotus seeds, with optimization of mass spectrum parameters, chromatographic separation conditions, and sample pretreatment. Method validation confirmed linearity (R2&#xa0;>&#xa0;0.99), LODs (0.03-0.36&#xa0;&#x3bc;g/kg), and recoveries (76.53%-120.0%, RSD&#xa0;<&#xa0;15%). Analysis of 41 natural lotus seed samples revealed a 63.4% AF contamination rate, dominated by B-group AFs, while O-methylsterigmatocystin (OMST) and versicolorin hemiacetal (VOH) were identified as the primary co-residual precursors with co-occurrence rates &#x2265; 50%. Notably, AFM1 was predominantly detected in natural samples with AFB1 concentrations exceeding 100&#xa0;&#x3bc;g/kg. Artificial inoculation experiments further demonstrated that sterilization and sealing conditions modulated AF biosynthesis in lotus seeds, with non-sterilized and non-sealed groups showing delayed fungal metabolism and lower toxin accumulation. A significant linear correlation was observed between AFM1 and AFB1 levels (r&#xa0;=&#xa0;0.94) in infected samples, demonstrating their accumulation levels are coupled with fungal overall metabolic flux. Given the high co-occurrence rate of OMST/VOH with AFB1 in natural samples, their individual and combined toxicities require in-depth investigation. This work deciphers matrix-specific AF dynamics in lotus seeds, supporting regulatory standard refinement (e.g., precursor inclusion) and targeted control (e.g., time-sensitive drying after harvest). Further studies will focus on exploring the molecular mechanisms of substrate-dependent AF synthesis.

Aflatoxins

The effects of nitrate and nitrite supplementation on mitochondrial respiration in permeabilized muscle fibres in young healthy adults.

Nitric oxide (NO) is a direct regulator of mitochondrial respiration. Nitrate (NO3-) and nitrite (NO2-) are good sources of NO, but whether their effects on mitochondrial respiration differ between in vivo and in vitro administration remains unclear. In Study 1, 8 participants consumed NO3- -rich beetroot juice (BR) (&#x223c;12.8&#x202f;mmol NO3-) and NO3- -depleted placebo beetroot juice (PL) (&#x223c;0.08&#x202f;mmol NO3-) acutely and chronically for 2 weeks in a randomised, double-blind, crossover design. A substrate-uncoupler-inhibitor titration (SUIT) protocol was used to assess mitochondrial respiration using high-resolution respirometry (oxygen tension: &#x223c;200-450&#x202f;&#x3bc;M) in permeabilized muscle fibres. In Study 2, skeletal muscle samples were collected from 11 participants. In a randomised, crossover design, different doses (0, 1.5, and 3.0&#x202f;&#x3bc;M) of sodium nitrite (NaNO2) were administered to permeabilized muscle fibres. Mitochondrial respiration was measured using the same SUIT protocol under lower oxygen tension (&#x223c;50-200&#x202f;&#x3bc;M). Although muscle NO3- concentration significantly increased after both acute and chronic BR supplementation, mitochondrial respiration and exercise performance did not differ between PL and BR in either condition. Similarly, absolute oxygen flux across different respiratory states were not different between different doses of NaNO2. However, the leak control ratio, reflecting the degree of uncoupling of mitochondrial respiration, was significantly higher with 3.0&#x202f;&#x3bc;M NaNO2 administration (0.12&#x202f;&#xb1;&#x202f;0.05) compared to 0&#x202f;&#x3bc;M NaNO2 administration (0.09&#x202f;&#xb1;&#x202f;0.04, P&#x202f;=&#x202f;0.03). These findings, involving both in vivo and in vitro administration approaches, albeit in the presence of relatively high oxygen concentrations, suggest that neither NO3- nor NO2- improves mitochondrial respiration, at least in young healthy adults.

Humans

Integrative quantum and systems biology of cancer: From molecular fluctuations to ecological outcomes.

This review treats cancer as a multiscale adaptive system, asks what the framework must predict to be worth adopting, and separates at each scale what the evidence establishes from what is proposed. It is an expert narrative synthesis, not a systematic review, and states the limits of that design. Proton transfer and tautomeric shifts contribute to spontaneous mispairing but do not license claims of directed or non-random mutation: replication timing, three-dimensional chromatin organization, sequence context and known mutagenic processes explain most mutational heterogeneity, leaving any quantum contribution as a residual against that baseline. The Waddington quasi-potential is bounded: outside detailed balance the dynamics are not gradient-derivable and require a probability-flux term. Hysteresis, rate-limited bimodality and return to state after perturbation distinguish an attractor from a transcriptomic cluster. Single-cell karyotype and live-imaging evidence supports whole-genome doubling as an unstable intermediate of heterogeneous origin and context-dependent consequence, not a uniform adaptive strategy. Systems and synthetic biology, virtual cells and digital twins are assessed against benchmarks, not promise. Tissue-scale ecology is reported with the spatial measurements now quantifying it, including evidence that stromal niche construction is not uniformly tumor-supporting. RNA modification is a layer in its own right, showing that the interpretation of a regulatory signal, not its magnitude, is biologically decisive. A dedicated section states the framework's commitments, the observable and evidence at each scale, and what would falsify them, asking what this adds to somatic mutation theory with clonal evolution and plasticity.

Neoplasms

Impacts of climate-driven yield changes on the affordability of healthy diets: a modelling study.

BACKGROUND: Food security is central to global nutrition improvement and public health goals, and healthy diets represent a higher-level aspiration beyond merely avoiding hunger. Climate change poses an increasing threat to food systems by affecting crop yields and food prices. Although climate change-driven risks to hunger have been widely studied, the extent to which climate change undermines the affordability of healthy diets while accounting for socioeconomic responses and regional inequalities remains insufficiently understood. This study aimed to quantify the effects of climate change on the future affordability of healthy diets under alternative socioeconomic and climate scenarios. METHODS: We developed an integrated modelling framework that explicitly couples multimodel crop-yield projections with an integrated assessment model (Global Change Analysis Model [GCAM]). Yield responses from six global gridded crop models driven by four climate models were integrated into GCAM, allowing endogenous socioeconomic adjustments such as land-use shifts, production reallocation, and price responses to emerge under shared socioeconomic pathways (SSPs). Diet affordability was then assessed using the Food and Agriculture Organization of the UN's Cost and Affordability of a Healthy Diet framework across three socioeconomic-climate scenarios (SSP1-2.6, SSP2-4.5, and SSP3-6.0). FINDINGS: Under a high-emissions pathway (ie, SSP3-6.0), climate change was projected to render healthy diets unaffordable for a model-mean of 119 million people globally by 2100, even when CO2 fertilisation effects are included, with the upper end of the model ensemble reaching about 1&#xb7;6 billion people. In contrast, climate-induced affordability losses were found to be negligible under both a low-emissions pathway (ie, SSP1-2.6; -0&#xb7;3 million) and a medium-emission pathway (SSP2-4.5; +0&#xb7;2 million). Under a high-emission pathway, model-mean projections indicated that diet costs could increase by up to 12% in the most affected regions by the end of the century. Under medium emissions, cost increases were projected to remain below 4%, whereas under low emissions, affordability changes were projected to be minimum across regions (within approximately 0&#xb7;5%). Substantial regional disparities emerged, with the largest and most consistent affordability losses concentrated in low-income regions that contributed least to historical greenhouse gas emissions. Under SSP3-6.0, these disparities persisted particularly in regions of Africa and Asia despite projected three-to-five-fold increases in income over the century, with climate-induced disruptions to food systems increasing the number of people unable to afford a healthy diet through mid-century. INTERPRETATION: Climate change is likely to exacerbate global nutritional inequalities by disproportionately increasing the affordability risks of healthy diets in regions that have contributed least to historical greenhouse gas emissions. Under high-warming scenarios, socioeconomic development alone is insufficient to fully offset these risks, highlighting the structural vulnerability of low-income food systems to climate-driven price shocks. These findings suggest that in the absence of targeted interventions, climate change could continue to undermine progress towards equitable and health-oriented nutrition outcomes. FUNDING: Ministry of Science and Technology of the People's Republic of China; National Natural Science Foundation of China; National Aeronautics and Space Administration Goddard Institute for Space Studies Climate Impacts Group; Future of Life Institute; and Global Alliance for Improved Nutrition.

Journal Article

Impact of a thermal care bundle on peri-operative hypothermia, surgical site infection, and readmissions in osteosynthesis patients: A randomised controlled trial.

BACKGROUND: Maintaining normothermia throughout the peri-operative period prevents the occurrence of complications related to hypothermia. OBJECTIVE: To determine the effect of a thermal care bundle with a short prewarming period on inadvertent peri-operative hypothermia (IPH), surgical site infection (SSI), and unplanned readmission among osteosynthesis patients, and to identify associated variables. DESIGN: Open-label, randomised controlled trial. SETTING: University hospital. PATIENTS: One hundred and forty-eight patients who underwent osteosynthesis surgery. INTERVENTION: The intervention group received the thermal care bundle, which consisted in prewarming patients 10&#x200a;min before anaesthesia delivery and maintaining body temperature with a forced air device during surgery and the immediate postoperative period; in addition, the operating room environmental temperature was kept at 21&#x200a;&#xb0;C, and fluids were warmed to 38&#x200a;&#xb0;C. MAIN OUTCOME MEASURES: For the primary objective, hypothermia was defined as core body temperature below 36&#x200a;&#xb0;C and measured using the 3M Spot On zero heat flux sensor. Core temperature was recorded upon admission to the pre-operative holding area and subsequently every 30&#x200a;min until postanaesthesia care unit (PACU) discharge. Secondary objectives were SSI and readmissions: a follow-up at 30 to 60 and 90&#x200a;days was performed by the principal investigator. RESULTS: All 148 patients completed the study, and there were no significant differences between the groups at baseline. At the start of surgery, the incidence of hypothermia was significantly lower in the bundle group (1.3 vs. 9.9% among controls; odds ratio&#x200a;=&#x200a;7.59, P &#x200a;=&#x200a;0.021). A significantly lower incidence of hypothermia was also observed at admission to the PACU (14.3% in the bundle group vs. 29.6% among controls; odds ratio&#x200a;=&#x200a;2.07; P &#x200a;=&#x200a;0.024). Application of the bundle increased patients' core body temperature by 0.13&#x200a;&#xb0;C (95% confidence interval (CI), 0.003 to 0.254; P &#x200a;=&#x200a;0.045). Patients in the bundle group had a slightly lower observed incidence of wound infections requiring readmission (odds ratio&#x200a;=&#x200a;0.35; 95% CI, 0.04 to 2.92), although this difference was not statistically significant ( P &#x200a;=&#x200a;0.332). CONCLUSIONS: The bundle reduces peri-operative hypothermia by up to 59%, but does not affect on SSI; factors like presurgery hospital stay, operating room and PACU occupancy were identified as risk factors for SSI. REGISTRATION: 21 July 2022: NCT05469958 (Clinical Trials.gov), first recruitment 15 August 2022.

Adult